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1.
Nature ; 633(8031): 872-877, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39198644

RESUMO

Early plant responses to different stress situations often encompass cytosolic Ca2+ increases, plasma membrane depolarization and the generation of reactive oxygen species1-3. However, the mechanisms by which these signalling elements are translated into defined physiological outcomes are poorly understood. Here, to study the basis for encoding of specificity in plant signal processing, we used light-gated ion channels (channelrhodopsins). We developed a genetically engineered channelrhodopsin variant called XXM 2.0 with high Ca2+ conductance that enabled triggering cytosolic Ca2+ elevations in planta. Plant responses to light-induced Ca2+ influx through XXM 2.0 were studied side by side with effects caused by an anion efflux through the light-gated anion channelrhodopsin ACR1 2.04. Although both tools triggered membrane depolarizations, their activation led to distinct plant stress responses: XXM 2.0-induced Ca2+ signals stimulated production of reactive oxygen species and defence mechanisms; ACR1 2.0-mediated anion efflux triggered drought stress responses. Our findings imply that discrete Ca2+ signals and anion efflux serve as triggers for specific metabolic and transcriptional reprogramming enabling plants to adapt to particular stress situations. Our optogenetics approach unveiled that within plant leaves, distinct physiological responses are triggered by specific ion fluxes, which are accompanied by similar electrical signals.


Assuntos
Arabidopsis , Sinalização do Cálcio , Cálcio , Channelrhodopsins , Luz , Optogenética , Ânions/metabolismo , Arabidopsis/citologia , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/efeitos da radiação , Cálcio/metabolismo , Sinalização do Cálcio/efeitos da radiação , Membrana Celular/metabolismo , Membrana Celular/efeitos da radiação , Channelrhodopsins/metabolismo , Channelrhodopsins/genética , Citosol/metabolismo , Secas , Condutividade Elétrica , Transporte de Íons/efeitos da radiação , Folhas de Planta/genética , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/genética , Estresse Fisiológico/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos da radiação
2.
Nature ; 626(8001): 1073-1083, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38355792

RESUMO

Human cellular models of neurodegeneration require reproducibility and longevity, which is necessary for simulating age-dependent diseases. Such systems are particularly needed for TDP-43 proteinopathies1, which involve human-specific mechanisms2-5 that cannot be directly studied in animal models. Here, to explore the emergence and consequences of TDP-43 pathologies, we generated induced pluripotent stem cell-derived, colony morphology neural stem cells (iCoMoNSCs) via manual selection of neural precursors6. Single-cell transcriptomics and comparison to independent neural stem cells7 showed that iCoMoNSCs are uniquely homogenous and self-renewing. Differentiated iCoMoNSCs formed a self-organized multicellular system consisting of synaptically connected and electrophysiologically active neurons, which matured into long-lived functional networks (which we designate iNets). Neuronal and glial maturation in iNets was similar to that of cortical organoids8. Overexpression of wild-type TDP-43 in a minority of neurons within iNets led to progressive fragmentation and aggregation of the protein, resulting in a partial loss of function and neurotoxicity. Single-cell transcriptomics revealed a novel set of misregulated RNA targets in TDP-43-overexpressing neurons and in patients with TDP-43 proteinopathies exhibiting a loss of nuclear TDP-43. The strongest misregulated target encoded the synaptic protein NPTX2, the levels of which are controlled by TDP-43 binding on its 3' untranslated region. When NPTX2 was overexpressed in iNets, it exhibited neurotoxicity, whereas correcting NPTX2 misregulation partially rescued neurons from TDP-43-induced neurodegeneration. Notably, NPTX2 was consistently misaccumulated in neurons from patients with amyotrophic lateral sclerosis and frontotemporal lobar degeneration with TDP-43 pathology. Our work directly links TDP-43 misregulation and NPTX2 accumulation, thereby revealing a TDP-43-dependent pathway of neurotoxicity.


Assuntos
Esclerose Lateral Amiotrófica , Proteína C-Reativa , Proteínas de Ligação a DNA , Degeneração Lobar Frontotemporal , Rede Nervosa , Proteínas do Tecido Nervoso , Neurônios , Humanos , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Proteína C-Reativa/metabolismo , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/metabolismo , Degeneração Lobar Frontotemporal/metabolismo , Degeneração Lobar Frontotemporal/patologia , Rede Nervosa/metabolismo , Rede Nervosa/patologia , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/citologia , Neuroglia/citologia , Neurônios/citologia , Neurônios/metabolismo , Reprodutibilidade dos Testes
3.
Proc Natl Acad Sci U S A ; 121(7): e2313343121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38315839

RESUMO

Plants tightly control growth of their lateral organs, which led to the concept of apical dominance. However, outgrowth of the dormant lateral primordia is sensitive to the plant's nutritional status, resulting in an immense plasticity in plant architecture. While the impact of hormonal regulation on apical dominance is well characterized, the prime importance of sugar signaling to unleash lateral organ formation has just recently emerged. Here, we aimed to identify transcriptional regulators, which control the trade-off between growth of apical versus lateral organs. Making use of locally inducible gain-of-function as well as single and higher-order loss-of-function approaches of the sugar-responsive S1-basic-leucine-zipper (S1-bZIP) transcription factors, we disclosed their largely redundant function in establishing apical growth dominance. Consistently, comprehensive phenotypical and analytical studies of S1-bZIP mutants show a clear shift of sugar and organic nitrogen (N) allocation from apical to lateral organs, coinciding with strong lateral organ outgrowth. Tissue-specific transcriptomics reveal specific clade III SWEET sugar transporters, crucial for long-distance sugar transport to apical sinks and the glutaminase GLUTAMINE AMIDO-TRANSFERASE 1_2.1, involved in N homeostasis, as direct S1-bZIP targets, linking the architectural and metabolic mutant phenotypes to downstream gene regulation. Based on these results, we propose that S1-bZIPs control carbohydrate (C) partitioning from source leaves to apical organs and tune systemic N supply to restrict lateral organ formation by C/N depletion. Knowledge of the underlying mechanisms controlling plant C/N partitioning is of pivotal importance for breeding strategies to generate plants with desired architectural and nutritional characteristics.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica , Melhoramento Vegetal , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Plantas/metabolismo , Transdução de Sinais/genética , Açúcares , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
FASEB J ; 38(2): e23431, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38265294

RESUMO

Preeclampsia (PE) poses a considerable risk to the long-term cardiovascular health of both mothers and their offspring due to a hypoxic environment in the placenta leading to reduced fetal oxygen supply. Cholesterol is vital for fetal development by influencing placental function. Recent findings suggest an association between hypoxia, disturbed cholesterol homeostasis, and PE. This study investigates the influence of hypoxia on placental cholesterol homeostasis. Using primary human trophoblast cells and placentae from women with PE, various aspects of cholesterol homeostasis were examined under hypoxic and hypoxia/reoxygenation (H/R) conditions. Under hypoxia and H/R, intracellular total and non-esterified cholesterol levels were significantly increased. This coincided with an upregulation of HMG-CoA-reductase and HMG-CoA-synthase (key genes regulating cholesterol biosynthesis), and a decrease in acetyl-CoA-acetyltransferase-1 (ACAT1), which mediates cholesterol esterification. Hypoxia and H/R also increased the intracellular levels of reactive oxygen species and elevated the expression of hypoxia-inducible factor (HIF)-2α and sterol-regulatory-element-binding-protein (SREBP) transcription factors. Additionally, exposure of trophoblasts to hypoxia and H/R resulted in enhanced cholesterol efflux to maternal and fetal serum. This was accompanied by an increased expression of proteins involved in cholesterol transport such as the scavenger receptor class B type I (SR-BI) and the ATP-binding cassette transporter G1 (ABCG1). Despite these metabolic alterations, mitogen-activated-protein-kinase (MAPK) signaling, a key regulator of cholesterol homeostasis, was largely unaffected. Our findings indicate dysregulation of cholesterol homeostasis at multiple metabolic points in both the trophoblast hypoxia model and placentae from women with PE. The increased cholesterol efflux and intracellular accumulation of non-esterified cholesterol may have critical implications for both the mother and the fetus during pregnancy, potentially contributing to an elevated cardiovascular risk later in life.


Assuntos
Placenta , Pré-Eclâmpsia , Gravidez , Humanos , Feminino , Transporte Biológico , Hipóxia , Homeostase
5.
Plant J ; 115(1): 81-96, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36976526

RESUMO

Heat stress triggers the accumulation of triacylglycerols in Arabidopsis leaves, which increases basal thermotolerance. However, how triacylglycerol synthesis is linked to thermotolerance remains unclear and the mechanisms involved remain to be elucidated. It has been shown that triacylglycerol and starch degradation are required to provide energy for stomatal opening induced by blue light at dawn. To investigate whether triacylglycerol turnover is involved in heat-induced stomatal opening during the day, we performed feeding experiments with labeled fatty acids. Heat stress strongly induced both triacylglycerol synthesis and degradation to channel fatty acids destined for peroxisomal ß-oxidation through the triacylglycerol pool. Analysis of mutants defective in triacylglycerol synthesis or peroxisomal fatty acid uptake revealed that triacylglycerol turnover and fatty acid catabolism are required for heat-induced stomatal opening in illuminated leaves. We show that triacylglycerol turnover is continuous (1.2 mol% per min) in illuminated leaves even at 22°C. The ß-oxidation of triacylglycerol-derived fatty acids generates C2 carbon units that are channeled into the tricarboxylic acid pathway in the light. In addition, carbohydrate catabolism is required to provide oxaloacetate as an acceptor for peroxisomal acetyl-CoA and maintain the tricarboxylic acid pathway for energy and amino acid production during the day.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Triglicerídeos/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ácidos Graxos/metabolismo , Resposta ao Choque Térmico , Luz , Estômatos de Plantas/metabolismo
6.
Stroke ; 55(5): 1235-1244, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38511386

RESUMO

BACKGROUND: The relationship between dynamic cerebral autoregulation (dCA) and functional outcome after acute ischemic stroke (AIS) is unclear. Previous studies are limited by small sample sizes and heterogeneity. METHODS: We performed a 1-stage individual patient data meta-analysis to investigate associations between dCA and functional outcome after AIS. Participating centers were identified through a systematic search of the literature and direct invitation. We included centers with dCA data within 1 year of AIS in adults aged over 18 years, excluding intracerebral or subarachnoid hemorrhage. Data were obtained on phase, gain, coherence, and autoregulation index derived from transfer function analysis at low-frequency and very low-frequency bands. Cerebral blood velocity, arterial pressure, end-tidal carbon dioxide, heart rate, stroke severity and sub-type, and comorbidities were collected where available. Data were grouped into 4 time points after AIS: <24 hours, 24 to 72 hours, 4 to 7 days, and >3 months. The modified Rankin Scale assessed functional outcome at 3 months. Modified Rankin Scale was analyzed as both dichotomized (0 to 2 versus 3 to 6) and ordinal (modified Rankin Scale scores, 0-6) outcomes. Univariable and multivariable analyses were conducted to identify significant relationships between dCA parameters, comorbidities, and outcomes, for each time point using generalized linear (dichotomized outcome), or cumulative link (ordinal outcome) mixed models. The participating center was modeled as a random intercept to generate odds ratios with 95% CIs. RESULTS: The sample included 384 individuals (35% women) from 7 centers, aged 66.3±13.7 years, with predominantly nonlacunar stroke (n=348, 69%). In the affected hemisphere, higher phase at very low-frequency predicted better outcome (dichotomized modified Rankin Scale) at <24 (crude odds ratios, 2.17 [95% CI, 1.47-3.19]; P<0.001) hours, 24-72 (crude odds ratios, 1.95 [95% CI, 1.21-3.13]; P=0.006) hours, and phase at low-frequency predicted outcome at 3 (crude odds ratios, 3.03 [95% CI, 1.10-8.33]; P=0.032) months. These results remained after covariate adjustment. CONCLUSIONS: Greater transfer function analysis-derived phase was associated with improved functional outcome at 3 months after AIS. dCA parameters in the early phase of AIS may help to predict functional outcome.

7.
J Lipid Res ; 64(10): 100417, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37481037

RESUMO

Modern lifestyle is often at odds with endogenously driven rhythmicity, which can lead to circadian disruption and metabolic syndrome. One signature for circadian disruption is a reduced or altered metabolite cycling in the circulating tissue reflecting the current metabolic status. Drosophila is a well-established model in chronobiology, but day-time dependent variations of transport metabolites in the fly circulation are poorly characterized. Here, we sampled fly hemolymph throughout the day and analyzed diacylglycerols (DGs), phosphoethanolamines (PEs) and phosphocholines (PCs) using LC-MS. In wild-type flies kept on sugar-only medium under a light-dark cycle, all transport lipid species showed a synchronized bimodal oscillation pattern with maxima at the beginning and end of the light phase which were impaired in period01 clock mutants. In wild-type flies under constant dark conditions, the oscillation became monophasic with a maximum in the middle of the subjective day. In strong support of clock-driven oscillations, levels of the targeted lipids peaked once in the middle of the light phase under time-restricted feeding independent of the time of food intake. When wild-type flies were reared on full standard medium, the rhythmic alterations of hemolymph lipid levels were greatly attenuated. Our data suggest that the circadian clock aligns daily oscillations of DGs, PEs, and PCs in the hemolymph to the anabolic siesta phase, with a strong influence of light on phase and modality.

8.
J Biol Chem ; 298(11): 102519, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36152752

RESUMO

Plants and algae are faced with a conundrum: harvesting sufficient light to drive their metabolic needs while dissipating light in excess to prevent photodamage, a process known as nonphotochemical quenching. A slowly relaxing form of energy dissipation, termed qH, is critical for plants' survival under abiotic stress; however, qH location in the photosynthetic membrane is unresolved. Here, we tested whether we could isolate subcomplexes from plants in which qH was induced that would remain in an energy-dissipative state. Interestingly, we found that chlorophyll (Chl) fluorescence lifetimes were decreased by qH in isolated major trimeric antenna complexes, indicating that they serve as a site for qH-energy dissipation and providing a natively quenched complex with physiological relevance to natural conditions. Next, we monitored the changes in thylakoid pigment, protein, and lipid contents of antenna with active or inactive qH but did not detect any evident differences. Finally, we investigated whether specific subunits of the major antenna complexes were required for qH but found that qH was insensitive to trimer composition. Because we previously observed that qH can occur in the absence of specific xanthophylls, and no evident changes in pigments, proteins, or lipids were detected, we tentatively propose that the energy-dissipative state reported here may stem from Chl-Chl excitonic interaction.


Assuntos
Clorofila , Complexos de Proteínas Captadores de Luz , Complexo de Proteína do Fotossistema II , Plantas , Clorofila/química , Luz , Complexos de Proteínas Captadores de Luz/química , Fotossíntese , Complexo de Proteína do Fotossistema II/química , Plantas/química , Tilacoides/química , Xantofilas/química
9.
Plant Cell Environ ; 46(11): 3392-3404, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37427798

RESUMO

High-temperature stress limits plant growth and reproduction. Exposure to high temperature, however, also elicits a physiological response, which protects plants from the damage evoked by heat. This response involves a partial reconfiguration of the metabolome including the accumulation of the trisaccharide raffinose. In this study, we explored the intraspecific variation of warm temperature-induced raffinose accumulation as a metabolic marker for temperature responsiveness with the aim to identify genes that contribute to thermotolerance. By combining raffinose measurements in 250 Arabidopsis thaliana accessions following a mild heat treatment with genome-wide association studies, we identified five genomic regions that were associated with the observed trait variation. Subsequent functional analyses confirmed a causal relationship between TREHALOSE-6-PHOSPHATE SYNTHASE 1 (TPS1) and warm temperature-dependent raffinose synthesis. Moreover, complementation of the tps1-1 null mutant with functionally distinct TPS1 isoforms differentially affected carbohydrate metabolism under more severe heat stress. While higher TPS1 activity was associated with reduced endogenous sucrose levels and thermotolerance, disruption of trehalose 6-phosphate signalling resulted in higher accumulation of transitory starch and sucrose and was associated with enhanced heat resistance. Taken together, our findings suggest a role of trehalose 6-phosphate in thermotolerance, most likely through its regulatory function in carbon partitioning and sucrose homoeostasis.


Assuntos
Arabidopsis , Termotolerância , Temperatura , Rafinose , Termotolerância/genética , Trealose/metabolismo , Estudo de Associação Genômica Ampla , Arabidopsis/metabolismo , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Sacarose , Fosfatos
10.
Plant Physiol ; 185(2): 331-351, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33721895

RESUMO

Carotenoid levels in plant tissues depend on the relative rates of synthesis and degradation of the molecules in the pathway. While plant carotenoid biosynthesis has been extensively characterized, research on carotenoid degradation and catabolism into apocarotenoids is a relatively novel field. To identify apocarotenoid metabolic processes, we characterized the transcriptome of transgenic Arabidopsis (Arabidopsis thaliana) roots accumulating high levels of ß-carotene and, consequently, ß-apocarotenoids. Transcriptome analysis revealed feedback regulation on carotenogenic gene transcripts suitable for reducing ß-carotene levels, suggesting involvement of specific apocarotenoid signaling molecules originating directly from ß-carotene degradation or after secondary enzymatic derivatizations. Enzymes implicated in apocarotenoid modification reactions overlapped with detoxification enzymes of xenobiotics and reactive carbonyl species (RCS), while metabolite analysis excluded lipid stress response, a potential secondary effect of carotenoid accumulation. In agreement with structural similarities between RCS and ß-apocarotenoids, RCS detoxification enzymes also converted apocarotenoids derived from ß-carotene and from xanthophylls into apocarotenols and apocarotenoic acids in vitro. Moreover, glycosylation and glutathionylation-related processes and translocators were induced. In view of similarities to mechanisms found in crocin biosynthesis and cellular deposition in saffron (Crocus sativus), our data suggest apocarotenoid metabolization, derivatization and compartmentalization as key processes in (apo)carotenoid metabolism in plants.


Assuntos
Arabidopsis/metabolismo , Carotenoides/metabolismo , Proteínas de Plantas/metabolismo , Transcriptoma , Xenobióticos/metabolismo , Arabidopsis/genética , Radicais Livres/metabolismo , Perfilação da Expressão Gênica , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Xantofilas/metabolismo
11.
J Econ Psychol ; 93: 102572, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36267496

RESUMO

In a scenario study with 1200 Austrian taxpayers, we examined how tax compliance is affected by the economic crisis related to the COVID-19 pandemic. Moreover, we investigated the potential of trust in government, attitude towards taxes, and justice perceptions in mitigating potential effects. The results suggest a strong effect of the economic environment on tax compliance. Specifically, tax compliance was lower in scenarios where the pandemic had a negative effect on the economy than in scenarios with no negative effect. However, for individuals with a positive attitude towards taxes, compliance was not lower in a negative economic environment than in pre-COVID-19 times. Moreover, we found that taxpayers who were not affected economically, taxpayers with a positive attitude towards taxes, and taxpayers with a low propensity to take risks generally indicated higher levels of tax compliance. Exploratory analyses indicate that taxpayers who change their compliance behavior in response to the economic environment are, on average, younger, less educated, more strongly affected economically, and more uncertain about their current economic situation than taxpayers with stable compliance levels. Policy interventions should target these groups to strengthen tax compliance in times of crisis.

12.
New Phytol ; 231(3): 1040-1055, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33774818

RESUMO

Soil salinity is an increasingly global problem which hampers plant growth and crop yield. Plant productivity depends on optimal water-use efficiency and photosynthetic capacity balanced by stomatal conductance. Whether and how stomatal behavior contributes to salt sensitivity or tolerance is currently unknown. This work identifies guard cell-specific signaling networks exerted by a salt-sensitive and salt-tolerant plant under ionic and osmotic stress conditions accompanied by increasing NaCl loads. We challenged soil-grown Arabidopsis thaliana and Thellungiella salsuginea plants with short- and long-term salinity stress and monitored genome-wide gene expression and signals of guard cells that determine their function. Arabidopsis plants suffered from both salt regimes and showed reduced stomatal conductance while Thellungiella displayed no obvious stress symptoms. The salt-dependent gene expression changes of guard cells supported the ability of the halophyte to maintain high potassium to sodium ratios and to attenuate the abscisic acid (ABA) signaling pathway which the glycophyte kept activated despite fading ABA concentrations. Our study shows that salinity stress and even the different tolerances are manifested on a single cell level. Halophytic guard cells are less sensitive than glycophytic guard cells, providing opportunities to manipulate stomatal behavior and improve plant productivity.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Transporte de Íons , Estômatos de Plantas/metabolismo , Estresse Salino , Plantas Tolerantes a Sal/metabolismo
13.
Reprod Biomed Online ; 42(1): 185-206, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33191131

RESUMO

This study aimed to investigate the association of adenomyosis with fertility, pregnancy and neonatal outcomes. An electronic search was conducted using the MEDLINE, PubMed and Cochrane databases up to April 2020. Seventeen observational studies were included. Adenomyosis was significantly associated with a lower clinical pregnancy rate (odds ratio [OR] 0.69; 95% confidence interval [CI] 0.51-0.94) and higher miscarriage rate (OR 2.17; 95% CI 1.25-3.79) after treatment with assisted reproductive technology (ART). The lower clinical pregnancy rate was more significant in the subgroup of patients with short down-regulation protocols. Similar associations were recorded after age adjustment. Adenomyosis was also significantly associated with an increased risk of pre-eclampsia, preterm delivery, Caesarean section, fetal malpresentation, small for gestational age infancy and post-partum haemorrhage, which was confirmed after correction for age and mode of conception. In conclusion, adenomyosis is associated with negative effects on fertility after ART. The potentially protective role of the ultra-long down-regulation protocols needs further evaluation in randomized controlled studies. Adenomyosis is also associated (independently of the mode of conception) with adverse pregnancy and neonatal outcomes. Proper counselling prior to ART and close monitoring of pregnancy in patients with adenomyosis should be recommended.


Assuntos
Adenomiose/complicações , Infertilidade Feminina/etiologia , Complicações na Gravidez/etiologia , Resultado da Gravidez , Feminino , Fertilidade , Humanos , Recém-Nascido , Gravidez , Taxa de Gravidez , Técnicas de Reprodução Assistida/estatística & dados numéricos
14.
BMC Pregnancy Childbirth ; 21(1): 728, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34706693

RESUMO

BACKGROUND: Healthy women with low risk singleton pregnancies are offered a midwife-led birth model at our department. Exclusion criteria for midwife-led births include a range of abnormalities in medical history and during the course of pregnancy. In case of complications before, during or after labor and birth, an obstetrician is involved. The purpose of this study was 1) to evaluate the frequency of and reasons for secondary obstetrician involvement in planned midwife-led births and 2) to assess the maternal and neonatal outcome. METHODS: We analyzed a cohort of planned midwife-led births during a 14 years period (2006-2019). Evaluation included a comparison between midwife-led births with or without secondary obstetrician involvement, regarding maternal characteristics, birth mode, and maternal and neonatal outcome. Statistical analysis was performed by unpaired t-tests and Chi-square tests. RESULTS: In total, there were 532 intended midwife-led births between 2006 and 2019 (2.6% of all births during this time-period at the department). Among these, 302 (57%) women had spontaneous vaginal births as midwife-led births. In the remaining 230 (43%) births, obstetricians were involved: 62% of women with obstetrician involvement had spontaneous vaginal births, 25% instrumental vaginal births and 13% caesarean sections. Overall, the caesarean section rate was 5.6% in the whole cohort of women with intended midwife-led births. Reasons for obstetrician involvement primarily included necessity for labor induction, abnormal fetal heart rate monitoring, thick meconium-stained amniotic fluid, prolonged first or second stage of labor, desire for epidural analgesia, obstetrical anal sphincter injuries, retention of placenta and postpartum hemorrhage. There was a significantly higher rate of primiparous women in the group with obstetrician involvement. Arterial umbilical cord pH < 7.10 occurred significantly more often in the group with obstetrician involvement, while 5' Apgar score < 7 did not differ significantly. The overall transfer rate of newborns to neonatal intensive care unit was low (1.3%). CONCLUSION: A midwife-led birth in our setting is a safe alternative to a primarily obstetrician-led birth, provided that selection criteria are being followed and prompt obstetrician involvement is available in case of abnormal course of labor and birth or postpartum complications.


Assuntos
Parto Obstétrico/estatística & dados numéricos , Tocologia/estatística & dados numéricos , Complicações do Trabalho de Parto/epidemiologia , Parto , Médicos , Adulto , Estudos de Coortes , Feminino , Hospitais Universitários , Humanos , Complicações do Trabalho de Parto/prevenção & controle , Unidade Hospitalar de Ginecologia e Obstetrícia , Gravidez , Estudos Retrospectivos , Suíça/epidemiologia
15.
Cell Mol Life Sci ; 77(23): 4939-4956, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31960114

RESUMO

The fruit fly Drosophila is a prime model in circadian research, but still little is known about its circadian regulation of metabolism. Daily rhythmicity in levels of several metabolites has been found, but knowledge about hydrophobic metabolites is limited. We here compared metabolite levels including lipids between period01 (per01) clock mutants and Canton-S wildtype (WTCS) flies in an isogenic and non-isogenic background using LC-MS. In the non-isogenic background, metabolites with differing levels comprised essential amino acids, kynurenines, pterinates, glycero(phospho)lipids, and fatty acid esters. Notably, detectable diacylglycerols (DAG) and acylcarnitines (AC), involved in lipid metabolism, showed lower levels in per01 mutants. Most of these differences disappeared in the isogenic background, yet the level differences for AC as well as DAG were consistent for fly bodies. AC levels were dependent on the time of day in WTCS in phase with food consumption under LD conditions, while DAGs showed weak daily oscillations. Two short-chain ACs continued to cycle even in constant darkness. per01 mutants in LD showed no or very weak diel AC oscillations out of phase with feeding activity. The low levels of DAGs and ACs in per01 did not correlate with lower total food consumption, body mass or weight. Clock mutant flies showed higher sensitivity to starvation independent of their background-dependent activity level. Our results suggest that neither feeding, energy storage nor mobilisation is significantly affected in per01 mutants, but point towards impaired mitochondrial activity, supported by upregulation of the mitochondrial stress marker 4EBP in the clock mutants.


Assuntos
Relógios Circadianos/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Metabolismo dos Lipídeos/genética , Mutação com Perda de Função/genética , Proteínas Circadianas Period/genética , Inanição/genética , Animais , Biomarcadores/metabolismo , Carnitina/análogos & derivados , Carnitina/metabolismo , Ritmo Circadiano , Proteínas de Drosophila/metabolismo , Comportamento Alimentar , Lipídeos/análise , Masculino , Metaboloma , Atividade Motora , Proteínas Circadianas Period/metabolismo , Estresse Fisiológico , Triptofano/metabolismo
16.
BMC Geriatr ; 21(1): 646, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34784883

RESUMO

BACKGROUND: Among potentially modifiable risk factors for delirium, transfers between wards, hospitals and other facilities have been mentioned with low evidence. TRADE (TRAnsport and DElirium in older people) was set up to investigate i) the impact of transfer and/or discharge on the onset of delirium in older adults and ii) feasibility and acceptance of a developed complex intervention targeting caregiver's participation during and after hospital discharge or transfer on cognition and the onset of delirium in older adults. METHODS: The study is designed according to the guidelines of the UK Medical Research Council (MRC) for development and evaluation of complex interventions and comprises two steps: development and feasibility/piloting. The development phase includes i) a multicenter observational prospective cohort study to assess delirium incidence and cognitive decline associated with transfer and discharge, ii) a systematic review of the literature, iii) stakeholder focus group interviews and iv) an expert workshop followed by a Delphi survey. Based on this information, a complex intervention to better and systematically involve family caregivers in discharge and transport was developed. The intervention will be tested in a pilot study using a stepped wedge design with a detailed process and health economic evaluation. The study is conducted at four acute care hospitals in southwest Germany. Primary endpoints are the delirium incidence and cognitive function. Secondary endpoints include prevalence of caregiver companionship, functional decline, cost and cost effectiveness, quality of discharge management and quality of admission management in admitting hospitals or nursing homes. Data will be collected prior to discharge as well as after 3, 7 and 90 days. DISCUSSION: TRADE will help to evaluate transfer and discharge as a possible risk factor for delirium. In addition, TRADE evaluates the impact and modifiability of caregiver's participation during patient's transfer or discharge on delirium incidence and cognitive decline providing the foundation for a confirmatory implementation study. TRIAL REGISTRATION: DRKS (Deutsches Register für klinische Studien) DRKS00017828 . Registered on 17th September 2019. Retrospectively registered.


Assuntos
Delírio , Alta do Paciente , Idoso , Cuidadores , Delírio/diagnóstico , Delírio/epidemiologia , Delírio/prevenção & controle , Hospitais , Humanos , Estudos Multicêntricos como Assunto , Projetos Piloto , Estudos Prospectivos , Revisões Sistemáticas como Assunto
17.
Arch Gynecol Obstet ; 303(1): 121-128, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32813046

RESUMO

PURPOSE: Peripartum hemorrhage (PPH) remains one of the main causes of maternal mortality worldwide. Treatment includes administration of packed red blood cells (RBC) in severe cases and patient blood management (PBM) may reduce it significantly. In our study, we wanted to retrospectively assess red blood cell administration in PPH to evaluate the impact of PBM in Switzerland. METHODS: Using data from the Swiss obstetric hospital registry (Arbeitsgemeinschaft Schweizer Frauenkliniken, ASF), we included patients with deliveries from 1998 to 2016. We examined available obstetric data as well as blood loss and RBC administration in the acute and subacute peripartal phase. We categorized data into two time intervals: 1998-2011 and 2012-2016, as new PPH guidelines in Switzerland were established in 2012. RESULTS: PPH incidence increased between 1998 and 2016 significantly. The number of vaginal instrumental deliveries and cesarean sections increased as well. Administration of three or more RBC units, as defined in the ASF registry, in the acute and subacute phase in Switzerland has decreased after 2012. Conversely, we saw an increase in the administration of one to two RBC units in the acute and subacute phase. Nevertheless, overall RBC administration has been decreasing from 1998 to 2016. CONCLUSION: The increase of patients obtaining one or two units of RBC for PPH suggests that there may be a potential for effective implication of PBM in obstetrics. Reduction of RBC transfusion in the context of PPH may not only decrease maternal morbidity, but decrease economic costs as well.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Eritrócitos/métodos , Hemorragia Pós-Parto/terapia , Adulto , Parto Obstétrico/efeitos adversos , Transfusão de Eritrócitos/efeitos adversos , Feminino , Humanos , Incidência , Hemorragia Pós-Parto/epidemiologia , Hemorragia Pós-Parto/etiologia , Período Pós-Parto , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Fatores de Risco , Suíça/epidemiologia
18.
Lancet ; 393(10172): 664-677, 2019 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-30782342

RESUMO

BACKGROUND: In laboratory animals, exposure to most general anaesthetics leads to neurotoxicity manifested by neuronal cell death and abnormal behaviour and cognition. Some large human cohort studies have shown an association between general anaesthesia at a young age and subsequent neurodevelopmental deficits, but these studies are prone to bias. Others have found no evidence for an association. We aimed to establish whether general anaesthesia in early infancy affects neurodevelopmental outcomes. METHODS: In this international, assessor-masked, equivalence, randomised, controlled trial conducted at 28 hospitals in Australia, Italy, the USA, the UK, Canada, the Netherlands, and New Zealand, we recruited infants of less than 60 weeks' postmenstrual age who were born at more than 26 weeks' gestation and were undergoing inguinal herniorrhaphy, without previous exposure to general anaesthesia or risk factors for neurological injury. Patients were randomly assigned (1:1) by use of a web-based randomisation service to receive either awake-regional anaesthetic or sevoflurane-based general anaesthetic. Anaesthetists were aware of group allocation, but individuals administering the neurodevelopmental assessments were not. Parents were informed of their infants group allocation upon request, but were told to mask this information from assessors. The primary outcome measure was full-scale intelligence quotient (FSIQ) on the Wechsler Preschool and Primary Scale of Intelligence, third edition (WPPSI-III), at 5 years of age. The primary analysis was done on a per-protocol basis, adjusted for gestational age at birth and country, with multiple imputation used to account for missing data. An intention-to-treat analysis was also done. A difference in means of 5 points was predefined as the clinical equivalence margin. This completed trial is registered with ANZCTR, number ACTRN12606000441516, and ClinicalTrials.gov, number NCT00756600. FINDINGS: Between Feb 9, 2007, and Jan 31, 2013, 4023 infants were screened and 722 were randomly allocated: 363 (50%) to the awake-regional anaesthesia group and 359 (50%) to the general anaesthesia group. There were 74 protocol violations in the awake-regional anaesthesia group and two in the general anaesthesia group. Primary outcome data for the per-protocol analysis were obtained from 205 children in the awake-regional anaesthesia group and 242 in the general anaesthesia group. The median duration of general anaesthesia was 54 min (IQR 41-70). The mean FSIQ score was 99·08 (SD 18·35) in the awake-regional anaesthesia group and 98·97 (19·66) in the general anaesthesia group, with a difference in means (awake-regional anaesthesia minus general anaesthesia) of 0·23 (95% CI -2·59 to 3·06), providing strong evidence of equivalence. The results of the intention-to-treat analysis were similar to those of the per-protocol analysis. INTERPRETATION: Slightly less than 1 h of general anaesthesia in early infancy does not alter neurodevelopmental outcome at age 5 years compared with awake-regional anaesthesia in a predominantly male study population. FUNDING: US National Institutes of Health, US Food and Drug Administration, Thrasher Research Fund, Australian National Health and Medical Research Council, Health Technologies Assessment-National Institute for Health Research (UK), Australian and New Zealand College of Anaesthetists, Murdoch Children's Research Institute, Canadian Institutes of Health Research, Canadian Anesthesiologists Society, Pfizer Canada, Italian Ministry of Health, Fonds NutsOhra, UK Clinical Research Network, Perth Children's Hospital Foundation, the Stan Perron Charitable Trust, and the Callahan Estate.


Assuntos
Anestesia Geral/efeitos adversos , Internacionalidade , Escalas de Wechsler/estatística & dados numéricos , Desenvolvimento Infantil/efeitos dos fármacos , Pré-Escolar , Feminino , Hérnia Inguinal/cirurgia , Humanos , Lactente , Recém-Nascido , Masculino , Fatores de Risco
19.
Blood ; 132(9): 948-961, 2018 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-29967129

RESUMO

Genomic events associated with poor outcome in chronic myeloid leukemia (CML) are poorly understood. We performed whole-exome sequencing, copy-number variation, and/or RNA sequencing for 65 patients to discover mutations at diagnosis and blast crisis (BC). Forty-six patients with chronic-phase disease with the extremes of outcome were studied at diagnosis. Cancer gene variants were detected in 15 (56%) of 27 patients with subsequent BC or poor outcome and in 3 (16%) of 19 optimal responders (P = .007). Frequently mutated genes at diagnosis were ASXL1, IKZF1, and RUNX1 The methyltransferase SETD1B was a novel recurrently mutated gene. A novel class of variant associated with the Philadelphia (Ph) translocation was detected at diagnosis in 11 (24%) of 46 patients comprising fusions and/or rearrangement of genes on the translocated chromosomes, with evidence of fragmentation, inversion, and imperfect sequence reassembly. These were more frequent at diagnosis in patients with poor outcome: 9 (33%) of 27 vs 2 (11%) of 19 optimal responders (P = .07). Thirty-nine patients were tested at BC, and all had cancer gene variants, including ABL1 kinase domain mutations in 58%. However, ABL1 mutations cooccurred with other mutated cancer genes in 89% of cases, and these predated ABL1 mutations in 62% of evaluable patients. Gene fusions not associated with the Ph translocation occurred in 42% of patients at BC and commonly involved fusion partners that were known cancer genes (78%). Genomic analysis revealed numerous relevant variants at diagnosis in patients with poor outcome and all patients at BC. Future refined biomarker testing of specific variants will likely provide prognostic information to facilitate a risk-adapted therapeutic approach.


Assuntos
Biomarcadores Tumorais/genética , Genômica , Leucemia Mielogênica Crônica BCR-ABL Positiva , Proteínas de Neoplasias/genética , Cromossomo Filadélfia , Translocação Genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Taxa de Sobrevida
20.
Acta Obstet Gynecol Scand ; 99(3): 357-363, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31587255

RESUMO

INTRODUCTION: Preterm birth is a major cause of neonatal morbidity and mortality. There is an urgent need to accurately predict imminent delivery to enable necessary interventions such as tocolytic, glucocorticoid, and magnesium sulfate administration. We aimed to evaluate placental α-macroglobulin-1 as a new diagnostic marker in the prediction of preterm birth. MATERIAL AND METHODS: We performed a prospective observational trial in women with intact membranes between 24+0 and 36+6 weeks of gestation. We included both women with and without threatened preterm labor symptoms. We evaluated the test performance of placental α-macroglobulin-1 measurements in cervicovaginal fluid regarding three different presentation-to-delivery intervals: ≤2, ≤7, ≤14 days. In addition, we calculated placental α-macroglobulin-1 performance in combination with other prognostic factors such as ultrasonographic cervical length measurements. RESULTS: We included 126 women in the study. We detected high specificity (97%-98%) and negative predictive value (89%-97%) for placental α-macroglobulin-1 at all time intervals. We assessed placental α-macroglobulin-1 in combination with cervical length measurements (≤15 mm) in the sub-group of women presenting with threatened preterm labor symptoms (n = 63) and detected high positive predictive values (100%) for 7- and 14-day presentation-to-delivery intervals. CONCLUSIONS: Our study provides evidence that placental α-macroglobulin-1 testing in cervicovaginal fluid, in combination with cervical length measurements, accurately predicts preterm birth in women with preterm labor symptoms. This novel test combination may be used clinically to triage women presenting with threatened preterm labor, avoiding overtreatment and unnecessary hospitalizations.


Assuntos
Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Trabalho de Parto Prematuro , Nascimento Prematuro/diagnóstico , Diagnóstico Pré-Natal , alfa-Macroglobulinas/metabolismo , Adulto , Medida do Comprimento Cervical , Feminino , Humanos , Valor Preditivo dos Testes , Gravidez , Terceiro Trimestre da Gravidez , Nascimento Prematuro/sangue , Nascimento Prematuro/prevenção & controle , Estudos Prospectivos , Sensibilidade e Especificidade
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