Characterization of lactic acid bacteria isolated from human breast milk and their bioactive metabolites with potential application as a probiotic food supplement.

The probiotic properties of twenty-five lactic acid bacteria (LAB) isolated from human breast milk were investigated considering their resistance to gastrointestinal conditions and proteolytic activity. Seven LAB were identified and assessed for auto- and co-aggregation capacity, antibiotic resistance, and behavior during in vitro gastrointestinal digestion. Three Lacticaseibacillus strains were further evaluated for antifungal activity, metabolite production (HPLC-Q-TOF-MS/MS and GC-MS/MS) and proteolytic profiles (SDS-PAGE and HPLC-DAD) in fermented milk, whey, and soy beverage. All strains resisted in vitro gastrointestinal digestion with viable counts higher than 7.9 log10 CFU mL-1 after the colonic phase. Remarkable proteolytic activity was observed for 18/25 strains. Bacterial auto- and co-aggregation of 7 selected strains reached values up to 23 and 20%, respectively. L. rhamnosus B5H2, L. rhamnosus B9H2 and L. paracasei B10L2 inhibited P. verrucosum, F. verticillioides and F. graminearum fungal growth, highlighting L. rhamnosus B5H2. Several metabolites were identified, including antifungal compounds such as phenylacetic acid and 3-phenyllactic acid, and volatile organic compounds produced in fermented milk, whey, and soy beverage. SDS-PAGE demonstrated bacterial hydrolysis of the main milk (caseins) and soy (glycines and beta-conglycines) proteins, with no apparent hydrolysis of whey proteins. However, HPLC-DAD revealed alpha-lactoglobulin reduction up to 82% and 54% in milk and whey, respectively, with L. rhamnosus B5H2 showing the highest proteolytic activity. Overall, the three selected Lacticaseibacillus strains demonstrated probiotic capacity highlighting L. rhamnosus B5H2 with remarkable potential for generating bioactive metabolites and peptides which are capable of promoting human health.

Extensive folliculitis and abscesses with a sporotrichoid distribution in a parenteral drug user.

We present the case of a 53-year-old Caucasian man with a history of intravenous drug use who presented with fever and multiple pustules predominantly affecting hairy areas of the body, with no clinical improvement despite previous antibiotic treatment. Culture of the pustules confirmed Candida albicans infection and histological examination of skin biopsies revealed suppurative granulomas compatible with candidomycetic folliculitis. The patient was successfully treated with systemic antifungals and discharged with resolution of symptoms. Candidomycetic folliculitis is a condition typically associated with brown heroin consumption due to the use of acidic solvent that promotes Candida growth. Clinical manifestations include fever followed by skin lesions, with possible systemic involvement if untreated. Extensive folliculitis with associated fever in an IVDU should raise suspicion of this pathology since early diagnosis and appropriate treatment are crucial to prevent complications.

Applying a modified systematic review and integrated assessment framework (SYRINA) - a case study on triphenyl phosphate.

This work presents a case study in applying a systematic review framework (SYRINA) to the identification of chemicals as endocrine disruptors. The suitability and performance of the framework is tested with regard to the widely accepted World Health Organization definition of an endocrine disruptor (ED). The endocrine disrupting potential of triphenyl phosphate (TPP), a well-studied flame retardant reported to exhibit various endocrine related effects was assessed. We followed the 7 steps of the SYRINA framework, articulating the research objective via Populations, Exposures, Comparators, Outcomes (PECO) statements, performed literature search and screening, conducted study evaluation, performed data extraction and summarized and integrated the evidence. Overall, 66 studies, consisting of in vivo, in vitro and epidemiological data, were included. We concluded that triphenyl phosphate could be identified as an ED based on metabolic disruption and reproductive function. We found that the tools used in this case study and the optimizations performed on the framework were suitable to assess properties of EDs. A number of challenges and areas for methodological development in systematic appraisal of evidence relating to endocrine disrupting potential were identified; significant time and effort were needed for the analysis of in vitro mechanistic data in this case study, thus increasing the workload and time needed to perform the systematic review process. Further research and development of this framework with regards to grey literature (non-peer-reviewed literature) search, harmonization of study evaluation methods, more consistent evidence integration approaches and a pre-defined method to assess links between adverse effect and endocrine activity are recommended. It would also be advantageous to conduct more case studies for a chemical with less data than TPP.

Aflatoxin B1 and ochratoxin A reduction by Lactobacillus spp. during bread making.

BACKGROUND: Aflatoxin B1 (AFB1) and ochratoxin A (OTA) are among the most important mycotoxins with common presence in bread and bakery products. Biological detoxification of mould food spoilage and mycotoxin contamination by lactic acid bacteria (LABs) exhibits high potential on a cost-effective and large scale. In this work, the effect of Lactobacillus strains isolated from goat milk whey on reducing AFB1 and OTA during bread making was evaluated by the determination of mycotoxin reduction potential of 12 LAB strains after 72 h incubation in De Man-Rogosa-Sharpe (MRS) broth (37 °C). The most effective LABs were lyophilized and added as ingredient in bread formulation, analysing mycotoxins by high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry after bread fermentation and baking. RESULTS: AFB1 was reduced in MRS broth by seven LABs (11-35%), highlighting Lactobacillus plantarum B3 activity; while all LABs reduced OTA (12-40%) with L. plantarum B3 and Lactobacillus paracasei B10 as the most active strains. Both LABs were lyophilized and added in contaminated bread with and without yeast, reaching AFB1 and OTA reductions up to 27% and 32% respectively in dough and up to 55% and 34% respectively in bread. CONCLUSION: The selected strains significantly reduced AFB1 and OTA during bread fermentation, pointing to a potential biocontrol strategy for mycotoxins detoxification in bread and bakery products. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Biomonitoring of Multiple Mycotoxins in Urine by GC-MS/MS: A Pilot Study on Patients with Esophageal Cancer in Golestan Province, Northeastern Iran.

A pilot study to investigate the occurrence of 10 mycotoxins (deoxynivalenol, DON; 3-acetyldeoxynivalenol, 3-ADON; 15-acetyldeoxynivalenol, 15-ADON; fusarenon-X, FUS-X; diacetoxyscirpenol, DAS; nivalenol, NIV; neosolaniol, NEO; zearalenone, ZON; zearalanone, ZAN; T-2 toxin, T-2; and HT-2 toxin, HT-2) in esophageal cancer patients was performed with the urinary biomarkers approach in Golestan, Iran. Urine multimycotoxin analysis was performed by dispersive liquid-liquid microextraction and gas chromatography-tandem mass spectrometry (GC-MS/MS) analysis, and values were normalized with urinary creatinine (µg/g). Four mycotoxins, namely NEO (40%), HT-2 (17.6%), DON (10%), and HT-2 (5.8%), were detected in the analyzed urine samples. DON was only detected in the control group (5.09 µg/g creatinine), while T-2 (44.70 µg/g creatinine) was only present in the esophageal cancer group. NEO and HT-2 were quantified in both control and case groups, showing average of positive samples of 9.09 and 10.45 µg/g creatinine for NEO and 16.81 and 29.09 µg/g creatinine for HT-2, respectively. Mycotoxin co-occurrence was observed in three samples as binary (NEO/HT-2 and T-2/HT-2) and ternary (DON/NEO/HT-2) combinations, reaching total concentrations of 44.58, 79.13, and 30.04 µg/g creatinine, respectively. Further investigations are needed to explore a causal association between mycotoxin contamination and esophageal cancer. For this pilot study in Golestan, the low sample size was a very limiting factor.

Assessment of the endocrine disrupting properties of bisphenol AF: a case study applying the European regulatory criteria and guidance.

BACKGROUND: Scientific criteria to identify endocrine disruptors (ED) was recently implemented for plant protection products (PPP) and biocidal products (BP). A guidance document has been published by ECHA and EFSA in the context of ED criteria for PPPs and BPs. METHODS: In the present work, a case study was performed on Bisphenol AF (BPAF) to explore the application of the EU criteria and EFSA/ECHA guidance document for the ED assessment of a non-pesticide chemical regulated under REACH. A data dossier was built by a systematic literature search (Web of Science, Pubmed, Embase; n = 511), title/abstract screening (n = 124) and full text examination (n = 88). All the information was extracted and systematically reported for 309 parameters (100 for adversity; 209 for endocrine activity). The reliability of studies was assessed (SciRAP tool). RESULTS: Data were synthesized into 96 lines of evidence for adversity (n = 57), and endocrine activity (n = 39); and assessed by weight of evidence methodology. The initial analysis of the evidence indicated EATS-mediated adversity in mammals, therefore a mode of action (MoA) was postulated for both male and female adult exposure. Female MoA included estrogen receptor activation and altered steroidogenesis leading to ovarian dysfunction, altered estrous cycling and impaired female fertility. Male MoA was initiated by androgen receptor inhibition and altered steroidogenesis leading to dysfunction of male reproductive organs and impaired male fertility. CONCLUSIONS: The overall conclusion of the ED assessment indicated that BPAF meets the ED criteria for human health. The steps described in the ED guidance document were successfully completed, resulting in a thorough, structured and transparent identification of BPAF as an ED. Advantages and limitations of applying the ED criteria and guidance for a REACH chemical are discussed.

Bioaccessibility Study of Aflatoxin B1 and Ochratoxin A in Bread Enriched with Fermented Milk Whey and/or Pumpkin.

The presence of mycotoxins in cereals and cereal products remains a significant issue. The use of natural ingredients such as pumpkin and whey, which contain bioactive compounds, could be a strategy to reduce the use of conventional chemical preservatives. The aim of the present work was to study the bioaccessibility of aflatoxin B1 (AFB1) and ochratoxin (OTA) in bread, as well as to evaluate the effect of milk whey (with and without lactic acid bacteria fermentation) and pumpkin on reducing mycotoxins bioaccessibility. Different bread typologies were prepared and subjected to an in vitro digestion model. Gastric and intestinal extracts were analyzed by HPLC-MS/qTOF and mycotoxins bioaccessibility was calculated. All the tested ingredients but one significantly reduced mycotoxin intestinal bioaccessibility. Pumpkin powder demonstrated to be the most effective ingredient showing significant reductions of AFB1 and OTA bioaccessibility up to 74% and 34%, respectively. Whey, fermented whey, and the combination of pumpkin-fermented whey showed intestinal bioaccessibility reductions between 57-68% for AFB1, and between 11-20% for OTA. These results pointed to pumpkin and milk whey as potential bioactive ingredients that may have promising applications in the bakery industry.

A validated search filter for the identification of endocrine disruptors based on the ECHA/EFSA guidance recommendations.

A guidance document for the identification of endocrine disruptors (EDs) in the regulatory assessment of plant protection products (PPP) and biocidal products (BP) has been published by the European Chemical Agency (ECHA) and the European Food Safety Authority (EFSA). The ECHA/EFSA guidance, mainly addressing EATS (estrogen, androgen, thyroid, steroidogenesis) modalities, is intended to guide applicants and assessors of the competent regulatory authorities on the implementation of the scientific criteria for the determination of ED properties pursuant to the recently implemented PPP (EU 2018/605) and BP (EU 2017/2100) EU Regulations. In this study, a search filter for targeted literature search in context of assessing if a substance can be identified as an ED relevant for human health was developed and validated. Development of the search filter was based on the search strategy presented in the ECHA/EFSA guidance and using the estrogenic chemical Bisphenol AF (BPAF) as a model substance. Information specialists from two independent institutions developed refined search filters based on the suggested original search strategy published (ECHA/EFSA guidance - Appendix F). Articles identified by a systematic literature search for BPAF were screened for relevance with inclusion and exclusion criteria by two independent reviewers obtaining positive (relevant) and negative (irrelevant) controls. The developed search filter was quantitatively evaluated in terms of sensitivity, specificity and precision based on the positive and negative controls. The developed filter was then validated for T modality by its application to the known thyroid-disruptor perchlorate. The result is a sensitive search filter with sufficient specificity, which can be applied for all chemicals where a targeted literature search is needed to assess and identify ED properties of chemicals with relevance for humans. Future application of the filter to a broader range of chemicals may identify further points of improvement.

Melatonin in the seasonal response of the aphid Acyrthosiphon pisum.

Aphids display life cycles largely determined by the photoperiod. During the warm long-day seasons, most aphid species reproduce by viviparous parthenogenesis. The shortening of the photoperiod in autumn induces a switch to sexual reproduction. Males and sexual females mate to produce overwintering resistant eggs. In addition to this full life cycle (holocycle), there are anholocyclic lineages that do not respond to changes in photoperiod and reproduce continuously by parthenogenesis. The molecular or hormonal events that trigger the seasonal response (i.e., induction of the sexual phenotypes) are still unknown. Although circadian synthesis of melatonin is known to play a key role in vertebrate photoperiodism, the involvement of the circadian clock and/or of the hormone melatonin in insect seasonal responses is not so well established. Here we show that melatonin levels in the aphid Acyrthosiphon pisum are significantly higher in holocyclic aphids reared under short days than under long days, while no differences were found between anholocyclic aphids under the same conditions. We also found that melatonin is localized in the aphid suboesophageal ganglion (SOG) and in the thoracic ganglionic mass (TGM). In analogy to vertebrates, insect-type arylalkylamine N-acetyltransferases (i-AANATs) are thought to play a key role in melatonin synthesis. We measured the expression of four i-AANAT genes identified in A. pisum and localized two of them in situ in the insect central nervous systems (CNS). Levels of expression of these genes were compatible with the quantities of melatonin observed. Moreover, like melatonin, expression of these genes was found in the SOG and the TGM.

Transcriptional study after Beauvericin and Enniatin B combined exposure in Jurkat T cells.

Simultaneous mycotoxins toxicity is complex and non-predictable based on their individual toxicities. Beauvericin and Enniatins are emerging mycotoxins highly co-occurrent in food and feed, and their cytotoxicity has been reported in several human cell lines. RNA-seq studies of individual exposure in Jurkat cells demonstrated human genome perturbation mainly affecting mitochondrial pathways, however, both mycotoxins showed differences between their toxic responses. This study investigates the transcriptional effects of combined exposure to Beauvericin and Enniatin B (1:1) (0.1, 0.5, 1.5 µM; 24 h) in Jurkat cells by qPCR on 30 selected target genes (10 mitochondrial, 20 nuclear). Gene expression after combined and individual exposures were compared and functional data analysis (ToxPi) on the most relevant biological processes (cycle and apoptosis regulation; cholesterol metabolism and transport; cellular signaling transduction; cellular stress responses; immune regulation; protein metabolism; retinoic acid metabolism; transcription regulation) was applied to RNA-seq data from individual exposure (1.5, 3, 5 µM; 24 h; Jurkat cells). Transcriptional changes, especially at mitochondrial level, were observed after Beauvericin-Enniatin B co-exposure including down-regulation of antioxidant activity related genes. Different expression patterns between combined and individual exposures were identified. ToxPi analysis confirmed different dose-dependent relationship profiles between these two mycotoxins after individual exposure.

Assessment of the endocrine disrupting properties of Bisphenol AF according to the EU criteria and ECHA/EFSA guidance.

Endocrine disruptors (EDs) are exogenous compounds that interfere with the hormone system, affecting human health and environment. Specific legislative obligations have been introduced in the European Union (EU) to gradually eliminate EDs in water, industrial chemicals and pesticides. However, identification of EDs is the first and essential step towards regulation and appropriate risk management. Scientific criteria and guidance for ED assessment have recently been established for pesticides in the EU. In this project, the ED properties of the non-pesticide chemical Bisphenol AF (BPAF), analogue and potential substitute of Bisphenol A were evaluated by the application of the EU criteria and guidance in the frame of human health risk assessment. A data dossier was built by a systematic literature review (WOS, Scopus, Pubmed, Embase), title/abstract screening (RAYYAN) and full-text examination. All relevant information was extracted and systematically reported, and reliability and relevance of data were assessed (SciRAP). Data were synthesised into lines of evidence for (i) endocrine activity, (ii) adversity and (iii) general toxicity, and weight of evidence evaluation was applied. The initial analysis of the evidence showed potential endocrine adverse effects and endocrine activity, meeting the ED criteria and leading the assessment to the mode of action (MoA) analysis. The biological plausibility of the link between the adverse effects and the endocrine activity was investigated based on current scientific knowledge. Empirical support for dose-response and temporal concordance was evaluated, and the key events were assessed in terms of essentiality, consistency, analogy and specificity. Finally, an overall conclusion of the ED properties of BPAF was drawn. The EU criteria and guidance for EDs assessment were successfully applied to BPAF demonstrating its endocrine activity and adversity based on weight of evidence methodology and MoA analysis. The Fellow greatly increased her knowledge and hands-on experience on ED assessment in the EU regulatory context contributing to implement transparency and structure in health risk assessment.

Mycotoxin Analysis of Human Urine by LC-MS/MS: A Comparative Extraction Study.

The lower mycotoxin levels detected in urine make the development of sensitive and accurate analytical methods essential. Three extraction methods, namely salting-out liquid-liquid extraction (SALLE), miniQuEChERS (quick, easy, cheap, effective, rugged, and safe), and dispersive liquid-liquid microextraction (DLLME), were evaluated and compared based on analytical parameters for the quantitative LC-MS/MS measurement of 11 mycotoxins (AFB1, AFB2, AFG1, AFG2, OTA, ZEA, BEA, EN A, EN B, EN A1 and EN B1) in human urine. DLLME was selected as the most appropriate methodology, as it produced better validation results for recovery (79-113%), reproducibility (RSDs < 12%), and repeatability (RSDs < 15%) than miniQuEChERS (71-109%, RSDs <14% and <24%, respectively) and SALLE (70-108%, RSDs < 14% and < 24%, respectively). Moreover, the lowest detection (LODS) and quantitation limits (LOQS) were achieved with DLLME (LODs: 0.005-2 µg L-1, LOQs: 0.1-4 µg L-1). DLLME methodology was used for the analysis of 10 real urine samples from healthy volunteers showing the presence of ENs B, B1 and A1 at low concentrations.

Studies on the Presence of Mycotoxins in Biological Samples: An Overview.

Mycotoxins are fungal secondary metabolites with bioaccumulation levels leading to their carry-over into animal fluids, organs, and tissues. As a consequence, mycotoxin determination in biological samples from humans and animals has been reported worldwide. Since most mycotoxins show toxic effects at low concentrations and considering the extremely low levels present in biological samples, the application of reliable detection methods is required. This review summarizes the information regarding the studies involving mycotoxin determination in biological samples over the last 10 years. Relevant data on extraction methodology, detection techniques, sample size, limits of detection, and quantitation are presented herein. Briefly, liquid-liquid extraction followed by LC-MS/MS determination was the most common technique. The most analyzed mycotoxin was ochratoxin A, followed by zearalenone and deoxynivalenol-including their metabolites, enniatins, fumonisins, aflatoxins, T-2 and HT-2 toxins. Moreover, the studies were classified by their purpose, mainly focused on the development of analytical methodologies, mycotoxin biomonitoring, and exposure assessment. The study of tissue distribution, bioaccumulation, carry-over, persistence and transference of mycotoxins, as well as, toxicokinetics and ADME (absorption, distribution, metabolism and excretion) were other proposed goals for biological sample analysis. Finally, an overview of risk assessment was discussed.

Mycotoxin contamination in laboratory rat feeds and their implications in animal research.

Compound feed is particularly vulnerable to multi-mycotoxin contamination. A method for the determination of 12 mycotoxins; enniatins A, A1, B, B1; aflatoxins B1, B2, G1, G2; OTA; ZEA; T-2 and HT-2 by liquid chromatography-tandem mass spectrometry has been developed and applied for the analysis of laboratory rat commercial feeds. The method trueness was checked by recovery assays at three different spiked levels (n = 9). Recoveries ranged from 73% to 112%, and the intra-day and inter-day precision were lower than 9% and 13%, respectively. Limits of quantitation were lower than 15 µg/kg. Twenty-seven laboratory rats feed samples showed multi-contamination by at least three up to six different mycotoxins. ENNs B and B1, followed by ZEA were the most prevalent mycotoxins. T-2, HT-2, and OTA were not detected. ZEA showed the highest concentration levels reaching 492 µg/kg. The results underline the importance of implementing mycotoxin regular surveillance programs for laboratory animal feeds.

Determination of melatonin in Acyrthosiphon pisum aphids by liquid chromatography-tandem mass spectrometry.

Melatonin is a hormone mainly involved in the regulation of circadian and seasonal rhythms in both invertebrates and vertebrates. Despite the identification of melatonin in many insects, its involvement in the insect seasonal response remains unclear. A liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed for melatonin analysis in aphids (Acyrthosiphon pisum) for the first time. After comparing two different procedures and five extraction solvents, a sample preparation procedure with a mixture of methanol/water (50:50) was selected for melatonin extraction. The method was validated by analyzing melatonin recovery at three spiked concentrations (5, 50 and 100 pg/mg) and showed satisfactory recoveries (75-110%), and good repeatability, expressed as relative standard deviation (<10%). Limits of detection (LOD) and quantitation (LOQ) were 1 pg/mg and 5 pg/mg, respectively. Eight concentration levels were used for constructing the calibration curves which showed good linearity between LOQ and 200 times LOQ. The validated method was successfully applied to 26 aphid samples demonstrating its usefulness for melatonin determination in insects. This is -to our knowledge- the first identification of melatonin in aphids by LC-MS/MS.

Analysis of trichothecenes in laboratory rat feed by gas chromatography-tandem mass spectrometry.

A method for the determination of seven trichothecenes, neosolaniol (NEO), diacetoxyscirpenol (DAS), deoxynivalenol (DON), nivalenol (NIV), fusarenon-X (FUS-X), 3-acetyldeoxynivalenol (3-ADON) and 15-acetyldeoxynivalenol (15-ADON), in laboratory rat feed by GC-MS/MS was developed. Sample extraction and purification was performed by an acidified mixture of acetonitrile/water (80-20% v/v). Limits of quantitation (LOQs) were between 1 and 10 µg kg(-1) for all studied trichothecenes. Eight concentration levels between the LOQ and 100 × LOQ were used for the calibration curves. Matrix-matched calibration was used for quantitation purposes to compensate the detector signal enhancement obtained for all the analytes. The method accuracy was evaluated by recovery assays at three concentration levels, 25, 50 and 100 µg kg(-1) (n = 9). Recoveries ranged from 62% to 97% and precision, expressed as intra- and inter-day relative standard deviations, was evaluated for all compounds. The validated method was successfully applied to the analysis of 35 laboratory rat feed samples showing mycotoxin contamination in 66% of the samples. DON was the most prevalent trichothecene followed by 15-ADON, NIV and 3-ADON. The maximum DON concentration reached in real samples was 2156 ± 4.3 µg kg(-1), while NEO, DAS and FUS-X were not detected in any sample. Multi-contamination by at least two mycotoxins was observed in 17% of the analysed feed samples.

Quantitation of enniatins in biological samples of Wistar rats after oral administration by LC-MS/MS.

The emerging Fusarium mycotoxins enniatins (ENNs) have diverse biological properties, mainly due to their ionophoric activity, and represent a potential risk to human and animal health since they are commonly found in food and feed. In vivo toxicity studies are scarce and limited to the major mycotoxins. Until now, any method for the simultaneous analysis of these compounds in plasma, serum and feces from rat has been reported. A method for the extraction and determination of ENNs A, A1, B and B1 from Wistar rat samples by liquid chromatography tandem mass spectrometry has been developed. The method was successfully validated with satisfactory recoveries (70-106%), good intraday (<10%) and interday (<20%) precision, expressed as relative standard deviation, and good linearity between limits of quantitation (LOQ) and 100 times LOQ. Limits of detection (LOD) and LOQ were ≤1 and ≤10 ng/ml, respectively. The validated method was applied for the analysis of biological Wistar rat samples that were administered a mixture of ENNs containing 1.19, 2.16, 1.03 and 1.41 mg/kg body weight of ENN A, A1, B and B1, respectively. Blood, urine and feces samples collected every 2 h during the 8-h duration of the experiment were analyzed. The administered dose of the mixture of ENNs did not cause observable adverse effects on the animals. ENNs concentrations detected in serum and urine were below LOQs. The four ENNs were detected in feces reaching the maximum concentration at 6 h after administration.

A preliminary study in Wistar rats with enniatin A contaminated feed.

A 28-day repeated dose preliminary assay, using enniatin A naturally contaminated feed through microbial fermentation by a Fusarium tricinctum strain, was carried out employing 2-month-old female Wistar rats as in vivo experimental model. In order to simulate a physiological test of a toxic compound naturally produced by fungi, five treated animals were fed during 28 days with fermented feed. As control group, five rats were fed with standard feed. At the 28th day, blood samples were collected for biochemical analysis and the gastrointestinal tract, liver and kidneys were removed from each rat for enniatin A detection and quantitation. Digesta were collected from stomach, duodenum, jejunum, ileum and colon. Enniatin A present in organs and in biological fluids was analyzed by liquid chromatography-diode array detector (LC-DAD) and confirmed by LC-mass spectrometry linear ion trap (MS-LIT); also several serum biochemical parameters and a histological analysis of the duodenal tract were performed. No adverse effects were found in any treated rat at the enniatin A concentration (20.91 mg/kg bw/day) tested during the 28-day experiment. Enniatin A quantitation in biological fluids ranged from 1.50 to 9.00 mg/kg, whereas in the gastrointestinal organs the enniatin A concentration ranged from 2.50 to 23.00 mg/kg. The high enniatin A concentration found in jejunum liquid and tissue points to them as an absorption area. Finally, two enniatin A degradation products were identified in duodenum, jejunum and colon content, probably produced by gut microflora.

Sampling expansions for three-dimensional light amplitude distribution in the vicinity of an axial image point: comment.

Landgrave and Berriel-Valdos presented axial and radial sampling expansions for three-dimensional light amplitude distribution around the Gaussian focal point. [J. Opt. Soc. Am. A 14, 2962 (1997)]. The expansions were obtained under the assumption that the pupil function was rotationally symmetric. We present a new derivation of the axial expansion that does not make use of arbitrary formal assumptions used by Landgrave and Berriel-Valdos and eliminates some faults of the derivation given by Arsenault and Boivin, who published this expansion in 1967 [J. Appl. Phys. 38, 3988 (1967)]. We also discuss generalizations of the axial expansion to the case of pupils that exhibit no symmetry with respect to the axis considered.