The production of cytokines by human conjunctival epithelial cells following stimulation was investigated. Primary cultures of human conjunctival epithelial cells were characterized by morphology and ...keratin expression. Cultured epithelial cells were treated with varying concentrations of lipopolysaccharide, interleukin (IL)-1β, calcium ionophore A23187' or phorbol myristate acetate, and cytokine secretion was determined over specified intervals. Culture supernatants and cell lysates were analyzed by ELISA for IL-1β, IL-3, IL-4, IL-5, IL-6, IL-8, IL-11, IL-1 receptor antagonist (IL-1ra), tumor necrosis factor-α (TNF-α), and granulocyte-macrophage colony stimulating factor (GM-CSF).
With the exception of IL-1ra, unstimulated conjunctival epithelial cells produced cytokines at relatively low or undetectable levels. IL-1ra was detected in both culture supernatants and cell lysates under basal conditions. In response to stimuli, conjunctival epithelial cells secreted the proinflammatory cytokines TNF-α, IL-6, IL-8, and GM-CSF in a dose-and time-dependent fashion. After stimulation, the intracellular levels of IL-1ra increased in these cells but the supernatant-associated levels remained unchanged. None of the other cytokines evaluated (IL-1β IL-3, IL-4, IL-5, and IL-11) were detected in supernatants or lysates of resting or stimulated cells.
These findings suggest that conjunctival epithelial cells may contribute to the pathogenesis of human ocular diseases by production of proinflammatory cytokines. Further evaluation of these cells as targets of therapy is warranted.
In this paper, we develop and evaluate models to estimate and optimize various performance metrics for unicast traffic using the hard scheduling (virtual circuit connection-oriented) mode of the ...reservation based protocol USAP in mobile ad-hoc wireless networks (MANETs). USAP (Unifying Slot Assignment Protocol) is a dynamic distributed resource allocation protocol for MANETs. We model USAP hard scheduling mode using loss network models along with reduced link capacity that couple physical, MAC and routing layers effects. The key effect of multiuser interference on a link is modeled via reduced link capacity where the effects of transmissions and receptions in the link neighborhood are modeled using USAP reservation rules. We compare our results with simulation and obtain good results using our loss network models but with reduced link capacity distribution obtained by simulation. We also compute the throughput sensitivities with respect to network parameters and use these sensitivities to improve network performance.
The effects of transcutaneous electrical nerve stimulation (TENS) on myofascial pain and trigger point sensitivity were assessed. Four modes of TENS and a no-stimulation control were compared in a ...double-blind design. Stimulation, carried out for 10 min on 60 subjects (12/group), showed significant pain reductions with 100 Hz, 250 msec stimulation followed by 100 Hz, 50 msec and then pain suppressor TENS. No pain reductions were found in the 2 Hz, 250 msec TENS or the control. No significant alteration in myofascial trigger point sensitivity, assessed with the pressure algometer, was found between the groups. The results suggest that high frequency, high intensity TENS is effective in reducing myofascial pain, and that these pain reductions do not reflect changes in local trigger point sensitivity.
The Heroin Addicts' View of Methadone Maintenance Ball, John C.; Graff, Harold; Sheehan Jr, John J.
British Journal of Addiction to Alcohol & Other Drugs,
March 1974, Letnik:
69, Številka:
1
Journal Article
Memory for the intensity of past physical pain depends critically on the intensity of present pain. When their present pain intensity was high, patients with chronic headaches of myofascial origin ...rated their maximum, usual, and minimum levels of prior pain as being more severe than their hourly pain diaries indicated. When their present pain intensity was low, the same patients remembered all 3 levels of prior pain as being less severe than they actually had been. The results show that pain produces systematic distortions of memory similar to those associated with alterations of affect or mood, and suggest a resolution to a conspicuous conflict in the current pain literature.
Previously described models of endotoxin-induced uveitis quantify neutrophil influx into the eye using biochemical or direct cell count methods that result in an underestimation of ocular leukocyte ...accumulation following the inflammatory stimulus. We have optimized the rat model of endotoxin-induced uveitis by first overcoming interference in the biochemical assay of myeloperoxidase due to endogenous ocular reductants and cellular constituents containing free thiol functional groups. This was accomplished by simultaneously 1) extensively diluting soluble, interfering substances and 2) blocking tissue sulfhydril functional groups during tissue homogenization. Uveitis was induced in rats by subplantar injection of endotoxin. Twenty-four hours later, eyes were enucleated, homogenized, fractionated, and myeloperoxidase activity of neutrophils sedimenting with the membranous pellet was extracted. Previously published extraction procedures yielded only 40% of total assayable myeloperoxidase activity. Optimal recovery of myeloperoxidase activity (>twofold increase) was achieved only with two sequential extractions using 50 mM phosphate buffer (pH 7.4) containing 10 mM
N-ethylmaleimide, and subsequent solubilization of myeloperoxidase activity by extraction with 0.5% hexadecyltrimethylammonium bromide in 50 mM phosphate buffer (pH 6.0). This modified extraction procedure and optimized myeloperoxidase assay conditions (300 μM hydrogen peroxide and 1.5 mM o-dianisidine) were then used to enhance the uveitis model. Maximum ocular neutrophil accumulation was observed at endotoxin doses of 100–200 μg. Total ocular neutrophil infiltrations ranged from 250,000 to 800,000 cells/globe. This leukocyte influx was inhibited dose-dependently by topical ocular administration of dexamethasone, with half-maximal inhibition observed at a concentration of 0.01%, w/v. Further validated by the correlation of biochemical results with histological evaluation, the refined methodology described in this report has application in assessing the ophthalmic therapeutic potential of antiinflammatory agents.
Nineteen patients with idiopathic normal pressure hydrocephalus (NPH) were treated with intraventricular shunts. Ten of the 14 who improved and 14 of the total group had systemic hypertension. The ...prevalence of hypertension in both the improved and whole NPH groups was significantly greater than in a control group with dementia (N = 122) and the published prevalence of hypertension in the US population for this age group. Four possible mechanisms for this association are discussed.
Ska and colleagues (1990) reported that patients with possible or probable Alzheimer's Disease (AD) make characteristic errors on a measure of line orientation judgment. We examined errors of line ...orientation judgment in a sample of 31 patients with probable AD, 28 patients with idiopathic Parkinson's disease (PD), and 24 normal elderly controls (NC). Results indicated that, in comparison to NC participants, some error types were made more frequently by patients with PD and patients with AD. No error type, however, was specific to AD alone. In contrast, PD patients were more likely than AD or NC participants to make a specific error in oblique line judgment. This finding is discussed in the context of visuospatial analysis and selective attention in patients with PD.
This unprecedented anthology asks thirty-six leading literary and cultural critics to elaborate on the nature of their profession. With the humanities feeling the pinch of financial and political ...pressures, and its disciplines resting on increasingly uncertain conceptual ground, there couldn't be a better time for critics to reassert their widespread relevance and purpose. These credos boldly defend the function of criticism in contemporary society and showcase its vitality in the era after theory. Essays address literature and politics, with some focusing on the sorry state of higher education and others concentrating on teaching and the fate of the humanities. All reflect the critics' personal, particular experiences. Deeply personal and engaging, these stories move, amuse, and inspire, ultimately encouraging the reader to develop his or her own critical credo with which to approach the world. Reflecting on the past, looking forward to the future, and committed to the power of productive critical thought, this volume proves the value of criticism for today's skeptical audiences.
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