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31.
BACKGROUND: Data on the efficacy of pimecrolimus cream 1% within the first days of treatment are scarce, as in previous studies, the first postbaseline assessment was performed only after 1 week. OBJECTIVE: We sought to investigate the onset of action of pimecrolimus cream 1% in infants with mild to very severe atopic eczema. METHODS: We used pimecrolimus cream 1% (n = 129) or vehicle cream (n = 66) administered in a double-blind manner for 4 weeks and then open-label pimecrolimus cream 1% for 12 weeks, with a 4-week follow-up period. RESULTS: Pimecrolimus cream 1% reduced the mean Eczema Area and Severity Index at 4 weeks by 71.5% compared with an increase of 19.4% with vehicle ( P < .001). The reduction in the Eczema Area and Severity Index with pimecrolimus cream 1% was significant at day 4 (38.5% vs 17.6% increase with vehicle). Significant improvements in caregivers' assessments of pruritus and sleep loss were observed with pimecrolimus cream 1% by day 2 ( P < .03) and day 3 ( P = .002), respectively, compared with vehicle. Responses to pimecrolimus cream 1% were sustained during the open-label phase, and pimecrolimus cream 1% was well tolerated. Symptoms of atopic eczema returned gradually after discontinuation. CONCLUSION: Pimecrolimus cream 1% was well tolerated and effective in patients with mild to very severe atopic eczema, with rapid onset of action and no disease rebound after discontinuation.  相似文献   
32.
The noncytotoxic soluble factor produced by CD8+ T cells inhibits replication of HIV and SIV in vitro and is thought to play a crucial role in combatting infection in vivo. We determined the effect of human CD8+ lymphocytes on the in vitro replication potential of both wild-type and nef-defective mutants of the simian immunodeficiency virus SIVmac251. Although replication of wild-type SIVmac251 in unstimulated human PBMC supplemented with IL-2 was unaffected by the presence of CD8+ T cells, the nef mutants were susceptible to the inhibitory effects. The effect of exogenous IL-2 depended upon the culture conditions: (i) in nonstimulated human PBMC depleted of CD8+ T cells, addition of IL-2 had a positive effect on the growth of the nef-defective viruses; (ii) in total human PBMC, IL-2 appeared to reinforce the CD8+ T-cell-dependent inhibition of the same mutant viruses. This strongly suggests that IL-2 stimulates the noncytotoxic anti-HIV/SIV response of CD8+ cells present in PBMC cultures. PHA stimulation of unfractionated human PBMC overrode the suppression of viral replication by CD8+ T cells. Depletion of activated T cells expressing the IL-2 receptor alpha-chain (CD25+ T cells), present in small amounts in these primary T cell cultures, dramatically reduced viral replication, indicating that the depleted cell population harbors the target cells permissive for viral replication. Furthermore, using neutralizing antibodies we could show that inhibition by the beta-chemokines MIP-1alpha, MIP-1beta, and RANTES and the inhibitory effect of CD8+ lymphocytes on nef mutant SIVmac viruses are harbored on different levels.  相似文献   
33.
In the pars distalis of the pituitary gland in adult and embryonic dwarf (dw/dw) mutant mice, ambiguous cells exhibiting ultrastructural features common to growth hormone (GH) cells and prolactin (Prl) cells were analyzed by means of colloidal gold ultrastructural immunocytochemistry in order to define the functional nature of these peculiar cells. Adult and 18-day embryonic pituitaries from normal (+/+; dw/+) and dwarf (dw/dw) mice were processed with antibodies to GH, Prl, TSH (thyroid-stimulating hormone), ACTH (adrenocorticotropic hormone), LH (luteinizing hormone), FSH (follicle-stimulating hormone), and HCG (chorionic gonadotropic hormone). In the adult and embryonic dwarf pituitaries, the ambiguous cells reacted negatively to all of the antibodies except for anti-ACTH, which labeled them well. In addition, the ACTH-positive cells showed a much wider variety of shapes and granule size and distribution, as compared with normal adults. In the embryos, this variability in ACTH cell morphology occurred not only in dwarf embryos, but in their normal counterparts as well. The results thus suggest that adult dwarf pituitaries may retain an embryonic or incompletely differentiated form of ACTH cells. © 1993 Wiley-Liss, Inc.  相似文献   
34.
Hepatic fibrogenesis is a consequence of hepatic stellate cells that become activated and transdifferentiate into a myofibroblastic phenotype with the ability to proliferate and synthesize large quantities of extracellular matrix components. In this process, platelet-derived growth factor (PDGF) is the most potent stimulus for hepatic stellate cell proliferation and migration, and is overexpressed during active hepatic fibrogenesis. This cytokine binds to the PDGF receptor type beta, activates Ras and sequentially propagates the stimulatory signal sequentially via phosphorylation of Raf-1, MEK and the extracellular-signal regulated kinases ERK1/ERK2. Hepatic injury is associated with both increased autocrine PDGF signaling and upregulation of PDGF receptor. In this study, we report that a dominant-negative soluble PDGF-beta receptor consisting of a chimeric IgG containing the extracellular portion of the PDGF receptor type beta blocks HSC activation and attenuates fibrogenesis induced by ligation of the common bile duct in rats. In culture-activated hepatic stellate cells, the soluble receptor blocks phosphorylation of endogenous PDGF receptor, phosphorylation of the ERK1/EKR2 signal and reduces proliferative activities of HSC. In vivo, both the delivery of the purified soluble PDGF antagonist and the administration of adenoviruses expressing the artificial transgene were able to reduce significantly the expression of collagen and alpha-smooth muscle actin. Our results demonstrate that PDGF plays a critical role in the progression and initiation of experimental liver fibrogenesis, and suggest that early anti-PDGF intervention should have a therapeutical impact on the treatment of liver fibrogenesis.  相似文献   
35.
The region spanning the tumor necrosis factor (TNF) cluster in the human major histocompatibility complex (MHC) has been implicated in susceptibility to numerous immunopathological diseases, including type 1 diabetes mellitus and rheumatoid arthritis. However, strong linkage disequilibrium across the MHC has hampered the identification of the precise genes involved. In addition, the observation of "blocks" of DNA in the MHC within which recombination is very rare, limits the resolution that may be obtained by genotyping individual SNPs. Hence a greater understanding of the haplotypes of the block spanning the TNF cluster is necessary. To this end, we genotyped 32 human leukocyte antigen (HLA)-homozygous workshop cell lines and 300 healthy control samples for 19 coding and promoter region SNPs spanning 45 kb in the central MHC near the TNF genes. The workshop cell lines defined 11 SNP haplotypes that account for approximately 80% of the haplotypes observed in the 300 control individuals. Using the control individuals, we defined a further six haplotypes that account for an additional 10% of donors. We show that the 17 haplotypes of the "TNF block" can be identified using 15 SNPs.  相似文献   
36.
Autoimmunity may be associated with acute or chronic inflammation. In order to determine whether the inflammatory marker C-reactive protein (CRP) was an indicator of inflammatory events that precede, predict, or associate with islet autoimmunity or type 1 diabetes, CRP was measured in sequential antibody-negative, seroconversion, and follow-up-positive samples from 65 prospectively studied islet autoantibody-positive children. Although changes in CRP concentrations were observed in some children, overall CRP concentrations were similar in antibody-negative samples (median, 0.21 mg/L), antibody-positive samples (median, 0.26 mg/L), and samples at seroconversion (median, 0.26 mg/L). CRP concentrations at diabetes onset (median, 0.59 mg/L) were not significantly increased over antibody-negative samples (P = 0.07). CRP concentrations did not predict diabetes development. CRP concentrations were related to age (r = 0.26; P < 0.001) and were increased in samples obtained from October to January (P < 0.001). These findings suggest that CRP concentrations are not a valuable marker of progression to type 1 diabetes and highlight the importance of correcting analyses for seasonal variations.  相似文献   
37.
Summary Immunofluorescence and colloidal gold immunocytochemistry were used to analyze the regional distribution of adrenocorticotropic (ACTH) cells and their ultrastructural relationship with growth hormone (GH) cells in adult and 17-day embryonic little (lit/lit) mice that exhibit GH cell defects. Adult lit/lit pituitaries lack the distinctive regionalization of ACTH cells that characterizes normal pituitaries, although typical ultrastructural relationships occur between some ACTH and GH cells. In 17-day embryos, normal and lit/lit pituitaries show similar distributions of ACTH cells. However, in lit/lit pituitaries the pars distalis cells are more loosely arranged, with poorly defined clusters and cords, than in normal glands. The results indicate that whereas the lack of ACTH cell regionalization in adult glands may be a secondary effect of the GH cell defect, the differences in overall integrity of the 17-day embryonic glands suggest the possibility of a developmental disturbance during early stages of gestation in this mutant.Supported by research grant No. HD12308 from the National Institute of Child Health and Human Development, National Institutes of Health (USA)  相似文献   
38.
Summary LY163443,1-[2-hydroxy-3-propyl-4-{[4-(1H-tetrazol-5-ylmethyl)-phenoxy]methyl}phenyl]ethanone, antagonized LTD4-induced contractions of guinea pig ileum, trachea, and lung parenchyma. Tracheal contractions to LTE4 were also inhibited by LY163443. The compound had minimal effect against ileal responses to LTC4 and parenchymal contractions to LTB4. Furthermore, LY163443.had little to no effect against contractions of isolated smooth muscles to histamine, bradykinin, PGF2, carbachol, serotonin or U46619. LY163443, given by oral administration to guinea pigs, blocked LTD4-induced increases in total pulmonary impedance (TPI). Similar responses elicited by histamine or U46619 were unaffected. Increases in TPI in response to i.v. administration of LTC4 were antagonized by LY163443 given by the same route. Ovalbumin challenge also increased TPI in guinea pigs previously sensitized against this antigen. In such animals, pretreated with pyrilamine, propranolol, and indomethacin, oral administration of LY163443 blocked the increase in TPI caused by ovalbumin. Additionally, LTD4 given intradermally to guinea pigs caused a vascular leakage which was suppressed by prior oral administration of LY163443. Finally, LY163443 relaxed isolated guinea pig trachea previously contracted with LTD4, histamine, or carbachol. Relaxation of tissues contracted by these latter two agonists suggested some inherent airway smooth muscle relaxant properties of the molecule. This was further demonstrated by showing some bronchodilator activity in an in vivo setting. Thus, this pharmacologic profile indicates that LY163443, or a member of the same chemical family, warrants consideration as a possible therapeutic agent in the treatment of asthma and in diseases characterized by an overproduction of LTD4 and LTE4.Presented in part at the meeting of The Federation of American Societies for Experimental Biology, April 1985, Anaheim, California.  相似文献   
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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Vor dem Hintergrund der derzeitigen COVID-19-Pandemie entstand die Idee zur Durchführung einer Studie, in der die...  相似文献   
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