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1.
Strahlenther Onkol ; 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37638976

RESUMO

PURPOSE: Demographic change will lead to an increase in age-associated cancers. The demand for primary treatment, especially oncologic therapies, is difficult to predict. This work is an attempt to project the demand for radiation therapy (RT) in 2030, taking into account demographic changes using prostate cancer (PC) as an example. MATERIALS AND METHODS: Using the GENESIS database of the Federal Statistical Office, we retrieved demographic population projections for 2030 and retrospective demographic surveys from 1999 to 2019. Additionally, we queried incidence rates for PC in the respective age groups of 50-54, 55-59, 60-64, 65-69, 70-74, 75-79, 80-84, and +85 years from 1999-2019 via the Federal Cancer Registry of the Robert Koch Institute. We used a regression method to determine the age-dependent correlation between the incidence of PC and the population size of the respective age group by combining the data from 1999 to 2019. This information was used to calculate the incidence rates in the age groups of the expected population for 2030 and the expected new cases of PC in 2030. Finally, we extrapolated the indications for the demand for RT based on data from the Report on Cancer Incidence in Germany from 2016. RESULTS: Considering a population-dependent incidence rate, an increase in new cases of PC is expected. This increase is particularly evident in the age groups of 70-74 and 80-84 years. With regards to RT, the estimate indicates an overall increase of 27.4% in demand. There is also a shift in RT demands towards older patients, especially in the 80- to 84-year-old age group. CONCLUSION: We observe an age-associated increase in primary cases of PC. This is likely to result in an increased demand for RT. The exact demand cannot be predicted. However, trends can be estimated to plan for the demand. This, though, requires a good database from cancer registries.

2.
Phys Rev Lett ; 129(25): 255901, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36608232

RESUMO

Fast-propagating waves in the phase of incommensurate structures, called phasons, have long been argued to enhance thermal transport. Although supersonic phason velocities have been observed, the lifetimes, from which mean free paths can be determined, have not been resolved. Using inelastic neutron scattering and thermal conductivity measurements, we establish that phasons in piezoelectric fresnoite make a major contribution to thermal conductivity by propagating with higher group velocities and longer mean free paths than phonons. The phason contribution to thermal conductivity is maximum near room temperature, where it is the single largest contributing degree of freedom.

3.
Cerebellum ; 17(3): 300-307, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29248983

RESUMO

The vestibulo-ocular reflex maintains gaze stabilization during angular or linear head accelerations, allowing adequate dynamic visual acuity. In case of bilateral vestibular hypofunction, patients use saccades to compensate for the reduced vestibulo-ocular reflex function, with covert saccades occurring even during the head displacement. In this study, we questioned whether covert saccades help maintain dynamic visual acuity, and evaluated which characteristic of these saccades are the most relevant to improve visual function. We prospectively included 18 patients with chronic bilateral vestibular hypofunction. Subjects underwent evaluation of dynamic visual acuity in the horizontal plane as well as video recording of their head and eye positions during horizontal head impulse tests in both directions (36 ears tested). Frequency, latency, consistency of covert saccade initiation, and gain of covert saccades as well as residual vestibulo-ocular reflex gain were calculated. We found no correlation between residual vestibulo-ocular reflex gain and dynamic visual acuity. Dynamic visual acuity performance was however positively correlated with the frequency and gain of covert saccades and negatively correlated with covert saccade latency. There was no correlation between consistency of covert saccade initiation and dynamic visual acuity. Even though gaze stabilization in space during covert saccades might be of very short duration, these refixation saccades seem to improve vision in patients with bilateral vestibular hypofunction during angular head impulses. These findings emphasize the need for specific rehabilitation technics that favor the triggering of covert saccades. The physiological origin of covert saccades is discussed.


Assuntos
Reflexo Vestíbulo-Ocular , Movimentos Sacádicos , Doenças Vestibulares/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Medições dos Movimentos Oculares , Feminino , Teste do Impulso da Cabeça , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Acuidade Visual , Adulto Jovem
4.
Int J Sports Med ; 37(5): 347-53, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26859644

RESUMO

Metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM) are associated with macro- and microcirculatory complications that reduce physical performance. Wearing compression garments to potentially optimize hemodynamics has been discussed. This study investigates the effects of wearing compression stockings on physical performance-related variables in type 2 diabetic men with metabolic syndrome (n=9, 57±12 years, BMI: 36±4 kg/m(2)). Participants served as their own controls in a randomized 3*3 crossover study wearing below-knee stockings with either compression (24 or 30 mmHg ankle pressure) or no compression. Venous pooling and lower limb oxygenation profiles were determined with near-infrared spectroscopy and arterial oxygen saturation was determined using a pulse oxymeter. Measurements were performed in the supine lying position, during standing, following 10 tiptoe exercises and after submaximal intensity cycling. In addition, lactate and erythrocyte deformability were analyzed in capillary blood pre- and post-exercise. Erythrocyte deformability was analyzed using a laser-assisted optical rotational red cell analyzer. No significant differences in any variables when wearing different compression or regular stockings were evident at any point of measurement. This study did not reveal any beneficial effects of wearing compression stockings at rest and during acute bouts of moderately intense exercise in this particular patient group.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Teste de Esforço , Hemodinâmica , Síndrome Metabólica/terapia , Meias de Compressão , Idoso , Estudos Cross-Over , Deformação Eritrocítica , Humanos , Ácido Láctico/sangue , Perna (Membro) , Masculino , Pessoa de Meia-Idade , Oximetria , Consumo de Oxigênio , Descanso , Espectroscopia de Luz Próxima ao Infravermelho , Insuficiência Venosa/terapia
8.
Phys Rev Lett ; 113(14): 147601, 2014 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-25325660

RESUMO

We measured nuclear forward scattering spectra utilizing the (99)Ru transition, 89.571(3) keV, with a notably mixed E2/M1 multipolarity. The extension of the standard evaluation routines to include mixed multipolarity allows us to extract electric and magnetic hyperfine interactions from (99)Ru-containing compounds. This paves the way for several other high-energy Mössbauer transitions, E ∼ 90 keV. The high energy of such transitions allows for operando nuclear forward scattering studies in real devices.

9.
Phys Rev Lett ; 112(2): 025502, 2014 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-24484025

RESUMO

We measured the density of vibrational states (DOS) and the specific heat of various glassy and crystalline polymorphs of SiO2. The typical (ambient) glass shows a well-known excess of specific heat relative to the typical crystal (α-quartz). This, however, holds when comparing a lower-density glass to a higher-density crystal. For glassy and crystalline polymorphs with matched densities, the DOS of the glass appears as the smoothed counterpart of the DOS of the corresponding crystal; it reveals the same number of the excess states relative to the Debye model, the same number of all states in the low-energy region, and it provides the same specific heat. This shows that glasses have higher specific heat than crystals not due to disorder, but because the typical glass has lower density than the typical crystal.

10.
Dis Esophagus ; 27(2): 146-51, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23574528

RESUMO

The aim of this study was to correlate acute organ toxicity during preoperative radiochemotherapy with overall survival and tumor regression for patients with primarily operable esophageal carcinoma. From 1995 to 2002, 60 patients with primarily operable esophageal carcinoma were treated in a preoperative setting at our department. Thirty-three percent of the patients had International Union against Cancer (UICC)-stage II tumors, 62% had UICC-stage III tumors, and 5% had UICC-stage IVA tumors. All patients received irradiation (40 Gy at 2 Gy/fraction). Chemotherapy for all patients with adenocarcinoma and, from 2001, also for patients with squamous cell carcinoma consisted of two cycles, 5-fluorouracil and cisplatinum; between 1995 and 2001, patients with squamous cell carcinoma received three courses of chemotherapy (folinic acid, etoposide, 5-fluorouracil, and cisplatinum every 3 weeks) before and further cisplatinum and etoposide during radiotherapy. We found a significant correlation between acute organ toxicity and histopathological tumor regression, as well as overall survival. The probability to achieve tumor regression grade 1 after radiochemotherapy was nearly four times higher for patients with worsening of odynophagia than for those without an increase (odds ratio: 3.97). Patients with worsening of odynophagia had a 5-year overall-survival rate of 66% compared with 39% in patients without (P = 0.048). Our data indicate that normal tissue and tumor tissue may behave similar with respect to treatment response, as acute organ toxicity showed to be an independent prognostic marker in our patient population. The hypothesis should be further analyzed on biomolecular and clinical level in future clinical trials.


Assuntos
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia/efeitos adversos , Neoplasias Esofágicas/terapia , Mucosite/etiologia , Terapia Neoadjuvante/efeitos adversos , Adenocarcinoma/patologia , Carcinoma de Células Escamosas/patologia , Cisplatino/administração & dosagem , Neoplasias Esofágicas/patologia , Etoposídeo/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Carga Tumoral , Vômito
11.
Int J Sports Med ; 35(13): 1065-71, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25009968

RESUMO

Patients suffering from type 2 diabetes mellitus (T2DM) often exhibit chronic elevated lactate levels which can promote peripheral insulin resistance by disturbing skeletal muscle insulin-signaling. Monocarboxylate transporter (MCT) proteins transfer lactate molecules through cellular membranes. MCT-1 and MCT-4 are the main protein isoforms expressed in human skeletal muscle, with MCT-1 showing a higher affinity (lower Km) for lactate than MCT-4. T2DM patients have reduced membranous MCT-1 proteins. Consequently, the lactate transport between muscle cells and the circulation as well as within an intracellular lactate shuttle, involving mitochondria (where lactate can be further metabolized), can be negatively affected. This study investigates whether moderate cycling endurance training (3 times per week for 3 months) can change skele-tal muscle MCT contents in T2DM men (n=8, years=56±9, body mass index (BMI)=32±4 kg/m(2)). Protein content analyses (immuno-histochemical stainings) were performed in bio-psies taken from the vastus lateralis muscle. Intracellular MCT-1 proteins were up-regulated (relative increase+89%), while intracellular MCT-4 contents were down-regulated (relative decrease - 41%) following endurance training. Sarcolemmal MCT-1 and MCT-4 did not change. The question of whether the training-induced up-regulation of intracellular MCT-1 leads to an improved lactate transport (and clearance) in T2DM patients requires further research.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Educação Física e Treinamento , Resistência Física/fisiologia , Simportadores/metabolismo , Idoso , Índice de Massa Corporal , Humanos , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Masculino , Pessoa de Meia-Idade , Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares de Contração Lenta/metabolismo , Obesidade/metabolismo , Sobrepeso/metabolismo , Regulação para Cima
13.
Strahlenther Onkol ; 188(10): 926-32, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22878546

RESUMO

PURPOSE: The purpose of the current work was to prospectively measure the influence of testicular radiation dose on hormone levels, quality of life (QoL), and sexual functioning following multimodal therapy (neoadjuvant radiochemotherapy, surgery, and adjuvant chemotherapy) for rectal cancer. PATIENTS AND METHODS: From November 2007 to November 2009, 83 male patients were treated at the University of Goettingen with radiochemotherapy (RCT) for locally advanced rectal cancer [total dose 50.4 Gy, concomitant chemotherapy with two cycles of 5-fluorouracil (FU) or 5-FU and oxaliplatin]. Testicular radiation doses were analyzed and correlated with hormone levels [luteinizing hormone (LH), follicle stimulating hormone (FSH), total testosterone and free androgen index (FAI) serum levels], QoL, and sexual functioning, which were determined before and up to 1 year after RCT. RESULTS: Mean dose at the testes was 3.9 Gy (range 0.28-11.98 Gy). It was higher for tumors located < 6 cm from the anocutaneous line (p < 0.05). One year after therapy, testosterone, the testosterone/LH ratio, and the FAI/LH ratio were significantly decreased (3.5-3.0 µg/l, 0.9-0.4, 7.9-4.5, respectively) while LH and FSH (4.2-8.5 IU/l, 6.0-21.9 IU/l) were increased. QoL and sexual functioning were significantly impaired. However, there was no statistical correlation between testicular radiation dose and changes in hormone levels, QoL, or sexual functioning. CONCLUSION: Multimodal treatment for rectal cancer including RCT leads to hormone level changes and to impaired QoL and sexual functioning. However, because there was no apparent correlation between the analyzed parameters, QoL is probably also influenced by other factors, e.g., psychosocial aspects.


Assuntos
Quimiorradioterapia/estatística & dados numéricos , Hormônios Esteroides Gonadais/sangue , Qualidade de Vida , Lesões por Radiação/epidemiologia , Neoplasias Retais/diagnóstico , Neoplasias Retais/radioterapia , Disfunções Sexuais Fisiológicas/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada/estatística & dados numéricos , Comorbidade , Alemanha/epidemiologia , Humanos , Masculino , Especificidade de Órgãos , Prevalência , Dosagem Radioterapêutica , Neoplasias Retais/epidemiologia , Fatores de Risco , Testículo/efeitos da radiação , Resultado do Tratamento
14.
Med Phys ; 49(8): 5347-5362, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35670033

RESUMO

PURPOSE: A clinical implementation of ion-beam radiography (iRad) is envisaged to provide a method for on-couch verification of ion-beam treatment plans. The aim of this work is to introduce and evaluate a method for quantitative water-equivalent thickness (WET) measurements for a specific helium-ion imaging system for WETs that are relevant for imaging thicker body parts in the future. METHODS: Helium-beam radiographs (αRads) are measured at the Heidelberg Ion-beam Therapy Center with an initial beam energy of 239.5 MeV/u. An imaging system based on three pairs of thin silicon pixel detectors is used for ion path reconstruction and measuring the energy deposition (dE) of each particle behind the object to be imaged. The dE behind homogeneous plastic blocks is related to their well-known WETs between 280.6 and 312.6 mm with a calibration curve that is created by a fit to measured data points. The quality of the quantitative WET measurements is determined by the uncertainty of the measured WET of a single ion (single-ion WET precision) and the deviation of a measured WET value to the well-known WET (WET accuracy). Subsequently, the fitted calibration curve is applied to an energy deposition radiograph of a phantom with a complex geometry. The spatial resolution (modulation transfer function at 10 % -MTF10% ) and WET accuracy (mean absolute percentage difference-MAPD) of the WET map are determined. RESULTS: In the optimal imaging WET-range from ∼280 to 300 mm, the fitted calibration curve reached a mean single-ion WET precision of 1.55 ± $\,{\pm}\,$ 0.00%. Applying the calibration to an ion radiograph (iRad) of a more complex WET distribution, the spatial resolution was determined to be MTF10% = 0.49 ± $\,{\pm}\,$ 0.03 lp/mm and the WET accuracy was assessed as MAPD to 0.21 %. CONCLUSIONS: Using a beam energy of 239.5 MeV/u and the proposed calibration procedure, quantitative αRads of WETs between ∼280 and 300 mm can be measured and show high potential for clinical use. The proposed approach with the resulting image qualities encourages further investigation toward the clinical application of helium-beam radiography.


Assuntos
Hélio , Água , Calibragem , Íons , Imagens de Fantasmas , Radiografia
15.
Rev Sci Instrum ; 93(6): 065109, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35778024

RESUMO

CHESS, chopper spectrometer examining small samples, is a planned direct geometry neutron chopper spectrometer designed to detect and analyze weak signals intrinsic to small cross sections (e.g., small mass, small magnetic moments, or neutron absorbing materials) in powders, liquids, and crystals. CHESS is optimized to enable transformative investigations of quantum materials, spin liquids, thermoelectrics, battery materials, and liquids. The broad dynamic range of the instrument is also well suited to study relaxation processes and excitations in soft and biological matter. The 15 Hz repetition rate of the Second Target Station at the Spallation Neutron Source enables the use of multiple incident energies within a single source pulse, greatly expanding the information gained in a single measurement. Furthermore, the high flux grants an enhanced capability for polarization analysis. This enables the separation of nuclear from magnetic scattering or coherent from incoherent scattering in hydrogenous materials over a large range of energy and momentum transfer. This paper presents optimizations and technical solutions to address the key requirements envisioned in the science case and the anticipated uses of this instrument.

16.
Int J Cancer ; 128(9): 2114-24, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21105039

RESUMO

The nuclear protein PLU-1/JARID1B/KDM5 is widely expressed in breast cancers while showing highly restricted expression in normal adult tissues. To investigate whether JARID1B is a potential target antigen for immunotherapy of breast cancer, we have analyzed the responses of CD8(+) T cells to JARID1B HLA-A*0201 peptides in vitro and used peptide multimers to detect the presence of JARID1B reactive T cells in the circulation of breast cancer patients. Peptides were selected using two web-based algorithms: criteria for inclusion being a high score in both prediction algorithms, and nonhomology with retinoblastoma binding protein-2 (RBP2/JARID1A/KDM5A). A 65-peptide panel was selected and assayed for binding strength by competition assay to obtain the IC(50). The immunogenicity in vitro of these peptides was assessed by T cell stimulation experiments, using autologous dendritic cells as APCs in the first rounds followed by autologous lymphoblasts. Fourteen of the peptides assayed produced cultures having >2% of the CD8(+) cells being IFN-γ(+) after 3-6 rounds of stimulation. An HLA-A*0201 cell line could activate the specific T cells if pulsed with peptide, but endogenous peptide levels were insufficient for activation. Nevertheless, multimer staining of circulating T cells from breast cancer patients showed a significantly higher percentage of multimer positive CD8(+) T cells, as compared to healthy adults for two of three JARID1B epitopes tested. One of these, peptide 73 (QLYALPCVL), was analyzed for memory phenotype, and found to have a significantly higher proportion of central memory T cells than the control group, demonstrating a previous exposure to the peptide.


Assuntos
Neoplasias da Mama/imunologia , Linfócitos T CD8-Positivos/imunologia , Antígenos HLA-A/imunologia , Histona Desmetilases/imunologia , Histona Desmetilases com o Domínio Jumonji/imunologia , Ativação Linfocitária , Células Neoplásicas Circulantes/imunologia , Proteínas Nucleares/imunologia , Proteínas Repressoras/imunologia , Adulto , Antígenos de Neoplasias/imunologia , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Separação Celular , Epitopos de Linfócito T/imunologia , Feminino , Citometria de Fluxo , Antígeno HLA-A2 , Histona Desmetilases/biossíntese , Humanos , Hibridização In Situ , Histona Desmetilases com o Domínio Jumonji/biossíntese , Estadiamento de Neoplasias , Proteínas Nucleares/biossíntese , Peptídeos/imunologia , Proteínas Repressoras/biossíntese
17.
Br J Cancer ; 104(8): 1303-12, 2011 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-21407220

RESUMO

BACKGROUND: Activins and inhibins belong to the TGFß-superfamily, which controls cell proliferation and differentiation in many organs. Activin A, the dimer of inhibin ßA subunit, acts strongly anti-proliferative in hepatocytes. Little is known on the other activin/inhibin subunits in human liver and hepatocellular carcinoma (HCC). METHODS: We studied the expression of the complete inhibin family α, ßA, ßB, ßC, ßE in normal liver, tumour-adjacent and HCC tissue, 12 additional organs and rodent liver. A total of 16 HCC and 10 disease-free livers were analysed. Expression of inhibin subunits was determined by qRT-PCR, normalised to RNA input and by geNorm algorithm, and confirmed by immunohistochemistry. RESULTS: Remarkably, ßA expression was not decreased in HCC. Similarly, ßC and ßE exhibited no major changes. In contrast, inhibin α, barely detectable in normal liver, was strongly increased in tumour-adjacent liver and dramatically enhanced in HCC. ßB was strongly enhanced in some HCC. At variance with human liver, rodent liver showed higher inhibin α and ßC expression, but ßA was somewhat, and ßB dramatically lower. CONCLUSIONS: Upregulation of inhibin α - and possibly of ßB - may shield HCC cells from anti-proliferative effects of activin A. Dramatic variations between humans and rodents may reflect different functions of some inhibins/activins.


Assuntos
Ativinas/genética , Carcinoma Hepatocelular/genética , Inibinas/genética , Neoplasias Hepáticas/genética , Fígado/metabolismo , Roedores/genética , Ativinas/metabolismo , Adulto , Idoso , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Feminino , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Inibinas/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Ratos , Ratos Wistar , Roedores/metabolismo
18.
J Synchrotron Radiat ; 18(Pt 5): 802-10, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21862862

RESUMO

A sapphire backscattering monochromator with 1.1 (1) meV bandwidth for hard X-rays (20-40 keV) is reported. The optical quality of several sapphire crystals has been studied and the best crystal was chosen to work as the monochromator. The small energy bandwidth has been obtained by decreasing the crystal volume impinged upon by the beam and by choosing the crystal part with the best quality. The monochromator was tested at the energies of the nuclear resonances of (121)Sb at 37.13 keV, (125)Te at 35.49 keV, (119)Sn at 23.88 keV, (149)Sm at 22.50 keV and (151)Eu at 21.54 keV. For each energy, specific reflections with sapphire temperatures in the 150-300 K region were chosen. Applications to nuclear inelastic scattering with these isotopes are demonstrated.

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