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1.
Mol Psychiatry ; 28(9): 3829-3841, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37783788

RESUMO

Psilocybin (a classic serotonergic psychedelic drug) has received appraisal for use in psychedelic-assisted therapy of several psychiatric disorders. A less explored topic concerns the use of repeated low doses of psychedelics, at a dose that is well below the psychedelic dose used in psychedelic-assisted therapy and often referred to as microdosing. Psilocybin microdose users frequently report increases in mental health, yet such reports are often highly biased and vulnerable to placebo effects. Here we establish and validate a psilocybin microdose-like regimen in rats with repeated low doses of psilocybin administration at a dose derived from occupancy at rat brain 5-HT2A receptors in vivo. The rats tolerated the repeated low doses of psilocybin well and did not manifest signs of anhedonia, anxiety, or altered locomotor activity. There were no deficits in pre-pulse inhibition of the startle reflex, nor did the treatment downregulate or desensitize the 5-HT2A receptors. However, the repeated low doses of psilocybin imparted resilience against the stress of multiple subcutaneous injections, and reduced the frequency of self-grooming, a proxy for human compulsive actions, while also increasing 5-HT7 receptor expression and synaptic density in the paraventricular nucleus of the thalamus. These results establish a well-validated regimen for further experiments probing the effects of repeated low doses of psilocybin. Results further substantiate anecdotal reports of the benefits of psilocybin microdosing as a therapeutic intervention, while pointing to a possible physiological mechanism.


Assuntos
Alucinógenos , Resiliência Psicológica , Humanos , Animais , Ratos , Psilocibina/farmacologia , Psilocibina/uso terapêutico , Alucinógenos/farmacologia , Alucinógenos/uso terapêutico , Núcleos da Linha Média do Tálamo , Serotonina , Comportamento Compulsivo
2.
Strahlenther Onkol ; 199(8): 739-748, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37285037

RESUMO

PURPOSE: Auxiliary devices such as immobilization systems should be considered in synthetic CT (sCT)-based treatment planning (TP) for MRI-only brain radiotherapy (RT). A method for auxiliary device definition in the sCT is introduced, and its dosimetric impact on the sCT-based TP is addressed. METHODS: T1-VIBE DIXON was acquired in an RT setup. Ten datasets were retrospectively used for sCT generation. Silicone markers were used to determine the auxiliary devices' relative position. An auxiliary structure template (AST) was created in the TP system and placed manually on the MRI. Various RT mask characteristics were simulated in the sCT and investigated by recalculating the CT-based clinical plan on the sCT. The influence of auxiliary devices was investigated by creating static fields aimed at artificial planning target volumes (PTVs) in the CT and recalculated in the sCT. The dose covering 50% of the PTV (D50) deviation percentage between CT-based/recalculated plan (∆D50[%]) was evaluated. RESULTS: Defining an optimal RT mask yielded a ∆D50[%] of 0.2 ± 1.03% for the PTV and between -1.6 ± 3.4% and 1.1 ± 2.0% for OARs. Evaluating each static field, the largest ∆D50[%] was delivered by AST positioning inaccuracy (max: 3.5 ± 2.4%), followed by the RT table (max: 3.6 ± 1.2%) and the RT mask (max: 3.0 ± 0.8% [anterior], 1.6 ± 0.4% [rest]). No correlation between ∆D50[%] and beam depth was found for the sum of opposing beams, except for (45°â€¯+ 315°). CONCLUSION: This study evaluated the integration of auxiliary devices and their dosimetric influence on sCT-based TP. The AST can be easily integrated into the sCT-based TP. Further, we found that the dosimetric impact was within an acceptable range for an MRI-only workflow.


Assuntos
Imageamento por Ressonância Magnética , Planejamento da Radioterapia Assistida por Computador , Humanos , Estudos Retrospectivos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem
3.
Eur J Oper Res ; 291(1): 379-393, 2021 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-33041471

RESUMO

In this work, we investigate the challenges public-sector organizations face when seeking to leverage prescriptive analytics and provide insights into the public value such data-driven tools and methods can provide. Using the strategic triangle of value, legitimacy, and operational capacity as a starting point, we derive a framework to assess public-sector prescriptive analytics initiatives, along with six guiding questions that structure the assessment process. We present a case study applying prescriptive analytics to the placement of charge points in urban areas, a critical challenge many municipalities are currently facing in the transition towards electric mobility. Reflecting on the analytics application as well as its development and implementation process through the guiding questions, we derive key lessons for public-sector organizations seeking to apply prescriptive analytics.

4.
Stroke ; 50(2): 298-304, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30661490

RESUMO

Background and Purpose- We sought to explore the effect of genetic imbalance on functional outcome after ischemic stroke (IS). Methods- Copy number variation was identified in high-density single-nucleotide polymorphism microarray data of IS patients from the CADISP (Cervical Artery Dissection and Ischemic Stroke Patients) and SiGN (Stroke Genetics Network)/GISCOME (Genetics of Ischaemic Stroke Functional Outcome) networks. Genetic imbalance, defined as total number of protein-coding genes affected by copy number variations in an individual, was compared between patients with favorable (modified Rankin Scale score of 0-2) and unfavorable (modified Rankin Scale score of ≥3) outcome after 3 months. Subgroup analyses were confined to patients with imbalance affecting ohnologs-a class of dose-sensitive genes, or to those with imbalance not affecting ohnologs. The association of imbalance with outcome was analyzed by logistic regression analysis, adjusted for age, sex, stroke subtype, stroke severity, and ancestry. Results- The study sample comprised 816 CADISP patients (age 44.2±10.3 years) and 2498 SiGN/GISCOME patients (age 67.7±14.2 years). Outcome was unfavorable in 122 CADISP and 889 SiGN/GISCOME patients. Multivariate logistic regression analysis revealed that increased genetic imbalance was associated with less favorable outcome in both samples (CADISP: P=0.0007; odds ratio=0.89; 95% CI, 0.82-0.95 and SiGN/GISCOME: P=0.0036; odds ratio=0.94; 95% CI, 0.91-0.98). The association was independent of age, sex, stroke severity on admission, stroke subtype, and ancestry. On subgroup analysis, imbalance affecting ohnologs was associated with outcome (CADISP: odds ratio=0.88; 95% CI, 0.80-0.95 and SiGN/GISCOME: odds ratio=0.93; 95% CI, 0.89-0.98) whereas imbalance without ohnologs lacked such an association. Conclusions- Increased genetic imbalance was associated with poorer functional outcome after IS in both study populations. Subgroup analysis revealed that this association was driven by presence of ohnologs in the respective copy number variations, suggesting a causal role of the deleterious effects of genetic imbalance.


Assuntos
Isquemia Encefálica/genética , Dosagem de Genes , Adulto , Idoso , Isquemia Encefálica/reabilitação , Cromossomos Humanos/genética , Seguimentos , Duplicação Gênica , Genótipo , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Recuperação de Função Fisiológica , Índice de Gravidade de Doença
5.
Curr Genomics ; 18(2): 206-213, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28367076

RESUMO

BACKGROUND: Genetic and environmental risk factors are assumed to contribute to the susceptibility to cervical artery dissection (CeAD). To explore the role of genetic imbalance in the etiology of CeAD, copy number variants (CNVs) were identified in high-density microarrays samples from the multicenter CADISP (Cervical Artery Dissection and Ischemic Stroke Patients) study and from control subjects from the CADISP study and the German PopGen biobank. Microarray data from 833 CeAD patients and 2040 control subjects (565 subjects with ischemic stroke due to causes different from CeAD and 1475 disease-free individuals) were analyzed. Rare genic CNVs were equally frequent in CeAD-patients (16.4%; n=137) and in control subjects (17.0%; n=346) but differed with respect to their genetic content. Compared to control subjects, CNVs from CeAD patients were enriched for genes associated with muscle organ development and cell differentiation, which suggests a possible association with arterial development. CNVs affecting cardiovascular system development were more common in CeAD patients than in control subjects (p=0.003; odds ratio (OR) =2.5; 95% confidence interval (95% CI) =1.4-4.5) and more common in patients with a familial history of CeAD than in those with sporadic CeAD (p=0.036; OR=11.2; 95% CI=1.2-107). CONCLUSION: The findings suggest that rare genetic imbalance affecting cardiovascular system development may contribute to the risk of CeAD. Validation of these findings in independent study populations is warranted.

6.
Hum Mol Genet ; 23(10): 2580-92, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24399447

RESUMO

Defects of the oxidative phosphorylation system, in particular of cytochrome-c oxidase (COX, respiratory chain complex IV), are common causes of Leigh syndrome (LS), which is a rare neurodegenerative disorder with severe progressive neurological symptoms that usually present during infancy or early childhood. The COX-deficient form of LS is commonly caused by mutations in genes encoding COX assembly factors, e.g. SURF1, SCO1, SCO2 or COX10. However, other mutations affecting genes that encode proteins not directly involved in COX assembly can also cause LS. The leucine-rich pentatricopeptide repeat containing protein (LRPPRC) regulates mRNA stability, polyadenylation and coordinates mitochondrial translation. In humans, mutations in Lrpprc cause the French Canadian type of LS. Despite the finding that LRPPRC deficiency affects the stability of most mitochondrial mRNAs, its pathophysiological effect has mainly been attributed to COX deficiency. Surprisingly, we show here that the impaired mitochondrial respiration and reduced ATP production observed in Lrpprc conditional knockout mouse hearts is caused by an ATP synthase deficiency. Furthermore, the appearance of inactive subassembled ATP synthase complexes causes hyperpolarization and increases mitochondrial reactive oxygen species production. Our findings shed important new light on the bioenergetic consequences of the loss of LRPPRC in cardiac mitochondria.


Assuntos
Mitocôndrias Cardíacas/enzimologia , ATPases Mitocondriais Próton-Translocadoras/deficiência , Proteínas de Neoplasias/genética , Trifosfato de Adenosina/biossíntese , Animais , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético , Humanos , Doença de Leigh/genética , Potencial da Membrana Mitocondrial , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias Cardíacas/patologia , ATPases Mitocondriais Próton-Translocadoras/genética , Fosforilação Oxidativa , Consumo de Oxigênio , Multimerização Proteica , Espécies Reativas de Oxigênio/metabolismo
7.
Plant Cell Environ ; 39(6): 1366-80, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26670204

RESUMO

Sucrose accumulation in leaves in response to various abiotic stresses suggests a specific role of this disaccharide for stress tolerance and adaptation. The high-affinity transporter StSUT1 undergoes substrate-induced endocytosis presenting the question as to whether altered sucrose accumulation in leaves in response to stresses is also related to enhanced endocytosis or altered activity of the sucrose transporter. StSUT1 is known to interact with several stress-inducible proteins; here we investigated whether one of the interacting candidates, StPDI1, affects its subcellular localization in response to stress: StPDI1 expression is induced by ER-stress and salt. Both proteins, StSUT1 and StPDI1, were found in the detergent resistant membrane (DRM) fraction, and this might affect internalization. Knockdown of StPDI1 expression severely affects abiotic stress tolerance of transgenic potato plants. Analysis of these plants does not reveal modified subcellular localization or endocytosis of StSUT1, but rather a disturbed redox homeostasis, reduced detoxification of reactive oxygen species and effects on primary metabolism. Parallel observations with other StSUT1-interacting proteins are discussed. The redox status in leaves seems to be linked to the sugar status in response to various stress stimuli and to play a role in stress tolerance.


Assuntos
Homeostase , Proteínas de Transporte de Monossacarídeos/fisiologia , Oxirredução , Proteínas de Plantas/fisiologia , Isomerases de Dissulfetos de Proteínas/fisiologia , Sacarose/metabolismo , Clonagem Molecular , Técnicas de Silenciamento de Genes , Homeostase/fisiologia , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase em Tempo Real , Solanum tuberosum/embriologia , Solanum tuberosum/fisiologia , Estresse Fisiológico/fisiologia
8.
Proc Natl Acad Sci U S A ; 109(42): 16906-10, 2012 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-23035244

RESUMO

The proteins MDM2 and MDM4 are key negative regulators of the tumor suppressor protein p53, which are frequently upregulated in cancer cells. They inhibit the transactivation activity of p53 by binding separately or in concert to its transactivation domain. MDM2 is also a ubiquitin ligase that leads to the degradation of p53. Accordingly, MDM2 and MDM4 are important targets for drugs to inhibit their binding to p53. We found from in silico screening and confirmed by experiment that lithocholic acid (LCA) binds to the p53 binding sites of both MDM2 and MDM4 with a fivefold preference for MDM4. LCA is an endogenous steroidal bile acid, variously reported to have both carcinogenic and apoptotic activities. The comparison of LCA effects on apoptosis in HCT116 p53(+/+) vs. p53(-/-) cells shows a predominantly p53-mediated induction of caspase-3/7. The dissociation constants are in the µM region, but only modest inhibition of binding of MDM2 and MDM4 is required to negate their upregulation because they have to compete with transcriptional coactivator p300 for binding to p53. Binding was weakened by structural changes in LCA, and so it may be a natural ligand of MDM2 and MDM4, raising the possibility that MDM proteins may be sensors for specific steroids.


Assuntos
Regulação Neoplásica da Expressão Gênica/fisiologia , Ácido Litocólico/farmacologia , Proteínas Nucleares/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 7/metabolismo , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Cromatografia de Afinidade , Escherichia coli , Polarização de Fluorescência , Humanos , Espectroscopia de Ressonância Magnética , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Ultracentrifugação
9.
Magn Reson Med ; 72(6): 1680-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24436227

RESUMO

PURPOSE: Cartesian turbo spin-echo (TSE) and radial TSE images are usually reconstructed by assembling data containing different contrast information into a single k-space. This approach results in mixed contrast contributions in the images, which may reduce their diagnostic value. The goal of this work is to improve the image contrast from radial TSE acquisitions by reducing the contribution of signals with undesired contrast information. METHODS: Radial TSE acquisitions allow the reconstruction of multiple images with different T2 contrasts using the k-space weighted image contrast (KWIC) filter. In this work, the image contrast is improved by reducing the band-width of the KWIC filter. Data for the reconstruction of a single image are selected from within a small temporal range around the desired echo time. The resulting dataset is undersampled and, therefore, an iterative parallel imaging algorithm is applied to remove aliasing artifacts. RESULTS: Radial TSE images of the human brain reconstructed with the proposed method show an improved contrast when compared with Cartesian TSE images or radial TSE images with conventional KWIC reconstructions. CONCLUSION: The proposed method provides multi-contrast images from radial TSE data with contrasts similar to multi spin-echo images. Contaminations from unwanted contrast weightings are strongly reduced.


Assuntos
Algoritmos , Artefatos , Encéfalo/anatomia & histologia , Imagem Ecoplanar/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Técnica de Subtração , Humanos , Movimento (Física) , Reprodutibilidade dos Testes , Tamanho da Amostra , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Marcadores de Spin
10.
Proc Natl Acad Sci U S A ; 108(20): 8251-6, 2011 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-21525412

RESUMO

Lys120 in the DNA-binding domain (DBD) of p53 becomes acetylated in response to DNA damage. But, the role and effects of acetylation are obscure. We prepared p53 specifically acetylated at Lys120, AcK120p53, by in vivo incorporation of acetylated lysine to study biophysical and structural consequences of acetylation that may shed light on its biological role. Acetylation had no affect on the overall crystal structure of the DBD at 1.9-Å resolution, but significantly altered the effects of salt concentration on specificity of DNA binding. p53 binds DNA randomly in vitro at effective physiological salt concentration and does not bind specifically to DNA or distinguish among its different response elements until higher salt concentrations. But, on acetylation, AcK120p53 exhibited specific DNA binding and discriminated among response elements at effective physiological salt concentration. AcK120p53 and p53 had the highest affinity to the same DNA sequence, although acetylation reduced the importance of the consensus C and G at positions 4 and 7, respectively. Mass spectrometry of p53 and AcK120p53 DBDs bound to DNA showed they preferentially segregated into complexes that were either DNA(p53DBD)(4) or DNA(AcK120DBD)(4), indicating that the different DBDs prefer different quaternary structures. These results are consistent with electron microscopy observations that p53 binds to nonspecific DNA in different, relaxed, quaternary states from those bound to specific sequences. Evidence is accumulating that p53 can be sequestered by random DNA, and target search requires acetylation of Lys120 and/or interaction with other factors to impose specificity of binding via modulating changes in quaternary structure.


Assuntos
DNA/metabolismo , Methanosarcina barkeri/metabolismo , Engenharia de Proteínas , Proteína Supressora de Tumor p53/química , Acetilação , Sítios de Ligação , Cristalografia por Raios X , Dano ao DNA , Escherichia coli , Lisina/química , Lisina-tRNA Ligase/metabolismo , Methanosarcina barkeri/química , Modelos Moleculares , Estrutura Terciária de Proteína , Sais/química
11.
Proc Natl Acad Sci U S A ; 108(2): 557-62, 2011 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-21178074

RESUMO

The multidomain homotetrameric tumor suppressor p53 has two modes of binding dsDNA that are thought to be responsible for scanning and recognizing specific response elements (REs). The C termini bind nonspecifically to dsDNA. The four DNA-binding domains (DBDs) bind REs that have two symmetric 10 base-pair sequences. p53 bound to a 20-bp RE has the DBDs enveloping the DNA, which is in the center of the molecule surrounded by linker sequences to the tetramerization domain (Tet). We investigated by electron microscopy structures of p53 bound to DNA sequences consisting of a 20-bp RE with either 12 or 20 bp nonspecific extensions on either end. We found a variety of structures that give clues to recognition and scanning mechanisms. The 44- and 60-bp sequences gave rise to three and four classes of structures, respectively. One was similar to the known 20-bp structure, but the DBDs in the other classes were loosely arranged and incompatible with specific DNA recognition. Some of the complexes had density consistent with the C termini extending from Tet to the DNA, adjacent to the DBDs. Single-molecule fluorescence resonance energy transfer experiments detected the approach of the C termini towards the DBDs on addition of DNA. The structural data are consistent with p53 sliding along DNA via its C termini and the DNA-binding domains hopping on and off during searches for REs. The loose structures and posttranslational modifications account for the affinity of nonspecific DNA for p53 and point to a mechanism of enhancement of specificity by its binding to effector proteins.


Assuntos
DNA/química , Microscopia Eletrônica/métodos , Proteína Supressora de Tumor p53/química , Alanina/química , Cistina/química , Transferência Ressonante de Energia de Fluorescência , Genes p53 , Humanos , Mutação , Conformação de Ácido Nucleico , Ligação Proteica , Conformação Proteica , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína
12.
Biotechnol J ; 19(3): e2300348, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38472091

RESUMO

The development and manufacture of biopharmaceuticals are subject to strict regulations that specify the required minimum quality of the products. A key measure to meet these quality requirements is the integration of a sterile filtration step into the commercial manufacturing process. Whereas common procedures for most biologics exist, this is challenging for lentiviral vector (LVV) production for ex vivo gene therapy. LVVs nominal size is more than half the pore size (0.2 µm) of filters used for sterile filtration. Hence, highly concentrated virus solutions are prone to filter clogging if aggregation of viruses occurs or impurities attach to the viruses. Several filters were screened aiming to identify those which allow filtering highly concentrated stocks of LVVs of up to 1E + 9 transducing units mL-1 , which corresponds to 4.5E + 12 particles mL-1 . In addition, the effect of endonuclease treatment upstream of the purification process on filter performance was studied. In summary, three suitable filters were identified in a small-scale study (<15 mL) with virus yields >80% and the process was successfully scaled-up to a final scale of 100 mL LVV stock solution.


Assuntos
Lentivirus , Vírus , Lentivirus/genética , Vírus/genética , Filtração/métodos , Terapia Genética
13.
Biotechnol J ; 19(5): e2400090, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38719592

RESUMO

The production of lentiviral vectors (LVs) pseudotyped with the vesicular stomatitis virus envelope glycoprotein (VSV-G) is limited by the associated cytotoxicity of the envelope and by the production methods used, such as transient transfection of adherent cell lines. In this study, we established stable suspension producer cell lines for scalable and serum-free LV production derived from two stable, inducible packaging cell lines, named GPRG and GPRTG. The established polyclonal producer cell lines produce self-inactivating (SIN) LVs carrying a WAS-T2A-GFP construct at an average infectious titer of up to 4.64 × 107 TU mL-1 in a semi-perfusion process in a shake flask and can be generated in less than two months. The derived monoclonal cell lines are functionally stable in continuous culture and produce an average infectious titer of up to 9.38 × 107 TU mL-1 in a semi-perfusion shake flask process. The producer clones are able to maintain a productivity of >1 × 107 TU mL-1 day-1 for up to 29 consecutive days in a non-optimized 5 L stirred-tank bioreactor perfusion process, representing a major milestone in the field of LV manufacturing. As the producer cell lines are based on an inducible Tet-off expression system, the established process allows LV production in the absence of inducers such as antibiotics. The purified LVs efficiently transduce human CD34+ cells, reducing the LV quantities required for gene and cell therapy applications.


Assuntos
Reatores Biológicos , Vetores Genéticos , Lentivirus , Lentivirus/genética , Humanos , Vetores Genéticos/genética , Meios de Cultura Livres de Soro , Linhagem Celular , Técnicas de Cultura de Células/métodos , Cultura de Vírus/métodos , Células HEK293 , Transfecção/métodos
14.
Z Med Phys ; 2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37666699

RESUMO

Before introducing new treatment techniques, an investigation of hazards due to unintentional radiation exposures is a reasonable activity for proactively increasing patient safety. As dedicated software is scarce, we developed a tool for risk assessment to design a quality management program based on best practice methods, i.e., process mapping, failure modes and effects analysis and fault tree analysis. Implemented as a web database application, a single dataset was used to describe the treatment process and its failure modes. The design of the system and dataset allowed failure modes to be represented both visually as fault trees and in a tabular form. Following the commissioning of the software for our department, previously conducted risk assessments were migrated to the new system after being fully re-assessed which revealed a shift in risk priorities. Furthermore, a weighting factor was investigated to bring risk levels of the migrated assessments into perspective. The compensation did not affect high priorities but did re-prioritize in the midrange of the ranking. We conclude that the tool is suitable to conduct multiple risk assessments and concomitantly keep track of the overall quality management activities.

15.
BMC Neurol ; 12: 102, 2012 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-23007013

RESUMO

BACKGROUND: Patients in neurologic in-patient rehabilitation are at risk of cardio- and cerebrovascular events. Microalbuminuria (MAU) is frequent and an important risk predictor but has not been validated in in-patient rehabilitation. We therefore aimed to examine MAU as an indicator of risk and predictor of vascular events in a prospective study. METHODS: The INSIGHT (INvestigation of patients with ischemic Stroke In neuroloGic reHabiliTation) registry is the first to provide large scale data on 1,167 patients with acute stroke (< 3 months) that survived the initial phase of high risk and were undergoing neurologic in-patient rehabilitation. MAU was determined by dipstick-testing and correlated to baseline clinical variables (stroke-origin, functional impairment, co-morbidity, ankle-brachial-index, intima-media-thickeness) as well as vascular events after one year of follow-up. Comparisons were made with the χ2 or Mann-Whitney-U Test. Relative risks (RR) with 95% confidence intervals (CI) were estimated using log-binominal models. To evaluate the association between MAU and new vascular events as well as mortality, we calculated hazard ratios (HR) using Cox proportional hazard regression. RESULTS: A substantial proportion of patients was MAU positive at baseline (33.1%). Upon univariate analysis these patients were about 4 years older (69 vs. 65 years; p < 0.0001), had a slightly higher body mass index (27.8 vs. 27.1 kg/m2; p = 0.03) and increased waist circumference (79.5 vs. 50.4% for women [p < 0.0001] and 46.8 vs. 43.2% for men [p = 0.04]) and twice as often had diabetes mellitus (41.8 vs. 20.1%; p < 0.0001). Patients with MAU had a similar NIH stroke scale score (median 3 vs. 3; p = 0.379) but had lower values on the Barthel Index (median 75 vs. 90; p < 0.001). They had higher rates of atrial fibrillation (RR 1.38; 95% CI 1.09-1.75), coronary artery disease (RR 1.54; 95% CI 1.18-2.00), heart failure (RR 1.70; 95% CI 1.10-2.60) symptomatic peripheral artery disease (RR 2.30; 95% CI 1.40-3.80) and atherosclerotic stroke etiology (53.7 vs. 35.4%; p < 0.0001). MAU was associated with an increased intima-media-thickness, decreased ankle-brachial-index and polyvascular disease (RR 1.56; 95%CI 1.31-1.99). The event rate after a median follow-up of 13 months was 6.7% for fatal or nonfatal stroke, 4.7% for death, and 10.9% for combined vascular events (stroke, MI, vascular death). The presence of MAU was predictive for vascular events during the following year (HR for total mortality 2.2; 95% CI 1.3-3.7; HR for cardiovascular events 2.3; 95% 1.2 - 4.4). CONCLUSIONS: INSIGHT demonstrated a significant association between MAU and polyvascular disease and further supports previous findings that MAU predicts cardio-/cerebrovascular events in patients recovering from ischemic stroke. This biomarker may also be used in patients during neurologic in-patient rehabilitation, opening a window of opportunity for early intervention in this patient group at increased risk for recurrent events.


Assuntos
Albuminúria/epidemiologia , Transtornos Cerebrovasculares/epidemiologia , Transtornos Cerebrovasculares/prevenção & controle , Sistema de Registros , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/epidemiologia , Distribuição por Idade , Idoso , Comorbidade , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Medição de Risco , Fatores de Risco , Distribuição por Sexo , Resultado do Tratamento
16.
Z Med Phys ; 2022 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-36539322

RESUMO

PURPOSE: A new insert for a commercially available end-to-end test phantom was designed and in-house manufactured by 3D printing. Subsequently, the insert was tested for different stereotactic radiation therapy workflows (SRS, SBRT, FSRT, and Multimet) also in comparison to the original insert. MATERIAL AND METHODS: Workflows contained imaging (MR, CT), treatment planning, positioning, and irradiation. Positioning accuracy was evaluated for non-coplanar x-ray, kV- and MV-CBCT systems, as well as surface guided radiation therapy. Dosimetric accuracy of the irradiation was measured with an ionization chamber at four different linear accelerators including dynamic tumor tracking for SBRT. RESULTS: CT parameters of the insert were within the specification. For MR images, the new insert allowed quantitative analysis of the MR distortion. Positioning accuracy of the phantom with the new insert using the imaging systems of the different linacs was < 1 mm/degree also for MV-CBCT and a non-coplanar imaging system which caused > 3 mm deviation with the original insert. Deviation of point dose values was <3% for SRS, FSRT, and SBRT for both inserts. For the Multimet plans deviations exceeded 10% because the ionization chamber was not positioned in each metastasis, but in the center of phantom and treatment plan. CONCLUSION: The in-house manufactured insert performed well in all steps of four stereotactic treatment end-to-end tests. Advantages over the commercially available alternative were seen for quantitative analysis of deformation correction in MR images, applicability for non-coplanar x-ray imaging, and dynamic tumor tracking.

17.
Z Med Phys ; 31(4): 388-393, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33622568

RESUMO

The purpose of this work was to develop a treatment plan verification routine for a linear accelerator dedicated to SBRT treatments with gimbal based dynamic tumor tracking using three commercially available phantoms. The accelerator system has two special features: It operates with a rotation of the ring shaped gantry instead of a couch rotation and target motion can be compensated for via a gimbal system (dynamic tumor tracking, DTT). DTT plans were each measured with the three different phantoms. Afterwards the measured dose distribution was compared with the calculated dose distribution via global Gamma Index analysis (3mm / 3%, threshold: 10%). The global gamma pass rates were on average (93.5±7.2) % for ArcCHECK, (98.0±2.6) % for OCTAVIUS® 4D and (98.4±4.2) % for MatriXX Evolution. All three systems could be used for quality assurance with ring rotations and DTT, however, each with limitations.


Assuntos
Neoplasias , Radioterapia de Intensidade Modulada , Humanos , Aceleradores de Partículas , Imagens de Fantasmas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
18.
Front Neurol ; 12: 663830, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34135851

RESUMO

Cervical artery dissection (CeAD) occurring in the context of sports is a matter of concern for CeAD patients. They seek advice on the role of sports in CeAD and on the safety of resuming sports after CeAD. The scarcity of studies and guidelines addressing these issues poses a challenge. We aimed at summarizing the current knowledge about CeAD and sports in order to provide an informed, comprehensive opinion for counseling CeAD patients. We took into account pathophysiological considerations, observations of cases reports, series, and registries, and conclusions by analogy from aortic dissection or inherited connective tissue syndromes. In summary, practicing active sports as the cause of CeAD seems uncommon. It seems recommendable to refrain from any kind of sports activities for at least 1 month, which can be extended in case of an unfavorable clinical or neurovascular course. We recommend starting with sport activities at low intensity-preferably with types of endurance sports-and to gradually increase the pace in an individually tailored manner, taking into circumstances of the occurrences of the CeAD in the individual patient (particularly in relation to sports), the meaning of sports activities for the individual well-being, the presence or absence of comorbidities and of neurological sequela, neurovascular findings, and whether there are signs of an underlying connective tissue alteration. Major limitations and several forms of bias are acknowledged. Still, in the absence of any better data, the summarized observations and considerations might help clinicians in advising and counseling patients with CeAD in clinical practice.

19.
Neurology ; 94(2): e170-e180, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31757869

RESUMO

OBJECTIVE: To assess the impact of dissected artery occlusion (DAO) on functional outcome and complications in patients with cervical artery dissection (CeAD). METHODS: We analyzed combined individual patient data from 3 multicenter cohorts of consecutive patients with CeAD (the Cervical Artery Dissection and Ischemic Stroke Patients [CADISP]-Plus consortium dataset). Patients with data on DAO and functional outcome were included. We compared patients with DAO to those without DAO. Primary outcome was favorable functional outcome (i.e., modified Rankin Scale [mRS] score 0-1) measured 3-6 months from baseline. Secondary outcomes included delayed cerebral ischemia, major hemorrhage, recurrent CeAD, and death. We performed univariate and multivariable binary logistic regression analyses and calculated odds ratios (OR) with 95% confidence intervals (CI), with adjustment for potential confounders. RESULTS: Of 2,148 patients (median age 45 years [interquartile range (IQR) 38-52], 43.6% women), 728 (33.9%) had DAO. Patients with DAO more frequently presented with cerebral ischemia (84.6% vs 58.5%, p < 0.001). Patients with DAO were less likely to have favorable outcome when compared to patients without DAO (mRS 0-1: 59.6% vs 80.1%, p unadjusted < 0.001). After adjustment for age, sex, and initial stroke severity, DAO was independently associated with less favorable outcome (mRS 0-1: OR 0.65, CI 0.50-0.84, p = 0.001). Delayed cerebral ischemia occurred more frequently in patients with DAO than in patients without DAO (4.5% vs 2.9%, p = 0.059). CONCLUSION: DAO independently predicts less favorable functional outcome in patients with CeAD. Further research on vessel patency, collateral status and effects of revascularization therapies particularly in patients with DAO is warranted.


Assuntos
Dissecção Aórtica/patologia , Doenças Arteriais Cerebrais/patologia , Transtornos Cerebrovasculares/patologia , Recuperação de Função Fisiológica , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
BMC Genomics ; 10: 628, 2009 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-20030809

RESUMO

BACKGROUND: Transcription factors activate their target genes by binding to specific response elements. Many transcription factor families evolved from a common ancestor by gene duplication and subsequent divergent evolution. Members of the p53 family, which play key roles in cell-cycle control and development, share conserved DNA binding and oligomerisation domains but exhibit distinct functions. In this study, the molecular basis of the functional divergence of related transcription factors was investigated. RESULTS: We characterised the DNA-binding specificity and oligomerisation properties of human p53, p63 and p73, as well as p53 from other organisms using novel biophysical approaches. All p53 family members bound DNA cooperatively as tetramers with high affinity. Despite structural differences in the oligomerisation domain, the dissociation constants of the tetramers was in the low nanomolar range for all family members, indicating that the strength of tetramerisation was evolutionarily conserved. However, small differences in the oligomerisation properties were observed, which may play a regulatory role. Intriguingly, the DNA-binding specificity of p53 family members was highly conserved even for evolutionarily distant species. Additionally, DNA recognition was only weakly affected by CpG methylation. Prediction of p53/p63/p73 binding sites in the genome showed almost complete overlap between the different homologs. CONCLUSION: Diversity of biological function of p53 family members is not reflected in differences in sequence-specific DNA binding. Hence, additional specificity factors must exist, which allowed the acquisition of novel functions during evolution while preserving original roles.


Assuntos
Sequência Conservada , Proteínas de Ligação a DNA/genética , Genes p53 , Fatores de Transcrição/genética , Sítios de Ligação , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Genoma Humano , Humanos , Família Multigênica , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Multimerização Proteica , Análise de Sequência de DNA , Especificidade por Substrato , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Proteína Tumoral p73 , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
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