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1.
Eur Radiol ; 33(11): 7807-7817, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37212845

RESUMO

OBJECTIVES: Non-contrast computed tomography (NCCT) markers are robust predictors of parenchymal hematoma expansion in intracerebral hemorrhage (ICH). We investigated whether NCCT features can also identify ICH patients at risk of intraventricular hemorrhage (IVH) growth. METHODS: Patients with acute spontaneous ICH admitted at four tertiary centers in Germany and Italy were retrospectively included from January 2017 to June 2020. NCCT markers were rated by two investigators for heterogeneous density, hypodensity, black hole sign, swirl sign, blend sign, fluid level, island sign, satellite sign, and irregular shape. ICH and IVH volumes were semi-manually segmented. IVH growth was defined as IVH expansion > 1 mL (eIVH) or any delayed IVH (dIVH) on follow-up imaging. Predictors of eIVH and dIVH were explored with multivariable logistic regression. Hypothesized moderators and mediators were independently assessed in PROCESS macro models. RESULTS: A total of 731 patients were included, of whom 185 (25.31%) suffered from IVH growth, 130 (17.78%) had eIVH, and 55 (7.52%) had dIVH. Irregular shape was significantly associated with IVH growth (OR 1.68; 95%CI [1.16-2.44]; p = 0.006). In the subgroup analysis stratified by the IVH growth type, hypodensities were significantly associated with eIVH (OR 2.06; 95%CI [1.48-2.64]; p = 0.015), whereas irregular shape (OR 2.72; 95%CI [1.91-3.53]; p = 0.016) in dIVH. The association between NCCT markers and IVH growth was not mediated by parenchymal hematoma expansion. CONCLUSIONS: NCCT features identified ICH patients at a high risk of IVH growth. Our findings suggest the possibility to stratify the risk of IVH growth with baseline NCCT and might inform ongoing and future studies. CLINICAL RELEVANCE STATEMENT: Non-contrast CT features identified ICH patients at a high risk of intraventricular hemorrhage growth with subtype-specific differences. Our findings may assist in the risk stratification of intraventricular hemorrhage growth with baseline CT and might inform ongoing and future clinical studies. KEY POINTS: • NCCT features identified ICH patients at a high risk of IVH growth with subtype-specific differences. • The effect of NCCT features was not moderated by time and location or indirectly mediated by hematoma expansion. • Our findings may assist in the risk stratification of IVH growth with baseline NCCT and might inform ongoing and future studies.


Assuntos
Hemorragia Cerebral , Tomografia Computadorizada por Raios X , Humanos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Hemorragia Cerebral/diagnóstico por imagem , Hematoma/diagnóstico por imagem , Alemanha/epidemiologia
2.
EMBO Rep ; 20(7): e48541, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31267713

RESUMO

Experiments in space and on free-fall platforms have yielded important insights into plant's reaction to low gravity with potential applications for space research and exploration.


Assuntos
Fenômenos Fisiológicos Vegetais , Ausência de Peso , Produção Agrícola/métodos , Exobiologia/métodos , Simulação de Ambiente Espacial/métodos
3.
Stroke ; 50(1): 83-87, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30580701

RESUMO

Background and Purpose- Arterial ischemic stroke (AIS) in childhood is a severe disease with potentially lifelong restrictions. Apart from cardiac or prothrombotic embolism, arteriopathy has been identified as a major cause and significant target of secondary stroke prevention. The Childhood Arterial Ischemic Stroke Standardized Classification and Diagnostic Evaluation (CASCADE) criteria facilitate a structured tool for categorizing and reporting childhood strokes according to the underlying cause. Our study aims to identify the prognostic value of CASCADE classification on admission for further course of arteriopathy and risk of stroke recurrence. Moreover, we give recommendations for follow-up imaging based on different CASCADE subgroups. Methods- Between 2004 and 2017, we identified 86 children with an acute arterial ischemic stroke classified in the 7-basic and 19-expanded subgroups of the acute CASCADE criteria. All included children were diagnosed and followed-up by magnetic resonance imaging. All arteriopathic strokes (basic subgroups 1-4 of acute CASCADE criteria) were further categorized into the chronic CASCADE criteria, including progressive, stable, reversible, and indeterminate course. Outcomes were defined as stroke recurrence and course of arteriopathy according to chronic CASCADE criteria. Associations between acute CASCADE criteria classification and stroke recurrence were assessed by Fisher exact test and between acute CASCADE criteria and chronic CASCADE criteria by Fisher exact test and Mann-Whitney U test. Results- A total of 86 children were included; of these, 57 presented with arteriopathic stroke (CASCADE 1-4) and 29 as nonarteriopathic. Unilateral cerebral arteriopathy (CASCADE 2; P=0.036) and bilateral cerebral arteriopathy (CASCADE 3; P=0.016) significantly correlated with stroke recurrence, and progressive arteriopathy significantly correlated with unilateral focal cerebral arteriopathy (P<0.001). Time points of progress of arteriopathy differed; whereas patients with unilateral focal cerebral arteriopathy presented with early median progress after 11 days, patients with bilateral cerebral arteriopathy had a significantly later median progress after 124 days (P=0.005). Conclusions- Initial CASCADE classification is associated with risk of recurrent strokes and progress of arteriopathy. Moreover, time points of arteriopathic progress vary according to the underlying cause.

5.
Plant Physiol ; 169(2): 1168-78, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26243620

RESUMO

Elevated carbon dioxide (CO2) in leaves closes stomatal apertures. Research has shown key functions of the ß-carbonic anhydrases (ßCA1 and ßCA4) in rapid CO2-induced stomatal movements by catalytic transmission of the CO2 signal in guard cells. However, the underlying mechanisms remain unclear, because initial studies indicate that these Arabidopsis (Arabidopsis thaliana) ßCAs are targeted to distinct intracellular compartments upon expression in tobacco (Nicotiana benthamiana) cells. Which cellular location of these enzymes plays a key role in native guard cells in CO2-regulated stomatal movements remains unknown. Here, we express fluorescently tagged CAs in guard cells of ca1ca4 double-mutant plants and show that the specific locations of ßCA4 at the plasma membrane and ßCA1 in native guard cell chloroplasts each can mediate rapid CO2 control of stomatal movements. Localization and complementation analyses using a mammalian αCAII-yellow fluorescent protein in guard cells further show that cytoplasmic localization is also sufficient to restore CO2 regulation of stomatal conductance. Mathematical modeling of cellular CO2 catalysis suggests that the dynamics of the intracellular HCO3 (-) concentration change in guard cells can be driven by plasma membrane and cytoplasmic localizations of CAs but not as clearly by chloroplast targeting. Moreover, modeling supports the notion that the intracellular HCO3 (-) concentration dynamics in guard cells are a key mechanism in mediating CO2-regulated stomatal movements but that an additional chloroplast role of CAs exists that has yet to be identified.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Dióxido de Carbono/metabolismo , Anidrases Carbônicas/metabolismo , Estômatos de Plantas/fisiologia , Sequência de Aminoácidos , Arabidopsis/citologia , Proteínas de Arabidopsis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Anidrases Carbônicas/genética , Membrana Celular/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Citosol/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Modelos Biológicos , Dados de Sequência Molecular , Células Vegetais/metabolismo , Estômatos de Plantas/metabolismo , Plantas Geneticamente Modificadas , Nicotiana/genética , Nicotiana/metabolismo
6.
J Neurol ; 271(8): 5003-5011, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38775933

RESUMO

BACKGROUND: Hematoma volume is a major pathophysiological hallmark of acute intracerebral hemorrhage (ICH). We investigated how the variance in functional outcome induced by the ICH volume is explained by neurological deficits at admission using a mediation model. METHODS: Patients with acute ICH treated in three tertiary stroke centers between January 2010 and April 2019 were retrospectively analyzed. Mediation analysis was performed to investigate the effect of ICH volume (0.8 ml (5% quantile) versus 130.6 ml (95% quantile)) on the risk of unfavorable functional outcome at discharge defined as modified Rankin Score (mRS) ≥ 3 with mediation through National Institutes of Health Stroke Scale (NIHSS) at admission. Multivariable regression was conducted to identify factors related to neurological improvement and deterioration. RESULTS: Three hundred thirty-eight patients were analyzed. One hundred twenty-one patients (36%) achieved mRS ≤ 3 at discharge. Mediation analysis showed that NIHSS on admission explained 30% [13%; 58%] of the ICH volume-induced variance in functional outcome at smaller ICH volume levels, and 14% [4%; 46%] at larger ICH volume levels. Higher ICH volume at admission and brainstem or intraventricular location of ICH were associated with neurological deterioration, while younger age, normotension, lower ICH volumes, and lobar location of ICH were predictors for neurological improvement. CONCLUSION: NIHSS at admission reflects 14% of the functional outcome at discharge for larger hematoma volumes and 30% for smaller hematoma volumes. These results underscore the importance of effects not reflected in NIHSS admission for the outcome of ICH patients such as secondary brain injury and early rehabilitation.


Assuntos
Hemorragia Cerebral , Humanos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Hemorragia Cerebral/fisiopatologia , Hemorragia Cerebral/diagnóstico por imagem , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Recuperação de Função Fisiológica/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Admissão do Paciente , Índice de Gravidade de Doença
7.
Mol Plant Microbe Interact ; 26(6): 626-32, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23441577

RESUMO

Guard cells regulate plant gas exchange and transpiration by modulation of stomatal aperture upon integrating external cues like photosynthetic effective illumination, CO2 levels and water availability and internal signals like abscisic acid (ABA). Being pores, stomata constitute a natural entry site for potentially harmful microbes. To prevent microbial invasion, stomata close upon perception of microbe-associated molecular patterns (MAMPs), and this represents an important layer of active immunity at the preinvasive level. The signaling pathways leading to stomatal closure triggered by biotic and abiotic stresses employ several common components, such as reactive oxygen species, calcium, kinases, and hormones, suggesting considerable intersection between MAMP- and ABA-induced stomatal closures, which we will discuss in this review.


Assuntos
Doenças das Plantas/imunologia , Estômatos de Plantas/imunologia , Plantas/imunologia , Transdução de Sinais/imunologia , Ácido Abscísico/metabolismo , Cálcio/metabolismo , Dióxido de Carbono/metabolismo , Óxido Nítrico/metabolismo , Fosfotransferases/metabolismo , Doenças das Plantas/microbiologia , Fenômenos Fisiológicos Vegetais , Proteínas de Plantas/metabolismo , Estômatos de Plantas/fisiologia , Plantas/enzimologia , Plantas/microbiologia , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico
8.
Front Mol Biosci ; 10: 1258374, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37860582

RESUMO

Background: Primary ciliary dyskinesia (PCD; MIM 242650) is a rare genetic disorder characterized by malfunction of the motile cilia resulting in reduced mucociliary clearance of the airways. Together with recurring infections of the lower respiratory tract, chronic rhinosinusitis (CRS) is a hallmark symptom of PCD. Data on genotype-phenotype correlations in the upper airways are scarce. Materials and methods: We investigated the prevalence, radiologic severity, and impact on health-related quality of life (HrQoL) of CRS in 58 individuals with genetically confirmed PCD. Subgroup analysis was performed according to the predicted ultrastructural phenotype based on genetic findings. Results: Among 58 individuals harboring pathogenic variants in 22 distinct genes associated with PCD, all were diagnosed with CRS, and 47% underwent sinus surgery. A total of 36 individuals answered a German-adapted version of the 20-item Sinonasal Outcome Test (SNOT-20-GAV) with a mean score of 35.8 ± 17, indicating a remarkably reduced HrQoL. Paranasal sinus imaging of 36 individuals showed moderate-to-severe opacification with an elevated Lund-Mackay Score (LMS) of 10.2 ± 4.4. Bilateral agenesis of frontal sinus (19%) and sphenoid sinus (9.5%) was a frequent finding in individuals aged 16 years or older. Subgroup analysis for predicted ultrastructural phenotypes did not identify differences in HrQoL, extent of sinus opacification, or frequency of aplastic paranasal sinuses. Conclusion: PCD is strongly associated with CRS. The high burden of disease is indicated by decreased HrQoL. Therefore, the upper airways of PCD individuals should be evaluated and managed by ear-nose-throat (ENT) specialists. Genetically determined PCD groups with predicted abnormal versus (near) normal ultrastructure did not differ in disease severity. Further studies are needed to gain evidence-based knowledge of the phenotype and management of upper airway manifestations in PCD. In addition, individuals with agenesis of the frontal and sphenoid paranasal sinuses and chronic respiratory symptoms should be considered for a diagnostic evaluation of PCD.

9.
Cells ; 12(7)2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-37048115

RESUMO

Microgravity (µg) has a massive impact on the health of space explorers. Microgravity changes the proliferation, differentiation, and growth of cells. As crewed spaceflights into deep space are being planned along with the commercialization of space travelling, researchers have focused on gene regulation in cells and organisms exposed to real (r-) and simulated (s-) µg. In particular, cancer and metastasis research benefits from the findings obtained under µg conditions. Gene regulation is a key factor in a cell or an organism's ability to sustain life and respond to environmental changes. It is a universal process to control the amount, location, and timing in which genes are expressed. In this review, we provide an overview of µg-induced changes in the numerous mechanisms involved in gene regulation, including regulatory proteins, microRNAs, and the chemical modification of DNA. In particular, we discuss the current knowledge about the impact of microgravity on gene regulation in different types of bacteria, protists, fungi, animals, humans, and cells with a focus on the brain, eye, endothelium, immune system, cartilage, muscle, bone, and various cancers as well as recent findings in plants. Importantly, the obtained data clearly imply that µg experiments can support translational medicine on Earth.


Assuntos
MicroRNAs , Voo Espacial , Ausência de Peso , Animais , Humanos , Regulação da Expressão Gênica , Diferenciação Celular , MicroRNAs/genética
10.
Plant J ; 67(1): 105-18, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21426425

RESUMO

Early rapid changes in response to the phytohormone abscisic acid (ABA) have been observed at the transcript level, but little is known how these transcript changes translate to changes in protein abundance under the same conditions. Here we have performed a global quantitative analysis of transcript and protein changes in Arabidopsis suspension cells in response to ABA using microarrays and quantitative proteomics. In summary, 3494 transcripts and 50 proteins were significantly regulated by ABA over a treatment period of 20-24 h. Abscisic acid also caused a rapid and strong increase in production of extracellular reactive oxygen species (ROS) with an average half-rise time of 33 sec. A subset of ABA-regulated transcripts were differentially regulated in the presence of the ROS scavenger dimethylthiourea (DMTU) as compared with ABA alone, suggesting a role for ROS in the regulation of these ABA-induced genes. Transcript changes showed an overall poor correlation to protein changes (r = 0.66). Only a subset of genes was regulated at the transcript and protein level, including known ABA marker genes. We furthermore identified ABA regulation of proteins that function in a branch of glucosinolate catabolism previously not associated with ABA signaling. The discovery of genes that were differentially regulated at the transcript and at the protein level emphasizes the strength of our combined approach. In summary, our dataset not only expands previous studies on gene and protein regulation in response to ABA, but rather uncovers unique aspects of the ABA regulon and gives rise to additional mechanisms regulated by ABA.


Assuntos
Ácido Abscísico/farmacologia , Arabidopsis/metabolismo , Perfilação da Expressão Gênica/métodos , Reguladores de Crescimento de Plantas/farmacologia , Proteômica/métodos , Espécies Reativas de Oxigênio/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Técnicas de Cultura de Células , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glucosinolatos/metabolismo , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/genética , RNA de Plantas/genética , Explosão Respiratória , Transdução de Sinais/efeitos dos fármacos , Tioureia/análogos & derivados , Tioureia/metabolismo
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