The Phytochemical Agathisflavone Modulates miR146a and miR155 in Activated Microglia Involving STAT3 Signaling

MicroRNAs (miRs) act as important post-transcriptional regulators of gene expression in glial cells and have been shown to be involved in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease (AD). Here, we investigated the effects of agathisflavone, a biflavonoid purified from the leaves of Cenostigma pyramidale (Tul.), on modulating the expression of miRs and inflammatory mediators in activated microglia. C20 human microglia were exposed to oligomers of the β-amyloid peptide (Aβ, 500 nM) for 4 h or to lipopolysaccharide (LPS, 1 µg/mL) for 24 h and then treated or not with agathisflavone (1 µM) for 24 h. We observed that β-amyloid and LPS activated microglia to an inflammatory state, with increased expression of miR-146a, miR-155, IL1-β, IL-6, and NOS2. Treatment with agathisflavone resulted in a significant reduction in miR146a and miR-155 induced by LPS or Aβ, as well as inflammatory cytokines IL1-β, IL-6, and NOS2. In cells stimulated with Aβ, there was an increase in p-STAT3 expression that was reduced by agathisflavone treatment. These data identify a role for miRs in the anti-inflammatory effect of agathisflavone on microglia in models of neuroinflammation and AD.

Microwave extraction and molecular imprinted polymer isolation of bergenin applied to the dendrochronological chemical study of Peltophorum dubium

This study describes methodologies for extracting and isolating bergenin, a C-glucoside of 4-O-methylgallic acid found in some plants and it presents various in vitro and in vivo biological activities. Bergenin was previously obtained from the Pelthophorum dubim (Fabaceae) roots with a good yield. Conventional chromatographic procedures of the CHCl3 soluble fraction of the MeOH extract gave 3.62% of this glucoside. An HPLC/DAD method was also developed and validated for bergenin and its precursor, gallic acid quantifications. Microwave extractions with different solvents were tested to optimize the extraction of bergenin, varying the temperature and time. MAE (Microwave Assisted Extraction) was more efficient than conventional extraction procedures, giving a higher yield of bergenin per root mass (0.45% vs. 0.0839%). Molecularly imprinted polymer (MIP) and non-imprinted polymer (NIP) based on bergenin as the template molecule, methacrylic acid, and ethylene glycol dimethacrylate were synthesized and characterized by FTIR and SEM (Scanning Electron Microscopy). Bergenin adsorption experiments using MIP and NIP followed by molecular imprinted solid phase extraction (MISPE) showed that MIP had a higher selectivity for bergenin than NIP. A dendrochronological study using the proposed method for detection and quantification of gallic acid and bergenin in five P. dubium growth rings of a 31-year-old heartwood and in the phelloderm and barks indicated that bergenin was more abundant in the 11-14th growth rings of the heartwood and decreased from the heartwood to the barks.

The Flavonoid Agathisflavone Directs Brain Microglia/Macrophages to a Neuroprotective Anti-Inflammatory and Antioxidant State via Regulation of NLRP3 Inflammasome

Agathisflavone, purified from Cenostigma pyramidale (Tul.) has been shown to be neuroprotective in in vitro models of glutamate-induced excitotoxicity and inflammatory damage. However, the potential role of microglial regulation by agathisflavone in these neuroprotective effects is unclear. Here we investigated the effects of agathisflavone in microglia submitted to inflammatory stimulus in view of elucidating mechanisms of neuroprotection. Microglia isolated from cortices of newborn Wistar rats were exposed to Escherichia coli lipopolysaccharide (LPS, 1 µg/mL) and treated or not with agathisflavone (1 µM). Neuronal PC12 cells were exposed to a conditioned medium from microglia (MCM) treated or not with agathisflavone. We observed that LPS induced microglia to assume an activated inflammatory state (increased CD68, more rounded/amoeboid phenotype). However, most microglia exposed to LPS and agathisflavone, presented an anti-inflammatory profile (increased CD206 and branched-phenotype), associated with the reduction in NO, GSH mRNA for NRLP3 inflammasome, IL1-β, IL-6, IL-18, TNF, CCL5, and CCL2. Molecular docking also showed that agathisflavone bound at the NLRP3 NACTH inhibitory domain. Moreover, in PC12 cell cultures exposed to the MCM previously treated with the flavonoid most cells preserved neurites and increased expression of β-tubulin III. Thus, these data reinforce the anti-inflammatory activity and the neuroprotective effect of agathisflavone, effects associated with the control of NLRP3 inflammasome, standing out it as a promising molecule for the treatment or prevention of neurodegenerative diseases.

Agathisflavone Modifies Microglial Activation State and Myelination in Organotypic Cerebellar Slices Culture

Oligodendrocytes produce the myelin that is critical for rapid neuronal transmission in the central nervous system (CNS). Disruption of myelin has devastating effects on CNS function, as in the demyelinating disease multiple sclerosis (MS). Microglia are the endogenous immune cells of the CNS and play a central role in demyelination and repair. There is a need for new potential therapies that regulate myelination and microglia to promote repair. Agathisflavone (FAB) is a non-toxic flavonoid that is known for its anti-inflammatory and neuroprotective properties. Here, we examined the effects of FAB (5-50 μM) on myelination and microglia in organotypic cerebellar slices prepared from P10-P12 Sox10-EGFP and Plp1-DsRed transgenic mice. Immunofluorescence labeling for myelin basic protein (MBP) and neurofilament (NF) demonstrates that FAB significantly increased the proportion of MBP + /NF + axons but did not affect the overall number of oligodendroglia or axons, or the expression of oligodendroglial proteins CNPase and MBP. FAB is known to be a phytoestrogen, but blockade of α- or β- estrogen receptors (ER) indicated the myelination promoting effects of FAB were not mediated by ER. Examination of microglial responses by Iba1 immunohistochemistry demonstrated that FAB markedly altered microglial morphology, characterized by smaller somata and reduced branching of their processes, consistent with a decreased state of activation, and increased Iba1 protein expression. The results provide evidence that FAB increases the extent of axonal coverage by MBP immunopositive oligodendroglial processes and has a modulatory effect upon microglial cells, which are important therapeutic strategies in multiple neuropathologies.

Determination of anthraquinones in Rhamnus purshiana using HPLC coupled to diode array detector and simple ultraviolet spectroscopic analysis

A new method based on Ultraviolet spectrophotometry was developed and compared with that based on HPLC for the determination and quantification of anthraquinones in the extracts of Rhamnus purshiana bark. A validated quantitative analysis of cascaroside A, cascaroside B, emodin, and aloe-emodin in these herbal products has been previously performed using HPLC coupled with diode array detector. In the HPLC analysis, all the anthraquinones showed satisfactory regression (r² > 0.98) within the test ranges, and the recovery was in the range of 94 to 117%. The limits of detection and quantification ranged from 0.008-0.010 (μg mL^-1 ) and 0.029-0.035 (μg mL^-1 ), respectively. Hierarchical cluster analysis and principal component analysis showed differences in the anthraquinones determined from herbal samples. Subsequently, a simple and low-cost ultraviolet spectrophotometric methodology for the quantitative analysis of the same compounds in the extracts was applied, and all the contents were determined. A paired t-test confirmed that there were no significant differences between the two methods. Our results revealed that the developed method is simple and provides the ability to discriminate and control the quality of anthraquinones in herbal products. This article is protected by copyright. All rights reserved.

New dimer and trimer of chalcone derivatives from anti-inflammatory and antinociceptive extracts of Schinopsis brasiliensis roots

ETHNOPHARMACOLOGY RELEVANCE

Schinopsis brasiliensis Engl. is an endemic tree of the Brazilian semi-arid regions belonging to the Anacardiaceae family. It is the main representative of the genus Schinopsis, mostly native to Brazil and popularly known as "braúna" or "baraúna". Different parts of this plant are employed in Brazilian folk medicines to treat inflammation in general, sexual impotence, cough, and influenza.

AIM OF THE STUDY

This work describes the antinociceptive (acetic acid-induced writhing and formalin-induced nociception) and anti-inflammatory (paw edema and neutrophil migration) activities of the extract of the root of S. brasiliensis. Besides, the evaluation of total phenolic compounds and antioxidant, antimicrobial (including MRSA bacteria), and acetylcholinesterase inhibition activities were also determined.

MATERIAL AND METHODS

The pure compounds were isolated by different chromatographic techniques and their chemical structures have been unambiguously elucidated based on extensive spectroscopic methods, including 1D (¹H, ¹³C, DEPT, and NOEdiff) and 2D (HSQC, HMBC, and NOESY) NMR experiments, MS data, and comparison with the literature data of similar compounds. The antinociceptive and anti-inflammatory activities were evaluated by acid acetic writhing test, formalin paw edema, and by the investigation of neutrophil migration to the peritoneal cavities of mice. For antimicrobial evaluation were determined MIC and MBC, antioxidant activities were obtained by TPC and DPPH tests, and AChE inhibition by Elmann's methodology.

RESULTS

The extracts showed antinociceptive and anti-inflammatory activities and two unusual new compounds, a cyclobutanyl chalcone trimer (schinopsone A) and a cyclohexene-containing chalcone dimer (schinopsone B), with six known compounds were isolated from the active extracts. Additionally, the acetylcholinesterase inhibitory activity for isolated compounds was reported for the first time in this study. Molecular docking studies indicated that the isolated compounds are responsible for the interaction with anti-inflammatory targets (COX 1 and 2 and LOX) with variable binding affinities, indicating a possible mechanism of action of these compounds.

CONCLUSIONS

These findings indicate for the first time the correlation between the anti-inflammatory activity different enriched polyphenol-organic soluble fractions of S. brasiliensis, and it contributes to the understanding of the anti-inflammatory potential of S. brasiliensis.

Potential therapeutic effects of green tea on obese lipid profile - a systematic review

Background: Green tea, obtained from the plant Camellis sinensis, is one of the oldest drinks in the world and contains numerous bioactive compounds. Studies have demonstrated the efficacy of green tea in preventing obesity and cardiovascular diseases that may be related to the reduction of lipid levels. Aim: This study aimed to evidence, through a systematic review, the therapeutic potential of green tea on the lipid profile in preclinical studies in obese animals and clinical studies in obese individuals. Methods: This systematic review follows the recommendations of the preferred report items for systematic reviews and meta-analyses. The electronic databases, PubMed (Medline), Science Direct, Scopus, and Web of Science were consulted. Articles from January 2009 to December 2019 were selected. Results: This search resulted in twenty-nine articles were included cirtically reviewed. In experimental studies, green tea administration has been shown to reduce total cholesterol, triglycerides and low-density lipoprotein cholesterol in animals exposed to obesity-inducing diet. In humans' studies green tea was not shown to be effective for obese lipid control. Because supplementation with green tea extract reduced total cholesterol, triglycerides, low-density lipoprotein for three months at a specific dose. Conclusion: Therefore, green tea appears to act as a protective agent for dyslipidemia in obesity-induced animals. In human studies, green tea has not been shown to be effective in controlling obese lipids.

Evaluation of a commercial loop-mediated isothermal amplification assay, 3MTM Molecular Detection Assay 2 - Campylobacter, for the detection of Campylobacter from poultry matrices

1. The objective of this study was to evaluate performance of a commercial loop-mediated isothermal amplification (LAMP) method as an alternative method for the detection of Campylobacter spp. in primary production samples, poultry rinses and raw poultry products, as compared to the US Department of Agriculture Food Inspection Service Microbiology Laboratory Guide Book PCR reference method, MLG 41A.2. The Campylobacter spp. LAMP was used in conjunction with a ready-to-use enrichment broth that does not require microaerophilic incubation. After enrichment, boot swabs from poultry farms, carcase rinses and raw poultry products were tested by the LAMP method and the MLG 41A PCR method.3. The ready-to-use enrichment broth enabled the growth of Campylobacter spp. within 22 to 28 hours under aerobic incubation conditions. The LAMP method enabled Campylobacter detection in the enriched samples of various poultry matrices and had equivalent sensitivity and specificity to the MLG 41A PCR method.4. No significant difference (95% confidence interval) was found between the alternative and the MLG 41A PCR method, as determined by probability of detection analysis, except for neutralising buffered peptone water post-chill rinsates. For the post-chill neutralising buffered peptone water rinsates, the LAMP method had significantly higher confirmed portions.

The flavonoid agathisflavone modulates the microglial neuroinflammatory response and enhances remyelination

Myelin loss is the hallmark of the demyelinating disease multiple sclerosis (MS) and plays a significant role in multiple neurodegenerative diseases. A common factor in all neuropathologies is the central role of microglia, the intrinsic immune cells of the central nervous system (CNS). Microglia are activated in pathology and can have both pro- and anti-inflammatory functions. Here, we examined the effects of the flavonoid agathisflavone on microglia and remyelination in the cerebellar slice model following lysolecithin induced demyelination. Notably, agathisflavone enhances remyelination and alters microglial activation state, as determined by their morphology and cytokine profile. Furthermore, these effects of agathisflavone on remyelination and microglial activation were inhibited by blockade of estrogen receptor α. Thus, our results identify agathisflavone as a novel compound that may act via ER to regulate microglial activation and enhance remyelination and repair.

The Flavonoid Agathisflavone from Poincianella pyramidalis Prevents Aminochrome Neurotoxicity

Flavonoids have been suggested to protect dopaminergic neurons in Parkinson's disease based on studies that used exogenous neurotoxins. In this study, we tested the protective ability of agathisflavone in SH-SY5Y cells exposed to the endogenous neurotoxin aminochrome. The ability of aminochrome to induce loss of lysosome acidity is an important mechanism of its neurotoxicity. We demonstrated that the flavonoid inhibited cellular death and lysosomal dysfunction induced by aminochrome. In addition, we demonstrated that the protective effect of agathisflavone was suppressed by antagonists of estrogen receptors (ERα and ERβ). These results suggest lysosomal protection and estrogen signaling as mechanisms involved in agathisflavone neuroprotection in a Parkinson's disease study model.

Evaluation of anti-inflammatory, antinociceptive and biological activities of Cenostigma macrophyllum standardized extracts and determination and quantification of the main metabolites

The stem barks and leaves of Cenostigma macrophyllum are used in Brazilian folk medicines in the treatment of stomach and intestinal diseases. However, there are no reports of chromatographic methods used to evaluate the bioactives of its standardized extracts and for biological evaluation. An analytical method was developed and validated for simultaneous determination and quantification of the bioactive phenolics gallic acid, methyl gallate, ellagic acid and, the biflavonoids agathisflavone and amentoflavone in the leaves and stem bark of C. macrophyllum. HPLC operating conditions were optimized and the parameters such as selectivity, linearity, precision, accuracy, LOD, LOQ and, robustness of the method were also evaluated. Robustness was evaluated using a multivariate optimization technique. Linear relationships within the range of investigated concentrations were observed with their correlation coefficients greater than 0.9991. The method was validated for repeatability (RSD ≤ 2.88%), intermediate precision (RSD ≤ 3.38%) with recovery between 84.12 and 106.64% and the RSD less than 3.40% and proved to be robust. Besides, antioxidant, acetylcholinesterase inhibition, anti-inflammatory and antinociceptive activities of the standardized hydromethanolic extracts of leaves and stem bark of this species were evaluated. The method was successfully applied in the quantification of the gallic acid, methyl gallate, ellagic acid, agathisflavone and amentoflavone of standardized extracts. The results showed the present method developed was simple, sensitive, reproducible, accurate and precise. The standardized hydromethanolic extracts of leaves and stem bark of C. macrophyllum showed antioxidant activity (EC₅₀ 69.09 and 83.06 μg mL⁻¹), acetylcholinesterase inhibition (52.23 and 83.36%) and they were able to inhibit the formalin-induced nociception and also reduced the edema formations at 100 mg kg⁻¹ doses. The anti-inflammatory potentials were evaluated by the decrease of the Cg-induced neutrophils migrations at the same doses.

The stem barks and leaves of Cenostigma macrophyllum are used in Brazilian folk medicines in the treatment of stomach and intestinal diseases.

Acetylcholinesterase inhibitory activities and bioguided fractionation of the Ocotea percoriacea extracts: HPLC-DAD-MS/MS characterization and molecular modeling of their alkaloids in the active fraction

In vitro acetylcholinesterase activities of the hexane, dichloromethane, ethyl acetate, n-butanol and aqueous extracts of leaves of Ocotea percoriacea Kosterm. (Lauraceae) were evaluated. The bioguided fractionation of the most active extract (dichloromethane) using silica gel open-column chromatography led to an active alkaloidal fraction composed of isocorydine N-oxide, isocorydine N-oxide derivative, palmatine, roemerine and roemerine N-Oxide. The identification of the chemical structure of these compounds was carried out with high-performance liquid chromatography coupled to electrospray ionization multiple-stage mass spectrometry (HPLC-ESI-MS/MS). Aiming to understand their inhibitory activities, these alkaloids were docked into a 3D model of Electrophorus electricus Acetylcholinesterase (EelAChE) built in the Modeller 9.18 employing homology modeling approach. The results suggest that the alkaloids had the same binding mode and, possibly, the inhibition mechanism of classic drugs (ex. tacrine and donepezil). The structural difference of these compounds opens a new opportunity for the optimization of leading compounds.

Optimization of a technique to quantify the total phenolic compounds in jambolan ( Syzygium cumini Lamark) pulp

Abstract There are various known extraction methods that can be applied to the quantification of phenolic compounds, and thus it is up to the researcher to perfect the process that best applies to the sample in question. Different extraction solvents (liquid-liquid extraction) were compared in order to assess their effectiveness for the analysis of total phenols in jambolan ( Syzygium cumini Lamark) pulp extract using the conventional Folin-Ciocalteau methodology. Three CCRDs (Central Composite Rotational Designs) were carried out to evaluate the factors influencing the extraction process conditions. The variables studied were the solvent concentration (ethanol and methanol, diluted in water) and the mixing time in the compound extraction process. Of the conditions studied, it was shown that a 60% ethanol in water extraction solvent with a mixing time of 10 minutes, in addition to extracting a greater concentration of phenolic compounds, showed the greatest cost benefit advantage, since ethanol is cheaper and less toxic than methanol.

In vitro antioxidant properties of the biflavonoid agathisflavone

Purpose

Free radicals are considered as the causative agents of a variety of acute and chronic pathologies. Natural antioxidants have drawn attention of the researchers in recent years for their ability to scavenge free radicals with minimal or even no side effects. This study evaluates the antioxidant capacity of agathisflavone, a naturally occurring biflavonoid by a number of in vitro methods.

Methods

Agathisflavone was subjected to DPPH, ABTS, OH and NO radical scavenging assay, reducing potential and inhibition of lipid peroxidation (TBARS) test using trolox as a standard.

Results

Agathisflavone showed concentration-dependent antioxidant activity against all types of free radicals used in this study. The antioxidant capacity, reducing potential and inhibition of lipid peroxidation showed by agathisflavone were comparable to that of trolox.

Conclusion

Agathisflavone exhibited antioxidant capacity, which suggests considering this biflavonoid for the use in the prevention and/or treatment of diseases precipitated by oxidative stress.

Agathisflavone, a flavonoid derived from Poincianella pyramidalis (Tul.), enhances neuronal population and protects against glutamate excitotoxicity

Flavonoids are bioactive compounds that are known to be neuroprotective against glutamate-mediated excitotoxicity, one of the major causes of neurodegeneration. The mechanisms underlying these effects are unresolved, but recent evidence indicates flavonoids may modulate estrogen signaling, which can delay the onset and ameliorate the severity of neurodegenerative disorders. Furthermore, the roles played by glial cells in the neuroprotective effects of flavonoids are poorly understood. The aim of this study was to investigate the effects of the flavonoid agathisflavone (FAB) in primary neuron-glial co-cultures from postnatal rat cerebral cortex. Compared to controls, treatment with FAB significantly increased the number of neuronal progenitors and mature neurons, without increasing astrocytes or microglia. These pro-neuronal effects of FAB were suppressed by antagonists of estrogen receptors (ERα and ERβ). In addition, treatment with FAB significantly reduced cell death induced by glutamate and this was associated with reduced expression levels of pro-inflammatory (M1) microglial cytokines, including TNFα, IL1β and IL6, which are associated with neurotoxicity, and increased expression of IL10 and Arginase 1, which are associated with anti-inflammatory (M2) neuroprotective microglia. We also observed that FAB increased neuroprotective trophic factors, such as BDNF, NGF, NT4 and GDNF. The neuroprotective effects of FAB were also associated with increased expression of glutamate regulatory proteins in astrocytes, namely glutamine synthetase (GS) and Excitatory Amino Acid Transporter 1 (EAAT1). These findings indicate that FAB acting via estrogen signaling stimulates production of neurons in vitro and enhances the neuroprotective properties of microglia and astrocytes to significantly ameliorate glutamate-mediated neurotoxicity.

Seasonal variation in the chemical composition of two chemotypes of Lippia alba

Lippia alba is a popular Brazilian herb known as 'cidreira' that presents several chemotypes which exhibit different chemical profile and they are widely used as seasonings and traditional medicine. This work describes the seasonal variation of metabolites of polar extracts of carvone and linalool chemotypes, identified by GC-MS analyses of the essential oils. A methodology was elaborated in order to obtain a seasonal variation in the chemical composition of leaf employing HPLC-DAD. Acteoside, isoacteoside, geneposidic acid, 8-epi-loganin, mussaenoside, luteolin 7-O-glucoside, apigenin 7-O-glucuronide and tricin 7-O-diglucuronide have been isolated and identified for validation procedures and chromatographic analysis. Geneposidic acid was presented in all samples, in contrast to the 8-epi-loganin and, mussaenoside which were presented only in the carvone-chemotype. Acteoside was the major metabolite detected from July to November while tricin-7-O-diglucuronide was the major compound in all other months. Besides, phenylpropanoids are predominant in winter and flavonoids in summer season.

Betulinic Acid from Zizyphus Joazeiro Bark Using Focused Microwave-Assisted Extraction and Response Surface Methodology

BACKGROUND

The effect of the extraction time (min) and temperature (°C) on the yield of betulinic acid (BA) from Zizyphus joazeiro barks using focused microwave-assisted extraction was investigated.

MATERIALS AND METHODS

The ethyl acetate was used as extractor solvent because it was shown to provide a betulinic acid-clean extract. A full two-level statistical factorial design was applied to determine the important effects and interactions of these independent variables upon the yield of BA.

RESULTS

The conditions that produced the highest yield of BA were at temperature of 70°C and an extraction time of 15 min (3.33 mg per gram of plant).

CONCLUSION

The BA has drawn attention due to its use as a raw material in the synthesis of active compounds against the Human Immunodeficiency Virus (HIV).

SUMMARY

The extraction of betulinic acid (BA) from Zizyphus joazeiro barks using focused microwave was investigatedA full two-level statistical factorial design was applied to determine the effects and interactions of the independent variables (time and temperature) upon the yield of BAThe reversed-phase high-performance liquid chromatography with diode-array detector was used for quantification. Abbreviation used: BA: Betulinic acid; FMAE: Focused microwave assisted extraction; HPLC: High-performance liquid chromatography; RSD: Relative standard deviations.

Cytotoxicity of the diterpene 14-O-methyl-ryanodanol from Erythroxylum passerinum in an astrocytic cells model

Plant secondary metabolites, such as, specifically, alkaloids and terpenes, may present psychoactive properties that modify the function of the central nervous system (CNS) and induce neurotoxicity. Neurotoxicity involves the response of glial cells, mainly astrocytes, which play a fundamental role in the control of homeostasis of the CNS. Some Erythroxylum species are indigenous to the state of Bahia in Brazil. This study investigated the cytotoxic activity of the diterpene AEP-1, extracted from the fruit of E. passerinum in a GL-15 cell line, astrocytic, glial cells model. The effects on cell viability, analyzed by the MTT assay, demonstrated a dose-dependent cytotoxic effect, with maximum effect at 500 μg/mL of AEP-1, and with a reduction of about 40 and 47% on cellular viability after 24 h and 72 h treatment, respectively. Evidence for induction of apoptosis by AEP-1 was first obtained when GL-15 glial cells were incubated with 250 μg/mL AEP-1 causing reniform and/or pyknotic nuclei and apoptotic bodies revealed by chromatin staining with Hoechst 33258. Increase in DNA fragmentation was also observed by comet assays in cells incubated with 500 μg/mL of AEP-1. Moreover, cells exposed to a sub toxic dose of AEP-1 (250 μg/mL) showed significant changes in morphology--contraction of the cytoplasm and expansion of cellular projections--signifying the presence of astrocytic cytoskeletal protein and glial fibrillary acidic protein (GFAP). These findings indicated astrocytic cells as the target for terpene AEP-1 and suggest the involvement of glial cells with psychoactive symptoms observed in humans and animals after consumption of fruits of plants of the genus Erythroxylum.

The Bayesian microbial subtyping attribution model: robustness to prior information and a proposition

Attributing foodborne illnesses to food sources is essential to conceive, prioritize, and assess the impact of public health policy measures. The Bayesian microbial subtyping attribution model by Hald et al. is one of the most advanced approaches to attribute sporadic cases; it namely allows taking into account the level of exposure to the sources and the differences between bacterial types and between sources. This step forward requires introducing type and source-dependent parameters, and generates overparameterization, which was addressed in Hald's paper by setting some parameters to constant values. We question the impact of the choices made for the parameterization (parameters set and values used) on model robustness and propose an alternative parameterization for the Hald model. We illustrate this analysis with the 2005 French data set of non-typhi Salmonella. Mullner's modified Hald model and a simple deterministic model were used to compare the results and assess the accuracy of the estimates. Setting the parameters for bacterial types specific to a unique source instead of the most frequent one and using data-based values instead of arbitrary values enhanced the convergence and adequacy of the estimates and led to attribution estimates consistent with the other models' results. The type and source parameters estimates were also coherent with Mullner's model estimates. The model appeared to be highly sensitive to parameterization. The proposed solution based on specific types and data-based values improved the robustness of estimates and enabled the use of this highly valuable tool successfully with the French data set.

Attribution of the French human Salmonellosis cases to the main food-sources according to the type of surveillance data

Salmonella are the most common bacterial cause of foodborne infections in France and ubiquitous pathogens present in many animal productions. Assessing the relative contribution of the different food-animal sources to the burden of human cases is a key step towards the conception, prioritization and assessment of efficient control policy measures. For this purpose, we considered a Bayesian microbial subtyping attribution approach based on a previous published model (Hald et al., 2004). It requires quality integrated data on human cases and on the contamination of their food sources, per serotype and microbial subtype, which were retrieved from the French integrated surveillance system for Salmonella. The quality of the data available for such an approach is an issue for many countries in which the surveillance system has not been designed for this purpose. In France, the sources are monitored simultaneously by an active, regulation-based surveillance system that produces representative prevalence data (as ideally required for the approach) and a passive system relying on voluntary laboratories that produces data not meeting the standards set by Hald et al. (2004) but covering a broader range of sources. These data allowed us to study the impact of data quality on the attribution results, globally and focusing on specific features of the data (number of sources and contamination indicator). The microbial subtyping attribution model was run using an adapted parameterization previously proposed (David et al., 2012). A total of 9076 domestic sporadic cases were included in the analyses as well as 9 sources among which 5 were common to the active and the passive datasets. The greatest impact on the attribution results was observed for the number of sources. Thus, especially in the absence of data on imported products, the attribution estimates presented here should be considered with caution. The results were comparable for both types of surveillance, leading to the conclusion that passive data constitute a potential cost-effective complement to active data collection, especially interesting because the former encompass a greater number of sources. The model appeared robust to the type of surveillance, and provided that some methodological aspects of the model can be enhanced, it could also serve as a risk-based guidance tool for active surveillance systems.

Box-Behnken design: An alternative for the optimization of analytical methods

The present paper describes fundamentals, advantages and limitations of the Box-Behnken design (BBD) for the optimization of analytical methods. It establishes also a comparison between this design and composite central, three-level full factorial and Doehlert designs. A detailed study on factors and responses involved during the optimization of analytical systems is also presented. Functions developed for calculation of multiple responses are discussed, including the desirability function, which was proposed by Derringer and Suich in 1980. Concept and evaluation of robustness of analytical methods are also discussed. Finally, descriptions of applications of this technique for optimization of analytical methods are presented.

Statistical designs and response surface techniques for the optimization of chromatographic systems

This paper describes fundamentals and applications of multivariate statistical techniques for the optimization of chromatographic systems. The surface response methodologies: central composite design, Doehlert matrix and Box-Behnken design are discussed and applications of these techniques for optimization of sample preparation steps (extractions) and determination of experimental conditions for chromatographic separations are presented. The use of mixture design for optimization of mobile phases is also related. An optimization example involving a real separation process is exhaustively described. A discussion about model validation is presented. Some applications of other multivariate techniques for optimization of chromatographic methods are also summarized.

Oleanolic Acid, a pentacyclic triterpene attenuates the mustard oil-induced colonic nociception in mice

Many natural terpenoid compounds from plants exhibit antinociceptive property but very few studies have addressed their efficacy in visceral models of nociception. The present study evaluated the antinociceptive potential of oleanolic acid, a pentacyclic triterpene in the mouse model of colonic nociception induced by mustard oil. We further examined the possible participation of opioid, alpha2-adrenergic, and transient receptor potential vanilloid 1 (TRPV1)-receptors in its mechanism. Mice were pretreated orally with oleanolic acid (3, 10, 30 mg/kg) or vehicle, and the pain-related behavioral responses to intracolonic injection of mustard oil was analysed. Oleanolic acid significantly suppressed the mustard oil-induced nociceptive behaviors at test doses of 10 and 30 mg/kg, in a dose-related manner. The antinociceptive effect of oleanolic acid (30 mg/kg) was significantly blocked by pretreatment with the opioid antagonist, naloxone (2 mg/kg, i.p.), while the alpha2-adrenoceptor antagonist, yohimbine (2 mg/kg, s.c.), had no effect. Pretreatment with ruthenium red (3 mg/kg, s.c.), a non-competitive TRPV1 antagonist alone caused significant inhibition of mustard oil-induced nociception but its co-administration with oleanolic acid produced neither antagonism nor potentiation of oleanolic acid antinociception. In the open-field test that detects sedative or motor abnormality, mice received 30 mg/kg oleanolic acid did not show any per se influence, but significantly inhibited the mustard oil-induced decrease in ambulation frequency. These data demonstrate the visceral antinociceptive potential of oleanolic acid that involves an opioid mechanism and possibly a modulatory influence on vanilloid-receptors, which needs further study.

[Doping in sports. Cases reported to the Poison Control Center of Marseille from 1992 to 2000]

OBJECTIVE

To study the doping substances used in sport and their toxicity.

METHODS

Retrospective analysis from January 1992 to December 2000 of the cases of use of doping substances in sport reported by telephone to the anti-poison center in Marseilles.

RESULTS

Fifty-one cases were reported concerning 48 men and 3 women with a mean age of 30, ranging from 10 to 55 years. Sixty-three percent of cases were reported over the last four years. The sport practiced was bodybuilding, except in 2 cases (cycling in one case and running in the other). The products used were mainly anabolizing hormones (15 times), clenbuterol (14 times) and creatine (7 times). A third of cases concerned associations of substances and 19 cases presented with symptomatology.

CONCLUSION

The diversity in nature and status of the substances mentioned and their association requires enhanced vigilance with regard to the use of drugs in sport. The recent measures voted within the framework of the anti-doping law dated 23/3/99 are aimed at increasing surveillance with the development of anti-doping antennae.

Biflavonoids from Ouratea multiflora

A new flavone dimer, 3-hydroxy-4',5,7-trimethoxyflavone-(6-->8")-3"-hydroxy-3"',4"', 5",7"-tetramethoxyflavone, together with amenthoflavone, have been isolated from the leaves of Ouratea multiflora. Its structure was established by spectroscopic methods, including two-dimensional NMR spectroscopy.

Alkyl phenols and derivatives from Tapirira obtusa

From the bark of Tapiria obtusa, six alkyl phenol derivatives were isolated: 1-hydroxy-3-[(Z)-7'-nonadecenyl]-benzene, 1-hydroxy-3-[(Z)-7'-heptadecenyl]-benzene, 1-hydroxy-3-[14'-phenyltetradecyl]-benzene, and 1-hydroxy-3-[16'-phenyltetradecyl]-benzene, and their possible biogenetic precursors, 1-(16'-phenyl-12'Z-hexadecenyl)-4-Z-cyclohexene-(1S*,3S*)-diol and (4S*,6S*)-dihydroxy-6-(14'Z-nonadecenyl)-2-cyclohexenone. The structures of these compounds were elucidated by chemical and spectroscopic analysis, (4S*,6S*)-Dihydroxy-6-(14'Z-nonadecenyl)-2-cyclohexenone showed cytotoxic activity.

A-type proanthocyanidin antioxidant from Dioclea lasiophylla

The A-type proanthocyanidin, epigallocatechin-(2beta-->7,4beta-->8)-epicatechin, together with the known epicatechin, luteolin 3'beta-D-glucopyranoside, chrysoeriol 7beta-D-glucopyranoside and 2-methylpentan-2,4-diol, were isolated from leaves of Dioclea lasiophilla. The structures were established on the basis of their spectral data. Antioxidant activities of isolates were measured using the autooxidation of beta-carotene in a linolenic acid suspension method.

[Accidental narcotic and buprenorphine poisoning in children notified at the Marseille Poison Center between 1993 and 1999]

To evaluate the frequency and severity of accidental poisoning in children by narcotics or buprenorphine, a retrospective study was carried out: 75 cases were collected by the Marseille Poison Centre between 1993 and 1999. Most of the patients were between 1 and 3 years old and the drugs involved were cannabis and, more recently, Subutex (buprenorphine). These two drugs were responsible for the most severe cases of poisoning, most of which occurred at home.

Constituents of Caesalpinia pyramidalis

Two new glycosyl phenylpropenoid acids, 4-O-beta-glucopyranosyloxy-(Z)-7-hydroxycinnamic acid (1) and 4-O-beta-glucopyranosyloxy-(Z)-8-hydroxycinnamic acid (2), besides lupeol and aghatisflavone, were isolated from the leaves of Caesalpinia pyramidalis.

[Evaluation of intravenous immunotherapy with purified F(ab')2 fragments (Viperfav)]

OBJECTIVES

To assess early clinical and biological prognosis factors in viper envenomings, and assess efficacy of Viperfav immunotherapy. Viperfav contains purified F(ab')2 fragments of equine antibodies.

PATIENTS AND METHODS

A retrospective case review study of viper envenomings collected by two poison centers in France, treated or not treated by Viperfav, was conducted. Two hundred seven cases of viper bites including 119 moderate or severe envenomings (Grade II and III, recorded in adults and children and collected from 1992 to 1997 were included. Before treatment, clinical gradation and early biological severity criteria were collected. After treatment, or grade II and III envenomings, the two treatment groups were compared concerning severity and frequency of complications and sequelae, duration of hospitalization in intensive care unit (ICU) and duration of total hospital stay.

RESULTS

Before treatment, both groups were not significantly different. In the Viperfav treatment group, there was a significantly lower incidence of complications (4% vs. 21%, p = 0.02) and sequelae (0% vs 14%, p = 0.006). ICU stay greater than 3 days occurred in 28% of patients in the symptomatic treatment group and no case was recorded in the Viperfav group (p = 0.0002). Total hospital stay was reduced significantly in the Viperfav group versus symptomatic treatment group (3.3 vs. 8.7 days, p = 0.000002).

CONCLUSIONS

Viperfav immunotherapy was safe and effective for rapidly counteracting venom toxicity and improved markedly the prognosis of viper envenomations. The studied clinical and biological prognosis factors are valuable tools for predicting moderate or severe envenomings and are helpful for early prescription of Viperfav antivenom.

[Methamidophos intoxication: immediate and late neurological toxicity; two case reports]

Méthamidophos is an organophosphorus insecticide which delayed neurotoxicity is more frequent than with other organophosphates. Authors present a case report concerning a collective poisoning after cutaneous contact: two farm labourers presented moderate cholinergic signs quickly followed by proximal neurological signs (retrobulbar ocular neuritis for one patient, thight paresthesias for the second one). These signs decreased meanwhile new neurological symptoms appeared: sensory and motor peripheral neuropathy in both patients, with a clinical aspect of OrganoPhosphorus Induced Delayed Neuropathy (OPIDN). This unusual chronology and the disappearence of all signs at the 18th month, lead the authors to diagnose a collective methamidophos poisoning in three phases: first, anticholinesterasic acute syndrome; second, an intermediate syndrome and third an OPIDN.

[Acute renal insufficiency caused by Amanita proxima poisoning: experience of the Poison Center of Marseille]

In southern France, some Amanita species are usually eaten like Amanita ovoidea (Quélet, 1872) which is a common white mushroom. In same areas, a similar and less common fungus can be encountered: Amanita proxima (Dumee, 1916). The first published cases of Amanita proxima poisonings with acute renal failure have been reported in 1994 by a medical team from Montpellier. A second article was published in 1995 by physicians from Marseille. In order to evaluate the importance of the confusion between the 2 species, we looked after these mushroom poisonings collected by the Poison Centre of Marseille. We found 31 cases concerning 53 patients. We observed the first intoxication in 1968. Poisonings took place in the south of Provence. Ingestions are in 26 cases (83% of the 31 cases) due to the confusion with Amanita ovoidea. The average delay between the meal and the first signs was 13 hours and 12 minutes. All patients had gastro-intestinal symptoms, and for 14 of them, oliguria or anuria appeared in a few days after ingestion. 11 patients needed temporary dialysis, and for 10 of them, moderate hepatic cytolysis was observed. The severity of symptoms seems to be dose-dependent: we collected cases in the same family with no signs after just tasting the meal, digestive symptoms only when patients at more, and renal failure for the hungry people.