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Introduction: The advent of molecular typing using MIRU-VNTR mini-satellites has largely facilitated tuberculosis (TB) molecular epidemiological studies. Apart from detecting the chains of transmission and risk factors, these markers have also allowed to study the phenomena of mixed strain infections versus microevolutionary events. Methods: An initial set of Mycobacterium tuberculosis strains (n = 161) genotyped using spoligotyping and MIRU-VNTRs in Guyana and Suriname was evaluated for indications mixed strain infections (characterized by the detection of double alleles in 2 or more MIRU loci) versus “in-patient” microevolutionary events (characterized by the detection of double alleles in a single locus). Results: The present study hereby reports evidence of microevolution in 3.7% (n = 6/161) of the studied population, vs. 0.6% (n = 1/161) for mixed infection. The strains belonged to three different spoligotyping-based lineages, namely the T (SITs 44, 53, and 1081), Haarlem (SIT47), and EAI (SITs 72 and 349) lineages, while 1 isolate (SIT237) could not be assigned to any lineage. Discussion: By comparing these results on microevolutionary cases (n = 6) to 112,000 strains present in the SITVIT2 database, evidence is presented that in 2/6 cases (each case corresponding to 2 patterns due to MIRU double bands), one of the patterns corresponded to a shared type found exclusively in Suriname or Guyana. Phylogenetic analysis showed that no spoligotyping lineage in particular was more prone to microevolutionary events in this study's sample. Overall, the observations fortify the awareness regarding the existence of microevolution and polyclonal TB infections which has important implications for patient care.

The development of liquid chromatography-mass spectrometry (LC-MS)/mass spectrometry (MS) methods for the simultaneous detection and quantification of a broad spectrum of mycotoxins has facilitated the screening of a larger number of samples for contamination with a wide array of less well-known “emerging” mycotoxins and other metabolites. In this study, 83 samples of feed and feed raw materials were analysed. All of them were found to contain seven to 69 metabolites. The total number of detected metabolites amounts to 139. Fusarium mycotoxins were most common, but a number of Alternaria toxins also occurred very often. Furthermore, two so-called masked mycotoxins (i.e., mycotoxin conjugates), namely deoxynivalenol-3-glucoside (75% positives) and zearalenone-4-sulfate (49% positives), were frequently detected. Although the observed median concentrations of the individual analytes were generally in the low μg/kg range, evaluating the toxicological potential of a given sample is difficult. Toxicity data on less well-known mycotoxins and other detected metabolites are notoriously scarce, as an overview on the available information on the most commonly detected metabolites shows. Besides, the possible synergistic effects of co-occurring substances have to be considered.

Mycotoxins are secondary metabolites produced by fungi especially those belonging to the genus Aspergillus, Penicillum and Fusarium. Mycotoxin contamination can occur in all agricultural commodities in the field and/or during storage, if conditions are favourable to fungal growth. Regarding animal feed, five mycotoxins (aflatoxins, deoxynivalenol, zearalenone, fumonisins and ochratoxin A) are covered by EU legislation (regulation or recommendation). Transgressions of these limits are rarely observed in official monitoring programs. However, low level contamination by Fusarium toxins is very common (e.g., deoxynivalenol (DON) is typically found in more than 50% of the samples) and co-contamination is frequently observed. Multi-mycotoxin studies reported 75%–100% of the samples to contain more than one mycotoxin which could impact animal health at already low doses. Co-occurrence of mycotoxins is likely to arise for at least three different reasons (i) most fungi are able to simultaneously produce a number of mycotoxins, (ii) commodities can be contaminated by several fungi, and (iii) completed feed is made from various commodities. In the present paper, we reviewed the data published since 2004 concerning the contamination of animal feed with single or combinations of mycotoxins and highlighted the occurrence of these co-contaminations.

The scientific programme of the 9th International Congress “Flour-Bread ’17” and the 11th Croatian Congress of Cereal Technologists “Brašno-Kruh ’17” held from 25 to 27 October in Grand Hotel Adriatic, Opatija, Croatia, included 39 oral and 38 poster presentations. Three plenary lectures, 11 invited lectures, 19 oral presentations, three sponsor advertisement presentations, 3 interactive workshop lectures and 38 poster presentations were within one of five different Congress topics: Cereals and Cereal Product Quality, Cereal Processing Technologies, Cereals and Health, Cereal Food Safety, and Cereal Waste Management.

Nontuberculous mycobacteria (NTM) are ubiquitous environmental organisms able to cause severe opportunistic human infections. Their distribution patterns are subject to geographical variations. This study describes their isolation frequencies from clinical specimen in the three French overseas departments of the Americas, namely, Guadeloupe, Martinique, and French Guiana during 1994–2012. A total of 651 strains from as many patients (one isolate per species per patient) were analysed regarding regional isolation patterns and potential pattern changes over time. The Mycobacterium avium complex was the most common group of NTM in Guadeloupe and French Guiana. In Martinique it was the second most common after the rapidly growing mycobacteria. M. fortuitum was the most commonly isolated species in all three departments. Some species (M. kansasii, M. xenopi, and M. terrae complex) displayed a clear regional preference. Furthermore a change in isolation frequency was observed for M. intracellulare (increase) and M. kansasii (decrease) in Guadeloupe. In conclusion, marked regional differences in isolation frequencies of NTM species were observed in the study area. Results are discussed in context of variables such as study populations, risk factors, methodology employed, isolation from pulmonary versus sterile isolation sites (blood, urine, and CSF), and in vitro drug-susceptibility patterns.

Multiple-locus variable-number tandem repeat analysis (MLVA) is useful to establish transmission routes and sources of infections for various microorganisms including Mycobacterium tuberculosis complex (MTC). The recently released SITVITWEB database contains 12-loci Mycobacterial Interspersed Repetitive Units--Variable Number of Tandem DNA Repeats (MIRU-VNTR) profiles and spoligotype patterns for thousands of MTC strains; it uses MIRU International Types (MIT) and Spoligotype International Types (SIT) to designate clustered patterns worldwide. Considering existing doubts on the ability of spoligotyping alone to reveal exact phylogenetic relationships between MTC strains, we developed a MLVA based classification for MTC genotypic lineages. We studied 6 different subsets of MTC isolates encompassing 7793 strains worldwide. Minimum spanning trees (MST) were constructed to identify major lineages, and the most common representative located as a central node was taken as the prototype defining different phylogenetic groups. A total of 7 major lineages with their respective prototypes were identified: Indo-Oceanic/MIT57, East Asian and African Indian/MIT17, Euro American/MIT116, West African-I/MIT934, West African-II/MIT664, M. bovis/MIT49, M.canettii/MIT60. Further MST subdivision identified an additional 34 sublineage MIT prototypes. The phylogenetic relationships among the 37 newly defined MIRU-VNTR lineages were inferred using a classification algorithm based on a bayesian approach. This information was used to construct an updated phylogenetic and phylogeographic snapshot of worldwide MTC diversity studied both at the regional, sub-regional, and country level according to the United Nations specifications. We also looked for IS6110 insertional events that are known to modify the results of the spoligotyping in specific circumstances, and showed that a fair portion of convergence leading to the currently observed bias in phylogenetic classification of strains may be traced back to the presence of IS6110. These results shed new light on the evolutionary history of the pathogen in relation to the history of peopling and human migration.