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1.
Opt Express ; 32(5): 6876-6886, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439383

RESUMO

Frequency conversion based on χ(2) nonlinear optical interactions can be made very efficient in waveguide structures. Fabrication imperfections remain very often a limiting factor. They can induce strong distortions in the spectral shape and lower the efficiency. To overcome these imperfections a post-trimming method based on a cascade of ten micro-heaters on top of the waveguide along the interaction length is demonstrated. As an example, the second harmonic generation in a Ti-indiffused waveguide in periodically poled LiNbO3 is investigated. A tailoring of the spectral characteristics of the phase-matching curves could be successfully demonstrated.

2.
J Pers Med ; 14(2)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38392590

RESUMO

BACKGROUND: Young patients with tongue squamous cell carcinoma (TSCC) mostly lack typical prognostic markers and face a dire prognosis. The aim of this study was to analyze the prognostic relevance of lymphocyte-to-monocyte ratio (LMR) in TSCC patients, with a special emphasis on patients under 45 years. METHODS: This retrospective study included all patients primarily treated for TSCC. The prognostic relevance of LMR was investigated in terms of predicting the overallsurvival (OS) and disease-free survival (DFS). RESULTS: A total of 74 patients were included and the young cohort (<45 years) comprised 27 individuals. The mortality and recurrence rates were 39.2% (n = 29) and 37.8% (n = 28), respectively. OS and DFS were significantly shorter in the low LMR group within the whole cohort. Furthermore, low LMR was associated with worse prognosis, particularly inferior OS (median OS 1.7 vs. 14.6 years, p = 0.0156) and worse DFS (median DFS 0.8 years vs. not reached, p = 0.0405) in the young patient cohort. CONCLUSIONS: Our results reveal that pretreatment LMR might become a prognostic tool for young TSCC patients, especially due to its availability. However, further studies on larger cohorts are necessary to validate our results.

3.
Phys Imaging Radiat Oncol ; 28: 100515, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38111502

RESUMO

Background and purpose: Tools for auto-segmentation in radiotherapy are widely available, but guidelines for clinical implementation are missing. The goal was to develop a workflow for performance evaluation of three commercial auto-segmentation tools to select one candidate for clinical implementation. Materials and Methods: One hundred patients with six treatment sites (brain, head-and-neck, thorax, abdomen, and pelvis) were included. Three sets of AI-based contours for organs-at-risk (OAR) generated by three software tools and manually drawn expert contours were blindly rated for contouring accuracy. The dice similarity coefficient (DSC), the Hausdorff distance, and a dose/volume evaluation based on the recalculation of the original treatment plan were assessed. Statistically significant differences were tested using the Kruskal-Wallis test and the post-hoc Dunn Test with Bonferroni correction. Results: The mean DSC scores compared to expert contours for all OARs combined were 0.80 ± 0.10, 0.75 ± 0.10, and 0.74 ± 0.11 for the three software tools. Physicians' rating identified equivalent or superior performance of some AI-based contours in head (eye, lens, optic nerve, brain, chiasm), thorax (e.g., heart and lungs), and pelvis and abdomen (e.g., kidney, femoral head) compared to manual contours. For some OARs, the AI models provided results requiring only minor corrections. Bowel-bag and stomach were not fit for direct use. During the interdisciplinary discussion, the physicians' rating was considered the most relevant. Conclusion: A comprehensive method for evaluation and clinical implementation of commercially available auto-segmentation software was developed. The in-depth analysis yielded clear instructions for clinical use within the radiotherapy department.

4.
Expert Rev Hematol ; 16(9): 659-670, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37493441

RESUMO

INTRODUCTION: The Vienna Cancer Stem Cell Club (VCSCC) was launched by a group of scientists in Vienna in 2002. AREAS COVERED: Major aims of the VCSCC are to support research on cancer stem cells (CSC) in hematopoietic malignancies and to translate CSC-related markers and targets into clinical application. A primary focus of research in the VCSCC is the leukemic stem cell (LSC). Between 2013 and 2021, members of the VCSCC established a special research program on myeloproliferative neoplasms and since 2008, members of the VCSCC run the Ludwig Boltzmann Institute for Hematology and Oncology. In all these years, the VCSCC provided a robust intellectual platform for translational hematology and LSC research in Vienna. Furthermore, the VCSCC interacts with several national and international study groups and societies in the field. Representatives of the VCSCC also organized a number of international meetings and conferences on neoplastic stem cells, including LSC, in the past 15 years, and contributed to the definition and classification of CSC/LSC and related pre-malignant and malignant conditions. EXPERT OPINION: The VCSCC will continue to advance the field and to develop LSC-detecting and LSC-eradicating concepts through which diagnosis, prognostication, and therapy of blood cancer patients should improve.


Assuntos
Neoplasias Hematológicas , Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Células-Tronco Neoplásicas/patologia , Neoplasias Hematológicas/patologia , Previsões
5.
Opt Express ; 31(14): 22685-22697, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37475373

RESUMO

A reliable, but cost-effective generation of single-photon states is key for practical quantum communication systems. For real-world deployment, waveguide sources offer optimum compatibility with fiber networks and can be embedded in hybrid integrated modules. Here, we present what we believe to be the first chip-size fully integrated fiber-coupled heralded single photon source (HSPS) module based on a hybrid integration of a nonlinear lithium niobate waveguide into a polymer board. Photon pairs at 810 nm (signal) and 1550 nm (idler) are generated via parametric down-conversion pumped at 532 nm in the LiNbO3 waveguide. The pairs are split in the polymer board and routed to separate output ports. The module has a size of (2 × 1) cm2 and is fully fiber-coupled with one pump input fiber and two output fibers. We measure a heralded second-order correlation function of g h(2)=0.05 with a heralding efficiency of η h=3.5% at low pump powers.

6.
Opt Express ; 31(14): 23140-23148, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37475406

RESUMO

Interference between single photons is key for many quantum optics experiments and applications in quantum technologies, such as quantum communication or computation. It is advantageous to operate the systems at telecommunication wavelengths and to integrate the setups for these applications in order to improve stability, compactness and scalability. A new promising material platform for integrated quantum optics is lithium niobate on insulator (LNOI). Here, we realise Hong-Ou-Mandel (HOM) interference between telecom photons from an engineered parametric down-conversion source in an LNOI directional coupler. The coupler has been designed and fabricated in house and provides close to perfect balanced beam splitting. We obtain a raw HOM visibility of (93.5 ± 0.7) %, limited mainly by the source performance and in good agreement with off-chip measurements. This lays the foundation for more sophisticated quantum experiments in LNOI.

7.
Oral Dis ; 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37466114

RESUMO

OBJECTIVE: To map oral health-related standard of care in the context of head and neck cancer (HNC) treatment across the European Union (EU). MATERIALS AND METHODS: Six hundred and ninety centers across the European Union were contacted. The questionnaire contained questions focusing on the team/department structure, HNC treatment planning routines, and assessment and handling of dental treatment needs prior to cancer treatment. RESULTS: Eighty-seven centers across the EU responded. Department structure and number of HNC patients treated per year varied widely and dental professionals are included as part of the team in about 25% of the centers. Standard of care, in terms of dental assessment and preventive dentistry routines, such as recording an orthopantomogram, offering dental treatment, and providing a radiation protection splint and splint for fluoride application, differed significantly among the European regions. Independent of the region, these aspects are positively affected if dental professionals are part of the interdisciplinary treatment team and if dental treatment is offered within the center. CONCLUSION: Dental professionals are still only to a very limited extent included in interdisciplinary treatment planning teams of HNC patients. However, their inclusion and/or offering dental treatment within the same hospital/center appears to improve oral health-related standard of care. CLINICAL RELEVANCE: Inclusion of dental professionals in treatment planning teams of HNC patients appears to improve oral health-related standard of care within HNC treatment.

8.
Opt Lett ; 48(11): 2999-3002, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37262265

RESUMO

This work reports a fully guided setup for single-mode squeezing on integrated titanium-indiffused periodically poled nonlinear resonators. A continuous-wave laser beam is delivered and the squeezed field is collected by single-mode fibers; up to -3.17(9) dB of useful squeezing is available in fibers. To showcase the usefulness of such a fiber-coupled device, we applied the generated squeezed light in a fiber-based phase sensing experiment, showing a quantum enhancement in the signal-to-noise ratio of 0.35 dB. Moreover, our investigation of the effect of photorefraction on the cavity resonance condition suggests that it causes system instabilities at high powers.

9.
Head Neck ; 45(8): 2087-2097, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37345576

RESUMO

OBJECTIVE: Nephrotoxicity is frequent in cisplatin-based chemoradiation of head and neck squamous cell carcinoma (HNSCC). Toxicity outcomes and achieved cisplatin-doses after change of departmental hydration policy are presented. METHODS: We performed a retrospective time-series analysis of HNSCC patients undergoing chemoradiation with conventional hydration (CH) between 01/2017 and 09/2018 versus shorter hydration with mannitol (SHM) between 09/2018 and 08/2019 to compare the rate of acute kidney injury (AKI) and cumulative cisplatin dose. RESULTS: Among 113 HNSCC patients, SHM (n = 35) in comparison to CH (n = 78) correlated with less AKI (54.3% vs. 74.4%; p = 0.034) and higher cisplatin doses (82.9% vs. 61.5% ≥200 mg/m2 ; p = 0.025). AKI ≥grade 2 was lower with SHM (2.9% vs. CH: 22.8%; p = 0.01). AKI occurred more frequently in females (92.6% vs. males: 60.5%, p = 0.002). Females received lower cumulative cisplatin doses (51.9% vs. males: 73.3%; p = 0.037). CONCLUSIONS: We observed less AKI and higher cumulative chemotherapy doses with SHM. Female patients were at higher risk of AKI.


Assuntos
Injúria Renal Aguda , Antineoplásicos , Neoplasias de Cabeça e Pescoço , Masculino , Humanos , Feminino , Cisplatino/efeitos adversos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Manitol/uso terapêutico , Antineoplásicos/efeitos adversos , Estudos Retrospectivos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/tratamento farmacológico , Rim
10.
Am J Hematol ; 98(5): 770-783, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36814396

RESUMO

Myeloproliferative neoplasms (MPN) are characterized by uncontrolled expansion of myeloid cells, disease-related mutations in certain driver-genes including JAK2, CALR, and MPL, and a substantial risk to progress to secondary acute myeloid leukemia (sAML). Although behaving as stem cell neoplasms, little is known about disease-initiating stem cells in MPN. We established the phenotype of putative CD34+ /CD38- stem cells and CD34+ /CD38+ progenitor cells in MPN. A total of 111 patients with MPN suffering from polycythemia vera, essential thrombocythemia, or primary myelofibrosis (PMF) were examined. In almost all patients tested, CD34+ /CD38- stem cells expressed CD33, CD44, CD47, CD52, CD97, CD99, CD105, CD117, CD123, CD133, CD184, CD243, and CD274 (PD-L1). In patients with PMF, MPN stem cells often expressed CD25 and sometimes also CD26 in an aberrant manner. MPN stem cells did not exhibit substantial amounts of CD90, CD273 (PD-L2), CD279 (PD-1), CD366 (TIM-3), CD371 (CLL-1), or IL-1RAP. The phenotype of CD34+ /CD38- stem cells did not change profoundly during progression to sAML. The disease-initiating capacity of putative MPN stem cells was confirmed in NSGS mice. Whereas CD34+ /CD38- MPN cells engrafted in NSGS mice, no substantial engraftment was produced by CD34+ /CD38+ or CD34- cells. The JAK2-targeting drug fedratinib and the BRD4 degrader dBET6 induced apoptosis and suppressed proliferation in MPN stem cells. Together, MPN stem cells display a unique phenotype, including cytokine receptors, immune checkpoint molecules, and other clinically relevant target antigens. Phenotypic characterization of neoplastic stem cells in MPN and sAML should facilitate their enrichment and the development of stem cell-eradicating (curative) therapies.


Assuntos
Leucemia Mieloide Aguda , Transtornos Mieloproliferativos , Policitemia Vera , Animais , Camundongos , Calreticulina/genética , Janus Quinase 2/genética , Mutação , Transtornos Mieloproliferativos/genética , Células-Tronco Neoplásicas , Proteínas Nucleares/genética , Fenótipo , Policitemia Vera/genética , Fatores de Transcrição/genética , Humanos
11.
J Allergy Clin Immunol ; 151(1): 202-211, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35953001

RESUMO

BACKGROUND: Mast cells (MC) and basophils are effector cells of allergic reactions and display a number of activation-linked cell surface antigens. Of these antigens, however, only a few are functionally relevant and specifically expressed in these cells. OBJECTIVE: We sought to identify MC- and basophil-specific surface molecules and to study their cellular distribution and regulation during cytokine-induced and IgE-dependent activation. METHODS: Multicolor flow cytometry was performed to recognize surface antigens and to determine changes in antigen expression upon activation. RESULTS: We identified Siglec-6 (CD327) as a differentially regulated surface antigen on human MC and basophils. In the bone marrow, Siglec-6 was expressed abundantly on MC in patients with mastocytosis and in reactive states, but it was not detected on other myeloid cells, with the exception of basophils and monocytes. In healthy individuals, allergic patients, and patients with chronic myeloid leukemia (CML), Siglec-6 was identified on CD203c+ blood basophils, a subset of CD19+ B lymphocytes, and few CD14+ monocytes, but not on other blood leukocytes. CML basophils expressed higher levels of Siglec-6 than normal basophils. IL-3 promoted Siglec-6 expression on normal and CML basophils, and stem cell factor increased the expression of Siglec-6 on tissue MC. Unexpectedly, IgE-dependent activation resulted in downregulation of Siglec-6 in IL-3-primed basophils, whereas in MC, IgE-dependent activation augmented stem cell factor-induced upregulation of Siglec-6. CONCLUSIONS: Siglec-6 is a dynamically regulated marker of MC and basophils. Activated MC and basophils exhibit unique Siglec-6 responses, including cytokine-dependent upregulation and unique, cell-specific, responses to IgE-receptor cross-linking.


Assuntos
Basófilos , Mastócitos , Humanos , Antígenos CD , Doença Crônica , Imunoglobulina E , Interleucina-3/metabolismo , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico , Fator de Células-Tronco/metabolismo
12.
Strahlenther Onkol ; 199(6): 536-543, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35953611

RESUMO

PURPOSE: To describe a local radio-oncological treatment for patients with prostate cancer that metastasized to either the lymph nodes or distant regions. METHODS AND MATERIALS: We included 133 patients with prostate cancer that displayed either distant metastases (DM) or lymph node metastases alone (NM) and were treated between 2004 and 2019. All patients underwent computed tomography and a bone scan or 18F- or prostate-specific membrane antigen-targeted positron emission tomography. Patients received local external beam radiation therapy to the prostate to achieve local control (60-81.4 Gy to the prostate, and 45-50.4 Gy to pelvic lymph nodes), with either the 3D conformal (4-field box) or volumetric modulated arc therapy technique. A urologist prescribed additional therapy. RESULTS: We included 51 patients with DM and 82 patients with NM. The mean follow-up was 42 months for all patients. The groups were similar in T stage, initial prostate-specific antigen, histology, androgen deprivation therapy, age, treatment techniques, and prescribed doses, but different in lymph node inclusion and follow-up times. In the NM and DM groups, the 5­year biochemical recurrence-free rates were 52% and 24%, respectively (p < 0.0001); the 5­year disease-specific survival rates were 92% and 61%, respectively (p = 0.001); and the 5­year OS rates were 77% and 48%, respectively (p = 0.01). The groups had similar acute and late gastrointestinal and genitourinary side effects, except that late genitourinary side effects occurred significantly more frequently in the NM group (p = 0.01). CONCLUSIONS: DM was associated with significantly worse outcomes than NM. The long-term survival of patients with metastatic prostate cancer was low.


Assuntos
Neoplasias da Próstata , Radioterapia de Intensidade Modulada , Masculino , Humanos , Neoplasias da Próstata/patologia , Antagonistas de Androgênios/uso terapêutico , Radioterapia de Intensidade Modulada/métodos , Antígeno Prostático Específico , Sistema Urogenital/patologia
13.
Cancers (Basel) ; 14(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36139596

RESUMO

Aim: The aim of this study was to assess the effects of including somatostatin receptor agonist (SSTR) PET imaging in meningioma radiotherapy planning by means of changes in inter-observer variability (IOV). Further, the possibility of using threshold-based delineation approaches for semiautomatic tumor volume definition was assessed. Patients and Methods: Sixteen patients with meningioma undergoing fractionated radiotherapy were delineated by five radiation oncologists. IOV was calculated by comparing each delineation to a consensus delineation, based on the simultaneous truth and performance level estimation (STAPLE) algorithm. The consensus delineation was used to adapt a threshold-based delineation, based on a maximization of the mean Dice coefficient. To test the threshold-based approach, seven patients with SSTR-positive meningioma were additionally evaluated as a validation group. Results: The average Dice coefficients for delineations based on MRI alone was 0.84 ± 0.12. For delineation based on MRI + PET, a significantly higher dice coefficient of 0.87 ± 0.08 was found (p < 0.001). The Hausdorff distance decreased from 10.96 ± 11.98 mm to 8.83 ± 12.21 mm (p < 0.001) when adding PET for the lesion delineation. The best threshold value for a threshold-based delineation was found to be 14.0% of the SUVmax, with an average Dice coefficient of 0.50 ± 0.19 compared to the consensus delineation. In the validation cohort, a Dice coefficient of 0.56 ± 0.29 and a Hausdorff coefficient of 27.15 ± 21.54 mm were found for the threshold-based approach. Conclusions: SSTR-PET added to standard imaging with CT and MRI reduces the IOV in radiotherapy planning for patients with meningioma. When using a threshold-based approach for PET-based delineation of meningioma, a relatively low threshold of 14.0% of the SUVmax was found to provide the best agreement with a consensus delineation.

14.
Biophys J ; 121(20): 3850-3861, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36101505

RESUMO

Vimentin is a highly charged intermediate filament protein that inherently forms extended dimeric coiled coils, which serve as the basic building blocks of intermediate filaments. Under low ionic strength conditions, vimentin filaments dissociate into uniform tetrameric complexes of two anti-parallel-oriented, half-staggered coiled-coil dimers. By addition of salt, vimentin tetramers spontaneously reassemble into filaments in a time-dependent process: 1) lateral assembly of tetramers into unit-length filaments, 2) longitudinal annealing of unit-length filaments, and 3) longitudinal assembly of filaments coupled with subsequent radial compaction. To independently determine the lateral and longitudinal assembly kinetics, we measure with a stopped-flow instrument the static light scattering signal at two different wavelengths (405 and 594 nm) with a temporal resolution of 3 ms and analyze the signals based on Rayleigh-Gans theory. This theory considers that the intensity of the scattered light depends not only on the molecular weight of the scattering object but also on its shape. This shape dependence is more pronounced at shorter wavelengths, allowing us to decompose the scattered light signal into its components arising from lateral and longitudinal filament assembly. We demonstrate that both the lateral and longitudinal filament assembly kinetics increase with salt concentration.


Assuntos
Citoesqueleto , Filamentos Intermediários , Filamentos Intermediários/metabolismo , Vimentina , Cinética , Citoesqueleto/metabolismo , Concentração Osmolar
15.
Elife ; 112022 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-36053000

RESUMO

Numerous cell functions are accompanied by phenotypic changes in viscoelastic properties, and measuring them can help elucidate higher level cellular functions in health and disease. We present a high-throughput, simple and low-cost microfluidic method for quantitatively measuring the elastic (storage) and viscous (loss) modulus of individual cells. Cells are suspended in a high-viscosity fluid and are pumped with high pressure through a 5.8 cm long and 200 µm wide microfluidic channel. The fluid shear stress induces large, ear ellipsoidal cell deformations. In addition, the flow profile in the channel causes the cells to rotate in a tank-treading manner. From the cell deformation and tank treading frequency, we extract the frequency-dependent viscoelastic cell properties based on a theoretical framework developed by R. Roscoe [1] that describes the deformation of a viscoelastic sphere in a viscous fluid under steady laminar flow. We confirm the accuracy of the method using atomic force microscopy-calibrated polyacrylamide beads and cells. Our measurements demonstrate that suspended cells exhibit power-law, soft glassy rheological behavior that is cell-cycle-dependent and mediated by the physical interplay between the actin filament and intermediate filament networks.


Cells in the human body are viscoelastic: they have some of the properties of an elastic solid, like rubber, as well as properties of a viscous fluid, like oil. To carry out mechanical tasks ­ such as, migrating through tissues to heal a wound or to fight inflammation ­ cells need the right balance of viscosity and elasticity. Measuring these two properties can therefore help researchers to understand important cell tasks and how they are impacted by disease. However, quantifying these viscous and elastic properties is tricky, as both depend on the time-scale they are measured: when pressed slowly, cells appear soft and liquid, but they turn hard and thick when rapidly pressed. Here, Gerum et al. have developed a new system for measuring the viscosity and elasticity of individual cells that is fast, simple, and inexpensive. In this new method, cells are suspended in a specialized solution with a consistency similar to machine oil which is then pushed with high pressure through channels less than half a millimeter wide. The resulting flow of fluid shears the cells, causing them to elongate and rotate, which is captured using a fast camera that takes 500 images per second. Gerum et al. then used artificial intelligence to extract each cell's shape and rotation speed from these images, and calculated their viscosity and elasticity based on existing theories of how viscoelastic objects behave in fluids. Gerum et al. also investigated how the elasticity and viscosity of cells changed with higher rotation frequencies, which corresponds to shorter time-scales. This revealed that while higher frequencies made the cells appear more viscous and elastic, the ratio between these two properties remained the same. This means that researchers can compare results obtained from different experimental techniques, even if the measurements were carried out at completely different frequencies or time-scales. The method developed by Gerum et al. provides a fast an inexpensive way for analyzing the viscosity and elasticity of cells. It could also be a useful tool for screening the effects of drugs, or as a diagnostic tool to detect diseases that affect the mechanical properties of cells.


Assuntos
Elasticidade , Citometria de Fluxo , Reologia/métodos , Estresse Mecânico , Viscosidade
16.
Biomedicines ; 10(8)2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-36009513

RESUMO

Neuronal activity is the key modulator of nearly every aspect of behavior, affecting cognition, learning, and memory as well as motion. Hence, disturbances of the transmission of synaptic signals are the main cause of many neurological disorders. Lesions to nervous tissues are associated with phenotypic changes mediated by astrocytes becoming reactive. Reactive astrocytes form the basis of astrogliosis and glial scar formation. Astrocyte reactivity is often targeted to inhibit axon dystrophy and thus promote neuronal regeneration. Here, we aim to understand the impact of gravitational loading induced by hypergravity to potentially modify key features of astrocyte reactivity. We exposed primary murine astrocytes as a model system closely resembling the in vivo reactivity phenotype on custom-built centrifuges for cultivation as well as for live-cell imaging under hypergravity conditions in a physiological range (2g and 10g). We revealed spreading rates, migration velocities, and stellation to be diminished under 2g hypergravity. In contrast, proliferation and apoptosis rates were not affected. In particular, hypergravity attenuated reactivity induction. We observed cytoskeletal remodeling of actin filaments and microtubules under hypergravity. Hence, the reorganization of these key elements of cell structure demonstrates that fundamental mechanisms on shape and mobility of astrocytes are affected due to altered gravity conditions. In future experiments, potential target molecules for pharmacological interventions that attenuate astrocytic reactivity will be investigated. The ultimate goal is to enhance neuronal regeneration for novel therapeutic approaches.

17.
J Clin Med ; 11(10)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35628813

RESUMO

Objective: To evaluate the impact of radiotherapy (RT) on dysphagia and long-term swallowing outcome in patients with stage III and IV head and neck squamous cell carcinomas (HNSCCs). Material and Methods: Between 2005 and 2008, 189 patients with HNSCCs underwent primary or adjuvant RT in a curative setting. Long-term swallowing outcome was evaluated in 50 patients. Among them, 26 were further eligible for prospective analysis of long-term swallowing and dysphagia outcome. Medical charts were retrospectively reviewed regarding pre- and post-treatment dysphagia (3 months after last irradiation setting) as well as persisting long-term dysphagia (2019−2021). Results: Pre-treatment dysphagia was observed in 24 (48%) of 50 patients, particularly in oropharyngeal or hypopharyngeal stage III−IV tumors (OR 9.3; p = 0.003). Conversely, 46 patients (92%) complained about post-treatment dysphagic symptoms, which were more commonly seen in patients with positive neck nodes (OR 10.5; p = 0.037). The post-treatment dysphagia rate dropped from 92% to 24% (p < 0.001) during surveillance, which was significantly linked to xerostomia (OR 5.77; p = 0.019), dysgeusia (OR 9.9; p = 0.036) and free flap reconstruction (OR 6.1; p = 0.022). Conclusion: Pretreatment dysphagia is common in advanced stage HNSCCs and almost all patients complain about dysphagia at the end of RT. Importantly, applied RT protocols did not affect long-term dysphagia, which improves significantly in the majority of patients over time. Meeting Information: Preliminary results have been presented at the 65th Annual Meeting of the Austrian Society of Otorhinolaryngology, 22−26 September 2021, Austria.

18.
Radiol Oncol ; 56(3): 365-370, 2022 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-35502906

RESUMO

BACKGROUND: The aim of the study was to evaluate the development of treatment of primary high-risk prostate cancer in regards to biochemical no evidence of disease (bNED), acute and late gastrointestinal (GI) and genitourinary (GU) side effects. PATIENTS AND METHODS: Primary high-risk prostate cancer patients treated between 1994 and 2016 were included. Applied doses ranged from 60 to 80 Gy, with a dose of 1.8 or 2 Gy per fraction. Techniques were either 3D conformal or intensity modulated radiotherapy and volumetric intensity modulated arc therapy. RESULTS: 142 patients were treated with doses up to 70 Gy (median dose 66 Gy; 66 Gy group), 282 with doses between 70 and 76 Gy (median dose 74 Gy; 74 Gy group), and 141 with doses >76 Gy (median dose 78 Gy; 78 Gy group). The median follow-up was 48 months. The bNED rates were 50% after 5 years and 44% after 9 years in the 66 Gy group; 65% and 54%, respectively, in the 74 Gy group; and 83% and 66%, respectively, in the 78 Gy group (p = 0.03 vs. 74 Gy and p < 0.0001 vs. 66 Gy). We found a higher rate of acute GI side effects in the 78 Gy group compared to the other groups, but not in maximum acute GU side effects and late maximum GI and GU effects. CONCLUSIONS: High-risk prostate cancer patients treated with doses of 78 Gy had significantly better bNED rates. Compared to the historical 66 Gy group, 50% more patients achieved bNED after a follow-up of 9 years.


Assuntos
Neoplasias da Próstata , Radioterapia Conformacional , Radioterapia de Intensidade Modulada , Humanos , Masculino , Neoplasias da Próstata/radioterapia , Dosagem Radioterapêutica , Radioterapia Conformacional/efeitos adversos , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos
19.
Biophys J ; 121(6): 1094-1104, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35124070

RESUMO

Intermediate filament (IF) proteins assemble into highly flexible filaments that organize into complex cytoplasmic networks: keratins in all types of epithelia, vimentin in endothelia, and desmin in muscle. Since IF elongation proceeds via end-to-end annealing of unit-length filaments and successively of progressively growing filaments, it is important to know how their remarkable flexibility, i.e., their persistence length lp, influences the assembly kinetics. In fact, their lp ranges between 0.3 µm (keratin K8/K18) and 1.0 µm (vimentin and desmin), and thus is orders of magnitude lower than that of microtubules and F-actin. Here, we present a unique mathematical model, which implements the semiflexible nature of the three IF types based on published semiflexible polymers theories and depends on a single free parameter k0. Calibrating this model to filament mean length dynamics of the three proteins, we demonstrate that the persistence length is indeed essential to accurately describe their assembly kinetics. Furthermore, we reveal that the difference in flexibility alone does not explain the significantly faster assembly rate of keratin filaments compared with that of vimentin. Likewise, desmin assembles approximately six times faster than vimentin, even though both their filaments exhibit the same lp value. These data strongly indicate that differences in their individual amino acid sequences significantly impact the assembly rates. Nevertheless, using a single k0 value for each of these three key representatives of the IF protein family, our advanced model does accurately describe the length distribution and mean length dynamics and provides effective filament assembly rates. It thus provides a tool for future investigations on the impact of posttranslational modifications or amino acid changes of IF proteins on assembly kinetics. This is an important issue, as the discovery of mutations in IF genes causing severe human disease, particularly for desmin and keratins, is steadily increasing.


Assuntos
Proteínas de Filamentos Intermediários , Filamentos Intermediários , Desmina/química , Humanos , Proteínas de Filamentos Intermediários/metabolismo , Filamentos Intermediários/metabolismo , Queratinas/química , Queratinas/metabolismo , Modelos Teóricos , Vimentina/química
20.
FEBS J ; 289(10): 2755-2770, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33825342

RESUMO

Desmin is the primary intermediate filament (IF) of cardiac, skeletal, and smooth muscle. By linking the contractile myofibrils to the sarcolemma and cellular organelles, desmin IF contributes to muscle structural and cellular integrity, force transmission, and mitochondrial homeostasis. Mutations in desmin cause myofibril misalignment, mitochondrial dysfunction, and impaired mechanical integrity leading to cardiac and skeletal myopathies in humans, often characterized by the accumulation of protein aggregates. Recent evidence indicates that desmin filaments also regulate proteostasis and cell size. In skeletal muscle, changes in desmin filament dynamics can facilitate catabolic events as an adaptive response to a changing environment. In addition, post-translational modifications of desmin and its misfolding in the heart have emerged as key determinants of homeostasis and disease. In this review, we provide an overview of the structural and cellular roles of desmin and propose new models for its novel functions in preserving the homeostasis of striated muscles.


Assuntos
Desmina , Músculo Esquelético , Miofibrilas , Desmina/genética , Desmina/fisiologia , Homeostase , Humanos , Músculo Esquelético/fisiologia , Doenças Musculares/genética , Doenças Musculares/metabolismo , Miofibrilas/fisiologia
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