• Multiple cases of familial transmission of community-acquired methicillin-resistant Staphylococcus aureus.

      Huijsdens, Xander W; Santen-Verheuvel, Marga G van; Spalburg, Emile; Heck, Max E O C; Pluister, Gerlinde N; Eijkelkamp, B A; Neeling, Albert J de; Wannet, Wim J B (2006-08-01)
      The worldwide emergence of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) can have severe public health implications. Familial transmissions of CA-MRSA in The Netherlands were investigated. Among the families studied, two clusters of CA-MRSA could be identified. This report demonstrates that family members can serve as reservoirs of CA-MRSA which may become a serious problem in containing the spread of MRSA.
    • Multiple-locus variable-number tandem repeat analysis of Neisseria meningitidis yields groupings similar to those obtained by multilocus sequence typing.

      Schouls, Leo M; Ende, Arie van der; Damen, Marjolein; Pol, Ingrid van de (2006-04-01)
      We identified many variable-number tandem repeat (VNTR) loci in the genomes of Neisseria meningitidis serogroups A, B, and C and utilized a number of these loci to develop a multiple-locus variable-number tandem repeat analysis (MLVA). Eighty-five N. meningitidis serogroup B and C isolates obtained from Dutch patients with invasive meningococcal disease and seven reference strains were analyzed using MLVA and multilocus sequence typing (MLST). MLVA, based on eight VNTR loci with limited variability in the number of repeats, yielded clustering of the strains similar to that obtained by MLST, with congruence between both methods amounting to 69%. The ability to recognize clonal complexes makes MLVA a valuable high-throughput method to serve as a tool complementary to MLST. Four highly variable VNTR loci were used in a second assay to analyze N. meningitidis serogroup C strains collected during an outbreak of meningococcal disease in The Netherlands. Typing based on the latter VNTR loci enabled differentiation of isolates with identical MLST sequence types and grouped epidemiologically related strains.
    • Multiscale Coupling Strategy for Nano Ecotoxicology Prediction.

      Wang, Zhuang; Vijver, Martina G; Peijnenburg, Willie J G M (2018-06-27)
    • Multiwall carbon nanotubes modulate paraquat toxicity in Arabidopsis thaliana.

      Fan, Xiaoji; Xu, Jiahui; Lavoie, Michel; Peijnenburg, W J G M; Zhu, Youchao; Lu, Tao; Fu, Zhengwei; Zhu, Tingheng; Qian, Haifeng (2018-02)
      Carbon nanotubes can be either toxic or beneficial to plant growth and can also modulate toxicity of organic contaminants through surface sorption. The complex interacting toxic effects of carbon nanotubes and organic contaminants in plants have received little attention in the literature to date. In this study, the toxicity of multiwall carbon nanotubes (MWCNT, 50 mg/L) and paraquat (MV, 0.82 mg/L), separately or in combination, were evaluated at the physiological and the proteomic level in Arabidopsis thaliana for 7-14 days. The results revealed that the exposure to MWCNT had no inhibitory effect on the growth of shoots and leaves. Rather, MWCNT stimulated the relative electron transport rate and the effective photochemical quantum yield of PSII value as compared to the control by around 12% and lateral root production up to nearly 4-fold as compared to the control. The protective effect of MWCNT on MV toxicity on the root surface area could be quantitatively explained by the extent of MV adsorption on MWCNT and was related to stimulation of photosynthesis, antioxidant protection and number and area of lateral roots which in turn helped nutrient assimilation. The influence of MWCNT and MV on photosynthesis and oxidative stress at the physiological level was consistent with the proteomics analysis, with various over-expressed photosynthesis-related proteins (by more than 2 folds) and various under-expressed oxidative stress related proteins (by about 2-3 folds). This study brings new insights into the interactive effects of two xenobiotics (MWCNT and MV) on the physiology of a model plant.
    • Mumps infection but not childhood vaccination induces persistent polyfunctional CD8+ T-cell memory.

      de Wit, Jelle; Emmelot, Maarten E; Poelen, Martien C M; van Binnendijk, Rob S; van der Lee, Saskia; van Baarle, Debbie; Han, Wanda G H; van Els, Cécile A C M; Kaaijk, Patricia (2018-01-12)
    • Mutant frequencies and spectra depend on growth state and passage number in cells cultured from transgenic lacZ-plasmid reporter mice.

      Busuttil, Rita A; Rubio, Miguel; Dollé, Martijn E T; Campisi, Judith; Vijg, Jan (2006-01-05)
      Transgenic mice harboring the lacZ gene within a plasmid that can be recovered and amplified in Escherichia coli, to establish mutant frequencies and spectra, have provided crucial insights into the relationships between mutations, cancer and aging in vivo. Here, we use embryonic fibroblasts from transgenic lacZ-plasmid reporter mice to determine the relationship between cell proliferation in culture and mutations induced by ultraviolet (UV) light. A single dose of 2.5J/m2 of UVC to actively proliferating cells caused an approximately eight-fold increase in mutant frequency 24 h after irradiation. Identically treated quiescent cells showed a two-fold increase in mutant frequency. Thus, whereas proliferation facilitated the acquisition of mutations, it was not an absolute requirement. Characterization of the UV-induced mutations indicated that the lower mutant frequency in quiescent cells was due mainly to a reduction in point mutations; size-change mutations, indicative of translocations or deletions, were relatively unaffected by the growth state of the cells. To investigate long-term genomic stability after UVC-induced damage, we monitored the lacZ locus in irradiated cells passaged for many generations in culture. The results indicated the emergence of jackpot mutations of rapidly changing frequency, most likely reflecting the successive emergence and decline of dominant cell clones during long-term culture. These findings show that the lacZ-plasmid locus is a valid reporter for studying induced mutations in short-term cultures of both quiescent and proliferating fibroblasts. In long-term cultures, the locus is less suitable for studying induced mutations owing to the instability of the cell population.
    • Mycobacterium tuberculosis lineage 1 genetic diversity in Pará, Brazil, suggests common ancestry with east-African isolates potentially linked to historical slave trade.

      Conceição, Emilyn Costa; Refregier, Guislaine; Gomes, Harrison Magdinier; Olessa-Daragon, Xavier; Coll, Francesc; Ratovonirina, Noël Harijaona; Rasolofo-Razanamparany, Voahangy; Lopes, Maria Luiza; Van Soolingen, Dick; Rutaihwa, Liliana; et al. (2019-06-03)
    • Mycotoxin Biomarkers of Exposure: A Comprehensive Review

      Vidal, Arnau; Mengelers, Marcel; Yang, Shupeng; De Saeger, Sarah; De Boevre, Marthe; Laboratory of Food Analysis, Dept. of Bioanalysis, Faculty of Pharmaceutical Sciences; Ghent Univ.; Ghent Belgium; Dept. of Food Safety; National Inst. of Public Health and the Environment; Bilthoven The Netherlands; Inst. of Apicultural Research, Chinese Acad. of Agricultural Sciences, Key Laboratory of Bee Products for Quality and Safety Control, Laboratory of Risk Assessment for Quality and Safety of Bee Products; Bee Product Quality Supervision and Testing Center; Ministry of Agriculture Beijing 100093 People's Republic of China; Laboratory of Food Analysis, Dept. of Bioanalysis, Faculty of Pharmaceutical Sciences; Ghent Univ.; Ghent Belgium; Laboratory of Food Analysis, Dept. of Bioanalysis, Faculty of Pharmaceutical Sciences; Ghent Univ.; Ghent Belgium (2018-07-06)
    • The Nagoya protocol on access to genetic resources and benefit sharing: best practices for users of lactic acid bacteria

      Flach, J; dos Santos Ribeiro, C; van der Waal, MB; van der Waal, RX; Claassen, E; van de Burgwal, LHM (2019-07-15)
    • Nanomaterial exposures for worker, consumer and the general public

      Kuhlbusch, Thomas A.J.; Wijnhoven, Susan W.P.; Haase, Andrea (2018-04)
    • Nanomaterials Versus Ambient Ultrafine Particles: An Opportunity to Exchange Toxicology Knowledge.

      Stone, Vicki; Miller, Mark R; Clift, Martin J D; Elder, Alison; Mills, Nicholas L; Møller, Peter; Schins, Roel P F; Vogel, Ulla; Kreyling, Wolfgang G; Alstrup Jensen, Keld; et al. (2017)
      A rich body of literature exists that has demonstrated adverse human health effects following exposure to ambient air particulate matter (PM), and there is strong support for an important role of ultrafine (nanosized) particles. At present, relatively few human health or epidemiology data exist for engineered nanomaterials (NMs) despite clear parallels in their physicochemical properties and biological actions inin vitromodels.
    • Nanomedicinal products: a survey on specific toxicity and side effects.

      Brand, Walter; Noorlander, Cornelle W; Giannakou, Christina; De Jong, Wim H; Kooi, Myrna W; Park, Margriet Vdz; Vandebriel, Rob J; Bosselaers, Irene Em; Scholl, Joep Hg; Geertsma, Robert E (2017)
      Due to their specific properties and pharmacokinetics, nanomedicinal products (NMPs) may present different toxicity and side effects compared to non-nanoformulated, conventional medicines. To facilitate the safety assessment of NMPs, we aimed to gain insight into toxic effects specific for NMPs by systematically analyzing the available toxicity data on approved NMPs in the European Union. In addition, by comparing five sets of products with the same active pharmaceutical ingredient (API) in a conventional formulation versus a nanoformulation, we aimed to identify any side effects specific for the nano aspect of NMPs. The objective was to investigate whether specific toxicity could be related to certain structural types of NMPs and whether a nanoformulation of an API altered the nature of side effects of the product in humans compared to a conventional formulation. The survey of toxicity data did not reveal nanospecific toxicity that could be related to certain types of structures of NMPs, other than those reported previously in relation to accumulation of iron nanoparticles (NPs). However, given the limited data for some of the product groups or toxicological end points in the analysis, conclusions with regard to (a lack of) potential nanomedicine-specific effects need to be considered carefully. Results from the comparison of side effects of five sets of drugs (mainly liposomes and/or cytostatics) confirmed the induction of pseudo-allergic responses associated with specific NMPs in the literature, in addition to the side effects common to both nanoformulations and regular formulations, eg, with liposomal doxorubicin, and possibly liposomal daunorubicin. Based on the available data, immunotoxicological effects of certain NMPs cannot be excluded, and we conclude that this end point requires further attention.
    • Nanoparticles induce dermal and intestinal innate immune system responses in zebrafish embryos

      Brun, Nadja R.; Koch, Bjørn E. V.; Varela, Mónica; Peijnenburg, Willie J. G. M.; Spaink, Herman P.; Vijver, Martina G.; Institute of Environmental Sciences (CML); Institute of Biology; Institute of Biology; Institute of Environmental Sciences (CML); et al. (2018)
      Metal and plastic nanoparticles elicit innate immune responses in the skin and intestine of zebrafish embryos potentially serving as key event for AOPs.
    • Narcolepsy and adjuvanted pandemic influenza A (H1N1) 2009 vaccines - Multi-country assessment.

      Weibel, Daniel; Sturkenboom, Miriam; Black, Steven; de Ridder, Maria; Dodd, Caitlin; Bonhoeffer, Jan; Vanrolleghem, Ann; van der Maas, Nicoline; Lammers, Gert Jan; Overeem, Sebastiaan; et al. (2018)
      In 2010, a safety signal was detected for narcolepsy following vaccination with Pandemrix, an AS03-adjuvanted monovalent pandemic H1N1 influenza (pH1N1) vaccine. To further assess a possible association and inform policy on future use of adjuvants, we conducted a multi-country study of narcolepsy and adjuvanted pH1N1 vaccines.
    • A national FFQ for the Netherlands (the FFQ-NL1.0): development and compatibility with existing Dutch FFQs.

      Eussen, Simone Jpm; van Dongen, Martien Cjm; Wijckmans, Nicole Eg; Meijboom, Saskia; Brants, Henny Am; de Vries, Jeanne Hm; Bueno-de-Mesquita, H Bas; Geelen, Anouk; Sluik, Diewertje; Feskens, Edith Jm; et al. (2018-04-22)
      In the Netherlands, various FFQs have been administered in large cohort studies, which hampers comparison and pooling of dietary data. The present study aimed to describe the development of a standardized Dutch FFQ, FFQ-NL1.0, and assess its compatibility with existing Dutch FFQs.
    • National laboratory-based surveillance system for antimicrobial resistance: a successful tool to support the control of antimicrobial resistance in the Netherlands.

      Altorf-van der Kuil, Wieke; Schoffelen, Annelot F; de Greeff, Sabine C; Thijsen, Steven Ft; Alblas, H Jeroen; Notermans, Daan W; Vlek, Anne Lm; van der Sande, Marianne Ab; Leenstra, Tjalling (2017)
      An important cornerstone in the control of antimicrobial resistance (AMR) is a well-designed quantitative system for the surveillance of spread and temporal trends in AMR. Since 2008, the Dutch national AMR surveillance system, based on routine data from medical microbiological laboratories (MMLs), has developed into a successful tool to support the control of AMR in the Netherlands. It provides background information for policy making in public health and healthcare services, supports development of empirical antibiotic therapy guidelines and facilitates in-depth research. In addition, participation of the MMLs in the national AMR surveillance network has contributed to sharing of knowledge and quality improvement. A future improvement will be the implementation of a new semantic standard together with standardised data transfer, which will reduce errors in data handling and enable a more real-time surveillance. Furthermore, the scientific impact and the possibility of detecting outbreaks may be amplified by merging the AMR surveillance database with databases from selected pathogen-based surveillance programmes containing patient data and genotypic typing data.
    • National prevalence estimates of chlamydia and gonorrhoea in the Netherlands.

      Heijne, Janneke C M; van den Broek, Ingrid V F; Bruisten, Sylvia M; van Bergen, Jan E A; de Graaf, Hanneke; van Benthem, Birgit H B (2018-06-20)
      National prevalence estimates of Chlamydia trachomatis (chlamydia) and Neisseria gonorrhoeae (gonorrhoea) are important for providing insights in the occurrence and control of these STIs. The aim was to obtain national prevalence estimates for chlamydia and gonorrhoea and to investigate risk factors associated with infection.
    • A nationwide retrospective observational study of population newborn screening for medium-chain acyl-CoA dehydrogenase (MCAD) deficiency in the Netherlands.

      Jager, Emmalie A; Kuijpers, Myrthe M; Bosch, Annet M; Mulder, Margot F; Gozalbo, Estela R; Visser, Gepke; de Vries, Maaike; Williams, Monique; Waterham, Hans R; van Spronsen, Francjan J; et al. (2019-09-01)
    • Natural outdoor environments and mental health: Stress as a possible mechanism.

      Triguero-Mas, Margarita; Donaire-Gonzalez, David; Seto, Edmund; Valentín, Antònia; Martínez, David; Smith, Graham; Hurst, Gemma; Carrasco-Turigas, Glòria; Masterson, Daniel; van den Berg, Magdalena; et al. (2017-10)
      Better mental health has been associated with exposure to natural outdoor environments (NOE). However, comprehensive studies including several indicators of exposure and outcomes, potential effect modifiers and mediators are scarce.