150 research outputs found

    Norepinephrine Transporter Blocker Atomoxetine Increases Salivary Alpha Amylase

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    It has been suggested that central norepinephrine (NE) activity may be inferred from increases in salivary alpha-amylase (SAA), but data in favor of this proposition are limited. We administered 40 mg of atomoxetine, a selective NE transporter blocker that increases central NE levels, to 24 healthy adult participants in a double-blind, placebo-controlled cross-over design. Atomoxetine administration significantly increased SAA secretion and concentrations at 75–180 min after treatment (more than doubling baseline levels). Consistent with evidence that elevation in central NE is a co-determinant of hypothalamic-pituitary-adrenal axis activity, salivary cortisol also approximately doubled at the same time points. Moreover, changes in salivary cortisol positively correlated with SAA (0.44 \u3c rho \u3c 0.56), bolstering the position that the origin of the changes in SAA reflect central NE. This work points toward the potential value of SAA as an inexpensive and non-invasive procedure to obtain information about activation of the central NE system

    A new type 2 copper cysteinate azurin: Involvement of an engineered exposed cysteine in copper binding trough internal rearrangement

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    The double mutant H117G/N42C azurin exhibits tetragonal type 2 copper site characteristics with Cys(42) as one of the copper ligands as concluded from spectroscopic evidence (UV-visible, EPR, and resonance Raman). Analysis of the kinetics of copper uptake by the apoprotein by means of stopped flow spectroscopy suggests that the solvent-exposed CyS42 assists in binding the metal ion and carrying it over to the active site where it becomes coordinated by, among others, a second cysteine, Cys(112). A structure is proposed in which the loop from residue 36 to 47 has rearranged to form a tetragonal type 2 copper site with Cys(42) as one of the ligands. The process of copper uptake as observed for the double mutant may be relevant for a better understanding of the way copper chaperones accept and transfer metal ions in the living cell.Macromolecular Biochemistr

    A One-Pot, Whole-Cell Biocatalysis Approach for Vanillin Production using Lignin Oil

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    Vanillin is a popular and versatile flavor compound, almost entirely produced from petroleum-derived phenol by a multi-step chemical synthesis. The process is hazardous to the environment and unsustainable for its fossil oil usage. Therefore, developing environmentally friendly, efficient, and sustainable routes to biobased vanillin is essential. Here, we report on vanillin production from 4-n-propylguaiacol (4PG), one of the main components in lignin oil obtained through reductive catalytic fractionation (RCF) of soft wood, by employing recombinant Escherichia coli cells. Conversion is based on the expression of two engineered oxidative enzymes: a 4-n-propylguaiacol oxidase and an isoeugenol dioxygenase. A high yield of vanillin, 66% from 4PG in RCF lignin oil was achieved through rounds of optimisation of the whole-cell conversion process. This high-performance strategy was readily scaled up to produce vanillin at an unprecedented 18% and 3% yield based on lignin oil and spruce wood respectively. The whole-cell bioconversion process shows good tolerance even at high loadings of starting material, showcasing the robustness and applicability of the employed biocatalysts. This work paves the way for further development towards the efficient production of high-titer biobased vanillin using depolymerised lignin as the feedstock.</p

    The burden of varicella from a parent's perspective and its societal impact in The Netherlands: an Internet survey

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    <p>Abstract</p> <p>Background</p> <p>Varicella is a common childhood disease. Only 5% of first varicella-zoster-virus infections occur asymptomatically. Most data on the burden of varicella stem from health service databases. This study aims to provide insight in the burden of varicella from a parent's perspective including cases outside the healthcare system.</p> <p>Methods</p> <p>An internet questionnaire was developed for parents in the Netherlands to report health care resource use and productivity losses during the varicella episode in their child younger than 6 years. 11,367 invitations were sent out to members with children of an internet panel of a market research agency. 4,168 (37%) parents started the questionnaire (response rate), of which 360 (9%) stopped before completion and 1,838 (44%) were out of the target group. In total 1,970 parents completed the questionnaire. The questionnaire provided a symptom list ranging from common symptoms, such as skin vesicles, itching to fits or convulsions. A posteriori, in the analyses, the symptoms 'skin infections', 'fits/convulsions', 'unconsciousness', and 'balance and movement disorders' were labelled as complications. There was no restriction to time since the varicella episode for inclusion in the analyses.</p> <p>Results</p> <p>The 1,970 respondents had in total 2,899 children aged younger than six years, of which 2,564 (88%) children had had varicella. In 62% of the episodes the parent did not seek medical help. In 18% of all episodes symptoms labelled as complications were reported; in 11% of all episodes parents visited a medical doctor (MD) for a complication. Reporting of complications did not differ (X<sup>2 </sup>; p = 0.964) between children with a recent (≤ 12 months ago) or a more distant (> 12 months) history of varicella. Prescription drugs were used in 12% of the children with varicella; OTC drugs in 72%. Parents reported work loss in 17% of the varicella-episodes (23% when MD visit; 14% when no MD-visit) for on average 14 hours, which equals to 2.5 hours of work loss for any given varicella-episode.</p> <p>Conclusions</p> <p>This study shows the full spectrum of varicella-episodes and associated healthcare use, including the large proportion of cases not seeking medical care and the societal impact associated with those cases.</p

    Human kidney organoids produce functional renin

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    Renin production by the kidney is of vital importance for salt, volume, and blood pressure homeostasis. The lack of human models hampers investigation into the regulation of renin and its relevance for kidney physiology. To develop such a model, we used human induced pluripotent stem cell–derived kidney organoids to study the role of renin and the renin-angiotensin system in the kidney. Extensive characterization of the kidney organoids revealed kidney-specific cell populations consisting of podocytes, proximal and distal tubular cells, stromal cells and endothelial cells. We examined the presence of various components of the renin-angiotensin system such as angiotensin II receptors, angiotensinogen, and angiotensin-converting enzymes 1 and 2. We identified by single-cell sequencing, immunohistochemistry, and functional assays that cyclic AMP stimulation induces a subset of pericytes to increase the synthesis and secretion of enzymatically active renin. Renin production by the organoids was responsive to regulation by parathyroid hormone. Subcutaneously implanted kidney organoids in immunodeficient IL2Ry-/-Rag2-/- mice were successfully vascularized, maintained tubular and glomerular structures, and retained capacity to produce renin two months after implantation. Thus, our results demonstrate that kidney organoids express renin and provide insights into the endocrine potential of human kidney organoids, which is important for regenerative medicine in the context of the endocrine system

    Design of TLR2-ligand-synthetic long peptide conjugates for therapeutic vaccination of chronic HBV patients

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    Synthetic long peptide (SLP) vaccination is a promising new treatment strategy for patients with a chronic hepatitis B virus (HBV) infection. We have previously shown that a prototype HBV-core protein derived SLP was capable of boosting CD4+ and CD8+ T cell responses in the presence of a TLR2-ligand in chronic HBV patients ex vivo. For optimal efficacy of a therapeutic vaccine in vivo, adjuvants can be conjugated to the SLP to ensure delivery of both the antigen and the co-stimulatory signal to the same antigen-presenting cell (APC). Dendritic cells (DCs) express the receptor for the adjuvant and are optimally equipped to efficiently process and present the SLP-contained epitopes to T cells. Here, we investigated TLR2-ligand conjugation of the prototype HBV-core SLP. Results indicated that TLR2-ligand conjugation reduced cross-presentation efficiency of the SLP-contained epitope by both monocyte-derived and naturally occurring DC subsets. Importantly, cross-presentation was improved after optimization of the conjugate by either shortening the SLP or by placing a valine-citrulline linker between the TLR2-ligand and the long SLP, to facilitate endosomal dissociation of SLP and TLR2-ligand after uptake. HBV-core SLP conjugates also triggered functional patient T cell responses ex vivo. These results provide an import step forward in the design of a therapeutic SLP-based vaccine to cure chronic HBV

    Interactions of the Immune System with Human Kidney Organoids

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    Kidney organoids are an innovative tool in transplantation research. The aim of the present study was to investigate whether kidney organoids are susceptible for allo-immune attack and whether they can be used as a model to study allo-immunity in kidney transplantation. Human induced pluripotent stem cell-derived kidney organoids were co-cultured with human peripheral blood mononuclear cells (PBMC), which resulted in invasion of allogeneic T-cells around nephron structures and macrophages in the stromal cell compartment of the organoids. This process was associated with the induction of fibrosis. Subcutaneous implantation of kidney organoids in immune-deficient mice followed by adoptive transfer of human PBMC led to the invasion of diverse T-cell subsets. Single cell transcriptomic analysis revealed that stromal cells in the organoids upregulated expression of immune response genes upon immune cell invasion. Moreover, immune regulatory PD-L1 protein was elevated in epithelial cells while genes related to nephron differentiation and function were downregulated. This study characterized the interaction between immune cells and kidney organoids, which will advance the use of kidney organoids for transplantation research

    Clinical complexity and impact of the ABC (Atrial fibrillation Better Care) pathway in patients with atrial fibrillation: a report from the ESC-EHRA EURObservational Research Programme in AF General Long-Term Registry

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    Background: Clinical complexity is increasingly prevalent among patients with atrial fibrillation (AF). The ‘Atrial fibrillation Better Care’ (ABC) pathway approach has been proposed to streamline a more holistic and integrated approach to AF care; however, there are limited data on its usefulness among clinically complex patients. We aim to determine the impact of ABC pathway in a contemporary cohort of clinically complex AF patients. Methods: From the ESC-EHRA EORP-AF General Long-Term Registry, we analysed clinically complex AF patients, defined as the presence of frailty, multimorbidity and/or polypharmacy. A K-medoids cluster analysis was performed to identify different groups of clinical complexity. The impact of an ABC-adherent approach on major outcomes was analysed through Cox-regression analyses and delay of event (DoE) analyses. Results: Among 9966 AF patients included, 8289 (83.1%) were clinically complex. Adherence to the ABC pathway in the clinically complex group reduced the risk of all-cause death (adjusted HR [aHR]: 0.72, 95%CI 0.58–0.91), major adverse cardiovascular events (MACEs; aHR: 0.68, 95%CI 0.52–0.87) and composite outcome (aHR: 0.70, 95%CI: 0.58–0.85). Adherence to the ABC pathway was associated with a significant reduction in the risk of death (aHR: 0.74, 95%CI 0.56–0.98) and composite outcome (aHR: 0.76, 95%CI 0.60–0.96) also in the high-complexity cluster; similar trends were observed for MACEs. In DoE analyses, an ABC-adherent approach resulted in significant gains in event-free survival for all the outcomes investigated in clinically complex patients. Based on absolute risk reduction at 1 year of follow-up, the number needed to treat for ABC pathway adherence was 24 for all-cause death, 31 for MACEs and 20 for the composite outcome. Conclusions: An ABC-adherent approach reduces the risk of major outcomes in clinically complex AF patients. Ensuring adherence to the ABC pathway is essential to improve clinical outcomes among clinically complex AF patients

    Impact of renal impairment on atrial fibrillation: ESC-EHRA EORP-AF Long-Term General Registry

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    Background: Atrial fibrillation (AF) and renal impairment share a bidirectional relationship with important pathophysiological interactions. We evaluated the impact of renal impairment in a contemporary cohort of patients with AF. Methods: We utilised the ESC-EHRA EORP-AF Long-Term General Registry. Outcomes were analysed according to renal function by CKD-EPI equation. The primary endpoint was a composite of thromboembolism, major bleeding, acute coronary syndrome and all-cause death. Secondary endpoints were each of these separately including ischaemic stroke, haemorrhagic event, intracranial haemorrhage, cardiovascular death and hospital admission. Results: A total of 9306 patients were included. The distribution of patients with no, mild, moderate and severe renal impairment at baseline were 16.9%, 49.3%, 30% and 3.8%, respectively. AF patients with impaired renal function were older, more likely to be females, had worse cardiac imaging parameters and multiple comorbidities. Among patients with an indication for anticoagulation, prescription of these agents was reduced in those with severe renal impairment, p&nbsp;&lt;.001. Over 24&nbsp;months, impaired renal function was associated with significantly greater incidence of the primary composite outcome and all secondary outcomes. Multivariable Cox regression analysis demonstrated an inverse relationship between eGFR and the primary outcome (HR 1.07 [95% CI, 1.01–1.14] per 10&nbsp;ml/min/1.73&nbsp;m2 decrease), that was most notable in patients with eGFR &lt;30&nbsp;ml/min/1.73&nbsp;m2 (HR 2.21 [95% CI, 1.23–3.99] compared to eGFR ≥90&nbsp;ml/min/1.73&nbsp;m2). Conclusion: A significant proportion of patients with AF suffer from concomitant renal impairment which impacts their overall management. Furthermore, renal impairment is an independent predictor of major adverse events including thromboembolism, major bleeding, acute coronary syndrome and all-cause death in patients with AF
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