Publications by authors named "Hans van den Berg"
Article Synopsis
- Trace metal contamination, especially from mercury (Hg) and lead (Pb), can harm wildlife health, particularly affecting young birds' immune systems.
- This study focused on how these metals influence immune responses in Pekin ducklings following a viral challenge, revealing that Hg (II) increased pro-inflammatory gene expression while Pb (II) resulted in lower natural antibodies and reduced white blood cells.
- Overall, both metals negatively impacted immune competence in ducklings, leading to inflammation and impaired immune function.
Historical mining activities in Svalbard (79°N/12°E) have caused local mercury (Hg) contamination. To address the potential immunomodulatory effects of environmental Hg on Arctic organisms, we collected newborn barnacle goslings () and herded them in either a control or mining site, differing in Hg levels. An additional group at the mining site was exposed to extra inorganic Hg(II) via supplementary feed.
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- The study evaluates the effectiveness of computed tomography-derived fractional flow reserve (CT-FFR) in diagnosing coronary artery disease (CAD) in patients preparing for transcatheter aortic valve replacement (TAVR).
- It compares CT-FFR with traditional coronary computed tomography angiography (CCTA) and invasive coronary angiography (ICA) to determine which method is more accurate for diagnosing significant coronary stenosis.
- The results show that CT-FFR has higher sensitivity and diagnostic accuracy than CCTA and could potentially reduce the need for invasive procedures in a significant number of patients.
Article Synopsis
- Controlling magnon densities in magnetic materials can improve spin transport in devices, and this study shows how large out-of-equilibrium magnon densities are created in a thin-film magnetic insulator using microwave excitation.
- Researchers utilize scanning-probe magnetometry with diamond electron spins to image both coherent spin waves and the resulting incoherent magnon gas, which extends hundreds of micrometers from the excitation area.
- The findings reveal that the gas density surpasses expectations for a boson system, highlighting new avenues for manipulating spin transport and magnetic dynamics in specific directions.
Article Synopsis
- The Wood mouse (Apodemus sylvaticus) serves as a reservoir for zoonotic infections and may have reduced ability to fight diseases due to exposure to immunotoxins like cadmium.
- This study focuses on how cadmium exposure affects the antibody responses of wood mice in polluted versus non-polluted areas in the Netherlands, measuring the primary antibody response after immunization.
- Findings indicate that higher cadmium levels, particularly in mice from polluted sites, correlate with decreased antibody-producing cells, suggesting that cadmium weakens immune responses and could enhance disease susceptibility.
Article Synopsis
- Mercury (Hg) is a toxic metal found everywhere and can harm the immune system of birds, particularly in response to viral infections.
- In a study, chicken immune cell lines were exposed to Hg to assess its effects, showing that Hg is toxic in a dose-dependent way and depletes protective glutathione (GSH).
- The exposure to Hg disrupted normal immune functions, such as reducing cell proliferation and cytokine production, suggesting that Hg could lead to serious immune disorders in birds.
Elevated levels of lead have been found in waterfowl, due to human activities. Lead may cause immunomodulatory effects, but the mechanisms are largely unknown, especially after viral challenges. To characterize avian immunomodulatory hazards of lead (Pb) , we used chicken macrophage (HD-11) and B-lymphocyte (DT40) cell lines, as in vitro models for the innate and adaptive immune systems, respectively.
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- * This study investigated how AgS-NPs affect earthworm bioturbation and how this bioturbation influences the movement of AgS-NPs in soil using sandy loamy soil columns with and without earthworms.
- * Results indicated that earthworm activity enhances the vertical displacement of Ag, but AgS-NPs did not significantly alter earthworm behavior or soil porosity, suggesting that earthworm burrowing is important in studying nanoparticle dynamics in soils.
Diamond membrane devices containing optically coherent nitrogen-vacancy (NV) centers are key to enable novel cryogenic experiments such as optical ground-state cooling of hybrid spin-mechanical systems and efficient entanglement distribution in quantum networks. Here, we report on the fabrication of a (3.4 ± 0.
View Article and Find Full Text PDFToxic trace metals are widespread contaminants that are potentially immunotoxic even at environmentally low exposure levels. They can modulate the immunity to infections, e.g.
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- The study investigates how the properties of silver nanoparticles (AgNPs), specifically size and surface charge, affect their uptake and toxic effects on macrophage cells.
- Two sizes of AgNPs (20 nm and 50 nm) with different surface coatings were synthesized and tested for their impact on cell viability, TNF-α induction, ATP production, and reactive oxygen species (ROS) generation.
- Results showed that smaller (20 nm) and negatively charged (BSA-coated) AgNPs were more toxic, leading to significantly higher TNF-α levels, while ROS generation was notably observed only with the positively charged 20 nm AgNPs.
Article Synopsis
- Some patients with chronic abdominal pain may have anterior cutaneous nerve entrapment syndrome (ACNES), which can be treated through local anesthetic injections or surgery like neurectomy.
- *The study compares the effectiveness of pulsed radiofrequency (PRF) treatment with neurectomy in ACNES patients who have not found lasting relief from injections, tracking pain relief and patient satisfaction over an 8-week period.
- *This trial aims to provide evidence for minimally invasive options like PRF, potentially reducing the need for surgical interventions in managing ACNES.*
Article Synopsis
- The study investigated how different charged polystyrene nanoparticles (PS-NPs) cross the placental barrier using an in vitro model with BeWo b30 cells.
- Characterization of the PS-NPs included size, charge, and their protein coating, finding that translocation was not linked to the charge of the nanoparticles.
- The findings demonstrated that while some PS-NPs translocated less than the known drug amoxicillin, their movement across the barrier was mainly due to passive diffusion rather than specific transport mechanisms, indicating the model's potential for further research on nanoparticle effects on fetal exposure.
Article Synopsis
- Oral exposure to nanoparticles (NPs) is becoming more common, making it essential to evaluate how effectively these particles are absorbed in the body.
- An in vitro model using Caco-2/HT29-MTX cells previously showed that NPs' translocation depends on their surface charge, particularly focusing on 50 nm polystyrene NPs.
- The in vivo study with rats confirmed that negatively charged NPs are absorbed more than others, but the measured bioavailability was significantly lower than predicted by the in vitro model, indicating that the latter can help prioritize which NPs to test further but shouldn’t directly predict bioavailability.
Objective: To determine women's satisfaction with pain relief using patient controlled analgesia with remifentanil compared with epidural analgesia during labour.
Design: Multicentre randomised controlled equivalence trial.
Setting: 15 hospitals in the Netherlands.
Article Synopsis
- Researchers isolated a 1,728 bp sequence of the cassava granule-bound starch synthase (GBSSI) promoter, which has light- and sugar-responsive elements.
- The isolated GBSSI sequence (1,167 bp) was cloned into vectors to test its ability to drive expression of the luciferase gene in cassava plants.
- Results showed while the 35S promoter activated luciferase in all plant parts, the GBSSI promoter specifically enhanced expression in tuberous roots, making it a strong candidate for targeted gene expression in cassava.
Article Synopsis
- - Current assessments of petroleum risks focus mainly on narcosis, but research has shown that oil contains chemicals that can disrupt endocrine functions, including estrogenic and antiestrogenic activities.
- - This study, part of a series, tested 11 different crude oils and refined products using modified mammalian cells to evaluate their estrogenic effects; most oils exhibited significant estrogenic responses, though much weaker than the hormone 17β-estradiol (E2).
- - Notably, one type of nautical fuel oil was found to significantly promote cell growth in cancer cells and trigger the expression of estrogen-sensitive genes, suggesting that oils could have broader biological effects beyond just receptor interactions.
Article Synopsis
- The DR-H4IIE.Luc bioassay measures how dioxin and similar toxins activate the AhR pathway, indicating their toxic effects.
- It was used to assess the total dioxin-equivalent toxicity in the gonads and livers of cod females from the southern Baltic Sea, with results showing varying toxicity levels based on exposure time.
- While the 48-hour bioassay indicated certain correlations with PCBs, the potential impact on cod larvae survival is still under investigation.
Article Synopsis
- * The study created QSAR models using both existing literature and new experimental data, focusing on chemical properties such as the octanol/water partition coefficient and molecular orbital energies.
- * Results suggest that toxicity data from Daphnia magna can successfully predict toxicity in fish, allowing researchers to estimate the toxicity of various compounds without extensive animal testing—83 candidate chemicals were identified from a larger database for further evaluation using these QSAR models.
Article Synopsis
- The study examines how polychlorinated biphenyls (PCBs) affect energy use in fasting silver European eels over a 27-day period while they are either resting or swimming long distances.
- PCB-exposed eels showed less weight loss and lower metabolic rates compared to controls, especially those swimming, which demonstrated a significant reduction in oxygen consumption over time.
- Notably, the weights of the spleen and liver increased in swimming PCB-exposed eels, indicating potential health impacts that could hinder the European eel's reproduction.
Breast cancer cells show overexpression of estrogen receptor (ER) alpha relative to ERbeta compared to normal breast tissues. This observation has lead to the hypothesis that ERbeta may modulate the proliferative effect of ERalpha. This study investigated how variable cellular expression ratios of the ERalpha and ERbeta modulate the effects on cell proliferation induced by ERalpha or ERbeta agonists, respectively.
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- - Nonylphenol (NP) is an environmental endocrine disruptor, with its bioavailability and biodegradability studied in the contaminated sediment of a tributary of the Ebro River, Spain.
- - The study showed that over 95% of NP quickly desorbed into the water and that aerobic biodegradation effectively reduced both NP concentration and its estrogenic activity by 97% and 94%, respectively.
- - The findings suggest that NP can serve as an indicator for monitoring estrogenic activity in sediment, while also indicating that other estrogenic compounds may be present, warranting further examination in different river sediments.
Quantitative structure-activity relationship (QSAR) models are expected to play a crucial role in reducing the number of animals to be used for toxicity testing resulting from the adoption of the new European Union chemical control system called Registration, Evaluation, and Authorization of Chemicals (REACH). The objective of the present study was to generate in vitro acute toxicity data that could be used to develop a QSAR model to describe acute in vivo toxicity of chlorinated alkanes. Cytotoxicity of a series of chlorinated alkanes to Chinese hamster ovary (CHO) cells was observed at concentrations similar to those that have been shown previously to be toxic to fish.
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