Biosafety assessment of probiotics used for human consumption: recommendations from the EU-PROSAFE project

On June 26-27, 2006, 60 academic and industry scientists gathered during the PROSAFE workshop to discuss recommendations on taxonomy, antibiotic resistance, in vitro assessment of virulence and in vivo assessment of safety of probiotics used for human consumption. For identification of lactic acid bacteria (LAB) intended for probiotic use, it was recommended that conventional biochemical methods should be complemented with molecular methods and that these should be performed by an expert lab. Using the newly developed LAB Susceptibility test Medium (LSM), tentative epidemiological cut-off values were proposed. It was recommended that potentially probiotic strains not belonging to the wildtype distributions of relevant antimicrobials should not be developed as future products for human or animal consumption. Furthermore, it was recommended that the use of strains harbouring known and confirmed virulence genes should be avoided. Finally, for in vivo assessment of safety by investigating strain pathogenicity in animal models, the rat endocarditis model appeared to be the most reliable model tested in the PROSAFE project. Moreover, consensus was reached for approving the necessity of a human colonisation study in a randomised placebo-controlled double-blind design; however, further discussions are needed on the details of such as study.

Using transcription modules to identify expression clusters perturbed in Williams-Beuren syndrome.

The genetic dissection of the phenotypes associated with Williams-Beuren Syndrome (WBS) is advancing thanks to the study of individuals carrying typical or atypical structural rearrangements, as well as in vitro and animal studies. However, little is known about the global dysregulations caused by the WBS deletion. We profiled the transcriptomes of skin fibroblasts from WBS patients and compared them to matched controls. We identified 868 differentially expressed genes that were significantly enriched in extracellular matrix genes, major histocompatibility complex (MHC) genes, as well as genes in which the products localize to the postsynaptic membrane. We then used public expression datasets from human fibroblasts to establish transcription modules, sets of genes coexpressed in this cell type. We identified those sets in which the average gene expression was altered in WBS samples. Dysregulated modules are often interconnected and share multiple common genes, suggesting that intricate regulatory networks connected by a few central genes are disturbed in WBS. This modular approach increases the power to identify pathways dysregulated in WBS patients, thus providing a testable set of additional candidates for genes and their interactions that modulate the WBS phenotypes.

Excitotoxicity-induced endocytosis confers drug targeting in cerebral ischemia.

OBJECTIVE: Targeting neuroprotectants specifically to the cells that need them is a major goal in biomedical research. Many peptidic protectants contain an active sequence linked to a carrier such as the transactivator of transcription (TAT) transduction sequence, and here we test the hypothesis that TAT-linked peptides are selectively endocytosed into neurons stressed by excitotoxicity and focal cerebral ischemia. METHODS: In vivo experiments involved intracerebroventricular injection of TAT peptides or conventional tracers (peroxidase, fluorescein isothiocyanate-dextran) in young rats exposed to occlusion of the middle cerebral artery at postnatal day 12. Cellular mechanisms of uptake were analyzed in dissociated cortical neuronal cultures. RESULTS: In both models, all tracers were taken up selectively into stressed neurons by endocytosis. In the in vivo model, this was neuron specific and limited to the ischemic area, where the neurons displayed enhanced immunolabeling for early endosomal antigen-1 and clathrin. The highly efficient uptake of TAT peptides occurred by the same selective mechanism as for conventional tracers. All tracers were targeted to the nucleus and cytoplasm of neurons that appeared viable, although ultimately destined to die. In dissociated cortical neuronal cultures, an excitotoxic dose of N-methyl-D-aspartate induced a similar endocytosis. It was 100 times more efficient with TAT peptides than with dextran, because the former bound to heparan sulfate proteoglycans at the cell surface, but it depended on dynamin and clathrin in both cases. INTERPRETATION: Excitotoxicity-induced endocytosis is the main entry route for protective TAT peptides and targets selectively the neurons that need to be protected.

Foods, nutrients and the risk of oral and pharyngeal cancer.

Background:Besides tobacco and alcohol, dietary habits may have a relevant role in oral cavity and pharyngeal (OCP) cancer.Methods:We analysed the role of selected food groups and nutrients on OCP cancer in a case-control study carried out between 1997 and 2009 in Italy and Switzerland. This included 768 incident, histologically confirmed squamous cell carcinoma cases and 2078 hospital controls. Odds ratios (ORs) were estimated using logistic regression models including terms for tobacco, alcohol and other relevant covariates.Results:Significant inverse trends in risk were observed for all vegetables (OR=0.19, for the highest vs the lowest consumption) and all fruits (OR=0.39), whereas significant direct associations were found for milk and dairy products (OR=1.50), eggs (OR=1.71), red meat (OR=1.55), potatoes (OR=1.85) and desserts (OR=1.68), although trends in risk were significant only for potatoes and desserts. With reference to nutrients, significant inverse relations were observed for vegetable protein (OR=0.45, for the highest vs the lowest quintile), vegetable fat (OR=0.54), polyunsaturated fatty acids (OR=0.53), α-carotene (OR=0.51), β-carotene (OR=0.28), β-cryptoxanthin (OR=0.37), lutein and zeazanthin (OR=0.34), vitamin E (OR=0.26), vitamin C (OR=0.40) and total folate (OR=0.34), whereas direct ones were observed for animal protein (OR=1.57), animal fat (OR=2.47), saturated fatty acids (OR=2.18), cholesterol (OR=2.29) and retinol (OR=1.88). Combinations of low consumption of fruits and vegetables, and high consumption of meat with high tobacco and alcohol, led to 10- to over 20-fold excess risk of OCP cancer.Conclusion:Our study confirms and further quantifies that a diet rich in fruits and vegetables and poor in meat and products of animal origin has a favourable role against OCP cancer.

Planning sleep-related animal and translational research

With the aim of improving human health, scientists have been using an approach referred to as translational research, in which they aim to convey their laboratory discoveries into clinical applications to help prevent and cure disease. Such discoveries often arise from cellular, molecular, and physiological studies that progress to the clinical level. Most of the translational work is done using animal models that share common genes, molecular pathways, or phenotypes with humans. In this article, we discuss how translational work is carried out in various animal models and illustrate its relevance for human sleep research and sleep-related disorders.

Is our heart a well-designed pump? The heart along animal evolution.

A carrier system for gases and nutrients became mandatory when primitive animals grew larger and developed different organs. The first circulatory systems are peristaltic tubes pushing slowly the haemolymph into an open vascular tree without capillaries (worms). Arthropods developed contractile bulges on the abdominal aorta assisted by accessory hearts for wings or legs and by abdominal respiratory motions. Two-chamber heart (atrium and ventricle) appeared among mollusks. Vertebrates have a multi-chamber heart and a closed circulation with capillaries. Their heart has two chambers in fishes, three chambers (two atria and one ventricle) in amphibians and reptiles, and four chambers in birds and mammals. The ventricle of reptiles is partially divided in two cavities by an interventricular septum, leaving only a communication of variable size leading to a variable shunt. Blood pressure increases progressively from 15 mmHg (worms) to 170/70 mmHg (birds) according to the increase in metabolic rate. When systemic pressure exceeds 50 mmHg, a lower pressure system appears for the circulation through gills or lungs in order to improve gas exchange. A four-chamber heart allows a complete separation of systemic and pulmonary circuits. This review describes the circulatory pumping systems used in the different classes of animals, their advantages and failures, and the way they have been modified with evolution.

Role of dendritic cells in the lung: in vitro models, animal models and human studies

Dendritic cells (DCs) are the most potent antigen-presenting cells in the human lung and are now recognized as crucial initiators of immune responses in general. They are arranged as sentinels in a dense surveillance network inside and below the epithelium of the airways and alveoli, where thet are ideally situated to sample inhaled antigen. DCs are known to play a pivotal role in maintaining the balance between tolerance and active immune response in the respiratory system. It is no surprise that the lungs became a main focus of DC-related investigations as this organ provides a large interface for interactions of inhaled antigens with the human body. During recent years there has been a constantly growing body of lung DC-related publications that draw their data from in vitro models, animal models and human studies. This review focuses on the biology and functions of different DC populations in the lung and highlights the advantages and drawbacks of different models with which to study the role of lung DCs. Furthermore, we present a number of up-to-date visualization techniques to characterize DC-related cell interactions in vitro and/or in vivo.

Besoins, prescriptions et sécurité des produits sanguins labiles ; autosuffisance en produits sanguins labiles [Roundtables of SFTS Congress 2013: Needs, indications and safety of blood products; self-sufficiency in blood products].

The current issues debate brings together experts around the themes of self-sufficiency (in its national and European aspects) and of needs in cellular blood products. The point of view of the manufacturer and prescribers of blood products are confronted.

A new drug delivery system inhibits uveitis in an animal model after cataract surgery.

Cataract surgery is a common ocular surgical procedure consisting in the implantation of an artificial intraocular lens (IOL) to replace the ageing, dystrophic or damaged natural one. The management of postoperative ocular inflammation is a major challenge especially in the context of pre-existing uveitis. The association of the implanted IOL with a drug delivery system (DDS) allows the prolonged intraocular release of anti-inflammatory agents after surgery. Thus IOL-DDS represents an "all in one" strategy that simultaneously addresses both cataract and inflammation issues. Polymeric DDS loaded with two model anti-inflammatory drugs (triamcinolone acetonide (TA) and cyclosporine A (CsA)) were manufactured in a novel way and tested regarding their efficiency for the management of intraocular inflammation during the 3 months following surgery. The study involved an experimentally induced uveitis in rabbits. Experimental results showed that medicated DDS efficiently reduced ocular inflammation (decrease of protein concentration in aqueous humour, inflammatory cells in aqueous humour and clinical score). Additionally, more than 60% of the loading dose remained in the DDS at the end of the experiment, suggesting that the system could potentially cover longer inflammatory episodes. Thus, IOL-DDS were demonstrated to inhibit intraocular inflammation for at least 3 months after cataract surgery, representing a potential novel approach to cataract surgery in eyes with pre-existing uveitis.

The fallacy of slimming products: a case analysis in Switzerland

Introduction: Many people desire to lose weight. This favors the marketing of "miracle" products with overemphasized slimming capacities. To our knowledge, no study regarding the claimed performances of slimming products has ever been conducted in Switzerland. Objectives: To assess weight loss claims of slimming products available in Switzerland by analyzing their corresponding advertisements. Methods: Between May 2008 and February 2013, 31 advertisements for 13 different slimming products from a single producer were collected. Weight loss claims and text of the advertisement were analyzed. Results: Weight loss claims ranged between 7 and 31 kg, with an estimated daily weight loss ranging between 300 g and 1 kg. 84% of the advertisements targeted women (by including the photograph of a woman), 61% showed a picture of a person before and after using the product, and 51% claimed that the product had improved marital relationships. The terms "natural", "miracle/extraordinary" and "scientific" were present in 92%, 77%, and 31% of the products, respectively. Free gifts were provided to buyers for 69% of the products. Cost was very similar for all 13 products (range: 49 to 59 CHF, with 8 products costing the same amount) and no correlation was found between cost of the product and weight loss claims. No differences were found for weight loss claims according to presence or absence of a picture or of the terms ".natural", ".miracle/extraordinary" and ".scientific" Finally, the yearly costs for advertising such products (French-speaking Switzerland) ranged between 56,000 and 126,000 CHF, suggesting that the gains obtained were higher than this value. Conclusion: In Switzerland, advertisements for slimming products use positive and reassuring terms to attract consumers, which are lured by unreachable, false promises of rapid and easy weight loss. Taking into account the costs of advertising, the gains obtained appear to be significant. Legislation on advertising of such products is urgently needed.