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[
Dermatol Clin,
1989]
It is apparent that there are many similarities among the various filariae. Besides a common life cycle, with an arthropod vector and human hosts, there are similarities in the diseases that they produce. This clinical picture takes one of two main courses: (1) characteristic disease produced by the presence of adult nematodes in their target tissue, which distinguishes typical cases for each of the filariae, and (2) the systemic hypersensitivity reactions to the circulating microfilaria, which tend to be similar. The characteristic feature of Wuchereria bancrofti is genital disease with funiculitis and hydrocele and less often elephantiasis. For Brugia malayi it is elephantiasis of the distal leg or arm, usually leaving the knee or elbow uninvolved with normal contours. Brugia timori, restricted to just a few islands of Indonesia, produces elephantiasis similar to that of Brugia malayi, but with its characteristic descending lymphadenitis. Loa loa is best known for the Calabar swelling, or angioedema, that it produces, although other filariae can induce similar reactions. Both Loa loa and Dirofilaria tenuis cause macroscopic, subconjunctival eyeworms. Clinical disease from onchocerciasis takes four predominant forms: eye disease, lymphadenitis, subcutaneous nodules (onchocercomata), and a pruritic, hypopigmented, or hyperpigmented papular dermatitis.
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[
Br J Dermatol,
2020]
Onchocerciasis is a neglected tropical disease caused by a nematode parasite, Onchocerca volvulus, and transmitted by bites of Simulium blackflies which breed near fast-flowing rivers. In humans thousands of microfilariae (immature worms) migrate to the skin and eyes where they cause pathology. Historically, much research was devoted to the serious effect of blindness, from which the disease earns its alternative name of "river blindness". Mapping the burden of onchocercal skin disease (OSD) was expedited by the development of a clinical classification and grading system which facilitated comparison of data from different countries. After successful field-testing in Nigeria, the classification scheme was used in a multicountry study in seven endemic sites, to estimate the true burden of OSD across Africa. High levels of OSD were found, affecting 28% of the population. A new control programme, the African Programme for Onchocerciasis Control (APOC) was launched in 20 countries using annual doses of ivermectin, donated by Merck & Co., Inc. The multicountry study also found a close correlation between the levels of itching and OSD with the level of endemicity, as determined by the prevalence of onchocercal nodules. This enabled APOC to use Rapid Epidemiological Mapping of Onchocerciasis (REMO) which entailed identifying likely vector breeding sites near rivers, then sampling 50 adult males in nearby villages to determine the prevalence of nodules and delineate which villages required treatment. Onchocerciasis is now targeted for elimination in Africa, and the challenge is to complete Onchocerciasis Elimination Mapping (OEM) of hypoendemic areas using serology.
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[
Worm Breeder's Gazette,
1990]
The Worm Community System project is building an interactive computer environment that will enable biologists to easily access knowledge about C. elegans and to record their observations about this knowledge. The goal is to make the personal computer in the laboratory of every worm biologist a portal into an information space of 'all' the information about the worm and 'all' the annotations on this information. You will be able to rapidly browse the information, run analysis programs on selected units, group selected units into new information, and share these groupings with the worm community. This project is underway in the Computer and Biological Systems Laboratory at the University of Arizona at Tucson, whose mission is to bring computer science research to bear on problems of biological science by building computer systems which interactively manipulate knowledge about biological systems. The project is funded by a major grant from the National Science Foundation sponsored by both the Computer and Biological Science Directorates. There are close collaborations with the mapping and sequencing projects at MRC-LMB and Washington University and with the CGC. The worm information space will comprise as much of the knowledge of the worm community as is possible to capture in electronic form. Eventually, the data types will include text, graphics, and image, spanning the following sources. Experimental data will include genomic data (gene list, genetic map, physical map, DNA sequences) and anatomical data (cell list, cell lineage, wiring diagram). Literature information will include the bibliography, abstracts from Medline, scanned full-text and page images, this Gazette, Worm Meeting proceedings, and the Worm Book. Informal information will include lab directories, strain lists, and protocols, and may include images of micrographs and gels. Much of the informal material, the annotations, and the connections between units of information will hopefully be entered by you as members of the worm community. The worm information space will be accessible via any personal computer running an X-windows server which is connected across the national NSFNET network to machines containing the data and the software. Associative keyword search will be supported, as will connection links to related information such as genes referred to in literature or map regions containing genes. Groups of information will be selectable to be passed into external programs for analysis or transformed into other information units for later access. The system is thus meant to serve a wide variety of the communication needs of the worm community, both retrieval and analysis, as well as rapid sharing of knowledge with others. An early prototype of the system is running at Arizona. It contains genomic data and literature abstracts, and it supports rapid browsing and sharing of information stored locally. It will be placed into the labs of initial users by the end of this year. This version requires a local Unix workstation to run the software, although the display can be run on an Apple Macintosh running an X-windows terminal emulator. Subsequent versions will relax this requirement. The distribution is currently being limited to computer sophisticates who are willing to invest time in using and improving an incomplete system. This will permit rapid evolution of the system into a form suitable for use by the entire worm community. People with interest in serving as initial users are encouraged to contact Bruce Schatz via the Internet as 'schatz@cs.arizona.edu'. Also requested from anyone are pointers to data already available in electronic form and comments on useful software functionality and data sources. Carrying out this project to provide electronic support to continue the special cooperation within the worm community will only be possible with the active help and support of all of you.
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[
Br J Pharmacol,
2008]
RIC-3 is a transmembrane protein which acts as a molecular chaperone of nicotinic acetylcholine receptors (nAChRs). For some nAChR subtypes (such as homomeric alpha7 neuronal nAChRs), RIC-3 is required for efficient receptor folding, assembly and functional expression. In contrast, for other nAChR subtypes (such as heteromeric alpha4beta2 neuronal nAChRs) there have been reports that RIC-3 can both enhance and reduce levels of functional expression. There is also evidence that RIC-3 can modulate maturation of the closely related 5-hydroxytryptamine (5-HT) receptor (5-HT(3)R). As with heteromeric nAChRs, apparently contradictory results have been reported for the influence of RIC-3 on 5-HT(3)R maturation in different expression systems. Recent evidence indicates that these differences in RIC-3 chaperone activity may be influenced by the host cell, suggesting that other proteins may play an important role in modulating the effects of RIC-3 as a chaperone. RIC-3 was originally identified in the nematode Caenorhabditis elegans as the protein encoded by the gene
ric-3 (resistance to inhibitors of cholinesterase) and has subsequently been cloned and characterized from mammalian and insect species. This review provides a brief history of RIC-3; from the identification of the
ric-3 gene in C. elegans in 1995 to the more recent demonstration of its activity as a nAChR chaperone.British Journal of Pharmacology advance online publication, 4 February 2008; doi:10.1038/sj.bjp.0707661.
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[
International C. elegans Meeting,
1991]
We are building an interactive computer environment to easily manipulate 'all' knowledge about C. elegans. The goal is to make the personal computer in the laboratory of every worm biologist a portal into an information space of interconnected worm knowledge, from established facts to unwritten folklore. System features include retrieval and analysis of archival data and published literature, and incorporation of personal annotations and unpublished materials. The current information space incorporates a wide variety of knowledge, including data obtained from curators and software integrated into the environment. The genomic data (gene list, genetic map, physical map, DNA sequences) was originally obtained from Mark Edgley (CGC), John Sulston (MRC), and Genbank, and displayed with our own software. To track the most current versions, this is being replaced by the acedb program written by Richard Durbin and Jean Thierry-Mieg for the MRC/WUSTL sequencing project, with interfaces defined to provide smooth integration. The gm exon map displayer of Chris Fields, et. al. is also available. The formal literature is the CGC bibliography supplemented with abstracts from Medline and Biosis (some 716 of 1298). For the informal literature, we are scanning in the Worm Breeder's Gazette and will shortly have available the complete contents of all issues, including both text and figures. Other incorporated data includes the lab directory and strain list. The current software environment runs under X-windows on a computer connected via network to a UnixT(tm) machine; it has been run on Sun and Dec workstations and Apple MacintoshesTM. Fast interactive browsing is supported, including searching of text and following of connections. Extensive support is provided for users to add their own data and connections. The hope is to capture the informal knowledge of the worm by permitting the members of the community to each add their own specialized knowledge. Information units from multiple sources can be selected, e.g. genes, clones, abstracts, then grouped into a new unit with text annotation to be shared with the rest of the community. We will shortly be experimenting with an electronic version of the WBG where these annotations are articles with live references, which can be followed back into the original electronic sources, and with adding unpublished material, such as restriction maps and individual strains. The current prototype is running in a few friendly labs, both locally and across the Internet. We are hoping to gain sufficient feedback and additional users to learn how to improve the system so that it will be useful and available to everyone in the worm community.
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[
International C. elegans Meeting,
1999]
Ankyrins are cortical cytoskeletal proteins involved in anchoring the cytoskeleton to the plasma membrane. Mutations in the
unc-44 ankyrin gene result in axon outgrowth and guidance defects. We have taken several approaches to characterize the
unc-44 ankyrins. Polyclonal antibodies prepared against the spectrin-binding domain (AO271 Ab) and the STEP domain (AO346 Ab) were affinity purified against recombinant antigen on Western blots. In freeze-fractured worms, AO346 Ab stained the hermaphrodite nervous system, including the nerve ring, nerve cords, commissures, and ganglia. Staining occurred along nerve processes and at the periphery of the cell bodies. In males, the nervous system stained, including tail ray neurons. In comma stage embryos, staining was observed in the animal anterior. In later stage embryos, strong staining was observed in the nerve ring and nerve cords. Using the AO271 Ab, staining was observed at the periphery of many cell types, which is consistent with expected localization of ankyrins in the cortical cytoskeleton. Staining was also observed in the oocyte cytoplasm. While it cannot be ruled out that the interaction may be non-specific or due to residual anti-yolk Abs not removed during affinity purification, it is intriguing to note that there are abundant cytoplasmic ankyrins lacking ankyrin repeat domains in vertebrate kidney cells. In order to understand the biochemical properties of UNC-44 ankyrins, we started to purify C. elegans ankyrins. Starting from protocols for the purification of vertebrate red blood cell or brain ankyrins, attempts were made to purify UNC-44 ankyrins as membrane-associated proteins, followed by differential dissociation from the membrane fraction. The various ankyrin isoforms displayed weak partitioning by differential dissociation. The large AO13 ankyin isoform generally fractionated into the pellet and required 7 M urea for partial solubilization. The current strategy is to purify the ankyrins by affinity chromatography on a bovine spectrin column. Because vertebrate brain ankyrin is glycosylated, we are testing the ability of worm ankyrins to bind to a wheat germ-affinity column.
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[
Br J Dermatol,
2005]
Summary The nematode Caenorhabditis elegans has proven a robust genetic model for studies of aging and the roles of stress. In this review we focus on the genetics of select long-lived and short-lived mutants of C. elegans that have proven useful in revealing the relationships that exist between oxidative stress and life span. The former are known to be controlled by an insulin/insulin-like signaling pathway, while the latter are affected by mitochondrial functions.
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[
International C. elegans Meeting,
1997]
In order to obtain the maximum information in the shortest time, C. elegans sequencing was initiated within the gene-rich regions of the genome, which are estimated to contain over 80% of genes. Encompassing 60 MB, this region also had the advantage of being well represented in cosmid contigs. Sequencing of this 60 Mb region is now essentially complete. Of the remaining sequence approximately 20 Mb is only represented by YAC clones. Thus it was imperative that new sequencing strategies were developed so that YACs could be utilised as part of the initial sequencing substrate. During 1996, production scale methodologies were established in both labs to allow a shotgun sequencing approach to be efficiently applied to YAC clones. The major difficulties are handling the small amount of DNA that can be recovered from yeast hosts and elimination of yeast contamination. However, by double gel purification of YAC isolates, and the use of yeast 'window' strains where necessary, yeast sequence contamination can be reduced below 10%. pUC is better than M13 for providing adequate libraries from small amounts of DNA. (The Sanger Centre uses exclusively pUC, while the Genome Sequencing Center uses a mixture of pUC and M13). The pUC clones have the additional advantages of bridging inverted repeats (which M13 cannot handle) and of providing an extensive check on assembly from forward and reverse read pairs. Our strategy for sequencing the final 40 Mb will be to shotgun sequence YAC clones in conjunction with any underlying cosmid clones. This strategy is proceeding well and at the time of writing more than 40 YAC clones are being sequenced. We estimate that approximately 150 YACs will need to be shotgunned to complete the genomic sequence.
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[
Biophys J,
2011]
We report superresolution fluorescence microscopy in an intact living organism, namely Caenorhabditis elegans nematodes expressing green fluorescent protein (GFP)-fusion proteins. We also superresolve, by stimulated emission depletion (STED) microscopy, living cultured cells, demonstrating that STED microscopy with GFP can be widely applied. STED with GFP can be performed with both pulsed and continuous-wave lasers spanning a wide wavelength range from at least 556-592nm. Acquiring subdiffraction resolution images within seconds enables the recording of movies revealing structural dynamics. These results demonstrate that numerous microscopy studies of live samples employing GFP as the marker can be performed at subdiffraction resolution.
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[
Curr Biol,
2010]
The development of neuronal dendritic trees involves positive and negative control of growth and branching, as well as modulation of the spacing and orientation of branches. A new study reveals the importance of a membrane fusogen in the dendrite arborization of a pair of highly-branched worm sensory neurons.