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Wide diversity in structure and expression profiles among members of the Caenorhabditis elegans globin protein family
David Hoogewijs, Eva Geuens, Sylvia Dewilde, Andy Vierstraete, Luc Moens, Serge Vinogradov, Jacques R Vanfleteren
BMC Genomics , 2007, DOI: 10.1186/1471-2164-8-356
Abstract: All 33 C. elegans putative globin genes are transcribed. The translated sequences have the essential signatures of single domain bona fide globins, or they contain a distinct globin domain that is part of a larger protein. All globin domains can be aligned so as to fit the globin fold, but internal interhelical and N- and C-terminal extensions and a variety of amino acid substitutions generate much structural diversity among the globins of C. elegans. Likewise, the encoding genes lack a conserved pattern of intron insertion positioning. We analyze the expression profiles of the globins during the progression of the life cycle, and we find that distinct subsets of globins are induced, or repressed, in wild-type dauers and in daf-2(e1370)/insulin-receptor mutant adults, although these animals share several physiological features including resistance to elevated temperature, oxidative stress and hypoxic death. Several globin genes are upregulated following oxygen deprivation and we find that HIF-1 and DAF-2 each are required for this response. Our data indicate that the DAF-2 regulated transcription factor DAF-16/FOXO positively modulates hif-1 transcription under anoxia but opposes expression of the HIF-1 responsive globin genes itself. In contrast, the canonical globin of C. elegans, ZK637.13, is not responsive to anoxia. Reduced DAF-2 signaling leads to enhanced transcription of this globin and DAF-16 is required for this effect.We found that all 33 putative globins are expressed, albeit at low or very low levels, perhaps indicating cell-specific expression. They show wide diversity in gene structure and amino acid sequence, suggesting a long evolutionary history. Ten globins are responsive to oxygen deprivation in an interacting HIF-1 and DAF-16 dependent manner. Globin ZK637.13 is not responsive to oxygen deprivation and regulated by the Ins/IGF pathway only suggesting that this globin may contribute to the life maintenance program.Globins constitute a large super
Using Information and Communication Technology in Home Care for Communication between Patients, Family Members, and Healthcare Professionals: A Systematic Review  [PDF]
Birgitta Lindberg,Carina Nilsson,Daniel Zotterman,Siv S?derberg,Lisa Sk?r
International Journal of Telemedicine and Applications , 2013, DOI: 10.1155/2013/461829
Abstract: Introduction. Information and communication technology (ICT) are becoming a natural part in healthcare both for delivering and giving accessibility to healthcare for people with chronic illness living at home. Aim. The aim was to review existing studies describing the use of ICT in home care for communication between patients, family members, and healthcare professionals. Methods. A review of studies was conducted that identified 1,276 studies. A selection process and quality appraisal were conducted, which finally resulted in 107 studies. Results. The general results offer an overview of characteristics of studies describing the use of ICT applications in home care and are summarized in areas including study approach, quality appraisal, publications data, terminology used for defining the technology, and disease diagnosis. The specific results describe how communication with ICT was performed in home care and the benefits and drawbacks with the use of ICT. Results were predominated by positive responses in the use of ICT. Conclusion. The use of ICT applications in home care is an expanding research area, with a variety of ICT tools used that could increase accessibility to home care. Using ICT can lead to people living with chronic illnesses gaining control of their illness that promotes self-care. 1. Introduction Due to an ageing population and a shortage of hospital beds, it has become a challenge to find new ways to support and care for people with chronic illness living at home. Living with chronic illness changes the lives of those affected, who are often in need of support and nursing care in their homes [1–3]. eHealth has the potential to become a means of providing good care at home [4], which is especially challenging with regard to this emerging field [5]. eHealth refers to information and communication technology (ICT) tools and services for health, whether the tools are used behind the scenes by healthcare professionals or directly by patients and their relatives [6]. ICT tools can be used to access a wide variety of technological solutions for communication, including text messaging, gathering and monitoring data, diagnosis and treatment at distances, and retrieving electronic health records [5, 7]. According to the World Health Organization (WHO) [8], eHealth is used in the healthcare for transmission of digital data, including data stored and retrieved electronically to support healthcare, both at the local site and at a distance. E-Health includes the interaction between patients and health service providers or peer-to-peer
Molecular Structure and Diversity of PBAN/pyrokinin Family Peptides in Ants  [PDF]
Man-Yeon Choi,Robert K. Vander Meer
Frontiers in Endocrinology , 2012, DOI: 10.3389/fendo.2012.00032
Abstract: Neuropeptides are the largest group of insect hormones. They are produced in the central and peripheral nervous systems and affect insect development, reproduction, feeding, and behavior. A variety of neuropeptide families have been identified in insects. One of these families is the PBAN/pyrokinin family defined by a common FXPRLamide or similar amino acid fragment at the C-terminal end. These peptides, found in all insects studied thus far, have been conserved throughout evolution. The most well studied physiological function is regulation of moth sex pheromone biosynthesis through the pheromone biosynthesis activating neuropeptide (PBAN), although several developmental functions have also been reported. Over the past years we have extended knowledge of the PBAN/pyrokinin family of peptides to ants, focusing mainly on the fire ant, Solenopsis invicta. The fire ant is one of the most studied social insects and over the last 60 years a great deal has been learned about many aspects of this ant, including the behaviors and chemistry of pheromone communication. However, virtually nothing is known about the regulation of these pheromone systems. Recently, we demonstrated the presence of PBAN/pyrokinin immunoreactive neurons in the fire ant, and identified and characterized PBAN and additional neuropeptides. We have mapped the fire ant PBAN gene structure and determined the tissue expression level in the central nervous system of the ant. We review here our research to date on the molecular structure and diversity of ant PBAN/pyrokinin peptides in preparation for determining the function of the neuropeptides in ants and other social insects.
Genetic Diversity in New Members of the Reticulocyte Binding Protein Family in Thai Plasmodium vivax Isolates  [PDF]
Varakorn Kosaisavee, Usa Lek-Uthai, Rossarin Suwanarusk, Anne Charlotte Grüner, Bruce Russell, Francois Nosten, Laurent Rénia, Georges Snounou
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0032105
Abstract: Background Plasmodium vivax merozoites specifically invade reticulocytes. Until recently, two reticulocyte-binding proteins (Pvrbp1 and Pvrbp2) expressed at the apical pole of the P. vivax merozoite were considered to be involved in reticulocyte recognition. The genome sequence recently obtained for the Salvador I (Sal-I) strain of P. vivax revealed additional genes in this family, and in particular Pvrbp2a, Pvrbp2b (Pvrbp2 has been renamed as Pvrbp2c) and two pseudogenes Pvrbp2d and Pvrbp3. It had been previously found that Pvrbp2c is substantially more polymorphic than Pvrbp1. The primary goal of this study was to ascertain the level of polymorphism of these new genes. Methodology/Principal Findings The sequence of the Pvrbp2a, Pvrbp2b, Pvrbp2d and Pvrbp3 genes were obtained by amplification/cloning using DNA purified from four isolates collected from patients that acquired the infection in the four cardinal regions of Thailand (west, north, south and east). An additional seven isolates from western Thailand were analyzed for gene copy number variation. There were significant polymorphisms exhibited by these genes (compared to the reference Sal-I strain) with the ratio of mutations leading to a non-synonymous or synonymous amino acid change close to 3:1 for Pvrbp2a and Pvrbp2b. Although the degree of polymorphism exhibited by these two genes was higher than that of Pvrbp1, it did not reach the exceptional diversity noted for Pvrbp2c. It was interesting to note that variations in the copy number of Pvrbp2a and Pvrbp2b occurred in some isolates. Conclusions/Significance The evolution of different members of the Pvrbp2 family and their relatively high degree of polymorphism suggests that the proteins encoded by these genes are important for parasite survival and are under immune selection. Our data also shows that there are highly conserved regions in rbp2a and rbp2b, which might provide suitable targets for future vaccine development against the blood stage of P. vivax.
Extraordinary diversity among members of the large gene family, 185/333, from the purple sea urchin, Strongylocentrotus purpuratus
Katherine M Buckley, L Courtney Smith
BMC Molecular Biology , 2007, DOI: 10.1186/1471-2199-8-68
Abstract: The 185/333 genes are small (< 2 kb) with only two exons. Their extraordinary diversity was exemplified by 121 unique sequences identified from 171 cloned genes. Sequences from the second exons were aligned optimally by introducing large gaps, which defined blocks of sequence known as elements. Genes were defined by the presence or absence of elements. Phylogenetic analysis defined five intron types which, when combined with the exon element patterns resulted in 31 gene patterns, 14 of which were not described previously. Sequence diversity was present in all elements, and was higher in the intron than the exons. Repeats within the sequence facilitated multiple alignments, of which two were analyzed in detail. Although the two alignments differed in length, number of elements, and number of patterns, both were about equally accurate at describing the 185/333 sequences. The genes were closely linked and flanked by short repeats. The repeats within and between the genes may promote their diversification through gene conversion, recombination, and meiotic mispairing.The diversity of the 185/333 gene family represents an intriguing addition to what is known about the S. purpuratus immune response, and provides further evidence that invertebrate immune systems are neither simple nor static.Diversified immune responses provide hosts with advantages in the arms race against pathogens. Diversification of immune-response proteins enables organisms to detect and combat a broad array of pathogens with great precision. Although it was long believed that invertebrate organisms possessed simple, static immune systems, recent evidence from numerous organisms suggests that this may not be correct (reviewed in [1]). In the freshwater snail, Biomphalaria glabrata, a family of genes encodes fibrinogen-related proteins (FREPs), which contain IgSF and fibrinogen domains [2-9]. Although it is not known how many FREP genes are present in the snail genome, at least 13 subfamilies exist, wi
Relevance of the Diversity among Members of the Trypanosoma Cruzi Trans-Sialidase Family Analyzed with Camelids Single-Domain Antibodies  [PDF]
Laura Ratier, Mariela Urrutia, Gastón Paris, Laura Zarebski, Alberto C. Frasch, Fernando A. Goldbaum
PLOS ONE , 2008, DOI: 10.1371/journal.pone.0003524
Abstract: The sialic acid present in the protective surface mucin coat of Trypanosoma cruzi is added by a membrane anchored trans-sialidase (TcTS), a modified sialidase that is expressed from a large gene family. In this work, we analyzed single domain camelid antibodies produced against trans-sialidase. Llamas were immunized with a recombinant trans-sialidase and inhibitory single-domain antibody fragments were obtained by phage display selection, taking advantage of a screening strategy using an inhibition test instead of the classic binding assay. Four single domain antibodies displaying strong trans-sialidase inhibition activity against the recombinant enzyme were identified. They share the same complementarity-determining region 3 length (17 residues) and have very similar sequences. This result indicates that they likely derived from a unique clone. Probably there is only one structural solution for tight binding inhibitory antibodies against the TcTS used for immunization. To our surprise, this single domain antibody that inhibits the recombinant TcTS, failed to inhibit the enzymatic activity present in parasite extracts. Analysis of individual recombinant trans-sialidases showed that enzymes expressed from different genes were inhibited to different extents (from 8 to 98%) by the llama antibodies. Amino acid changes at key positions are likely to be responsible for the differences in inhibition found among the recombinant enzymes. These results suggest that the presence of a large and diverse trans-sialidase family might be required to prevent the inhibitory response against this essential enzyme and might thus constitute a novel strategy of T. cruzi to evade the host immune system.
Positive selection, molecular recombination structure and phylogenetic reconstruction of members of the family Tombusviridae: implication in virus taxonomy
Boulila, Moncef;
Genetics and Molecular Biology , 2011, DOI: 10.1590/S1415-47572011005000046
Abstract: a detailed study of putative recombination events and their evolution frequency in the whole genome of the currently known members of the family tombusviridae, comprising 79 accessions retrieved from the international databases, was carried out by using the recco and rdp version 3.31β algorithms. the first program allowed the detection of potential recombination sites in seven out of eight virus genera (aureusvirus, avenavirus, carmovirus, dianthovirus, necrovirus, panicovirus, and tombusvirus), the second program provided the same results except for genus dianthovirus. on the other hand, both methods failed to detect recombination breakpoints in the genome of members of genus machlomovirus. furthermore, based on fisher's exact test of neutrality, positive selection exerted on protein-coding genes was detected in 17 accession pairs involving 15 different lineages. except genera machlomovirus, and panicovirus along with unclassified tombusviridae, all the other taxonomical genera and the unassigned tombusviridae encompassed representatives under positive selection. the evolutionary history of all members of the tombusviridae family showed that they segregated into eight distinct groups corresponding to the eight genera which constitute this family. the inferred phylogeny reshuffled the classification currently adopted by the international committee on taxonomy of viruses. a reclassification was proposed.
On the Full Diversity Property of A Space-Frequency Code Family with Multiple Carrier Frequency Offsets in Cooperative Communication Systems  [cached]
Feng Tian,Xiang-Gen Xia,Wing-Kin Ma,P. C. Ching
Journal of Communications , 2010, DOI: 10.4304/jcm.5.4.317-331
Abstract: Space-frequency (SF) coded orthogonal frequency division multiplexing (OFDM) systems have been recently proposed for cooperative communications to achieve both full cooperative and full multipath diversities without the time synchronization requirement. In this paper, we show that the full diversity property still holds for a family of SF codes (rotation-based SF codes) when there are multiple carrier frequency offsets (CFOs) from relay nodes under the condition that the absolute values of the normalized CFOs are less than 0.5. We then prove that this full diversity property can be preserved if we seek to reduce the receiver complexity by using a zero forcing (ZF) method to equalize the multiple CFOs, before applying maximum likelihood (ML) decoding. Furthermore, by exploiting the properties of SF codes, we show that a specific permuted version of this family of SF codes can still achieve full diversity even when the inter-carrier interference (ICI) matrix is singular. This is possible as long as the maximum absolute value of the normalized CFOs is not less than 0.5. However, in this case the ZF method cannot be
New members of Datura family  [PDF]
Alexey Rosaev,Eva Plavalova
Physics , 2015,
Abstract: The problem of origin and age of asteroid families is studied very intensively. Youngest families are most interesting due to possibility of the reconstruction collisional history. Here we report about three new members of Datura Family
Toothbrush contamination in family members
Contreras,Adolfo; Arce,Roger; Botero,Javier Enrique; Jaramillo,Adriana; Betancourt,Marisol;
Revista clínica de periodoncia, implantología y rehabilitación oral , 2010, DOI: 10.4067/S0719-01072010000100004
Abstract: objective: the purpose of this study was to determine the bacterial contamination of toothbrushes in family members. materials and methods: one hundred and two healthy subjects were included in this descriptive study. every individual was examined clinically and microbiologically using the cpitn index and collecting subgingival plaque samples. each participant received a toothbrush for home use and after one month they returned it to the investigators. all toothbrushes were cultured to determine the presence of periodontopathic bacteria and enteric rods. wilkoxon signed rank test and t student test (p d"0.05) were used to compare differences in the subgingival microbiota and toothbrush contamination and cpitn index among family members. results: a high proportion of toothbrushes resulted highly contaminated with enteric rods (p d"0.001) compared to the subgingival environment where periodontopathic bacteria were more prevalent. the most frequent microorganisms found in toothbrushes used by parents and children for one month were enterobacteriaceae, pseudomonadaceae species (>50%) and fusobacterium spp (30%). conclusions: high levels of enteric rods were commonly detected in toothbrushes used for 1 month among members of the families. these opportunistic organisms may have an important role in oral infections including gingivitis and periodontitis. monthly replacement or disinfection of the toothbrush can reduce the risk of bacterial transmission/translocation and thus diminish the incidence of biofilm associated oral diseases.
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