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1.
J Nutr ; 152(5): 1358-1369, 2022 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-35020932

RESUMEN

BACKGROUND: The wireless motility capsule (WMC) technique is a noninvasive and radiation-free method for measuring regional and whole gut transit in response to ingestion of a granola bar (SmartBar) or an eggbeater meal. The WMC has the potential to measure gastrointestinal transit in metabolic research as part of a standardized mixed meal tolerance test. OBJECTIVES: To evaluate gastrointestinal transit with the WMC and postprandial plasma/serum concentrations of metabolites and gastrointestinal hormones as well as subjective appetite following ingestion of a SmartBar compared with a standardized mixed meal. METHODS: Fourteen healthy participants [3 men, median (IQR) age 53.8 (45.8; 64.50) y, body weight 63.9 (59.9; 69.7) kg, BMI 23.1 (21.8; 23.9) kg/m2] completed a 2-d crossover study. Following ingestion of either a SmartBar (260 kcal, 7 energy percent (E%) fat, 74E% carbohydrate, and 19E% protein) or a standardized mixed meal (498 kcal, 34E% fat, 49E% carbohydrate, and 17E% protein), participants swallowed the WMC. Blood samples were drawn in the fasted state and postprandially for analyses of gastrointestinal hormones and metabolites. The primary outcome was difference in gastric emptying time between the 2 test days. Wilcoxon signed rank tests were used to test differences between test days. RESULTS: Median (IQR) gastric emptying time was 98.0 (70.0; 113.0) min longer (P = 0.001) and incremental area under the curve of triglyceride, glucose-dependent insulinotropic polypeptide, and peptide YY were 40 mmol/L × min, 45.7%, and 63.7% greater after the standardized mixed meal compared with the SmartBar (all P < 0.001). CONCLUSIONS: The WMC can be used in combination with a standardized mixed meal for evaluation of gastrointestinal transit in healthy men and women. Gastric emptying time was prolonged in response to the standardized mixed meal whereas transit times of the small bowel, colon, and whole gut did not differ between the test meals.


Asunto(s)
Hormonas Gastrointestinales , Tránsito Gastrointestinal , Carbohidratos , Estudios Cruzados , Femenino , Vaciamiento Gástrico/fisiología , Tránsito Gastrointestinal/fisiología , Humanos , Masculino , Comidas , Persona de Mediana Edad
2.
J Environ Manage ; 317: 115319, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35642810

RESUMEN

This study investigated whole-farm methane emissions from five Danish pig farms with different manure management practices and compared measured emission rates to international and national greenhouse gas inventory emission models. Methane emissions were quantified by using the tracer gas dispersion method. Farms were measured between five and eight times throughout a whole year. One of the farms housed sows and weaners (P1) and the others focused on fattening pigs (P2-P5). The farms had different manure treatment practices including biogasification (P3), acidification (P4-P5) and no manure treatment (liquid slurry) (P1-P2). Quantified methane emissions ranged from 0.2 to 20 kg/h and the highest rates were seen at the farms with fattening pigs and with no manure treatment (P2), while the lowest emissions were detected at farms with manure acidification (P4 and P5). Average methane emission factors (EFs), normalised based on livestock units, were 14 ± 6, 18 ± 9, 8 ± 7, 2 ± 1 and 1 ± 1 g/LU/h, for P1, P2, P3, P4 and P5, respectively. Emissions from fattening pig farms with biogasification (P3) and acidification (P4-P5) facilities were 55% and 91-93% lower, respectively, than from farm with no manure treatment (P2). Inventory models underestimated farm-measured methane emissions on average by 51%, across all models and farms, with the Danish model performing the worst (underestimation of 64%). A revision of model parameters related to manure emissions, such as the estimation of volatile solids excreted and methane conversion factor parameters, could improve model output, although more data needs to be collected to strengthen the conclusions. As one of the first studies assessing whole-pig farm emissions, the results showed the potential of the applied measuring method to identify mitigation strategy efficiencies and highlighted the necessity to investigate inventory model accuracy.


Asunto(s)
Gases de Efecto Invernadero , Metano , Animales , Dinamarca , Granjas , Femenino , Estiércol/análisis , Metano/análisis , Porcinos
3.
Arterioscler Thromb Vasc Biol ; 39(11): 2273-2288, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31533473

RESUMEN

OBJECTIVE: Activation of endothelial ß-catenin signaling by neural cell-derived Norrin or Wnt ligands is vital for the vascularization of the retina and brain. Mutations in members of the Norrin/ß-catenin pathway contribute to inherited blinding disorders because of defective vascular development and dysfunctional blood-retina barrier. Despite a vital role for endothelial ß-catenin signaling in central nervous system health and disease, its contribution to central nervous system angiogenesis and its interactions with downstream signaling cascades remains incompletely understood. Approach and Results: Here, using genetically modified mouse models, we show that impaired endothelial ß-catenin signaling caused hypovascularization of the postnatal retina and brain because of deficient endothelial cell proliferation and sprouting. Mosaic genetic analysis demonstrated that endothelial ß-catenin promotes but is not required for tip cell formation. In addition, pharmacological treatment revealed that angiogenesis under conditions of inhibited Notch signaling depends upon endothelial ß-catenin. Importantly, impaired endothelial ß-catenin signaling abrogated the expression of the VEGFR (vascular endothelial growth factor receptor)-2 and VEGFR3 in brain microvessels but not in the lung endothelium. CONCLUSIONS: Our study identifies molecular crosstalk between the Wnt/ß-catenin and the Notch and VEGF-A signaling pathways and strongly suggest that endothelial ß-catenin signaling supports central nervous system angiogenesis by promoting endothelial cell sprouting, tip cell formation, and VEGF-A/VEGFR2 signaling.


Asunto(s)
Encéfalo/irrigación sanguínea , Endotelio Vascular/metabolismo , Neovascularización Fisiológica , Retina/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Vía de Señalización Wnt , beta Catenina/metabolismo , Animales , Proteína Axina/metabolismo , Barrera Hematoencefálica/metabolismo , Proliferación Celular , Células Endoteliales/metabolismo , Ratones Transgénicos , Microcirculación , Receptor Cross-Talk , Receptor Notch1/genética , Receptor Notch1/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética
4.
Am J Pathol ; 188(8): 1865-1881, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29803831

RESUMEN

Brain calcification of especially the basal ganglia characterizes primary familial brain calcification (PFBC). PFBC is a rare neurodegenerative disorder with neuropsychiatric and motor symptoms, and only symptomatic treatment is available. Four PFBC-associated genes are known; approximately 40% of patients carry mutations in the gene SLC20A2, which encodes the type III sodium-dependent inorganic phosphate transporter PiT2. To investigate the role of PiT2 in PFBC development, we studied Slc20a2-knockout (KO) mice using histology, microcomputed tomography, electron microscopy, and energy-dispersive X-ray spectroscopy. Slc20a2-KO mice showed histologically detectable nodules in the brain already at 8 weeks of age, which contained organic material and were weakly calcified. In 15-week-old mice, the nodules were increased in size and number and were markedly more calcified. The major minerals in overt calcifications were Ca and P, but Fe, Zn, and Al were also generally present. Electron microscopy suggested that the calcifications initiate intracellularly, mainly in pericytes and astrocytes. As the calcification grew, they incorporated organic material. Furthermore, endogenous IgG was detected around nodules, suggesting local increased blood-brain barrier permeabilities. Nodules were found in all 8-week-old Slc20a2-KO mice, but no prenatal or marked postnatal lethality was observed. Thus, besides allowing for the study of PFBC development, the Slc20a2-KO mouse is a potential solid preclinical model for evaluation of PFBC treatments.


Asunto(s)
Encefalopatías/fisiopatología , Calcinosis/fisiopatología , Fibroblastos/patología , Trastornos del Crecimiento/fisiopatología , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo III/fisiología , Animales , Animales Recién Nacidos , Células Cultivadas , Femenino , Fibroblastos/metabolismo , Masculino , Ratones , Ratones Noqueados
5.
Neurogenetics ; 17(2): 125-30, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26660102

RESUMEN

Mutations in the SLC20A2-gene encoding the inorganic phosphate (Pi) transporter PiT2 can explain approximately 40% of the familial cases of the rare neurodegenerative disorder primary familial brain calcification (Fahr's disease). The disease characteristic, cerebrovascular-associated calcifications, is also present in Slc20a2-knockout (KO) mice. Little is known about the specific role(s) of PiT2 in the brain. Recent in vitro studies, however, suggest a role in regulation of the [Pi] in cerebrospinal fluid (CSF). We here show that Slc20a2-KO mice indeed have a high CSF [Pi] in agreement with a role of PiT2 in Pi export from the CSF. The implications in relation to disease mechanism are discussed.


Asunto(s)
Fosfatos/líquido cefalorraquídeo , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo III/genética , Animales , Calcinosis/líquido cefalorraquídeo , Calcinosis/genética , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación , Enfermedades Neurodegenerativas/líquido cefalorraquídeo , Enfermedades Neurodegenerativas/genética , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo III/metabolismo
6.
Mol Cell Biochem ; 406(1-2): 151-61, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25963666

RESUMEN

The anti-apoptotic protein kinase CK2 increasingly becomes an attractive target in cancer research with great therapeutic potential. Here, we have performed an in vitro screening of the Diversity Set III of the DTP program from the NCI/NIH, comprising 1600 compounds. We have identified 1,3-Dichloro-6-[(E)-((4-methoxyphenyl)imino)methyl] dibenzo(b,d) furan-2,7-diol (referred to as D11) to be a potent and selective inhibitor of protein kinase CK2. The D11 compound was tested against 354 eukaryotic protein kinases. By setting the threshold for inhibition to <2% remaining kinase activity, only DYRK1B, IRAK1 and PIM3 were inhibited to an extent as the tetrameric CK2 holoenzyme and its catalytic subunits α and α'. The IC50 values for the CK2α and CK2α' were on average 1-2 nM in comparison to the DYRK1B, IRAK1 and PIM3 kinases, which ranged from 18 to 49 nM. Cell permeability and efficacy of D11 were tested with cells in culture. In MIA PaCa-2 cells (human pancreatic carcinoma cell line), the phosphorylation of the CK2 biomarker CDC37 at S13 was almost completely inhibited in the presence of D11. This was observed both under normoxia and hypoxia. In the case of the human non-small cell lung carcinoma cell line, H1299, increasing amounts of D11 led to an inhibition of S380/T382/383 phosphorylation in PTEN, another biomarker for CK2 activity.


Asunto(s)
Antineoplásicos/química , Quinasa de la Caseína II/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/química , Secuencia de Aminoácidos , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Quinasa de la Caseína II/química , Quinasa de la Caseína II/metabolismo , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Datos de Secuencia Molecular , Permeabilidad , Inhibidores de Proteínas Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Bibliotecas de Moléculas Pequeñas
7.
Acta Orthop ; 84(1): 92-7, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23409845

RESUMEN

BACKGROUND AND PURPOSE: There have been numerous reports of animal models of osteomyelitis. Very few of these have been prosthesis models that imitate human conditions. We have developed a new rat model of implant-related osteomyelitis that mimics human osteomyelitis, to investigate the pathology of infection after orthopedic implant surgery. METHODS: 2 wild-type strains of Staphylococcus aureus, MN8 and UAMS-1, and their corresponding mutants that are unable to produce poly-N-acetyl glucosamine (PNAG) (ica::tet) were injected into the medullary canals of the femur and tibia at 3 different doses: 10(2), 10(3), and > 10(4) CFU/rat. We measured clinical signs, inflammatory markers, radiographic signs, histopathology, and bacteriology in the infected animals. RESULTS: An inoculum of at least 10(4) cfu of either wild-type bacterial strain resulted in histological, bacteriological, and radiographic signs of osteomyelitis with loosening of the prosthesis. An inoculum of 10(3) CFU gave signs of osteomyelitis but the prosthesis remained in situ. Bacterial inocula of 10(2) cfu gave no signs of osteolysis. INTERPRETATION: We have established a new knee prosthesis model that is suitable for reliable induction of experimental implant-associated osteomyelitis with the prosthesis in situ, using a small inoculum of S. aureus. At a dose of 10(3) CFU/rat, bacteria unable to produce PNAG (ica::tet) had only minor defects in their virulence.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/efectos adversos , Modelos Animales de Enfermedad , Osteomielitis/etiología , Infecciones Relacionadas con Prótesis/etiología , Animales , Artroplastia de Reemplazo de Rodilla/instrumentación , Artroplastia de Reemplazo de Rodilla/métodos , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/microbiología , Articulación de la Rodilla/patología , Masculino , Osteomielitis/diagnóstico por imagen , Osteomielitis/microbiología , Osteomielitis/patología , Infecciones Relacionadas con Prótesis/diagnóstico por imagen , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Relacionadas con Prótesis/patología , Radiografía , Ratas , Ratas Sprague-Dawley , Infecciones Estafilocócicas/etiología , Infecciones Estafilocócicas/microbiología
8.
Radiother Oncol ; 186: 109748, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37330055

RESUMEN

PURPOSE: To develop a novel decision-support system for radiation oncology that incorporates clinical, treatment and outcome data, as well as outcome models from a large clinical trial on magnetic resonance image-guided adaptive brachytherapy (MR-IGABT) for locally advanced cervical cancer (LACC). METHODS: A system, called EviGUIDE, was developed that combines dosimetric information from the treatment planning system, patient and treatment characteristics, and established tumor control probability (TCP), and normal tissue complication probability (NTCP) models, to predict clinical outcome of radiotherapy treatment of LACC. Six Cox Proportional Hazards models based on data from 1341 patients of the EMBRACE-I study have been integrated. One TCP model for local tumor control, and five NTCP models for OAR morbidities. RESULTS: EviGUIDE incorporates TCP-NTCP graphs to help users visualize the clinical impact of different treatment plans and provides feedback on achievable doses based on a large reference population. It enables holistic assessment of the interplay between multiple clinical endpoints and tumour and treatment variables. Retrospective analysis of 45 patients treated with MR-IGABT showed that there exists a sub-cohort of patients (20%) with increased risk factors, that could greatly benefit from the quantitative and visual feedback. CONCLUSION: A novel digital concept was developed that can enhance clinical decision- making and facilitate personalized treatment. It serves as a proof of concept for a new generation of decision support systems in radiation oncology, which incorporate outcome models and high-quality reference data, and aids the dissemination of evidence-based knowledge about optimal treatment and serve as a blueprint for other sites in radiation oncology.


Asunto(s)
Braquiterapia , Radioterapia Guiada por Imagen , Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/radioterapia , Neoplasias del Cuello Uterino/patología , Estudios Retrospectivos , Radiometría , Toma de Decisiones , Dosificación Radioterapéutica
9.
Int J Radiat Oncol Biol Phys ; 116(4): 807-824, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-36641039

RESUMEN

PURPOSE: To evaluate overall severe late morbidity (grade ≥3) in patients with locally advanced cervical cancer treated with chemo-radiation therapy and magnetic resonance image guided adaptive brachytherapy within the prospective EMBRACE-I study, and to compare the results with published literature after standard radiograph based brachytherapy (BT). METHODS AND MATERIALS: From 2008 to 2015 the EMBRACE-I study enrolled 1416 patients. Morbidity was assessed (Common Terminology Criteria for Adverse Events version 3.0) every 3 months the 1st year, every 6 months the second and third year, and yearly thereafter and 1251 patients had available follow-up on late morbidity. Morbidity events (grade 3-5) were summarized as the maximum grade during follow-up (crude incidence rates) and actuarial estimates at 3 and 5 years. To compare with the published literature on standard radiograph based BT, Common Terminology Criteria for Adverse Events scores from the EMBRACE-I study were retrospectively converted into a corresponding score in the Radiation Therapy Oncology Group and European Organization for Research and Treatment of Cancer system. RESULTS: In total, 534 severe events occurred in 270 patients; 429 events were grade 3 and 105 were grade 4 events. Actuarial estimates for grade ≥3 gastrointestinal (GI), genitourinary (GU), vaginal and fistula events at 5 years were 8.5% (95% confidence interval [CI], 6.9%-10.6%), 6.8% (95% CI, 5.4%-8.6%), 5.7% (95% CI, 4.3%-7.6%), and 3.2% (95% CI, 2.2%-4.5%), respectively. The 5-year actuarial estimate for organ-related events (GI, GU, vaginal, or fistula) was 18.4% (95% CI, 16.0%-21.2%). The 5-year actuarial estimate when aggregating all G≥3 endpoints (GI, GU, vaginal, fistulas, and non-GI/GU/vaginal) was 26.6% (95% CI, 23.8%-29.6%). Thirteen patients had a treatment-related death, 8 of which were associated with GI morbidity. CONCLUSIONS: This report assesses severe morbidity from the largest prospective study on chemo-radiation therapy and image guided adaptive brachytherapy for locally advanced cervical cancer to date. Severe late morbidity was limited per endpoint and organ category, but considerable when aggregated across organs and all endpoints. The late morbidity results in the EMBRACE-I study compare favorably with published literature on standard radiograph based BT for GI morbidity, vaginal morbidity, and fistulas.


Asunto(s)
Braquiterapia , Neoplasias del Cuello Uterino , Femenino , Humanos , Braquiterapia/efectos adversos , Braquiterapia/métodos , Neoplasias del Cuello Uterino/terapia , Neoplasias del Cuello Uterino/tratamiento farmacológico , Estudios Prospectivos , Estudios Retrospectivos , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Morbilidad , Vagina , Imagen por Resonancia Magnética/métodos , Dosificación Radioterapéutica
10.
Int J Radiat Oncol Biol Phys ; 112(3): 681-693, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-34678431

RESUMEN

PURPOSE: The purpose was to evaluate patient- and treatment-related risk factors for physician-assessed and patient-reported gastrointestinal (GI) symptoms after radio(chemo)therapy and image guided adaptive brachytherapy in locally advanced cervical cancer. METHODS AND MATERIALS: Of 1416 patients from the EMBRACE-I study, 1199 and 1002 were prospectively evaluated using physician-assessed (Common Terminology Criteria for Adverse Events [CTCAE]) and patient-reported (European Organization for Research and Treatment of Cancer [EORTC]) GI symptoms, respectively. CTCAE severe grade (grade [G] ≥3) events were pooled according to the location in the GI tract (anus/rectum, sigmoid, and colon/small bowel). CTCAE G ≥2 and EORTC "very much" and "quite a bit" plus "very much" scores (≥ "quite a bit") were analyzed for individual symptoms with Cox regression. Logistic regression was used for persistent G ≥1 and EORTC ≥ "quite a bit" symptoms, defined if present in at least half of follow-ups. RESULTS: The incidence of G ≥3 events was 2.8%, 1.8%, and 2.3% for G ≥3 anus/rectum, sigmoid, and colon/small bowel events, respectively. Among G ≥2 symptoms, diarrhea and flatulence were the most prevalent (8.5% and 9.9%, respectively). Among patient-related factors, baseline morbidity, increasing age, smoking status, and low body mass index were associated with GI symptoms to varying degrees. Among treatment-related factors, rectum D2cm3 and the International Commission on Radiation Units and Measurements recto-vaginal reference point (ICRU RV-RP) correlated with G ≥3 anus/rectum events and moderate/persistent diarrhea, proctitis, bleeding, abdominal cramps, and difficulty in bowel control. Bowel D2cm3 correlated with G ≥3 sigmoid and colon/small bowel events and moderate/persistent diarrhea and flatulence. For external beam radiation therapy (EBRT), prescription dose correlated with G ≥3 anus/rectum, diarrhea, and difficulty in bowel control. Patients with large lymph-node boost (V57Gy) were at higher risk for G ≥3 sigmoid events, moderate/persistent diarrhea, proctitis, and cramps. CONCLUSIONS: The analysis showed that both EBRT and image guided adaptive brachytherapy contribute to GI symptoms after locally advanced cervical cancer treatment. Rectum D2cm3, ICRU RV-RP , and bowel D2cm3 are risk factors for GI morbidity. The risk for various symptoms was lower with an EBRT prescription of 45 Gy than 50 Gy and increased with larger V57Gy.


Asunto(s)
Braquiterapia , Neoplasias del Cuello Uterino , Braquiterapia/métodos , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Femenino , Tracto Gastrointestinal , Humanos , Morbilidad , Dosificación Radioterapéutica , Recto , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/radioterapia
11.
Nutrients ; 13(9)2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34579074

RESUMEN

Gut-derived hormones have been suggested to play a role in bone homeostasis following food intake, although the associations are highly complex and not fully understood. In a randomized, two-day cross-over study on 14 healthy individuals, we performed postprandial time-course studies to examine the associations of the bone remodeling markers carboxyl-terminal collagen type I crosslinks (CTX) and procollagen type 1 N-terminal propeptide (P1NP) with the gut hormones glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide 1 (GLP-1), and peptide YY (PYY) using two different meal types-a standardized mixed meal (498 kcal) or a granola bar (260 kcal). Plasma concentrations of total GIP, total GLP-1, total PYY, CTX, and P1NP were measured up to 240 min after meal intake, and the incremental area under the curve (iAUC) for each marker was calculated. The iAUC of CTX and P1NP were used to assess associations with the iAUC of GIP, GLP-1, and PYY in linear mixed effect models adjusted for meal type. CTX was positively associated with GIP and GLP-1, and it was inversely associated with PYY (all p < 0.001). No associations of P1NP with GIP or GLP-1 and PYY were found. In conclusion, the postprandial responses of the gut hormones GIP, GLP-1, and PYY are associated with the bone resorption marker CTX, supporting a link between gut hormones and bone homeostasis following food intake.


Asunto(s)
Remodelación Ósea/fisiología , Resorción Ósea/sangre , Huesos/fisiología , Ingestión de Alimentos/fisiología , Hormonas Gastrointestinales/sangre , Periodo Posprandial , Área Bajo la Curva , Biomarcadores/sangre , Colágeno Tipo I/sangre , Estudios Cruzados , Femenino , Polipéptido Inhibidor Gástrico/sangre , Péptido 1 Similar al Glucagón/sangre , Voluntarios Sanos , Homeostasis , Humanos , Masculino , Comidas , Persona de Mediana Edad , Fragmentos de Péptidos/sangre , Péptido YY/sangre , Péptidos/sangre , Procolágeno/sangre , Receptores de la Hormona Gastrointestinal/sangre
12.
Int J Radiat Oncol Biol Phys ; 109(5): 1580-1587, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33227442

RESUMEN

PURPOSE: A method was recently developed for online-adaptive intensity modulated proton therapy (IMPT) in patients with cervical cancer. The advantage of this approach, relying on the use of tight margins, is challenged by the intrafraction target motion. The purpose of this study was to evaluate the dosimetric effect of intrafraction motion on the target owing to changes in bladder filling in patients with cervical cancer treated with online-adaptive IMPT. METHODS AND MATERIALS: In 10 patients selected to have large uterus motion induced by bladder filling, the intrafraction anatomic changes were simulated for several prefraction durations for online (automated) contouring and planning. For each scenario, the coverage of the primary target was evaluated with margins of 2.5 and 5 mm. RESULTS: Using a 5- mm planning target volume margin, median accumulated D98% was greater than 42.75 GyRBE1.1 (95% of the prescribed dose) in the case of a prefraction duration of 5 and 10 minutes. For a prefraction duration of 15 minutes, this parameter deteriorated to 42.6 GyRBE1.1. When margins were reduced to 2.5 mm, only a 5-minute duration resulted in median target D98% above 42.75 GyRBE1.1. In addition, smaller bladders were found to be associated with larger dose degradations compared with larger bladders. CONCLUSIONS: This study indicates that intrafraction anatomic changes can have a substantial dosimetric effect on target coverage in an online-adaptive IMPT scenario for patients subject to large uterus motion. A margin of 5 mm was sufficient to compensate for the intrafraction motion due to bladder filling for up to 10 minutes of prefraction time. However, compensation for the uncertainties that were disregarded in this study, by using margins or robust optimization, is also required. Furthermore, a large bladder volume restrains intrafraction target motion and is recommended for treating patients in this scenario. Assuming that online-adaptive IMPT remains beneficial as long as narrow margins are used (5 mm or below), this study demonstrates its feasibility with regard to intrafraction motion.


Asunto(s)
Movimientos de los Órganos , Terapia de Protones/métodos , Radioterapia de Intensidad Modulada/métodos , Vejiga Urinaria/anatomía & histología , Neoplasias del Cuello Uterino/radioterapia , Útero , Tomografía Computarizada de Haz Cónico , Fraccionamiento de la Dosis de Radiación , Estudios de Factibilidad , Femenino , Humanos , Tamaño de los Órganos , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Guiada por Imagen/métodos , Factores de Tiempo , Tomografía Computarizada por Rayos X , Vejiga Urinaria/diagnóstico por imagen , Neoplasias del Cuello Uterino/diagnóstico por imagen , Útero/diagnóstico por imagen
13.
Radiother Oncol ; 158: 312-320, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33545254

RESUMEN

PURPOSE: To identify patient- and treatment-related risk factors for fistula, bleeding, cystitis, pain and difficulty in voiding in locally advanced cervical cancer patients treated with radio(chemo)therapy and image-guided adaptive brachytherapy (IGABT). MATERIAL AND METHODS: Morbidity within the EMBRACE-I study was prospectively reported for physician-assessed (CTCAE) fistula, bleeding and cystitis and patient-reported (EORTC) pain and difficulty in voiding. Analysis of risk factors was performed in patients without bladder infiltration. Risk factors were tested with Cox regression for grade (G) ≥ 3 cystitis, for G ≥ 2 fistula, bleeding and cystitis, and for EORTC "very much" and "quite a bit" or worse. RESULTS: Of 1416 patients enrolled, 1153 and 884 patients without bladder infiltration were evaluable for the analysis of CTCAE and EORTC items, respectively. Median follow-up was 48[3-120] months. Crude incidence rates for G ≥ 2 fistula, bleeding and cystitis were 0.7%, 2.7% and 8.8%, respectively, and 16% and 14% for "quite a bit" or worse pain and difficulty in voiding, respectively. Baseline urinary morbidity and overweight/obesity were significant risk factors for most endpoints. Bladder D2cm3 correlated with G ≥ 2 fistula, bleeding and cystitis, while ICRU bladder point dose correlated with EORTC pain "quite a bit" or worse. An increase from 75 Gy to 80 Gy in bladder D2cm3 resulted in an increase from 8% to 13% for 4-year actuarial estimate of G ≥ 2 cystitis. CONCLUSION: Clinical and treatment-related risk factors for bladder fistula, bleeding and cystitis were identified within a prospective and multi-institutional setting. A dose-effect was established with bladder D2cm3, reinforcing the importance of continued optimization during individualized IGABT planning.


Asunto(s)
Braquiterapia , Cistitis , Radioterapia Guiada por Imagen , Neoplasias del Cuello Uterino , Braquiterapia/efectos adversos , Quimioradioterapia , Cistitis/epidemiología , Cistitis/etiología , Femenino , Humanos , Estudios Prospectivos , Dosificación Radioterapéutica , Factores de Riesgo , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/radioterapia
14.
Int J Radiat Oncol Biol Phys ; 109(3): 688-700, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33068689

RESUMEN

PURPOSE: To evaluate patient- and treatment-related risk factors associated with incidence and persistence of late diarrhea after radiochemotherapy and image guided adaptive brachytherapy (IGABT) in locally advanced cervical cancer. MATERIALS AND METHODS: Of 1416 patients from the EMBRACE I study, 1199 were prospectively evaluated using physician-reported (Common Terminology Criteria for Adverse Events version 3 [CTCAEv3]) assessment for diarrhea; median follow-up 48 months. Patient-reported outcome (EORTC) was available in 900 patients. Incidence of CTCAE G≥2, G≥3, and EORTC "very much" diarrhea was analyzed with Cox proportional hazards regression. Binary logistic regression was used for analysis of persistent G≥1 and EORTC "quite a bit" - "very much" (≥"quite a bit") diarrhea, defined if present in at least half of all follow-ups. RESULTS: Crude incidences of G≥2 and G≥3 diarrhea were 8.3% and 1.5%, respectively, and 8% of patients reported "very much" diarrhea. Persistent G≥1 and ≥"quite a bit" diarrhea was present in 16% and 7%, respectively. Patient-related risk factors were baseline diarrhea, smoking, and diabetes with hazard ratios of 1.4 to 7.3. Treatment-related risk factors included prescribed dose, V43 Gy, V57 Gy (lymph node boost), and para-aortic irradiation for external beam radiation therapy (EBRT). G≥2 diarrhea at 3 years increased from 9.5% to 19.9% with prescribed dose 45 Gy versus 50 Gy, 8.7% to 14.0% with V43 Gy <2500 cm3 versus >3000 cm3 and 9.4% to 19.0% with V57 Gy <165 cm3 versus ≥165 cm3. Brachytherapy-related bowel and rectum D2cm3 were also associated with diarrhea. CONCLUSION: Dose and volume effects have been established for late diarrhea after radiochemotherapy and IGABT in both CTCAE and EORTC reporting. The risk of diarrhea was lower with a pelvic EBRT prescription of 45 Gy, and higher with larger lymph node boosts volumes (ie, ≥165 cm3). The importance of EBRT volumes as determinants of late toxicity underline the need for continuous quality assurance of target contouring, dose planning, and conformity. The findings of brachytherapy dosimetric factors related to the intestines may become more important with highly conformal EBRT.


Asunto(s)
Braquiterapia/efectos adversos , Quimioradioterapia/efectos adversos , Diarrea/etiología , Radioterapia Guiada por Imagen/efectos adversos , Neoplasias del Cuello Uterino/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Braquiterapia/métodos , Quimioradioterapia/métodos , Diabetes Mellitus , Diarrea/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Intestinos/efectos de la radiación , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Dosificación Radioterapéutica , Radioterapia Guiada por Imagen/métodos , Recto/efectos de la radiación , Factores de Riesgo , Fumar/efectos adversos , Factores de Tiempo , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/patología , Adulto Joven
15.
Radiother Oncol ; 158: 300-308, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33065183

RESUMEN

PURPOSE: To identify patient- and treatment-related risk factors and dose-effects for urinary frequency and incontinence in locally advanced cervical cancer (LACC) treated with radio(chemo)therapy and image-guided adaptive brachytherapy (IGABT). MATERIAL AND METHODS: Physician-assessed (CTCAE) and patient-reported (EORTC) frequency and incontinence recorded in the EMBRACE-I study were analysed. Risk factors analysis was performed in patients without bladder infiltration and with baseline morbidity available. Cox regression was used for CTCAE grade (G) ≥ 3 and G ≥ 2 and for EORTC "very much" and "quite a bit" or worse. Logistic regression was used for late persistent morbidity defined when CTCAE G ≥ 1 or EORTC ≥ "quite a bit" were scored in at least half of follow-ups. RESULTS: Longitudinal data on 1153 and 884 patients were available for CTCAE and EORTC analysis, respectively. Median follow-up was 48[3-120] months. Crude incidence rates of G≥2 were 13% and 11% for frequency and incontinence, respectively. Baseline morbidity and overweight-obesity were risk factors for both symptoms. Elderly patients were at higher risk for incontinence. Patients receiving conformal-radiotherapy were at higher risk for frequency. ICRU bladder point (ICRU-BP) dose was a stronger predictor for incontinence than bladder D2cm3. The 5-year actuarial estimate of G ≥ 2 incontinence increased from 11% to 20% with ICRU-BP doses > 75 Gy compared to ≤ 65 Gy. Frequency showed weaker associations with dose. CONCLUSION: ICRU-BP dose, in addition to clinical parameters, is a risk factor for urinary incontinence and shows a dose-effect after radio(chemo)therapy and IGABT. ICRU-BP dose should be monitored during treatment planning alongside volumetric parameters. Frequency seems associated with larger irradiated volumes.


Asunto(s)
Braquiterapia , Incontinencia Urinaria , Neoplasias del Cuello Uterino , Anciano , Braquiterapia/efectos adversos , Femenino , Humanos , Incidencia , Dosificación Radioterapéutica , Recto , Vejiga Urinaria , Incontinencia Urinaria/epidemiología , Incontinencia Urinaria/etiología , Neoplasias del Cuello Uterino/radioterapia
16.
Int J Radiat Oncol Biol Phys ; 109(1): 161-173, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-32853710

RESUMEN

PURPOSE: This report describes the persistence of late substantial treatment-related patient-reported symptoms (LAPERS) in the multi-institutional EMBRACE study on magnetic resonance image guided adaptive brachytherapy in locally advanced cervical cancer (LACC). METHODS AND MATERIALS: Patient-reported symptoms (European Organization for Research and Treatment of Cancer [EORTC]-C30/CX24) and physician-assessed morbidity (Common Terminology Criteria for Adverse Events [CTCAE], version 3.0) were assessed at baseline and regular timepoints during follow-up. Patients with sufficient EORTC follow-up (baseline and ≥3 late follow-up visits) were analyzed. LAPERS events were defined as the presence of substantial EORTC symptoms (quite a bit/very much) for at least half of the assessments (persistence) and progression beyond baseline condition (treatment-related). For each EORTC symptom, the ratio between LAPERS rates and crude incidence rates of substantial symptoms was calculated to represent the proportion of symptomatic patients with persisting symptoms. For 9 symptoms with a corresponding EORTC/CTCAE assessment, the overlap of LAPERS and severe morbidity events (grades 3-5) was evaluated. RESULTS: Of 1047 patients with EORTC available, 741 had sufficient follow-up for the LAPERS analyses. The median follow-up was 59 months (interquartile range, 42-70 months). Across all symptoms, the proportion of patients with LAPERS events (LAPERS rates) was in median 4.6% (range, 0.0% vaginal bleeding to 20.4% tiredness). Urinary frequency, neuropathy, fatigue, insomnia, and menopausal symptoms revealed LAPERS rates of >10%. Vomiting, blood in stool, urinary pain/burning, and abnormal vaginal bleeding displayed LAPERS rates of <1%. A median of 19% of symptomatic patients (interquartile range, 8.0%-28.5%) showed persistent long-term symptoms (LAPERS events). In symptoms with a corresponding EORTC/CTCAE assessment, 12% of LAPERS events were accompanied by a severe CTCAE event. CONCLUSIONS: Within this large cohort of survivors of LACC, a subgroup of patients with persistent symptoms (LAPERS events) was identified. For symptoms with a corresponding EORTC/CTCAE assessment, the vast majority of LAPERS events occurred in patients without corresponding severe physician-assessed morbidity. These findings emphasize the importance of distinguishing between transient and persisting symptoms in the aftercare of LACC survivors.


Asunto(s)
Braquiterapia , Quimioradioterapia , Radioterapia Guiada por Imagen , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/terapia , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad , Factores de Tiempo , Resultado del Tratamiento , Neoplasias del Cuello Uterino/radioterapia , Adulto Joven
17.
Sci Rep ; 10(1): 923, 2020 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-31969592

RESUMEN

Type 2 diabetes mellitus (T2DM) affects millions of people and is linked with obesity and lipid accumulation in peripheral tissues. Increased lipid handling and lipotoxicity in insulin producing ß-cells may contribute to ß-cell dysfunction in T2DM. The vascular endothelial growth factor (VEGF)-B regulates uptake and transcytosis of long-chain fatty acids over the endothelium to tissues such as heart and skeletal muscle. Systemic inhibition of VEGF-B signaling prevents tissue lipid accumulation, improves insulin sensitivity and glucose tolerance, as well as reduces pancreatic islet triglyceride content, under T2DM conditions. To date, the role of local VEGF-B signaling in pancreatic islet physiology and in the regulation of fatty acid trans-endothelial transport in pancreatic islet is unknown. To address these questions, we have generated a mouse strain where VEGF-B is selectively depleted in ß-cells, and assessed glucose homeostasis, ß-cell function and islet lipid content under both normal and high-fat diet feeding conditions. We found that Vegfb was ubiquitously expressed throughout the pancreas, and that ß-cell Vegfb deletion resulted in increased insulin gene expression. However, glucose homeostasis and islet lipid uptake remained unaffected by ß-cell VEGF-B deficiency.


Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Ácidos Grasos/metabolismo , Expresión Génica , Glucosa/metabolismo , Homeostasis , Células Secretoras de Insulina/metabolismo , Insulina/genética , Insulina/metabolismo , Factor B de Crecimiento Endotelial Vascular/deficiencia , Factor B de Crecimiento Endotelial Vascular/fisiología , Animales , Resistencia a la Insulina/genética , Ratones Transgénicos , Transducción de Señal/fisiología , Triglicéridos/metabolismo , Regulación hacia Arriba/genética , Factor B de Crecimiento Endotelial Vascular/metabolismo
18.
Radiother Oncol ; 147: 22-29, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32240907

RESUMEN

BACKGROUND AND PURPOSE: EMBRACE-II is an international prospective study of IMRT and MRI-guided adaptive brachytherapy (IGABT) in locally advanced cervix cancer. An online radiotherapy quality assurance (RTQA) programme with minimal data transfer and supporting continuing medical education (CME) was implemented for IMRT contouring. MATERIALS AND METHODS: Participant contours for six volumes-of-interest (VOIs) on one benchmark case were scored (2 = excellent, 1 = fair, 0 = revision required) against a consensus reference contour. For contours receiving a 0 or 1 score, additional qualitative comments were provided. The Jaccard conformity index (JCI) was retrospectively calculated. User interaction with CME content (pre-accreditation questionnaire, contouring atlas, practice cases, quizzes, internal target volume (ITV-T) guide) was analysed. RESULTS: 78 clinicians submitted contours for evaluation. 41% passed at the first attempt, 44% after one revision and 6% after two or more revisions. 9% did not re-submit after failing. The lowest mean scores were for the elective nodal CTV (CTV-E) (1.01/2) and ITV-T (1.06/2). 60 different errors across the six VOIs were identified; five potentially had high impact on loco-regional control. A JCI cut-off of 0.7 would have identified 87% contours that failed expert assessment, but also excluded 54% of passing contours. 39 clinicians responded to the pre-accreditation questionnaire - 36% anticipated difficulties with the ITV-T and 13% with the CTV-E. 35% clinicians contoured on the practice cases, 17% answered a quiz, 96% used the atlas and 38% the ITV-T guide. CONCLUSION: Expert evaluation with qualitative feedback improved contouring compliance. The JCI is not a reliable alternative to expert assessment. Moderate uptake of optional CME content limited evaluation.


Asunto(s)
Radioterapia de Intensidad Modulada , Neoplasias del Cuello Uterino , Educación Médica Continua , Femenino , Humanos , Estudios Prospectivos , Planificación de la Radioterapia Asistida por Computador , Estudios Retrospectivos , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/radioterapia
19.
Semin Radiat Oncol ; 30(4): 311-327, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32828387

RESUMEN

The last 2 decades have witnessed the development and broad adoption of image-guided adaptive brachytherapy (IGABT) combined with radiochemotherapy in patients with locally advanced cervical cancer. A variety of brachytherapy techniques and dose/fractionation schedules have been applied, and until recently, there was no strong evidence available for preferring one approach to another. However, large volumes of data have now provided high level clinical evidence for dose-effect relations for both disease and morbidity endpoints. It is therefore now possible to apply evidence based dose planning aims and dose prescription protocols in IGABT for locally advanced cervical cancer. This review gives an overview of targets/organs-at-risk and disease/morbidity endpoints which are relevant in the context of treatment planning and dose prescription in IGABT. The dosimetric and clinical evidence is summarized to support the implementation of dose prescription protocols which include hard and soft constraints for targets and organs at risk.


Asunto(s)
Braquiterapia/métodos , Quimioradioterapia/métodos , Dosificación Radioterapéutica , Neoplasias del Cuello Uterino/terapia , Femenino , Humanos , Estadificación de Neoplasias , Órganos en Riesgo , Planificación de la Radioterapia Asistida por Computador , Radioterapia Guiada por Imagen/métodos , Carga Tumoral , Neoplasias del Cuello Uterino/patología
20.
Brachytherapy ; 19(6): 837-849, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32978080

RESUMEN

In 2008, the GEC ESTRO Gyn network launched the first multiinstitutional, observational, and prospective international study on MRI-guided brachytherapy in locally advanced cervical cancer patients (EMBRACE-I). EMBRACE-I was followed by EMBRACE-II from 2016 and ongoing. Among the aims of the EMBRACE studies are to benchmark morbidity outcomes and develop dose-volume effects and predictive models for morbidity. The EMBRACE studies collect both physician (CTCAE v.3) and patient (EORTC QLQ-C30/CX24) reported outcomes, including baseline information, in a regular follow-up schedule. The EMBRACE studies feature high numbers of patients (EMBRACE-I N = 1416, EMBRACE-II N = 1500 expected) enrolled from many institutions worldwide (EMBRACE-I n = 23, EMBRACE-II n = 45). This large-scale multiinstitutional approach offers a unique opportunity to investigate and develop new strategies for improving the quality of assessment and reporting of morbidity. This report presents an overview of the challenges and pitfalls regarding the assessment and reporting of morbidity encountered during more than a decade of development and research activities within the EMBRACE consortium. This includes the recognition and evaluation of inconsistencies in the morbidity assessment, and consequently, the provision of assistance and training in the scoring procedure to reduce systematic assessment bias. In parallel, a variety of methodological approaches were tested to comprehensively summarize morbidity outcomes, and a novel approach was developed to refine dose-effect models and risk factor analyses. The purpose of this report is to present an overview of these findings, describe the learning process, and the strategies that have consequently been implemented regarding educational activities, training, and dissemination.


Asunto(s)
Braquiterapia/efectos adversos , Garantía de la Calidad de Atención de Salud , Proyectos de Investigación/normas , Neoplasias del Cuello Uterino/radioterapia , Quimioradioterapia/métodos , Femenino , Humanos , Internacionalidad , Imagen por Resonancia Magnética , Estudios Multicéntricos como Asunto , Estudios Observacionales como Asunto , Medición de Resultados Informados por el Paciente , Radioterapia Guiada por Imagen
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