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1.
CPT Pharmacometrics Syst Pharmacol ; 13(3): 410-423, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38164114

RESUMO

Oral drug absorption kinetics are usually established in populations with a properly functioning gastrointestinal tract. However, many diseases and therapeutics can alter gastrointestinal physiology and cause diarrhea. The extent of diarrhea-associated impact on drug pharmacokinetics has not been quantitatively described. To address this knowledge gap, we used a population pharmacokinetic modeling approach with data collected in a phase IIa study of matched human immunodeficiency virus (HIV)-infected adults with/without cryptosporidiosis and diarrhea to examine diarrhea-associated impact on oral clofazimine pharmacokinetics. A population pharmacokinetic model was developed with 428 plasma samples from 23 HIV-infected adults with/without Cryptosporidium infection using nonlinear mixed-effects modeling. Covariates describing cryptosporidiosis-associated diarrhea severity (e.g., number of diarrhea episodes, diarrhea grade) or HIV infection (e.g., viral load, CD4+ T cell count) were evaluated. A two-compartment model with lag time and first-order absorption and elimination best fit the data. Maximum diarrhea grade over the study duration was found to be associated with a more than sixfold reduction in clofazimine bioavailability. Apparent clofazimine clearance, intercompartmental clearance, central volume of distribution, and peripheral volume of distribution were 3.71 L/h, 18.2 L/h (interindividual variability [IIV] 45.0%), 473 L (IIV 3.46%), and 3434 L, respectively. The absorption rate constant was 0.625 h-1 (IIV 149%) and absorption lag time was 1.83 h. In conclusion, the maximum diarrhea grade observed for the duration of oral clofazimine administration was associated with a significant reduction in clofazimine bioavailability. Our results highlight the importance of studying disease impacts on oral therapeutic pharmacokinetics to inform dose optimization and maximize the chance of treatment success.


Assuntos
Criptosporidiose , Cryptosporidium , Infecções por HIV , Adulto , Humanos , Clofazimina/farmacocinética , Clofazimina/uso terapêutico , Diarreia/tratamento farmacológico , HIV , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Ensaios Clínicos Fase II como Assunto
2.
J Clin Invest ; 133(13)2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37219933

RESUMO

Multiple sclerosis (MS) is the most common chronic central nervous system inflammatory disease. Individual courses are highly variable, with complete remission in some patients and relentless progression in others. We generated induced pluripotent stem cells (iPSCs) to investigate possible mechanisms in benign MS (BMS), compared with progressive MS (PMS). We differentiated neurons and astrocytes that were then stressed with inflammatory cytokines typically associated with MS phenotypes. TNF-α/IL-17A treatment increased neurite damage in MS neurons from both clinical phenotypes. In contrast, TNF-α/IL-17A-reactive BMS astrocytes cultured with healthy control neurons exhibited less axonal damage compared with PMS astrocytes. Accordingly, single-cell transcriptomic BMS astrocyte analysis of cocultured neurons revealed upregulated neuronal resilience pathways; these astrocytes showed differential growth factor expression. Furthermore, supernatants from BMS astrocyte/neuronal cocultures rescued TNF-α/IL-17-induced neurite damage. This process was associated with a unique LIF and TGF-ß1 growth factor expression, as induced by TNF-α/IL-17 and JAK-STAT activation. Our findings highlight a potential therapeutic role of modulation of astrocyte phenotypes, generating a neuroprotective milieu. Such effects could prevent permanent neuronal damage.


Assuntos
Doenças do Sistema Nervoso Central , Células-Tronco Pluripotentes Induzidas , Esclerose Múltipla , Humanos , Técnicas de Cocultura , Interleucina-17/metabolismo , Esclerose Múltipla/genética , Esclerose Múltipla/metabolismo , Astrócitos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Neurônios/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Sistema Nervoso Central , Células Cultivadas
3.
Nat Genet ; 55(5): 880-890, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37142849

RESUMO

Extrachromosomal DNAs (ecDNAs) are common in cancer, but many questions about their origin, structural dynamics and impact on intratumor heterogeneity are still unresolved. Here we describe single-cell extrachromosomal circular DNA and transcriptome sequencing (scEC&T-seq), a method for parallel sequencing of circular DNAs and full-length mRNA from single cells. By applying scEC&T-seq to cancer cells, we describe intercellular differences in ecDNA content while investigating their structural heterogeneity and transcriptional impact. Oncogene-containing ecDNAs were clonally present in cancer cells and drove intercellular oncogene expression differences. In contrast, other small circular DNAs were exclusive to individual cells, indicating differences in their selection and propagation. Intercellular differences in ecDNA structure pointed to circular recombination as a mechanism of ecDNA evolution. These results demonstrate scEC&T-seq as an approach to systematically characterize both small and large circular DNA in cancer cells, which will facilitate the analysis of these DNA elements in cancer and beyond.


Assuntos
Neoplasias , Transcriptoma , Humanos , Transcriptoma/genética , DNA , Neoplasias/genética , Oncogenes , DNA Circular/genética
4.
Front Immunol ; 14: 1114368, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36860867

RESUMO

The critical balance between intended and adverse effects in allogeneic hematopoietic stem cell transplantation (alloHSCT) depends on the fate of individual donor T-cells. To this end, we tracked αßT-cell clonotypes during stem cell mobilization treatment with granulocyte-colony stimulating factor (G-CSF) in healthy donors and for six months during immune reconstitution after transfer to transplant recipients. More than 250 αßT-cell clonotypes were tracked from donor to recipient. These clonotypes consisted almost exclusively of CD8+ effector memory T cells (CD8TEM), which exhibited a different transcriptional signature with enhanced effector and cytotoxic functions compared to other CD8TEM. Importantly, these distinct and persisting clonotypes could already be delineated in the donor. We confirmed these phenotypes on the protein level and their potential for selection from the graft. Thus, we identified a transcriptional signature associated with persistence and expansion of donor T-cell clonotypes after alloHSCT that may be exploited for personalized graft manipulation strategies in future studies.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Transplante de Células-Tronco Hematopoéticas , Humanos , Mobilização de Células-Tronco Hematopoéticas , Transplante de Células-Tronco , Rastreamento de Células
5.
Unfallchirurgie (Heidelb) ; 125(12): 936-945, 2022 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-36355062

RESUMO

BACKGROUND: Primary total knee arthroplasty following complex knee joint trauma is only performed occasionally. In most cases a reconstruction is carried out. OBJECTIVE: Are there confirmed indications for primary total knee arthroplasty following trauma? Which special features should be paid attention to? MATERIAL AND METHODS: A selective literature search was carried out. The spectrum of indications and recommendations for action for primary total knee arthroplasty following trauma are presented, particularly against the background of demographic changes. RESULTS: The spectrum of indications for primary total knee arthroplasty following trauma is limited. This has so far been carried out only in centers with the appropriate equipment and expertise, also for the management of complications but despite good overall results is still carried out only rarely. There is a lack of studies with large patient collectives. CONCLUSION: Primary total knee arthroplasty following trauma is a safe procedure within the range of indications. The standard procedure for the vast majority of cases of complex knee trauma is a reconstruction.


Assuntos
Artroplastia do Joelho , Ferimentos e Lesões , Humanos , Artroplastia do Joelho/efeitos adversos , Coleta de Dados , Articulação do Joelho , Procedimentos de Cirurgia Plástica , Fíbula , Fraturas da Tíbia , Fraturas Ósseas
6.
Acta Physiol (Oxf) ; 235(4): e13848, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35656634

RESUMO

Single cell multi- 'Omics and Spatial Transcriptomics are prominent technological highlights of recent years, and both fields still witness a ceaseless firework of novel approaches for high resolution profiling of additional omics layers. As all life processes in organs and organisms are based on the functions of their fundamental building blocks, the individual cells and their interactions, these methods are of utmost worth for the study of physiology in health and disease. Recent discoveries on embryonic development, tumor immunology, the detailed cellular composition and function of complex tissues like for example the kidney or the brain, different roles of the same cell type in different organs, the oncogenic program of individual tumor entities, or the architecture of immunopathology in infected tissue are based on single cell and spatial transcriptomics experiments. In this review, we will give a broad overview of technological concepts for single cell and spatial analysis, showing both advantages and limitations, and illustrate their impact with some particularly impressive case studies.


Assuntos
Proteômica , Transcriptoma , Proteômica/métodos
7.
Elife ; 112022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35749158

RESUMO

The tongue is a unique muscular organ situated in the oral cavity where it is involved in taste sensation, mastication, and articulation. As a barrier organ, which is constantly exposed to environmental pathogens, the tongue is expected to host an immune cell network ensuring local immune defence. However, the composition and the transcriptional landscape of the tongue immune system are currently not completely defined. Here, we characterised the tissue-resident immune compartment of the murine tongue during development, health and disease, combining single-cell RNA-sequencing with in situ immunophenotyping. We identified distinct local immune cell populations and described two specific subsets of tongue-resident macrophages occupying discrete anatomical niches. Cx3cr1+ macrophages were located specifically in the highly innervated lamina propria beneath the tongue epidermis and at times in close proximity to fungiform papillae. Folr2+ macrophages were detected in deeper muscular tissue. In silico analysis indicated that the two macrophage subsets originate from a common proliferative precursor during early postnatal development and responded differently to systemic LPS in vivo. Our description of the under-investigated tongue immune system sets a starting point to facilitate research on tongue immune-physiology and pathology including cancer and taste disorders.


Assuntos
Papilas Gustativas , Língua , Animais , Macrófagos , Camundongos , Paladar/fisiologia , Língua/inervação
8.
J Infect Dis ; 225(10): 1765-1772, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-33507266

RESUMO

BACKGROUND: REGN3048 and REGN3051 are human monoclonal antibodies (mAb) targeting the spike glycoprotein on the Middle East respiratory syndrome coronavirus (MERS-CoV), which binds to the receptor dipeptidyl peptidase-4 (DPP4) and is necessary for infection of susceptible cells. METHODS: Preclinical study: REGN3048, REGN3051 and isotype immunoglobulin G (IgG) were administered to humanized DPP4 (huDPP4) mice 1 day prior to and 1 day after infection with MERS-CoV (Jordan strain). Virus titers and lung pathology were assessed. Phase 1 study: healthy adults received the combined mAb (n = 36) or placebo (n = 12) and followed for 121 days. Six dose levels were studied. Strict safety criteria were met prior to dose escalation. RESULTS: Preclinical study: REGN3048 plus REGN3051, prophylactically or therapeutically, was substantially more effective for reducing viral titer, lung inflammation, and pathology in huDPP4 mice compared with control antibodies and to each antibody monotherapy. Phase 1 study: REGN3048 plus REGN3051 was well tolerated with no dose-limiting adverse events, deaths, serious adverse events, or infusion reactions. Each mAb displayed pharmacokinetics expected of human IgG1 antibodies; it was not immunogenic. CONCLUSIONS: REGN3048 and REGN3051 in combination were well tolerated. The clinical and preclinical data support further development for the treatment or prophylaxis of MERS-CoV infection.


Assuntos
Infecções por Coronavirus , Coronavírus da Síndrome Respiratória do Oriente Médio , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , Dipeptidil Peptidase 4/metabolismo , Humanos , Imunoglobulina G , Camundongos , Glicoproteína da Espícula de Coronavírus
9.
RNA ; 26(11): 1726-1730, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32669295

RESUMO

MicroRNA expression is important for gene regulation and deregulated microRNA expression is often observed in diseases such as cancer. The processing of primary microRNA transcripts is an important regulatory step in microRNA biogenesis. Due to low expression level and association with chromatin, primary microRNAs are challenging to study in clinical samples where input material is limited. Here, we present a high-sensitivity targeted method to determine processing efficiency of several hundred primary microRNAs from total RNA that requires relatively few RNA sequencing reads. We validate the method using RNA from HeLa cells and show the applicability to clinical samples by analyzing RNA from normal liver and hepatocellular carcinoma. We identify 24 primary microRNAs with significant changes in processing efficiency from normal liver to hepatocellular carcinoma, among those the highly expressed miRNA-122 and miRNA-21, demonstrating that differential processing of primary microRNAs is occurring and could be involved in disease. With our method presented here we provide means to study pri-miRNA processing in disease from clinical samples.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Análise de Sequência de RNA/métodos , Regulação Neoplásica da Expressão Gênica , Células HeLa , Sequenciamento de Nucleotídeos em Larga Escala , Humanos
10.
Artigo em Inglês | MEDLINE | ID: mdl-30745383

RESUMO

Cysticercosis is a parasitic disease that frequently involves the human central nervous system (CNS), and current treatment options are limited. Oxfendazole, a veterinary medicine belonging to the benzimidazole family of anthelmintic drugs, has demonstrated substantial activity against the tissue stages of Taenia solium and has potential to be developed as an effective therapy for neurocysticercosis. To accelerate the transition of oxfendazole from veterinary to human use, the pharmacokinetics, safety, and tolerability of oxfendazole were evaluated in healthy volunteers in this phase 1 first-in-human (FIH) study. Seventy subjects were randomly assigned to receive a single oral dose of oxfendazole (0.5, 1, 3, 7.5, 15, 30, or 60 mg oxfendazole/kg body weight) or placebo and were followed for 14 days. Blood and urine samples were collected, and the concentrations of oxfendazole were measured using a validated ultraperformance liquid chromatography mass spectrometry method. The pharmacokinetic parameters of oxfendazole were estimated using noncompartmental analysis. Oxfendazole was rapidly absorbed with a mean plasma half-life ranging from 8.5 to 11 h. The renal excretion of oxfendazole was minimal. Oxfendazole exhibited significant nonlinear pharmacokinetics with less than dose-proportional increases in exposure after single oral doses of 0.5 mg/kg to 60 mg/kg. This nonlinearity of oxfendazole is likely due to the dose-dependent decrease in bioavailability that is caused by its low solubility. Oxfendazole was found to be well tolerated in this study at different escalating doses without any serious adverse events (AEs) or deaths. There were no significant differences in the distributions of hematology, biochemistry, or urine parameters between oxfendazole and placebo recipients. (This study has been registered at ClinicalTrials.gov under identifier NCT02234570.).


Assuntos
Benzimidazóis/farmacocinética , Administração Oral , Adolescente , Adulto , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Meia-Vida , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Cell Rep ; 23(12): 3429-3437, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29924987

RESUMO

Splicing efficiency varies among transcripts, and tight control of splicing kinetics is crucial for coordinated gene expression. N-6-methyladenosine (m6A) is the most abundant RNA modification and is involved in regulation of RNA biogenesis and function. The impact of m6A on regulation of RNA splicing kinetics is unknown. Here, we provide a time-resolved high-resolution assessment of m6A on nascent RNA transcripts and unveil its importance for the control of RNA splicing kinetics. We find that early co-transcriptional m6A deposition near splice junctions promotes fast splicing, while m6A modifications in introns are associated with long, slowly processed introns and alternative splicing events. In conclusion, we show that early m6A deposition specifies the fate of transcripts regarding splicing kinetics and alternative splicing.


Assuntos
Adenosina/análogos & derivados , Processamento Alternativo/genética , Análise de Sequência de RNA , Transcriptoma/genética , Adenosina/metabolismo , Sequência de Bases , Células HEK293 , Humanos , Íntrons/genética , Metiltransferases/genética , RNA/genética , Fatores de Processamento de RNA/metabolismo , Transcrição Gênica
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