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51.
Stolina M Bolon B Middleton S Dwyer D Brown H Duryea D Zhu L Rohner A Pretorius J Kostenuik P Feige U Zack D 《Journal of clinical immunology》2009,29(2):158-174
Introduction Rats with adjuvant-induced arthritis (AIA) were necropsied on 14 occasions during preclinical, acute clinical and chronic
clinical stages of AIA progression to characterize local (joint protein extracts) and systemic (serum) levels of mediators
regulating inflammation and bone erosion in conjunction with lymphoid tissue-specific leukocyte kinetics.
Results Systemic increases in alpha1 acid glycoprotein, tumor necrosis factor-α (TNFα), interleukin (IL)-17, transforming growth factor
beta (TGFβ), and chemokine (C–C motif) ligand 2 (CCL2) together with local IL-1α/β and TGFβ enrichment and local lymphoid
hyperplasia preceded the onset of clinical disease and joint damage. Systemic upregulation of TNFα, IL-6, IL-17, TGFβ, IL-18,
CCL2, receptor activator of nuclear factor-κβ ligand (RANKL), and prostaglandin E2 during acute and/or chronic AIA coincided with systemic leukocytosis and CD4+ T cell increase in blood and spleen. In contrast,
progression of joint erosions during clinical AIA was associated with intra-articular increases in IL-1α/β, IL-6, RANKL, IL-17,
TGFβ, CCL2, and KC/GRO and also a dramatic decline in osteoprotegerin.
Conclusion These data indicate that systemic and local events in inflammatory arthritis are discrete processes, driven by multiple cellular
and humoral mediators with distinct kinetic profiles. 相似文献
52.
Sarah L. Noton Vanessa M. Cowton Chadene R. Zack David R. McGivern Rachel Fearns 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(22):10226-10231
RNA virus polymerases must initiate replicative RNA synthesis with extremely high accuracy to maintain their genome termini and to avoid generating defective genomes. For the single-stranded negative-sense RNA viruses, it is not known how this accuracy is achieved. To investigate this question, mutations were introduced into the 3′ terminal base of a respiratory syncytial virus (RSV) template, and the RNA products were examined to determine the impact of the mutation. To perform the assay, RNA replication was reconstituted using a modified minireplicon system in which replication was limited to a single step. Importantly, this system allowed analysis of RSV RNA generated intracellularly, but from a defined template that was not subject to selection by replication. Sequence analysis of RNA products generated from templates containing 1U-C and 1U-A substitutions showed that, in both cases, replication products were initiated with a nontemplated, WT A residue, rather than a templated G or U residue, indicating that the polymerase selects the terminal NTP independently of the template. Examination of a template in which the position 1 nucleotide was deleted supported these findings. This mutant directed efficient replication at ∼60% of WT levels, and its product was found to be initiated at the WT position (−1 relative to the template) with a WT A residue. These findings show that the RSV replicase selects ATP and initiates at the correct position, independently of the first nucleotide of the template, suggesting a mechanism by which highly accurate replication initiation is achieved. 相似文献
53.
This study assessed incidental recognition of Alcohol and Neutral words in adolescents who encoded the words under distraction. Participants were 171 (87 male) 10th grade students, ages 14–16 (M = 15.1) years. Testing was conducted by telephone: Participants listened to a list containing Alcohol and Neutral (Experimental — Group E, n = 92) or only Neutral (Control — Group C, n = 79) words, while counting backwards from 200 by two's. Recognition was tested immediately thereafter. Group C exhibited higher false recognition of Neutral than Alcohol items, whereas Group E displayed equivalent false rates for both word types. The reported number of alcohol TV ads seen in the past week predicted higher false recognition of Neutral words in Group C and of Alcohol words in Group E. False memory for Alcohol words in Group E was greater in males and high anxiety sensitive participants. These context-dependent biases may contribute to exaggerations in perceived drinking norms previously found to predict alcohol misuse in young drinkers. 相似文献
54.
Tong Chen Hao Bai Ying Shao Melanie Arzigian Viktor Janzen Eyal Attar Yi Xie David T Scadden Zack Z Wang 《Stem cells (Dayton, Ohio)》2007,25(2):392-401
The molecular mechanisms that regulate human blood vessel formation during early development are largely unknown. Here we used human ESCs (hESCs) as an in vitro model to explore early human vasculogenesis. We demonstrated that stromal cell-derived factor-1 (SDF-1) and CXCR4 were expressed concurrently with hESC-derived embryonic endothelial differentiation. Human ESC-derived embryonic endothelial cells underwent dose-dependent chemotaxis to SDF-1, which enhanced vascular network formation in Matrigel. Blocking of CXCR4 signaling abolished capillary-like structures induced by SDF-1. Inhibition of the SDF-1/CXCR4 signaling pathway by AMD3100, a CXCR4 antagonist, disrupted the endothelial sprouting outgrowth from human embryoid bodies, suggesting that the SDF-1/CXCR4 axis plays a critical role in regulating initial vessel formation, and may function as a morphogen during human embryonic vascular development. 相似文献
55.
F. Zack H. Schau A. Dalchow M. Rock V. Blaas Andreas Bttner 《International journal of legal medicine》2020,134(4):1353-1359
Exposure to high-voltage electric arcs as a result of an accident or by means to commit suicide can affect people’s health and cause death. There are characteristic external findings that can be found on external examination. These include extensive skin burns, periorbital recesses or “crow’s feet,” vapor deposition of conductor material, known as metallization, and tightly spaced, roundish, crocodile skin like burns. The Institute of Legal Medicine of the Rostock University Medical Center recorded 16 deaths caused by exposure to electricity between 1990 and 2018. Six of these deaths were caused by exposure to high-voltage electric arcs and five of these deaths (83 %) showed crocodile skin like burns and one had periorbital recesses burns on the face as a result of a fault arc. To our knowledge, the present paper is the first report describing the frequent occurrence of crocodile skin like burns due to high-voltage fault arcs. 相似文献
56.
Retrograde axonal transport of BDNF in retinal ganglion cells is blocked by acute IOP elevation in rats 总被引:31,自引:0,他引:31
Quigley HA McKinnon SJ Zack DJ Pease ME Kerrigan-Baumrind LA Kerrigan DF Mitchell RS 《Investigative ophthalmology & visual science》2000,41(11):3460-3466
PURPOSE: To determine whether acute experimental glaucoma in rats obstructs retrograde transport of brain-derived neurotrophic factor (BDNF) to retinal ganglion cells (RGCs). METHODS: Forty rats had unilateral injection of either (125)I-BDNF (20 animals) or a mixture of (125)I-BDNF and 100-fold excess nonradiolabeled BDNF (20 animals). In each group of 20 animals, eyes contralateral to injection had either normal intraocular pressure (IOP; 10 animals) or IOP elevated to 25 mm Hg below the systolic blood pressure of the eye (10 animals). In each group of 20 rats, ipsilateral eyes had IOP set at systolic blood pressure (4 eyes), had optic nerve transection (10 eyes), or had normal IOP (6 eyes). Six hours after injection, animals were killed and tissues were fixed, embedded, and sectioned for autoradiography. Grain counts were performed over retina and optic nerve using automated image analysis. RESULTS: IOP elevation to 25 mm Hg below systolic blood pressure (perfusion pressure [PP] 25) decreased median retinal nerve fiber layer (NFL) grains by 38% compared with controls (P: < 0.001). Competition by cold BDNF reduced NFL grains by 28% (P: = 0.013). Considering only the radioactivity representing specific retrograde transport of BDNF, IOP elevation to PP25 reduced transport by 74%, whereas elevation to PP0 (equaling systolic blood pressure) reduced specific transport by 83%. CONCLUSIONS: BDNF is transported retrogradely from the superior colliculus in adult rats, and this transport is substantially inhibited by acute IOP elevation. Deprivation of BDNF among RGCs may contribute to neuron loss in glaucoma. 相似文献
57.
58.
F W?rnberg J Bergh M Zack L Holmberg 《Cancer epidemiology, biomarkers & prevention》2001,10(5):495-499
In a case-control study derived from a cohort of 4661 women with a primary carcinoma in situ of the breast, we investigated age at diagnosis, mode of detection, tumor characteristics, and primary therapy, as prognostic factors for developing invasive breast cancer or dying from breast cancer. From all of the women with a primary carcinoma in situ reported to the Swedish Cancer Registry from 1960 through 1992, we selected as cases all of the women with a ductal carcinoma in situ who later died of breast cancer (n = 39) or who developed a subsequent invasive cancer in either breast (n = 118). From this cohort, we also selected controls matched to the cases by year of diagnosis and health care region. We conducted univariate and multivariate analyses to study the association between risk of invasive cancer or death and the different risk factors. Large size, diameter > or = 25 mm [odds ratio (OR), 3.5; 95% confidence interval (CI), 1.1-11.4] and multifocality (OR, 3.9; 95% CI, 1.2-12.7) increased the risk of breast cancer death in univariate analysis. Postoperative radiotherapy (OR, 0.1; 95% CI, 0.0-1.0) and mastectomy (OR, 0.1-95% CI, 0.0-0.5) lowered the risk of an ipsilateral invasive cancer in multivariate analysis. The risk pattern by treatment category differed between those who had an ipsilateral invasive cancer and those who either had a contralateral cancer or died from breast cancer. The driving forces behind local and generalized disease may differ. Because confounding by indication may influence the effects of different treatments, the results should be interpreted with caution. 相似文献
59.
Zack Papper Natalie M. Jameson Roberto Romero Amy L. Weckle Pooja Mittal Kurt Benirschke Joaquin Santolaya-Forgas Monica Uddin David Haig Morris Goodman Derek E. Wildman 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(40):17083-17088
In anthropoid primates, growth hormone (GH) genes have undergone at least 2 independent locus expansions, one in platyrrhines (New World monkeys) and another in catarrhines (Old World monkeys and apes). In catarrhines, the GH cluster has a pituitary-expressed gene called GH1; the remaining GH genes include placental GHs and placental lactogens. Here, we provide cDNA sequence evidence that the platyrrhine GH cluster also includes at least 3 placenta expressed genes and phylogenetic evidence that placenta expressed anthropoid GH genes have undergone strong adaptive evolution, whereas pituitary-expressed GH genes have faced strict functional constraint. Our phylogenetic evidence also points to lineage-specific gene gain and loss in early placental mammalian evolution, with at least three copies of the GH gene present at the time of the last common ancestor (LCA) of primates, rodents, and laurasiatherians. Anthropoid primates and laurasiatherians share gene descendants of one of these three copies, whereas rodents and strepsirrhine primates each maintain a separate copy. Eight of the amino-acid replacements that occurred on the lineage leading to the LCA of extant anthropoids have been implicated in GH signaling at the maternal-fetal interface. Thus, placental expression of GH may have preceded the separate series of GH gene duplications that occurred in catarrhines and platyrrhines (i.e., the roles played by placenta-expressed GHs in human pregnancy may have a longer evolutionary history than previously appreciated). 相似文献
60.
P Gouras J Du H Kjeldbye R Kwun R Lopez D J Zack 《Investigative ophthalmology & visual science》1991,32(13):3167-3174
Dissociated photoreceptor cells from a transgenic strain of mice, containing a bovine promoter lac Z gene construct, were transplanted to the dystrophic retinas of a strain of mice (C3H, rd/rd) without obvious photoreceptors. The transgenic photoreceptor cells expressed beta-galactosidase and were distinguishable from the host retinal cells by light and electron microscopy after the 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside histochemical reaction. These results showed that transplanted transgenic photoreceptor cells survived at least 1 month in the host retina and had a primitive outer segment and a well-developed synaptic terminal. 相似文献