Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.971
Filtrar
Mais filtros








Intervalo de ano de publicação
1.
Eur J Surg Oncol ; 50(12): 108568, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39241538

RESUMO

INTRODUCTION: To improve care for patients with colorectal peritoneal metastases (CRC-PM) or pseudomyxoma peritonei (PMP), the Dutch CRS-HIPEC quality registry was initiated in 2019. The aims are to describe the development and content of this registry and to give insight into the data collected during the first years. MATERIALS AND METHODS: The registry is an observational cohort in the Netherlands. All patients with CRC-PM or PMP who intend to undergo cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) from 6 hospitals are included. Clinical data and outcomes (including hospital variation) were analyzed. RESULTS: In 2019-2022, 889 patients were included in the CRS-HIPEC quality registry: 749 (84 %) with CRC-PM and 140 (16 %) with PMP. Peritoneal metastases were diagnosed synchronously in 51 % of CRC-PM patients and in 94 % of PMP patients. In patients undergoing complete CRS, the median peritoneal cancer index was 8 (IQR 4-13) for CRC-PM and 15 (IQR 6-26) for PMP. Complete cytoreduction was achieved in 639 CRC-PM patients (97 %) and 108 PMP patients (82 %). HIPEC was mainly performed with mitomycin C (CRC-PM: 94 %, PMP: 92 %). Major postoperative complications (Clavien-Dindo grade ≥3) occurred in 148 CRC-PM patients (22 %) and 30 PMP patients (23 %) with 90-day mortality rates of 2 %. In CRC-PM, differences between hospitals were observed regarding proportions of diagnostic laparoscopies/laparotomies, (neo)adjuvant treatment, ostomy formations and re-admissions. CONCLUSION: The CRS-HIPEC quality registry provides insight into the outcomes of CRS-HIPEC and enables clinical auditing and observational cohort studies aiming to improve treatment outcomes for patients with CRC-PM and PMP.

2.
Int J Mol Sci ; 25(17)2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39273322

RESUMO

IL-15 is a homeostatic cytokine for human T and NK cells. However, whether other cytokines influence the effect of IL-15 is not known. We studied the impact that IL-10, TGF-ß, IL-17A, and IFN-γ have on the IL-15-induced proliferation of human T cells and the expression of HLA class I (HLA-I) molecules. Peripheral blood lymphocytes (PBLs) were labeled with CFSE and stimulated for 12 days with IL-15 in the absence or presence of the other cytokines. The proportion of proliferating T cells and the expression of cell surface HLA-I molecules were analyzed using flow cytometry. The IL-15-induced proliferation of T cells was paralleled by an increase in the expression of HC-10-reactive HLA-I molecules, namely on T cells that underwent ≥5-6 cycles of cell division. It is noteworthy that the IL-15-induced proliferation of T cells was potentiated by IL-10 and TGF-ß but not by IL-17 or IFN-γ and was associated with a decrease in the expression of HC-10-reactive molecules. The cytokines IL-10 and TGF-ß potentiate the proliferative capacity that IL-15 has on human T cells in vitro, an effect that is associated with a reduction in the amount of HC-10 reactive HLA class I molecules induced by IL-15.


Assuntos
Proliferação de Células , Antígenos de Histocompatibilidade Classe I , Interferon gama , Interleucina-10 , Interleucina-15 , Interleucina-17 , Linfócitos T , Fator de Crescimento Transformador beta , Humanos , Proliferação de Células/efeitos dos fármacos , Interferon gama/farmacologia , Interferon gama/metabolismo , Interleucina-17/farmacologia , Interleucina-17/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Interleucina-10/metabolismo , Interleucina-15/farmacologia , Interleucina-15/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Linfócitos T/metabolismo , Linfócitos T/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/citologia , Células Cultivadas , Ativação Linfocitária/efeitos dos fármacos
3.
Biochem Cell Biol ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39293094

RESUMO

The human lysine acetyltransferases KAT3A (CREBBP) and KAT3B (EP300) are essential enzymes in gene regulation in the nucleus. Their ubiquitous expression in metazoan cell types controls cell proliferation and differentiation during development. This comprehensive review delves into the biological roles of KAT3A and KAT3B in neurodevelopment, shedding light on how alterations in their regulation or activity can potentially contribute to a spectrum of neurodegenerative diseases (e.g. Huntington's and Alzheimer's). We explore the pathophysiological implications of KAT3 function loss in these disorders, considering their conserved protein domains and biochemical functions in chromatin regulation. The discussion also underscores the crucial role of KAT3 proteins and their substrates in supporting the integration of key cell signaling pathways. Furthermore, the narrative highlights the interdependence of KAT3-mediated lysine acetylation with lysine methylation and arginine methylation. From a cellular perspective, KAT3-dependent signal integration at subnuclear domains is mediated by liquid-liquid phase separation in response to KAT3-mediated lysine acetylation. The disruption of these finely tuned regulatory processes underscores their pathological roles in neurodegeneration. This review also points to the exciting potential for future research in this field, inspiring further investigation and discovery in the area of neurodevelopment and neurodegenerative diseases.

5.
iScience ; 27(9): 110679, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39262785

RESUMO

Tyrannosauroids are a clade of theropod dinosaur taxa that varied greatly in their body size distribution. We investigated the feeding performance of six tyrannosaur genera of variable body size and skull morphology. We used 3D finite element analysis to test whether skull shape becomes more or less resistant to feeding-induced forces. Cranial and mandibular models were scaled by adult Tyrannosaurus's surface area to analyze the influence of shape on skull function. It was found that Tyrannosaurus experienced higher absolute stresses compared to small-bodied relatives. When surface area values were equalized across genera to account for the effect of size and test efficiency of skull shape, smaller individuals experience notably greater stresses than larger relatives due to the robust cranial osteology characterized in the allometry of tyrannosaurids. These results may indicate that the wide crania of tyrannosaurids convey a functional advantage that basal tyrannosauroids, juvenile tyrannosauroids, and alioramins lacked.

6.
Rev Med Suisse ; 20(884): 1498-1502, 2024 Aug 28.
Artigo em Francês | MEDLINE | ID: mdl-39219393

RESUMO

SGLT2 inhibitors (gliflozins) have proven their efficacy in reducing complications due to atherosclerotic cardiovascular disease, heart failure and chronic kidney disease both in placebo-controlled clinical trials and in real-life studies versus other glucose-lowering agents (except GLP-1 analogues) in patients with type 2 diabetes. Hence, observational studies demonstrate that they are poorly used in -clinical practice, including in patients at high cardiorenal risk. -Reasons are multiple and involve physicians, patients and health care system with restricted criteria for prescription and reimbursement in many countries. Bridging the gap between scientific proves from evidence-based medicine and clinical practice represents a major health-care issue.


Les inhibiteurs des SGLT2 (gliflozines) ont prouvé leur efficacité pour réduire le risque des complications de la maladie athéro­mateuse, de l'insuffisance cardiaque et de la maladie rénale chronique dans des essais cliniques contrôlés versus placebo et dans des études de vraie vie versus les autres antidiabétiques (sauf les analogues du GLP-1) chez des patients avec un diabète de type 2. Pourtant, les études observationnelles démontrent qu'ils sont peu utilisés en pratique clinique, y compris chez des patients à haut risque cardiorénal. Les raisons en sont multiples et impliquent le médecin prescripteur, le patient et, éventuellement, le système de soins avec des critères d'utilisation ou de remboursement restreints. Combler le fossé entre l'évidence scientifique apportée par la médecine factuelle et la pratique ­clinique représente un enjeu majeur de santé publique.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/efeitos adversos , Doenças Cardiovasculares/prevenção & controle , Insuficiência Cardíaca/tratamento farmacológico , Medicina Baseada em Evidências
8.
Rev Med Suisse ; 20(884): 1492-1497, 2024 Aug 28.
Artigo em Francês | MEDLINE | ID: mdl-39219392

RESUMO

Both glucagon-like peptide-1 receptor agonists (GLP-1RA) and sodium-glucose cotransporter 2 inhibitors (SGLT2i) improve cardiorenal -prognosis of at-risk patients with type 2 diabetes thanks to pleiotropic effects that are either common or specific. This article discusses the clinical efficacy of a combined therapy with the two medications. Data were obtained from post hoc analyses of subgroups of participants to cardiovascular outcome trials and from real-life observational retro-spective cohort studies. The reported superiority of the combination versus either monotherapy should be confirmed in an ongoing large prospective trial (PRECIDENTD). The extra-cost of such a combined therapy as well as the common underuse of each pharmacological class in daily clinical practice deserve attention.


Les agonistes des récepteurs du glucagon-like peptide-1 (ARGLP-1) et les inhibiteurs des cotransporteurs sodium-glucose 2 (iSGLT2) améliorent le pronostic cardiorénal des patients avec un diabète de type 2 à risque grâce à des effets pléiotropes à la fois communs et spécifiques. Cet article discute l'efficacité d'une combinaison des deux classes à partir d'analyses de sous-groupes de participants aux grands essais contrôlés à visée cardiovasculaire et de données observationnelles en vie réelle provenant d'études rétrospectives de cohortes. La supériorité de la combinaison rapportée par rapport à l'une ou l'autre monothérapie devra être confirmée dans un grand essai prospectif en cours (PRECIDENTD). Le surcoût d'une telle combinaison et la sous-utilisation déjà constatée en pratique clinique pour chaque classe méritent attention.


Assuntos
Diabetes Mellitus Tipo 2 , Quimioterapia Combinada , Receptor do Peptídeo Semelhante ao Glucagon 1 , Hipoglicemiantes , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Inibidores do Transportador 2 de Sódio-Glicose/administração & dosagem , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Quimioterapia Combinada/métodos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Doenças Cardiovasculares/prevenção & controle
9.
Appl Plant Sci ; 12(4): e11584, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39184198

RESUMO

Premise: Allopolyploidy-a hybridization-induced whole-genome duplication event-has been a major driver of plant diversification. The extent to which chromosomes pair with their proper homolog vs. with their homoeolog in allopolyploids varies across taxa, and methods to detect homoeologous gene flow (HGF) are needed to understand how HGF has shaped polyploid lineages. Methods: The ABBA-BABA test represents a classic method for detecting introgression between closely related species, but here we developed a modified use of the ABBA-BABA test to characterize the extent and direction of HGF in allotetraploid Coffea arabica. Results: We found that HGF is abundant in the C. arabica genome, with both subgenomes serving as donors and recipients of variation. We also found that HGF is highly maternally biased in plastid-targeted-but not mitochondrial-targeted-genes, as would be expected if plastid-nuclear incompatibilities exist between the two parent species. Discussion: Together, our analyses provide a simple framework for detecting HGF and new evidence consistent with selection favoring overwriting of paternally derived alleles by maternally derived alleles to ameliorate plastid-nuclear incompatibilities. Natural selection therefore appears to shape the direction and intensity of HGF in allopolyploid coffee, indicating that cytoplasmic inheritance has long-term consequences for polyploid lineages.

10.
Artigo em Inglês | MEDLINE | ID: mdl-39183148

RESUMO

CONTEXT: Some patients with classic congenital adrenal hyperplasia (CAH) survive without glucocorticoid treatment. Increased precursor concentrations in these patients might lead to higher free (biological active) cortisol concentrations by influencing the cortisol-protein binding. In 21-hydroxylase deficiency (21OHD), the most common CAH form, accumulated 21-deoxycortisol (21DF) may further increase glucocorticoid activity. Both mechanisms could explain the low occurrence of symptoms in some untreated classic CAH patients. OBJECTIVE: Develop and validate an LC-MS/MS method for free cortisol and free 21DF to quantify these steroids in untreated patients with classic CAH (n=29), non-classic CAH (NCCAH, n=5), other forms of adrenal insufficiency (AI, n=3), and controls (n=11) before and 60 minutes after Synacthen® administration. RESULTS: Unstimulated total cortisol concentrations of untreated classic CAH patients (median 109 nmol/L) were lower than in untreated NCCAH patients (249 nmol/L, p=0.010) and controls (202 nmol/L, p=0.016), but free cortisol concentrations were similar. Basal free 21DF concentrations were high in 21OHD patients (median 5.32 nmol/L) and undetectable in AI patients and controls (<0.19 nmol/L). After Synacthen® administration, free 21DF concentrations increased in 21OHD patients, while free cortisol concentrations did not change. CONCLUSIONS: Free cortisol concentrations in classic CAH patients were similar to those in controls and NCCAH patients, indicating comparable cortisol availability. Additionally, 21OHD patients produce high concentrations of 21DF, possibly explaining the low occurrence of symptoms in some classic 21OHD patients. Free cortisol and 21DF levels should be considered in evaluating adrenal insufficiency in patients with CAH.

11.
Sci Rep ; 14(1): 18007, 2024 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-39097627

RESUMO

Within the scope of this investigation, we carried out experiments to investigate the potential of the Vision Transformer (ViT) in the field of medical image analysis. The diagnosis of osteoporosis through inspection of X-ray radio-images is a substantial classification problem that we were able to address with the assistance of Vision Transformer models. In order to provide a basis for comparison, we conducted a parallel analysis in which we sought to solve the same problem by employing traditional convolutional neural networks (CNNs), which are well-known and commonly used techniques for the solution of image categorization issues. The findings of our research led us to conclude that ViT is capable of achieving superior outcomes compared to CNN. Furthermore, provided that methods have access to a sufficient quantity of training data, the probability increases that both methods arrive at more appropriate solutions to critical issues.


Assuntos
Redes Neurais de Computação , Osteoporose , Osteoporose/diagnóstico por imagem , Humanos , Raios X , Processamento de Imagem Assistida por Computador/métodos , Algoritmos
13.
bioRxiv ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39091732

RESUMO

Amyloid protein aggregates are pathological hallmarks of more than fifty human diseases including the most common neurodegenerative disorders. The atomic structures of amyloid fibrils have now been determined, but the process by which soluble proteins nucleate to form amyloids remains poorly characterised and difficult to study, even though this is the key step to understand to prevent the formation and spread of aggregates. Here we use massively parallel combinatorial mutagenesis, a kinetic selection assay, and machine learning to reveal the transition state of the nucleation reaction of amyloid beta, the protein that aggregates in Alzheimer's disease. By quantifying the nucleation of >140,000 proteins we infer the changes in activation energy for all 798 amino acid substitutions in amyloid beta and the energetic couplings between >600 pairs of mutations. This unprecedented dataset provides the first comprehensive view of the energy landscape and the first large-scale measurement of energetic couplings for a protein transition state. The energy landscape reveals that the amyloid beta nucleation transition state contains a short structured C-terminal hydrophobic core with a subset of interactions similar to mature fibrils. This study demonstrates the feasibility of using mutation-selection-sequencing experiments to study transition states and identifies the key molecular species that initiates amyloid beta aggregation and, potentially, Alzheimer's disease.

15.
Clin Transl Radiat Oncol ; 48: 100829, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39192878

RESUMO

Background: The effectiveness of radiotherapy for pancreatic cancer is debated. Patient-derived organoids (PDOs) already mimicked clinical radiation response in other cancer types, which could be valuable in pancreatic cancer as well. This study aimed to investigate whether PDOs can be used to model RT response in pancreatic cancer and to explore the presence of a dose-response correlation. Methods: PDOs derived from two pancreatic cancer patients (HUB-08-B2-022A and HUB-08-B2-026B) were irradiated with doses ranging from 0 to 40 Gray. Viability assessments were conducted after seven and 10 days by measuring ATP-levels. Results were normalized, defining the viability at 0 Gray as 100 % and an absolute viability of 0 as 0 %. The relative area under the curve (rAUC) was calculated (0 = total sensitivity, 1 = total resistance). Results: With a readout time of seven days, both HUB-08-B2-022A and HUB-08-B2-026B exhibited viability above 50 % at the highest dose of 12 Gy (rAUC of 0.79 and 0.69, respectively). With a readout time of 10 days, both PDOs showed a dose-response relation although HUB-08-B2-022A was more sensitive than HUB-08-B2-026B (rAUC of 0.37 and 0.51, respectively). Increasing the radiation dose to 40 Gy did not further affect viability, but the dose-response relation remained present (rAUC of 0.13 and 0.26, respectively). In the final experiment with a readout time of 10 days and a maximum dose of 14 Gy, the dose-response correlation was paramount in both PDOs (rAUC 0.28 and 0.45, respectively), with HUB-08-B2-022A being most sensitive. Conclusions: In this setup, both pancreatic cancer PDOs showed an irradiation dose-response correlation. These preliminary findings suggest that pancreatic cancer PDOs are suitable for assessing radiation response in vitro. Further experiments are needed to eventually simulate treatment responses to personalized treatment strategies.

16.
Anal Chem ; 96(33): 13588-13597, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39116295

RESUMO

The excellent versatility of 5-axis computer numerical control (CNC) micromilling has led to its application for prototyping NMR microcoils tailored to mass-limited samples (reducing development time and cost). However, vibrations during 5-axis milling can hinder the creation of complex 3D volume microcoils (i.e., solenoids and saddle coils). To address these limitations, a high-resolution NSCNC ELARA 4-axis milling machine was developed with the extra precision required for making complex 3D volume microcoils. Upon investigating the performance of resonators made with various copper-coated dielectrics, resonators with poly(methyl methacrylate) (PMMA) provided the best SNR/line shape. Thus, complex 1.7 mm microcoil designs were machined from Cu-coated PMMA. A milled 6.4 mm solenoid also provided 6.6× the total carbon signal for a 13C-labeled broccoli seed compared to a commercial inverse 5 mm NMR probe (demonstrating potential for larger coil designs). However, the manufacture of coils <1.7 mm with copper-coated PMMA rods was challenging as ∼0.5 mm of remaining PMMA was needed to retain their structural integrity. To manufacture smaller microcoils, both a solenoid and saddle coil (both with 1 mm O.D., 0.1 mm thick walls) were etched from Cu-coated glass capillaries using a UV picosecond laser that was mounted onto an NSCNC 5-axis MiRA7L. Both resonators showed excellent signal and identified a wide range of metabolites in a 13C-labeled algae extract, while the solenoid was further tested on two copepod egg sacs (∼4 µg of total sample). In summary, the flexibility to prototype complex microcoils in-house allows laboratories to tailor microcoils to specific mass-limited samples while avoiding the costs of cleanrooms.


Assuntos
Lasers , Espectroscopia de Ressonância Magnética , Polimetil Metacrilato , Espectroscopia de Ressonância Magnética/instrumentação , Polimetil Metacrilato/química , Cobre/química
17.
Phys Imaging Radiat Oncol ; 31: 100597, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39006756

RESUMO

Current online adaptive radiotherapy (oART) workflows require dedicated equipment. Our aim was to develop and implement an oART workflow for a C-arm linac which can be performed using standard clinically available tools. A workflow was successfully developed and implemented. Three patients receiving palliative radiotherapy for bladder cancer were treated, with 33 of 35 total fractions being delivered with the cone-beam computed tomography (CBCT)-guided oART workflow. Average oART fraction duration was 24 min from start of CBCT acquisition to end of beam on. This work shows how oART could be performed without dedicated equipment, broadening oART availability for application at existing treatment machines.

18.
Crit Rev Eukaryot Gene Expr ; 34(7): 35-49, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39072408

RESUMO

The epithelial to mesenchymal transition (EMT) is a multistep process involving structural and functional alterations that are required for cancer metastasis, as well as loss of epithelial markers (e.g., E-cadherin/CDH1) and gain of mesenchymal markers (e.g., N-cadherin/CDH2, vimentin/VIM). Pathological events modify cell-cell interactions, cell-matrix adhesion and extra cellular matrix integrity leading to cell migration, evasion from the primary tumor and augmented invasiveness in the metastatic niche. This transformation is modulated by multiple paracrine factors (e.g., chemokines, growth factor), as well as SLIT2-ROBO1 signaling that collectively regulate expression of RHO GTPases (e.g., RHOA) and EMT marker genes. Yet, the roles of SLIT proteins in cancer remain enigmatic. In some cancer types, SLIT2 is anti-tumorigenic, while in other cancers it contributes towards the metastatic phenotype. Here we investigated the ambivalent metastatic activity of SLIT2 by analyzing how cAMP/RHOA signal transduction modulates SLIT-ROBO controlled metastatic parameters in response to the phosphodiesterase inhibitor IBMX (3-isobutyl-1-methylxanthine) and paracrine factors (TGF-ß/TGFß1 and FGF2). Upon SLIT2 administration cell migration and proliferation increases in colon cancer cells and decreases in cervical cancer cells, while altering cell morphology and proliferation in both cancer types. These effects are reinforced by TGF-ß/TGFß1 and FGF2, but attenuated by elevation of cAMP with IBMX, depending on the cancer cell type. Our data indicate that SLIT2 represents a potential biomarker for cancer diagnosis, prognosis, and therapy.


Assuntos
Transição Epitelial-Mesenquimal , Fator 2 de Crescimento de Fibroblastos , Peptídeos e Proteínas de Sinalização Intercelular , Metástase Neoplásica , Proteínas do Tecido Nervoso , Proteínas Roundabout , Transdução de Sinais , Fator de Crescimento Transformador beta1 , Proteína rhoA de Ligação ao GTP , Humanos , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Proteína rhoA de Ligação ao GTP/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Fator de Crescimento Transformador beta1/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , AMP Cíclico/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/genética , Movimento Celular , Regulação Neoplásica da Expressão Gênica
19.
Int J Mol Sci ; 25(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39000369

RESUMO

Phaeochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumours arising from chromaffin cells. Pathogenic variants in the gene succinate dehydrogenase subunit B (SDHB) are associated with malignancy and poor prognosis. When metastases arise, limited treatment options are available. The pathomechanism of SDHB-associated PPGL remains largely unknown, and the lack of suitable models hinders therapy development. Germline heterozygous SDHB pathogenic variants predispose to developing PPGLs with a life-long penetrance of around 50%. To mimic the human disease phenotype, we characterised adult heterozygous sdhb mutant zebrafish as a potential model to study SDHB-related PPGLs. Adult sdhb mutant zebrafish did not develop an obvious tumour phenotype and were anatomically and histologically like their wild-type siblings. However, sdhb mutants showed significantly increased succinate levels, a major hallmark of SDHB-related PPGLs. While basal activity was increased during day periods in mutants, mitochondrial complex activity and catecholamine metabolite levels were not significantly different. In conclusion, we characterised an adult in vivo zebrafish model, genetically resembling human carriers. Adult heterozygous sdhb mutants mimicked their human counterparts, showing systemic elevation of succinate levels despite the absence of a tumour phenotype. This model forms a promising basis for developing a full tumour phenotype and gaining knowledge of the pathomechanism behind SDHB-related PPGLs.


Assuntos
Neoplasias das Glândulas Suprarrenais , Modelos Animais de Doenças , Paraganglioma , Feocromocitoma , Succinato Desidrogenase , Peixe-Zebra , Animais , Humanos , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/patologia , Mutação , Paraganglioma/genética , Paraganglioma/patologia , Paraganglioma/metabolismo , Fenótipo , Feocromocitoma/genética , Feocromocitoma/patologia , Feocromocitoma/metabolismo , Succinato Desidrogenase/genética , Succinato Desidrogenase/metabolismo , Peixe-Zebra/genética
20.
Phys Med Biol ; 69(17)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39053500

RESUMO

To ensure the accuracy of radiation delivery to patients in a 1.5 T MRI-linac, the implementation of quality assurance (QA) devices compatible with MR technology is essential. The OCTAVIUS 4D MR, made by PTW (Freiburg, Germany) is designed to ensure consistent and ideal alignment of its detectors with the direction of each beam segment. This study focuses on investigating the fundamental characteristics of the detector response for the OCTAVIUS Detector (OD) 1500 MR and OCTAVIUS 1600 MR when used in the MR-compatible OCTAVIUS 4D. Characteristics examined included short-term reproducibility, dose linearity, field size dependency, monitor unit (MU) rate dependency, dose-per-pulse dependency, and angular dependency. The evaluation of OD 1500 MR also involved measuring 25 clinical treatment plans across diverse target sizes and anatomical sites, including the liver/pancreas, rectum, prostate, lungs, and lymph nodes. One plan was measured with the standard setup and with a 5 cm left offset. The OD 1600 MR was not available for these measurements. The capability of the OD 1500 MR to identify potential errors was assessed by introducing a MU and positional shift within the software. The results demonstrated no significant differences in short-term reproducibility (<0.2%), dose linearity (<1%), field size dependency (<0.7%for field sizes larger than 5 cm × 5 cm), MU rate dependency (<0.8%), dose-per-pulse dependency (<0.4%) and angular dependency (standard deviation<0.5%). All tests of clinical plans were successfully completed. The OD 1500 MR demonstrated compatibility with the standard 95% pass rate when employing a global 3%/3 mm gamma criterion, and a 90% pass rate using a global 2%/2 mm gamma criterion. The detector demonstrated the capacity to measure treatment plans with a 5 cm left offset. With the standard parameters, the gamma test was sensitive to position errors but required an addition tests of mean/median dose or point dose in order to detect small dose difference.


Assuntos
Imageamento por Ressonância Magnética , Aceleradores de Partículas , Planejamento da Radioterapia Assistida por Computador , Imageamento por Ressonância Magnética/instrumentação , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Controle de Qualidade , Dosagem Radioterapêutica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA