Microalgae as a source of bioactive molecules – experience from cyanophyte research

Detrimental and beneficial properties of prokaryoticand eukaryotic microalgae may be qualifications givingthem posibillities for their biotechnologicalutilization. Phycotoxins and related products mayserve as material for useful drugs. Cyanotoxins arean example. Bioassay screening methods are used todetect specific biological activity (e.g. antibioticeffects). A study demonstrating antibacterialproperties among cyanophytes showed that these effectswere caused by substances produced by both toxigenicand non-toxigenic strains. Differences inbiosynthetic activity are influenced by the type ofclones and by the culture conditions (genetic andbiochemical variation). Experience of recentscreening (1997–1998) of compounds from cyanophytes –including 25 species from 14 genera – display thediscovery of more than 30 different antibioticsubstances. The further isolation of newpharmaceuticals from natural resources is becomingdifficult, if not uncommon species of producerorganisms are taken into consideration.     

Charles McLean Fraser (1872–1946) – his contributions to hydroid research and to the development of fisheries biology and academia in British Columbia

Hydrobiologia - Charles McLean Fraser (1872–1946) is best remembered for his work on hydroids, but he was also involved in a much broader range of activities during the development of marine...     

Isatis tinctoria – From the rediscovery of an ancient medicinal plant towards a novel anti-inflammatory phytopharmaceutical

An account on the reinvestigation of the old dye and medicinal plant Isatis tinctoria as an anti-inflammatory and current research on the active principles in woad is given. In a broad-based screening, a dichloromethane extract from the leaves displayed significant activities on several clinically relevant targets of inflammation. The cyclooxygenase-2 inhibitory principle was identified with the aid of HPLC-based activity profiling as the alkaloid tryptanthrin. In cell based assays, tryptanthrin strongly inhibited eicosanoid synthesis catalyzed by cyclooxygenase-2 and 5-lipoxygenase. A supercritical carbon dioxide extraction process was developed to replace the dichloromethane extract. Dichloromethane and carbon dioxide extracts showed in vivo anti-inflammatory activity in topical and oral application. With the aid of electrospray ionization liquid chromatography-mass spectrometry coupled skin microdialysis, tryptanthrin was found to penetrate the skin. The penetration from the extract was better than for the pure alkaloid. A screening of 67 woad samples of different geographic origin revealed up to 30-fold differences in tryptanthrin content in leaves. This revised version was published online in June 2006 with corrections to the Cover Date.     

The promise of e-Health – a Canadian perspective

Canadians value their health care system above any other social program. Canada's system of health care faces significant financial and population pressures, relating to cost, access, quality, accountability, and the integration of information and communication technologies (ICTs). The health-system also faces certain unique challenges that include care delivery within a highly decentralised system of financing and accountability, and care delivery to a significant portion of the population sparsely distributed across a landmass of 10 million square kilometres, in areas of extreme climatic conditions. All of these challenges are significant catalysts in the development of technologies that aim to significantly mitigate or eliminate these selfsame challenges.The system is undergoing widespread review, nationally, and within each province and territory, where the bulk of care provision is financed and managed. The challenges are being addressed by national, regional and provincial initiatives in the public, private and not-for-profit sectors.The promise of e-Health lies in the manner and degree to which it can mitigate or resolve these challenges to the health system and build on advancements in ICTs supporting the development of a health infostructure. Canada is actively developing and implementing technological solutions to deliver health information and health care services across the country. These solutions, while exciting and promising, also present new challenges, particularly in regard to acceptable standards, choice of technologies, overcoming traditional jurisdictional boundaries, up-front investment, and privacy and confidentially.Many organisations and governments are working to address these challenges. The Canadian Institute for Health Information (CIHI) will play an increasingly significant role in these initiatives, as the management of health information becomes a more crucial factor in the successful delivery of health care services in the new millennium.     

The world from a cat’s perspective – statistics of natural videos

The mammalian visual system is one of the most intensively investigated sensory systems. However, our knowledge of the typical input it is operating on is surprisingly limited. To address this issue, we seek to learn about the natural visual environment and the world as seen by a cat. With a CCD camera attached to their head, cats explore several outdoor environments and videos of natural stimuli are recorded from the animals perspective. The statistical analysis of these videos reveals several remarkable properties. First, we find an anisotropy of oriented contours with an enhanced occurrence of horizontal orientations, earlier described in the oblique effect as a predominance of the two cardinal orientations. Second, contrast is not elevated in the center of the images, suggesting different mechanisms of fixation point selection as compared to humans. Third, analyzing a sequence of images we find that the precise position of contours varies faster than their orientation. Finally, collinear contours prevail over parallel shifted contours, matching recent physiological and anatomical results. These findings demonstrate the rich structure of natural visual stimuli and its direct relation to extensively studied anatomical and physiological issues.     

Economics,human biology and inequality: A review of “puzzles” and recent contributions from a Deatonian perspective

The Nobel laureate Angus Deaton concentrated his work on puzzling developments and phenomena in economics. Puzzles are exciting elements in economics, because readers feel challenged by the question of how they can be solved. Among the puzzles analyzed by Deaton are: (1) Mortality increase of white, U.S. non-Hispanic men (2000 to today); (2) Why are height and income sometimes closely correlated, but not always?; (3) Height inequality among males and females; and (4) The Indian puzzle of declining consumption of calories during overall expenditure growth.This article reviews these “puzzles” and the main insights that Deaton derived from their discussion insofar as they pertain to the biological aspects of human development. I will focus on the field of this journal, Economics and Human Biology, in which Deaton has been very active over the last two decades. I will also document some of the responses by other scholars and their contributions to these puzzles, as they relate to the field of economics and human biology.     

The cave bear’s hibernation: reconstructing the physiology and behaviour of an extinct animal

Abstract

When studying an extinct species such as the cave bear (Ursus spelaeus ROSENMÜLLER 1794), it is possible to apply a variety of molecular biology techniques such as the study of stable isotopes or mitochondrial DNA (mDNA) to infer patterns of behaviour or physiology that would otherwise remain concealed. Throughout Europe and along time, differences in the isotopic values (δ¹³C and δ¹⁵N) of cave bears arise from environmental differences and the Pleistocene climatic evolution. The climate determines the hibernation length, during which the cave bears undergo a particular physiology that can be related to an increase in δ¹⁵N during climate cooling. In order to verify whether hibernation affected the isotopic values, we compared cave bears in different ontogenetic stages. The results show that perinatal values reflect the values for mothers during hibernation, while juveniles show differences in maternal investment. A previous study in the literature based on complete mitochondrial DNA sequences of several individuals collected from closely situated caves showed that each cave housed, almost exclusively, a single lineage of haplotypes. This pattern suggests extreme fidelity to the birth site, or homing behaviour, and that cave bears formed stable maternal social groups, at least for the purpose of hibernation. Studies of this type offer unexpected data on the palaeobiology of this extinct animal.     

Can yeast systems biology contribute to the understanding of human disease?

Saccharomyces cerevisiae is a unicellular eukaryal microorganism that has traditionally been regarded either as a model system for investigating cellular physiology or as a cell factory for biotechnological use, for example for the production of fuels and commodity chemicals such as lactate or pharmaceuticals, including human insulin and HPV vaccines. Systems biology has recently gained momentum and has successfully been used for mapping complex regulatory networks and resolving the dynamics of signal transduction pathways. So far, yeast systems biology has mainly focused on the development of new methods and concepts. There are also some examples of the application of yeast systems biology for improving biotechnological processes. We discuss here how yeast systems biology could be used in elucidating fundamental cellular principles such as those relevant for the study of molecular mechanisms underlying complex human diseases, including the metabolic syndrome and ageing.     

Establishing health benefits of bioactive food components: a basic research scientist’s perspective

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Review: Application of biotechnology to forestry – molecular biology of conifers

Genetic improvement in plantation forestry relies significantly on conventional breeding techniques which have been used extensively to improve various characteristics in forest trees such as growth and form, volume yield, resistance to pathogens and quality of the end product. This review concentrates on molecular techniques which have been used successfully in agriculture and which have more recently become available to improve further characteristics of forest trees and introduce new traits which are currently not available in the breeding population.     

Responding to the threat of bioterrorism: a microbial ecology perspective – the case of anthrax

Anthrax is a disease of herbivores caused by the gram-positive bacterium Bacillus anthracis. It can affect cattle, sheep, swine, horses and various species of wildlife. The routes for the spread among wildlife are reviewed. There are three kinds of human anthrax – inhalation, cutaneous, and intestinal anthrax – which differ in their routes of infection and outcomes. In the United States, confirmation of cases is made by the isolation of B. anthracis and by biochemical tests. Vaccination is not recommended for the general public; civilians who should be vaccinated include those who, in their work places, come in contact with products potentially contaminated with B. anthracis spores, and people engaged in research or diagnostic activities. After September 11, 2001, there were bioterrorism anthrax attacks in the United States: anthrax-laced letters sent to multiple locations were the source of infectious B. anthracis. The US Postal Service issued recommendations to prevent the danger of hazardous exposure to the bacterium. B. anthracis spores can spread easily and persist for very long times, which makes decontamination of buildings very difficult. Early detection, rapid diagnosis, and well-coordinated public health response are the key to minimizing casualties. The US Government is seeking new ways to deter bioterrorism, including a tighter control of research on infectious agents, even though pathogens such as B. anthracis are widely spread in nature and easy to grow. It is necessary to define the boundary between defensive and offensive biological weapons research. Deterring bioterrorism should not restrict critical scientific research. Electronic Publication     

From molecules to the biosphere: Nikolai V. Timoféeff-Ressovsky’s (1900–1981) research program within a totalitarian landscape

Nikolai Vladimirovich Timoféeff-Ressovsky was one of the key figures in the Synthetic Theory of Evolution. Living and researching under what was arguably the two most powerful and cruel totalitarian regimes in human history, the Third Reich and the Soviet Union, Timoféeff-Ressovsky succeeded in developing an ambitious research program aiming to explain evolution on all major levels, from the molecular-genetic, the populational, and the biogeocenotic to the level of the entire Biosphere. Yet his scientific biography remains largely unwritten and his role under totalitarianism, especially in Nazi Germany, remains highly controversial. Here we approach the problem of his hypothetical cooperation with Nazi authorities examining both the crucial episodes of his biography and summarizing the development of his research program. We conclude that the key decisions he made reflected the specificity of his research program that was focused on the fundamental questions of evolutionary biology.     

Is systems biology a promising approach to resolve controversies in cancer research?

ABSTRACT: At the beginning of the 21st century cancer research has reached an impasse similar to that experienced in developmental biology in the first decades of the 20th century when conflicting results and interpretations co-existed for a long time until these differences were resolved and contradictions were eliminated. In cancer research, instead of this healthy "weeding-out" process, there have been attempts to reach a premature synthesis, while no hypothesis is being rejected. Systems Biology could help cancer research to overcome this stalemate by resolving contradictions and identifying spurious data. First, in silico experiments should allow cancer researchers to be bold and a priori reject sets of data and hypotheses in order to gain a deeper understanding of how each dataset and each hypothesis contributes to the overall picture. In turn, this process should generate novel hypotheses and rules, which could be explored using these in silico approaches. These activities are significantly less costly and much faster than "wet-experiments". Consequently, Systems Biology could be advantageously used both as a heuristic tool to guide "wet-experiments" and to refine hypotheses and test predictions.     

Toward a multifaceted understanding of plants’ adaptation mechanisms

Journal of Plant Research -     

From Alzheimer to Huntington: why is a structural understanding so difficult?

An increasing family of neurodegenerative disorders such as Alzheimer's, Parkinson's and Huntington's diseases, prion encephalopathies and cystic fibrosis is associated with aggregation of misfolded polypeptide chains which are toxic to the cell. Knowledge of the three-dimensional structure of the proteins implicated is essential for understanding why and how endogenous proteins may adopt a non-native fold. Yet, structural work has been hampered by the difficulty of handling proteins insoluble or prone to aggregation, and at the same time that is why it is interesting to study these molecules. In this review, we compare the structural knowledge accumulated for two paradigmatic misfolding disorders, Alzheimer's disease (AD) and the family of poly-glutamine diseases (poly-Q) and discuss some of the hypotheses suggested for explaining aggregate formation. While a common mechanism between these pathologies remains to be proven, a direct comparison may help in designing new strategies for approaching their study.     

Public involvement in pharmacogenomics research: a national survey on patients’ attitudes towards pharmacogenomics research and the willingness to donate DNA samples to a DNA bank in Japan

To assess the attitude of Japanese patients towards pharmacogenomics research and a DNA bank for identifying genomic markers associated with adverse drug reactions (ADRs) and their willingness to donate DNA samples, we conducted a survey of 550 male and female patients. The majority of the respondents showed a positive attitude towards pharmacogenomics research (87.6%) and a DNA bank (75.1%). The willingness to donate DNA samples when experiencing severe ADRs (55.8%) was higher than when taking medications (40.4%). Positive attitudes towards a DNA bank and organ donation were significantly associated with an increased willingness to donate. Though the level of positive attitude in the patient population was higher than that in the general public in our former study (81.0 and 70.4%, respectively), the level of the willingness of patients to donate was 40.4% when taking medications and 55.8% when experiencing severe ADRs which was lower than that of the general public in our former study (45.3 and 61.7%). The results suggested that the level of true willingness in the patient population was lower than that of the general public considering the fictitious situation presented to the public (to suppose that they were patients receiving medication). It is important to assess the willingness of patients who are true potential donors, not the general public.