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41.
Debra?L.?Abercrombie Shelley?C.?Clarke Mahmood?S.?ShivjiEmail author 《Conservation Genetics》2005,6(5):775-788
The future status of sharks is an issue of widespread conservation concern due to declines in many species in the face of
high levels of exploitation to satisfy market demands for products, especially fins. Substantial declines in the large-bodied
hammerhead sharks, Sphyrna lewini, S. mokarran and S. zygaena, even in regions where some management occurs, indicate that informed conservation measures are warranted for these circumglobally
distributed species. Despite the importance of assessing shark catch and trade on a species-specific basis to detect potential
overexploitation of individual species, achieving this goal for hammerheads has proven elusive due to difficulties in identification
of their products. Here, we present the development and application of a diagnostic, streamlined, five-primer multiplex polymerase
chain reaction assay utilizing species-specific primers based on nuclear ribosomal ITS2 for the three hammerhead species throughout
their global distribution. Application of this assay to investigations of the fin market confirmed the presence of hammerhead
fins in the international trade. A study of the world’s largest fin market in Hong Kong revealed a high concordance between
specific Chinese-name trade categories and fins from these three species (“Bai Chun” with S. lewini, “Gui Chun” with S. zygaena and “Gu Pian” with S.␣mokarran), and clear species preferences. This concordance information allows the use of market records for monitoring species-specific
trends in trade and exploitation rates. The assay is also proving useful for identification of shark body parts in U.S. fisheries
law-enforcement activities. Screening of morphologically identified “ S. lewini” from globally distributed areas using this assay with subsequent whole ITS2 sequencing suggests a cryptic species closely
related to S. lewini occurs off the SE USA coast. 相似文献
42.
Mattson BJ Bossert JM Simmons DE Nozaki N Nagarkar D Kreuter JD Hope BT 《Journal of neurochemistry》2005,95(5):1481-1494
43.
Only a few novel classes of antiparasitic drugs have emerged over the last few decades, reflecting the difficulties associated with bringing a safe, effective molecule to market. In recent years, the screening paradigm has shifted from empirical whole parasite screening towards mechanism-based high throughput screening. This approach requires investment in molecular parasitology and in understanding the basic biology of parasites, as well as requiring considerable investment in an infrastructure for screening. Add to this the fact that the drug discovery process is iterative with high attrition, the Animal Health industry by necessity must focus on discovering medicines for diseases, which will deliver a return on investment. In recent years the rapid progression of genomics has unlocked a plethora of tools for target identification, validation and screening, revolutionising mechanism-based screening for antiparasitic drug discovery. The challenge still remains; however, to identify novel chemical entities with the properties required to deliver a safe, effective antiparasitic drug. 相似文献
44.
Krueger AC Madigan DL Green BE Hutchinson DK Jiang WW Kati WM Liu Y Maring CJ Masse SV McDaniel KF Middleton TR Mo H Molla A Montgomery DA Ng TI Kempf DJ 《Bioorganic & medicinal chemistry letters》2007,17(8):2289-2292
Substituted 1-hydroxy-4,4-dialkyl-3-oxo-3,4-dihydronaphthalene benzothiadiazine derivatives were investigated as inhibitors of genotype 1 HCV polymerase. Structure-activity relationship patterns for this class of compounds are discussed. It was found that the saturated alkane dialkyl units provided the most active analogs. 相似文献
45.
Debra J. Taxman Karen V. Swanson Peter M. Broglie Haitao Wen Elizabeth Holley-Guthrie Max Tze-Han Huang Justin B. Callaway Tim K. Eitas Joseph A. Duncan Jenny P. Y. Ting 《The Journal of biological chemistry》2012,287(39):32791-32799
The interleukin (IL)-1β-processing inflammasome has recently been identified as a target for pathogenic evasion of the inflammatory response by a number of bacteria and viruses. We postulated that the periodontal pathogen, Porphyromonas gingivalis may suppress the inflammasome as a mechanism for its low immunogenicity and pathogenic synergy with other, more highly immunogenic periodontal bacteria. Our results show that P. gingivalis lacks signaling capability for the activation of the inflammasome in mouse macrophages. Furthermore, P. gingivalis can suppress inflammasome activation by another periodontal bacterium, Fusobacterium nucleatum. This repression affects IL-1β processing, as well as other inflammasome-mediated processes, including IL-18 processing and cell death, in both human and mouse macrophages. F. nucleatum activates IL-1β processing through the Nlrp3 inflammasome; however, P. gingivalis repression is not mediated through reduced levels of inflammasome components. P. gingivalis can repress Nlrp3 inflammasome activation by Escherichia coli, and by danger-associated molecular patterns and pattern-associated molecular patterns that mediate activation through endocytosis. However, P. gingivalis does not suppress Nlrp3 inflammasome activation by ATP or nigericin. This suggests that P. gingivalis may preferentially suppress endocytic pathways toward inflammasome activation. To directly test whether P. gingivalis infection affects endocytosis, we assessed the uptake of fluorescent particles in the presence or absence of P. gingivalis. Our results show that P. gingivalis limits both the number of cells taking up beads and the number of beads taken up for bead-positive cells. These results provide a novel mechanism of pathogen-mediated inflammasome inhibition through the suppression of endocytosis. 相似文献
46.
In this study, three major hemocyte types were identified in the Sydney rock oyster. They were characterized primarily by light and electron microscopy based on the presence or absence of granules and nucleus to cytoplasm ratios. Hemoblast-like cells were the smallest cell type 4.0+/-0.4microm and comprised 15+/-3% of the hemocyte population. They had large nuclei and scanty basic cytoplasm. This cell type also had some endoplasmic reticuli and mitochondria. The second major type were hyalinocytes. Hyalinocytes represented 46+/-6% of all hemocytes. They were large cells (7.1+/-1.0microm) that had low nucleus:cytoplasm ratios and agranular basic or acidic cytoplasm. Hyalinocytes had the ability to phagocytose yeast cells and formed the core of hemocyte aggregates associated with agglutination. Four discrete sub-populations of hyalinocytes were identified. The third major cell type were the granulocytes, comprising 38+/-1% of the hemocyte population. These cells were large (9.3+/-0.3microm) and were characterized by cytoplasm containing many acidic or basic granules. Granulocytes were more phagocytic than hyalinocytes and they formed the inner layer of hemocytes during the encapsulation of fungal hyphae. Five discrete sub-populations of granulocytes were identified based on the types of granules in their cytoplasm. Flow cytometry showed that the hemocytes of rock oysters could be divided into between two and four major cell types based on their light scattering properties. The most common of the cell types identified by flow cytometry corresponded to hyalinocytes and granulocytes. Cytochemical assays showed that most enzymes associated with immunological activity were localized in granulocytes. Their granules contained acid phosphatase, peroxidase, phenoloxidase, superoxide and melanin. Hyalinocytes were positive only for acid phosphatase. All of these observations suggest that Sydney rock oysters have a broad variety of functionally specialized hemocytes, many of which are involved in host defense. 相似文献
47.
Giraud GD Faber JJ Jonker SS Davis L Anderson DF 《American journal of physiology. Heart and circulatory physiology》2006,291(6):H2884-H2888
Six singleton fetal sheep of 118-122 days gestational age were instrumented with flow sensors on the brachiocephalic artery, the postductal aorta, and the common umbilical artery and with arterial and venous intravascular catheters. At 125-131 days of gestation, we started week-long continuous recordings of flows and pressures. After control measures had been obtained, the fetuses were given continuous intravenous infusions of adult sheep plasma at an initial rate of 229 ml/day. After 1 wk of infusion, fetal plasma protein concentrations had increased from 34 to 78 g/l, arterial and venous pressures had increased from 42 to 64 and from 2.7 to 3.7 mmHg, and systemic resistance (exclusive of the coronary bed) had increased from 0.047 to 0.075 mmHg.min(-1).ml(-1), whereas placental resistance had increased from 0.065 to 0.111 mmHg.min(-1).ml(-1). Fetal plasma renin activities fell as early as 1 day after the start of infusion and remained below control (all changes P < 0.05). All flows decreased slightly although these decreases were not statistically significant. Thus the increase in arterial pressure was entirely due to an increase in systemic and placental resistances. 相似文献
48.
49.
Marcel Westenberg Sophie Bamps Helen Soedling Ian A Hope Colin T Dolphin 《BMC biotechnology》2010,10(1):27
Background
Escherichia coli strain EL350 contains chromosomally integrated phage lambda Red recombinase genes enabling this strain to be used for modifying the sequence of resident clones via recombineering. BAC and fosmid clones are highly suitable for modification by recombineering but, because they are present at low (1-2) copies per cell, the DNA is difficult to isolate in high yield and purity. To overcome this limitation vectors, e.g. pCC1FOS, have been constructed that contain the additional replication origin, oriV, which permits copy-number to be induced transiently when propagated in a suitable host strain, e.g. EPI300, that supplies the cognate trans -replication protein TrfA. Previously, we used EL350 and EPI300 sequentially to recombineer oriV -equipped fosmid genomic clones and, subsequently, to induce copy-number of the resulting recombinant clone. To eliminate these intervening DNA isolation and transformation steps we retrofitted EL350 with a P BAD-driven trfA gene generating strain MW005 that supports, independently, both recombineering and copy-number induction. 相似文献50.
Courtney L. Jones Teena Bhatla Roy Blum Jinhua Wang Steven W. Paugh Xin Wen Wallace Bourgeois Danielle S. Bitterman Elizabeth A. Raetz Debra J. Morrison David T. Teachey William E. Evans Michael J. Garabedian William L. Carroll 《The Journal of biological chemistry》2014,289(30):20502-20515
Although great advances have been made in the treatment of pediatric acute lymphoblastic leukemia, up to one of five patients will relapse, and their prognosis thereafter is dismal. We have previously identified recurrent deletions in TBL1XR1, which encodes for an F-box like protein responsible for regulating the nuclear hormone repressor complex stability. Here we model TBL1XR1 deletions in B-precursor ALL cell lines and show that TBL1XR1 knockdown results in reduced glucocorticoid receptor recruitment to glucocorticoid responsive genes and ultimately decreased glucocorticoid signaling caused by increased levels of nuclear hormone repressor 1 and HDAC3. Reduction in glucocorticoid signaling in TBL1XR1-depleted lines resulted in resistance to glucocorticoid agonists, but not to other chemotherapeutic agents. Importantly, we show that treatment with the HDAC inhibitor SAHA restores sensitivity to prednisolone in TBL1XR1-depleted cells. Altogether, our data indicate that loss of TBL1XR1 is a novel driver of glucocorticoid resistance in ALL and that epigenetic therapy may have future application in restoring drug sensitivity at relapse. 相似文献