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1.
Unfallchirurgie (Heidelb) ; 127(4): 263-272, 2024 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-38276974

RESUMO

The frequency of osteoporotic vertebral fractures in the clinical routine is increasing due to the demographic change. They are the most frequent fractures associated with osteoporosis and affect an especially morbid and vulnerable group of patients. These fractures often occur after minor trauma or spontaneously. Pain is the predominant symptom, whereas mechanical stability is mostly sufficient, in comparison to vertebral fractures after high-energy trauma, and is not a predominant indication for surgery. These fractures can be described using the classification for fractures associated with osteoporosis and the corresponding treatment recommendations are guided by them. Besides the specific treatment of osteoporotic vertebral fractures, a holistic treatment of patients taking pre-existing comorbidities into consideration is decisive. A mobilization as quickly as possible and treatment of the underlying osteoporosis are important to prevent further fractures.


Assuntos
Fraturas por Compressão , Cifoplastia , Osteoporose , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Humanos , Cifoplastia/efeitos adversos , Fraturas por Compressão/complicações , Fraturas por Osteoporose/epidemiologia , Fraturas da Coluna Vertebral/epidemiologia , Osteoporose/complicações , Vértebras Lombares/diagnóstico por imagem
2.
ArXiv ; 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37064527

RESUMO

Intravoxel Incoherent Motion (IVIM) is a non-contrast magnetic resonance imaging diffusion-based scan that uses a multitude of b-values to measure various speeds of molecular perfusion and diffusion, sidestepping inaccuracy of arterial input functions or bolus kinetics in quantitative imaging. We test a new method of IVIM quantification and compare our values to reference standard neutron capture microspheres across normocapnia, CO2 induced hypercapnia, and middle cerebral artery occlusion in a controlled animal model. Perfusion quantification in ml/100g/min compared to microsphere perfusion uses the 3D gaussian probability distribution and defined water transport time as when 50% of the molecules remain in the tissue of interest. Perfusion, water transport time, and infarct volume was compared to reference standards. Simulations were studied to suppress non-specific cerebrospinal fluid (CSF). Linear regression analysis of quantitative perfusion returned correlation (slope = .55, intercept = 52.5, $R^2$= .64). Linear regression for water transport time asymmetry in infarcted tissue was excellent (slope = .59, intercept = .3, $R^2$ = .93). Strong linear agreement also was found for infarct volume (slope = 1.01, $R^2$= .79). Simulation of CSF suppression via inversion recovery returned blood signal reduced by 82% from combined T1 and T2 effects. Intra-physiologic state comparison of perfusion shows potential partial volume effects which require further study especially in disease states. The accuracy and sensitivity of IVIM provides evidence that observed signal changes reflect cytotoxic edema and tissue perfusion. Partial volume contamination of CSF may be better removed during post-processing rather than with inversion recovery to avoid artificial loss of blood signal.

7.
Pharmazie ; 77(3): 90-94, 2022 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-35459435

RESUMO

The present investigation involved the synthesis of a number of novel benzylidene hydrazides as candidate cytotoxic agents. The preparation of these compounds from terephthalic acid and isophthalic acid proceeded satisfactorily. However, the reaction of phthalic acid hydrazide with various aryl aldehydes was unsuccessful in general. Some of the unexpected products were identified. The shapes and also the distances between the centers of the aryl rings designated B and C of three representative compounds 1b, 2b and 3b were determined. The compounds designated 1a-e, 2a-e and 3b were screened against human HCT116 and HT29 colon cancer cells as well as human CRL1790 non-malignant colon cells which revealed the tumor-selective toxicity displayed by these compounds.


Assuntos
Antineoplásicos , Neoplasias , Antibacterianos , Antineoplásicos/farmacologia , Humanos , Hidrazinas/farmacologia , Ácidos Ftálicos
8.
Unfallchirurg ; 125(5): 351-360, 2022 May.
Artigo em Alemão | MEDLINE | ID: mdl-35175406

RESUMO

The technique of 3D printing offers a high potential for further optimization of spinal surgery. This new technology has been published for different areas in the field of spinal surgery, e.g. in preoperative planning, intraoperative use as well as to create patient-specific implants. For example, it has been demonstrated that preoperative 3­dimensional visualization of spinal deformities is helpful in planning procedures. Moreover, insertion of pedicle screws seems to be more accurate when using individualized templates to guide the drill compared to freehand techniques. This review summarizes the current literature dealing with 3D printing in spinal surgery with special consideration of the current applications, the limitations and the future potential.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Cirurgia Assistida por Computador , Humanos , Procedimentos Neurocirúrgicos , Impressão Tridimensional , Fusão Vertebral/métodos
9.
Br J Dermatol ; 186(3): 553-563, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34726260

RESUMO

BACKGROUND: Epithelioid haemangioma (EH) arising from the skin is a benign vascular tumour with marked inflammatory cell infiltration, which exhibits a high tendency to persist and frequently recurs after resection. So far, the underlying pathogenesis is largely elusive. OBJECTIVES: To identify genetic alterations by next-generation sequencing and/or droplet digital polymerase chain reaction (ddPCR) in cutaneous EH. METHODS: DNA and RNA from an EH lesion of an index patient were subjected to whole-genome and RNA sequencing. Multiplex PCR-based panel sequencing of genomic DNA isolated from archival formalin-fixed paraffin-embedded tissue of 18 patients with cutaneous EH was performed. ddPCR was used to confirm mutations. RESULTS: We identified somatic mutations in genes of the mitogen-activated protein kinase (MAPK) pathway (MAP2K1 and KRAS) in cutaneous EH biopsies. By ddPCR we could confirm the recurrent presence of activating, low-frequency mutations affecting MAP2K1. In total, nine out of 18 patients analysed showed activating MAPK pathway mutations, which were mutually exclusive. Comparative analysis of tissue areas enriched for lymphatic infiltrate or aberrant endothelial cells, respectively, revealed an association of these mutations with the presence of endothelial cells. CONCLUSIONS: Taken together, our data suggest that EH shows somatic mutations in genes of the MAPK pathway which might contribute to the formation of this benign tumour.


Assuntos
Hemangioma , Neoplasias Cutâneas , DNA , Células Endoteliais , Hemangioma/genética , Humanos , Proteínas Quinases Ativadas por Mitógeno/genética , Reação em Cadeia da Polimerase Multiplex , Mutação/genética , Recidiva Local de Neoplasia , Neoplasias Cutâneas/genética
10.
Nanoscale ; 13(21): 9808-9815, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34031687

RESUMO

The photophysics of an inorganic/organic hybrid system was studied by time-resolved optical spectroscopy, focusing on the goal of increasing the two-photon efficiency of photoresponsive systems. The hybrid system consists of CdS/ZnS core/shell quantum dots (QDs) as energy donor and coumarin derivatives as energy acceptor molecules. The spectral overlap of QD emission and coumarin 343 absorption promotes a Förster resonance energy tranfer (FRET) mechanism leading to a FRET efficiency up to nearly 90%. Additionally, time-correlated single photon counting showed a faster fluorescence decay while acceptor molecules were attached to the QD surface. Femtosecond transient absorption measurements demonstrated an ultrafast FRET reaction. Importantly, FRET was observed also after two-photon excitation of the QDs indicating that the chosen QDs can act as two-photon antennas.

11.
Phys Rev Lett ; 125(21): 216402, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33274982

RESUMO

Trigonal tellurium, a small-gap semiconductor with pronounced magneto-electric and magneto-optical responses, is among the simplest realizations of a chiral crystal. We have studied by spin- and angle-resolved photoelectron spectroscopy its unconventional electronic structure and unique spin texture. We identify Kramers-Weyl, composite, and accordionlike Weyl fermions, so far only predicted by theory, and show that the spin polarization is parallel to the wave vector along the lines in k space connecting high-symmetry points. Our results clarify the symmetries that enforce such spin texture in a chiral crystal, thus bringing new insight in the formation of a spin vectorial field more complex than the previously proposed hedgehog configuration. Our findings thus pave the way to a classification scheme for these exotic spin textures and their search in chiral crystals.

12.
J Psychiatr Res ; 131: 160-168, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32977236

RESUMO

Maternal ante- and postnatal anxiety have been associated with children's socio-emotional development. Moreover, maternal anxiety has been studied as both a contributing factor and consequence of preterm birth, and children born preterm are more likely to develop behavioural problems compared to term-born controls. This study investigated the association between maternal anxiety measured soon after birth and mental health in 215 ex-preterm children, born at <33 weeks, who participated in the Evaluation of Preterm Imaging Study. Children were followed-up at a median age of 4.6 years (range 4.2-6.6), and received behavioural and cognitive evaluation. Maternal trait anxiety was assessed with the Spielberger State-Trait Anxiety Index at term corrected age. Primary outcome measures were children's Strengths and Difficulties Questionnaire (SDQ) and Social Responsiveness Scale 2 (SRS-2) scores, indicative of generalised psychopathology and autism symptomatology, respectively. IQ was assessed with the Wechsler Preschool and Primary Scales of Intelligence. The final sample, after excluding participants with missing data and multiple pregnancy (n = 75), consisted of 140 children (51.4% male). Results showed that increased maternal trait anxiety at term corrected age was associated with children's higher SDQ scores (ß = 0.25, 95% CI 0.09-0.41, p = 0.003, f2 = 0.08) and SRS-2 scores (ß = 0.15, 95% CI 0.02-0.28, p = 0.03, f2 = 0.04). Our findings indicate that children born preterm whose mothers are more anxious in the early postnatal period may show poorer mental health outcomes at pre-school age. Further research is needed to investigate preventative measures that can be offered to high-risk premature babies and their families.


Assuntos
Nascimento Prematuro , Ansiedade/epidemiologia , Criança , Pré-Escolar , Emoções , Feminino , Humanos , Lactente , Recém-Nascido , Inteligência , Masculino , Mães , Gravidez , Nascimento Prematuro/epidemiologia
13.
Phys Rev Lett ; 125(7): 076401, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32857568

RESUMO

In nodal-line semimetals, linearly dispersing states form Dirac loops in the reciprocal space with a high degree of electron-hole symmetry and a reduced density of states near the Fermi level. The result is reduced electronic screening and enhanced correlations between Dirac quasiparticles. Here we investigate the electronic structure of ZrSiSe, by combining time- and angle-resolved photoelectron spectroscopy with ab initio density functional theory (DFT) complemented by an extended Hubbard model (DFT+U+V) and by time-dependent DFT+U+V. We show that electronic correlations are reduced on an ultrashort timescale by optical excitation of high-energy electrons-hole pairs, which transiently screen the Coulomb interaction. Our findings demonstrate an all-optical method for engineering the band structure of a quantum material.

15.
Phys Rev Lett ; 124(20): 206402, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32501104

RESUMO

Lead-halide perovskite (LHP) semiconductors are emergent optoelectronic materials with outstanding transport properties which are not yet fully understood. We find signatures of large polaron formation in the electronic structure of the inorganic LHP CsPbBr_{3} by means of angle-resolved photoelectron spectroscopy. The experimental valence band dispersion shows a hole effective mass of 0.26±0.02 m_{e}, 50% heavier than the bare mass m_{0}=0.17 m_{e} predicted by density functional theory. Calculations of the electron-phonon coupling indicate that phonon dressing of the carriers mainly occurs via distortions of the Pb-Br bond with a Fröhlich coupling parameter α=1.81. A good agreement with our experimental data is obtained within the Feynman polaron model, validating a viable theoretical method to predict the carrier effective mass of LHPs ab initio.

16.
Commun Chem ; 3(1): 88, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-36703468

RESUMO

Photopolymerization is a key enabling technology offering spatial and temporal control to allow for future functional materials to be made to meet societal needs. However, gaining access to robust experimental techniques to describe the evolution of nanoscale morphology in photo-initiated polymeric systems has proven so far to be a challenging task. Here, we show that these physical transformations can be monitored and quantified at the nanoscale in situ and in real-time. It is demonstrated that the initial structural features of the liquid precursors significantly affect the final morphology and the physical properties of the resulting solid via the occurrence of local heterogeneities in the molecular mobility during the curing transformation. We have made visible how local physical arrestings in the liquid, associated with both cross-linking and vitrification, determine the length scale of the local heterogeneities forming upon curing, found to be in the 10-200 nm range.

17.
Mult Scler Relat Disord ; 34: 63-65, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31229736

RESUMO

BACKGROUND: Fingolimod is the first approved oral disease-modifying treatment for relapsing-remitting multiple sclerosis. Fingolimod targets lymphocytes, exerting a modulator effect on cell-surface sphingosine-1-phosphate receptors and thus blocking lymphocytes egression from secondary lymphoid organs. Recent reports describe fingolimod cessation being followed by severe or pseudo-tumoral relapse, but it usually does not happen on continuous long-term treatment. CASE PRESENTATION: Here we present the case of a patient on continuous long-term fingolimod treatment who presented with fulminant atypical multifocal relapse involving over 30 new and active lesions. CONCLUSION: This case is unique since this fulminant multifocal relapse occurred in a patient with grade 3 lymphopenia and irreproachable adherence. This observation should be known as a possible side effect of fingolimod treatment.


Assuntos
Cloridrato de Fingolimode/uso terapêutico , Imunossupressores/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/terapia , Adulto , Feminino , Humanos , Linfopenia/etiologia , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Esclerose Múltipla Recidivante-Remitente/patologia , Natalizumab/uso terapêutico , Cooperação e Adesão ao Tratamento
18.
Forensic Sci Int ; 297: 177-183, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30802646

RESUMO

The present paper aims to assess the risk of rib fractures caused by any rigid less-lethal kinetic energy projectiles. To that end, a coupled experimental and numerical approach is proposed to relate ballistic experiments with the risk of blunt trauma. A polymer gel block is employed as ballistic testing medium to interpret ballistic impacts through the measurement of the dynamic gel wall displacement. Moreover, a biofidelic 50th percentile human torso finite element model created in the code Hypermesh (Altair HyperWorks ©) is used to replicate experiments and real world accidents. Then, the probability curve of rib fractures is a function of the viscous criterion and derives from a study on human cadaver mid-sternum available in the literature. Twelve impact conditions of rigid projectiles are applied to a SEBS gel block and are replicated on the human torso model mid-sternum. A statistical analysis is performed by virtue of a Spearman's correlation matrix in order to identify relations between experimental measurements and the viscous criterion evaluated numerically. The determination of both statistical significances and correlation coefficients results in several strong correlations between experimental measurements and the viscous criterion evaluated numerically. These relations imply the establishment of transfer functions between experimental metrics on the gel block (the maximum gel wall displacement and a gel wall displacement - rate of displacement based metric) and the probability of rib fractures. Finally, these correlations constitute a primary and an up-and-coming predicting tool for the risk of rib fractures.


Assuntos
Balística Forense , Cinética , Modelos Biológicos , Fraturas das Costelas , Ferimentos não Penetrantes , Análise de Elementos Finitos , Géis , Humanos , Modelos Logísticos , Polímeros
19.
Int J Cardiovasc Imaging ; 34(11): 1779-1785, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29948639

RESUMO

Aim of the present study is to compare magnetic resonance imaging (MRI) and positron emission tomography (PET) parameters in the follow up of chronic periaortitis (CP), with a focus on changes in the apparent diffusion coefficient (ADC) and standardized uptake values (SUV). 127 patients with CP were treated in our urology between 2007 and 2017. We identified 14 patients with parallel abdominal MRI and PET-CT examinations before therapy and in the follow up resulting in a total of 56 examinations. Relative contrast uptake and diffusion-weighted MRI parameters were compared to SUV in the corresponding PET-CT examinationsand laboratory infection markers. All examined MRI and PET-CT parameters showed significant changes between basis and follow-up examinations. Median ADC values increased significantly (p < 0.001) in the follow up. SUVmax and the other MR parameter (contrast uptake, DWI-signal) declined significantly. We observed a strong negative correlation between ADC and SUVmax (rho: - 0.61; p < 0.001). In addition, we found an inverse correlation of ADC with the inflammation markers ESR (rho: - 0.64; p < 0.001) and CRP (rho: - 0.54; p = 0.001). MRI and PET-CT showed comparable results in the individual follow up of CP and compared to laboratory inflammation markers. Our data support MRI as first imaging modality due to absent radiation and the necessity of repetitive follow-up examinations in patients with CP.


Assuntos
Imagem de Difusão por Ressonância Magnética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fibrose Retroperitoneal/diagnóstico por imagem , Idoso , Biomarcadores/sangue , Sedimentação Sanguínea , Proteína C-Reativa/metabolismo , Doença Crônica , Feminino , Glucocorticoides/administração & dosagem , Humanos , Mediadores da Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fibrose Retroperitoneal/sangue , Fibrose Retroperitoneal/tratamento farmacológico , Estudos Retrospectivos , Resultado do Tratamento
20.
Eur J Neurol ; 25(5): 762-767, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29431876

RESUMO

BACKGROUND AND PURPOSE: In 2011, fingolimod was approved in Switzerland for the treatment of relapsing-remitting multiple sclerosis (RRMS). The aim of the present study was to assess the effectiveness and retention of fingolimod in a real-life Swiss setting, in which patients can receive fingolimod as both first- and second-line treatment for RRMS. METHODS: This cross-sectional, observational study with retrospective data collection was performed at 19 sites that comprised both hospitals and office-based physicians across Switzerland. Sites were asked to document eligible patients in consecutive chronological order to avoid selection bias. Demographic and clinical data from 274 consenting adult patients with RRMS who had received treatment with fingolimod were analyzed. RESULTS: Mean treatment duration with fingolimod was 32 months. Under fingolimod, 77.7% of patients remained free from relapses and 90.3% did not experience disability progression. The proportion of patients who were free from any clinical disease activity, i.e. without relapses and disability progression, was 72.1%. A total of 28.5% of patients had been RRMS treatment-naïve prior to fingolimod therapy. High long-term treatment retention rates ranging between 95.7% at 24 months and 87.8% at 36 months were observed. CONCLUSION: In this Swiss cohort of naïve and pre-treated subjects with RRMS, the majority of patients under fingolimod treatment showed freedom from relapses and disability progression. In addition, treatment retention rate over 2 and 3 years was high, irrespective of previous treatment.


Assuntos
Cloridrato de Fingolimode/uso terapêutico , Imunossupressores/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Adulto , Idoso , Estudos Transversais , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Suíça , Resultado do Tratamento , Adulto Jovem
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