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排序方式: 共有966条查询结果,搜索用时 15 毫秒
1.
John P. Sundberg Kathleen A. Silva Victoria E. Kennedy John J. Wilson Nicholas E. Gott Beth A. Sundberg Derry C. Roopenian 《Experimental dermatology》2019,28(9):1091-1093
2‐deoxy D‐glucose (2DG) was tested for efficacy in treating alopecia areata using the C3H/HeJ skin graft model. 2DG has proven to be efficacious in treatment of various mouse models of autoimmunity with minimal serious side effects noted. This agent has been shown to normalize abnormally activated T‐cell populations while also preventing cell surface expression of NKG2D; key factors defining alopecia areata disease progression. Daily oral ingestion of 2DG via drinking water to mice with patchy or diffuse alopecia areata for 16 weeks failed to prevent expansion of alopecia or cause regrowth of hair in treated mice. Histologically, there were no differences between treated and control groups. These results indicate that, while 2DG is effective for some autoimmune diseases, it was not efficacious for the cell‐mediated autoimmune mouse disease, alopecia areata. 相似文献
2.
Methylmercury induced alterations in the nerve growth factor level in the developing brain. 总被引:1,自引:0,他引:1
L L?rkfors A Oskarsson J Sundberg T Ebendal 《Brain research. Developmental brain research》1991,62(2):287-291
Pre- and early postnatal stages in the development of the central nervous system (CNS) are very sensitive to the toxic effects of methylmercury. The influence of methylmercury on the level of nerve growth factor (NGF) during the development of CNS was studied. Sprague-Dawley rats were exposed indirectly throughout the fetal and suckling periods until weaning on postnatal day 25 (P 25) via their dams given methylmercury in the diet (3.9 mg/kg diet). In addition, after weaning offsprings were exposed directly to methylmercury via the diet until postnatal day 50 (P 50). The level of NGF was analyzed in cortical areas and in the septum with a sensitive enzyme immunoassay. The pups exposed to MeHg exhibited a 50% elevation in the level of NGF in the hippocampus on P 25 and P 50 compared to control animals. Concomitantly, the level of NGF decreased by 30% in the septum on P 25 and P 50, suggesting that the retrograde transport of NGF from hippocampus to septum could be affected by the exposure of methylmercury. The exact mechanism by which the low level of mercury is affecting the NGF concentration in the developing brain is yet unknown. The increase of NGF in the hippocampus and the decrease of NGF measured in the septum could reflect altered conditions for neurotrophic support in these areas of the brain as a result of the exposure to heavy metal. Thus, this finding might indicate a connection between exposure of heavy metals and neurodegeneration, such as that found in the basal forebrain in Alzheimer's disease. 相似文献
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TP Amadeu† AB Seabra‡ MG de Oliveira‡ AMA Costa† 《Journal of the European Academy of Dermatology and Venereology》2007,21(5):629-637
BACKGROUND: Nitric oxide (NO) plays a key role in wound repair and S-nitrosothiols like S-nitrosoglutathione (GSNO) are well known NO donors. METHODS: Animals were separated in two groups and submitted to excisional wounds on the dorsal surface at the first day. GSNO (100 microm)-containing hydrogels were topically applied on the wound bed in the GSNO group, daily, during the first 4 days. Control group was topically treated with hydrogel without GSNO for the same period. Wound contraction and re-epithelialization were measured. Animals were sacrificed 21 days after wounding. Samples of lesion and normal tissue were formalin-fixed, paraffin embedded for histological analysis. RESULTS: Wound contraction, measured 14 and 21 days after wounding, was greater in the GSNO group than in the control group (P<0.05 for both). The re-epithelialized wound area, measured 14 days after wounding, was higher in the GSNO group than in the control group (P<0.05). A higher amount of inflammatory cells was observed in superficial and deep areas of the granulation tissue of the control group compared to the GSNO group. Twenty-one days after wounding, thin red-yellow collagen fibers arranged perpendicularly to the surface were found in the granulation tissue of the control group, whereas in the GSNO-treated group collagen fibers were thicker and arranged parallel to the surface. Increased number of mast cells was observed in the GSNO group compared with that in the control group. Vascularization and myofibroblast distribution were similar in both groups. CONCLUSION: Topical application of GSNO-containing hydrogel during the early phases of rat cutaneous wound repair accelerates wound closure and re-epithelialization and affects granulation tissue organization. 相似文献
5.
Logistic regression was used to analyze the influence of pretransplant herpesvirus antibodies, in both patients and donors, on the development of acute graft-versus-host disease in 111 consecutive HLA-identical bone marrow recipients. In bivariate analysis, recipient seropositivity for cytomegalovirus (P = 0.01), donor seropositivity for herpes simplex virus (P = 0.02), and low bone marrow cell dosage (P less than 0.05) were associated with a high incidence of grade II-IV acute GVHD. In multivariate analysis the P values were P less than 0.05 for a positive recipient CMV serology and P = 0.07 for a positive donor HSV serology. Positive serology for 1-2 herpes-viruses among recipients or donors both resulted in a 12% incidence of grade II-IV acute GVHD. Positive serology for 3-4 herpesviruses among patients or donors resulted in an incidence of 32% and 38% of acute GVHD, respectively (P less than 0.05). It is concluded that recipient and donor pretransplant herpesvirus immunity can be used to calculate the risk of moderate-to-severe acute GVHD. 相似文献
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7.
An analysis of the components in UW solution using the isolated perfused rabbit liver 总被引:11,自引:0,他引:11
The isolated perfused rabbit liver model has been used to determine the essential components of the UW solution for hepatic preservation by simple cold storage. Livers were stored on ice for 48 hr after initial flushing with the solution being tested, and then reperfused at 38 degrees C in an isolated perfusion circuit; bile flow and enzyme (SGOT, SGPT, and LDH) release during a 2-hr period were recorded. All solutions tested contained phosphate (25 mM) as a buffer and magnesium sulfate (5 mM). Sodium can be substituted for potassium without adverse effects. Lactobionate, raffinose and glutathione cannot be omitted; all other components can be eliminated without altering the effectiveness of the solution in this model. 相似文献
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9.
A novel papillomavirus was cloned from hyperkeratotic cutaneous lesions of a Persian domestic cat. The Felis domesticus papillomavirus (FdPV-1) genome counts 8300 bp and has a typical genome structure with an early region (E1, E2, E4, E6, E7), a late region (L1, L2), and a noncoding upstream regulatory region (URR or NCR1) between the end of L1 and the beginning of E6. The FdPV-1 also shows an unusual second noncoding region (NCR2) of 1.3 kb, situated between the end of E2 and the beginning of L2. This NCR2 is uniquely related to a similar region in the canine oral papillomavirus (COPV). Phylogenetic analysis places FdPV-1 together with COPV, the cottontail rabbit papillomavirus, human papillomavirus type 1 (HPV-1), and HPV-63 in the group of the benign cutaneous papillomaviruses. The position of FdPV-1 in the phylogenetic tree allows us to hypothesize that already in an early phase of the papillomavirus molecular evolution, a split occurred into viruses with a dual tropism primarily for cutaneous epithelia but also secondarily for mucosal surfaces, and viruses with a specific monotropism for mucosal surfaces. The close relationship between FdPV-1 and COPV, and between their Canidae and Felidae hosts, supports the hypothesis that papillomaviruses have speciated and coevolved together with their hosts throughout vertebrate evolution. A papillomavirus mutation rate of 0.73 to 0.96 x 10(-8) nucleotide substitutions per base per year was calculated. 相似文献
10.
Salnikov AV Roswall P Sundberg C Gardner H Heldin NE Rubin K 《Laboratory investigation; a journal of technical methods and pathology》2005,85(4):512-521
A pathologically elevated interstitial fluid pressure (IFP) is a characteristic of both clinical and experimental carcinoma. The soluble TGF-beta receptor type II-murine Fc:IgG2A chimeric protein (Fc:TbetaRII) lowers IFP in the KAT-4 experimental model for anaplastic thyroid carcinoma. Analyses of messenger RNA (mRNA) expressions by Affymetrix microarrays and RNase protection assays, as well as of protein expressions identified tumor macrophages as targets for Fc:TbetaRII. Treatment with Fc:TbetaRII reduced albumin extravasation, increased coverage of alpha-smooth muscle actin-positive cells and reduced expression of NG2, a marker of activated pericytes, in KAT-4 carcinoma blood vessels. Specific inhibition of interleukin-1 (IL-1), a major cytokine produced by activated macrophages, lowered carcinoma IFP to a similar degree as Fc:TbetaRII but had no significant effect on the parameters of blood vessel maturation. Neither Fc:TbetaRII nor inhibition of IL-1 changed blood vessel density. Finally, pretreatment of KAT-4 carcinomas with Fc:TbetaRII increased the antitumor efficacy of doxorubicin. Our data emphasize a potential role of tumor macrophages in carcinoma physiology and identify these cells as potential stromal targets for treatment aimed to improve efficacy of chemotherapy. 相似文献