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1.
Exp Cell Res ; 433(2): 113820, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37879549

RESUMO

The Warburg effect links growth and glycolysis in cancer. A key purpose of the Warburg effect is to generate glycolytic intermediates for anabolic reactions, such as nucleotides → RNA/DNA and amino acids → protein synthesis. The aim of this study was to investigate whether a similar 'glycolysis-for-anabolism' metabolic reprogramming also occurs in hypertrophying skeletal muscle. To interrogate this, we first induced C2C12 myotube hypertrophy with IGF-1. We then added 14C glucose to the differentiation medium and measured radioactivity in isolated protein and RNA to establish whether 14C had entered anabolism. We found that especially protein became radioactive, suggesting a glucose → glycolytic intermediates → non-essential amino acid(s) → protein series of reactions, the rate of which was increased by IGF-1. Next, to investigate the importance of glycolytic flux and non-essential amino acid synthesis for myotube hypertrophy, we exposed C2C12 and primary mouse myotubes to the glycolysis inhibitor 2-Deoxy-d-glucose (2DG). We found that inhibiting glycolysis lowered C2C12 and primary myotube size. Similarly, siRNA silencing of PHGDH, the key enzyme of the serine biosynthesis pathway, decreased C2C12 and primary myotube size; whereas retroviral PHGDH overexpression increased C2C12 myotube size. Together these results suggest that glycolysis is important for hypertrophying myotubes, which reprogram their metabolism to facilitate anabolism, similar to cancer cells.


Assuntos
Fator de Crescimento Insulin-Like I , Neoplasias , Animais , Camundongos , Fator de Crescimento Insulin-Like I/metabolismo , Fosfoglicerato Desidrogenase/genética , Fosfoglicerato Desidrogenase/metabolismo , Fosfoglicerato Desidrogenase/farmacologia , Fibras Musculares Esqueléticas/metabolismo , Neoplasias/metabolismo , RNA/metabolismo , Hipertrofia/metabolismo , Glucose/farmacologia , Aminoácidos/genética , Aminoácidos/metabolismo , Aminoácidos/farmacologia
2.
Plant Reprod ; 36(1): 97-106, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36149478

RESUMO

Meiosis is a specialized cell division during reproduction where one round of chromosomal replication is followed by genetic recombination and two rounds of segregation to generate recombined, ploidy-reduced spores. Meiosis is crucial to the generation of new allelic combinations in natural populations and artificial breeding programs. Several plant species are used in meiosis research including the cultivated tomato (Solanum lycopersicum) which is a globally important crop species. Here we outline the unique combination of attributes that make tomato a powerful model system for meiosis research. These include the well-characterized behavior of chromosomes during tomato meiosis, readily available genomics resources, capacity for genome editing, clonal propagation techniques, lack of recent polyploidy and the possibility to generate hybrids with twelve related wild species. We propose that further exploitation of genome bioinformatics, genome editing and artificial intelligence in tomato will help advance the field of plant meiosis research. Ultimately this will help address emerging themes including the evolution of meiosis, how recombination landscapes are determined, and the effect of temperature on meiosis.


Assuntos
Solanum lycopersicum , Inteligência Artificial , Melhoramento Vegetal , Plantas/genética , Meiose , Tecnologia , Genoma de Planta
3.
BMC Oral Health ; 22(1): 553, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36457084

RESUMO

BACKGROUND: Orofacial clefts are characterized by a frequent occurrence of dental anomalies. Numerous studies demonstrate the high prevalence of dental aplasia, supernumerary teeth, and hypoplastic teeth in patients with cleft lip with/without cleft palate (CL/P), yet the therapeutic consequences are rarely discussed. This study explores prevalence, localization, and association between primary and secondary dentition in a large European collective and begins to evaluate the significance of dental anomalies in the therapeutic course of patients with CL/P. METHODS: The medical reports of 1070 patients with different entities of CL/P who presented to our clinic within a 15-year investigation period were evaluated retrospectively. Dental anomalies were classified into three different diagnostic groups: dental aplasia, supernumerary teeth and hypoplastic teeth. The statistical analyses included studies of the frequency and localization of dental anomalies in different cleft entities as well as of the association between primary and secondary dentition and the therapeutic consequences. RESULTS: Uni- or bilateral cleft lip and palate (CLP) (47.5%) occurred most frequently, followed by cleft palate only (CPO) (32.9%) and cleft lip with or without alveolus (CL ± A) (19.6%). Dental anomalies were found significantly more often on the side of the cleft. Aplastic permanent teeth were mostly found in patients with CLP (54.8%), while supernumerary permanent teeth occurred primarily in patients with CL ± A (21.7%). Patients with CPO presented dental aplasia but no patient with CPO showed supernumerary teeth. The occurrence of dental aplasia in the primary dentition significantly increases the probability of aplastic teeth in the permanent dentition. Dental anomalies, in particular dental aplasia, significantly increase patients' need for subsequent orthodontic therapy and orthognathic surgery. CONCLUSION: Dental aplasia and hypoplasia are common in patients with CL/P not only in the cleft area but in the whole dentition. In the event of dental aplasia in the primary dentition, the frequency of aplastic teeth in the permanent dentition is significantly higher. Additionally, the need for therapeutic interventions, especially concerning orthognathic surgery, seems to be significantly higher in patients with CL/P who are affected by dental anomalies. Clinicians should take this into account when creating long-term treatment plans.


Assuntos
Fenda Labial , Fissura Palatina , Dente Supranumerário , Humanos , Fenda Labial/complicações , Fenda Labial/epidemiologia , Fissura Palatina/complicações , Fissura Palatina/epidemiologia , Estudos Retrospectivos , Dente Supranumerário/complicações , Dente Supranumerário/epidemiologia
4.
Mol Ther ; 30(9): 3078-3094, 2022 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-35821637

RESUMO

mRNA vaccines have recently proved to be highly effective against SARS-CoV-2. Key to their success is the lipid-based nanoparticle (LNP), which enables efficient mRNA expression and endows the vaccine with adjuvant properties that drive potent antibody responses. Effective cancer vaccines require long-lived, qualitative CD8 T cell responses instead of antibody responses. Systemic vaccination appears to be the most effective route, but necessitates adaptation of LNP composition to deliver mRNA to antigen-presenting cells. Using a design-of-experiments methodology, we tailored mRNA-LNP compositions to achieve high-magnitude tumor-specific CD8 T cell responses within a single round of optimization. Optimized LNP compositions resulted in enhanced mRNA uptake by multiple splenic immune cell populations. Type I interferon and phagocytes were found to be essential for the T cell response. Surprisingly, we also discovered a yet unidentified role of B cells in stimulating the vaccine-elicited CD8 T cell response. Optimized LNPs displayed a similar, spleen-centered biodistribution profile in non-human primates and did not trigger histopathological changes in liver and spleen, warranting their further assessment in clinical studies. Taken together, our study clarifies the relationship between nanoparticle composition and their T cell stimulatory capacity and provides novel insights into the underlying mechanisms of effective mRNA-LNP-based antitumor immunotherapy.


Assuntos
COVID-19 , Vacinas Anticâncer , Nanopartículas , Animais , Imunização/métodos , Imunoterapia , RNA Mensageiro/metabolismo , SARS-CoV-2/genética , Baço , Distribuição Tecidual , Vacinação/métodos
5.
BMC Cancer ; 22(1): 645, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35692047

RESUMO

BACKGROUND: Given the young age of patients with CNS WHO grade 2 and 3 oligodendrogliomas and the relevant risk of neurocognitive, functional, and quality-of-life impairment with the current aggressive standard of care treatment, chemoradiation with PCV, of the tumour located in the brain optimizing care is the major challenge. METHODS: NOA-18 aims at improving qualified overall survival (qOS) for adult patients with CNS WHO grade 2 and 3 oligodendrogliomas by randomizing between standard chemoradiation with up to six six-weekly cycles with PCV and six six-weekly cycles with lomustine and temozolomide (CETEG) (n = 182 patients per group accrued over 4 years) thereby delaying radiotherapy and adding the chemoradiotherapy concept at progression after initial radiation-free chemotherapy, allowing for effective salvage treatment and delaying potentially deleterious side effects. QOS represents a new concept and is defined as OS without functional and/or cognitive and/or quality of life deterioration regardless of whether tumour progression or toxicity is the main cause. The primary objective is to show superiority of an initial CETEG treatment followed by partial brain radiotherapy (RT) plus PCV (RT-PCV) at progression over partial brain radiotherapy (RT) followed by procarbazine, lomustine, and vincristine (PCV) chemotherapy (RT-PCV) and best investigators choice (BIC) at progression for sustained qOS. An event concerning a sustained qOS is then defined as a functional and/or cognitive and/or quality of life deterioration after completion of primary therapy on two consecutive study visits with an interval of 3 months, tolerating a deviation of at most 1 month. Assessments are done with a 3-monthly MRI, assessment of the NANO scale, HRQoL, and KPS, and annual cognitive testing. Secondary objectives are evaluation and comparison of the two groups regarding secondary endpoints (short-term qOS, PFS, OS, complete and partial response rate). The trial is planned to be conducted at a minimum of 18 NOA study sites in Germany. DISCUSSION: qOS represents a new concept. The present NOA trial aims at showing the superiority of CETEG plus RT-PCV over RT-PCV plus BIC as determined at the level of OS without sustained functional deterioration for all patients with oligodendroglioma diagnosed according to the most recent WHO classification. TRIAL REGISTRATION: Clinicaltrials.gov NCT05331521 . EudraCT 2018-005027-16.


Assuntos
Neoplasias Encefálicas , Oligodendroglioma , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Humanos , Lomustina/uso terapêutico , Gradação de Tumores , Oligodendroglioma/tratamento farmacológico , Oligodendroglioma/genética , Oligodendroglioma/patologia , Procarbazina/uso terapêutico , Qualidade de Vida , Resultado do Tratamento , Vincristina/uso terapêutico
6.
J Plast Reconstr Aesthet Surg ; 75(9): 3429-3435, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35610102

RESUMO

BACKGROUND: The objective of this study is to develop and validate a specific screening instrument for assessing the quality of life (QoL) of patients with orofacial clefts. The Cleft-Screen-Questionnaire (CSQ) aims at identifying the main problematic areas and is intended for the routine use in everyday clinical practice to constantly evaluate the conditions' and treatments' effects on patients' well-being. METHODS: First, a pool of 58 questions is created by collecting items from validated questionnaires previously used for assessing the QoL in cleft populations. After the removal of duplicate questions, the questionnaires are answered by 152 patients from a tertiary care center. A factor analysis followed by the calculation of Cronbach's alpha as a reliability measurement led to the final CSQ presented here. RESULTS: The applied factor analysis resulted in five factors. Items showing low factor loadings (seen as <0.5) were excluded initially. Accordingly, factor analysis led to a preliminary number of 43 items. A reliability analysis using Cronbach's alpha and corrected alpha if item deleted showed an overall moderate to high reliability (seen as: 0.6-0.9). After excluding questions with increasing alphas if item deleted, analyses yielded in a final number of 38 questions. CONCLUSION: The final 38-item CSQ is a reliable instrument for evaluating the health-related QoL of cleft patients.


Assuntos
Fenda Labial , Fissura Palatina , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Humanos , Psicometria , Qualidade de Vida , Reprodutibilidade dos Testes , Inquéritos e Questionários
7.
Sci Rep ; 11(1): 13683, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34211036

RESUMO

Resistance to drugs targeting the androgen receptor (AR) signaling axis remains an important challenge in the treatment of prostate cancer patients. Activation of alternative growth pathways is one mechanism used by cancer cells to proliferate despite treatment, conferring drug resistance. Through a kinome-centered CRISPR-Cas9 screen in CWR-R1 prostate cancer cells, we identified activated BRAF signaling as a determinant for enzalutamide resistance. Combined pharmaceutical targeting of AR and MAPK signaling resulted in strong synergistic inhibition of cell proliferation. The association between BRAF activation and enzalutamide resistance was confirmed in two metastatic prostate cancer patients harboring activating mutations in the BRAF gene, as both patients were unresponsive to enzalutamide. Our findings suggest that co-targeting of the MAPK and AR pathways may be effective in patients with an activated MAPK pathway, particularly in patients harboring oncogenic BRAF mutations. These results warrant further investigation of the response to AR inhibitors in BRAF-mutated prostate tumors in clinical settings.


Assuntos
Antineoplásicos/farmacologia , Benzamidas/farmacologia , Resistencia a Medicamentos Antineoplásicos , Nitrilas/farmacologia , Feniltioidantoína/farmacologia , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas B-raf/genética , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Ativação Enzimática , Humanos , Masculino , Mutação , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas B-raf/metabolismo
8.
Pediatr Transplant ; 25(6): e14023, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34014017

RESUMO

BACKGROUND: PNP is a malignancy-associated autoimmune mucocutaneous syndrome due to autoantibodies against plakins, desmogleins, and other components of the epidermis and basement membrane of epithelial tissues. PNP-causing malignancies comprise mainly lymphoproliferative and hematologic neoplasms. PNP is extremely rare, especially in children. METHODS: Here, we present the first case of a child who developed PNP on a PTLD after small bowel transplantation because of a severe genetic protein-losing enteropathy. RESULTS: The patient in this case report had a severe stomatitis, striate palmoplantar keratoderma, and lichenoid skin lesions. In addition, she had marked esophageal involvement. She had lung pathology due to recurrent pulmonary infections and ventilator injury. Although we found no evidence of BO, she died from severe pneumonia and respiratory failure at the age of 12 years. CONCLUSION: It is exceptional that, despite effective treatment of the PTLD, the girl survived 5 years after her diagnosis of PNP. We hypothesize that the girl survived relatively long after the PNP diagnosis due to strong T-cell suppressive treatments for her small bowel transplantation.


Assuntos
Intestino Delgado/transplante , Transtornos Linfoproliferativos/complicações , Síndromes Paraneoplásicas/diagnóstico , Pênfigo/diagnóstico , Enteropatias Perdedoras de Proteínas/cirurgia , Criança , Evolução Fatal , Feminino , Humanos , Imunossupressores/uso terapêutico , Gêmeos Monozigóticos
9.
Biochim Biophys Acta Gen Subj ; 1865(4): 129763, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33065252

RESUMO

Extracellular vesicles (EVs) are nanoparticles which are released by cells from all three domains of life: Archaea, Bacteria and Eukarya. They can mediate cell-cell communication by transferring cargoes such as proteins and nucleic acids between cells. EVs receive great interest in both academia and industry as they have the potential to be natural drug carriers or vaccine candidates. However, limitations to their clinical translation exist as efficient isolation, loading, labelling and surface-engineering methods are lacking. In this article, we investigate a 'post-insertion' approach, which is commonly used in the functionalization of liposomes in the pharmaceutical field, on two different EV types: mammalian cell-derived EVs and bacteria-derived EVs. We aimed to find an easy and flexible approach to functionalize EVs, thereby improving the labelling, isolation, and surface-engineering.


Assuntos
Bactérias/química , Membrana Externa Bacteriana/química , Vesículas Extracelulares/química , Imuno-Histoquímica/métodos , Animais , Membrana Externa Bacteriana/ultraestrutura , Western Blotting/métodos , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Eletroforese em Gel de Poliacrilamida/métodos , Vesículas Extracelulares/ultraestrutura , Citometria de Fluxo/métodos , Células HEK293 , Humanos , Camundongos , Microscopia Eletrônica de Transmissão/métodos , Propriedades de Superfície
10.
Int J Mol Sci ; 21(19)2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32992783

RESUMO

Nearly 100 years ago, Otto Warburg investigated the metabolism of growing tissues and discovered that tumors reprogram their metabolism. It is poorly understood whether and how hypertrophying muscle, another growing tissue, reprograms its metabolism too. Here, we studied pyruvate kinase muscle (PKM), which can be spliced into two isoforms (PKM1, PKM2). This is of interest, because PKM2 redirects glycolytic flux towards biosynthetic pathways, which might contribute to muscle hypertrophy too. We first investigated whether resistance exercise changes PKM isoform expression in growing human skeletal muscle and found that PKM2 abundance increases after six weeks of resistance training, whereas PKM1 decreases. Second, we determined that Pkm2 expression is higher in fast compared to slow fiber types in rat skeletal muscle. Third, by inducing hypertrophy in differentiated C2C12 cells and by selectively silencing Pkm1 and/or Pkm2 with siRNA, we found that PKM2 limits myotube growth. We conclude that PKM2 contributes to hypertrophy in C2C12 myotubes and indicates a changed metabolic environment within hypertrophying human skeletal muscle fibers. PKM2 is preferentially expressed in fast muscle fibers and may partly contribute to the increased potential for hypertrophy in fast fibers.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo , Fibras Musculares de Contração Rápida/enzimologia , Fibras Musculares de Contração Lenta/enzimologia , Treinamento Resistido , Hormônios Tireóideos/metabolismo , Adulto , Linhagem Celular , Humanos , Hipertrofia , Masculino , Fibras Musculares de Contração Rápida/patologia , Fibras Musculares de Contração Lenta/patologia , Proteínas de Ligação a Hormônio da Tireoide
11.
BMC Cancer ; 20(1): 16, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31906955

RESUMO

BACKGROUND: Improved, multimodal treatment strategies have been shown to increase cure rates in cancer patients. Those who survive cancer as a child, adolescent or young adult (CAYA), are at a higher risk for therapy-, or disease-related, late or long-term effects. The CARE for CAYA-Program has been developed to comprehensively assess any potential future problems, to offer need-based preventative interventions and thus to improve long-term outcomes in this particularly vulnerable population. METHODS: The trial is designed as an adaptive trial with an annual comprehensive assessment followed by needs stratified, modular interventions, currently including physical activity, nutrition and psycho-oncology, all aimed at improving the lifestyle and/or the psychosocial situation of the patients. Patients, aged 15-39 years old, with a prior cancer diagnosis, who have completed tumour therapy and are in follow-up care, and who are tumour free, will be included. At baseline (and subsequently on an annual basis) the current medical and psychosocial situation and lifestyle of the participants will be assessed using a survey compiled of various validated questionnaires (e.g. EORTC QLQ C30, NCCN distress thermometer, PHQ-4, BSA, nutrition protocol) and objective parameters (e.g. BMI, WHR, co-morbidities like hyperlipidaemia, hypertension, diabetes), followed by basic care (psychological and lifestyle consultation). Depending on their needs, CAYAs will be allocated to preventative interventions in the above-mentioned modules over a 12-month period. After 1 year, the assessment will be repeated, and further interventions may be applied as needed. During the initial trial phase, the efficacy of this approach will be compared to standard care (waiting list with intervention in the following year) in a randomized study. During this phase, 530 CAYAs will be included and 320 eligible CAYAs who are willing to participate in the interventions will be randomly allocated to an intervention. Overall, 1500 CAYAs will be included and assessed. The programme is financed by the innovation fund of the German Federal Joint Committee and will be conducted at 14 German sites. Recruitment began in January 2018. DISCUSSION: CAYAs are at high risk for long-term sequelae. Providing structured interventions to improve lifestyle and psychological situation may counteract against these risk factors. The programme serves to establish uniform regular comprehensive assessments and need-based interventions to improve long-term outcome in CAYA survivors. TRIAL REGISTRATION: Registered at the German Clinical Trial Register (ID: DRKS00012504, registration date: 19th January 2018).


Assuntos
Assistência ao Convalescente/métodos , Sobreviventes de Câncer/psicologia , Adolescente , Adulto , Assistência ao Convalescente/organização & administração , Criança , Depressão/psicologia , Depressão/terapia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/complicações , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Exercício Físico/fisiologia , Feminino , Humanos , Estilo de Vida , Masculino , Neoplasias/complicações , Neoplasias/psicologia , Avaliação Nutricional , Medicina Preventiva/métodos , Medicina Preventiva/organização & administração , Fatores de Risco , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
12.
J Ophthalmic Inflamm Infect ; 9(1): 11, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31183567

RESUMO

Vitreoretinal lymphoma as the presenting diagnosis in association with a systemic lymphoma without central nervous system involvement is exceedingly rare, and the classification of this condition is not well-established. Here, we describe a patient with intermittent blurry vision in the left eye for 2 years in the setting of a recent incidental diagnosis of diffuse large B cell lymphoma from an axillary lymph node biopsy. The diagnosis of panuveitis with an extensive exudative retinal detachment was made. The patient was treated with pars plana vitrectomy as well as systemic chemotherapy, intrathecal methotrexate, intravitreal methotrexate, and intravitreal rituximab with good post-operative outcomes.

13.
Acc Chem Res ; 52(7): 1761-1770, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31181910

RESUMO

Extracellular vesicles are nanoparticles produced by cells. They are composed of cellular membrane with associated membrane proteins that surrounds an aqueous core containing soluble molecules such as proteins and nucleic acids, like miRNA and mRNA. They are important in many physiological and pathological processes as they can transfer biological molecules from producer cells to acceptor cells. Preparation of the niche for cancer metastasis, stimulation of tissue regeneration and orchestration of the immune response are examples of the diverse processes in which extracellular vesicles have been implicated. As a result, these vesicles have formed a source of inspiration for many scientific fields. They could be used, for example, as liquid biopsies in diagnostics, as therapeutics in regenerative medicine, or as drug delivery vehicles for transport of medicines. In this Account, we focus on drug delivery applications. As we learn more and more about these vesicles, the complexity increases. What originally appeared to be a relatively uniform population of cellular vesicles is increasingly subdivided into different subsets. Cells make various distinct vesicle types whose physicochemical aspects and composition is influenced by parental cell type, cellular activation state, local microenvironment, biogenesis pathway, and intracellular cargo sorting routes. It has proven difficult to assess the effects of changes in production protocol on the characteristics of the cell-derived vesicle population. On top of that, each isolation method for vesicles necessarily enriches certain vesicle classes and subpopulations while depleting others. Also, each method is associated with a varying degree of vesicle purity and concomitant coisolation of nonvesicular material. What emerges is a staggering heterogeneity. This constitutes one of the main challenges of the field as small changes in production and isolation protocols may have large impact on the vesicle characteristics and on subsequent vesicle activity. We try to meet this challenge by careful experimental design and development of tools that enable robust readouts. By engineering the surface and cargo of extracellular vesicles through chemical and biological techniques, favorable characteristics can be enforced while unfavorable qualities can be overruled or masked. This is coupled to the precise evaluation of the interaction of extracellular vesicles with cells to determine the extracellular vesicle uptake routes and intracellular routing. Sensitive reporter assays enable reproducible analysis of functional delivery. This systematic evaluation and optimization of extracellular vesicles improves our insight into the critical determinants of extracellular vesicle activity and should improve translation into clinical application of engineered extracellular vesicles as a new class of drug delivery systems.


Assuntos
Portadores de Fármacos/química , Vesículas Extracelulares/química , Animais , Antineoplásicos/uso terapêutico , Bioengenharia , Portadores de Fármacos/metabolismo , Liberação Controlada de Fármacos , Vesículas Extracelulares/metabolismo , Humanos , Camundongos , Suínos
14.
Nanomedicine ; 20: 102014, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31152797

RESUMO

Exosomes are cell-derived extracellular vesicles of 30-150 nm in size and are involved in intercellular communication. Because of their bioactive cargo, consisting of proteins, RNA and lipids, and their natural ability to deliver these biomolecules to recipient cells, exosomes are increasingly being studied as novel drug delivery vehicles or as cell-free approaches to regenerative medicine. However, one of the major hurdles for clinical translation of therapeutic strategies based on exosomes is their low yield when produced under standard culture conditions. Exosomes are vesicles of endocytic origin and are released when multivesicular endosomes fuse with the plasma membrane. Here, we demonstrate that interfering with endolysosomal trafficking significantly increases exosome release. Furthermore, these exosomes retain their regenerative bioactivity as demonstrated by pro-survival and angiogenesis assays using both cardiomyocytes and endothelial cells. These results may be employed to increase exosome production for studying biological functions or to improve clinical translation of exosome-based therapeutics.


Assuntos
Endossomos/metabolismo , Exossomos/metabolismo , Lisossomos/metabolismo , Cloreto de Amônio/farmacologia , Transporte Biológico/efeitos dos fármacos , Biomarcadores/metabolismo , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Cloroquina/farmacologia , Endossomos/efeitos dos fármacos , Endossomos/ultraestrutura , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Exossomos/efeitos dos fármacos , Exossomos/ultraestrutura , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/ultraestrutura , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Miocárdio/citologia , Neovascularização Fisiológica/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos
15.
Cardiovasc Intervent Radiol ; 42(10): 1475-1482, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31119355

RESUMO

PURPOSE: To investigate local and systemic effects of transpulmonary chemoembolization (TPCE) with degradable starch microspheres (DSM) and doxorubicin. The long-term goal is to establish DSM-TPCE as a treatment option for pulmonary malignancies. MATERIALS AND METHODS: Nine pigs underwent TPCE of either the right or left lower lobe pulmonary artery (LLPA) and bland embolization (TPE) of the contralateral LLPA. Before the procedures, macroaggregated albumin (MAA) particles were injected into both LLPAs, to exclude systemic shunting. Pulmonary arterial pressure, heart rate and oxygenation were recorded immediately before and at 1, 3, 5 and 10 min after treatment. To investigate possible nontarget embolization, animals underwent cerebral MRI (cMRI). We killed the animals after a contrast-enhanced chest computed tomography (CT) and performed a pathologic examination at 12 h (3), 24 h (3) and 72 h (3) after treatment. RESULTS: All experiments were technically successful. Mean injected DSM dose until stasis was similar in TPCE and TPE (4.3 ± 1.4 vs. 4.0 ± 1.4 mL). Pulmonary arterial pressure increased significantly 3 min after treatment (TPE: 17 ± 5 vs. 27 ± 7 mmHg; TPCE: 22 ± 6 vs. 36 ± 8 mmHg). No significant changes in heart rate or peripheral oxygenation levels occurred. We observed no evidence of structural lung damage or permanent perfusion disruption on CT. MAA test injection and cMRI revealed no shunting or nontarget embolization. The pathologic assessment revealed nonspecific local inflammation of the lung parenchyma. CONCLUSION: In this large-animal model, TPCE and TPE appear feasible and safe. We observed a mild increase in pulmonary arterial pressure. Nontarget embolization did not occur. TPCE, as well as TPE, did not cause structural damage to the normal lung parenchyma.


Assuntos
Quimioembolização Terapêutica/métodos , Pulmão/efeitos dos fármacos , Amido/administração & dosagem , Animais , Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Pulmão/diagnóstico por imagem , Modelos Animais , Suínos , Tomografia Computadorizada por Raios X/métodos
16.
Oncotarget ; 10(22): 2224-2234, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31040913

RESUMO

BACKGROUND: Irinotecan use is limited due to severe toxicity. Preconditioning by fasting (PBF) protects against side effects of irinotecan while preserving its antitumor activity. The mechanisms underlying the effects of PBF still need to be elucidated. Here, we investigated the transcriptional responses of PBF on irinotecan in both tumor and healthy liver tissue. EXPERIMENTAL APPROACH: Male BALB/c mice were subcutaneously injected with C26 colon carcinoma cells. Twelve days after tumor inoculation, two groups were fasted for three days and two groups were allowed food ad libitum (AL). Subsequently, both groups received one dose of irinotecan. Twelve hours after administration mice were sacrificed and blood, tumor and liver tissue were harvested. Blood samples were analyzed to determine liver, kidney and bone marrow function, tissues were used for transcriptome analyses. KEY RESULTS: The AL irinotecan group showed worsened organ function and decreased leukocyte numbers. These effects were abated in PBF animals. PBF led to an altered transcriptional response in the liver of irinotecan-treated mice, including decreased cellular injury and increased stress resistance. Hepatic metabolism of irinotecan was also significantly changed due to PBF. The transcriptional response of tumor tissue observed after PBF was hardly affected compared to AL fed animals. CONCLUSIONS: Transcriptional changes after PBF to irinotecan treatment showed an improved protective stress response in healthy liver but not in tumor tissue, including changes in irinotecan metabolism. These data help to unravel the mechanisms underlying the effects of fasting on irinotecan and help to improve outcome of chemotherapeutic treatment in cancer patients.

17.
Ned Tijdschr Geneeskd ; 1622018 11 21.
Artigo em Holandês | MEDLINE | ID: mdl-30500120

RESUMO

A recent meta-analysis by Rothwell and colleagues, presented in The Lancet, of studies using aspirin as primary prevention showed that the effectiveness of the medication was weight-dependent. We discuss the results from both a pharmacological and cardiological perspective to assess the conclusions of this study. The observed result in the meta-analysis could possibly be explained by applying pharmacological principles; however, from a cardiological point of view the extent to which it has an influence on clinical practice is questionable. Notably, the included studies were conducted relatively long ago and results are, therefore, difficult to translate to a more contemporary population; furthermore, it is important to note that in current cardiology practice aspirin is not indicated as primary prevention. Nonetheless, given the complex interaction between patient-related factors and medication in the current population with multiple comorbidities, the present study provides food for thought regarding personalization of therapy.


Assuntos
Cardiologia , Neoplasias , Aspirina , Peso Corporal , Humanos , Prevenção Primária
18.
ACS Nano ; 12(10): 9815-9829, 2018 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-30256609

RESUMO

In vitro transcribed mRNA constitutes a versatile platform to encode antigens and to evoke CD8 T-cell responses. Systemic delivery of mRNA packaged into cationic liposomes (lipoplexes) has proven particularly powerful in achieving effective antitumor immunity in animal models. Yet, T-cell responses to mRNA lipoplexes critically depend on the induction of type I interferons (IFN), potent pro-inflammatory cytokines, which inflict dose-limiting toxicities. Here, we explored an advanced hybrid lipid polymer shell mRNA nanoparticle (lipopolyplex) endowed with a trimannose sugar tree as an alternative delivery vehicle for systemic mRNA vaccination. Like mRNA lipoplexes, mRNA lipopolyplexes were extremely effective in conferring antitumor T-cell immunity upon systemic administration. Conversely to mRNA lipoplexes, mRNA lipopolyplexes did not rely on type I IFN for effective T-cell immunity. This differential mode of action of mRNA lipopolyplexes enabled the incorporation of N1 methyl pseudouridine nucleoside modified mRNA to reduce inflammatory responses without hampering T-cell immunity. This feature was attributed to mRNA lipopolyplexes, as the incorporation of thus modified mRNA into lipoplexes resulted in strongly weakened T-cell immunity. Taken together, we have identified lipopolyplexes containing N1 methyl pseudouridine nucleoside modified mRNA as potent yet low-inflammatory alternatives to the mRNA lipoplexes currently explored in early phase clinical trials.


Assuntos
Inflamação/imunologia , Lipídeos/imunologia , RNA Mensageiro/imunologia , Linfócitos T/imunologia , Animais , Células Dendríticas/imunologia , Feminino , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Tamanho da Partícula , Polímeros/química , Propriedades de Superfície , Células Tumorais Cultivadas
19.
Front Immunol ; 9: 1829, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30186282

RESUMO

Human lymphoid tissues harbor, in addition to CD56bright and CD56dim natural killer (NK) cells, a third NK cell population: CD69+CXCR6+ lymphoid tissue (lt)NK cells. The function and development of ltNK cells remain poorly understood. In this study, we performed RNA sequencing on the three NK cell populations derived from bone marrow (BM) and blood. In ltNK cells, 1,353 genes were differentially expressed compared to circulating NK cells. Several molecules involved in migration were downregulated in ltNK cells: S1PR1, SELPLG and CD62L. By flow cytometry we confirmed that the expression profile of adhesion molecules (CD49e-, CD29low, CD81high, CD62L-, CD11c-) and transcription factors (Eomeshigh, Tbetlow) of ltNK cells differed from their circulating counterparts. LtNK cells were characterized by enhanced expression of inhibitory receptors TIGIT and CD96 and low expression of DNAM1 and cytolytic molecules (GZMB, GZMH, GNLY). Their proliferative capacity was reduced compared to the circulating NK cells. By performing gene set enrichment analysis, we identified DUSP6 and EGR2 as potential regulators of the ltNK cell transcriptome. Remarkably, comparison of the ltNK cell transcriptome to the published human spleen-resident memory CD8+ T (Trm) cell transcriptome revealed an overlapping gene signature. Moreover, the phenotypic profile of ltNK cells resembled that of CD8+ Trm cells in BM. Together, we provide transcriptional and phenotypic data that clearly distinguish ltNK cells from both the CD56bright and CD56dim NK cells and substantiate the view that ltNK cells are tissue-resident cells, which are functionally restrained in killing and have low proliferative activity.


Assuntos
Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Transcriptoma , Biomarcadores , Biologia Computacional/métodos , Citotoxicidade Imunológica , Perfilação da Expressão Gênica , Humanos , Memória Imunológica , Imunofenotipagem , Especificidade de Órgãos/imunologia , Fenótipo
20.
Orthopade ; 47(10): 842-848, 2018 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-30039468

RESUMO

CURRENT SITUATION: The discharge letter currently represents the gold standard of the information and transfer document in the field of inpatient orthopedic and trauma patient care. In the age of digitization, the smartphone is penetrating more and more areas of life as an omnipresent internet access medium and is thus fundamentally influencing the awareness of our society. Whereas the use of applications on smartphones is already well established today, the range of medical apps is rudimentary. The potential of apps on smartphones as an innovative digital communication medium is undeniable, but the currently available medical apps in orthopedics and trauma surgery are available to a small patient clientele only. FORECAST: Currently, the use of medical apps is not an adequate alternative to the discharge letter. However, it is only a matter of time before the innovative potential of applications is used as a communication tool in outpatient and inpatient care. It is, therefore, essential to start creating the legal, ethical and medical framework and to establish a relevant regulatory body.


Assuntos
Aplicativos Móveis , Ortopedia , Alta do Paciente , Traumatologia , Humanos , Internet
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