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排序方式: 共有446条查询结果,搜索用时 15 毫秒
1.
Lawrence K. Duffy Michelle K. Hecker Gail M. Blundell R. Terry Bowyer 《Polar Biology》1999,21(1):56-58
Approximately 8 years after the Exxon Valdez oil spill, river otters (Lutra canadensis) were trapped from the shoreline in both oiled (Knight Island) and nonoiled (Jackpot Bay) areas of Prince William Sound,
Alaska. Captive river otters were wiped with isopropanol-soaked gauze and the gauze extracts were analyzed by gas chromatography
with mass spectrometry detection. Differences in pentacosane (C-25) levels in the fur were observed between the oiled and
nonoiled sites, while lower molecular weight aliphatics and aromatics were absent. These data are useful when evaluating the
role of fur grooming in the long-term exposure of river otters to hydrocarbons and the expression of P450-1A in Knight Island
otters.
Accepted: 26 August 1998 相似文献
2.
The acyclic CB1R inverse agonist taranabant mediates weight loss by increasing energy expenditure and decreasing caloric intake 总被引:6,自引:0,他引:6
Addy C Wright H Van Laere K Gantz I Erondu N Musser BJ Lu K Yuan J Sanabria-Bohórquez SM Stoch A Stevens C Fong TM De Lepeleire I Cilissen C Cote J Rosko K Gendrano IN Nguyen AM Gumbiner B Rothenberg P de Hoon J Bormans G Depré M Eng WS Ravussin E Klein S Blundell J Herman GA Burns HD Hargreaves RJ Wagner J Gottesdiener K Amatruda JM Heymsfield SB 《Cell metabolism》2008,7(1):68-78
Cannabinoid 1 receptor (CB1R) inverse agonists are emerging as a potential obesity therapy. However, the physiological mechanisms by which these agents modulate human energy balance are incompletely elucidated. Here, we describe a comprehensive clinical research study of taranabant, a structurally novel acyclic CB1R inverse agonist. Positron emission tomography imaging using the selective CB1R tracer [(18)F]MK-9470 confirmed central nervous system receptor occupancy levels ( approximately 10%-40%) associated with energy balance/weight-loss effects in animals. In a 12-week weight-loss study, taranabant induced statistically significant weight loss compared to placebo in obese subjects over the entire range of evaluated doses (0.5, 2, 4, and 6 mg once per day) (p < 0.001). Taranabant treatment was associated with dose-related increased incidence of clinical adverse events, including mild to moderate gastrointestinal and psychiatric effects. Mechanism-of-action studies suggest that engagement of the CB1R by taranabant leads to weight loss by reducing food intake and increasing energy expenditure and fat oxidation. 相似文献
3.
Martha Luevano Anna Domogala Michael Blundell Nicola Jackson Isabela Pedroza-Pacheco Sophie Derniame Michelle Escobedo-Cousin Sergio Querol Adrian Thrasher Alejandro Madrigal Aurore Saudemont 《PloS one》2014,9(1)
Adoptive natural killer (NK) cell therapy relies on the acquisition of large numbers of NK cells that are cytotoxic but not exhausted. NK cell differentiation from hematopoietic stem cells (HSC) has become an alluring option for NK cell therapy, with umbilical cord blood (UCB) and mobilized peripheral blood (PBCD34+) being the most accessible HSC sources as collection procedures are less invasive. In this study we compared the capacity of frozen or freshly isolated UCB hematopoietic stem cells (CBCD34+) and frozen PBCD34+ to generate NK cells in vitro. By modifying a previously published protocol, we showed that frozen CBCD34+ cultures generated higher NK cell numbers without loss of function compared to fresh CBCD34+ cultures. NK cells generated from CBCD34+ and PBCD34+ expressed low levels of killer-cell immunoglobulin-like receptors but high levels of activating receptors and of the myeloid marker CD33. However, blocking studies showed that CD33 expression did not impact on the functions of the generated cells. CBCD34+-NK cells exhibited increased capacity to secrete IFN-γ and kill K562 in vitro and in vivo as compared to PBCD34+-NK cells. Moreover, K562 killing by the generated NK cells could be further enhanced by IL-12 stimulation. Our data indicate that the use of frozen CBCD34+ for the production of NK cells in vitro results in higher cell numbers than PBCD34+, without jeopardizing their functionality, rendering them suitable for NK cell immunotherapy. The results presented here provide an optimal strategy to generate NK cells in vitro for immunotherapy that exhibit enhanced effector function when compared to alternate sources of HSC. 相似文献
4.
Pieter Stolk Harald E Heemstra Hubert GM Leufkens Brigitte Bloechl-Daum Eibert R Heerdink 《Orphanet journal of rare diseases》2009,4(1):1-7
Background
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease, which rapidly leads to chronic respiratory failure requiring mechanical ventilation. Currently, forced vital capacity (FVC) < 50% is considered as physiologic marker for admitting patients to Noninvasive Positive Pressure Ventilation (NPPV) intervention, although it has been recently shown the median survival of patients with baseline FVC < 75% much shorter than median survival of patients with baseline FVC > 75%, independently by any treatment.Aim
To assess the role of NPPV in improving outcome of ALS, a retrospective analysis was performed to investigate 1 year survival of ALS patients with FVC < 75% and nocturnal respiratory insufficiency, treated with NPPV, compared to a well-matched population of ALS patients, who refused or was intolerant to NPPV.Methods
We investigated seventy-two consecutive ALS patients who underwent pulmonary function test. Forty-four presented a FVC > 75% and served as control group. Twenty-eight patients presented a FVC < 75% and showed, at polysomnography analysis, nocturnal respiratory insufficiency, requiring NPPV; sixteen were treated with NPPV, while twelve refused or were intolerant.Results
Increased survival rate at 1 year in patients with FVC < 75% treated with NPPV, as compared to those who refused or could not tolerate NPPV (p = 0.02), was observed. The median rate of decline in FVC% was slower in NPPV patients than in patients who did not use NPPV (95% CI: 0.72 to 1.85; p < 0.0001).Conclusion
This report demonstrates that early treatment with NPPV prolongs survival and reduces decline of FVC% in ALS. 相似文献5.
6.
Brewerton SC Doré AS Drake AC Leuther KK Blundell TL 《Journal of structural biology》2004,145(3):295-306
DNA-dependent protein kinase (DNA-PK) is part of the eukaryotic DNA double strand break repair pathway and as such is crucial for maintenance of genomic stability, as well as for V(D)J (variable-diversity-joining) recombination. The catalytic subunit of DNA-PK (DNA-PKcs) belongs to the phosphatidylinositol-3 (PI-3) kinase-like kinase (PIKK) superfamily and is comprised of approximately 4100 amino acids. We have used a novel repeat detection method to analyse this enormous protein and have identified two different types of helical repeat motifs in the N-terminal region of the sequence, as well as other previously unreported features in this repeat region. A comparison with the ATMs, ATRs, and TORs show that the features identified are likely to be conserved throughout the PIKK superfamily. Homology modelling of parts of the DNA-PKcs sequence has been undertaken and we have been able to fit the models to previously obtained electron microscopy data. This work provides an insight into the overall architecture of the DNA-PKcs protein and identifies regions of interest for further experimental studies. 相似文献
7.
Surface interactions of gamma-crystallins in the crystal medium in relation to their association in the eye lens 总被引:3,自引:0,他引:3
Y V Sergeev Y N Chirgadze S E Mylvaganam H Driessen C Slingsby T L Blundell 《Proteins》1988,4(2):137-147
A comparative study of intermolecular interactions in crystals of two homologous low molecular weight proteins, gamma-II and gamma-IIIb crystallins, from calf eye lens was carried out. Crystal packings for these proteins are very different: intermolecular contact areas compose about 33% of the total accessible surface area of gamma-II as compared with 13% in gamma-III. Two key residues seem to be mainly responsible for the differences in protein association in the crystal medium. These are Ser 103 and Leu 155 in gamma-II, which are replaced by Met 103 and His 155 in gamma-IIb. A similar substitution of these residues is observed in different gene products of gamma-crystallins from a number of vertebrates. This is consistent with the existence of a genetically controlled mechanism for determining intermolecular association of gamma-crystallins in the native medium of the lens. 相似文献
8.
Meltzer PC Blundell P Chen Z Yong YF Madras BK 《Bioorganic & medicinal chemistry letters》1999,9(6):857-862
Herein we report the synthesis of a series of bicyclo[3.2.1]octanes and their binding characteristics at the dopamine and serotonin transporters. The data confirm that a heteroatom at position 8 of the tropane nucleus is not a prerequisite for binding since the bicyclo[3.2.1]octanes prove potent inhibitors of both transporters. Therefore the three-dimensional topology of the ligand may be more important than specific functionality with respect to stereospecific binding at the acceptor site. 相似文献
9.
10.
Milica D olovi GM Jankovi RB olovi Vesna M Martinovi-emeriki 《Cancer immunology, immunotherapy : CII》1998,15(4):286-288
A case of primary nonsecretory plasmacytoma of the spleen is reported. On laparotomy and splenectomy a 920 g spleen was removed,
measuring 16×14×6 cm. The cut surface of the entire spleen showed that the tumour occupied most of the splenic tissue. A bone
marrow aspirate and trephine, skeletal survey showed no signs of myeloma. Biopsy of the liver and regional lymph nodes was
normal. Immunocytochemistry of the splenic tumour showed positivity for pan-B and plasma cell markers. After splenectomy the
patient was treated with chemotherapy according to protocol VBCMP (M2). 相似文献