Safe and efficacious probiotics: what are they?

Each year, >20 billion doses of probiotics are used by healthy people and by those diagnosed with a range of medical conditions. Compared to many pharmaceutical agents, probiotics are well tolerated and extremely safe, and serious adverse effects rarely occur. Nevertheless, as many new researchers enter the field and companies launch "probiotic" products, it is essential that standards are set for naming a product "probiotic" to show that it meets an acceptable level of safety and efficacy, and to understand the strengths and limitations of its activity. In this Opinion article, recommendations are made based upon the current understanding of scientific, clinical and regulatory issues, with a special focus on safety.     

Late-onset porphyrias: what are they?

Porphyrias are inherited disorders of heme biosynthesis. ALA dehydratase porphyria (ADP) and congenital erythropoietic porphyria (CEP) are autosomal recessive porphyrias, and are typically expressed at birth or in childhood. However, a few cases of late-onset recessive porphyrias have been reported. Recently we encountered a late-onset ADP patient who developed symptoms of acute porphyria when he was 63 years old. This was accompanied by polycythemia vera. It was concluded that he developed the porphyria because an abnormal ALAD allele was clonally expanded by polycythemia vera. Upon reviewing the literature, a few cases of late-onset CEP were found to be also associated with hematologic abnormalities suggestive of myelodysplastic syndrome (MDS), another clonal disorder. These findings suggest that these late-onset porphyrias may be heterozygous for their gene defects, but clinical expression may be elicited if there is a loss of heterozygosity, either by a clonal expansion of the porphyric allele or by a loss of function mutation in the other allele.     

Ciliary subcompartments: how are they established and what are their functions?

Cilia are conserved subcellular organelles with diverse sensory and developmental roles. Recently, they have emerged as crucial organelles whose dysfunction causes a wide spectrum of disorders called ciliopathies. Recent studies on the pathological mechanisms underlying ciliopathies showed that the ciliary compartment is further divided into subdomains with specific roles in the biogenesis, maintenance and function of cilia. Several conserved sets of molecules that play specific roles in each subcompartment have been discovered. Here we review recent progress on our understanding of ciliary subcompartments, especially focusing on the molecules required for their structure and/or function. [BMB Reports 2015; 48(7): 380-387]     

Antibiotic use in animal agriculture: what have we learned and where are we going?

Antibiotics are enormously important for the humane and efficient production of food animals. These benefits are somewhat offset by the human and animal health antibiotic resistance risks posed by their use in animals. This article provides an overview of what we have learned about antibiotic resistance as an issue in animal agriculture and where that knowledge could lead us in the future. To preserve the effectiveness of antibiotics, more action is needed to ensure their prudent use, particularly in the case of antibiotic growth promoters and antibiotics deemed critically important for human and animal health.     

Radiation-induced bystander effects: what are they, and how relevant are they to human radiation exposures?

The term radiation-induced bystander effect is used to describe radiation-induced biological changes that manifest in unirradiated cells remaining within an irradiated cell population. Despite their failure to fit into the framework of classical radiobiology, radiation-induced bystander effects have entered the mainstream and have become established in the radiobiology vocabulary as a bona fide radiation response. However, there is still no consensus on a precise definition of radiation-induced bystander effects, which currently encompasses a number of distinct signal-mediated effects. These effects are classified here into three classes: bystander effects, abscopal effects and cohort effects. In this review, the data have been evaluated to define, where possible, various features specific to radiation-induced bystander effects, including their timing, range, potency and dependence on dose, dose rate, radiation quality and cell type. The weight of evidence supporting these defining features is discussed in the context of bystander experimental systems that closely replicate realistic human exposure scenarios. Whether the manifestation of bystander effects in vivo is intrinsically limited to particular radiation exposure scenarios is considered. The conditions under which radiation-induced bystander effects are induced in vivo will ultimately determine their impact on radiation-induced carcinogenic risk.     

Disturbance–diversity models: what do they really predict and how are they tested?

The intermediate disturbance hypothesis (IDH) and the dynamic equilibrium model (DEM) are influential theories in ecology. The IDH predicts large species numbers at intermediate levels of disturbance and the DEM predicts that the effect of disturbance depends on the level of productivity. However, various indices of diversity are considered more commonly than the predicted number of species in tests of the hypotheses. This issue reaches beyond the scientific community as the predictions of the IDH and the DEM are used in the management of national parks and reserves. In order to compare responses with disturbance among measures of biodiversity, we used two different approaches of mathematical modelling and conducted an extensive meta-analysis. Two-thirds of the surveyed studies present different results for different diversity measures. Accordingly, the meta-analysis showed a narrow range of negative quadratic regression components for richness, but not evenness. Also, the two models support the IDH and the DEM, respectively, when biodiversity is measured as species richness, but predict evenness to increase with increasing disturbance, for all levels of productivity. Consequently, studies that use compound indices of diversity should present logical arguments, a priori, to why a specific index of diversity should peak in response to disturbance.     

Comparing plant and animal extracellular matrix-cytoskeleton connections — are they alike?

Summary Cell adhesion and communication is one of the most fascinating fields of modern biology. How do cells receive information from the environment and from neighboring cells? How does this information elicit morphogenesis, cell division and migration? The recent identification of the surface molecules involved in these events in animal systems is beginning to disclose that a continuum, extracellular matrix-plasma membrane-cytoskeleton, may be a common structure present in all eukaryotic cells. In this article we compare current knowledge on this complex structure in animal systems to the emerging data on plants. We point out the areas that need additional research to fully understand the role of the cell wall-cytoskeleton continuum in plants.Abbreviations ABP actin-binding protein - AGP arabinogalactan proteins - CTK cytoskeleton - ECM extracellular matrix - FN fibronectin - hFN human fibronectin - HRGP hydroxyproline-rich glycoproteins - hVN human vitronectin - PM plasma membrane - SAM substrate adhesion molecule - VN vitronectin Dedicated to Professor Dr. Hartmut K. Lichtenthaler on the occasion of his 60th birthday     

Q&A: what are brassinosteroids and how do they act in plants?

Brassinosteroids (BRs) are a class of polyhydroxylated steroidal phytohormones in plants with similar structures to animals’ steroid hormones. Brassinosteroids regulate a wide range of physiological processes including plant growth, development and immunity. Brassinosteroid signalling and its integration with other signalling pathways have been investigated thoroughly at the molecular level.     

What are artificial neural networks and what they can do?

The artificial neural networks (ANN) are very often applied in many areas of toxicology for the solving of complex problems, such as the prediction of chemical compound properties and quantitative structure-activity relationship. The aim of this contribution is to give the basic knowledge about conception of ANN, theirs division and finally, the typical application of ANN will be discussed. Due to the diversity of architectures and adaptation algorithms, the ANNs are used in the broad spectrum of applications from the environmental processes modeling, through the optimization to quantitative structure-activity relationship (QSAR) methods. In addition, especially ANNs with Kohonen learning are very effective classification tool. The ANNs are mostly applied in cases, where the commonly used methods does not work.     

Proteome signatures—how are they obtained and what do they teach us?

The dawn of a new Proteomics era, just over a decade ago, allowed for large-scale protein profiling studies that have been applied in the identification of distinctive molecular cell signatures. Proteomics provides a powerful approach for identifying and studying these multiple molecular markers in a vast array of biological systems, whether focusing on basic biological research, diagnosis, therapeutics, or systems biology. This is a continuously expanding field that relies on the combination of different methodologies and current advances, both technological and analytical, which have led to an explosion of protein signatures and biomarker candidates. But how are these biological markers obtained? And, most importantly, what can we learn from them? Herein, we briefly overview the currently available approaches for obtaining relevant information at the proteome level, while noting the current and future roles of both traditional and modern proteomics. Moreover, we provide some considerations on how the development of powerful and robust bioinformatics tools will greatly benefit high-throughput proteomics. Such strategies are of the utmost importance in the rapidly emerging field of immunoproteomics, which may play a key role in the identification of antigens with diagnostic and/or therapeutic potential and in the development of new vaccines. Finally, we consider the present limitations in the discovery of new signatures and biomarkers and speculate on how such hurdles may be overcome, while also offering a prospect for the next few years in what could be one of the most significant strategies in translational medicine research.     

Kinship and sociality in coastal river otters: are they related?

Previous studies of coastal river otters (Lontra canadensis)in Prince William Sound, Alaska, USA, documented atypical socialorganization for mammals. Social groups were composed largelyof males, but some males remained solitary year-round and mostfemales were asocial. Because, in carnivores, groups are usuallycomposed of highly related individuals but group living alsoprovides advantages unrelated to kinship, we concurrently evaluatedthe role of relatedness and ecological benefits in socialityamong coastal river otters. By using DNA microsatellite analysisand radiotelemetry, we were able to reject the hypothesis thatsocial groups of otters were kin based. In addition, we foundno indication of kin avoidance, as would be expected from lowdispersal and high local competition. Sociality conferred noreproductive benefits or costs to otters; number of offspringand number of relatives in the population did not differ betweensocial and solitary animals. Solitary males were not older orlarger than were social males, and there was no relation betweenmale size and number of offspring, indicating that sexual selectiondid not mask a potential relation between sociality and reproductivesuccess. Among coastal river otters in this region, socialitycould be explained by the benefits obtained from cooperativeforaging on high-quality schooling pelagic fishes. Such benefitsdid not require association with kin, resulting in no selectionpressure for kin-based groups. The prediction that the degreeof sociality in the population will fluctuate relative to theabundance of schooling pelagic fishes merits further investigation.