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1.
Radiother Oncol ; 188: 109887, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37659663

RESUMO

PURPOSE/OBJECTIVE: Deep-inspiration breath-hold (DIBH) during radiotherapy may reduce dose to the lungs and heart compared to treatment in free breathing. However, intra-fractional target shifts between several breath-holds may decrease target coverage. We compared target shifts between four DIBHs at the planning-CT session with those measured on CBCT-scans obtained pre- and post-DIBH treatments. MATERIAL/METHODS: Twenty-nine lung cancer and nine lymphoma patients were treated in DIBH. An external gating block was used as surrogate for the DIBH-level with a window of 2 mm. Four DIBH CT-scans were acquired: one for planning (CTDIBH3) and three additional (CTDIBH1,2,4) to assess the intra-DIBH target shifts at scanning by registration to CTDIBH3. During treatment, pre-treatment (CBCTpre) and post-treatment (CBCTpost) scans were acquired. For each pair of CBCTpre/post, the target intra-DIBH shift was determined. For lung cancer, tumour (GTV-Tlung) and lymph nodes (GTV-Nlung) were analysed separately. Group mean (GM), systematic and random errors, and GM for the absolute maximum shifts (GMmax) were calculated for the shifts between CTDIBH1,2,3,4 and between CBCTpre/post. RESULTS: For GTV-Tlung, GMmax was larger at CBCT than CT in all directions. GMmax in cranio-caudal direction was 3.3 mm (CT)and 6.1 mm (CBCT). The standard deviations of the shifts in the left-right and cranio-caudal directions were larger at CBCT than CT. For GTV-Nlung and CTVlymphoma, no difference was found in GMmax or SD. CONCLUSION: Intra-DIBH shifts at planning-CT session are generally smaller than intra-DIBH shifts observed at CBCTpre/post and therefore underestimate the intra-fractional DIBH uncertainty during treatment. Lung tumours show larger intra-fractional variations than lymph nodes and lymphoma targets.

2.
Acta Oncol ; 62(11): 1433-1439, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37707506

RESUMO

BACKGROUND: In peripheral lung tumours, stereotactic body radiotherapy (SBRT) is superior to conventional RT. SBRT has also shown high loco-regional control (LC) in centrally located tumours, but there is a high risk of severe toxicity. The STRICTSTARLung trial (NCT05354596) examines if risk-adapted SBRT for central tumours is feasible. In this study, we examined overall survival (OS), Disease-free survival (DSF), LC, and toxicity in patients with central tumours that could have been candidates for SBRT but received conventional RT. MATERIAL AND METHODS: Retrospectively, we evaluated 49 lung cancer patients that between 2008 and 2021 received RT (60-70Gy in 2 Gy fractions) for a solitary tumour or lymph node with a diameter <5cm located <2cm from the bronchial tree, oesophagus, aorta or heart. All tumours were pathologically verified; 30 were primary lung tumours (T1b-T4) and 19 were solitary lymph nodes (T0N1-N2). Chemotherapy was administered as concomitant (29) or sequential (4). OS and LC were analysed using Kaplan Meier. Cox proportional hazards model for OS and disease-free survival (DFS) was performed including tumour volume, histology, sex, T- vs N-site and chemotherapy. Toxicity was scored. RESULTS: In 42 patients, the tumour was located <1 cm to mediastinum. Median follow-up time was 44 months (range: 7-123). The median OS was 51 months. OS at 1-, 3- and 5-year was 88% (SE:5), 59% (SE:7) and 50% (SE:8). Loco-regional recurrences occurred in 16 patients resulting in 1-, and 3-year LC rates of 77% (SE:6) and 64% (SE:8). The majority occurred within 3 years after RT. Only stage showed significant impact on OS and DFS. No patients experienced grade 4-5 toxicity. Seven patients developed grade 3 toxicity (5 oesophageal stenosis, 2 pneumonitis). CONCLUSION: Conventional RT for patients with small central lung tumours or solitary lymph nodes is feasible. Median OS was 51 months, and toxicity was low with no grade 4-5 events.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radiocirurgia , Humanos , Estudos Retrospectivos , Neoplasias Pulmonares/patologia , Intervalo Livre de Doença , Radiocirurgia/métodos , Linfonodos/patologia , Resultado do Tratamento
3.
Radiother Oncol ; 173: 102-108, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35667574

RESUMO

INTRODUCTION: The aim was to evaluate and compare the dosimetric effect and robustness towards day-to-day anatomical and setup variations in the delivered dose for photon and proton treatments of sinonasal cancer (SNC) patients. MATERIALS AND METHODS: Photon (VMAT) and proton (IMPT) plans were optimized retrospectively for 24 SNC patients. Synthetic CTs (synCT) were obtained by deforming the planning CT (pCT) to the anatomy of every daily cone-beam CT. Both VMAT and IMPT plans were recalculated on the synCTs. The recalculated daily dose was accumulated over the whole treatment on the pCT. Target coverage and dose to organs and risk (OARs) were evaluated for all patients for the nominal, daily and accumulated dose distribution. RESULTS: In general, dose to OARs farther away from the target, including brain, chiasm and contralateral optic nerve, was lower for proton plans than photon plans. Whereas, OARs in proximity of the target received a lower dose for photon plans. For proton plans, the target coverage (volume of CTV receiving 95% of prescribed dose), V95%, fell below 99% for 9/24 patients in one or more fractions. For photon plans, 4/24 patients had one or more fractions where V95% fell below 99%. For accumulated doses, V95% was below 99% only in two cases, but above 98% for all patients. CONCLUSION: Photon and proton treatment have different strengths regarding OAR sparing. The robustness was high for both treatment modalities. Patient selection for either proton or photon radiation therapy of SNC patients should be based on a case-by-case comparison.


Assuntos
Neoplasias , Terapia com Prótons , Radioterapia de Intensidade Modulada , Humanos , Órgãos em Risco , Prótons , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos
4.
Radiother Oncol ; 171: 53-61, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35421513

RESUMO

INTRODUCTION: SBRT of central lung tumours implies significant risk of toxicity. We are initiating two phase II trials prescribing 56 Gy/eight fractions to PTV, allowing for dose escalation of GTV. We prioritize organs at risk (OAR) constraints over target coverage, making the treatment plans very sensitive to OAR delineation variations. The aim of this study is to quantify the dosimetric impact of contouring variations and to provide a thorough description of pre-trial quality assurance to be used in upcoming trials to provide consistent clinical care. MATERIALS AND METHODS: Delineation: Seven physicians delineated OAR in three rounds, with evaluations in-between. For each patient case, seven treatment plans, repeatedly using each of the OAR structure sets from the seven physicians, were made and compared to evaluate the dosimetric effect of delineation variability. Treatment planning: Treatment plans for seven cases were made at six departments in two rounds, with discussion in-between. RESULTS: OAR delineation variation between centres resulted in high variabilities in OAR dose for simulated plans and led to potential overdosage of the lobar bronchus (constraint: D0.03cc < 45 Gy), with maximum doses ranging between 58 Gy (first round), and 50 Gy (third round). For mediastinal tissue, the constraint (D0.03cc < 45 Gy) was violated for the majority of the delineations in all three rounds, with maximum doses of 84 Gy (first round), and 72 Gy (third round).For the treatment planning study, the range of the standard deviation for GTV mean dose was 12.8-18.5 Gy (first round) and 2.8-3.5 Gy (second round). CONCLUSIONS: Even small variations in OAR delineation led to high OAR overdosage. The study demonstrates the importance of having extensive QA procedures in place before initiating clinical trials on dose escalation in SBRT.


Assuntos
Neoplasias Pulmonares , Radiocirurgia , Radioterapia de Intensidade Modulada , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Órgãos em Risco , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos
6.
Acta Oncol ; 60(3): 353-360, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33522851

RESUMO

BACKGROUND: In radiotherapy (RT) of lung cancer, dose to functional lung (FL) volumes segmented with two different methods (perfusion SPECT (Q-SPECT) and 4D-CT (4D) ventilation (V)) have been shown to correlate with the incidence of radiation pneumonitis (RP). This study aims to compare the FL volumes identified by both methods. MATERIAL AND METHODS: Thirty lung cancer patients had a 4D and Q-SPECT prior to treatment. Seventeen of these patients also had a ventilation SPECT (V-SPECT). FL sub-volumes were segmented automatically, using cut-off values. The volumes were compared in terms of overlap fraction (OF) relative to the minimal volume, and intersection fraction (IF) of the FL volume relative to the total lung volume (VLung). RESULTS: Cut-off values suggested in literature for Q-SPECT and 4D-V resulted in volumes differing in size by a median 18% [6%;31%], and a median OF and IF of 0.48 [0.23;0.70] and 0.09 [0.02;0.25], respectively. Segmenting volumes of comparable size of about 1/3 of VLung (FL-m(1/3), m = method) resulted in a median OF and IF of 0.43 [0.23;0.58] and 0.12 [0.06;0.19], respectively. Twenty-five patients (83%) had a reasonable overlap between FL-Q(1/3) and FL-4D-V(1/3) volumes, with OF values above 0.33. IF increased significantly (p = .036) compared to using fixed cut-off values. Similarly, volumes of comparable size of about 1/3 VLung were produced for V-SPECT, and FL-Q(1/3), FL-V(1/3), and FL-4D-V(1/3) were compared. The overlaps and intersections of FL-V(1/3) with FL-Q(1/3) volumes were significantly (p<.001) larger than the corresponding overlaps and intersections of FL-Q(1/3) with FL-4D(1/3) and FL-V(1/3) with FL-4D(1/3). CONCLUSION: The Q-SPECT and 4D-V methods do not segment entirely the same FL volumes. A reasonable overlap of the volumes along with the findings of other studies that both correlate to RP incidence, suggests that a combination of both volumes, e.g. using the IF, may be useful in RT treatment planning.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Pneumonite por Radiação , Tomografia Computadorizada Quadridimensional , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Pneumonite por Radiação/etiologia , Tomografia Computadorizada de Emissão de Fóton Único
7.
Acta Oncol ; 60(3): 293-299, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33306422

RESUMO

BACKGROUND: Lung cancer patients struggle with high toxicity rates. This study investigates if IMRT plans with individually set beam angles or uni-lateral VMAT plans results in dose reduction to OARs. We investigate if introduction of a RapidPlan model leads to reduced dose to OARs. Finally, the model is validated prospectively. MATERIAL AND METHODS: Seventy-four consecutive lung cancer patients treated with IMRT were included. For all patients, new IMRT plans were made by an experienced dose planner re-tuning beam angles aiming for minimized dose to the lungs and heart. Additionally, VMAT plans were made. The IMRT plans were selected as input for a RapidPlan model, which was used to generate 74 new IMRT plans. The new IMRT plans were used as input for a second RapidPlan model. This model was clinically implemented and used for generation of clinical treatment plans. Dosimetric parameters were compared using a Wilcoxon signed rank test or a 1-sided student's t-test. p < .05 was considered significant. RESULTS: IMRT plans significantly reduced mean doses to lungs (MLD) and heart (MHD) by 1.6 Gy and 1.7 Gy in mean compared to VMAT plans. MLD was significantly (p < .001) reduced from 10.8 Gy to 9.4 Gy by using the second RapidPlan model. MHD was significantly (p < .001) reduced from 4.9 Gy to 3.9 Gy. The model was validated in prospectively collected treatment plans showing significantly lower MLD after the implementation of the second RapidPlan model. CONCLUSION: Introduction of RapidPlan and beam angles selected based on the target and OARs position reduces dose to OARs.


Assuntos
Neoplasias Pulmonares , Radioterapia de Intensidade Modulada , Humanos , Neoplasias Pulmonares/radioterapia , Órgãos em Risco , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
8.
Phys Rev Lett ; 124(8): 082501, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32167344

RESUMO

We present a high-accuracy calculation of the deuteron structure radius in chiral effective field theory. Our analysis employs the state-of-the-art semilocal two-nucleon potentials and takes into account two-body contributions to the charge density operators up to fifth order in the chiral expansion. The strength of the fifth-order short-range two-body contribution to the charge density operator is adjusted to the experimental data on the deuteron charge form factor. A detailed error analysis is performed by propagating the statistical uncertainties of the low-energy constants entering the two-nucleon potentials and by estimating errors from the truncation of the chiral expansion as well as from uncertainties in the nucleon form factors. Using the predicted value for the deuteron structure radius together with the very accurate atomic data for the difference of the deuteron and proton charge radii we, for the first time, extract the charge radius of the neutron from light nuclei. The extracted value reads r_{n}^{2}=-0.106_{-0.005}^{+0.007} fm^{2} and its magnitude is about 1.7σ smaller than the current value given by the Particle Data Group. In addition, given the high accuracy of the calculated deuteron charge form factor and its careful and systematic error analysis, our results open the way for an accurate determination of the nucleon form factors from elastic electron-deuteron scattering data measured at the Mainz Microtron and other experimental facilities.

9.
Med Phys ; 45(10): 4355-4363, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30129041

RESUMO

PURPOSE: When treating lung cancer patients with intensity-modulated proton therapy (IMPT), target coverage can only be guaranteed when utilizing motion mitigation. The three motion mitigation techniques, gating, breath-hold, and dose repainting, all benefit from a more rapid application of the treatment plan. A lower limit for the ungated treatment time is defined by the number of energy layers in the IMPT plan. By limiting this number during treatment planning, IMPT could become more viable for lung cancer patients. We investigate to what extend the number of layers can be reduced in single-field optimization (SFO) and multifield optimization (MFO) plans and which implications it has on the plan quality and robustness. METHODS: We have implemented three distinct layer-reducing strategies in the treatment planning system Hyperion; constant energy steps, exponential energy steps, and an adaptive strategy, where the spot weights are exposed to a group sparsity penalty in combination with layer exclusion during optimization. Four levels of increasing layer removal are planned for each strategy. SFO and MFO plans with three treatment fields are created for eleven locally advanced NSCLC patients on the midventilation 4DCT phase to simulate a breath-hold. A minimum dose to the target is ensured for each degree of layer reduction, reflecting the plan quality in the homogeneity index (HI). Plan quality was also assessed by a robustness evaluation, where the patient setup was shifted 2 mm or 4 mm in six directions. RESULTS: The three strategies result in very similar target coverages and robustness levels as a function of removed layers. The HI increases unacceptably for all the SFO plans after 50% layer removal as compared to the reference plan, while all the MFO plans are clinically acceptable with up to a highest removed percentage of 75%. The robustness level is constant as a function of removed layers. The SFO plans are significantly more robust than the MFO plans with all P-values below 0.001 (Wilcoxon signed-rank). The overall mean D98% CTV dose difference is at 2-mm setup error amplitude: 0.7 Gy (SFO) and 1.9 Gy (MFO), and at 4 mm: 3.2 Gy (SFO) and 5.4 Gy (MFO), respectively. CONCLUSIONS: The number of layers in MFO plans can be reduced substantially more than in SFO plans without compromising plan quality. Furthermore, as the robustness is independent of the number of layers, it follows that if the level of robustness is acceptable or enforced via robust optimization, MFO plans could be candidates for treatment time reductions via energy layer reductions.


Assuntos
Neoplasias Pulmonares/radioterapia , Terapia com Prótons/métodos , Radioterapia de Intensidade Modulada/métodos , Humanos , Órgãos em Risco/efeitos da radiação , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/efeitos adversos
10.
Lett Appl Microbiol ; 67(3): 226-234, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29927502

RESUMO

Streptomyces cinnamonensis A495 is a variant of the monensin producer which instead of the native polyether antibiotic gives rise to antibiotic and anti-tumour shunt-product premonensin. Through the supplementation of the fermentation medium with suitable precursors, premonensin can be derivatized via the incorporation of new-to-nature extender units into the biosynthetic machinery. Polyketide extender units require activation, typically in form of coenzyme A-thioesters. These are membrane impermeable and thus in the past an artificial mimic was employed. Here, we show the use and preliminary characterization of a highly substrate promiscuous new enzyme for the endogenous thioester formation in a Streptomyces strain. These intracellularly activated alternative extender units are significantly better incorporated into premonensin than the synthetically activated counterparts. SIGNIFICANCE AND IMPACT OF THE STUDY: Polyketide natural products are of enormous relevance in medicine. The hit-rate in finding active compounds for the potential treatment of various diseases among this substance family of microbial origin is high. However, most polyketides require derivatization to render them suitable for the application. Of relevance in this field is the incorporation of artificial substances into the biogenesis of polyketides, hampered by both the microbial metabolism and the complexity of the enzymes involved. This manuscript describes the straightforward and selective biosynthetic incorporation of synthetic substances into a reduced polyketide and showcases a promising new enzyme to aid this purpose.


Assuntos
Antibacterianos/biossíntese , Proteínas de Bactérias/metabolismo , Monensin/biossíntese , Policetídeo Sintases/metabolismo , Streptomyces/metabolismo , Proteínas de Bactérias/genética , Vias Biossintéticas , Ativação Enzimática , Fermentação , Policetídeo Sintases/genética , Streptomyces/enzimologia , Streptomyces/genética
11.
QJM ; 111(4): 217-224, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29237089

RESUMO

BACKGROUND/INTRODUCTION: Sarcoidosis is a multi-systemic disorder of unknown etiology, characterized by the presence of non-caseating granulomas in target organs. In 90% of cases, there is thoracic involvement. Fifty to seventy percent of pulmonary sarcoidosis patients will experience acute, self-limiting disease. For the subgroup of patients who develop persistent disease, no targeted therapy is currently available. AIM: To investigate the potential of the single nucleotide polymorphism (SNP), Toll-like receptor 3 Leu412Phe (TLR3 L412F; rs3775291), as a causative factor in the development of and in disease persistence in pulmonary sarcoidosis. To investigate the functionality of TLR3 L412F in vitro in primary human lung fibroblasts from pulmonary sarcoidosis patients. DESIGN: SNP-genotyping and cellular assays, respectively, were used to investigate the role of TLR3 L412F in the development of persistent pulmonary sarcoidosis. METHODS: Cohorts of Irish sarcoidosis patients (n = 228), healthy Irish controls (n = 263) and a secondary cohort of American sarcoidosis patients (n = 123) were genotyped for TLR3 L412F. Additionally, the effect of TLR3 L412F in primary lung fibroblasts from pulmonary sarcoidosis patients was quantitated following TLR3 activation in the context of cytokine and type I interferon production, TLR3 expression and apoptotic- and fibroproliferative-responses. RESULTS: We report a significant association between TLR3 L412F and persistent clinical disease in two cohorts of Irish and American Caucasians with pulmonary sarcoidosis. Furthermore, activation of TLR3 in primary lung fibroblasts from 412 F-homozygous pulmonary sarcoidosis patients resulted in reduced IFN-ß and TLR3 expression, reduced apoptosis- and dysregulated fibroproliferative-responses compared with TLR3 wild-type patients. DISCUSSION/CONCLUSION: This study identifies defective TLR3 function as a previously unidentified factor in persistent clinical disease in pulmonary sarcoidosis and reveals TLR3 L412F as a candidate biomarker.


Assuntos
Polimorfismo de Nucleotídeo Único , Sarcoidose Pulmonar/genética , Receptor 3 Toll-Like/genética , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Irlanda , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fenótipo , Adulto Jovem
12.
Chirurg ; 89(5): 347-357, 2018 May.
Artigo em Alemão | MEDLINE | ID: mdl-29075796

RESUMO

BACKGROUND: In the last decade the implementation of the new technique of endoscopic submucosal dissection (ESD) and the rapid progression of laparoscopic gastric cancer (LAG) resection with an adequate lymphadenectomy (LAD) have played an increasing role in the treatment of patients with early stage gastric cancer (EGC). OBJECTIVE: A systematic review of the currently available data in the literature was carried out to evaluate the contemporary surgical management for treatment of EGC. RESULTS: Endoscopic resection (ER) of mucosal T1 gastric cancer (T1m) in accordance with the German guidelines on resection criteria is a widely accepted treatment option, if a definitive R0 resection can be achieved. Excellent en bloc and R0 results in more than 90% of these cases have been shown particularly for ESD. In contrast to T1m gastric carcinomas with a low risk of lymph node metastases (approximately 3%), nodal involvement reaches more than 20% for submucosal infiltrated EGC (T1sm). For this reason, a surgical resection with adequate LAD is further recommended in all cases of non-curative ER or any T1sm gastric cancer. In seven randomized controlled trials and a series of meta-analyses including high-quality non-randomized trials, significant benefits in short-term postoperative outcome have been demonstrated for LAG in comparison to open gastrectomy (OG) in the treatment of EGC. The general morbidity was also significantly lower in LAG than in OG. The 30-day mortality and long-term survival outcome were comparable between the two groups. CONCLUSION: The use of ESD should be the standard treatment for T1m EGC within the guidelines criteria. For non-curative ESD and T1sm gastric cancer, surgical resection with LAD is recommended. The LAG is a technically safe, feasible, and favorable approach in terms of faster recovery compared to OG. The long-term survival outcome is comparable between LAG and OG for EGC.


Assuntos
Ressecção Endoscópica de Mucosa , Gastrectomia , Neoplasias Gástricas , Mucosa Gástrica , Humanos , Excisão de Linfonodo , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Neoplasias Gástricas/cirurgia , Resultado do Tratamento
13.
Acta Psychiatr Scand ; 136(6): 559-570, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28422269

RESUMO

OBJECTIVE: To examine the efficacy of using wake and light therapy as a supplement to standard treatment of hospitalized patients with depression. METHOD: In this randomized, controlled study, 64 patients with moderate-to-severe depression were allocated to standard treatment or to the intervention, which additionally consisted of three wake therapy sessions in one week, 30-min daily light treatment and sleep time stabilization over the entire nine-week study period. RESULTS: Patients in the wake therapy group had a significant decrease in depressive symptoms in week one as measured by HAM-D17 , 17.39 (CI 15.6-19.2) vs. 20.19 (CI 18.3-22.09) (P = 0.04), whereas no statistically significant differences were found between the groups in weeks two to nine. At week nine, the wake therapy group had a significantly larger increase in general self-efficacy (P = 0.001), and waking up during nights was a significantly less frequent problem (1.9 times vs. 3.2) (P = 0.0008). In most weeks, significantly fewer patients in the wake therapy group slept during the daytime, and if they slept, their naps were shorter (week three: 66 min vs. 117 min P = 0.02). CONCLUSION: The antidepressant effect initially achieved could not be maintained during the nine-week study period. However, sleep and general self-efficacy improved.


Assuntos
Transtorno Depressivo/terapia , Fototerapia/métodos , Adulto , Idoso , Transtorno Depressivo Maior/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autoeficácia , Índice de Gravidade de Doença , Resultado do Tratamento , Vigília , Adulto Jovem
14.
Phys Med Biol ; 62(8): 3250-3262, 2017 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-28350545

RESUMO

Dose volume histogram points (DVHPs) frequently serve as dose constraints in radiotherapy treatment planning. An experiment was designed to investigate the reliability of DVHP inference from clinical data for multiple cohort sizes and complication incidence rates. The experimental background was radiation pneumonitis in non-small cell lung cancer and the DVHP inference method was based on logistic regression. From 102 NSCLC real-life dose distributions and a postulated DVHP model, an 'ideal' cohort was generated where the most predictive model was equal to the postulated model. A bootstrap and a Cohort Replication Monte Carlo (CoRepMC) approach were applied to create 1000 equally sized populations each. The cohorts were then analyzed to establish inference frequency distributions. This was applied to nine scenarios for cohort sizes of 102 (1), 500 (2) to 2000 (3) patients (by sampling with replacement) and three postulated DVHP models. The Bootstrap was repeated for a 'non-ideal' cohort, where the most predictive model did not coincide with the postulated model. The Bootstrap produced chaotic results for all models of cohort size 1 for both the ideal and non-ideal cohorts. For cohort size 2 and 3, the distributions for all populations were more concentrated around the postulated DVHP. For the CoRepMC, the inference frequency increased with cohort size and incidence rate. Correct inference rates >[Formula: see text] were only achieved by cohorts with more than 500 patients. Both Bootstrap and CoRepMC indicate that inference of the correct or approximate DVHP for typical cohort sizes is highly uncertain. CoRepMC results were less spurious than Bootstrap results, demonstrating the large influence that randomness in dose-response has on the statistical analysis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Pneumonite por Radiação/prevenção & controle , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Modelos Logísticos , Método de Monte Carlo , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/normas , Reprodutibilidade dos Testes , Tamanho da Amostra , Incerteza
15.
Sportverletz Sportschaden ; 29(4): 236-43, 2015 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-26579625

RESUMO

BACKGROUND: Studies have shown changes in the technical and physical demands in modern handball. The game has increased considerably in speed, power and dynamics. Jump training has, therefore, become ever more important in the training of the athletes. These developments contribute to the fact that handball is now one of the most injury-prone types of sport, with the lower extremities being most frequently affected. Reactive jump training is not only used in training by now, but also increasingly in injury prevention. The aim of this study was to investigate the effectiveness of reactive jump training with handball players. MATERIAL AND METHODS: 21 regional league handball players were randomly divided into an intervention group (n = 12) and a control group (n = 9). The intervention group completed a six-week reactive jump training programme while the control group went through a non-specific training programme. Jump height (squat and counter movement jump), isokinetic and isometric maximum power as well as muscle activity served as measuring parameters. RESULTS: A comparison of the intervention and control groups revealed that the reactive jump training led to significant improvements in jump height. The isometric and isokinetic maximum power measurements and the electromyographic activities of the triceps surae muscle demonstrated an improvement in the values within the intervention group. However, this improvement was not significant compared with the control group. Likewise both jumps correlated with the muscle activity of the soleus muscle as shown by electromyography. A moderate correlation was noticed between the isokinetic maximum power measurement and the electromyographic activity of the soleus and gastrocnemius medialis muscles. Furthermore, the correlations of the isometric and isokinetic maximum power meas-urements resulted in a strong correlation coefficient. CONCLUSION: This study revealed a significant increase in jump height after reactive jump training. There was no significant difference in power development between the two groups. However, we were able to demonstrate correlations which would make it seem reasonable and interesting to investigate the question more closely. An interesting field of research could be the question of the effectiveness of reactive jump training in the areas of rehabilitation and injury prevention.


Assuntos
Desempenho Atlético/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Condicionamento Físico Humano/métodos , Esportes/fisiologia , Adulto , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento , Adulto Jovem
16.
Z Geburtshilfe Neonatol ; 219(2): 93-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25525815

RESUMO

BACKGROUND: The demographic change in -Germany describes an ongoing process of population development of which the eastern German states tend to be more affected. These ongoing changes have an influence on the reproductive behavior of the population. After twenty-three years of German reunification, the present study has investigated the question to what extent the somatic classification of newborns in Mecklenburg-Pomerania (M-P), Germany, is affected. MATERIAL AND METHODS: Newborn singleton births (n=174,084) were classified from the existing data of the German Perinatal Survey between 1994 and 2011. The rate of premature birth, SGA, and LGA rate as well as the rate of low birth weight ≤2,499 g were determined both gender-dependently and independently. In addition, a combined analysis of the rates has been taken into account. The obtained data material from M-P made it possible for the first time to compare by values. National and international reference studies were considered in this comparison. RESULTS: In M-P, the premature birth rate is 5.2%; the rate of newborns with low birth weight ≤ 2,499 g is 4.4%. Among newborns of ≤2,499 g and SGA newborns, girls compose a higher percentage (4.7%, 12.5%) compared to boys (4.0%, 7.4%). The premature birth rate and LGA newborns appear conversely. For these, the percentage of boys (5.6%, 12.6%) is higher than that of girls (4.8%, 7.0%). 60.6% of the gender non-specific newborns ≤2,499 g are simultaneously premature newborn infants. Only a very small percentage of 0.5% of SGA newborns is at the same time premature infants and newborns with low birth weight. CONCLUSIONS: By getting nationwide country-specific figures, a detailed analysis of the newborns in M-P can be performed. The analysis supports the existing national values and is a helpful addition for practice-oriented advice.


Assuntos
Peso Corporal/fisiologia , Idade Gestacional , Resultado da Gravidez/epidemiologia , Gravidez/fisiologia , Gravidez/estatística & dados numéricos , Nascimento Prematuro/epidemiologia , Coeficiente de Natalidade , Feminino , Alemanha/epidemiologia , Pesquisas sobre Atenção à Saúde , Humanos , Recém-Nascido de Baixo Peso/fisiologia , Prevalência , Distribuição por Sexo
17.
Clin Exp Immunol ; 178(2): 342-52, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24962673

RESUMO

Sarcoidosis is a granulomatous disorder of unknown aetiology. The presence of Mycobacterium tuberculosis catalase-peroxidase (mKatG) in sarcoidosis tissue has been reported. T helper type 1 (Th1) responses against mKatG have previously been observed. However, little is known about interleukin (IL)-17 and Th17 responses in sarcoidosis. Here, we investigated the levels of IL-17 and frequencies of IL-17-producing cells responding to mKatG in sarcoidosis patients with different prognosis. Peripheral blood and bronchoalveolar lavage (BAL) cells were obtained from sarcoidosis patients with or without Löfgren's syndrome (often associated with spontaneous recovery), and also stratified according to human leucocyte antigen (HLA) type. Cells producing IL-17 and interferon (IFN)-γ after stimulation with mKatG were enumerated by enzyme-linked immunospot (ELISPOT). The level of IL-17 in the BAL fluid of sarcoidosis patients and healthy controls was measured by quantitative immuno-polymerase chain reaction (qIPCR). We also performed flow cytometry and immunohistochemistry for further characterization of IL-17 expression. Patients with Löfgren's syndrome had a higher frequency of IL-17-producing cells responding to mKatG in BAL fluid compared to patients without Löfgren's syndrome (P < 0·05). The HLA-DR3(+) sarcoidosis patients with Löfgren's syndrome (known to have a particularly good prognosis) also had a clearly higher level of IL-17 in BAL fluid compared to healthy controls and sarcoidosis patients without Löfgren's syndrome (P < 0·01) and (P < 0·05), respectively. No such difference between patient groups was observed with regard to IFN-γ and not with regard to either cytokine in peripheral blood. These findings suggest that IL-17-producing cells may be a useful biomarker for the prognosis of sarcoidosis and play a role in the spontaneous recovery typical of patients with Löfgren's syndrome.


Assuntos
Interleucina-17/metabolismo , Sarcoidose Pulmonar/imunologia , Sarcoidose Pulmonar/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Adulto , Proteínas de Bactérias/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Catalase/imunologia , Feminino , Expressão Gênica , Antígeno HLA-DR3/imunologia , Humanos , Interleucina-17/genética , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Sarcoidose Pulmonar/diagnóstico , Sarcoidose Pulmonar/genética , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
18.
Gesundheitswesen ; 76(4): 204-9, 2014 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-23913395

RESUMO

OBJECTIVE: The following study examines the influencing factors on the satisfaction of oncological patients with their primary care physician, specialist physician, hospital and health insurance provider. Individual patient satisfaction with cross-sectoral collaboration is examined based on the satisfaction with these sectors. METHOD: 12 specialist practices from 8 federal states participated in the patient survey. Altogether, 516 patients took part during the investigation period 2011-2012. The results were evaluated by multiple regression analysis. RESULTS: The results show that patients are content with cross-sectoral collaboration if they are satisfied with their health insurance and the specialist physician. With regard to satisfaction with the primary care physician and the specialist physician, trust is perceived to be the most important influencing factor. For hospitals, the most significant influencing factor is interest in and time for patients. Regarding health insurance, providing the patients with information leads to a greater degree of satisfaction. CONCLUSION: Psychosocial factors are of key importance for the patient's perceptions of satisfaction with the different sectors. This contains for instance factors like to 'putting confidence in physicians' or 'talking about patients' fears'. The sectors considered in this study should therefore give more consideration to these factors during patient care. A health insurance provider can take on the role of a competent point of contact, providing quality-assured information in the context of oncological diseases.


Assuntos
Hospitalização/estatística & dados numéricos , Seguro Saúde/estatística & dados numéricos , Neoplasias/epidemiologia , Neoplasias/psicologia , Satisfação do Paciente/estatística & dados numéricos , Relações Médico-Paciente , Médicos de Atenção Primária/psicologia , Adulto , Idoso , Atitude Frente a Saúde , Feminino , Alemanha/epidemiologia , Setor de Assistência à Saúde/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto/estatística & dados numéricos , Fatores Socioeconômicos , Especialização/estatística & dados numéricos
19.
Neuroscience ; 254: 173-84, 2013 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-24060822

RESUMO

Neurogenesis continues to occur in restricted regions of the brain throughout adulthood and can be modulated by dietary factors. Liquid or "soft" diets are commonly used for the administration of drugs in experimental models of disease, making it critical to determine whether dietary composition itself can affect neurogenesis. In this study Sprague-Dawley rats were fed either a liquid or a solid diet of identical composition from weaning until young adulthood. No differences in neuronal differentiation and survival of newly born cells were observed between rats that were fed a liquid diet and those that received a solid diet. However, a significant reduction in hippocampal cell proliferation was observed in the liquid diet-fed group, as assessed by the expression of two endogenous proliferation markers, Ki67 and proliferating cell nuclear antigen (PCNA). The method of feeding did not alter the basal function of the hypothalamic-pituitary-adrenal (HPA) axis in these animals, as no changes in circulating levels of corticosterone (CORT) were detected between liquid and solid diet-fed groups. There was also a significant reduction in cellular proliferation in the hypothalamus of liquid diet-fed rats, a brain region known to be involved in feeding-related behaviors. These findings indicate that liquid diets themselves can directly impact rates of cellular proliferation, but this does not seem to impact levels of overall neurogenesis in the adult brain.


Assuntos
Proliferação de Células , Alimentos Formulados/efeitos adversos , Hipocampo/citologia , Hipocampo/fisiologia , Neurogênese/fisiologia , Fatores Etários , Animais , Proteína Duplacortina , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
20.
J Pharmacol Exp Ther ; 347(1): 57-68, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23863695

RESUMO

Dopaminergic, serotonergic, and adrenergic receptors are targets for therapeutic actions in schizophrenia. Dopamine D2 receptor partial agonists such as aripiprazole represent a treatment option for patients with this severe disorder. The ineffectiveness of terguride, another D2 receptor partial agonist, in treating schizophrenia was recently attributed to its considerably high intrinsic activity at D2 receptors. In this study, we used functional assays for recombinant D2 receptors and native 5-hydroxytryptamine 2A (5-HT2A), α2C-adrenergic, and histamine H1 receptors to compare the pharmacological properties of terguride and three of its halogenated derivatives (2-chloro-, 2-bromo-, 2-iodoterguride) with those of aripiprazole. Subsequently, we studied the antidopaminergic effects of 2-bromoterguride using amphetamine-induced locomotion (AIL). Its influence on spontaneous behavior was tested in the open field. Extrapyramidal side effect (EPS) liability was evaluated by catalepsy test. In a guanosine 5'-O-(3-[(35)S]thio)triphosphate ([(35)S]GTPγS) binding assay, 2-chloro-, 2-bromo-, and 2-iodoterguride produced intrinsic activities at human D2short (hD2S) receptors that were half as high as the intrinsic activity for terguride; aripiprazole lacked agonist activity. 2-Bromoterguride and aripiprazole activated D2S receptor-mediated inhibition of cAMP accumulation to the same extent; intrinsic activity was half as high as that of terguride. All compounds tested behaved as antagonists at human D2long/Gαo (hD2L/Gαo) receptors. Compared with aripiprazole, terguride and its derivatives displayed higher affinity at porcine 5-HT2A receptors and α2C-adrenoceptors and lower affinity at H1 receptors. 2-Bromoterguride inhibited AIL and did not induce catalepsy in rats. Because of its in vitro and in vivo properties, 2-bromoterguride may be a strong candidate for the treatment of schizophrenia with a lower risk to induce EPS.


Assuntos
Antipsicóticos/administração & dosagem , Antipsicóticos/metabolismo , Agonistas de Dopamina/metabolismo , Lisurida/análogos & derivados , Receptor 5-HT2A de Serotonina/metabolismo , Receptor 5-HT2C de Serotonina/metabolismo , Receptores de Dopamina D2/metabolismo , Animais , Células CHO , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/metabolismo , Cricetinae , Cricetulus , Agonistas de Dopamina/química , Agonistas de Dopamina/farmacologia , Células HEK293 , Humanos , Lisurida/química , Lisurida/metabolismo , Lisurida/farmacologia , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Técnicas de Cultura de Órgãos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D2/agonistas , Suínos
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