Publications by authors named "Jan W Hesselink"

Background: Microbrachytherapy enables high local tumor doses sparing surrounding tissues by intratumoral injection of radioactive holmium-166 microspheres (Ho-MS). Magnetic resonance imaging (MRI) cannot properly detect high local Ho-MS concentrations and single-photon emission computed tomography has insufficient resolution. Computed tomography (CT) is quicker and cheaper with high resolution and previously enabled Ho quantification.

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Introduction: In the Netherlands, the veterinary disciplinary system is governmentally executed and was originally designed to provide an educational effect on veterinarians as part of maintaining quality standards.

Methods: Over 900 veterinarians were questioned (20% of the total number of veterinarians working in veterinary medicine in the Netherlands). It was ascertained whether or not they were aware of the disciplinary system, if it affected their way of working and what impact it had on their way of working after having faced a disciplinary case.

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In most countries, a veterinary disciplinary system is in force to ensure the quality of the veterinary profession and to offer an objective platform for complaints. We present an analysis of 15 years of veterinary disciplinary verdicts (2001-2016) to compare facts and figures and identify which factors are of major influence on the outcome of the verdicts. Rulings were collected from both paper files and the digital database of the veterinary disciplinary council (VDC), categorized, and used to create a database that enabled a statistical analysis.

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Introduction: Minimally invasive microbrachytherapy is in development to treat solid tumors by intratumoral injection of (radioactive) holmium-166 (Ho) microspheres (MS). A high local dose can be administered with minimal damage to surrounding tissue because of the short soft tissue penetration depth of Ho beta radiation. We aimed to prospectively evaluate the safety and efficacy of Ho microbrachytherapy in client-owned canine patients with soft tissue sarcomas (STS).

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In this case study, a client-owned dog with a large pituitary tumor was experimentally treated by intratumoral injection of radioactive holmium-166 microspheres (HoMS), named Ho microbrachytherapy. To our knowledge, this is the first intracranial intratumoral treatment through needle injection of radioactive microspheres. A 10-year-old Jack Russell Terrier was referred to the Clinic for Companion Animal Health (Faculty of Veterinary Medicine, Utrecht University, The Netherlands) with behavioral changes, restlessness, stiff gait, and compulsive circling.

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The COVID-19 pandemic raised concerns that companion animals might be infected with, and could become a reservoir of, SARS-CoV-2. As cats are popular pets and susceptible to Coronavirus, we investigated the seroprevalence of SARS-CoV-2 antibodies in shelter cats housed in Dutch animal shelters during the COVID-19 pandemic. In this large-scale cross-sectional study, serum samples of shelter cats were collected during the second wave of human COVID-19 infections in The Netherlands.

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Nanobody-targeted photodynamic therapy (NB-PDT) has been developed as a potent and tumor-selective treatment, using nanobodies (NBs) to deliver a photosensitizer (PS) specifically to cancer cells. Upon local light application, reactive oxygen species are formed and consequent cell death occurs. NB-PDT has preclinically shown evident success and we next aim to treat cats with oral squamous cell carcinoma (OSCC), which has very limited therapeutic options and is regarded as a natural model of human head and neck SCC.

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Hypercortisolism is caused by a cortisol-secreting adrenocortical tumour (ACT) in approximately 15%-20% of cases in dogs. Little is known about which molecular markers are associated with malignant behaviour of canine ACTs. The objective of this study was to identify molecular markers of prognosis, which could be useful to refine prognostic prediction and to identify potential treatment targets.

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Article Synopsis
  • Pseudopregnancy is a common reproductive issue in dairy goats, with a study evaluating its incidence and risk factors on Dutch farms.
  • The study found that the annual rate of pseudopregnancy ranged from 1% to 54%, averaging 17%, and had significant links to extended lactation and ultrasound use.
  • While the recommended treatment is two doses of prostaglandins, only 10% of farms followed this correctly, with many using higher doses than advised.
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A cortisol-secreting adrenocortical tumour (ACT) is the cause of naturally occurring canine hypercortisolism in approximately 15% to 20% of cases. The differentiation between an adrenocortical adenoma and carcinoma is usually based on histopathology. However, histopathological parameters have never been linked to the dogs' survival.

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Anastomotic leakage is a disastrous complication after colorectal surgery. Although current methods for leakage prevention have different levels of clinical efficacy, they are until now imperfect solutions. Stem cell therapy using ASC sheets could provide a solution to this problem.

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Tissue healing is a highly complex process involving a cascade of biochemical and cellular events. Excessive inflammation can impair the healing response. Previous in vitro studies have shown that mesenchymal stromal cells can modulate macrophage-induced inflammation and, therefore, are promising candidates for cell-based therapies aimed at promoting tissue repair.

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Adipose tissue-derived stem cells (ASCs) are known to be tissue-healing promoters due to their cellular plasticity and secretion of paracrine factors. Cultured ASC sheets provide a novel method of ASC application and can retain ASCs at the targeted tissue. The purpose of this systematic review is to evaluate preclinical studies using ASC sheet transplantation therapy for promoting tissue healing.

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The most dreaded complication of colorectal surgery is anastomotic leakage. Adipose tissue-derived stem cell sheets (ASC sheets) prepared from temperature-responsive culture surfaces can be easily transplanted onto tissues. These sheets are proposed to improve cell transplant efficiency and enhance wound healing.

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Adipose tissue-derived stem cells (ASCs) are known to be able to promote repair of injured tissue via paracrine factors. However, the effect of cell density and inflammatory cytokines on the paracrine ability of ASCs remains largely unknown. To investigate these effects, ASCs were cultured in 8000 cells/cm, 20,000 cells/cm, 50,000 cells/cm, and 400,000 cells/cm with and without 10 or 20 ng/ml tumor necrosis factor alpha (TNFα) and 25 or 50 ng/ml interferon gamma (IFNγ).

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Unlabelled: Transforming growth factor-β (TGF-β) promotes cancer invasion and metastasis and is therefore a potential drug target for cancer treatment. Fresolimumab, which neutralizes all mammalian active isoforms of TGF-β, was radiolabeled with (89)Zr for PET to analyze TGF-β expression, antibody tumor uptake, and organ distribution.

Methods: (89)Zr was conjugated to fresolimumab using the chelator N-succinyldesferrioxamine-B-tetrafluorphenol.

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Non-invasive imaging of angiogenesis could ease the optimization of antiangiogenesis treatments for cancer. In this study, we evaluated the role of VEGF-PET as a biomarker of dynamic angiogenic changes in tumors following treatment with the kinase inhibitor sunitinib. The effects of sunitinib treatment and withdrawal on the tumor was investigated using the new VEGF-PET tracer (89)Zr-ranibizumab as well as (18)F-FDG PET, and (15)O-water PET in mouse xenograft models of human cancer.

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Upregulation of heme oxygenase-1 (HO-1) has been proposed as a critical mechanism protecting against cellular stress during liver transplantation, providing a potential target for new therapeutic interventions. We investigated the feasibility of in vivo bioluminescence imaging (BLI) to noninvasively quantify the spatiotemporal expression of HO-1 after warm hepatic ischemia in living animals. Luciferase activity was measured by BLI as an index of HO-1 transcription in transgenic reporter mice (Ho1-luc) at standardized time points after 60 minutes of warm hepatic ischemia.

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The development of a simulation model, "JohneSSim", was part of a research program aimed at designing a national Johne's disease control program for The Netherlands. Initially, the focus was mainly directed towards different compulsory "test-and-cull" strategies. However, the results from the JohneSSim model showed that eradication of Johne's disease based on such strategies would not be possible within 20 years and that it was also economically unattractive.

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A dynamic and stochastic simulation model (the "JohneSSim model") was developed to evaluate the economic and epidemiological effects of different strategies for control of paratuberculosis in dairy herds. Animals occupy one of the six defined infection states; the spread of Johne's disease is modeled with five infection routes. Many different dairy farm situations can be simulated.

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