Dietary mycotoxin exposure and human health risks: A protocol for a systematic review

BACKGROUND

Mycotoxins are toxic fungal secondary metabolites that contaminate a wide spectrum of essential foods worldwide, such as grain-based products, nuts and spices, causing adverse health effects pertaining to their carcinogenic, nephrotoxic and hepatotoxic nature, among others.

AIM

The aim of this systematic review (SR) is to systematically search for, appraise and synthesize primary research evidence to identify what is known about dietary mycotoxin-related health effects and what remains unknown, as well as the uncertainty around findings and the recommendations for the future.

SEARCH STRATEGY AND ELIGIBILITY CRITERIA

Search strategies, as well as eligibility criteria were structured according to a predefined PECO (population, exposure, comparison, and outcome) research question and developed in an iterative scoping process. Several bibliographic databases, including Embase, Cochrane Library, Pubmed, Web of Science Core Collection and Scopus, will be searched. Primary research on any measured or modelled dietary exposure to a single or multiple mycotoxins, and adverse human health outcomes (i.e. cancer, non-carcinogenic diseases, and reproductive & developmental adverse outcomes) will be included, and references will be imported into Covidence. In vitro, ex vivo, in silico, animal and review studies, as well as expert's opinions, secondary literature, conference abstracts, presentations, posters, book chapters, dissertations and studies involving non-dietary mycotoxin exposure, will be excluded.

STUDY SELECTION

Two independent reviewers will screen titles and abstracts, and review full-texts. Any disagreements will be resolved by a third reviewer based on two-third majority.

DATA EXTRACTION

Data from retained eligible studies will be extracted by the principal reviewer, and peer-checked by a second reviewer.

STUDY QUALITY ASSESSMENT

Eligible studies will be evaluated for risk of bias (Overall High-Quality Assessment Tool, OHAT) and certainty of evidence (Grading of Recommendations Assessment, Development and Evaluation, GRADE).

EVIDENCE SYNTHESIS

A detailed summary of the included studies will be provided within a tabular format and narratively discussed. Heat maps will be constructed to provide information on available knowledge (gaps), and a meta-analysis may be performed based on the variability in predefined PECO elements and depending on the heterogeneity of studies.

CONCLUSION

This protocol describes the methodology for the conduct of a SR on mycotoxin-related human health risks, that could guide future research and inform regulatory decisions, as emphasized by the European Commission within the field of regulatory risk assessment for emerging chemicals.

Correlation of the volume of ectopic pregnancy and MTX therapy outcome: a retrospective cohort study

OBJECTIVE

To investigate a possible correlation between the volume of the tubal ectopic pregnancy (EP) measured by vaginal-ultrasound (VUS) and methotrexate (MTX) therapy outcome.

STUDY DESIGN

Data of EP volume measured by one expert-sonographer, viability, clinical symptoms, previous IVF/insemination, follow-up of β-hCG and progesterone levels, and treatment of EP was collected of 100 patients with sonographically diagnosed EP, who attended the Department of Obstetrics and Gynecology of the Medical University Vienna between March 2008 and September 2011.

RESULTS

The mean volume of EP (mVol.) in the group with successful MTX therapy (n = 38) was 5.11 ml, 95%CI [2.4; 7.8] with a median 3.2 ml, IQR [5.0], in the group with unsuccessful MTX treatment (n = 11) it was 15.24 ml, 95%CI [-2.6; 33.1], with a median 4.4 ml, IQR [11.4]. We could observe a trend towards a lower mVol. in the successful MTX group (5.11 ml vs. 15.24 ml). We could not show a significant correlation (u-test p = 0.208).

CONCLUSION

A clear tendency was observed towards a lower mVol. in the successful MTX therapy group, but we could not verify a statistically significant correlation of volume of EP and MTX therapy outcome most likely due to the small sample size. This was the first study investigating the correlation of volume of EP and MTX therapy outcome as principal question.

Analysis of mechanisms contributing to AraC-mediated chemoresistance and re-establishment of drug sensitivity by the novel heterodinucleoside phosphate 5-FdUrd-araC

Chemoresistance is a biological response of cells to survive toxic stress. During cancer treatment the development of chemoresistance is a major problem. The mechanisms how cells become insensitive, and which downstream pathways are affected are not completely understood. Since it has not been well analysed which and how many regulative disorders are subsummised under the term "chemoresistance", we examined and measured arabinosylcytosine (AraC)-mediated desensitation of two mechanisms relevant for tissue homeostasis, cell cycle inhibition and apoptosis induction. MCF-7 cells harbouring ectopic mutated p53 were suitable for this investigation because they activated these mechanisms subsequently and became insensitive to AraC with regard to cell cycle inhibition and apoptosis induction. The major causal mechanism of acquired resistance against AraC was most likely through the inhibition of the first step of AraC phosphorylation within the cell, which is rate limiting for its activation. With regard to cell cycle inhibition AraC-resistant cells were also resistant against 5-fluorodeoxyuridine (5-FdUrd), but fully responsive to 5-FdUrd-induced apoptosis, evidencing that cell cycle and apoptosis are independent of each other. Apoptosis correlated with AIF-activation and was independent of Caspase 7, whereas cell cycle inhibition correlated with cyclinD1 expression but not with induction of p21 or p27. The phosphate conjugated 5-FdUrd-araC heterodimer (5-Fluoro-2'-desoxyuridylyl-(3'-->5')-Arabinocytidine), which is a prodrug of AraC-monophosphate, reactivated AIF and down-regulated cyclin D1 in AraC-resistant cells and circumvented resistance to apoptosis and to cell cycle inhibition. Also, cells which were resistant to 5-FdUrd or doxorubicin were sensitive to 5-FdUrd-araC. This investigation demonstrates that chemoresistance affects apoptosis induction and cell cycle inhibition independently and that detailed knowledge about the affected downstream pathways would enable the design of targeted intervention with small molecules to restore chemosensitivity.

Amino Acid analysis of intellan, a herbal product used in enhancing brain function

Analysis of the drug "INTELLAN" and two reputed plants i.e. Centella asiatica and Herpestis monniera used in the preparation of the drug reveals that glutamic and aspartic acids are present in high concentration in the drug and are also required by brain in high concentration to keep itself in higher gears. Both these amino acids are used as neurotransmitters and also in stabilizing and stimulating the activities of brain, thus resulting in better performance.