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1.
Mice treated with a single injection of formalin-fixed Coxiella burnetii showed a significant increase in resistance to vaccinia virus (VV) infection compared to untreated mice. C. burnetii stimulated dramatically high levels of nitric oxide (NO) in the serum of treated mice, suggesting that NO might play a role in resistance to virus infection. To test this hypothesis, the effect of C. burnetii treatment on VV replication was examined in NOS2-/- and wild-type mice. C. burnetii treatment inhibited VV replication in both the knockout and wild-type mice but the effect was significantly greater in the NOS2-/- mice. Experiments in IFNgamma receptor knockout mice indicated that the nonspecific antiviral immunity induced by C. burnetii was dependent on IFNgamma and not NO. In the absence of NO, indoleamine 2,3-dioxygenase (IDO) was increased in C. burnetii-treated mice and this may contribute to the accelerated virus clearance in NOS2-/- mice.  相似文献   
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Summary We have previously shown that specific antibodies (Mab 32/Ab 301) against tumour necrosis factor (TNF) enhance its antiviral activity in vaccinia virus-infected mice. In the present study, TNF alone was found to have antiviral activity against herpes simplex virus-1 (HSV-1). Antibody enhancement was found, both in vivo and in vitro, at lower TNF doses. The magnitude of the TNF-induced antiviral response was dependent upon the genetic background of the mouse. C57BL/6 mice were very sensitive to the antiviral activity of TNF, which was inhibited by the free radical scavenger butylated hydroxyanisole (BHA). TNF plus Mab 32 induced a significant antiviral effect in L929 cells which was associated with pronounced CPE. The CPE was largely reversed in the presence of BHA, and furthermore, TNF antiviral activity was significantly reversed in the presence of BHA. Specific inhibitors of nitric oxide synthetase, lipoxygenase or cyclo-oxygenase did not influence either the CPE or growth kinetics of HSV-1, suggesting that neither reactive nitrogen intermediates nor arachidonic acid metabolites were involved in the antiviral mechanism of TNF. This, together with observed increases in Cu/Zn SOD levels in virus infected cells, suggests that reactive oxygen intermediates may have a role in the direct control of HSV-1 growth and that free radicals may play a part in the antiviral activity induced by TNF.  相似文献   
3.
Psoriasis is a multifactorial skin disease characterised by epidermal abnormalities and infiltration by lymphocytes and polymorphonuclear leukocytes (PMN). Skin-derived antileukoproteinase (SKALP), also known as elafin, is a potent inhibitor of human leukocyte elastase and proteinase 3, two PMN-derived proteinases implicated in tissue destruction and leukocyte migration. We have shown that, at least at the protein level, SKALP is significantly decreased in lesional skin of patients with pustular psoriasis compared with plaque-type psoriasis. This finding raised the possibility that SKALP could be one of the candidate genes for pustular forms of psoriasis. We therefore performed single strand conformation polymorphism (SSCP) analysis on the SKALP gene to screen for mutations/polymorphisms in the exons of 30 patients with plaque-type psoriasis, 15 patients with pustular psoriasis and 48 healthy controls. In exon 1 a polymorphism was detected at position + 43 relative to the translation start site, resulting in a substitution of threonine for alanine in the signal peptide. In the promoter region a dinucleotide repeat polymorphism was identified. Both polymorphisms were not associated with pustular psoriasis, or psoriasis in general. Our data indicate that the decrease in SKALP activity in pustular psoriasis is not caused by mutations in the coding region of the gene, and that there is no allelic association between pustular psoriasis and SKALP gene polymorphisms.  相似文献   
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We analyzed for the first time the expression of chemokines in subpopulations of the murine immune system at the single-cell level. We demonstrate in vitro and in a model of murine listeriosis that macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, regulated on activation normal T cell expressed and secreted (RANTES), and activation-induced, T cell-derived, and chemokine-related cytokine (ATAC)/lymphotactin are cosecreted to a high degree with IFN-gamma by activated individual natural killer (NK), CD8(+) T, and CD4(+) T helper 1 (Th1) cells. Functionally, ATAC and the CC chemokines cooperate with IFN-gamma in the up-regulation of CD40, IL-12, and tumor necrosis factor-alpha, molecules playing a central role in the effector phase of macrophages. Our data indicate that (i) MIP-1alpha, MIP-1beta, RANTES, and ATAC are not only chemoattractants but also coactivators of macrophages, (ii) MIP-1alpha, MIP-1beta, RANTES, and ATAC constitute together with IFN-gamma a group of "type 1 cytokines," and (iii) these cytokines act together as a functional unit that is used by NK cells in the innate phase and then "handed over" to CD8(+) T cells in the antigen-specific phase of the immune defense, thus bridging the two components of a Th1 immune reaction.  相似文献   
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Established treatments for psoriasis act ei-ther on hyperproliferation, inflammation, aberrant epidermal differentiation or a combination of these aspects of the disease. Potential new drugs for treatment of psoriasis or other disorders with abnormalities in epidermal differentiation can be identified by high-throughput screening of large compound libraries using surrogate markers for the disease. Here we describe a screening model to detect pharmacologically active drugs in two keratinocyte-based, 96-well culture models that use expression of cytokeratin 10 (CK10) and skin-derived antileucoprotease (SKALP)/elafin as markers for normal and psoriatic differentiation, respectively, and allow multiple parameters to be determined from a single well. In this model we tested a number of compounds in a pharmacological range from 10(-7) to 10(-5) M, including known antipsoriatic drugs, and experimental drugs that are potentially useful in the treatment of psoriasis. All-trans-retinoic acid, dithranol and the p38 mitogen-activated protein (MAP) kinase inhibitor SB220025 displayed a strong inhibitory effect on SKALP expression while cyclosporin A, dexamethasone, the vitamin D(3) derivative calcipotriol and the p38 MAP kinase inhibitor SB203580 showed only moderate inhibition. Methotrexate and dimethylfumarate did not affect the expression of SKALP. With respect to CK10 expression, all-trans-retinoic acid, calcipotriol, SB203580 and SB220025 exhibited strong inhibition while dithranol showed only moderate suppression of this normal differentiation marker. Expression levels of CK10 were not significantly affected by dexamethasone, methotrexate, cyclosporin A or dimethylfumarate. This model system parallels most, but not all, findings on the in vitro effect of known antipsoriatic drugs on keratinocytes. In addition, the model identifies p38 MAP kinase inhibitors as potent suppressors of differentiation-associated gene expression. Although further delineation and validation of this model is required, we conclude that the system is amenable to down-scaling and application as a high-throughput screen for differentiation-modifying compounds.  相似文献   
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J E Rolph  R L Kravitz  K McGuigan 《JAMA》1991,266(15):2093-2097
OBJECTIVE.--To evaluate the usefulness of malpractice claims data for identifying (1) physicians who are prone to negligent errors and (2) physician and hospital characteristics associated with particular kinds of errors. DESIGN.--Retrospective review of physician malpractice claim records. SETTING.--Large New Jersey physician malpractice insurer. PARTICIPANTS.--Physicians practicing obstetrics and gynecology, general surgery, anesthesiology, or radiology and covered by the insurance carrier for any portion of 1977 through 1989. MAIN OUTCOME MEASURES.--Claims were classified into 11 clinical error categories comprising three broad groups: patient management problems, technical performance problems, and staff coordination problems. Outcomes were expressed as per-physician frequency of claims due to negligence and proportion of claims associated with various types of errors. RESULTS.--Using 5 years of claims history to predict long-term claims proneness was more accurate than chance alone by 57% in obstetrics and gynecology, 33% in general surgery, 11% in anesthesiology, and 15% in radiology. Cross-validated recursive partitioning showed that among physician characteristics, only specialty was predictive of physician error profiles. For physician claims arising in acute care hospitals, hospital size and location in addition to hospital services discriminated among different error profiles; the cross-validated accuracy of this method was 69% compared with 22% accuracy achieved by random prediction. CONCLUSION.--Use of physicians' malpractice claims histories to target individuals for education or sanctions is problematic because of the only modest predictive power of such claims histories.  相似文献   
10.
In 2016, we described that missense variants in parts of exons 30 and 31 of CREBBP can cause a phenotype that differs from Rubinstein–Taybi syndrome (RSTS). Here we report on another 11 patients with variants in this region of CREBBP (between bp 5,128 and 5,614) and two with variants in the homologous region of EP300. None of the patients show characteristics typical for RSTS. The variants were detected by exome sequencing using a panel for intellectual disability in all but one individual, in whom Sanger sequencing was performed upon clinical recognition of the entity. The main characteristics of the patients are developmental delay (90%), autistic behavior (65%), short stature (42%), and microcephaly (43%). Medical problems include feeding problems (75%), vision (50%), and hearing (54%) impairments, recurrent upper airway infections (42%), and epilepsy (21%). Major malformations are less common except for cryptorchidism (46% of males), and cerebral anomalies (70%). Individuals with variants between bp 5,595 and 5,614 of CREBBP show a specific phenotype (ptosis, telecanthi, short and upslanted palpebral fissures, depressed nasal ridge, short nose, anteverted nares, short columella, and long philtrum). 3D face shape demonstrated resemblance to individuals with a duplication of 16p13.3 (the region that includes CREBBP), possibly indicating a gain of function. The other affected individuals show a less specific phenotype. We conclude that there is now more firm evidence that variants in these specific regions of CREBBP and EP300 result in a phenotype that differs from RSTS, and that this phenotype may be heterogeneous.
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