1,720,962 research outputs found
Resveratrol Prolongs Lifespan and Retards the Onset of Age-Related Markers in a Short-Lived Vertebrate
Full text linkSummaryResveratrol, a natural phytoalexin found in grapes and red wine [1], increases longevity in the short-lived invertebrates Caenorhabditis elegans and Drosophila [2–5] and exerts a variety of biological effects in vertebrates, including protection from ischemia and neurotoxicity [6–10]. Its effects on vertebrate lifespan were not yet known. The relatively long lifespan of mice, which live at least 2.5 years [11], is a hurdle for life-long pharmacological trials. Here, the authors used the short-lived seasonal fish Nothobranchius furzeri with a maximum recorded lifespan of 13 weeks in captivity [12, 13]. Short lifespan in this species is not the result of spontaneous or targeted genetic mutations [14], but a natural trait correlated with the necessity to breed in an ephemeral habitat and tied with accelerated development and expression of ageing biomarkers at a cellular level [12, 13]. Resveratrol was added to the food starting in early adulthood and caused a dose-dependent increase of median and maximum lifespan. In addition, resveratrol delays the age-dependent decay of locomotor activity and cognitive performances and reduces the expression of neurofibrillary degeneration in the brain. These results demonstrate that food supplementation with resveratrol prolongs lifespan and retards the expression of age-dependent traits in a short-lived vertebrate
Killi-Data News
Full text linkThis is the first edition of a new publication for KDI: Killi- Data News. It offers a brief review of killifish research as well as a round up of interesting anecdotal reports by killlifish hobbyists that may be of interest to professional scientists as well as other hobbyists. A Killi-Data News edition is planned for every 3 months depending on availability of content. The current format was chosen for easier on-screen reading. The font is legible when the document is printed 2-pages to a sheet of paper. Authors are encouraged to submit their own article summaries so as to best emphasize the significance of their work
Control analysis of adrenal Sseroidogenesis
Full text linkThesis (MSc (Biochemistry))--University of Stellenbosch, 2004.This study describes:
1. Investigation of product inhibition regarding the metabolism of progesterone in ovine
adrenal micosomes.
2. The employment of novel cell culture techniques to study the effect of CYP17 and CYP21
concentration on adrenal progesterone metabolism.
3. The formulation of a mathematical model describing the behaviour of the observed results
in point 2
Killi-Data News (Summer)
Full text linkOver the last three months several interesting and exciting pa- pers have been published. By now most of you have heard the Nothobranchius fish poo news emanating from the Valenzano lab. That paper is reviewed and certainly has repercussions for the health of our captive fish. Polaçik et al have published interesting data with ramifications as to how we breed and incubate annual killifish. The big news in this issue is the paper from the Reznick lab which Jean Huber reviews. The contents of that paper goes to the heart of the question of just what a killifish is. The phylogenies from Reznick et al may fundamentally transform our understanding of the origin and evolutive timing of Cyp- rinodontiformes (including killifish). Once again, there are several papers on Fundulus heteroclitus on topics of genetics, hybrid zones, evolution and environmental toxicology. Again, there are new species of Melanorivulus-group and I think we can expect more species. There are three articles on the embryonic development of South American Annual fish: Austrofundulus, Austrolebias and Millerichthys. Martin & Podrabsky review the concept of developmental arrest and define the terms diapause, delayed hatching etc. . . as well as review the knowledge of diapause learned from Austrofundulus. I hope you enjoy this issue and put the information to some use in your fishrooms and/or research projects
Killi-Data News (Spring)
Full text linkThis is the start of Killi-Data News’ second year. In this first issue of the year we have the usual review of research pub- lications as well as input from Martin Reichard on his lab’s Nothobranchius research. Martin is responding to my reviews of his lab’s work in the previous edition. I am serious about making sure the content in this newsletter is reliable but I erred in the previous edition and Martin has written extensively to correct my mistake in the section “Erratum”. This reply is welcomed and owed to readers. I must confess that I don’t know everything and my area of scientific expertise is mostly restricted to histology and protein chemistry. When I comment on subjects outside of my area of expertise I tread on unfamiliar ground and am not much more expert than someone randomly selected off the street. For this reason we still need to expand the pool of reviewers for Killi-Data News. I am happy to report that Andy Patel and Manuel Zapater Galve have volunteered to review papers for us. Andy brings with him expertise in animal behavior and Manuel in physiol- ogy and ecology. We still need reviewers to eco-toxicology. Andrei Tatarenkov is reviewing a paper on Kryptolebias. Andrei is the expert on these fish and right now there is a need for expert opinion on these fish. It was hoped that An- drei would tell us a bit about Kryptolebias phylogenetics and address the issue of the ranges of K. hermaphroditus (sensu Costa) and marmoratus. As it turns out Andrei et al have a
manuscript in production and have decided to hold off until after the paper’s publication to comment on this subject. There has been an appeal by Prof Ryan Earley for help with a large evolutionary ecology study he and collaborators are undertaking. His letter follows in the next section. There aren’t a lot of papers this quarter due to the cut-off for inclusion in the newsletter. We had decided to run from December first up until February first for the three months of the Spring quarter. As consequence this issue is a bit thin but already there has been a flurry of papers published from the second of February. The next issue will be much thicker
Killi-Data News (Winter)
Full text linkThis is the fourth edition, and concluding issue of the first volume, of Killi-Data News and I am happy that it has been well received by readers. At 25 pages this issue is a bit thin- ner than the last but this is because we agreed to make the cut-off for submissions the 1 st of December so we could get this edition out by the New Year. This is an exciting edition full of new species descrip- tions and analyses that will keep taxonomists busy for years to come. Costa has given us two molecular phylogenies on Melanorivulus as well as an exciting paper on Kryptolebias. Two new Nothobranchius are described and both papers will no doubt pave the way for further descriptions. There are two new publications on Mexican killifish. One is very depressing reading and serves to highlight the plight of Mexican killi- fish. Perhaps there is a partner for conservation in Rescuing Profundulus oaxacae? This edition we are joined by Mark Peterson who has agreed to review ecology papers. Help is still needed with the following topics:
• Phylogenetics and Genomics research papers
• Ecotoxicology
• Behavioral research
If you would like to join the editorial team please email me: killifl[email protected]. As papers are published they will be made available to the reviewers; or if you come across a paper send me a review. You can use this issue as
a guide to the workload per paper. I know we professional researchers are constantly reading, and probably reading the interesting papers in this edition before they see it here. It doesn’t take long to lets us know what you learnt from the paper and why it would be important to others to read. The Molecular Platform project is growing steadily (http: //www.killi-data.org/list-names-molecular.php). We re- ceived several rare specimens of South American Annual from Didier Pillet as well a specimen of Pronothobranchius seymouri from Amer Faour—which has already been shared with two research labs. We have also been offered specimens from several big breeders: Lou Hersch (AKA), Willem-Jan Hoet- mer (KFN), Morgens Juhl (SKS), Jurij Phunkner (BKA) and Jeff Wasley (AKA). We are optimistic that the project will continue to grow and more researchers will make use of this facility. I hope you will enjoy this issue and continue your support of KDI. May you have a prosperous new year
Killi-Data News (Fall)
Full text linkMany interesting papers have been published over the last three months. The large volume of papers coupled with the start of the new college semester (and the workload it brings) delayed this issue of Killi-Data News. But better late than never—or so I hope! In this issue Richard van der Laan provides an insightful review of the recent Aphanius papers as to their taxonomic implications and questions. The systematic issues he raises show the importance of the Molecular project: we need to get more samples of the various cyprinodontiforme families to resolve unsettled systematic and taxonomic issues. In the Next issue Andrei Tatarenkov (and colleagues) will tell us about Kryptolebias distribution and evolution—now that the official research paper has been published. In the paper they have divided he mangrove killifish into three major clades by molecular phylogenetics. They have ana- lyzed several new populations. They have decided to allocate the names bonairensis, hermaphroditus and marmoratus to the clades. Also, Bettina Reichenbacher will also offer some in- sight into the new, monotypic, genus of killifish discovered in the high Andes of Chile, Pseudorestias lirimensis. We hope you will enjoy this issue and find something useful you can use in your fishroom or research
A study of neurodegeneration and neuroprotection in Nothobranchius guentheri
No full textIncludes abstract.Includes bibliographical references.This thesis details a study into aging-related neurodegeneration of Nothobranchius guentheri and the affect of resveratrol-treatment on this neurodegeneration. The goal of the study was to identify cytological probes by which to study neurodegeneration and use these to deliver novel findings pertaining to Nothobranchius aging and resveratrol induced neuroprotection
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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