Publications by authors named "Koen Veys"

The calculation of fluorescence quantum yields (FQYs) and lifetimes of organic dyes remains very challenging. In this article, we extensively test the machinery to calculate FQYs. Specifically, we perform an extensive analysis on the parameters influencing the intersystem crossing (ISC), internal conversion (IC), and fluorescence rate constants calculations.

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In this Perspective, we discuss recent advances made to evaluate from first-principles the excited-state decay rate constants of organic fluorophores, focusing on the so-called strategy. In this strategy, one essentially takes advantage of Fermi's golden rule (FGR) to evaluate rate constants at key points of the potential energy surfaces, a procedure that can be refined in a variety of ways. In this way, the radiative rate constant can be straightforwardly obtained by integrating the fluorescence line shape, itself determined from vibronic calculations.

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Angiogenesis and lymphangiogenesis, the formation of new blood or lymphatic vessels, respectively, from preexisting vasculature is essential during embryonic development, but also occurs during tissue repair and in pathological conditions (cancer; ocular disease; ischemic, infectious and inflammatory disorders), which are all characterized to a certain extent by inflammatory conditions. Hence, a rapid, inexpensive, feasible / technically easy, reliable assay of inflammation-induced (lymph-)angiogenesis is highly valuable. In this context, the corneal thermal cauterization assay in mice is a simple, low-cost, reproducible, insightful and labor-saving assay to gauge the role of inflammation in angiogenesis and lymphangiogenesis.

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Defining a theoretical model systematically delivering accurate predictions of the fluorescence quantum yields of organic dyes is highly desirable for designing improved fluorophores in a systematic rather than trial-and-error way. To this end, the first required step is to obtain reliable radiative rates (), as low typically precludes effective emission. In the present contribution, using a series of 10 substituted phenyls with known experimental , we analyze the impact of the computational protocol on the determined through the thermal vibration correlation function (TVCF) approach on the basis of time-dependent density functional theory (TD-DFT) calculations of the energies, structures, and vibrational parameters.

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Article Synopsis
  • Scientists did a big review to learn about platelet transfusions, which help stop bleeding in patients.
  • They looked at 110 studies to understand how effective these transfusions are and how they should be done.
  • They created an interactive map to help other researchers find information and avoid repeating the same studies.
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Internal conversion (IC) coupled to vibrational relaxation (VR) in molecular chromophores is a source of major energy losses in natural and artificial solar-to-chemical energy conversion schemes. The development of anti-Kasha chromophores, where dissipative IC channels are blocked, is a promising strategy to boost energy conversion efficiencies. In this contribution, we demonstrate the presence of an unusually high kinetic barrier for IC in [Ru(tpm)(bpy)(NCS)] (RuNCS), where tpm is tris(1-pyrazolyl)methane and bpy is 2,2'-bipyridine, by means of an arsenal of temperature-dependent spectroscopic methods including nanosecond and femtosecond transient absorption spectroscopies.

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According to Kasha's rule, the emission of a photon in a molecular system always comes from the lowest excited state. A corollary of this rule (i.e.

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Endothelial cells (ECs) harbor distinct phenotypical and functional characteristics depending on their tissue localization and contribute to brain, eye, lung, and muscle diseases such as dementia, macular degeneration, pulmonary hypertension, and sarcopenia. To study their function, isolation of pure ECs in high quantities is crucial. Here, we describe protocols for rapid and reproducible blood vessel EC purification established for scRNA sequencing from murine tissues using mechanical and enzymatic digestion followed by magnetic and fluorescence-activated cell sorting.

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Background: Public health strategies in the context of respiratory droplet-transmissible diseases (such as influenza or COVID-19) include intensified hand hygiene promotion, but a review on the effectiveness of different ways of promoting hand hygiene in the community, specifically for this type of infections, has not been performed. This rapid systematic review aims to summarize the effectiveness of community-based hand hygiene promotion programs on infection transmission, health outcomes and behavioral outcomes during epidemic periods in the context of respiratory droplet-transmissible diseases. We also included laboratory-confirmed health outcomes for epidemic-prone disease during interepidemic periods.

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Endothelial cells (ECs) exhibit phenotypic and functional tissue specificities, critical for studies in the vascular field and beyond. Thus, tissue-specific methods for isolation of highly purified ECs are necessary. Kidney, spleen, and testis ECs are relevant players in health and diseases such as chronic kidney disease, acute kidney injury, myelofibrosis, and cancer.

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Endothelial cells (ECs) from the small intestine, colon, liver, and heart have distinct phenotypes and functional adaptations that are dependent on their physiological environment. Gut ECs adapt to low oxygen, heart ECs to contractile forces, and liver ECs to low flow rates. Isolating high-purity ECs in sufficient quantities is crucial to study their functions.

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Background: Drowning is responsible for an estimated 320,000 deaths a year, and over 90% of drowning mortality occurs in low- to middle-income countries (LMICs), with peak drowning rates among children aged 1 to 4 years. In this age group, mortality due to drowning is particularly common in rural settings and about 75% of drowning accidents happen in natural bodies of water close to the home. Providing adequate child supervision can protect children from drowning, and organized formal day care programs could offer a way to achieve this.

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Hepatic fat accumulation is associated with diabetes and hepatocellular carcinoma (HCC). Here, we characterize the metabolic response that high-fat availability elicits in livers before disease development. After a short term on a high-fat diet (HFD), otherwise healthy mice showed elevated hepatic glucose uptake and increased glucose contribution to serine and pyruvate carboxylase activity compared with control diet (CD) mice.

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In this contribution, we present a computational protocol to predict anti-Kasha photoluminescence. The herein developed protocol is based on state-of-the-art quantum chemical calculations and excited-state decay rate theories (i.e.

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Rationale: Endothelial cells (ECs) are highly glycolytic and generate the majority of their energy via the breakdown of glucose to lactate. At the same time, a main role of ECs is to allow the transport of glucose to the surrounding tissues. GLUT1 (glucose transporter isoform 1/) is highly expressed in ECs of the central nervous system (CNS) and is often implicated in blood-brain barrier (BBB) dysfunction, but whether and how GLUT1 controls EC metabolism and function is poorly understood.

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New easily functionalisable and highly fluorescent BOPAHY chromophores are synthesised via a one-pot two-step reaction starting from commercially available pyrrole-2-carbaldehydes and respective acyl hydrazides in the presence of BF·OEt. Most importantly, all BOPAHY dyes show excellent photophysical properties with quantum yields up to 0.92.

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The adsorption of molecular deuterium (D ) onto charged cobalt-fullerene-complexes Co C (n=1-8) is measured experimentally in a few-collision reaction cell. The reactivity is strongly size-dependent, hinting at clustering of the transition metal atoms on the fullerenes. Formation and desorption rate constants are obtained from the pressure-dependent deuterogenation curves.

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The heterogeneity of endothelial cells (ECs) across tissues remains incompletely inventoried. We constructed an atlas of >32,000 single-EC transcriptomes from 11 mouse tissues and identified 78 EC subclusters, including Aqp7 intestinal capillaries and angiogenic ECs in healthy tissues. ECs from brain/testis, liver/spleen, small intestine/colon, and skeletal muscle/heart pairwise expressed partially overlapping marker genes.

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mTORC1 is an important regulator of muscle mass but how it is modulated by oxygen and nutrients is not completely understood. We show that loss of the prolyl hydroxylase domain isoform 1 oxygen sensor in mice (PHD1) reduces muscle mass. PHD1 muscles show impaired mTORC1 activation in response to leucine whereas mTORC1 activation by growth factors or eccentric contractions was preserved.

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Energy metabolism has been repeatedly linked to amyotrophic lateral sclerosis (ALS). Yet, motor neuron (MN) metabolism remains poorly studied and it is unknown if ALS MNs differ metabolically from healthy MNs. To address this question, we first performed a metabolic characterization of induced pluripotent stem cells (iPSCs) versus iPSC-derived MNs and subsequently compared MNs from ALS patients carrying FUS mutations to their CRISPR/Cas9-corrected counterparts.

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Endothelial cells (ECs) form the inner lining of the vascular network. Although they can remain quiescent for years, ECs exhibit high plasticity in both physiological and pathological conditions, when they need to rapidly form new blood vessels in a process called angiogenesis. EC metabolism recently emerged as an important driver of this angiogenic switch.

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The metabolism of endothelial cells (ECs) has only recently been recognized as a driving force of angiogenesis. Metabolic pathways, such as glycolysis, fatty acid oxidation, and glutamine metabolism, have distinct, essential roles during vessel formation. Moreover, EC metabolism is markedly perturbed in pathologies such as cancer and diabetes.

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Abnormal tumor vessels promote metastasis and impair chemotherapy. Hence, tumor vessel normalization (TVN) is emerging as an anti-cancer treatment. Here, we show that tumor endothelial cells (ECs) have a hyper-glycolytic metabolism, shunting intermediates to nucleotide synthesis.

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Cellular proliferation depends on refilling the tricarboxylic acid (TCA) cycle to support biomass production (anaplerosis). The two major anaplerotic pathways in cells are pyruvate conversion to oxaloacetate via pyruvate carboxylase (PC) and glutamine conversion to α-ketoglutarate. Cancers often show an organ-specific reliance on either pathway.

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Aging is associated with progressive white adipose tissue (WAT) enlargement initiated early in life, but the molecular mechanisms involved remain unknown. Here we show that mitochondrial complex IV (CIV) activity and assembly are already repressed in white adipocytes of middle-aged mice and involve a HIF1A-dependent decline of essential CIV components such as COX5B. At the molecular level, HIF1A binds to the Cox5b proximal promoter and represses its expression.

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