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Dahle MK Øverland G Myhre AE Stuestøl JF Hartung T Krohn CD Mathiesen Ø Wang JE Aasen AO 《Infection and immunity》2004,72(10):5704-5711
Sepsis caused by gram-positive bacteria lacking lipopolysaccharide (LPS) has become a major and increasing cause of mortality in intensive-care units. We have recently demonstrated that the gram-positive-specific bacterial cell wall component lipoteichoic acid (LTA) stimulates the release of the proinflammatory cytokines in Kupffer cells in culture. In the present study, we have started to assess the signal transduction events by which LTA induces the production of tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), and the anti-inflammatory cytokine IL-10 in rat Kupffer cells. LTA was found to trigger phosphorylation of mitogen-activated protein kinases (MAPK) (p38 MAPK and ERK 1/2) and protein kinase B (PKB). Compared to LPS, LTA was more potent in inducing PKB phosphorylation after 40 min, although we found that the cytokine responses were similar. For both bacterial molecules, blocking phosphatidylinositol 3-kinase (PI3-K; Ly294002) or Janus kinase 2 (JAK-2; AG490) particularly affected the induction of IL-6 and IL-10 release, whereas TNF-alpha levels were strongly reduced by inhibition of Src family tyrosine kinases (PP2). All three cytokines were reduced by inhibition of p38 MAPK (SB202190) or the broad-range tyrosine kinase inhibitor genistein, whereas IL-6 release was particularly blocked by inhibition of ERK 1/2 (PD98059). Divergences in the regulatory pathways controlling TNF-alpha, IL-10, and IL-6 production in Kupffer cells following LPS or LTA stimulation may create a basis for understanding how the balance between pro- and anti-inflammatory cytokines is regulated in the liver following infections by gram-positive or gram-negative bacteria. 相似文献
6.
Hans-JØrgen Malling 《Clinical reviews in allergy & immunology》1992,10(3):213-236
Conclusion The problems of elucidating the role of mold spores in allergy are related to both an absence of detailed information about
allergen exposure, and lack of standardized allergen extracts. Provided qualitatively and quantitatively optimal extracts
are available, the IgE-diagnostic tests are of equal value in diagnosing mold sensitization, as with other aeroallergens.
In the opinion of the author, the specific diagnosis represents the combination of demonstrated IgE reactivity (using diagnostic
tests) and clinical symptoms related to exposure to the causative allergen. In order to diagnose organ-specific disease, an
unequivocally positive challenge in the relevant shock organ is essential. The rational approach to diagnosing mold allergy
is, based on the clinical history, to use skin test as the primary screening test. SPT has the highest sensitivity (few false
negative reactions) and, compared to ICT, few irrelevant positive reactions, and should consequently be used to screen for
IgE sensitization in the diagnostic workup. Because of the lower sensitivity, RAST is not optimal as the initial test, but
as a result of high specificity (few false positive reactions) it is optimal as a confirmatory test for the presence of specific
IgE. The clinical relevance of the IgE sensitization should be confirmed by reevaluating the history to ensure that the patients
do in fact have symptoms caused by the allergen (Table 2). Challenge tests are normally indicated only if the diagnosis of
allergen sensitization implies therapeutic interventions, such as allergen-specific immunotherapy. 相似文献
7.
Melissa C. Kanar Dwain L. Thiele Monika Østensen Peter E. Lipsky 《Journal of clinical immunology》1988,8(1):69-79
Natural killer (NK)-like activity against a renal carcinoma cell line, Cur, was assessed. There was no spontaneous killing of Cur cells by human peripheral blood mononuclear cells in 4-hr assays. Cur killing was observed in 18-hr assays, but the magnitude of killing was variable and always markedly less than that against K562. Cur killing was mediated by a nonadherent, nonphagocytic lymphocyte, the activity of which could be modulated both positively and negatively by monocytes or their products. Preincubation of effectors with monocyte supernatant, interleukin 1 (IL-1), -interferon (IFN), or interleukin 2 (IL-2) greatly increased the magnitude of Cur killing and accelerated the kinetics of lysis. The addition of prostaglandin E2 (PGE2) duringin vitro activation of NK by IL-2 profoundly inhibited subsequent Cur lysis, whereas only minimal inhibition of K562 lysis was noted. However, following activation with IL-2, lysis of Cur targets was less sensitive to the inhibitory effects of PGE2. Removal of Leu 11b(+), OKM1(+), orl-leucylleucine methyl ester-sensitive cells markedly decreased both Cur and K562 lysis. Moreover, CD16(+) cells purified with the fluorescence-activated cell sorter were found to mediate Cur killing. Whereas Cur and K562 lysis is mediated by phenotypically similar effector cells, the present studies demonstrate that the cytotoxic functions defined by the ability to lyse these two targets differ in response to a variety of immunoregulatory stimuli. 相似文献
8.
Huisman JA; Paulussen RJ; Geurts TB; Odink J; Rekers H 《Human reproduction (Oxford, England)》1997,12(1):34-38
The objective was to demonstrate bioequivalence between s.c. and i.m.
administration of Humegon (FSH/LH ratio 1:1) and Normegon (FSH/LH ratio
3:1). In two randomized, single-centre, cross-over studies, 18 healthy
volunteers on each formulation were assigned to one of the two
administration sequences. Subjects were given single doses of one of the
above gonadotrophins after endogenous gonadotrophin production had first
been suppressed using high-dose oral contraceptive. Subsequently, rate
(Cmax, tmax) and extent (AUC) of absorption of follicle stimulating hormone
(FSH) and luteinizing hormone (LH) were determined for 14 days. For Cmax
and AUC, analysis of variance (ANOVA) was performed on log-transformed data
and for tmax ANOVA was performed on ranks. Intramuscular and s.c.
injections of Humegon were bioequivalent with respect to the main
pharmacokinetic parameters, being AUC and Cmax of FSH absorption.
Intramuscular and s.c. injections of Normegon were bioequivalent with
respect to the AUC of FSH and not bioequivalent with respect to the Cmax of
FSH. For tmax of FSH as well as for most LH variables of both preparations,
bioequivalence could not be proven due to the high intra- and
interindividual variability and/or concentrations being close to the
detection limit. Thus, the main pharmacokinetic FSH variables after i.m.
and s.c. administration of Humegon and Normegon were bioequivalent.
相似文献
9.
Nes Ragnhild Bang Yu Baeksan Hansen Thomas Vedaa Øystein Røysamb Espen Nilsen Thomas S. 《Quality of life research》2022,31(8):2295-2305
Quality of Life Research - We examined multidimensional, heterogeneous reactions to the COVID-19 pandemic and associated measures to provide further insights into the developmental processes of... 相似文献
10.
Aasdahl Lene Vasseljen Ottar Gismervik Sigmund Østgård Johnsen Roar Fimland Marius Steiro 《Journal of occupational rehabilitation》2021,31(4):721-728
Journal of Occupational Rehabilitation - Purpose There is a lack of results on long-term effects of return to work interventions. We previously reported that an inpatient multimodal occupational... 相似文献