23 results on '"Kuipers H"'
Search Results
2. Value of routine intraoperative frozen sections of proximal bile duct margins in perihilar cholangiocarcinoma, a retrospective multicenter and matched case-control study
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Nooijen, L. E., Franken, L. C., de Boer, M. T., Buttner, S., van Dieren, S., Koerkamp, B. Groot, Hoogwater, F. J.H., Kazemier, G., Klümpen, H. J., Kuipers, H., Olthof, P. B., Swijnenburg, R. J., Verheij, J., Zonderhuis, B. M., van Gulik, T. M., Erdmann, J. I., Nooijen, L. E., Franken, L. C., de Boer, M. T., Buttner, S., van Dieren, S., Koerkamp, B. Groot, Hoogwater, F. J.H., Kazemier, G., Klümpen, H. J., Kuipers, H., Olthof, P. B., Swijnenburg, R. J., Verheij, J., Zonderhuis, B. M., van Gulik, T. M., and Erdmann, J. I.
- Abstract
Background: Currently, the potential benefits of additional resection after positive proximal intraoperative frozen sections (IFS) in perihilar cholangiocarcinoma (pCCA) on residual disease and oncological outcome remain uncertain. Therefore, the aim of this study is to investigate the number of R0 resections after additional resection of a positive proximal IFS and the influence of additional resections on overall survival (OS) in patients with pCCA. Materials and methods: A retrospective, multicenter, matched case-control study was performed, including patients undergoing resection for pCCA between 2000 and 2019 at three tertiary centers. Primary outcome was the number of achieved ‘additional’ R0 resections. Secondary outcomes were OS, recurrence, severe morbidity and mortality. Results: Forty-four out of 328 patients undergoing resection for pCCA had a positive proximal IFS. An additional resection was performed in 35 out of 44 (79.5%) patients, which was negative in 24 (68.6%) patients. Nevertheless, seven out of these 24 patients were eventually classified as R1 resection due to other positive resection margins. Therefore, 17 (48.6%) patients could be classified as “true” R0 resection after additional resection. Ninety-day mortality after R1 resections was high (25%) and strongly influenced OS. After correction for 90-day mortality, median OS after negative additional resection was 33 months (95%CI:29.5–36.5) compared to 30 months (95%CI:24.4–35.6) after initial R1 (P = 0.875) and 46 months (95%CI:32.7–59.3) after initial R0 (P = 0.348). Conclusion: There were only 17 patients (out of a total of 328 patients) that potentially benefitted from routine IFS. Additional resection for a positive IFS leading to R0 resection was not associated with improved long-term survival.
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- 2022
3. The Association Between Loneliness and Psychiatric Symptomatology in Older Psychiatric Outpatients
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Schutter, N., Holwerda, T.J., Kuipers, H., Van, R.H.L., Stek, M.L., Comijs, H.C., Peen, J., Dekker, J.J.M., Schutter, N., Holwerda, T.J., Kuipers, H., Van, R.H.L., Stek, M.L., Comijs, H.C., Peen, J., and Dekker, J.J.M.
- Abstract
Purpose: Loneliness in adults increases with age. Although loneliness has been found to be associated with psychiatric disorders and dementia, no information is available on prevalence of loneliness in older psychiatric patients. The aims of this study were to examine prevalence of loneliness in older psychiatric outpatients, including gender differences and associations with psychiatric disorders and social isolation. Methods: Cross-sectional study in an outpatient clinic for geriatric psychiatry between September 2013 and February 2018. Interviews were done in 181 patients. Results: 80% of participants were lonely. Loneliness was associated with having contacts in less social network domains, in women but not in men. There were no associations with DSM-IV-TR-classifications. However, loneliness was associated with higher scores on questionnaires for depression and cognitive function. Intensity of treatment did not differ significantly between lonely and non-lonely participants. Conclusion: Loneliness is highly prevalent in older psychiatric outpatients, with men and women equally affected. Loneliness should be assessed in all older psychiatric patients, especially when they show high scores on symptom checklists or have a restricted social network.
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- 2022
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4. Liver Transplantation for Unresectable Perihilar Cholangiocarcinoma: Is Neo-Adjuvant Chemo-Radiation Therapy Really Necessary? An International, Multicenter Comparison
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Hoogwater, F.J., primary, Kuipers, H., additional, de Meijer, V.E., additional, Maulat, C., additional, Muscari, F., additional, Polak, W.G., additional, van Hoek, B., additional, Jézéquel, C., additional, Alwayn, I.P., additional, IJzermans, J.N., additional, Mohkam, K., additional, Mabrut, J.-Y., additional, van Vilsteren, F.G., additional, Adam, J.-P., additional, Chiche, L., additional, Chebaro, A., additional, Boleslawski, E., additional, Dubbeld, J., additional, Darwish Murad, S., additional, Rayar, M., additional, and Porte, R.J., additional
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- 2022
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5. Gallbladder Cancer: Current Insights in Genetic Alterations and their Possible Therapeutic Implications
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Kuipers, H., primary, de Bitter, T.J., additional, Fehrmann, R.S., additional, van der Post, R.S., additional, Nijkamp, M.W., additional, de Reuver, P.R., additional, de Boer, M.T., additional, and Hoogwater, F.J., additional
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- 2022
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6. YAP-TEAD inhibition is associated with upregulation of an androgen receptor mediated transcription program providing therapeutic escape.
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Alva-Ruiz R, Watkins RD, Tomlinson JL, Yonkus JA, Abdelrahman AM, Conboy CB, Jessen E, Werneburg NW, Kuipers H, Sample JW, Gores GJ, Ilyas SI, Truty MJ, and Smoot RL
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- Humans, Animals, Mice, Up-Regulation drug effects, Cell Line, Tumor, TEA Domain Transcription Factors metabolism, Gene Expression Regulation, Neoplastic drug effects, Xenograft Model Antitumor Assays, Adaptor Proteins, Signal Transducing metabolism, Adaptor Proteins, Signal Transducing genetics, Receptors, Androgen metabolism, Receptors, Androgen genetics, YAP-Signaling Proteins metabolism, YAP-Signaling Proteins genetics, Transcription Factors metabolism, Transcription Factors genetics
- Abstract
Cholangiocarcinoma (CCA) is a highly aggressive form of liver cancer and is an increasing cause of cancer-related death worldwide. Despite its increasing incidence globally and alarming mortality, treatment options for CCA have largely remained unchanged, stressing the importance of developing new effective therapies. YAP activation is common in CCA, and its major transcriptional signaling partners are the TEAD proteins. CA3 is a small-molecule YAP-TEAD disrupter discovered utilizing a TEAD reporter assay. Utilizing CCA, gastric cancer cell lines, and patient-derived xenograft models (PDX), we demonstrate that CA3 is effective in inducing cell death and delaying tumor growth in both FGFR2 fusion and wild-type models. CA3 was associated with on-target decreases in YAP-TEAD target gene expression, TEAD reporter activity, and overall TEAD levels. Hippo pathway signaling was not altered as there was no change in YAP phosphorylation status in the cells exposed to CA3. RNA sequencing of gastric cancer and CCA models demonstrated upregulation of an androgen receptor-mediated transcriptional program following exposure to CA3 in five unique models tested. Consistent with this upstream regulator analysis, CA3 exposure in CCA cells was associated with increased AR protein levels, and combinatorial therapy with CA3 and androgen receptor blockade was associated with increased cancer cell death. CA3 behaves functionally as a YAP-TEAD disrupter in the models tested and demonstrated therapeutic efficacy. Exposure to CA3 was associated with compensatory androgen receptor signaling and dual inhibition improved the therapeutic effect., (© 2024 The Author(s). FEBS Open Bio published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)
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- 2024
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7. Primary cilia signaling in astrocytes mediates development and regional-specific functional specification.
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Wang L, Guo Q, Acharya S, Zheng X, Huynh V, Whitmore B, Yimit A, Malhotra M, Chatterji S, Rosin N, Labit E, Chipak C, Gorzo K, Haidey J, Elliott DA, Ram T, Zhang Q, Kuipers H, Gordon G, Biernaskie J, and Guo J
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- Animals, Mice, Brain metabolism, Brain growth & development, Neurogenesis physiology, Mice, Inbred C57BL, Male, Cilia metabolism, Cilia physiology, Astrocytes metabolism, Signal Transduction physiology, Hedgehog Proteins metabolism, Hedgehog Proteins genetics
- Abstract
Astrocyte diversity is greatly influenced by local environmental modulation. Here we report that the majority of astrocytes across the mouse brain possess a singular primary cilium localized to the cell soma. Comparative single-cell transcriptomics reveals that primary cilia mediate canonical SHH signaling to modulate astrocyte subtype-specific core features in synaptic regulation, intracellular transport, energy and metabolism. Independent of canonical SHH signaling, primary cilia are important regulators of astrocyte morphology and intracellular signaling balance. Dendritic spine analysis and transcriptomics reveal that perturbation of astrocytic cilia leads to disruption of neuronal development and global intercellular connectomes in the brain. Mice with primary ciliary-deficient astrocytes show behavioral deficits in sensorimotor function, sociability, learning and memory. Our results uncover a critical role for primary cilia in transmitting local cues that drive the region-specific diversification of astrocytes within the developing brain., (© 2024. The Author(s), under exclusive licence to Springer Nature America, Inc.)
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- 2024
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8. Protein-losing enteropathy as a result of colon polyposis and colon cancer: a multidisciplinary approach to diagnosis and treatment.
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Kuipers H, van Westreenen HL, Moll FCP, and de Vos Tot Nederveen Cappel WH
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- Humans, Male, Middle Aged, Colonic Polyps surgery, Colonic Polyps complications, Colonic Polyps diagnosis, Colonoscopy, Tomography, X-Ray Computed, Protein-Losing Enteropathies etiology, Protein-Losing Enteropathies diagnosis, Protein-Losing Enteropathies therapy, Colonic Neoplasms complications, Colonic Neoplasms diagnosis, Colonic Neoplasms surgery, Colectomy
- Abstract
A man in his 60s presented to our emergency department with severe peripheral pitting oedema, weight gain, dyspnoea and diarrhoea. Blood tests showed a hypoalbuminaemia of 15 g/L. A suspicion of protein-losing enteropathy arose after the exclusion of albuminuria, cardiac failure, protein deficiency and liver cirrhosis. An abdominal CT scan revealed a wall thickening of the colon, and a subsequent colonoscopy identified multiple large obstructive polyps in the ascending colon. The patient underwent a right hemicolectomy which revealed the presence of tubulovillous polyps and a pT2N0 colon carcinoma. Following surgery, the patient experienced clinical improvement with normalisation of serum albumin and resolution of the oedema.Protein-losing enteropathy should be considered an underlying syndrome in patients with peripheral oedema and hypoalbuminaemia in the absence of cardiac failure, proteinuria, malnutrition and hepatic disease. This diagnostic process requires a multidisciplinary approach. For adequate treatment, the primary cause of protein-losing enteropathy needs to be investigated., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2024. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2024
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9. Syngeneic murine models with distinct immune microenvironments represent subsets of human intrahepatic cholangiocarcinoma.
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Tomlinson JL, Li B, Yang J, Loeuillard E, Stumpf HE, Kuipers H, Watkins R, Carlson DM, Willhite J, O'Brien DR, Graham RP, Chen X, Smoot RL, Dong H, Gores GJ, and Ilyas SI
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- Animals, Mice, Humans, F-Box-WD Repeat-Containing Protein 7 genetics, Cell Line, Tumor, Cholangiocarcinoma immunology, Cholangiocarcinoma genetics, Tumor Microenvironment immunology, Bile Duct Neoplasms immunology, Bile Duct Neoplasms genetics, Disease Models, Animal
- Abstract
Background & Aims: Cholangiocarcinoma (CCA) is a poorly immunogenic malignancy associated with limited survival. Syngeneic immunocompetent mouse models of CCA are an essential tool to elucidate the tumor immune microenvironment (TIME), understand mechanisms of tumor immune evasion, and test novel immunotherapeutic strategies. The scope of this study was to develop and characterize immunocompetent CCA models with distinct genetic drivers, and correlate tumor genomics, immunobiology, and therapeutic response., Methods: A multifaceted approach including scRNA-seq, CITE-seq, whole exome and bulk RNA sequencing was employed. FDA-approved PD-1/PD-L1 antibodies were tested in humanized PD-1/PD-L1 mice (HuPD-H1)., Results: A genetic mouse model of intrahepatic CCA (iCCA) driven by intrabiliary transduction of Fbxw7ΔF/Akt that mimics human iCCA was generated. From the Fbxw7ΔF/Akt tumors, a murine cell line (FAC) and syngeneic model with genetic and phenotypic characteristics of human iCCA were developed. Established SB1 (YAP
S127A /Akt) and KPPC (KrasG12D p53L/L ) models were compared to the FAC model. Although the models had transcriptomic similarities, they had substantial differences as well. Mutation patterns of FAC, SB1, and KPPC cells matched different mutational signatures in Western and Japanese CCA patient cohorts. KPPC tumors had a high tumor mutation burden. FAC tumors had a T cell-infiltrated TIME, while SB1 tumors had a preponderance of suppressive myeloid cells. FAC, SB1, and KPPC tumors matched different immune signatures in human iCCA cohorts. Moreover, FAC, SB1, and KPPC tumor-bearing HuPD-H1 mice displayed differential responses to nivolumab or durvalumab., Conclusions: Syngeneic iCCA models display a correlation between tumor genotype and TIME phenotype, with differential responses to FDA-approved immunotherapies. This study underscores the importance of leveraging multiple preclinical models to understand responses to immunotherapy in different genetic subsets of human CCA., Impact and Implications: Understanding the relationship between tumor genotype and the phenotype of the immune microenvironment is an unmet need in cholangiocarcinoma (CCA). Herein, we use syngeneic murine models of intrahepatic CCA with different genetic drivers to demonstrate a correlation between tumor genotype and immune microenvironment phenotype in murine models, which is associated with differential responses to FDA-approved immunotherapies. This information will help guide other preclinical studies. Additionally, it emphasizes that immune checkpoint inhibition in patients with CCA is not a "one-size-fits-all" approach. Our observations suggest that, as for targeted therapies, patients should be stratified and selected for treatment according to their tumor genetics., (Copyright © 2024 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)- Published
- 2024
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10. Performance and microbial community composition of full-scale high-rate cascade sludge digestion system via pie-shaped reactor configuration.
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Guo H, McIntyre M, Visser A, Kuipers H, van Lier JB, and de Kreuk M
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- Hydrolysis, Biological Oxygen Demand Analysis, Anaerobiosis, Archaea metabolism, Archaea genetics, Sewage microbiology, Bioreactors microbiology
- Abstract
A full-scale high-rate cascade anaerobic digestion (CAD) system was evaluated for its ability to enhance enzymatic sludge hydrolysis. The system included a newly built digester, innovatively divided into three pie-shaped compartments (500 m
3 each), followed by an existing, larger digester (1500 m3 ). The system treated a mixture of waste activated sludge and primary sludge, achieving a stable total chemical oxygen demand reduction efficiency (56.1 ± 6.8 %), and enhanced sludge hydrolytic enzyme activities at a 14.5-day total solids retention time (SRT). High-throughput sequencing data revealed a consistent microbial community across reactors, dominated by consortia that govern hydrolysis and acidogenesis. Despite relatively short SRTs in the initial reactors of the CAD system, acetoclastic methanogens belonging to Methanosaeta became the most abundant archaea. This study proves that the CAD system achieves stable sludge reduction, accelerates enzymatic hydrolysis at full-scale, and paves the way for its industrialization in municipal waste sewage sludge treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)- Published
- 2024
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11. Development of an in vitro setup for flow studies in a stented carotid artery bifurcation.
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Hoving AM, Mikhal J, Kuipers H, de Borst GJ, and Slump CH
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- Humans, Rheology methods, Pulsatile Flow physiology, Stents, Blood Flow Velocity physiology, Carotid Arteries physiology, Hemodynamics
- Abstract
To investigate flow conditions in a double-layered carotid artery stent, a bench-top in vitro flow setup including a bifurcation phantom was designed and fabricated. The geometry of the tissue-mimicking phantom was based on healthy individuals. Two identical phantoms were created using 3D-printing techniques and molding with PVA-gel. In one of them, a clinically available CGuard double-layer stent was inserted. Measurements were performed using both continuous and pulsatile flow conditions. Blood flow studies were performed using echoPIV: a novel ultrasound-based technique combined with particle image velocimetry. A maximum deviation of 3% was visible between desired and measured flow patterns. The echoPIV measurements showed promising results on visualization and quantification of blood flow in and downstream the stent. Further research could demonstrate the effects of a double-layered stent on blood flow patterns in a carotid bifurcation in detail., (© 2023. International Federation for Medical and Biological Engineering.)
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- 2024
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12. Impact of SARS-CoV-2 spike stability and RBD exposure on antigenicity and immunogenicity.
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Rutten L, Swart M, Koornneef A, Bouchier P, Blokland S, Sadi A, Juraszek J, Vijayan A, Schmit-Tillemans S, Verspuij J, Choi Y, Daal CE, Perkasa A, Torres Morales S, Myeni SK, Kikkert M, Tolboom J, van Manen D, Kuipers H, Schuitemaker H, Zahn R, and Langedijk JPM
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- Mice, Humans, Animals, SARS-CoV-2, COVID-19 Vaccines, Antibodies, Viral, Spike Glycoprotein, Coronavirus metabolism, Antibodies, Neutralizing, COVID-19 prevention & control, Viral Vaccines
- Abstract
The spike protein (S) of SARS-CoV-2 induces neutralizing antibodies and is the key component of current COVID-19 vaccines. The most efficacious COVID-19 vaccines are genetically-encoded spikes with a double proline substitution in the hinge region to stabilize S in the prefusion conformation (S-2P). A subunit vaccine can be a valuable addition to mRNA and viral vector-based vaccines but requires high stability of spike. In addition, further stabilization of the prefusion conformation of spike might improve immunogenicity. To test this, five spike proteins were designed and characterized, ranging from low to high stability. The immunogenicity of these proteins was assessed in mice, demonstrating that a spike (S-closed-2) with a high melting temperature, which still allowed ACE2 binding, induced the highest neutralization titers against homologous and heterologous strains (up to 16-fold higher than the least stabilized spike). In contrast, the most stable spike variant (S-locked), in which the receptor binding domains (RBDs) were locked in a closed conformation and thus not able to breathe, induced relatively low neutralizing antibody titers against heterologous strains. These data demonstrate that S protein stabilization with RBDs exposing highly conserved epitopes may be needed to increase the immunogenicity of spike proteins for future COVID-19 vaccines., (© 2024. The Author(s).)
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- 2024
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13. Enhancing breadth and durability of humoral immune responses in non-human primates with an adjuvanted group 1 influenza hemagglutinin stem antigen.
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Swart M, Kuipers H, Milder F, Jongeneelen M, Ritschel T, Tolboom J, Muchene L, van der Lubbe J, Izquierdo Gil A, Veldman D, Huizingh J, Verspuij J, Schmit-Tillemans S, Blokland S, de Man M, Roozendaal R, Fox CB, Schuitemaker H, Capelle M, Langedijk JPM, Zahn R, and Brandenburg B
- Abstract
Seasonal influenza vaccines must be updated annually and suboptimally protect against strains mismatched to the selected vaccine strains. We previously developed a subunit vaccine antigen consisting of a stabilized trimeric influenza A group 1 hemagglutinin (H1) stem protein that elicits broadly neutralizing antibodies. Here, we further optimized the stability and manufacturability of the H1 stem antigen (H1 stem v2, also known as INFLUENZA G1 mHA) and characterized its formulation and potency with different adjuvants in vitro and in animal models. The recombinant H1 stem antigen (50 µg) was administered to influenza-naïve non-human primates either with aluminum hydroxide [Al(OH)
3 ] + NaCl, AS01B , or SLA-LSQ formulations at week 0, 8 and 34. These SLA-LSQ formulations comprised of varying ratios of the synthetic TLR4 agonist 'second generation synthetic lipid adjuvant' (SLA) with liposomal QS-21 (LSQ). A vaccine formulation with aluminum hydroxide or SLA-LSQ (starting at a 10:25 µg ratio) induced HA-specific antibodies and breadth of neutralization against a panel of influenza A group 1 pseudoviruses, comparable with vaccine formulated with AS01B , four weeks after the second immunization. A formulation with SLA-LSQ in a 5:2 μg ratio contained larger fused or aggregated liposomes and induced significantly lower humoral responses. Broadly HA stem-binding antibodies were detectable for the entire period after the second vaccine dose up to week 34, after which they were boosted by a third vaccine dose. These findings inform about potential adjuvant formulations in clinical trials with an H1 stem-based vaccine candidate., (© 2023. The Author(s).)- Published
- 2023
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14. The influence of electrocardiogram-gated computed tomography reconstruction into 8 or 10 cardiac phases on cardiac-pulsatility-induced motion quantification of stent grafts in the aorta.
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Simmering JA, Zagers DA, Geelkerken RH, Kuipers H, Te Riet O G Scholten GA, Reijnen MMPJ, and Slump CH
- Abstract
Objective: The goal of this study was to determine to what extent aortic stent graft motion quantification is comparable between electrocardiogram (ECG)-gated computed tomography (CT) scans with reconstructions into 8 and 10 cardiac phases on CT scanners from two different vendors., Methods: An experimental setup that induces motion of an aortic stent graft, according to a predefined aortic blood pressure wave, was placed in two CT scanners of different vendors. The stent graft motion was captured using an ECG-gated CT technique and quantified using dedicated analysis algorithms. The calculated motion amplitudes and total traveled path lengths of stent segmentations were compared between scans reconstructed into 8 and 10 phases and between the scanners, after validation with sensor measurements and repeated measurements., Results: No difference in motion amplitudes in z-direction (craniocaudal direction) was observed between the reconstructions into 8 and 10 phases (0.02 mm; 95% confidence interval [CI], -0.01 to 0.05 mm; P = .358). The z-amplitudes differed by 0.04 mm (95% CI, 0.01-0.07 mm; P = .003) between the different CT scanners. Path lengths differed 0.07 mm (95% CI, 0.01-to 0.13 mm; P = .013) between the reconstructions into 8 and 10 phases and 0.13 mm (95% CI, 0.06-0.17 mm; P < .001) between the different scanners., Conclusions: The motion amplitudes can accurately be compared between 8 and 10 phases and between the two scanners, without differences larger than the voxel size of 0.3 × 0.3 × 0.5 mm. Clinical motion analysis results of different ECG-gated CT scans and CT scanners can be compared up to the accuracy of the CT scan., Competing Interests: M.R. is a consultant for W. L. Gore & Associates., (© 2023 by the Society for Vascular Surgery. Published by Elsevier Inc.)
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- 2023
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15. Factors influencing the downstream passage of European silver eels (Anguilla anguilla) through a tidal sluice.
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Huisman JBJ, Höhne L, Hanel R, Kuipers H, Schollema PP, and Nagelkerke L
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- Animals, Animal Migration, Endangered Species, Rivers, Water, Anguilla
- Abstract
Tidal sluices are a frequent element in the tidal regions of Europe's rivers and may hinder downstream migrating European eels Anguilla anguilla. Sea level rise will reduce the possibility for tidal sluices to freely discharge water, further compressing windows of opportunity for the passage of eels. Understanding how eels utilize the discharge events of tidal sluices and which conditions facilitate successful passage is pivotal for the design of effective fish migration measures. To investigate eel migration at a tidal sluice, acoustic receivers were placed at the tidal sluice Nieuwe Statenzijl and in its tributary of the Westerwoldse Aa, the Netherlands. Of the 30 tagged eels, 26 eels reached the tidal sluice and passage success was 100%. The mean migration speed of eels in the unobstructed part of the tributary was slow (0.14 m s
-1 ). The eels were delayed in their migration by the sluice and delay was right-skewed distributed with most eels showing moderate delays (<2 days), while about 10% of the tagged individuals experienced extensive delays of more than 3 weeks. The number of missed sluicing events prior to successful passage was influenced by biological characteristics such as migration speed in the tributary, weight and condition. In addition, sluicing events with rapidly increasing and high maximum discharge levels increased the success rate of an individual eel to pass the sluice. Compromising sluicing duration in favour of higher and faster increasing discharge could facilitate eel migration at tidal barriers and contribute to the recovery of this endangered species., (© 2023 The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of Fisheries Society of the British Isles.)- Published
- 2023
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16. Booster vaccination with Ad26.COV2.S or an Omicron-adapted vaccine in pre-immune hamsters protects against Omicron BA.2.
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Swart M, van der Lubbe J, Schmit-Tillemans S, van Huizen E, Verspuij J, Gil AI, Choi Y, Daal C, Perkasa A, de Wilde A, Claassen E, de Jong R, Wiese KE, Cornelissen L, van Es M, van Heerden M, Kourkouta E, Tahiri I, Mulders M, Vreugdenhil J, Feddes-de Boer K, Muchene L, Tolboom J, Dekking L, Juraszek J, Vellinga J, Custers J, Bos R, Schuitemaker H, Wegmann F, Roozendaal R, Kuipers H, and Zahn R
- Abstract
Since the original outbreak of the SARS-CoV-2 virus, several rapidly spreading SARS-CoV-2 variants of concern (VOC) have emerged. Here, we show that a single dose of Ad26.COV2.S (based on the Wuhan-Hu-1 spike variant) protects against the Gamma and Delta variants in naive hamsters, supporting the observed maintained vaccine efficacy in humans against these VOC. Adapted spike-based booster vaccines targeting Omicron variants have now been authorized in the absence of human efficacy data. We evaluated the immunogenicity and efficacy of Ad26.COV2.S.529 (encoding a stabilized Omicron BA.1 spike) in naive mice and in hamsters with pre-existing immunity to the Wuhan-Hu-1 spike. In naive mice, Ad26.COV2.S.529 elicited higher neutralizing antibody titers against SARS-CoV-2 Omicron BA.1 and BA.2, compared with Ad26.COV2.S. However, neutralizing titers against the SARS-CoV-2 B.1 (D614G) and Delta variants were lower after primary vaccination with Ad26.COV2.S.529 compared with Ad26.COV2.S. In contrast, we found comparable Omicron BA.1 and BA.2 neutralizing titers in hamsters with pre-existing Wuhan-Hu-1 spike immunity after vaccination with Ad26.COV2.S, Ad26.COV2.S.529 or a combination of the two vaccines. Moreover, all three vaccine modalities induced equivalent protection against Omicron BA.2 challenge in these animals. Overall, our data suggest that an Omicron BA.1-based booster in rodents does not improve immunogenicity and efficacy against Omicron BA.2 over an Ad26.COV2.S booster in a setting of pre-existing immunity to SARS-CoV-2., (© 2023. The Author(s).)
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- 2023
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17. Role of neoadjuvant chemoradiotherapy in liver transplantation for unresectable perihilar cholangiocarcinoma: multicentre, retrospective cohort study.
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Hoogwater FJH, Kuipers H, de Meijer VE, Maulat C, Muscari F, Polak WG, van Hoek B, Jézéquel C, Alwayn IPJ, Ijzermans JNM, Mohkam K, Mabrut JY, Van Vilsteren FGI, Adam JP, Chiche L, Chebaro A, Boleslawski E, Dubbeld J, Murad SD, Rayar M, and Porte RJ
- Subjects
- Humans, Neoadjuvant Therapy, Neoplasm Recurrence, Local pathology, Retrospective Studies, Bile Ducts, Intrahepatic pathology, Klatskin Tumor surgery, Klatskin Tumor pathology, Liver Transplantation, Cholangiocarcinoma, Bile Duct Neoplasms
- Abstract
Background: The Mayo protocol for liver transplantation in patients with unresectable perihilar cholangiocarcinoma is based on strict selection and neoadjuvant chemoradiotherapy. The role of neoadjuvant chemoradiotherapy in this scenario remains unclear. The aim of this study was to compare outcomes after transplantation for perihilar cholangiocarcinoma using strict selection criteria, either with or without neoadjuvant chemoradiotherapy., Methods: This was an international, multicentre, retrospective cohort study of patients who underwent transplantation between 2011 and 2020 for unresectable perihilar cholangiocarcinoma using the Mayo selection criteria and receiving neoadjuvant chemoradiotherapy or not receiving neoadjuvant chemoradiotherapy. Endpoints were post-transplant survival, post-transplant morbidity rate, and time to recurrence., Results: Of 49 patients who underwent liver transplantation for perihilar cholangiocarcinoma, 27 received neoadjuvant chemoradiotherapy and 22 did not. Overall 1-, 3-, and 5-year post-transplantation survival rates were 65 per cent, 51 per cent and 41 per cent respectively in the group receiving neoadjuvant chemoradiotherapy and 91 per cent, 68 per cent and 53 per cent respectively in the group not receiving neoadjuvant chemoradiotherapy (1-year hazards ratio (HR) 4.55 (95 per cent c.i. 0.98 to 21.13), P = 0.053; 3-year HR 2.07 (95 per cent c.i. 0.78 to 5.54), P = 0.146; 5-year HR 1.71 (95 per cent c.i. 0.71 to 4.09), P = 0.229). Hepatic vascular complications were more frequent in the group receiving neoadjuvant chemoradiotherapy compared with the group not receiving neoadjuvant chemoradiotherapy (nine of 27 versus two of 22, P = 0.045). In multivariable analysis, tumour recurrence occurred less frequently in the group receiving neoadjuvant chemoradiotherapy (HR 0.30 (95 per cent c.i. 0.09 to 0.97), P = 0.044)., Conclusion: In selected patients undergoing liver transplantation for perihilar cholangiocarcinoma, neoadjuvant chemoradiotherapy resulted in a lower risk of tumour recurrence, but was associated with a higher rate of early hepatic vascular complications. Adjustments in neoadjuvant chemoradiotherapy reducing the risk of hepatic vascular complications, such as omitting radiotherapy, may further improve the outcome in patients undergoing liver transplantation for perihilar cholangiocarcinoma., (© The Author(s) 2023. Published by Oxford University Press on behalf of BJS Society Ltd.)
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- 2023
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18. Long-term follow-up of a randomized trial of biliary drainage in perihilar cholangiocarcinoma.
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Nooijen LE, Franssen S, Buis CI, Dejong CHC, den Dulk M, van Delden OM, Ijzermans JN, Groot Koerkamp B, Kazemier G, van Lienden K, Klümpen HJ, Kuipers H, Olij B, Porte RJ, Rauws EA, Voermans RP, van Gulik TM, Erdmann JI, Roos E, and Coelen RJ
- Subjects
- Humans, Follow-Up Studies, Drainage adverse effects, Bile Ducts, Intrahepatic surgery, Klatskin Tumor pathology, Bile Duct Neoplasms pathology, Cholangiocarcinoma surgery
- Abstract
Background and Aims: The DRAINAGE trial was a randomized controlled trial comparing preoperative endoscopic (EBD) and percutaneous biliary drainage (PTBD) in patients with potentially resectable, perihilar cholangiocarcinoma (pCCA). The aim of this study was to compare the long-term outcomes., Methods: Patients were randomized in four tertiary referral centers. Follow-up data were available for all included patients. Primary outcome was overall survival (OS). Secondary outcomes were readmissions, and re-interventions not including in-trial interventions., Results: A total of 54 patients were randomized; 27 in both groups. Median follow-up for both groups was 62 months (95% CI 54-70). The median OS was 13 months (95% CI 7.9-18.1) in the EBD and 7 months (95% CI 0.0-17.2) in the PTBD group (P = 0.28). Twenty (37%, n = 8 EBD vs n = 12 PTBD, P = 0.43) of 54 patients were readmitted at least once, mostly due to drainage-related complications (n = 13, 24%). Of note, 14 out of the 54 patients died within the trial. A total of 76 drainage procedures (32 EBD and 44 PTBD) were performed in 28 patients. The median number of stent or drain placements was 2 (2-4) for the EBD group and 2 (1-3) for the PTBD group (P = 0.77)., Discussion: Although this follow-up study represented a small cohort, no long-term differences in survival, readmissions, and drainage procedures for EBD and PTBD were found, even when comparing the resected and unresected group. However, this study demonstrates the complexity of biliary drainage for patients with potentially resectable pCCA, even in tertiary referral centers., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2023
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19. The Association Between Loneliness and Psychiatric Symptomatology in Older Psychiatric Outpatients.
- Author
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Schutter N, Holwerda TJ, Kuipers H, Van RHL, Stek ML, Comijs HC, Peen J, and Dekker JJM
- Subjects
- Male, Humans, Female, Aged, Cross-Sectional Studies, Social Isolation psychology, Surveys and Questionnaires, Loneliness psychology, Outpatients
- Abstract
Purpose: Loneliness in adults increases with age. Although loneliness has been found to be associated with psychiatric disorders and dementia, no information is available on prevalence of loneliness in older psychiatric patients. The aims of this study were to examine prevalence of loneliness in older psychiatric outpatients, including gender differences and associations with psychiatric disorders and social isolation., Methods: Cross-sectional study in an outpatient clinic for geriatric psychiatry between September 2013 and February 2018. Interviews were done in 181 patients., Results: 80% of participants were lonely. Loneliness was associated with having contacts in less social network domains, in women but not in men. There were no associations with DSM-IV-TR-classifications. However, loneliness was associated with higher scores on questionnaires for depression and cognitive function. Intensity of treatment did not differ significantly between lonely and non-lonely participants., Conclusion: Loneliness is highly prevalent in older psychiatric outpatients, with men and women equally affected. Loneliness should be assessed in all older psychiatric patients, especially when they show high scores on symptom checklists or have a restricted social network.
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- 2022
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20. A Multimodality Myocardial Perfusion Phantom: Initial Quantitative Imaging Results.
- Author
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Kamphuis ME, Kuipers H, Liefers HR, van Es J, Simonis FFJ, Greuter MJW, Slump CH, and Slart RHJA
- Abstract
This proof-of-concept study explores the multimodal application of a dedicated cardiac flow phantom for ground truth contrast measurements in dynamic myocardial perfusion imaging with CT, PET/CT, and MRI. A 3D-printed cardiac flow phantom and flow circuit mimics the shape of the left ventricular cavity (LVC) and three myocardial regions. The regions are filled with tissue-mimicking materials and the flow circuit regulates and measures contrast flow through LVC and myocardial regions. Normal tissue perfusion and perfusion deficits were simulated. Phantom measurements in PET/CT, CT, and MRI were evaluated with clinically used hardware and software. The reference arterial input flow was 4.0 L/min and myocardial flow 80 mL/min, corresponding to myocardial blood flow (MBF) of 1.6 mL/g/min. The phantom demonstrated successful completion of all processes involved in quantitative, multimodal myocardial perfusion imaging (MPI) applications. Contrast kinetics in time intensity curves were in line with expectations for a mimicked perfusion deficit (38 s vs. 32 s in normal tissue). Derived MBF in PET/CT and CT led to under- and overestimation of reference flow of 0.9 mL/g/min and 4.5 mL/g/min, respectively. Simulated perfusion deficit (0.8 mL/g/min) in CT resulted in MBF of 2.8 mL/g/min. We successfully performed initial, quantitative perfusion measurements with a dedicated phantom setup utilizing clinical hardware and software. These results showcase the multimodal phantom's potential.
- Published
- 2022
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21. Development of a dedicated 3D printed myocardial perfusion phantom: proof-of-concept in dynamic SPECT.
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Kamphuis ME, de Vries GJ, Kuipers H, Saaltink M, Verschoor J, Greuter MJW, Slart RHJA, and Slump CH
- Subjects
- Perfusion, Phantoms, Imaging, Printing, Three-Dimensional, Myocardial Perfusion Imaging methods, Tomography, Emission-Computed, Single-Photon methods
- Abstract
We aim to facilitate phantom-based (ground truth) evaluation of dynamic, quantitative myocardial perfusion imaging (MPI) applications. Current MPI phantoms are static representations or lack clinical hard- and software evaluation capabilities. This proof-of-concept study demonstrates the design, realisation and testing of a dedicated cardiac flow phantom. The 3D printed phantom mimics flow through a left ventricular cavity (LVC) and three myocardial segments. In the accompanying fluid circuit, tap water is pumped through the LVC and thereafter partially directed to the segments using adjustable resistances. Regulation hereof mimics perfusion deficit, whereby flow sensors serve as reference standard. Seven phantom measurements were performed while varying injected activity of
99m Tc-tetrofosmin (330-550 MBq), cardiac output (1.5-3.0 L/min) and myocardial segmental flows (50-150 mL/min). Image data from dynamic single photon emission computed tomography was analysed with clinical software. Derived time activity curves were reproducible, showing logical trends regarding selected input variables. A promising correlation was found between software computed myocardial flows and its reference ([Formula: see text]= - 0.98; p = 0.003). This proof-of-concept paper demonstrates we have successfully measured first-pass LV flow and myocardial perfusion in SPECT-MPI using a novel, dedicated, myocardial perfusion phantom. This proof-of-concept study focuses on the development of a novel, dedicated myocardial perfusion phantom, ultimately aiming to contribute to the evaluation of quantitative myocardial perfusion imaging applications., (© 2022. The Author(s).)- Published
- 2022
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22. Correction to: Development of a dedicated 3D printed myocardial perfusion phantom: proof-of-concept in dynamic SPECT.
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Kamphuis ME, de Vries GJ, Kuipers H, Saaltink M, Verschoor J, Greuter MJW, Slart RHJA, and Slump CH
- Published
- 2022
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- View/download PDF
23. Development of a dynamic myocardial perfusion phantom model for tracer kinetic measurements.
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Kamphuis ME, Kuipers H, Verschoor J, van Hespen JCG, Greuter MJW, Slart RHJA, and Slump CH
- Abstract
Background: Absolute myocardial perfusion imaging (MPI) is beneficial in the diagnosis and prognosis of patients with suspected or known coronary artery disease. However, validation and standardization of perfusion estimates across centers is needed to ensure safe and adequate integration into the clinical workflow. Physical myocardial perfusion models can contribute to this clinical need as these can provide ground-truth validation of perfusion estimates in a simplified, though controlled setup. This work presents the design and realization of such a myocardial perfusion phantom and highlights initial performance testing of the overall phantom setup using dynamic single photon emission computed tomography., Results: Due to anatomical and (patho-)physiological representation in the 3D printed myocardial perfusion phantom, we were able to acquire 22 dynamic MPI datasets in which
99m Tc-labelled tracer kinetics was measured and analyzed using clinical MPI software. After phantom setup optimization, time activity curve analysis was executed for measurements with normal myocardial perfusion settings (1.5 mL/g/min) and with settings containing a regional or global perfusion deficit (0.8 mL/g/min). In these measurements, a specific amount of activated carbon was used to adsorb radiotracer in the simulated myocardial tissue. Such mimicking of myocardial tracer uptake and retention over time satisfactorily matched patient tracer kinetics. For normal perfusion levels, the absolute mean error between computed myocardial blood flow and ground-truth flow settings ranged between 0.1 and 0.4 mL/g/min., Conclusion: The presented myocardial perfusion phantom is a first step toward ground-truth validation of multimodal, absolute MPI applications in the clinical setting. Its dedicated and 3D printed design enables tracer kinetic measurement, including time activity curve and potentially compartmental myocardial blood flow analysis., (© 2022. The Author(s).)- Published
- 2022
- Full Text
- View/download PDF
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