Dynamics of Aspergillus fumigatus in Azole Fungicide-Containing Plant Waste in the Netherlands (2016-2017).

The treatment of patients suffering from Aspergillus diseases is hampered due to infections with Aspergillus fumigatus that are already resistant to medical azoles. Previous work has suggested that A. fumigatus likely gains resistance through environmental azole exposure in so-called hot spots. Here, we investigated A. fumigatus resistance dynamics over time at three sites at which farmers used azole fungicides for crop protection. Over 16 months, 114 samples were taken from stockpiles of decaying plant waste. A. fumigatus and azole fungicide residues were ubiquitously present in the plant waste. On average, 105A. fumigatus CFU/g was recovered, of which roughly half were itraconazole and tebuconazole resistant. Similar tandem repeat-mediated resistance mechanisms were found in colonies cultured from plant waste as reported in clinical azole-resistant isolates. Our results show a consistent high burden of azole-resistant A. fumigatus in azole-containing plant waste and underscores the need to further investigate resistance-reducing interventions and transmission routes.IMPORTANCEAspergillus fumigatus is consistently present independently on season at a high abundance in plant waste material throughout the sampling period. Our study confirmed that long-term storage sites of azole-containing decaying plant material can indeed be considered hot spots, which can sustain resistance development and maintenance in A. fumigatus Roughly half of individual isolates were azole resistant and carried genetic mutations that are highly similar to those found in patients with azole-resistant invasive aspergillosis. Our work suggests that environmental sources of azole resistance in A. fumigatus may be important, underscoring the need for further studies on environment-to-patient transmission routes.

Environmental Hotspots for Azole Resistance Selection of Aspergillus fumigatus, the Netherlands.

Azole resistance is a major concern for treatment of infections with Aspergillus fumigatus. Environmental resistance selection is a main route for Aspergillus spp. to acquire azole resistance. We investigated the presence of environmental hotspots for resistance selection in the Netherlands on the basis of the ability of A. fumigatus to grow and reproduce in the presence of azole fungicide residues. We identified 3 hotspots: flower bulb waste, green waste material, and wood chippings. We recovered azole-resistant A. fumigatus from these sites; all fungi contained cyp51A tandem repeat-mediated resistance mechanisms identical to those found in clinical isolates. Tebuconazole, epoxiconazole, and prothioconazole were the most frequently found fungicide residues. Stockpiles of plant waste contained the highest levels of azole-resistant A. fumigatus, and active aerobic composting reduced Aspergillus colony counts. Preventing plant waste stockpiling or creating unfavorable conditions for A. fumigatus to grow in stockpiles might reduce environmental resistance burden.

Characterization of titanium dioxide nanoparticles in food products: analytical methods to define nanoparticles.

Titanium dioxide (TiO2) is a common food additive used to enhance the white color, brightness, and sometimes flavor of a variety of food products. In this study 7 food grade TiO2 materials (E171), 24 food products, and 3 personal care products were investigated for their TiO2 content and the number-based size distribution of TiO2 particles present in these products. Three principally different methods have been used to determine the number-based size distribution of TiO2 particles: electron microscopy, asymmetric flow field-flow fractionation combined with inductively coupled mass spectrometry, and single-particle inductively coupled mass spectrometry. The results show that all E171 materials have similar size distributions with primary particle sizes in the range of 60-300 nm. Depending on the analytical method used, 10-15% of the particles in these materials had sizes below 100 nm. In 24 of the 27 foods and personal care products detectable amounts of titanium were found ranging from 0.02 to 9.0 mg TiO2/g product. The number-based size distributions for TiO2 particles in the food and personal care products showed that 5-10% of the particles in these products had sizes below 100 nm, comparable to that found in the E171 materials. Comparable size distributions were found using the three principally different analytical methods. Although the applied methods are considered state of the art, they showed practical size limits for TiO2 particles in the range of 20-50 nm, which may introduce a significant bias in the size distribution because particles <20 nm are excluded. This shows the inability of current state of the art methods to support the European Union recommendation for the definition of nanomaterials.

Considerations on the EU definition of a nanomaterial: science to support policy making.

In recent years, an increasing number of applications and products containing or using nanomaterials have become available. This has raised concerns that some of these materials may introduce new risks for humans or the environment. A clear definition to discriminate nanomaterials from other materials is prerequisite to include provisions for nanomaterials in legislation. In October 2011 the European Commission published the 'Recommendation on the definition of a nanomaterial', primarily intended to provide unambiguous criteria to identify materials for which special regulatory provisions might apply, but also to promote consistency on the interpretation of the term 'nanomaterial'. In this paper, the current status of various regulatory frameworks of the European Union with regard to nanomaterials is described, and major issues relevant for regulation of nanomaterials are discussed. This will contribute to better understanding the implications of the choices policy makers have to make in further regulation of nanomaterials. Potential issues that need to be addressed and areas of research in which science can contribute are indicated. These issues include awareness on situations in which nano-related risks may occur for materials that fall outside the definition, guidance and further development of measurement techniques, and dealing with changes during the life cycle.

Knowledge gaps in risk assessment of nanosilica in food: evaluation of the dissolution and toxicity of different forms of silica.

This manuscript describes the follow-up study of our previous publication on the presence and risks of nanosilica in food. New information on the presence of nanosilica in the gastrointestinal tract is evaluated and information on nanosilica and synthetic amorphous silica (SAS) is compared to assess its relevance for risk assessment of nanosilica in food. Irrespective of whether SAS should be regarded as a nanomaterial or a non-nanoform of silica, a comparison to nanosilica is relevant to determine whether there are differences in physicochemical properties, which may lead to differences in toxicity. Based on this comparison, knowledge gaps are identified and recommendations for a targeted approach to facilitate risk assessment of nanosilica in food are given. Considering the discussion to which extent nanomaterials with (slightly) different physicochemical characteristics can be grouped for risk assessment--the sameness issue--actual exercises as presented in this manuscript are highly relevant for bringing this discussion forward.

Calcium absorption from fortified ice cream formulations compared with calcium absorption from milk.

OBJECTIVE: Optimal bone mass in early adulthood is achieved through appropriate diet and lifestyle, thereby protecting against osteoporosis and risk of bone fracture in later life. Calcium and vitamin D are essential to build adequate bones, but calcium intakes of many population groups do not meet dietary reference values. In addition, changes in dietary patterns are exacerbating the problem, thereby emphasizing the important role of calcium-rich food products. We have designed a calcium-fortified ice cream formulation that is lower in fat than regular ice cream and could provide a useful source of additional dietary calcium. Calcium absorption from two different ice cream formulations was determined in young adults and compared with milk. SUBJECTS/SETTING: Sixteen healthy volunteers (25 to 45 years of age), recruited from the general public of The Netherlands, participated in a randomized, reference-controlled, double-blind cross-over study in which two test products and milk were consumed with a light standard breakfast on three separate occasions: a standard portion of ice cream (60 g) fortified with milk minerals and containing a low level (3%) of butter fat, ice cream (60 g) fortified with milk minerals and containing a typical level (9%) of coconut oil, and reduced-fat milk (1.7% milk fat) (200 mL). Calcium absorption was measured by the dual-label stable isotope technique. STATISTICAL ANALYSIS: Effects on calcium absorption were evaluated by analysis of variance. RESULTS: Fractional absorption of calcium from the 3% butterfat ice cream, 9% coconut oil ice cream, and milk was 26%+/-8%, 28%+/-5%, and 31%+/-9%, respectively, and did not differ significantly (P=0.159). CONCLUSIONS: Results indicate that calcium bioavailability in the two calcium-fortified ice cream formulations used in this study is as high as milk, indicating that ice cream may be a good vehicle for delivery of calcium.

Antioxidant intervention in rheumatoid arthritis: results of an open pilot study.

There is evidence that reactive oxygen species play a causal role in auto-immune diseases, such as rheumatoid arthritis (RA). Despite the supporting evidence for a beneficial effect of antioxidants on clinical characteristics of RA, the right balance for optimal effectiveness of antioxidants is largely unknown. To determine the potential beneficial effects of an antioxidant intervention on clinical parameters for RA, an open pilot study was designed. Eight non-smoking female patients with rheumatoid factor + RA and a Disease Activity Score (DAS 28) higher than 2.5 were enrolled in the study. Patients had to be receiving stable non-steroidal anti-inflammatory drug treatment and/or 'second line' medication for at least 3 months. The pilot group consumed 20 g of antioxidant-enriched spread daily during a period of 10 weeks. The intervention was stopped after 10 weeks and was followed by a 'wash-out' period of 4 weeks. At t = 0, t = 10 weeks and t = 14 weeks, patients' condition was assessed by means of DAS. In addition, standard laboratory analyses were performed, and blood-samples for antioxidants were taken. The antioxidant-enriched spread was well tolerated. All laboratory measures of inflammatory activity and oxidative modification were generally unchanged. However, the number of swollen and painful joints were significantly decreased and general health significantly increased, as reflected by a significantly improved (1.6) DAS at t = 10 weeks. The antioxidant effect was considered beneficial as, compared to the scores at t = 0, the DAS significantly reduced at t = 10 weeks. Increase of the DAS (0.7) after the "wash-out period" at t = 14 confirmed a causal relation between changes in clinical condition and antioxidants. This open pilot study aimed to assess the clinical relevance of an antioxidant intervention as a first step in assessing potential beneficial effects of antioxidants on rheumatoid arthritis. These conclusions need to be validated in a larger controlled study population.

Consumption of both black tea and green tea results in an increase in the excretion of hippuric acid into urine.

BACKGROUND: A major portion of the catechins in green tea is not absorbed in the small intestine. Bacteria in the colon convert nonabsorbed catechins into simpler phenolic compounds, which may also be absorbed. During the production of black tea, most catechins are polymerized to complex molecules called thearubigins. Little is known about the microbial degradation of these complex polyphenols, but hippuric acid has been identified as a major excretion product associated with black tea consumption. OBJECTIVE: To investigate whether green tea and black tea have the same metabolic fate in humans. DESIGN: Seventeen healthy male volunteers were studied with a randomized, full-crossover design. Each intervention period lasted 4 d, ie, a 2-d run-in period with a low-polyphenol diet followed by a 2-d treatment period. Volunteers consumed a daily dose of 6 g green tea solids, 6 g black tea solids, or 360 mg caffeine. Intervention periods were separated by a 10-d washout period. Twenty-four-hour urine samples were collected during the second day of each treatment period. Hippuric acid was analyzed with HPLC-tandem mass spectrometry. RESULTS: The mean excretion of urinary hippuric acid during black tea and green tea consumption was 3.75 +/- 0.28 mmol/24 h and 4.22 +/- 0.28 mmol/24 h, respectively (95% CI for the difference: -0.37 to +1.30 mmol/24 h). The hippuric acid excretion during the control treatment was much lower (1.89 +/- 0.28 mmol/24 h; P < 0.0001, compared with both black tea and green tea). CONCLUSION: The ingestion of either green tea or black tea results in a major increase in the excretion of hippuric acid into urine.

Differential effects of green tea-derived catechin on developing versus established atherosclerosis in apolipoprotein E-null mice.

BACKGROUND: Oxidative stress has been implicated in vascular injury and atherogenesis, and antioxidant treatment has shown favorable results in preclinical studies. Despite this, antioxidant therapy has failed to show benefit in clinical trials. Failure of antioxidants in clinical trials may be partly because such therapy is started after atherosclerosis is already well established, whereas the benefits in animal models may be results from early initiation of antioxidants while atherosclerosis is still evolving. METHODS AND RESULTS: To test this hypothesis, we evaluated the effect of epigallocatechin gallate (EGCG), the main antioxidant derived from green tea, on evolving and established atherosclerotic lesions in hypercholesterolemic apolipoprotein E-null mice. Established native aortic atherosclerotic lesions and evolving atherosclerotic lesions produced by periadventitial cuff injury to carotid arteries were assessed in mice after 21 and 42 days of treatment with daily intraperitoneal injections of EGCG (10 mg/kg) or PBS. EGCG treatment resulted in an increase in the antioxidant capacity in local vascular tissue and systemic circulation and reduced vascular smooth muscle cell proliferation and redox-sensitive gene activation in vitro. EGCG reduced cuff-induced evolving atherosclerotic plaque size at 21 and 42 days by 55% and 73%, respectively, compared with PBS treatment (P<0.05). Conversely, EGCG had no effect on established lesions in the aortic sinuses or the rest of the aorta. CONCLUSIONS: Our data suggest that antioxidant EGCG differentially reduces evolving atherosclerotic lesions without influencing established atherosclerosis in the apolipoprotein E-null mice.