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101.
In this study we describe the isolation and characterisation of the parathyroid hormone-related protein (PTHrP) gene from the teleost Fugu rubripes. The gene has a relatively simple structure, compared with tetrapod PTHrP genes, composed of three exons and two introns, encompassing 2.25 kb of genomic DNA. The gene encodes a protein of 163 amino acids, with a putative signal peptide of 37 amino acids and a mature peptide of 126 amino acids. The overall homology with known tetrapod PTHrP proteins is low (36%), with a novel sequence inserted between positions 38 and 65, the absence of the conserved pentapeptide (TRSAW) and shortened C-terminal domain. The N-terminus shows greater conservation (62%), suggesting that it may have a hypercalcaemic function similar to that of tetrapod PTHrP. In situ localisation and RT–PCR have demonstrated the presence of PTHrP in a wide range of tissues with varying levels of expression. Sequence scanning of overlapping cosmids has identified three additional genes, TMPO, LDHB and KCNA1, which map to human chromosome 12, with the latter two mapping to 12p12-11.2. PTHrP in human also maps to this chromosome 12 sub-region, thus demonstrating conservation of synteny between human and Fugu. 相似文献
102.
CD4(+) T-cell-mediated antiviral protection of the upper respiratory tract in BALB/c mice following parenteral immunization with a recombinant respiratory syncytial virus G protein fragment 总被引:1,自引:0,他引:1 下载免费PDF全文
Plotnicky-Gilquin H Robert A Chevalet L Haeuw JF Beck A Bonnefoy JY Brandt C Siegrist CA Nguyen TN Power UF 《Journal of virology》2000,74(8):3455-3463
We analyzed the protective mechanisms induced against respiratory syncytial virus subgroup A (RSV-A) infection in the lower and upper respiratory tracts (LRT and URT) of BALB/c mice after intraperitoneal immunization with a recombinant fusion protein incorporating residues 130 to 230 of RSV-A G protein (BBG2Na). Mother-to-offspring antibody (Ab) transfer and adoptive transfer of BBG2Na-primed B cells into SCID mice demonstrated that Abs are important for LRT protection but have no effect on URT infection. In contrast, RSV-A clearance in the URT was achieved in a dose-dependent fashion after adoptive transfer of BBG2Na-primed T cells, while it was abolished in BBG2Na-immunized mice upon in vivo depletion of CD4(+), but not CD8(+), T cells. Furthermore, the conserved RSV-A G protein cysteines and residues 193 and 194, overlapping the recently identified T helper cell epitope on the G protein (P. W. Tebbey et al., J. Exp. Med. 188:1967-1972, 1998), were found to be essential for URT but not LRT protection. Taken together, these results demonstrate for the first time that CD4(+) T cells induced upon parenteral immunization with an RSV G protein fragment play a critical role in URT protection of normal mice against RSV infection. 相似文献
103.
E. M. Southgate M. R. Davey J. B. Power R. J. Westcott 《In vitro cellular & developmental biology. Plant》1998,34(3):218-224
Summary Techniques for transforming intact tissues of cereals were evaluated for their efficacy in transforming immature embryos and
Type II callus of maize (Zea mays L.). The techniques used were particle bombardment, tissue electroporation, tissue electrophoresis, and silicon carbide fibers.
Each method was assessed in terms of transient β-glucuronidase (GUS) expression. High levels of GUS expression were observed
in A188 Type II callus using both tissue electroporation and particle bombardment, with means of 417.8 and 954.5 blue expression
units (beu) per g fresh weight (FW) callus, respectively. Only particle bombardment resulted in high transient gene expression
in immature embryos, with a mean transformation frequency of 34.8 b.e.u. per embryo. Very low levels of GUS expression were
achieved with silicon carbide-mediated gene transfer, even when employing tissues used in the original publication (Black
Mexican Sweet suspension cells). GUS expression was not obtained following tissue electrophoretic gene delivery. 相似文献
104.
Expression of a chitinase transgene in rose (Rosa hybrida L.) reduces development of blackspot disease (Diplocarpon rosae Wolf) 总被引:12,自引:0,他引:12
Marchant Robert Davey Michael R. Lucas John A. Lamb Chris J. Dixon Richard A. Power J. Brian 《Molecular breeding : new strategies in plant improvement》1998,4(3):187-194
Blackspot, caused by the Ascomycete fungus Diplocarpon rosae, is the most widespread and pernicious disease of cultivated roses. While some species of rose possess resistance to D. rosae, none of the modern-day rose cultivars are fully resistant to the pathogen. In the current study, Biolistic gene delivery was used to introduce a rice gene, encoding a basic (Class I), chitinase into embryogenic callus of the blackspot-susceptible rose (Rosa hybrida L.) cv. Glad Tidings. The plasmid used for transformation carried the neomycin phosphotransferase (nptII) gene facilitating the selection and regeneration of transgenic plants on medium containing 250 mg/l kanamycin. Southern analysis confirmed integration of 2–6 copies of the chitinase gene into the rose genome; gene expression was confirmed by enzyme assay. Bioassays demonstrated that expression of the chitinase transgene reduced the severity of blackspot development by 13–43%. This degree of resistance to the pathogen correlated with the level of chitinase expression in the transgenic rose plants. The introduction of disease defence genes into rose provides a method of producing blackspot-resistant rose cultivars sought by breeders and growers. 相似文献
105.
R S Power H E David M H A Z Mutwakil K Fletcher C Daniells M A Nowell J L Dennis A Martinelli R Wiseman E Wharf D I de Pomerai 《Journal of biosciences》1998,23(4):513-526
This paper reviews the current status of nematodes with stress-inducible transgenes as biosensors responsive to a range of
external stressors, e.g., soil or water pollution, microwave radiation or immunological attack. TransgenicCaenorhabditis elegans carrying reporter genes under heat shock promoter control express reporter products only under stressful conditions. Although
relatively insensitive to single metal ions, these worms respond to complex mixtures present in metal-contaminated watercourses
and to laboratory mixtures containing similar constituents, but not to any of their components singly at comparable concentrations.
Responses to metal mixtures are enhanced by a non-ionic surfactant, Pluronic F-127. Metals taken up by food bacteria and insoluble
metal carbonates can also evoke stress responses, both in soil and aqueous media. However, high concentrations of added metals
are needed to induce clear-cut responses in soil, owing to metal sorption onto clays and organic matter. Transgenic worms
are also stressed by exposure to microwave radiation; pulsed signals generate responses that diminish markedly with distance
from the source. Finally, stress responses are inducible by anti-epicuticle antisera and complement, suggesting that immune
attack can also activite the heat shock system. The development of rapid microplate toxicity assays based on transgenic nematodes
is discussed. 相似文献
106.
107.
Background
Childhood maltreatment including abuse and neglect has been associated with adult obesity, but evidence on life-course development of obesity or BMI gain is unclear. We aim to establish whether childhood maltreatments are related to obesity or BMI at different life-stages 7y-50y and to identify possible explanations for associations.Methods
Childhood physical, psychological and sexual abuse, neglect and BMI at seven ages were recorded in the 1958 birth cohort (n~15,000). Associations of child maltreatments with BMI at separate ages were tested using linear regression or logistic regression for obesity, and with rate of child-to-adult BMI gain using multilevel models. We adjusted for potential covariates.Results
Abuse was reported in ~12% of the population. Abuse was not associated with elevated childhood BMI, but adult associations were observed: i.e. the abused had faster child-adult BMI gain than the non-abused; associations were independent of adult covariates. For physical abuse in both genders there was a positive linear association of ~0.006/y zBMI gain with age after adjustment for all covariates. Similarly, there was a linear association of physical abuse with obesity risk: e.g. among females from a low ORadjusted of 0.34 (0.16,0.71) at 7y to 1.67 (1.25,2.24) at 50y. In females faster zBMI gains with age of ~0.0034/y were observed for sexual abuse and increases in obesity risk were faster: from a low ORadjusted of 0.23 (0.06,0.84) at 7y to 1.34 (0.86,2.10) at 50y. Psychological abuse and neglect associations were less consistent.Conclusions
Childhood maltreatment associations with BMI or obesity varied across life: physical and, in females, sexual abuse were associated with faster lifetime BMI gains, which may have detrimental long-term health consequences. 相似文献108.
Daniel Houle Alain Paquette Beno?t C?té Travis Logan Hugues Power Isabelle Charron Louis Duchesne 《PloS one》2015,10(12)
Maple syrup production is an important economic activity in north-eastern North-America. The beginning and length of the production season is linked to daily variation in temperature. There are increasing concerns about the potential impact of climatic change on this industry. Here, we used weekly data of syrup yield for the 1999–2011 period from 121 maple stands in 11 regions of Québec (Canada) to predict how the period of production may be impacted by climate warming. The date at which the production begins is highly variable between years with an average range of 36 days among the regions. However, the average start date for a given region, which ranged from Julian day 65 to 83, was highly predictable (r2 = 0.88) using the average temperature from January to April (TJ-A). A logistic model predicting the weekly presence or absence of production was also developed. Using the inputs of 77 future climate scenarios issued from global models, projections of future production timing were made based on average TJ-A and on the logistic model. The projections of both approaches were in very good agreement and suggest that the sap season will be displaced to occur 15–19 days earlier on average in the 2080–2100 period. The data also show that the displacement in time will not be accompanied by a greater between years variability in the beginning of the season. However, in the southern part of Québec, very short periods of syrup production due to unfavourable conditions in the spring will occur more frequently in the future although their absolute frequencies will remain low. 相似文献
109.
Antony JM Ellestad KK Hammond R Imaizumi K Mallet F Warren KG Power C 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(2):1210-1224
Retroviral envelopes are pathogenic glycoproteins which cause neuroinflammation, neurodegeneration, and endoplasmic reticulum stress responses. The human endogenous retrovirus (HERV-W) envelope protein, Syncytin-1, is highly expressed in CNS glia of individuals with multiple sclerosis (MS). In this study, we investigated the mechanisms by which Syncytin-1 mediated neuroimmune activation and oligodendrocytes damage. In brain tissue from individuals with MS, ASCT1, a receptor for Syncytin-1 and a neutral amino acid transporter, was selectively suppressed in astrocytes (p < 0.05). Syncytin-1 induced the expression of the endoplasmic reticulum stress sensor, old astrocyte specifically induced substance (OASIS), in cultured astrocytes, similar to findings in MS brains. Overexpression of OASIS in astrocytes increased inducible NO synthase expression but concurrently down-regulated ASCT1 (p < 0.01). Treatment of astrocytes with a NO donor enhanced expression of early growth response 1, with an ensuing reduction in ASCT1 expression (p < 0.05). Small-interfering RNA molecules targeting Syncytin-1 selectively down-regulated its expression, preventing the suppression of ASCT1 and the release of oligodendrocyte cytotoxins by astrocytes. A Syncytin-1-transgenic mouse expressing Syncytin-1 under the glial fibrillary acidic protein promoter demonstrated neuroinflammation, ASCT1 suppression, and diminished levels of myelin proteins in the corpus callosum, consistent with observations in CNS tissues from MS patients together with neurobehavioral abnormalities compared with wild-type littermates (p < 0.05). Thus, Syncytin-1 initiated an OASIS-mediated suppression of ASCT1 in astrocytes through the induction of inducible NO synthase with ensuing oligodendrocyte injury. These studies provide new insights into the role of HERV-mediated neuroinflammation and its contribution to an autoimmune disease. 相似文献
110.
Power MR Li B Yamamoto M Akira S Lin TJ 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(5):3170-3176
Toll-IL-1R domain-containing adaptor-inducing IFN-beta (TRIF) is an adaptor molecule that mediates a distinct TLR signaling pathway. Roles of TRIF in the host defense have been primarily associated with virus infections owing to the induction of IFN-alphabeta. In this study, we investigated a role of TRIF in Pseudomonas aeruginosa infection. In vitro, TRIF-deficient mouse alveolar and peritoneal macrophages showed a complete inhibition of RANTES (CCL5) production, severely impaired TNF and KC (CXCL1) production, and reduced NF-kappaB activation in response to P. aeruginosa stimulation. In vivo, TRIF-deficient mice showed a complete inhibition of RANTES production, a severely impaired TNF and KC production, and an efficient MIP-2 and IL-1beta production in the lung following P. aeruginosa infection. This outcome was associated with a delayed recruitment of neutrophils into the airways. These results suggest that TRIF mediates a distinct cytokine/chemokine profile in response to P. aeruginosa infection. P. aeruginosa-induced RANTES production is completely dependent on TRIF pathway in mice. Importantly, TRIF deficiency leads to impaired clearance of P. aeruginosa from the lung during the initial 24-48 h of infection. Thus, TRIF represents a novel mechanism involved in the development of host response to P. aeruginosa infection. 相似文献