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1.
CJC Open ; 6(5): 728-734, 2024 May.
Article in English | MEDLINE | ID: mdl-38846443

ABSTRACT

Background: High blood pressure (BP) is a leading cause of cardiovascular and stroke-related events. Office-based BP measurement has declined in recent years due to the COVID-19 pandemic, which may have resulted in higher rates of undetected and uncontrolled hypertension. To gain a better idea of adult BP levels in Newfoundland and Labrador, we engaged community pharmacists in BP screening on World Hypertension Day. Methods: Data collection and BP screening occurred on May 17, 2022. Pharmacists and pharmacy students collected 3 seated BP readings from participants, using an automated device. The average of readings 2 and 3 was used to estimate BP, with elevated BP defined as ≥ 140/90 mm Hg, or ≥ 130/80 mm Hg for individuals with diabetes. Data on participant demographics, access to primary care, medical history, and antihypertensive use were also collected. Data analysis included descriptive statistics and logistic regression techniques. Results: A total of 460 participants were included in the analysis. The mean age was 56.3 years (standard deviation: 16.95); 63.3% (n = 291) were female; and 43.7% (n = 201) reported having hypertension. Elevated BP was identified in 27% (n = 123). Of those with elevated BP, 41.5% (n = 51) had no history of diagnosed hypertension. Age, sex, and diabetes were statistically significant predictors of elevated BP in the multivariable model. Conclusions: A large proportion of participants in our study had elevated BP. Targeted measures are needed to improve the detection, treatment, and control of high BP in Newfoundland and Labrador. Community pharmacists can support BP care.


Contexte: L'hypertension artérielle est une cause majeure d'événements cardiovasculaires et d'AVC. Or, la mesure de la pression artérielle (PA) en clinique a connu un déclin ces dernières années en raison de la pandémie de COVID-19, de sorte que les taux d'hypertension artérielle non détectée et non maîtrisée pourraient avoir augmenté. Afin de nous faire une idée plus précise de l'état de la PA des adultes de Terre-Neuve-et-Labrador, nous avons organisé une campagne de mesure de la PA dans les pharmacies de détail à l'occasion de la Journée mondiale de l'hypertension artérielle. Méthodologie: La collecte des données et les mesures ont eu lieu le 17 mai 2022. Les pharmaciens aidés par des étudiants en pharmacie ont pris 3 relevés en position assise par participant à l'aide d'un dispositif de mesure automatisé. La moyenne des 2 derniers relevés a été utilisée pour obtenir la PA estimative. La PA était considérée comme élevée si les valeurs étaient égales ou supérieures à 140/90 mmHg, ou à 130/80 mmHg chez les personnes diabétiques. D'autres renseignements ont été recueillis, notamment les caractéristiques démographiques des participants, leur accès aux soins primaires, leurs antécédents médicaux et leur prise d'antihypertenseurs. Les données ont ensuite été analysées à l'aide de statistiques descriptives et de techniques de régression logistique. Résultats: Au total, 460 participants ont été inclus dans l'analyse. L'âge moyen était de 56,3 ans (écart-type : 16,95); 63,3 % (n = 291) étaient de sexe féminin et 43,7 % (n = 201) ont indiqué être atteints d'hypertension. Une PA élevée a été observée chez 27 % des participants (n = 123), dont 41,5 % (n = 51) qui n'avaient jamais reçu un diagnostic d'hypertension artérielle. L'âge, le sexe et le diabète se sont avérés des facteurs de prédiction de PA élevée statistiquement significatifs dans un modèle multivarié. Conclusions: Un pourcentage important des participants à notre étude présentait une PA élevée. Des mesures ciblées s'imposent pour mieux dépister, traiter et maîtriser l'hypertension artérielle à Terre-Neuve-et-Labrador. Les pharmaciens de proximité pourraient également jouer un rôle dans la surveillance de la PA.

2.
Eur Heart J Cardiovasc Imaging ; 25(6): 804-813, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38236156

ABSTRACT

AIMS: We sought to characterize sex-related differences in cardiovascular magnetic resonance-based cardiovascular phenotypes and prognosis in patients with idiopathic non-ischaemic cardiomyopathy (NICM). METHODS AND RESULTS: Patients with NICM enrolled in the Cardiovascular Imaging Registry of Calgary (CIROC) between 2015 and 2021 were identified. Z-score values for chamber volumes and function were calculated as standard deviation from mean values of 157 sex-matched healthy volunteers, ensuring reported differences were independent of known sex-dependencies. Patients were followed for the composite outcome of all-cause mortality, heart failure admission, or ventricular arrhythmia. A total of 747 patients were studied, 531 (71%) males. By Z-score values, females showed significantly higher left ventricular (LV) ejection fraction (EF; median difference 1 SD) and right ventricular (RV) EF (difference 0.6 SD) with greater LV mass (difference 2.1 SD; P < 0.01 for all) vs. males despite similar chamber volumes. Females had a significantly lower prevalence of mid-wall striae (MWS) fibrosis (22% vs. 34%; P < 0.001). Over a median follow-up of 4.7 years, 173 patients (23%) developed the composite outcome, with equal distribution in males and females. LV EF and MWS were significant independent predictors of the outcome (respective HR [95% CI] 0.97 [0.95-0.99] and 1.6 [1.2-2.3]; P = 0.003 and 0.005). There was no association of sex with the outcome. CONCLUSION: In a large contemporary cohort, NICM was uniquely expressed in females vs. males. Despite similar chamber dilation, females demonstrated greater concentric remodelling, lower reductions in bi-ventricular function, and a lower burden of replacement fibrosis. Overall, their prognosis remained similar to male patients with NICM.


Subject(s)
Cardiomyopathies , Magnetic Resonance Imaging, Cine , Phenotype , Humans , Male , Female , Middle Aged , Cardiomyopathies/diagnostic imaging , Cardiomyopathies/physiopathology , Prognosis , Magnetic Resonance Imaging, Cine/methods , Sex Factors , Aged , Stroke Volume/physiology , Registries , Retrospective Studies
3.
Opt Lett ; 48(17): 4424-4427, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37656519

ABSTRACT

We demonstrate numerical refocusing in coherent confocal laser scanning microscopy based on synthetic optical holography. In this physics-based approach, computational propagation is implemented on the complex signal recovered in synthetic holography, consistent with wave physics and the parameters of the microscope. An experimental demonstration is shown to restore an in-focus image of a test object from data acquired at several focal plane off-sets. Numerical refocusing can provide focused views on samples with large height variation, with a potential application in confocal optical surface profiling.

4.
Pediatr Res ; 94(5): 1744-1753, 2023 11.
Article in English | MEDLINE | ID: mdl-37277605

ABSTRACT

BACKGROUND: Paediatric inflammatory multisystem syndrome (PIMS) is a rare condition temporally associated with SARS-CoV-2 infection. Using national surveillance data, we compare presenting features and outcomes among children hospitalized with PIMS by SARS-CoV-2 linkage, and identify risk factors for intensive care (ICU). METHODS: Cases were reported to the Canadian Paediatric Surveillance Program by a network of >2800 pediatricians between March 2020 and May 2021. Patients with positive versus negative SARS-CoV-2 linkages were compared, with positive linkage defined as any positive molecular or serologic test or close contact with confirmed COVID-19. ICU risk factors were identified with multivariable modified Poisson regression. RESULTS: We identified 406 children hospitalized with PIMS, including 49.8% with positive SARS-CoV-2 linkages, 26.1% with negative linkages, and 24.1% with unknown linkages. The median age was 5.4 years (IQR 2.5-9.8), 60% were male, and 83% had no comorbidities. Compared to cases with negative linkages, children with positive linkages experienced more cardiac involvement (58.8% vs. 37.4%; p < 0.001), gastrointestinal symptoms (88.6% vs. 63.2%; p < 0.001), and shock (60.9% vs. 16.0%; p < 0.001). Children aged ≥6 years and those with positive linkages were more likely to require ICU. CONCLUSIONS: Although rare, 30% of PIMS hospitalizations required ICU or respiratory/hemodynamic support, particularly those with positive SARS-CoV-2 linkages. IMPACT: We describe 406 children hospitalized with paediatric inflammatory multisystem syndrome (PIMS) using nationwide surveillance data, the largest study of PIMS in Canada to date. Our surveillance case definition of PIMS did not require a history of SARS-CoV-2 exposure, and we therefore describe associations of SARS-CoV-2 linkages on clinical features and outcomes of children with PIMS. Children with positive SARS-CoV-2 linkages were older, had more gastrointestinal and cardiac involvement, and hyperinflammatory laboratory picture. Although PIMS is rare, one-third required admission to intensive care, with the greatest risk amongst those aged ≥6 years and those with a SARS-CoV-2 linkage.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Male , Child , Child, Preschool , Female , COVID-19/epidemiology , COVID-19/therapy , Canada/epidemiology , Systemic Inflammatory Response Syndrome/diagnosis , Systemic Inflammatory Response Syndrome/epidemiology
5.
Can Commun Dis Rep ; 49(4): 103-112, 2023 Apr 01.
Article in English | MEDLINE | ID: mdl-38356877

ABSTRACT

Background: Direct comparisons of paediatric hospitalizations for acute coronavirus disease 2019 (COVID-19) and multisystem inflammatory syndrome in children (MIS-C) can inform health system planning. We describe the absolute and relative hospital burden of acute paediatric COVID-19 and MIS-C in Canada. Methods: This national prospective study was conducted via the Canadian Paediatric Surveillance Program from March 2020-May 2021. Children younger than 18 years old and hospitalized for acute COVID-19 or MIS-C were included in the analysis. Outcomes included supplemental oxygen (low-flow oxygen or high-flow nasal cannula), ventilation (non-invasive or conventional mechanical), vasopressors, paediatric intensive care unit (PICU) admission, or death. Adjusted risk differences (aRD) and 95% confidence intervals (CI) were calculated to identify factors associated with each diagnosis. Results: Overall, we identified 330 children hospitalized for acute COVID-19 (including five deaths) and 208 hospitalized for MIS-C (including zero deaths); PICU admission was required for 49.5% of MIS-C hospitalizations versus 18.2% of acute COVID-19 hospitalizations (aRD 20.3; 95% CI, 9.9-30.8). Resource use differed by age, with children younger than one year hospitalized more often for acute COVID-19 (aRD 43.4% versus MIS-C; 95% CI, 37.7-49.1) and more children 5-11 years hospitalized for MIS-C (aRD 38.9% vs. acute COVID-19; 95% CI, 31.0-46.9). Conclusion: While there were more hospitalizations and deaths from acute paediatric COVID-19, MIS-C cases were more severe, requiring more intensive care and vasopressor support. Our findings suggest that both acute COVID-19 and MIS-C should be considered when assessing the overall burden of severe acute respiratory syndrome coronavirus 2 in hospitalized children.

6.
Lancet Reg Health Am ; 15: 100337, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35936225

ABSTRACT

Background: Children living with chronic comorbid conditions are at increased risk for severe COVID-19, though there is limited evidence regarding the risks associated with specific conditions and which children may benefit from targeted COVID-19 therapies. The objective of this study was to identify factors associated with severe disease among hospitalized children with COVID-19 in Canada. Methods: We conducted a national prospective study on hospitalized children with microbiologically confirmed SARS-CoV-2 infection via the Canadian Paediatric Surveillance Program (CPSP) from April 2020-May 2021. Cases were reported voluntarily by a network of >2800 paediatricians. Hospitalizations were classified as COVID-19-related, incidental infection, or infection control/social admissions. Severe disease (among COVID-19-related hospitalizations only) was defined as disease requiring intensive care, ventilatory or hemodynamic support, select organ system complications, or death. Risk factors for severe disease were identified using multivariable Poisson regression, adjusting for age, sex, concomitant infections, and timing of hospitalization. Findings: We identified 544 children hospitalized with SARS-CoV-2 infection, including 60·7% with COVID-19-related disease and 39·3% with incidental infection or infection control/social admissions. Among COVID-19-related hospitalizations (n=330), the median age was 1·9 years (IQR 0·1-13·3) and 43·0% had chronic comorbid conditions. Severe disease occurred in 29·7% of COVID-19-related hospitalizations (n=98/330 including 60 admitted to intensive care), most frequently among children aged 2-4 years (48·7%) and 12-17 years (41·3%). Comorbid conditions associated with severe disease included pre-existing technology dependence requirements (adjusted risk ratio [aRR] 2·01, 95% confidence interval [CI] 1·37-2·95), body mass index Z-scores ≥3 (aRR 1·90, 95% CI 1·10-3·28), neurologic conditions (e.g. epilepsy and select chromosomal/genetic conditions) (aRR 1·84, 95% CI 1·32-2·57), and pulmonary conditions (e.g. bronchopulmonary dysplasia and uncontrolled asthma) (aRR 1·63, 95% CI 1·12-2·39). Interpretation: While severe outcomes were detected at all ages and among patients with and without comorbidities, neurologic and pulmonary conditions as well as technology dependence were associated with increased risk of severe COVID-19. These findings may help guide vaccination programs and prioritize targeted COVID-19 therapies for children. Funding: Financial support for the CPSP was received from the Public Health Agency of Canada.

7.
CMAJ ; 193(46): E1774-E1785, 2021 11 22.
Article in French | MEDLINE | ID: mdl-34810167

ABSTRACT

CONTEXTE: Les facteurs de risque de complications graves de l'infection par le SRAS-CoV-2 n'ont pas été bien établis chez les enfants. Nous avons voulu décrire les hospitalisations pédiatriques associées au SRAS-CoV-2 au Canada et identifier les facteurs de risque de maladie grave. MÉTHODES: Nous avons procédé à une étude prospective nationale en utilisant l'infrastructure du Programme canadien de surveillance pédiatrique (PCSP). Les hospitalisations d'enfants ayant contracté une infection par le SRAS-CoV-2 confirmée en laboratoire de microbiologie ont été rapportées du 8 avril au 31 décembre 2020 au moyen de questionnaires hebdomadaires en ligne distribués au réseau du PCSP, qui compte plus de 2800 pédiatres. Nous avons catégorisé les hospitalisations comme suit : liées à la COVID-19, infections découvertes fortuitement, ou hospitalisations pour des raisons sociales ou de contrôle des infections, et dégagé les facteurs de risque associés à la gravité de la maladie chez les patients hospitalisés. RÉSULTATS: Sur les 264 hospitalisations d'enfants ayant contracté le SRAS-CoV-2 au cours de la période de l'étude de 9 mois, 150 (56,8 %) ont été associées à la COVID-19 et 100 (37,9 %) étaient des cas découverts fortuitement (admission pour d'autres raisons et découverte fortuite du SRAS-CoV-2 par dépistage positif). Les nourrissons (37,3 %) et les adolescents (29,6 %) représentaient la majorité des cas. Parmi les hospitalisations liées à la COVID-19, 52 patients (34,7 %) étaient atteints d'une forme grave de la maladie, dont 42 (28,0 % des cas liés à la COVID-19) ont eu besoin d'une forme d'assistance respiratoire ou hémodynamique, et 59 (39,3 %) présentaient au moins 1 comorbidité sous-jacente. Les enfants atteints d'obésité, de maladies neurologiques chroniques ou de maladies pulmonaires chroniques, à l'exclusion de l'asthme, étaient plus susceptibles de présenter une forme grave ou critique de la COVID-19. INTERPRÉTATION: Parmi les enfants hospitalisés au Canada chez lesquels on a diagnostiqué une infection par le SRAS-CoV-2 au début de la pandémie de COVID-19, la découverte fortuite du SRAS-CoV-2 a été fréquente. Chez les enfants hospitalisés pour une COVID-19 aiguë, l'obésité et les comorbidités neurologiques et respiratoires ont été associées à une gravité accrue.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Viral , Canada , Child , Hospitalization , Humans
8.
CMAJ ; 193(38): E1483-E1493, 2021 09 27.
Article in English | MEDLINE | ID: mdl-34580141

ABSTRACT

BACKGROUND: Risk factors for severe outcomes of SARS-CoV-2 infection are not well established in children. We sought to describe pediatric hospital admissions associated with SARS-CoV-2 infection in Canada and identify risk factors for more severe disease. METHODS: We conducted a national prospective study using the infrastructure of the Canadian Paediatric Surveillance Program (CPSP). Cases involving children who were admitted to hospital with microbiologically confirmed SARS-CoV-2 infection were reported from Apr. 8 to Dec. 31 2020, through weekly online questionnaires distributed to the CPSP network of more than 2800 pediatricians. We categorized hospital admissions as related to COVID-19, incidental, or for social or infection control reasons and determined risk factors for disease severity in hospital. RESULTS: Among 264 hospital admissions involving children with SARS-CoV-2 infection during the 9-month study period, 150 (56.8%) admissions were related to COVID-19 and 100 (37.9%) were incidental infections (admissions for other reasons and found to be positive for SARS-CoV-2 on screening). Infants (37.3%) and adolescents (29.6%) represented most cases. Among hospital admissions related to COVID-19, 52 (34.7%) had critical disease, 42 (28.0%) of whom required any form of respiratory or hemodynamic support, and 59 (39.3%) had at least 1 underlying comorbidity. Children with obesity, chronic neurologic conditions or chronic lung disease other than asthma were more likely to have severe or critical COVID-19. INTERPRETATION: Among children who were admitted to hospital with SARS-CoV-2 infection in Canada during the early COVID-19 pandemic period, incidental SARS-CoV-2 infection was common. In children admitted with acute COVID-19, obesity and neurologic and respiratory comorbidities were associated with more severe disease.


Subject(s)
COVID-19/epidemiology , Hospitalization , Severity of Illness Index , Acute Disease , Adolescent , COVID-19/diagnosis , COVID-19/etiology , COVID-19/therapy , COVID-19 Testing , Canada/epidemiology , Child , Child, Preschool , Comorbidity , Female , Humans , Incidental Findings , Infant , Infant, Newborn , Male , Prospective Studies , Public Health Surveillance , Risk Factors
9.
Emerg Infect Dis ; 23(13)2017 Dec.
Article in English | MEDLINE | ID: mdl-29155654

ABSTRACT

The 2014-2015 epidemic of Ebola virus disease in West Africa primarily affected Guinea, Liberia, and Sierra Leone. Several countries, including Mali, Nigeria, and Senegal, experienced Ebola importations. Realizing the importance of a trained field epidemiology workforce in neighboring countries to respond to Ebola importations, the Centers for Disease Control and Prevention Field Epidemiology Training Program unit implemented the Surveillance Training for Ebola Preparedness (STEP) initiative. STEP was a mentored, competency-based initiative to rapidly build up surveillance capacity along the borders of the at-risk neighboring countries Côte d'Ivoire, Mali, Senegal, and Guinea-Bissau. The target audience was district surveillance officers. STEP was delivered to 185 participants from 72 health units (districts or regions). Timeliness of reporting and the quality of surveillance analyses improved 3 months after training. STEP demonstrated that mentored, competency-based training, where learners attain competencies while delivering essential public health services, can be successfully implemented in an emergency response setting.

10.
AIDS ; 31(5): 635-641, 2017 03 13.
Article in English | MEDLINE | ID: mdl-28060008

ABSTRACT

OBJECTIVE: Heme oxygenase-1 (HO-1) is an inducible stress response protein with potent anti-inflammatory activity and recent data suggest a potentially beneficial role in HIV pathogenesis. We investigated the impact of HO-1 and a novel subset of HO-1-specific CD8 regulatory T cells on virus-specific T-cell immunity in HIV-1-infected individuals. METHODS: HO-1 protein levels were quantified in plasma from individuals at different stages of HIV-1 disease and longitudinally following primary HIV infection. HO-1-specific CD8 T cells were investigated by flow cytometry using human leukocyte antigen (HLA) class I pentamers. Flow-sorted HO-1-specific CD8 T cells were cultured and tested for suppressive activity on HIV-1-specific cytotoxic T-cell clones clones. HO-1 gene expression was determined in sorted peripheral blood mononuclear cell (PBMC) subsets from individuals with acute HIV-1 infection. RESULTS: HO-1 plasma levels were significantly increased in HIV-1 infection, with the highest levels in individuals with acute HIV-1 infection, and gradually declined over time. The frequency of CD8 T cells specific for HO-1 was elevated in study participants with primary HIV-1 infection and flow-sorted HO-1-specific CD8 T cells were capable of suppressing HIV-1-specific lysis of cytotoxic T-cell clones clones. HO-1 gene expression was upregulated in multiple immune cell subsets during acute HIV-1 infection and HO-1 overexpression modulated anti-HIV immunity in vitro. CONCLUSION: Our data suggest that HO-1 is induced during acute HIV-1 infection, likely mediating anti-inflammatory effects and driving expansion of HO-1-specific CD8 regulatory T cells capable of suppressing HIV-1-specific immune responses in vitro. The investigation of HO-1 and the novel CD8 regulatory cell type described here provide further insight into immune regulation in HIV-1 infection and may hold potential for future immunotherapeutic intervention.


Subject(s)
HIV Infections/immunology , HIV-1/immunology , Heme Oxygenase-1/blood , Plasma/enzymology , T-Lymphocytes, Regulatory/immunology , CD8-Positive T-Lymphocytes/immunology , Cells, Cultured , Flow Cytometry , HIV Infections/virology , Humans , Immunophenotyping , Longitudinal Studies
11.
Int J Cell Biol ; 2014: 495817, 2014.
Article in English | MEDLINE | ID: mdl-24729786

ABSTRACT

Intracerebral hemorrhage (ICH) is the most common form of hemorrhagic stroke, accounting for 15% of all strokes. ICH has the highest acute mortality and the worst long-term prognosis of all stroke subtypes. Unfortunately, the dearth of clinically effective treatment options makes ICH the least treatable form of stroke, emphasizing the need for novel therapeutic targets. Recent work by our laboratory identified a novel role for the necroptosis inhibitor, necrostatin-1, in limiting neurovascular injury in tissue culture models of hemorrhagic injury. In the present study, we tested the hypothesis that necrostatin-1 reduces neurovascular injury after collagenase-induced ICH in mice. Necrostatin-1 significantly reduced hematoma volume by 54% at 72 h after-ICH, as compared to either sham-injured mice or mice administered an inactive, structural analogue of necrostatin-1. Necrostatin-1 also limited cell death by 48%, reduced blood-brain barrier opening by 51%, attenuated edema development to sham levels, and improved neurobehavioral outcomes after ICH. These data suggest a potential clinical utility for necrostatin-1 and/or novel necroptosis inhibitors as an adjunct therapy to reduce neurological injury and improve patient outcomes after ICH.

12.
J Infect Dis ; 210(6): 899-903, 2014 Sep 15.
Article in English | MEDLINE | ID: mdl-24664171

ABSTRACT

The impact of CD4+ regulatory T cells (Tregs) on human immunodeficiency virus type 1 (HIV-1) pathogenesis remains incompletely understood. Although it has been shown that Tregs can be infected with HIV-1, the consequences of infection on a per-cell basis are still unknown. In vitro HIV-GFP infected and noninfected Tregs were isolated by flow-based cell-sorting to investigate Treg suppressive capacity and gene expression profiles. Our data show that HIV-1-infected Tregs were significantly less suppressive than noninfected Tregs and demonstrated down-regulation of genes critical to Treg function. This impaired function may have detrimental consequences for the control of generalized immune activation and accelerate HIV disease progression.


Subject(s)
HIV Infections/immunology , HIV-1/immunology , T-Lymphocytes, Regulatory/immunology , Down-Regulation , Flow Cytometry , Gene Expression Profiling , Humans , Immunity, Cellular , In Vitro Techniques , T-Lymphocytes, Regulatory/physiology , T-Lymphocytes, Regulatory/virology
13.
PLoS One ; 9(2): e86920, 2014.
Article in English | MEDLINE | ID: mdl-24498287

ABSTRACT

While modulation of regulatory T cell (Treg) function and adoptive Treg transfer are being explored as therapeutic modalities in the context of autoimmune diseases, transplantation and cancer, their role in HIV-1 pathogenesis remains less well defined. Controversy persists regarding their beneficial or detrimental effects in HIV-1 disease, which warrants further detailed exploration. Our objectives were to investigate if functional CD4(+) Tregs can be isolated and expanded from HIV-1-infected individuals for experimental or potential future therapeutic use and to determine phenotype and suppressive capacity of expanded Tregs from HIV-1 positive blood and tissue. Tregs and conventional T cell controls were isolated from blood and gut-associated lymphoid tissue of individuals with HIV-1 infection and healthy donors using flow-based cell-sorting. The phenotype of expanded Tregs was assessed by flow-cytometry and quantitative PCR. T-cell receptor ß-chain (TCR-ß) repertoire diversity was investigated by deep sequencing. Flow-based T-cell proliferation and chromium release cytotoxicity assays were used to determine Treg suppressive function. Tregs from HIV-1 positive individuals, including infants, were successfully expanded from PBMC and GALT. Expanded Tregs expressed high levels of FOXP3, CTLA4, CD39 and HELIOS and exhibited a highly demethylated TSDR (Treg-specific demethylated region), characteristic of Treg lineage. The TCRß repertoire was maintained following Treg expansion and expanded Tregs remained highly suppressive in vitro. Our data demonstrate that Tregs can be expanded from blood and tissue compartments of HIV-1+ donors with preservation of Treg phenotype, function and TCR repertoire. These results are highly relevant for the investigation of potential future therapeutic use, as currently investigated for other disease states and hold great promise for detailed studies on the role of Tregs in HIV-1 infection.


Subject(s)
Cell Proliferation , HIV Infections/immunology , HIV-1/immunology , Receptors, Antigen, T-Cell/immunology , T-Lymphocytes, Regulatory/immunology , Adult , Cells, Cultured , Cytotoxicity, Immunologic/immunology , DNA Methylation/immunology , Female , Flow Cytometry , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/immunology , Forkhead Transcription Factors/metabolism , Gastrointestinal Tract/immunology , Gastrointestinal Tract/virology , Gene Expression/immunology , HIV Infections/blood , HIV Infections/virology , HIV-1/physiology , High-Throughput Nucleotide Sequencing/methods , Host-Pathogen Interactions/immunology , Humans , Immunophenotyping , Infant , Lymphoid Tissue/immunology , Lymphoid Tissue/virology , Male , Middle Aged , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/metabolism , Reverse Transcriptase Polymerase Chain Reaction , T-Lymphocytes, Regulatory/metabolism
14.
J Vis Exp ; (75): e50244, 2013 May 30.
Article in English | MEDLINE | ID: mdl-23748671

ABSTRACT

CD4+ Regulatory T cells (Tregs) are potent immune modulators and serve an important function in human immune homeostasis. Depletion of Tregs has led to measurable increases in antigen-specific T cell responses in vaccine settings for cancer and infectious pathogens. However, their role in HIV-1 immuno-pathogenesis remains controversial, as they could either serve to suppress deleterious HIV-1-associated immune activation and thus slow HIV-1 disease progression or alternatively suppress HIV-1-specific immunity and thereby promote virus spread. Understanding and modulating Treg function in the context of HIV-1 could lead to potential new strategies for immunotherapy or HIV vaccines. However, important open questions remain on their role in the context of HIV-1 infection, which needs to be carefully studied. Representing roughly 5% of human CD4+ T cells in the peripheral blood, studying the Treg population has proven to be difficult, especially in HIV-1 infected individuals where HIV-1-associated CD4 T cell and with that Treg depletion occurs. The characterization of regulatory T cells in individuals with advanced HIV-1 disease or tissue samples, for which only very small biological samples can be obtained, is therefore extremely challenging. We propose a technical solution to overcome these limitations using isolation and expansion of Tregs from HIV-1-positive individuals. Here we describe an easy and robust method to successfully expand Tregs isolated from HIV-1-infected individuals in vitro. Flow-sorted CD3(+)CD4(+)CD25(+)CD127(low) Tregs were stimulated with anti-CD3/anti-CD28 coated beads and cultured in the presence of IL-2. The expanded Tregs expressed high levels of FOXP3, CTLA4 and HELIOS compared to conventional T cells and were shown to be highly suppressive. Easier access to large numbers of Tregs will allow researchers to address important questions concerning their role in HIV-1 immunopathogenesis. We believe answering these questions may provide useful insight for the development of an effective HIV-1 vaccine.


Subject(s)
Cytological Techniques/methods , HIV Infections/blood , HIV-1 , T-Lymphocytes, Regulatory/cytology , HIV Infections/immunology , Humans , Lymphocyte Activation , T-Lymphocytes, Regulatory/immunology
15.
Neurosci Lett ; 542: 92-6, 2013 May 10.
Article in English | MEDLINE | ID: mdl-23499961

ABSTRACT

Intracerebral hemorrhage (ICH), the most common form of hemorrhagic stroke, exhibits the highest acute mortality and the worst long-term prognosis of all stroke subtypes. Unfortunately, treatment options for ICH are lacking due in part to a lack of feasible therapeutic targets. Inflammatory activation is associated with neurological deficits in pre-clinical ICH models and with patient deterioration after clinical ICH. In the present study, we tested the hypothesis that R-7050, a novel cell permeable triazoloquinoxaline inhibitor of the tumor necrosis factor receptor (TNFR) complex, attenuates neurovascular injury after ICH in mice. Up to 2h post-injury administration of R-7050 significantly reduced blood-brain barrier opening and attenuated edema development at 24h post-ICH. Neurological outcomes were also improved over the first 3 days after injury. In contrast, R-7050 did not reduce hematoma volume, suggesting the beneficial effects of TNFR inhibition were downstream of clot formation/resolution. These data suggest a potential clinical utility for TNFR antagonists as an adjunct therapy to reduce neurological injury and improve patient outcomes after ICH.


Subject(s)
Brain/drug effects , Cerebral Hemorrhage/drug therapy , Neuroprotective Agents/pharmacology , Quinoxalines/pharmacology , Receptors, Tumor Necrosis Factor, Type I/antagonists & inhibitors , Triazoles/pharmacology , Tumor Necrosis Factor-alpha/metabolism , Animals , Blood-Brain Barrier/metabolism , Brain/metabolism , Brain/pathology , Brain Edema/drug therapy , Brain Edema/pathology , Cerebral Hemorrhage/pathology , Cerebral Hemorrhage/physiopathology , Hematoma/drug therapy , Hematoma/pathology , Male , Mice , Neuroprotective Agents/therapeutic use , Quinoxalines/therapeutic use , Triazoles/therapeutic use
16.
AIDS ; 26(16): 2112-5, 2012 Oct 23.
Article in English | MEDLINE | ID: mdl-22874519

ABSTRACT

Regulatory T cells (Tregs) are potent immune modulators, but their precise role in HIV pathogenesis remains incompletely understood. Most studies to date have focused on frequencies or phenotypes of 'bulk' Treg populations. However, although antigen-specific Tregs have been reported in other diseases, HIV-1 epitope-specific Tregs have not been described to date. We here report the first identification of functional HIV-1-Gag-specific regulatory T cells using human leukocyte antigen class II tetramer staining in HIV-1-infected individuals.


Subject(s)
HIV-1/immunology , HLA Antigens/immunology , Histocompatibility Antigens Class II/immunology , T-Lymphocytes, Regulatory/immunology , Epitopes/immunology , Female , HIV Infections/immunology , Humans , Male , gag Gene Products, Human Immunodeficiency Virus/metabolism , pol Gene Products, Human Immunodeficiency Virus/metabolism
17.
J Infect Dis ; 205(10): 1495-500, 2012 May 15.
Article in English | MEDLINE | ID: mdl-22427677

ABSTRACT

Regulatory T cells (Tregs) are potent immune modulators, but their role in human immunodeficiency virus type 1 (HIV-1) pathogenesis remains poorly understood. We performed a detailed analysis of the frequency and function of Tregs in a large cohort of HIV-1-infected individuals and HIV-1 negative controls. While HIV "elite controllers" and uninfected individuals had similar Treg numbers and frequencies, the absolute numbers of Tregs declined in blood and gut-associated lymphoid tissue in patients with chronic progressive HIV-1 infection. Despite quantitative changes in Tregs, HIV-1 infection was not associated with an impairment of ex vivo suppressive function of flow-sorted Tregs in both HIV controllers and untreated chronic progressors.


Subject(s)
HIV Infections/immunology , HIV-1/immunology , T-Lymphocytes, Regulatory/physiology , Case-Control Studies , Chronic Disease , Cohort Studies , Disease Progression , Flow Cytometry , HIV Infections/virology , Humans , Lymphocyte Count , Lymphoid Tissue/immunology , RNA, Viral/blood , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/virology , Viral Load
19.
J Neurosurg ; 115(1): 116-23, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21417704

ABSTRACT

OBJECT: Intracerebral hemorrhage (ICH) is associated with significant morbidity and mortality. Acute hematoma enlargement is an important predictor of neurological injury and poor clinical prognosis; but neurosurgical clot evacuation may not be feasible in all patients and treatment options remain largely supportive. Thus, novel therapeutic approaches to promote hematoma resolution are needed. In the present study, the authors investigated whether the curry spice curcumin limited neurovascular injury following ICH in mice. METHODS: Intracerebral hemorrhage was induced in adult male CD-1 mice by intracerebral administration of collagenase or autologous blood. Clinically relevant doses of curcumin (75-300 mg/kg) were administered up to 6 hours after ICH, and hematoma volume, inflammatory gene expression, blood-brain barrier permeability, and brain edema were assessed over the first 72 hours. Neurological assessments were performed to correlate neurovascular protection with functional outcomes. RESULTS: Curcumin increased hematoma resolution at 72 hours post-ICH. This effect was associated with a significant reduction in the expression of the proinflammatory mediators, tumor necrosis factor-α, interleukin-6, and interleukin-1ß. Curcumin also reduced disruption of the blood-brain barrier and attenuated the formation of vasogenic edema following ICH. Consistent with the reduction in neuroinflammation and neurovascular injury, curcumin significantly improved neurological outcome scores after ICH. CONCLUSIONS: Curcumin promoted hematoma resolution and limited neurological injury following ICH. These data may indicate clinical utility for curcumin as an adjunct therapy to reduce brain injury and improve patient outcome.


Subject(s)
Cerebral Hemorrhage/pathology , Curcumin/pharmacology , Enzyme Inhibitors/pharmacology , Hematoma/drug therapy , Hematoma/pathology , Animals , Blood-Brain Barrier/drug effects , Brain Edema/drug therapy , Disease Models, Animal , Hematoma/etiology , Interleukin-1beta/metabolism , Interleukin-6/metabolism , Male , Mice , Mice, Inbred Strains , Treatment Outcome , Tumor Necrosis Factor-alpha/metabolism
20.
Neurosurg Focus ; 28(1): E10, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20043714

ABSTRACT

Subarachnoid hemorrhage (SAH) is a devastating neurological injury associated with significant patient morbidity and death. Since the first demonstration of cerebral vasospasm nearly 60 years ago, the preponderance of research has focused on strategies to limit arterial narrowing and delayed cerebral ischemia following SAH. However, recent clinical and preclinical data indicate a functional dissociation between cerebral vasospasm and neurological outcome, signaling the need for a paradigm shift in the study of brain injury following SAH. Early brain injury may contribute to poor outcome and early death following SAH. However, elucidation of the complex cellular mechanisms underlying early brain injury remains a major challenge. The advent of modern neuroproteomics has rapidly advanced scientific discovery by allowing proteome-wide screening in an objective, nonbiased manner, providing novel mechanisms of brain physiology and injury. In the context of neurosurgery, proteomic analysis of patient-derived CSF will permit the identification of biomarkers and/or novel drug targets that may not be intuitively linked with any particular disease. In the present report, the authors discuss the utility of neuroproteomics with a focus on the roles for this technology in understanding SAH. The authors also provide data from our laboratory that identifies high-mobility group box protein-1 as a potential biomarker of neurological outcome following SAH in humans.


Subject(s)
Brain/physiopathology , Proteome/physiology , Proteomics/methods , Subarachnoid Hemorrhage/physiopathology , Biomarkers/analysis , Biomarkers/cerebrospinal fluid , Forecasting , HMGB1 Protein/genetics , HMGB1 Protein/physiology , Humans , Intracranial Aneurysm/cerebrospinal fluid , Intracranial Aneurysm/genetics , Intracranial Aneurysm/physiopathology , Neurosurgery , Proteomics/trends , Stroke/physiopathology , Subarachnoid Hemorrhage/cerebrospinal fluid , Subarachnoid Hemorrhage/surgery , Treatment Outcome , Vasospasm, Intracranial/physiopathology
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