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61.
Traumatic brain injury (TBI) is associated with significant infectious and inflammatory complications. Though increasing evidence suggests that rFVIIa administration may be efficacious for the pre-hospital treatment of TBI, the FVIIa-tissue factor complex has been shown to be immunologically active. To date the cytokine response to rFVIIa administration for the treatment of TBI has not been evaluated. Twenty anesthetized immature Yorkshire swine underwent fluid percussion TBI. At 15 min following injury, animals were randomized to receive either 90 μg/kg rFVIIa (rFVIIa) or nothing. Animals were observed for 6 h and then euthanized. Plasma and cerebrospinal (CSF) samples were collected at 0 min and 360 min, and ELISA analysis of TNF-α, IL-1β and IL-10 was performed. Survival in both groups was 100%. Baseline cytokine concentrations were not statistically different between rFVIIa and control animals in plasma or CSF. Animals in both groups did not have significant changes in plasma cytokine concentrations following TBI. Control animals did not demonstrate significant changes from baseline of CSF cytokine concentrations following TBI. The administration of rFVIIa however, resulted in significant increases in CSF TNF-α concentration (232.0 pg/ml ± 75.9 vs 36.4 pg/ml ± 10.4, p = 0.036) and IL-10 concentration (10.7 pg/ml ± 0.6 vs 8.8 pg/ml ± 0.1, p = 0.015). IL-1β concentrations were not significantly changed over the experimental time course. These results suggest that rFVIIa administration for the treatment of TBI is not immunologically inert, and is associated with increased CSF concentrations of TNF-α and IL-10. 相似文献
62.
Whole‐field macro‐ and micro‐deformation characteristic of unbound water‐loss in dentin hard tissue 下载免费PDF全文
Zhenning Chen Bobby Nadeau Kevin Yu Xinxing Shao Xiaoyuan He M. Cynthia Goh Anil Kishen 《Journal of biophotonics》2018,11(9)
High‐resolution deformation measurements in a functionally graded hard tissue such as human dentin are essential to understand the unbound water‐loss mediated changes and their role in its mechanical integrity. Yet a whole‐field, 3‐dimensional (3D) measurement and characterization of fully hydrated dentin in both macro‐ and micro‐scales remain to be a challenge. This study was conducted in 2 stages. In stage‐1, a stereo‐digital image correlation approach was utilized to determine the water‐loss and load‐induced 3D deformations of teeth in a sagittal section over consecutively acquired frames, from a fully hydrated state to nonhydrated conditions for a period up to 2 hours. The macroscale analysis revealed concentrated residual deformations at the dentin‐enamel‐junction and the apical regions of root in the direction perpendicular to the dentinal tubules. Significant difference in the localized deformation characteristics was observed between the inner and outer aspects of the root dentin. During quasi‐static loadings, further increase in the residual deformation was observed in the dentin. In stage‐2, dentin microstructural variations induced by dynamic water‐loss were assessed with environmental scanning electron microscopy and atomic force microscopy (AFM), showing that the dynamic water‐loss induced distention of dentinal tubules with concave tubular edges, and concurrent contraction of intertubular dentin with convex profile. The findings from the current macro‐ and micro‐scale analysis provided insight on the free‐water‐loss induced regional deformations and ultrastructural changes in human dentin. 相似文献
63.
Molecular epidemiology of simian immunodeficiency virus SIVsm in U.S. primate centers unravels the origin of SIVmac and SIVstm 下载免费PDF全文
Apetrei C Kaur A Lerche NW Metzger M Pandrea I Hardcastle J Falkenstein S Bohm R Koehler J Traina-Dorge V Williams T Staprans S Plauche G Veazey RS McClure H Lackner AA Gormus B Robertson DL Marx PA 《Journal of virology》2005,79(14):8991-9005
Retrospective molecular epidemiology was performed on samples from four sooty mangabey (SM) colonies in the United States to characterize simian immunodeficiency virus SIVsm diversity in SMs and to trace virus circulation among different primate centers (PCs) over the past 30 years. The following SIVsm sequences were collected from different monkeys: 55 SIVsm isolates from the Tulane PC sampled between 1984 and 2004, 10 SIVsm isolates from the Yerkes PC sampled in 2002, 7 SIVsm isolates from the New Iberia PC sampled between 1979 and 1986, and 8 SIVsm isolates from the California PC sampled between 1975 and 1977. PCR and sequencing were done to characterize the gag, pol, and env gp36 genes. Phylogenetic analyses were correlated with the epidemiological data. Our analysis identified nine different divergent phylogenetic lineages that cocirculated in these four SM colonies in the Unites States in the past 30 years. Lineages 1 to 5 have been identified previously. Two of the newly identified SIVsm lineages found in SMs are ancestral to SIVmac251/SIVmac239/SIVmne and SIVstm. We further identified the origin of these two macaque viruses in SMs from the California National Primate Research Center. The diversity of SIVsm isolates in PCs in the United States mirrors that of human immunodeficiency virus type 1 (HIV-1) group M subtypes and offers a model for the molecular epidemiology of HIV and a new approach to vaccine testing. The cocirculation of divergent SIVsm strains in PCs resulted in founder effects, superinfections, and recombinations. This large array of SIVsm strains showing the same magnitude of diversity as HIV-1 group M subtypes should be extremely useful for modeling the efficacy of vaccination strategies under the real-world conditions of HIV-1 diversity. The genetic variability of SIVsm strains among PCs may influence the diagnosis and monitoring of SIVsm infection and, consequently, may bias the results of pathogenesis studies. 相似文献
64.
Nantermet PG Burgey CS Robinson KA Pellicore JM Newton CL Deng JZ Selnick HG Lewis SD Lucas BJ Krueger JA Miller-Stein C White RB Wong B McMasters DR Wallace AA Lynch JJ Yan Y Chen Z Kuo L Gardell SJ Shafer JA Vacca JP Lyle TA 《Bioorganic & medicinal chemistry letters》2005,15(11):2771-2775
In this study, we have demonstrated that the critical hydrogen bonding motif of the established 3-aminopyrazinone thrombin inhibitors can be effectively mimicked by a 2-aminopyridine N-oxide. As this peptidomimetic core is more resistant toward oxidative metabolism, it also overcomes the metabolic liability associated with the pyrazinones. An optimization study of the P(1) benzylamide delivered the potent thrombin inhibitor 21 (K(i) = 3.2 nM, 2xaPTT = 360 nM), which exhibited good plasma levels and half-life after oral dosing in the dog (C(max) = 2.6 microM, t(1/2) = 4.5 h). 相似文献
65.
A phylogeographical study of the Russian (Siberian) flying squirrel (Pteromys volans) was carried out using the complete mitochondrial (mt) cytochrome b gene sequences with special reference to the refugia theory for the arboreal traits of this species. We examined 31 specimens from 24 localities, resulting in 28 haplotypes. One breeding specimen with a unique haplotype from Hokkaido, Japan was included in the phylogenetic analysis. There were three mtDNA lineages: Hokkaido, Far Eastern, and northern Eurasia. Divergence data among lineages demonstrated that the Hokkaido group separated from the other groups during the Holsteinian interglacial. The phylogeographical pattern of P. volans is different from that previously reported for terrestrial rodents associated with treeless habitats. Unlike grasslands, forests decreased during glaciation and moved southward because of the cold and arid environmental conditions. The glacial refugia of P. volans would have been associated with forest dynamics in the Pleistocene. 相似文献
66.
The ability to use mixtures of deprotonated N-(3,5-dinitrobenzoyl)amino acids as chiral selectors for the determination of enantiomeric composition by electrospray ionization-mass spectrometry is demonstrated. For each experiment, two N-(3,5-dinitrobenzoyl)amino acids were chosen such that each would have opposite selectivity for the enantiomers of the analyte. Electrospray ionization-mass spectrometry, monitored in the negative ion mode, of solutions containing the two N-(3,5-dinitrobenzoyl)amino acids, sodium hydroxide, and the analyte, in a one-to-one mixture of methanol and water, afford peaks in the mass spectrum that correspond to the deprotonated 1:1 analyte-selector complexes. The ratio of the intensities of the complexes in the mass spectrum can be related to the enantiomeric composition of the analyte. Additionally, the sense and extent of chiral recognition is consistent with chromatographic observations, using chiral stationary phases derived from N-(3,5-dinitrobenzoyl)amino acids. Each analysis of enantiomeric composition requires less than 10 s to complete, indicating that this method has great potential for the development of fast-/high-throughput chiral analyses. 相似文献
67.
James?A.?Allen Ken?W.?KraussEmail author Katherine?C.?Ewel Bobby?D.?Keeland Erick?E.?Waguk 《Wetlands Ecology and Management》2005,13(6):657-669
Forested wetlands dominated by Terminalia carolinensis are endemic to Micronesia but common only on the island of Kosrae, Federated States of Micronesia. On Kosrae, these forests
occur on Nansepsep, Inkosr, and Sonahnpil soil types, which differ in degree of flooding and soil saturation. We compared
forest structure, growth, nutrition, and regeneration on two sites each on Nansepsep and Inkosr soils and one site on the
much less common Sonahnpil soil type. Terminalia tree sizes were similar on all three soil types, but forests differed in total basal area, species of smaller trees, and
total plant species diversity. Terminalia regeneration was found only on the Inkosr soil type, which had the highest water table levels. Other Terminalia species are relatively light demanding, and T. carolinensis exhibited similar characteristics. It is therefore likely that Terminalia requires periodic, but perhaps naturally rare, stand-replacing disturbances (e.g., typhoons) in order to maintain its dominance,
except on the wettest sites, where competition from other species is reduced. Terminalia swamps in the Nansepsep soil type appeared to be at the greatest risk of conversion to other uses, but swamps on all three
types may face greater pressure as Kosrae's population increases and the island's infrastructure becomes more developed. 相似文献
68.
William?R?Keye Bobby?Webster Richard?Dickey Stephen?Somkuti Jack?Crain M?Joseph?ScobeyEmail author 《Reproductive biology and endocrinology : RB&E》2005,3(1):62
Background
The safety and tolerability of a new highly purified, urine-derived human menopausal gonadotropin (hMG) preparation [Menopur(R)] was compared with a currently available hMG [Repronex (R)] in women undergoing in vitro fertilization (IVF). 相似文献69.
Direct inoculation of simian immunodeficiency virus from sooty mangabeys in black mangabeys (Lophocebus aterrimus): first evidence of AIDS in a heterologous African species and different pathologic outcomes of experimental infection 下载免费PDF全文
Apetrei C Gormus B Pandrea I Metzger M ten Haaft P Martin LN Bohm R Alvarez X Koopman G Murphey-Corb M Veazey RS Lackner AA Baskin G Heeney J Marx PA 《Journal of virology》2004,78(21):11506-11518
A unique opportunity for the study of the role of serial passage and cross-species transmission was offered by a series of experiments carried out at the Tulane National Primate Research Center in 1990. To develop an animal model for leprosy, three black mangabeys (BkMs) (Lophocebus aterrimus) were inoculated with lepromatous tissue that had been serially passaged in four sooty mangabeys (SMs) (Cercocebus atys). All three BkMs became infected with simian immunodeficiency virus from SMs (SIVsm) by day 30 postinoculation (p.i.) with lepromatous tissue. One (BkMG140) died 2 years p.i. from causes unrelated to SIV, one (BkMG139) survived for 10 years, whereas the third (BkMG138) was euthanized with AIDS after 5 years. Histopathology revealed a high number of giant cells in tissues from BkMG138, but no SIV-related lesions were found in the remaining two BkMs. Four-color immunofluorescence revealed high levels of SIVsm associated with both giant cells and T lymphocytes in BkMG138 and no detectable SIV in the remaining two. Serum viral load (VL) showed a significant increase (>1 log) during the late stage of the disease in BkMG138, as opposed to a continuous decline in VL in the remaining two BkMs. With the progression to AIDS, neopterin levels increased in BkMG138. This study took on new significance when phylogenetic analysis unexpectedly showed that all four serially inoculated SMs were infected with different SIVsm lineages prior to the beginning of the experiment. Furthermore, the strain infecting the BkMs originated from the last SM in the series. Therefore, the virus infecting BkMs has not been serially passaged. In conclusion, we present the first compelling evidence that direct cross-species transmission of SIV may induce AIDS in heterologous African nonhuman primate (NHP) species. The results showed that cross-species-transmitted SIVsm was well controlled in two of three BkMs for 2 and 10 years, respectively. Finally, this case of AIDS in an African monkey suggests that the dogma of SIV nonpathogenicity in African NHP hosts should be reconsidered. 相似文献
70.
Yanagawa Y Matsumoto M Togashi H 《Journal of immunology (Baltimore, Md. : 1950)》2010,185(10):5762-5768
Although noradrenaline (NA), a stress-associated neurotransmitter, seems to affect the immune system, the precise mechanisms underlying NA-mediated immunoregulation are not fully understood. We examined the effect of NA on Ag uptake (endocytosis) by dendritic cells (DCs) using murine bone marrow-derived DCs and fluorescence-labeled endocytic tracers (dextran and OVA). Ag uptake by DCs notably increased following a very brief treatment (3 min) with NA. NA-induced endocytosis was completely blocked by treatment with α(2)-adrenoceptor antagonist yohimbine. Neither α(1)-adrenoceptor antagonist prazosin nor β-adrenoceptor antagonist propranolol affected NA-induced endocytosis by DCs. A selective α(2)-adrenoceptor agonist, azepexole (B-HT 933), also significantly increased endocytosis by DCs. Thus, the α(2)-adrenoceptor seems to be responsible for NA-induced DC endocytosis. In parallel, NA markedly activated intracellular signaling pathways of PI3K and ERK1/2 in DCs. NA-mediated activation of these pathways was completely inhibited by yohimbine treatment. Blocking PI3K activation significantly reduced NA-induced endocytosis by DCs. Based on these results, NA rapidly enhances Ag capture by DCs via α(2) adrenoceptor-mediated PI3K activation, which may be associated with immune enhancement following acute stress. 相似文献