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1.
Methods Mol Biol ; 2809: 1-18, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38907887

RESUMO

The major histocompatibility complex (MHC) with its highly polymorphic HLA genes represents one of the most intensely studied genomic regions in the genome. MHC proteins play a key role in antigen-specific immunity and are associated with a wide range of complex diseases. Despite decades of research and many advances in the field, the characterization and interpretation of its genetic and genomic variability remain challenging. Here an overview is provided of the MHC, the nature of its exceptional variability, and the complex evolutionary processes assumed to drive this variability. Highlighted are also recent advances in the field that promise to improve our understanding of the variability in the MHC and in antigen-specific immunity more generally.


Assuntos
Evolução Molecular , Variação Genética , Antígenos HLA , Complexo Principal de Histocompatibilidade , Humanos , Antígenos HLA/genética , Complexo Principal de Histocompatibilidade/genética , Animais
3.
Artigo em Inglês | MEDLINE | ID: mdl-38626354

RESUMO

RATIONALE: Immune checkpoint inhibitor-related pneumonitis is a serious autoimmune event affecting up to 20% of patients with non-small cell lung cancer, yet the factors underpinning its development in some patients and not others are poorly understood. OBJECTIVES: To investigate the role of autoantibodies and autoreactive T cells against surfactant-related proteins in the development of pneumonitis. METHODS: The study cohort consisted of non-small cell lung cancer patients who gave blood samples before and during immune checkpoint inhibitor treatment. Serum was used for proteomics analyses and to detect autoantibodies present during pneumonitis. T cell stimulation assays and single-cell RNA sequencing were performed to investigate the specificity and functionality of peripheral autoreactive T cells. The findings were confirmed in a validation cohort comprising patients with non-small cell lung cancer and patients with melanoma. MEASUREMENTS AND MAIN RESULTS: Across both cohorts, patients who developed pneumonitis had higher pre-treatment levels of immunoglobulin G autoantibodies targeting surfactant protein-B. At the onset of pneumonitis, these patients also exhibited higher frequencies of CD4+ interferon-gamma-positive surfactant protein B-specific T cells, and expanding T cell clonotypes recognizing this protein, accompanied by a pro-inflammatory serum proteomic profile. CONCLUSIONS: Our data suggest that the co-occurrence of surfactant protein-B-specific immunoglobulin G autoantibodies and CD4+ T cells is associated with the development of pneumonitis during ICI therapy. Pre-treatment levels of these antibodies may represent a potential biomarker for elevated risk of developing pneumonitis and on-treatment levels may provide a diagnostic aid. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/).

4.
Mol Ecol Resour ; 24(4): e13935, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38332480

RESUMO

Using high-throughput sequencing for precise genotyping of multi-locus gene families, such as the major histocompatibility complex (MHC), remains challenging, due to the complexity of the data and difficulties in distinguishing genuine from erroneous variants. Several dedicated genotyping pipelines for data from high-throughput sequencing, such as next-generation sequencing (NGS), have been developed to tackle the ensuing risk of artificially inflated diversity. Here, we thoroughly assess three such multi-locus genotyping pipelines for NGS data, the DOC method, AmpliSAS and ACACIA, using MHC class IIß data sets of three-spined stickleback gDNA, cDNA and "artificial" plasmid samples with known allelic diversity. We show that genotyping of gDNA and plasmid samples at optimal pipeline parameters was highly accurate and reproducible across methods. However, for cDNA data, the gDNA-optimal parameter configuration yielded decreased overall genotyping precision and consistency between pipelines. Further adjustments of key clustering parameters were required tο account for higher error rates and larger variation in sequencing depth per allele, highlighting the importance of template-specific pipeline optimization for reliable genotyping of multi-locus gene families. Through accurate paired gDNA-cDNA typing and MHC-II haplotype inference, we show that MHC-II allele-specific expression levels correlate negatively with allele number across haplotypes. Lastly, sibship-assisted cDNA-typing of MHC-I revealed novel variants linked in haplotype blocks, and a higher-than-previously-reported individual MHC-I allelic diversity. In conclusion, we provide novel genotyping protocols for the three-spined stickleback MHC-I and -II genes, and evaluate the performance of popular NGS-genotyping pipelines. We also show that fine-tuned genotyping of paired gDNA-cDNA samples facilitates amplification bias-corrected MHC allele expression analysis.


Assuntos
Técnicas de Genotipagem , Sequenciamento de Nucleotídeos em Larga Escala , Genótipo , Alelos , Técnicas de Genotipagem/métodos , DNA Complementar , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Expressão Gênica , Haplótipos
5.
Science ; 383(6685): eadi3808, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38386728

RESUMO

Cancer risk is influenced by inherited mutations, DNA replication errors, and environmental factors. However, the influence of genetic variation in immunosurveillance on cancer risk is not well understood. Leveraging population-level data from the UK Biobank and FinnGen, we show that heterozygosity at the human leukocyte antigen (HLA)-II loci is associated with reduced lung cancer risk in smokers. Fine-mapping implicated amino acid heterozygosity in the HLA-II peptide binding groove in reduced lung cancer risk, and single-cell analyses showed that smoking drives enrichment of proinflammatory lung macrophages and HLA-II+ epithelial cells. In lung cancer, widespread loss of HLA-II heterozygosity (LOH) favored loss of alleles with larger neopeptide repertoires. Thus, our findings nominate genetic variation in immunosurveillance as a critical risk factor for lung cancer.


Assuntos
Predisposição Genética para Doença , Antígenos de Histocompatibilidade Classe II , Vigilância Imunológica , Perda de Heterozigosidade , Neoplasias Pulmonares , Humanos , Antígenos de Histocompatibilidade Classe II/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Macrófagos Alveolares/imunologia , Fatores de Risco , Fumar/imunologia , Vigilância Imunológica/genética , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Mapeamento Cromossômico , Polimorfismo de Nucleotídeo Único
6.
JACC Cardiovasc Interv ; 17(1): 1-13, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37902151

RESUMO

BACKGROUND: Treatment of patients with recurrence of in-stent restenosis (ISR) remains particularly challenging, with data and guideline recommendations for repeat percutaneous coronary intervention being scant. OBJECTIVES: The aim of this study was to investigate the long-term incidence of recurrent revascularization events after percutaneous treatment of drug-eluting stent (DES) ISR. METHODS: In this post hoc analysis, 402 patients (500 lesions) assigned to plain balloon (PB), drug-coated balloon (DCB), or DES treatment in the randomized ISAR-DESIRE 3 (Efficacy Study of Paclitaxel-Eluting Balloon, -Stent vs. Plain Angioplasty for Drug-Eluting Stent Restenosis) trial were followed up over a median of 10.3 years. The primary endpoint was total repeat target lesion revascularization (R-TLR) including all, first and recurrent, events. RESULTS: At the end of follow-up, first R-TLR was required in 204 lesions, 82 in the PB group, 70 in the DCB group, and 52 in the DES group. The total number of R-TLRs was 373: 162 in the PB group, 124 in the DCB group, and 87 in the DES group. During the first year of follow-up, the risk for total R-TLR was reduced by DCB (HR: 0.36; 95% CI: 0.24-0.54) and DES (HR: 0.23; 95% CI: 0.14-0.38) treatment compared with PB treatment. After 1 year, the risk for total R-TLR was nonsignificantly reduced by DCB treatment (HR: 0.77; 95% CI: 0.51-1.16) and significantly reduced by DES treatment (HR: 0.61; 95% CI: 0.39-0.95) compared with PB treatment. Risk in the DCB and DES groups was similar during (HR: 1.54; 95% CI: 0.89-2.69) and after (HR: 1.26; 95% CI: 0.82-1.92) 1 year. CONCLUSIONS: The total number of R-TLRs over 10 years after treatment of patients with DES ISR was high. DCBs and particularly DES were able to reduce the need for both first and recurrent revascularization compared with PB treatment.


Assuntos
Reestenose Coronária , Stents Farmacológicos , Humanos , Angioplastia Coronária com Balão , Materiais Revestidos Biocompatíveis , Angiografia Coronária , Reestenose Coronária/diagnóstico por imagem , Reestenose Coronária/etiologia , Reestenose Coronária/terapia , Stents Farmacológicos/efeitos adversos , Paclitaxel , Intervenção Coronária Percutânea , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Mol Microbiol ; 121(3): 529-542, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38131156

RESUMO

An essential process in transmission of the malaria parasite to the Anopheles vector is the conversion of mature gametocytes into gametes within the mosquito gut, where they egress from the red blood cell (RBC). During egress, male gametocytes undergo exflagellation, leading to the formation of eight haploid motile microgametes, while female gametes retain their spherical shape. Gametocyte egress depends on sequential disruption of the parasitophorous vacuole membrane and the host cell membrane. In other life cycle stages of the malaria parasite, phospholipases have been implicated in membrane disruption processes during egress, however their importance for gametocyte egress is relatively unknown. Here, we performed comprehensive functional analyses of six putative phospholipases for their role during development and egress of Plasmodium falciparum gametocytes. We localize two of them, the prodrug activation and resistance esterase (PF3D7_0709700) and the lysophospholipase 1 (PF3D7_1476700), to the parasite plasma membrane. Subsequently, we show that disruption of most of the studied phospholipase genes does neither affect gametocyte development nor egress. The exception is the putative patatin-like phospholipase 3 (PF3D7_0924000), whose gene deletion leads to a delay in male gametocyte exflagellation, indicating an important, albeit not essential, role of this enzyme in male gametogenesis.


Assuntos
Malária , Plasmodium falciparum , Animais , Masculino , Feminino , Fosfolipases/genética , Mosquitos Vetores , Eritrócitos/parasitologia
8.
Molecules ; 28(18)2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37764265

RESUMO

Desirable advancements in the field of explosive materials include the development of novel melt-castable compounds with melting points ranging from 80 to 110 °C. This is particularly important due to the limited performance and high toxicity associated with TNT (trinitrotoluene). In this study, a series of innovative melt-castable explosives featuring nitratoalkyl and azidoalkyl functionalities attached to the 3-nitro-, 4-nitro-, 3,4-dinitropyrazole, or 3-azido-4-nitropyrazole scaffold are introduced. These compounds were synthesized using straightforward methods and thoroughly characterized using various analytical techniques, including single-crystal X-ray diffraction, IR spectroscopy, multinuclear nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry, elemental analysis, and DTA. Furthermore, the energetic properties such as (theoretical) performance data, sensitivities, and compatibilities of the compounds were evaluated and compared among the different structures.

10.
Front Cell Infect Microbiol ; 13: 1163993, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37645380

RESUMO

Background: The epidemiology of Mycobacterium tuberculosis complex (MTBC) lineage 5 (L5) infections in Ghana revealed a significantly increased prevalence in Ewes compared to other self-reported ethnic groups. In that context, we sought to investigate the early phase of tuberculosis (TB) infection using ex vivo infection of macrophages derived from the blood of Ewe and Akan ethnic group volunteers with MTBC L4 and L5 strains. Methods: The study participants consisted of 16 controls, among which self-reported Akan and Ewe ethnicity was equally represented, as well as 20 cured TB cases consisting of 11 Akans and 9 Ewes. Peripheral blood mononuclear cells were isolated from both healthy controls and cured TB cases. CD14+ monocytes were isolated and differentiated into monocyte-derived macrophages (MDMs) before infection with L4 or L5 endemic strains. The bacterial load was assessed after 2 hours (uptake) as well as 3 and 7 days post-infection. Results: We observed a higher capacity of MDMs from Ewes to phagocytose L4 strains (p < 0.001), translating into a higher bacillary load on day 7 (p < 0.001) compared to L5, despite the higher replication rate of L5 in Ewe MDMs (fold change: 1.4 vs. 1.2, p = 0.03) among the controls. On the contrary, within macrophages from Akans, we observed a significantly higher phagocytic uptake of L5 (p < 0.001) compared to L4, also translating into a higher load on day 7 (p = 0.04). However, the replication rate of L4 in Akan MDMs was higher than that of L5 (fold change: L4 = 1.2, L4 = 1.1, p = 0.04). Although there was no significant difference in the uptake of L4 and L5 among cured TB cases, there was a higher bacterial load of both L4 (p = 0.02) and L5 (p = 0.02) on day 7 in Ewe MDMs. Conclusion: Our results suggest that host ethnicity (driven by host genetic diversity), MTBC genetic diversity, and individual TB infection history are all acting together to modulate the outcome of macrophage infections by MTBC.


Assuntos
Tuberculose Latente , Mycobacterium tuberculosis , Humanos , Animais , Feminino , Ovinos , Etnicidade , Gana/epidemiologia , Autorrelato , Leucócitos Mononucleares , Macrófagos
11.
Org Lett ; 25(32): 5974-5977, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37539977

RESUMO

A [3+2]-cycloaddition toward bishydroxymethyl-1,2,3-triazole makes the title compound available through selective nitration. The obtained sensitive 2-nitrotriazole was shown to have a high density of 1.764 g cm-3 and a detonation velocity of 8590 m s-1. It can also be classified as an oxidizer with an oxygen balance toward CO of 12%. Further representatives of this rare class of 2-nitro-1,2,3-triazoles were synthesized. One- and two-dimensional 15N NMR spectroscopy, crystal structure, and elemental analysis were performed.

12.
Mol Ecol Resour ; 23(7): 1706-1723, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37489282

RESUMO

Genome sequencing enables answering fundamental questions about the genetic basis of adaptation, population structure and epigenetic mechanisms. Yet, we usually need a suitable reference genome for mapping population-level resequencing data. In some model systems, multiple reference genomes are available, giving the challenging task of determining which reference genome best suits the data. Here, we compared the use of two different reference genomes for the three-spined stickleback (Gasterosteus aculeatus), one novel genome derived from a European gynogenetic individual and the published reference genome of a North American individual. Specifically, we investigated the impact of using a local reference versus one generated from a distinct lineage on several common population genomics analyses. Through mapping genome resequencing data of 60 sticklebacks from across Europe and North America, we demonstrate that genetic distance among samples and the reference genomes impacts downstream analyses. Using a local reference genome increased mapping efficiency and genotyping accuracy, effectively retaining more and better data. Despite comparable distributions of the metrics generated across the genome using SNP data (i.e. π, Tajima's D and FST ), window-based statistics using different references resulted in different outlier genes and enriched gene functions. A marker-based analysis of DNA methylation distributions had a comparably high overlap in outlier genes and functions, yet with distinct differences depending on the reference genome. Overall, our results highlight how using a local reference genome decreases reference bias to increase confidence in downstream analyses of the data. Such results have significant implications in all reference-genome-based population genomic analyses.


Assuntos
Metagenômica , Smegmamorpha , Animais , Genoma/genética , Mapeamento Cromossômico , Genômica/métodos , Análise de Sequência de DNA/métodos , Smegmamorpha/genética
13.
Nat Protoc ; 18(9): 2625-2641, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37495751

RESUMO

The human leukocyte antigen (HLA) locus is associated with more complex diseases than any other locus in the human genome. In many diseases, HLA explains more heritability than all other known loci combined. In silico HLA imputation methods enable rapid and accurate estimation of HLA alleles in the millions of individuals that are already genotyped on microarrays. HLA imputation has been used to define causal variation in autoimmune diseases, such as type I diabetes, and in human immunodeficiency virus infection control. However, there are few guidelines on performing HLA imputation, association testing, and fine mapping. Here, we present a comprehensive tutorial to impute HLA alleles from genotype data. We provide detailed guidance on performing standard quality control measures for input genotyping data and describe options to impute HLA alleles and amino acids either locally or using the web-based Michigan Imputation Server, which hosts a multi-ancestry HLA imputation reference panel. We also offer best practice recommendations to conduct association tests to define the alleles, amino acids, and haplotypes that affect human traits. Along with the pipeline, we provide a step-by-step online guide with scripts and available software ( https://github.com/immunogenomics/HLA_analyses_tutorial ). This tutorial will be broadly applicable to large-scale genotyping data and will contribute to defining the role of HLA in human diseases across global populations.


Assuntos
Antígenos HLA , Antígenos de Histocompatibilidade Classe I , Humanos , Alelos , Antígenos HLA/genética , Genótipo , Haplótipos , Aminoácidos/genética , Polimorfismo de Nucleotídeo Único , Estudo de Associação Genômica Ampla
14.
Am Heart J ; 264: 114-122, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37315878

RESUMO

BACKGROUND: Transcatheter aortic valve implantation (TAVI) was established as a standard treatment for high-operative risk patients with severe aortic stenosis (AS). Although coronary artery disease (CAD) often coexists with AS, clinical and angiographic evaluations of stenosis severity are unreliable in this specific setting. To provide precise risk stratification of coronary lesions, combined near-infrared spectroscopy and intravascular ultrasound (NIRS-IVUS) was developed to integrate morphological and molecular information on plaque composition. However, there is a lack of evidence on the association between NIRS-IVUS derived findings such as maximum 4mm lipid core burden index (maxLCBI4mm) and clinical outcomes in AS patients undergoing TAVI. This registry aims to assess feasibility and safety of NIRS-IVUS imaging in the setting of routine pre-TAVI coronary angiography to improve assessment of CAD severity. METHODS: The registry is designed as a non-randomized, prospective, observational, multicenter cohort registry. Patients referred for TAVI with angiographic evidence of CAD receive NIRS-IVUS imaging and are followed up to 24 months. Enrolled patients are classified as NIRS-IVUS positive and NIRS-IVUS negative, respectively, based on their maxLCBI4mm to compare their clinical outcomes. The primary endpoint of the registry is major adverse cardiovascular events over a 24-month follow-up period. CONCLUSIONS: Identification of patients likely or unlikely to benefit from revascularization prior to TAVI represents an important unmet clinical need. This registry is designed to investigate whether NIRS-IVUS-derived atherosclerotic plaque characteristics can identify patients and lesions at risk for future adverse cardiovascular events after TAVI, in order to refine interventional decision-making in this challenging patient population.


Assuntos
Doença da Artéria Coronariana , Placa Aterosclerótica , Substituição da Valva Aórtica Transcateter , Humanos , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/cirurgia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Estudos Prospectivos , Ultrassonografia de Intervenção/métodos , Angiografia Coronária , Sistema de Registros
15.
J Evol Biol ; 36(6): 847-873, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37255207

RESUMO

Driven by co-evolution with pathogens, host immunity continuously adapts to optimize defence against pathogens within a given environment. Recent advances in genetics, genomics and transcriptomics have enabled a more detailed investigation into how immunogenetic variation shapes the diversity of immune responses seen across domestic and wild animal species. However, a deeper understanding of the diverse molecular mechanisms that shape immunity within and among species is still needed to gain insight into-and generate evolutionary hypotheses on-the ultimate drivers of immunological differences. Here, we discuss current advances in our understanding of molecular evolution underpinning jawed vertebrate immunity. First, we introduce the immunome concept, a framework for characterizing genes involved in immune defence from a comparative perspective, then we outline how immune genes of interest can be identified. Second, we focus on how different selection modes are observed acting across groups of immune genes and propose hypotheses to explain these differences. We then provide an overview of the approaches used so far to study the evolutionary heterogeneity of immune genes on macro and microevolutionary scales. Finally, we discuss some of the current evidence as to how specific pathogens affect the evolution of different groups of immune genes. This review results from the collective discussion on the current key challenges in evolutionary immunology conducted at the ESEB 2021 Online Satellite Symposium: Molecular evolution of the vertebrate immune system, from the lab to natural populations.


Assuntos
Imunidade Adaptativa , Evolução Biológica , Animais , Imunidade Adaptativa/genética , Vertebrados/genética , Evolução Molecular , Imunidade Inata/genética
16.
Front Immunol ; 14: 1107266, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063883

RESUMO

The human leukocyte antigen (HLA) proteins are an indispensable component of adaptive immunity because of their role in presenting self and foreign peptides to T cells. Further, many complex diseases are associated with genetic variation in the HLA region, implying an important role for specific HLA-presented peptides in the etiology of these diseases. Identifying the specific set of peptides presented by an individual's HLA proteins in vivo, as a whole being referred to as the immunopeptidome, has therefore gathered increasing attention for different reasons. For example, identifying neoepitopes for cancer immunotherapy, vaccine development against infectious pathogens, or elucidating the role of HLA in autoimmunity. Despite the tremendous progress made during the last decade in these areas, several questions remain unanswered. In this perspective, we highlight five remaining key challenges in the analysis of peptide presentation and T cell immunogenicity and discuss potential solutions to these problems. We believe that addressing these questions would not only improve our understanding of disease etiology but will also have a direct translational impact in terms of engineering better vaccines and in developing more potent immunotherapies.


Assuntos
Antígenos HLA , Antígenos de Histocompatibilidade Classe I , Humanos , Peptídeos , Antígenos de Histocompatibilidade Classe II/metabolismo , Linfócitos T
17.
Cardiovasc Revasc Med ; 52: 30-36, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36822974

RESUMO

BACKGROUND: Early-generation "sandwich-design" polytetrafluorethylene (PTFE) covered coronary stents (CS) are associated with a high frequency of adverse events. New-generation single layer PTFE-CS offers the potential to enhanced procedural efficacy and improves clinical safety. Data from a dedicated study, concerning outcomes after treatment with single-layer PTFE-CS in patients undergoing percutaneous coronary intervention are scant. METHODS: This is a retrospective multicenter registry including 30 patients undergoing implantation of 39 single-layer PTFE-CS (BeGraft-coronary Stent Graft System, Bentley InnoMed GmbH, Hechingen, Germany) in native coronary arteries or saphenous bypass grafts, in 3 centers in Europe, between May 2013 and May 2019. Endpoints of interest were procedural success (placement of covered stent), binary-angiographic restenosis (BAR), percent diameter stenosis (% DS) and late-lumen loss at 6-8 months follow-up angiography, rates of target lesion revascularization (TLR), myocardial infarction (MI), stent thrombosis (ST) and mortality at 12 months. RESULTS: 28 patients underwent implantation of 37 CS due to coronary artery perforation 2 patients due to coronary artery aneurysm. Technical success was achieved in all patients (100 %). More than one stent was implanted in 7 patients (25 %) all in the perforation group. Follow-up angiography was available in 23 patients (77 %) showing favorable results: BAR = 21.8 %, %DS = 30.3 ± 27.5; LLL = 0.16 ± 0.81 mm. At 12 months all patients were alive, rates of TLR were low (3 patients, 10.0 %), there was one case of late stent thrombosis (3.3 %) and one MI (3.3 %). CONCLUSIONS: In this dedicated study, implantation of a new single layer PTFE-CS for the treatment of native coronary arteries or saphenous vein grafts after perforation or due to aneurysm showed high technical success rates and favorable angiographic and clinical efficacy. Clinical safety outcomes are encouraging, but larger prospective studies are needed to determine long-term safety of this device.


Assuntos
Doença da Artéria Coronariana , Reestenose Coronária , Infarto do Miocárdio , Trombose , Humanos , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Stents/efeitos adversos , Infarto do Miocárdio/etiologia , Resultado do Tratamento , Trombose/etiologia , Politetrafluoretileno , Reestenose Coronária/diagnóstico por imagem , Reestenose Coronária/etiologia , Reestenose Coronária/terapia , Desenho de Prótese
18.
mBio ; 14(1): e0331822, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36625655

RESUMO

Mature gametocytes of Plasmodium falciparum display a banana (falciform) shape conferred by a complex array of subpellicular microtubules (SPMT) associated with the inner membrane complex (IMC). Microtubule-associated proteins (MAPs) define MT populations and modulate interaction with pellicular components. Several MAPs have been identified in Toxoplasma gondii, and homologues can be found in the genomes of Plasmodium species, but the function of these proteins for asexual and sexual development of malaria parasites is still unknown. Here, we identified a novel subpellicular MAP, termed SPM3, that is conserved within the genus Plasmodium, especially within the subgenus Laverania, but absent in other Apicomplexa. Conditional knockdown and targeted gene disruption of Pfspm3 in Plasmodium falciparum cause severe morphological defects during gametocytogenesis, leading to round, nonfalciform gametocytes with an aberrant SPMT pattern. In contrast, Pbspm3 knockout in Plasmodium berghei, a species with round gametocytes, caused no defect in gametocytogenesis, but sporozoites displayed an aberrant motility and a dramatic defect in invasion of salivary glands, leading to a decreased efficiency in transmission. Electron microscopy revealed a dissociation of the SPMT from the IMC in Pbspm3 knockout parasites, suggesting a function of SPM3 in anchoring MTs to the IMC. Overall, our results highlight SPM3 as a pellicular component with essential functions for malaria parasite transmission. IMPORTANCE A key structural feature driving the transition between different life cycle stages of the malaria parasite is the unique three-membrane pellicle, consisting of the parasite plasma membrane (PPM) and a double membrane structure underlying the PPM termed the inner membrane complex (IMC). Additionally, there are numerous linearly arranged intramembranous particles (IMPs) linked to the IMC, which likely link the IMC to the subpellicular microtubule cytoskeleton. Here, we identified, localized, and characterized a novel subpellicular microtubule-associated protein unique to the genus Plasmodium. The knockout of this protein in the human-pathogenic species P. falciparum resulted in malformed gametocytes and aberrant microtubules. We confirmed the microtubule association in the P. berghei rodent malaria homologue and show that its knockout results in a perturbed microtubule architecture, aberrant sporozoite motility, and decreased transmission efficiency.


Assuntos
Malária , Parasitos , Animais , Humanos , Parasitos/metabolismo , Proteínas Associadas aos Microtúbulos , Plasmodium falciparum/metabolismo , Plasmodium berghei , Esporozoítos , Proteínas de Protozoários/metabolismo
19.
Chemistry ; 29(22): e202204013, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-36691978

RESUMO

In the search for high-performance and environmentally friendly energetic materials, the derivatization of known materials is an often-applied concept to fulfill modern-day demands. Surprisingly, the long know pentaerythritol tetranitrate (PETN) has only been derivatized to a limited extent. PETN shows a brought application in energetic materials or pharmaceutics. In this work, the PETN backbone is modified by introducing nitramine, ionic nitramine, amine, ionic amine and tetrazole functionalities. The obtained and structurally similar compounds allow good comparability and insights into functional group effects on sensitivity, thermal behavior and performance. The functionalizations result in melting points in the range of 64 to 126 °C. Some compounds are therefore potential candidates to replace toxic TNT.

20.
EuroIntervention ; 18(14): 1188-1196, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36453826

RESUMO

BACKGROUND: Long-term data concerning the efficacy of different polymer-coating strategies of new-generation drug-eluting stents (DES) in patients with coronary artery calcification (CAC) are scant. AIMS: We aimed to investigate 10-year outcomes by degree of CAC after new-generation DES implantation with different polymer-coating strategies. METHODS: We analysed individual patient and lesion characteristics of patients randomised to treatment with polymer-free sirolimus-eluting, biodegradable-polymer sirolimus-eluting and permanent-polymer zotarolimus- or everolimus-eluting stents. Endpoints of interest at 10 years were all-cause mortality, myocardial infarction (MI), target lesion revascularisation (TLR) and definite or probable stent thrombosis (ST) according to the degree of CAC (no, mild, moderate or severe) and coating strategy (polymer-free vs biodegradable-polymer vs permanent-polymer). RESULTS: A total of 4,953 patients with 6,924 lesions were included. No, mild, moderate or severe CAC was present in 24.5%, 41.8%, 25.8% and 8.0% of patients, respectively. At 10-year follow-up, overall event rates were high, with an incremental increase according to the degree of CAC (all-cause mortality: no 25.3%, mild 32.1%, moderate 41.7%, severe CAC 46.5%; adjusted [adj.] p=0.004; TLR: no 17.4%, mild 16.5%, moderate 19.8%, severe CAC 28.7%; adj. p=0.001; MI: no 4.9%, mild 5.9%, moderate 6.0%, severe CAC 10.5%; adj. p=0.02; and ST: no 1.3%, mild 1.4%, moderate 1.8%, severe CAC 3.6%; adj. p=0.57). In patients with moderate-severe CAC, event rates were comparable, regardless of the DES polymer-coating strategy. CONCLUSIONS: At 10 years after PCI with new-generation DES, there was an incremental increase in adverse events by degree of coronary calcification. These detrimental effects do not seem to be impacted by different polymer-coating strategies.


Assuntos
Calcinose , Doença da Artéria Coronariana , Stents Farmacológicos , Infarto do Miocárdio , Intervenção Coronária Percutânea , Trombose , Humanos , Stents Farmacológicos/efeitos adversos , Polímeros , Intervenção Coronária Percutânea/efeitos adversos , Resultado do Tratamento , Sirolimo/uso terapêutico , Doença da Artéria Coronariana/terapia , Infarto do Miocárdio/etiologia , Calcinose/complicações , Trombose/etiologia , Desenho de Prótese , Ensaios Clínicos Controlados Aleatórios como Assunto
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