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排序方式: 共有4751条查询结果,搜索用时 46 毫秒
41.
Association of β1‐Adrenergic,M2‐Muscarinic Receptor Autoantibody with Occurrence and Development of Nonvalvular Atrial Fibrillation 下载免费PDF全文
42.
Fukami N Ramachandran S Takenaka M Weber J Subramanian V Mohanakumar T 《American journal of transplantation》2012,12(4):867-876
Using a murine model, we demonstrated that endobronchial administration of antibodies (Abs) to major histocompatibility complex (MHC) class I results in cellular infiltration, epithelial metaplasia, fibrosis and obstruction of the small airways (obliterative airway disease [OAD]) mediated predominantly by Th17 responses to self-antigens. This resembles bronchiolitis obliterans syndrome developed following human lung transplantation. Since B cells play a crucial role in induction of autoimmune responses, we defined the role of B cells and its antigen presenting properties in induction of OAD in this study. Anti-MHC class I was administered endobronchially in B(-/-) and wild-type mice. In contrast to wild type, B(-/-) animals did not demonstrate cellular infiltration, epithelial metaplasia and obstruction of airways following anti-MHC. Frequency of K-α1 tubulin and CollagenV-specific IL-17 cells was significantly decreased in B(-/-) mice. As expected, Abs against self-antigens and germinal center formation were not developed in B(-/-) mice. Thus, we conclude that B cells and its antigen presenting capacity play an important role in induction of immune responses to self-antigens and immunopathogenesis of OAD following the administration of anti-MHC. Therefore, strategies to block B-cell and its antigen presenting functions should be considered for preventing the development of chronic rejection. 相似文献
43.
F. Waldron‐Lynch S. Deng P. Preston‐Hurlburt O. Henegariu K. C. Herold 《American journal of transplantation》2012,12(10):2652-2662
Preclinical testing of human therapeutic monoclonal antibodies has been limited in murine models due to species differences in pharmacokinetics and biologic responses. To overcome these constraints we developed a murine skin transplant model in humanized mice and used it to test human monoclonal antibody therapy. Neonatal NOD/SCID/IL2Rγcnull mice (NSG) were reconstituted with human CD34+ hematopoietic stem cells (hNSG). When adult, these mice rejected MHC mismatched murine C57BL/6J skin grafts. Rejection required adequate reconstitution with human cells. There was diffuse infiltration of the epidermis and dermis with hCD8 and hCD4 cells in rejected grafts by immunohistochemistry. Studies with B6/MHC class I and II knockout mice donors indicated that neither is required for rejection. Graft rejection was associated with the development of effector and central memory T cells and an increase in serum immunoglobulins. We also tested the effects of teplizumab (anti‐CD3 mAb) and found it could delay skin graft rejection, whereas ipilimumab (anti‐CTLA‐4 [cytotoxic T‐lymphocyte antigen‐4] mAb) treatment accelerated rejection. These findings demonstrate that hNSG mice reliably and predictably reject a xenogenic mouse skin graft by a human T cell mediated mechanism. The model can be utilized to investigate the ability of human immunotherapies to enhance or suppress functional human immune responses. 相似文献
44.
Breast cancer patients do not commonly receive anti-estrogens prior to surgical excision. We reviewed a cohort of patients who received preoperative anti-estrogen therapy after baseline biopsy and then had a repeat biopsy after several weeks on treatment. Patients with estrogen receptor positive tumors received anastrozole and fulvestrant in combination with gefitinib. Core needle biopsies were performed at day 1 and 21, and tumors were completely excised if operable at day 112. All patients were postmenopausal. Following treatment, tumors had degenerative changes including smudged nuclei, decreased nuclear size, intranuclear vacuoles, vacuolated cytoplasm, and increased cellular discohesion. In addition, increased tubule formation and intracytoplasmic lumina were seen in 6/9 cases (66.7%) and decreased mitotic rate was demonstrated in 7/9 cases (77.8%). These findings indicate increased differentiation of the tumor cells in response to anti-estrogen therapy and that may correlate with clinical response. 相似文献
45.
V. de Parades N. Fathallah P. Blanchard J.‐D. Zeitoun B. Bennadji P. Atienza 《Colorectal disease》2012,14(12):1512-1515
Aim The aim of this study was to analyse the characteristics of horseshoe tract formation in anal fistula. Method We retrospectively analysed the data from all consecutive patients who underwent surgery for an anal fistula from November 2004 to March 2011. A horseshoe tract was defined as a circumferential extension connecting both sides of the anorectum. Results During the period of analysis, 1876 patients were operated on for a fistula. Of these, 82 (4.4%) had a horseshoe extension. The majority (72%) were male and the median age was 46 (17–84) years. The primary tract was high transsphincteric in 90% of cases and the primary opening was posterior in 65% of cases. The location of the horseshoe extension was posterior in 66% of cases with spread in the deep perianal space in 62%. In all, 71% were cryptoglandular and 24% were seen in Crohn’s disease (20). Of the 62 non‐Crohn’s patients previous treatment was common and included surgery (42), antibiotics alone (41) and non‐steroidal anti‐inflammatory drugs (21). Conclusion Horseshoe extension in anal fistula is uncommon. With Crohn’s disease excepted, the majority had had previous treatment. 相似文献
46.
Sutcliffe S Grubb Iii RL Platz EA Ragard LR Riley TL Kazin SS Hayes RB Hsing AW Andriole GL;on behalf of the Urologic Diseases in America Project 《BJU international》2012,110(7):1050-1059
Study Type – Therapy (cohort) Level of Evidence 4 What's known on the subject? and What does the study add? Accumulating evidence suggests that inflammation may contribute to the development of BPH and LUTS. Therefore, it is plausible that anti‐inflammatory agents, such as aspirin and other NSAIDs, may reduce the risk of BPH/LUTS, as was observed in a recent analysis of daily aspirin use and BPH/LUTS risk in the Olmsted County Study of Urinary Symptoms and Health Status in Men. The present study, conducted in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial, found no association for recent aspirin or ibuprofen use with the risk of BPH/LUTS.
OBJECTIVE
- ? To investigate the relationship between non‐steroidal anti‐inflammatory drug (NSAID) use and the incidence of benign prostatic hyperplasia (BPH)‐related outcomes and nocturia, a lower urinary tract symptom (LUTS) of BPH, in light of accumulating evidence suggesting a role for inflammation in BPH/LUTS development.
PATIENTS AND METHODS
- ? At baseline, participants in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial completed questions on recent, regular aspirin and ibuprofen use, BPH surgery, diagnosis of an enlarged prostate/BPH, and nocturia. Participants in the intervention arm also underwent a digital rectal examination (DRE), from which prostate dimensions were estimated, as well as a prostate‐specific antigen (PSA) test. Only participants in the intervention arm without BPH/LUTS at baseline were included in the analysis (n= 4771).
- ? During follow‐up, participants underwent annual DREs and PSA tests, provided annual information on finasteride use, and completed a supplemental questionnaire in 2006–2008 that included additional questions on diagnosis of an enlarged prostate/BPH and nocturia.
- ? Information collected was used to investigate regular aspirin or ibuprofen use in relation to the incidence of six BPH/LUTS definitions: diagnosis of an enlarged prostate/BPH, nocturia (waking two or more times per night to urinate), finasteride use, any self‐reported BPH/LUTS, prostate enlargement (estimated prostate volume ≥30 mL on any follow‐up DRE) and elevation in PSA level (>1.4 ng/mL on any follow‐up PSA test).
RESULTS
- ? Generally, null results were observed for any recent, regular aspirin or ibuprofen use (risk ratio = 0.92–1.21, P= 0.043–0.91) and frequency of use (risk ratios for one category increase in NSAID use = 0.98–1.11, P‐trends = 0.10–0.99) with incident BPH/LUTS.
CONCLUSION
- ? The findings obtained in the present study do not support a protective role for recent NSAID use in BPH/LUTS development.
47.
Experimental autoimmune encephalomyelitis (EAE) is an animal model of demyelinating autoimmune disease, such as multiple sclerosis (MS), which is characterized by central nervous system white matter lesions, microglial activation, and peripheral T‐cell infiltration secondary to blood–brain barrier disruption. We have previously shown that treatment with tuftsin, a tetrapeptide generated from IgG proteolysis, dramatically improves disease symptoms in EAE. Here, we report that microglial expression of Neuropilin‐1 (Nrp1) is required for tuftsin‐driven amelioration of EAE symptoms. Nrp1 ablation in microglia blocks microglial signaling and polarization to the anti‐inflammatory M2 phenotype, and ablation in either the microglia or immunosuppressive regulatory T cells (Tregs) reduces extended functional contacts between them and Treg activation, implicating a role for microglia in the activation process, and more generally, how immune surveillance is conducted in the CNS. Taken together, our findings delineate the mechanistic action of tuftsin as a candidate therapeutic against immune‐mediated demyelinating lesions. GLIA 2016;64:923–936 相似文献
48.
Natalia Lizama Terry Slevin Simone Pettigrew 《Australian and New Zealand journal of public health》2019,43(6):529-531
Objective: Several studies have examined the characteristics of anti‐smoking advertisements that are associated with quitting behaviour. Some studies use researchers or graduate students to code advertisement characteristics, while others recruit smokers or members of the general public. The aim of this study was to assist future campaign development by assessing whether anti‐smoking advertisement characteristics are coded differently by smokers and ‘experts’ (individuals with knowledge of health promotion, public health or advertising). Methods: A total of 49 smokers and 42 experts coded anti‐smoking advertisements according to four key characteristics (emotional/cognitive approach, negative/positive tone, message frame, and main message) and the use of eight executional techniques. Chi‐squared tests were used to measure differences in coding outcomes between smokers and experts. Results: There were significant differences between smokers and experts in the coding of all key characteristics and four of the eight executional techniques. Compared with smokers, experts were more likely to perceive advertisements as negative in tone and as inducing fear. Conclusions: Smokers and experts perceived the characteristics of anti‐smoking advertisements differently. Implications for public health: Differences between smokers and experts may need to be taken into account where studies use either of these groups to code advertisements for campaign development or evaluation purposes. 相似文献
49.
The Meth Project and Teen Meth Use: New Estimates from the National and State Youth Risk Behavior Surveys 下载免费PDF全文
In this note, we use data from the national and state Youth Risk Behavior Surveys for the period 1999 through 2011 to estimate the relationship between the Meth Project, an anti‐methamphetamine advertising campaign, and meth use among high school students. During this period, a total of eight states adopted anti‐meth advertising campaigns. After accounting for pre‐existing downward trends in meth use, we find little evidence that the campaign curbed meth use in the full sample. We do find, however, some evidence that the Meth Project may have decreased meth use among White high school students. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
50.
Silymarin attenuates paraquat‐induced lung injury via Nrf2‐mediated pathway in vivo and in vitro 下载免费PDF全文
Feng Zhao Danyang Shi Tiegang Li Lizhuo Li Min Zhao 《Clinical and experimental pharmacology & physiology》2015,42(9):988-998
The present study aims to investigate the impacts and mechanisms of silymarin on paraquat (PQ)‐induced lung injury in vivo and in vitro. In in vivo experiments, a total of 32 male Sprague‐Dawley (SD) rats were randomly divided into four groups. The rats were killed on day 3. Histopathological changes in lung tissue were examined using HE and Masson's trichrome staining. Biomarkers of neutrophil activation, pulmonary oedema, pulmonary fibrosis, lung permeability and oxidative stress were detected. Several proinflammatory mediators and antioxidant related proteins were measured. In in vitro experiments, A549 cells were transfected with Nrf2 special siRNA to investigate the roles of Nrf2. The results show that silymarin administration abated PQ‐induced lung histopathologic changes, decreased inflammatory cell infiltration and lung wet weight/dry weight (W/D) ratio, suppressed myeloperoxidase (MPO) activity and nitric oxide (NO)/inducible nitric oxide synthases (iNOS) expression, downregulated hydroxyproline (HYP) levels, reduced total protein concentration and proinflammatory mediator release, and improved oxidative stress (malondialdehyde, MDA; superoxide dismutase, SOD; catalase, CAT; and glutathione peroxidase, GSH‐Px) in lung tissue and serum. Meanwhile, treatment with silymarin upregulated the levels of nuclear factor‐erythroid‐2‐related factor 2 (Nrf2), heme oxygenase‐1 (HO‐1) and NAD(P)H:quinone oxidoreductase‐1(NQO1). However, the addition of Nrf2 siRNA reduced the expression of Nrf2‐mediated antioxidant protein HO‐1 and thus reversed the protective effects of silymarin against oxidative stress and inflammatory response. These results suggest that silymarin may exert protective effects against PQ‐induced lung injury. Its mechanisms were associated with the Nrf2‐mediated pathway. Therefore, silymarin may be a potential therapeutic drug for lung injury. 相似文献