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1.
N Engl J Med ; 388(2): 128-141, 2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-36516086

RESUMO

BACKGROUND: The late-onset cerebellar ataxias (LOCAs) have largely resisted molecular diagnosis. METHODS: We sequenced the genomes of six persons with autosomal dominant LOCA who were members of three French Canadian families and identified a candidate pathogenic repeat expansion. We then tested for association between the repeat expansion and disease in two independent case-control series - one French Canadian (66 patients and 209 controls) and the other German (228 patients and 199 controls). We also genotyped the repeat in 20 Australian and 31 Indian index patients. We assayed gene and protein expression in two postmortem cerebellum specimens and two induced pluripotent stem-cell (iPSC)-derived motor-neuron cell lines. RESULTS: In the six French Canadian patients, we identified a GAA repeat expansion deep in the first intron of FGF14, which encodes fibroblast growth factor 14. Cosegregation of the repeat expansion with disease in the families supported a pathogenic threshold of at least 250 GAA repeats ([GAA]≥250). There was significant association between FGF14 (GAA)≥250 expansions and LOCA in the French Canadian series (odds ratio, 105.60; 95% confidence interval [CI], 31.09 to 334.20; P<0.001) and in the German series (odds ratio, 8.76; 95% CI, 3.45 to 20.84; P<0.001). The repeat expansion was present in 61%, 18%, 15%, and 10% of French Canadian, German, Australian, and Indian index patients, respectively. In total, we identified 128 patients with LOCA who carried an FGF14 (GAA)≥250 expansion. Postmortem cerebellum specimens and iPSC-derived motor neurons from patients showed reduced expression of FGF14 RNA and protein. CONCLUSIONS: A dominantly inherited deep intronic GAA repeat expansion in FGF14 was found to be associated with LOCA. (Funded by Fondation Groupe Monaco and others.).


Assuntos
Ataxia Cerebelar , Expansão das Repetições de DNA , Íntrons , Humanos , Austrália , Canadá , Ataxia Cerebelar/genética , Ataxia Cerebelar/patologia , Ataxia de Friedreich/genética , Ataxia de Friedreich/patologia , Íntrons/genética , Expansão das Repetições de DNA/genética
2.
Neuroimage ; 266: 119828, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36549431

RESUMO

The midbrain periaqueductal grey (PAG) is a critical region for the mediation of pain-related behavioural responses. Neuronal tract tracing techniques in experimental animal studies have demonstrated that the lateral column of the PAG (lPAG) displays a crude somatotopy, which is thought to be critical for the selection of contextually appropriate behavioural responses, without the need for higher brain input. In addition to the different behavioural responses to cutaneous and muscle pain - active withdrawal versus passive coping - there is evidence that cutaneous pain is processed in the region of the lPAG and muscle pain in the adjacent ventrolateral PAG (vlPAG). Given the fundamental nature of these behavioural responses to cutaneous and muscle pain, these PAG circuits are assumed to have been preserved, though yet to be definitively documented in humans. Using ultra-high field (7-Tesla) functional magnetic resonance imaging we determined the locations of signal intensity changes in the PAG during noxious cutaneous heat stimuli and muscle pain in healthy control participants. Images were processed and blood oxygen level dependant (BOLD) signal changes within the PAG determined. It was observed that noxious cutaneous stimulation of the lip, cheek, and ear evoked maximal increases in BOLD activation in the rostral contralateral PAG, whereas noxious cutaneous stimulation of the thumb and toe evoked increases in the caudal contralateral PAG. Analysis of individual participants demonstrated that these activations were located in the lPAG. Furthermore, we found that deep muscular pain evoked the greatest increases in signal intensity in the vlPAG. These data suggest that the crude somatotopic organization of the PAG may be phyletically preserved between experimental animals and humans, with a body-face delineation capable of producing an appropriate behavioural response based on the location and tissue origin of a noxious stimulus.


Assuntos
Mialgia , Substância Cinzenta Periaquedutal , Animais , Humanos , Substância Cinzenta Periaquedutal/fisiologia , Neurônios , Comportamento Animal/fisiologia , Imageamento por Ressonância Magnética
3.
Neuroimage ; 259: 119408, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35752415

RESUMO

Over the past two decades, magnetic resonance imaging (MRI) studies have explored brain activation patterns during acute noxious stimuli. Whilst these human investigations have detailed changes in primarily cortical regions, they have generally not explored discrete changes within small brain areas that are critical in driving behavioural, autonomic, and endocrine responses to pain, such as within subregions of the hypothalamus, amygdala, and midbrain periaqueductal gray matter (PAG). Ultra-high field (7-Tesla) MRI provides enough signal-to-noise at high spatial resolutions to investigate activation patterns within these small brain regions during acute noxious stimulation in awake humans. In this study we used 7T functional MRI to concentrate on hypothalamic, amygdala, and PAG signal changes during acute noxious orofacial stimuli. Noxious heat stimuli were applied in three separate fMRI scans to three adjacent sites on the face in 16 healthy control participants (7 females). Images were processed using SPM12 and custom software, and blood oxygen level dependent signal changes within the hypothalamus, amygdala, and PAG assessed. We identified altered activity within eight unique subregions of the hypothalamus, four unique subregions of the amygdala, and a single region in the lateral PAG. Specifically, within the hypothalamus and amygdala, signal intensity largely decreased during noxious stimulation, and increased in the lateral PAG. Furthermore, we found sex-related differences in discrete regions of the hypothalamus and amygdala. This study reveals that the activity of discrete nuclei during acute noxious thermal stimulation in awake humans.


Assuntos
Dor Aguda , Substância Cinzenta Periaquedutal , Tonsila do Cerebelo/diagnóstico por imagem , Feminino , Humanos , Hipotálamo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Substância Cinzenta Periaquedutal/diagnóstico por imagem , Substância Cinzenta Periaquedutal/fisiologia , Vigília
4.
Haematologica ; 107(8): 1786-1795, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35142149

RESUMO

Less than a third of patients with acute myeloid leukemia (AML) are cured by chemotherapy and/or hematopoietic stem cell transplantation, highlighting the need to develop more efficient drugs. The low efficacy of standard treatments is associated with inadequate depletion of CD34+ blasts and leukemic stem cells, the latter a drug-resistant subpopulation of leukemia cells characterized by the CD34+CD38- phenotype. To target these drug-resistant primitive leukemic cells better, we have designed a CD34/CD3 bi-specific T-cell engager (BTE) and characterized its anti-leukemia potential in vitro, ex vivo and in vivo. Our results show that this CD34-specific BTE induces CD34-dependent T-cell activation and subsequent leukemia cell killing in a dose-dependent manner, further corroborated by enhanced T-cell-mediated killing at the singlecell level. Additionally, the BTE triggered efficient T-cell-mediated depletion of CD34+ hematopoietic stem cells from peripheral blood stem cell grafts and CD34+ blasts from AML patients. Using a humanized AML xenograft model, we confirmed that the CD34-specific BTE had in vivo efficacy by depleting CD34+ blasts and leukemic stem cells without side effects. Taken together, these data demonstrate that the CD34-specific BTE has robust antitumor effects, supporting development of a novel treatment modality with the aim of improving outcomes of patients with AML and myelodysplastic syndromes.


Assuntos
Leucemia Mieloide Aguda , Células-Tronco Neoplásicas , Antígenos CD34 , Moléculas de Adesão Celular , Humanos , Imunofenotipagem , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/terapia , Células-Tronco Neoplásicas/patologia , Linfócitos T/patologia
5.
Am J Pathol ; 190(3): 554-562, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31953038

RESUMO

BCL-2-associated athanogene 3 (BAG3) is a co-chaperone to heat shock proteins important in degrading misfolded proteins through chaperone-assisted selective autophagy. The recurrent dominant BAG3-P209L mutation results in a severe childhood-onset myofibrillar myopathy (MFM) associated with progressive muscle weakness, cardiomyopathy, and respiratory failure. Because a homozygous knock-in (KI) strain for the mP215L mutation homologous to the human P209L mutation did not have a gross phenotype, compound heterozygote knockout (KO) and KI mP215L mice were generated to establish whether further reduction in BAG3 expression would lead to a phenotype. The KI/KO mice have a significant decrease in voluntary movement compared with wild-type and KI/KI mice in the open field starting at 7 months. The KI/KI and KI/KO mice both have significantly smaller muscle fiber cross-sectional area. However, only the KI/KO mice have clear skeletal muscle histologic changes in MFM. As in patient muscle, there are increased levels of BAG3-interacting proteins, such as p62, heat shock protein B8, and αB-crystallin. The KI/KO mP215L strain is the first murine model of BAG3 myopathy that resembles the human skeletal muscle pathologic features. The results support the hypothesis that the pathologic development of MFM requires a significant decrease in BAG3 protein level and not only a gain of function caused by the dominant missense mutation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose/genética , Miopatias Congênitas Estruturais/patologia , Animais , Cardiomiopatias/genética , Cardiomiopatias/patologia , Modelos Animais de Doenças , Genes Dominantes , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/patologia , Mutação , Miopatias Congênitas Estruturais/genética , Fenótipo
6.
Ann Neurol ; 87(4): 568-583, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31970803

RESUMO

OBJECTIVE: Recessive null variants of the slow skeletal muscle troponin T1 (TNNT1) gene are a rare cause of nemaline myopathy that is fatal in infancy due to respiratory insufficiency. Muscle biopsy shows rods and fiber type disproportion. We report on 4 French Canadians with a novel form of recessive congenital TNNT1 core-rod myopathy. METHODS: Patients underwent full clinical characterization, lower limb magnetic resonance imaging (MRI), muscle biopsy, and genetic testing. A zebrafish loss-of-function model using morpholinos was created to assess the pathogenicity of the identified variant. Wild-type or mutated human TNNT1 mRNAs were coinjected with morpholinos to assess their abilities to rescue the morphant phenotype. RESULTS: Three adults and 1 child shared a novel missense homozygous variant in the TNNT1 gene (NM_003283.6: c.287T > C; p.Leu96Pro). They developed from childhood very slowly progressive limb-girdle weakness with rigid spine and disabling contractures. They suffered from restrictive lung disease requiring noninvasive mechanical ventilation in 3 patients, as well as recurrent episodes of rhabdomyolysis triggered by infections, which were relieved by dantrolene in 1 patient. Older patients remained ambulatory into their 60s. MRI of the leg muscles showed fibrofatty infiltration predominating in the posterior thigh and the deep posterior leg compartments. Muscle biopsies showed multiminicores and lobulated fibers, rods in half the patients, and no fiber type disproportion. Wild-type TNNT1 mRNA rescued the zebrafish morphants, but mutant transcripts failed to do so. INTERPRETATION: This study expands the phenotypic spectrum of TNNT1 myopathy and provides functional evidence for the pathogenicity of the newly identified missense mutation. ANN NEUROL 2020;87:568-583.


Assuntos
Músculo Esquelético/patologia , Miopatias da Nemalina/fisiopatologia , RNA Mensageiro/metabolismo , Troponina T/genética , Animais , Criança , Feminino , Técnicas de Silenciamento de Genes , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Morfolinos , Músculo Esquelético/ultraestrutura , Miopatias da Nemalina/genética , Miopatias da Nemalina/patologia , Rabdomiólise/genética , Rabdomiólise/fisiopatologia , Troponina T/metabolismo , Peixe-Zebra
7.
BMC Health Serv Res ; 21(1): 567, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34107941

RESUMO

BACKGROUND: Healthcare practitioners (HCPs) play a crucial role in recognising, responding to, and supporting female patients experiencing intimate partner abuse (IPA). However, research consistently identifies barriers they perceive prevent them from doing this work effectively. These barriers can be system-based (e.g. lack of time or training) or personal/individual. This review of qualitative evidence aims to synthesise the personal barriers that impact HCPs' responses to IPA. METHODS: Five databases were searched in March 2020. Studies needed to utilise qualitative methods for both data collection and analysis and be published between 2010 and 2020 in order to qualify for inclusion; however, we considered any type of healthcare setting in any country. Article screening, data extraction and methodological appraisal using a modified version of the Critical Appraisal Skills Program checklist for qualitative studies were undertaken by at least two independent reviewers. Data analysis drew on Thomas and Harden's thematic synthesis approach. RESULTS: Twenty-nine studies conducted in 20 countries informed the final review. A variety of HCPs and settings were represented. Three themes were developed that describe the personal barriers experienced by HCPs: I can't interfere (which describes the belief that IPA is a "private matter" and HCPs' fears of causing harm by intervening); I don't have control (highlighting HCPs' frustration when women do not follow their advice); and I won't take responsibility (which illuminates beliefs that addressing IPA should be someone else's job). CONCLUSION: This review highlights the need for training to address personal issues in addition to structural or organisational barriers. Education and training for HCPs needs to: encourage reflection on their own values to reinforce their commitment to addressing IPA; teach HCPs to relinquish the need to control outcomes so that they can adopt an advocacy approach; and support HCPs' trust in the critical role they can play in responding. Future research should explore effective ways to do this within the context of complex healthcare organisations.


Assuntos
Pessoal de Saúde , Violência por Parceiro Íntimo , Atenção à Saúde , Feminino , Instalações de Saúde , Humanos , Violência por Parceiro Íntimo/prevenção & controle , Pesquisa Qualitativa
8.
Conserv Biol ; 32(6): 1457-1463, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29923638

RESUMO

In 2008, a group of conservation scientists compiled a list of 100 priority questions for the conservation of the world's biodiversity. However, now almost a decade later, no one has yet published a study gauging how much progress has been made in addressing these 100 high-priority questions in the peer-reviewed literature. We took a first step toward reexamining the 100 questions to identify key knowledge gaps that remain. Through a combination of a questionnaire and a literature review, we evaluated each question on the basis of 2 criteria: relevance and effort. We defined highly relevant questions as those that - if answered - would have the greatest impact on global biodiversity conservation and quantified effort based on the number of review publications addressing a particular question, which we used as a proxy for research effort. Using this approach, we identified a set of questions that, despite being perceived as highly relevant, have been the focus of relatively few review publications over the past 10 years. These questions covered a broad range of topics but predominantly tackled 3 major themes: conservation and management of freshwater ecosystems, role of societal structures in shaping interactions between people and the environment, and impacts of conservation interventions. We believe these questions represent important knowledge gaps that have received insufficient attention and may need to be prioritized in future research.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Água Doce
9.
BMC Infect Dis ; 16(1): 504, 2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27659198

RESUMO

BACKGROUND: To determine the distribution of Human leukocyte antigen (HLA) class I genotypes in a Ugandan population of persons with tuberculosis (TB) and establish the relationship between class I HLA types and Mycobacterium tuberculosis (MTB) disease. METHODS: Blood samples were drawn from HIV negative individuals with active TB and HIV negative household controls. DNA was extracted from blood samples and HLA typed by the polymerase chain reaction-sequence specific primer method. The allelic frequencies were determined by direct count. RESULTS: HLA-A*02, B*15, C*07, C*03, B*58, C*04, A*01, A*74, C*02 and A*30 were the dominant genotypes in this Ugandan cohort. There were differences in the distribution of HLA types between the individuals with active TB and the household controls with only HLA-A*03 allele showing a statistically significant difference (p = 0.017 crude; OR = 6.29 and p = 0.016; OR = 11.67 after adjustment for age). However, after applying the Benjamini and Hochberg adjustment for multiple comparisons the difference was no longer statistically significant (p = 0.374 and p = 0.176 respectively). CONCLUSIONS: We identified a number of HLA class I alleles in a population from Central Uganda which will enable us to carry out a functional characterization of CD8+ T-cell mediated immune responses to MTB. Our results do not show a positive association between the HLA class I alleles and TB in this Ugandan population however the study sample was too small to draw any firm conclusions about the role of HLA class I alleles and TB development in Uganda.

10.
BMC Infect Dis ; 14: 319, 2014 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-24916787

RESUMO

BACKGROUND: Previous exposures to flu and subsequent immune responses may impact on 2009/2010 pandemic flu vaccine responses and clinical symptoms upon infection with the 2009 pandemic H1N1 influenza strain. Qualitative and quantitative differences in humoral and cellular immune responses associated with the flu vaccination in 2009/2010 (pandemic H1N1 vaccine) and natural infection have not yet been described in detail. We designed a longitudinal study to examine influenza- (flu-) specific immune responses and the association between pre-existing flu responses, symptoms of influenza-like illness (ILI), impact of pandemic flu infection, and pandemic flu vaccination in a cohort of 2,040 individuals in Sweden in 2009-2010. METHODS: Cellular flu-specific immune responses were assessed by whole-blood antigen stimulation assay, and humoral responses by a single radial hemolysis test. RESULTS: Previous seasonal flu vaccination was associated with significantly lower flu-specific IFN-γ responses (using a whole-blood assay) at study entry. Pandemic flu vaccination induced long-lived T-cell responses (measured by IFN-γ production) to influenza A strains, influenza B strains, and the matrix (M1) antigen. In contrast, individuals with pandemic flu infection (PCR positive) exhibited increased flu-specific T-cell responses shortly after onset of ILI symptoms but the immune response decreased after the flu season (spring 2010). We identified non-pandemic-flu vaccinated participants without ILI symptoms who showed an IFN-γ production profile similar to pandemic-flu infected participants, suggesting exposure without experiencing clinical symptoms. CONCLUSIONS: Strong and long-lived flu-M1 specific immune responses, defined by IFN-γ production, in individuals after vaccination suggest that M1-responses may contribute to protective cellular immune responses. Silent flu infections appeared to be frequent in 2009/2010. The pandemic flu vaccine induced qualitatively and quantitatively different humoral and cellular immune responses as compared to infection with the 2009 H1N1 pandemic H1N1 influenza strain.


Assuntos
Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Adolescente , Adulto , Idoso , Anticorpos Antivirais/sangue , Feminino , Humanos , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H1N1/patogenicidade , Influenza Humana/epidemiologia , Interferon gama/metabolismo , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Suécia/epidemiologia , Linfócitos T/imunologia , Vacinação , Adulto Jovem
11.
Curr Top Dev Biol ; 158: 83-121, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38670717

RESUMO

Muscle stem cells (MuSCs) are crucial to the repair and homeostasis of mature skeletal muscle. MuSC dysfunction and dysregulation of the myogenic program can contribute to the development of pathology ranging from cancers like rhabdomyosarcoma (RMS) or muscle degenerative diseases such as Duchenne muscular dystrophy (DMD). Both diseases exhibit dysregulation at nearly all steps of myogenesis. For instance, MuSC self-renewal processes are altered. In RMS, this leads to the creation of tumor propagating cells. In DMD, impaired asymmetric stem cell division creates a bias towards producing self-renewing stem cells instead of committing to differentiation. Hyperproliferation of these cells contribute to tumorigenesis in RMS and symmetric expansion of the self-renewing MuSC population in DMD. Both diseases also exhibit a repression of factors involved in terminal differentiation, halting RMS cells in the proliferative stage and thus driving tumor growth. Conversely, the MuSCs in DMD exhibit impaired differentiation and fuse prematurely, affecting myonuclei maturation and the integrity of the dystrophic muscle fiber. Finally, both disease states cause alterations to the MuSC niche. Various elements of the niche such as inflammatory and migratory signaling that impact MuSC behavior are dysregulated. Here we show how these seemingly distantly related diseases indeed have similarities in MuSC dysfunction, underlying the importance of considering MuSCs when studying the pathophysiology of muscle diseases.


Assuntos
Rabdomiossarcoma , Rabdomiossarcoma/patologia , Humanos , Animais , Músculo Esquelético/patologia , Diferenciação Celular , Distrofia Muscular de Duchenne/patologia , Distrofia Muscular de Duchenne/fisiopatologia , Desenvolvimento Muscular , Células-Tronco/citologia , Distrofias Musculares/patologia
12.
J Infect Dis ; 205 Suppl 2: S301-15, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22448020

RESUMO

Aerosols containing Mycobacterium tuberculosis (MTB) generated from the cough of patients with active pulmonary tuberculosis are the source of MTB infection. About 70% of individuals exposed to infected aerosols do not get infected, depending on the intensity and duration of MTB exposure. Only 40% of the rest of the individuals (about 10% of those originally exposed) develop primary tuberculosis, whereas the remaining 60% contain the infection with generation of a robust immune response leading to latent tuberculosis, which is regarded as a spectrum rather than a single entity. The mechanisms involved in this natural protection are not yet well understood. There is an increasing need to integrate all disparate observations into a coherent systems biology approach for a comprehensive understanding: we need to decipher the nature of success and failure in MTB infection in humans. New advances in cellular immunology will aid in achieving that goal. We review here the nature of MTB peptide generation, antigen presentation, and detection of major histocompatibility complex class I and II-presented T-cell epitopes. Cross-sectional thinking from lessons learned in the context of the major efforts to develop vaccines will help to dissect biologically relevant mechanisms that need to be translated into the clinical context of MTB infection with the aim to (1) better understand clinically relevant T-cell responses in individuals protected from tuberculosis disease and develop markers of immune protection and vaccine take, (2) characterize the nature of the immune response in individuals who are not able to contain MTB infection, and ultimately (3) characterize markers to gauge response to therapy.


Assuntos
Epitopos de Linfócito T/imunologia , Mycobacterium tuberculosis/imunologia , Vacinas contra a Tuberculose/imunologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologia , Biomarcadores , Humanos
13.
PLoS One ; 18(1): e0262792, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36701399

RESUMO

Tau becomes abnormally hyper-phosphorylated and aggregated in tauopathies like Alzheimers disease (AD). As age is the greatest risk factor for developing AD, it is important to understand how tau protein itself, and the pathways implicated in its turnover, change during aging. We investigated age-related changes in total and phosphorylated tau in brain samples from two cohorts of cognitively normal individuals spanning 19-74 years, without overt neurodegeneration. One cohort utilised resected tissue and the other used post-mortem tissue. Total soluble tau levels declined with age in both cohorts. Phosphorylated tau was undetectable in the post-mortem tissue but was clearly evident in the resected tissue and did not undergo significant age-related change. To ascertain if the decline in soluble tau was correlated with age-related changes in autophagy, three markers of autophagy were tested but only two appeared to increase with age and the third was unchanged. This implies that in individuals who do not develop neurodegeneration, there is an age-related reduction in soluble tau which could potentially be due to age-related changes in autophagy. Thus, to explore how an age-related increase in autophagy might influence tau-mediated dysfunctions in vivo, autophagy was enhanced in a Drosophila model and all age-related tau phenotypes were significantly ameliorated. These data shed light on age-related physiological changes in proteins implicated in AD and highlights the need to study pathways that may be responsible for these changes. It also demonstrates the therapeutic potential of interventions that upregulate turnover of aggregate-prone proteins during aging.


Assuntos
Doença de Alzheimer , Tauopatias , Animais , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Proteínas tau/metabolismo , Tauopatias/metabolismo , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Drosophila/metabolismo , Autofagia/genética , Fosforilação
14.
Immunology ; 129(4): 496-505, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20002212

RESUMO

The molecular definition of major histocompatibility complex (MHC) class I-presented CD8(+) T-cell epitopes from clinically relevant Mycobacterium tuberculosis (Mtb) target proteins will aid in the rational design of T-cell-based diagnostics of tuberculosis (TB) and the measurement of TB vaccine-take. We used an epitope discovery system, based on recombinant MHC class I molecules that cover the most frequent Caucasian alleles [human leucocyte antigen (HLA)-A*0101, A*0201, A*0301, A*1101, A*2402, B*0702, B*0801 and B*1501], to identify MHC class I-binding peptides from overlapping 9-mer peptides representing the Mtb protein TB10.4. A total of 33 MHC class I-binding epitopes were identified, spread across the entire amino acid sequence, with some clustering at the N- and C-termini of the protein. Binding of individual peptides or closely related peptide species to different MHC class I alleles was frequently observed. For instance, the common motif of xIMYNYPAMx bound to six of eight alleles. Affinity (50% effective dose) and off-rate (half life) analysis of candidate Mtb peptides will help to define the conditions for CD8(+) T-cell interaction with their nominal MHC class I-peptide ligands. Subsequent construction of tetramers allowed us to confirm the recognition of some of the epitopes by CD8(+) T cells from patients with active pulmonary TB. HLA-B alleles served as the dominant MHC class I restricting molecules for anti-Mtb TB10.4-specific CD8(+) T-cell responses measured in CD8(+) T cells from patients with pulmonary TB.


Assuntos
Alelos , Linfócitos T CD8-Positivos/imunologia , Antígenos HLA-B/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Mycobacterium tuberculosis/imunologia , Peptídeos/imunologia , Sítios de Ligação , Antígeno HLA-B7 , Antígeno HLA-B8 , Humanos , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/imunologia
15.
Front Immunol ; 9: 760, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29692783

RESUMO

Virus-specific T-cell responses are crucial to control cytomegalovirus (CMV) infections/reactivation in immunocompromised individuals. Adoptive cellular therapy with CMV-specific T-cells has become a viable treatment option. High-affinity anti-viral cellular immune responses are associated with improved long-term immune protection against CMV infection. To date, the characterization of high-affinity T-cell responses against CMV has not been achieved in blood from patients after allogeneic hematopoietic stem cell transplantation (HSCT). Therefore, the purpose of this study was to describe and analyze the phenotype and clinical impact of different CMV-specific CD8+ cytotoxic T-lymphocytes (CMV-CTL) classes based on their T-cell receptor (TCR) affinity. T-cells isolated from 23 patients during the first year following HSCT were tested for the expression of memory markers, programmed cell death 1 (PD-1), as well as TCR affinity, using three different HLA-A*02:01 CMVNLVPMVATV-Pp65 tetramers (wild-type, a245v and q226a mutants). High-affinity CMV-CTL defined by q226a tetramer binding, exhibited a higher frequency in CD8+ T-cells in the first month post-HSCT and exhibited an effector memory phenotype associated with strong PD-1 expression as compared to the medium- and low-affinity CMV-CTLs. High-affinity CMV-CTL was found at higher proportion in patients with chronic graft-versus-host disease (p < 0.001). This study provides a first insight into the detailed TCR affinities of CMV-CTL. This may be useful in order to improve current immunotherapy protocols using isolation of viral-specific T-cell populations based on their TCR affinity.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por Citomegalovirus/imunologia , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/virologia , Transplante de Células-Tronco Hematopoéticas , Citomegalovirus , Humanos , Hospedeiro Imunocomprometido/imunologia , Fenótipo , Receptores de Antígenos de Linfócitos T/imunologia
16.
Conserv Lett ; 11(5): e12564, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31031821

RESUMO

Conservation policy decisions can suffer from a lack of evidence, hindering effective decision-making. In nature conservation, studies investigating why policy is often not evidence-informed have tended to focus on Western democracies, with relatively small samples. To understand global variation and challenges better, we established a global survey aimed at identifying top barriers and solutions to the use of conservation science in policy. This obtained the views of 758 people in policy, practice, and research positions from 68 countries across six languages. Here we show that, contrary to popular belief, there is agreement between groups about how to incorporate conservation science into policy, and there is thus room for optimism. Barriers related to the low priority of conservation were considered to be important, while mainstreaming conservation was proposed as a key solution. Therefore, priorities should focus on convincing the public of the importance of conservation as an issue, which will then influence policy-makers to adopt pro-environmental long-term policies.

17.
Oncoimmunology ; 6(2): e1252894, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28344863

RESUMO

Tumor-infiltrating lymphocytes (TILs) may represent a viable source of T cells for the biological treatment of patients with gliomas. Glioma tissue was obtained from 16 patients, tumor cell lines were established, and TILs were expanded in 16/16 cases using a combination of IL-2/IL-15/IL-21. Intracellular cytokine staining (ICS, IL-2, IL-17, TNFα and IFNγ production) as well as a cytotoxicity assay was used to detect TIL reactivity against autologous tumor cells or shared tumor-associated antigens (TAAs; i.e., NY-ESO-1, Survivin or EGFRvIII). TILs were analyzed by flow cytometry, including T-cell receptor (TCR) Vß family composition, exhaustion/activation and T-cell differentiation markers (CD45RA/CCR7). IL-2/IL-15/IL-21 expanded TILs exhibited a mixture of CD4+, CD8+, as well as CD3+ CD4-CD8- T cells with a predominant central memory CD45RA-CCR7+ phenotype. TIL showed low frequencies of T cells testing positive for PD-1, TIM-3 and CTLA-4. LAG3 tested positive in up to 30% of CD8+ TIL, with low (1.25%) frequencies in CD4+ T cells. TIL cultures exhibited preferential usage of Vß families and recognition of autologous tumor cells defined by cytokine production and cytotoxicity. IL-2/IL-15/IL-21 expanded TILs represent a viable source for the cellular therapy of patients with gliomas.

18.
Int J Infect Dis ; 56: 140-154, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28161459

RESUMO

BACKGROUND: Bacille Calmette-Guérin (BCG) is the world's most widely distributed vaccine, used against tuberculosis (TB), in cancer immunotherapy, and in autoimmune diseases due to its immunomodulatory properties. To date, the effect of BCG vaccination on antibody responses to host proteins has not been reported. High-content peptide microarrays (HCPM) offer a unique opportunity to gauge specific humoral immune responses. METHODS: The sera of BCG-vaccinated healthy adults were tested on a human HCPM platform (4953 randomly selected epitopes of human proteins) to detect specific immunoglobulin gamma (IgG) responses. Samples were obtained at 56, 112, and 252 days after vaccination. Immunohistology was performed on lymph node tissue from patients with TB lymphadenitis. Results were analysed with a combination of existing and novel statistical methods. RESULTS: IgG recognition of host peptides exhibited a peak at day 56 post BCG vaccination in all study subjects tested, which diminished over time. Primarily, IgG responses exhibited increased reactivity to ion transporters (sodium, calcium channels), cytokine receptors (interleukin 2 receptor ß (IL2Rß), fibroblast growth factor receptor 1 (FGFR1)), other cell surface receptors (inositol, somatostatin, angiopoeitin), ribonucleoprotein, and enzymes (tyrosine kinases, phospholipase) on day 56. There was decreased IgG reactivity to transforming growth factor-beta type 1 receptor (TGFßR1) and, in agreement with the peptide microarray findings, immunohistochemical analysis of TB-infected lymph node samples revealed an overexpression of TGFßR in granulomatous lesions. Moreover, the vesicular monoamine transporter (VMAT2) showed increased reactivity on days 112 and 252, but not on day 56 post-vaccination. IgG to interleukin 4 receptor (IL4R) showed increased reactivity at 112 days post-vaccination, while IgG to IL2Rß and FGFR1 showed decreased reactivity on days 112 and 252 as compared to day 56 post BCG vaccination. CONCLUSIONS: BCG vaccination modifies the host's immune landscape after 56 days, but this imprint changes over time. This may influence the establishment of immunological memory in BCG-vaccinated individuals.


Assuntos
Formação de Anticorpos/imunologia , Autoanticorpos/imunologia , Vacina BCG/imunologia , Peptídeos/imunologia , Análise Serial de Proteínas/métodos , Tuberculose/imunologia , Sequência de Aminoácidos , Humanos , Imunidade Humoral , Mycobacterium bovis/imunologia , Peptídeos/química , Peptídeos/metabolismo , Tuberculose/metabolismo , Tuberculose/microbiologia , Tuberculose/prevenção & controle , Vacinação
19.
J Phys Chem B ; 109(21): 10611-9, 2005 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-16852288

RESUMO

Many solid-state reactions and phase transformations performed under isothermal conditions give rise to asymmetric, sigmoidally shaped conversion-time (x-t) profiles. The mathematical treatment of such curves, as well as their physical interpretation, is often challenging. In this work, the functional form of a Maxwell-Boltzmann (M-B) distribution is used to describe the distribution of activation energies for the reagent solids, which, when coupled with an integrated first-order rate expression, yields a novel semiempirical equation that may offer better success in the modeling of solid-state kinetics. In this approach, the Arrhenius equation is used to relate the distribution of activation energies to a corresponding distribution of rate constants for the individual molecules in the reagent solids. This distribution of molecular rate constants is then correlated to the (observable) reaction time in the derivation of the model equation. In addition to providing a versatile treatment for asymmetric, sigmoidal reaction curves, another key advantage of our equation over other models is that the start time of conversion is uniquely defined at t = 0. We demonstrate the ability of our simple, two-parameter equation to successfully model the experimental x-t data for the polymorphic transformation of a pharmaceutical compound under crystallization slurry (i.e., heterogeneous) conditions. Additionally, we use a modification of this equation to model the kinetics of a historically significant, homogeneous solid-state reaction: the thermal decomposition of AgMnO4 crystals. The potential broad applicability of our statistical (i.e., dispersive) kinetic approach makes it a potentially attractive alternative to existing models/approaches.


Assuntos
Físico-Química/métodos , Compostos de Manganês/química , Óxidos/química , Prata/química , Química/métodos , Cristalização , Temperatura Alta , Cinética , Modelos Químicos , Modelos Estatísticos , Modelos Teóricos , Análise de Regressão , Temperatura
20.
S Afr J Commun Disord ; 62(1): E1-8, 2015 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-26304217

RESUMO

BACKGROUND: Upon graduation, newly qualified speech-language therapists are expected to provide services independently. This study describes new graduates' perceptions of their preparedness to provide services across the scope of the profession and explores associations between perceptions of dysphagia theory and clinical learning curricula with preparedness for adult and paediatric dysphagia service delivery. METHODS: New graduates of six South African universities were recruited to participate in a survey by completing an electronic questionnaire exploring their perceptions of the dysphagia curricula and their preparedness to practise across the scope of the profession of speech-language therapy. RESULTS: Eighty graduates participated in the study yielding a response rate of 63.49%. Participants perceived themselves to be well prepared in some areas (e.g. child language: 100%; articulation and phonology: 97.26%), but less prepared in other areas (e.g. adult dysphagia: 50.70%; paediatric dysarthria: 46.58%; paediatric dysphagia: 38.36%) and most unprepared to provide services requiring sign language (23.61%) and African languages (20.55%). There was a significant relationship between perceptions of adequate theory and clinical learning opportunities with assessment and management of dysphagia and perceptions of preparedness to provide dysphagia services. CONCLUSION: There is a need for review of existing curricula and consideration of developing a standard speech-language therapy curriculum across universities, particularly in service provision to a multilingual population, and in both the theory and clinical learning of the assessment and management of adult and paediatric dysphagia, to better equip graduates for practice.


Assuntos
Atitude do Pessoal de Saúde , Competência Clínica , Transtornos de Deglutição/terapia , Atenção à Saúde , Transtornos da Linguagem/terapia , Distúrbios da Fala/terapia , Patologia da Fala e Linguagem/educação , Adulto , Criança , Currículo , Humanos , África do Sul , Especialização , Inquéritos e Questionários
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