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41.
Crohn's disease(CD) is a chronic idiopathic inflammatory disease of gastrointestinal tract characterizedby segmental and transmural involvement of gastrointestinal tract. Ileocolonic and colonic/anorectal is a most common and account for 40% of cases and involvement of small intestine is about 30%. Isolated involvement of stomach is an extremely unusual presentation of the disease accounting for less than 0.07% of all gastrointestinal CD. To date there are only a few documented case reports of adults with isolated gastric CD and no reports in the pediatric population. The diagnosis is difficult to establish in such cases with atypical presentation. In the absence of any other source of disease and in the presence of nonspecific upper gastrointestinal endoscopy and histological findings, serological testing can play a vital role in the diagnosis of atypical CD. Recent studies have suggested that perinuclear anti-neutrophil cytoplasmic antibody and anti-Saccharomycescervisia antibody may be used as additional diagnostic tools. The effectiveness of infliximab in isolated gastric CD is limited to only a few case reports of adult patients and the long-term outcome is unknown.  相似文献   
42.
戴俊杰  曾庆意  丁美萍 《浙江医学》2016,38(12):977-980
目的探讨重症肌无力(MG)患者血清Titin抗体和Ryanodine受体(RyR)抗体的临床意义。方法采用ELISA法检测61例MG患者和35例健康体验者(正常对照组)的血清Titin抗体、RyR抗体、AChR抗体。结果MG组Titin抗体和RyR抗体阳性率均显著高于对照组(均P<0.001);合并胸腺瘤MG(MGT)组患者Titin抗体阳性率明显高于未合并胸腺瘤MG(NTMG)组(P<0.01);MGT组和NTMG组患者RyR抗体阳性率差异无统计学意义(P>0.05);晚发型MG患者中Titin抗体和RyR抗体阳性率均明显高于早发型MG患者(均P<0.05);全身型或重症型(ⅡA、ⅡB、Ⅲ、Ⅳ型)Titin抗体阳性率显著高于眼肌型(Ⅰ型)(P<0.01),而两组间RyR抗体阳性率未见统计学差异(P>0.05);MG患者Titin抗体和RyR抗体水平与肌无力严重程度相关分析呈正相关(r=0.520、0.487,均P<0.01)。结论Titin抗体和RyR抗体检测有助于MG的诊断,且Titin抗体有助于鉴别MG患者是否伴随胸腺瘤及进行Osserman分型。Titin抗体与RyR抗体水平还与MG患者病情的严重程度相关,可应用于评估MG患者的病情与预后。  相似文献   
43.
44.
Purpose: To report a novel plasminogen gene mutation and detection of anti-plasminogen antibodies in a patient with ligneous conjunctivitis successfully treated with 60% fresh frozen plasma (FFP). Methods: Retrospective data collected on a 45-year-old Caucasian female presenting with unilateral chronic membranous lesions. Results: Laboratory investigation demonstrated decreased plasminogen antigen level, plasminogen activity, and rate of plasminogen activation by u-PA or t-PA, and elevated plasminogen activator inhibitor-1. Anti-plasminogen IgG and IgA antibodies were detected. DNA analysis revealed a novel Asp432Asn heterozygous missense mutation in the plasminogen gene (exon 11). The patient was treated with topical 60% FFP, achieved complete remission after four months, and remained membrane-free for over five years of follow-up. Conclusions: A novel plasminogen gene mutation, deficiency of plasminogen antigen and activity, and anti-plasminogen IgG and IgA antibodies were identified in a patient with adult-onset ligneous conjunctivitis. Sixty percent FFP maintained this patient disease-free for over five years.  相似文献   
45.
Introduction: The addition of monoclonal antibody (mAb) epidermal growth factor receptor (EGFR) inhibitors to classic chemotherapy doublet backbones has improved survival of metastatic colorectal cancer (mCRC). However, the role of triple-drug chemotherapy regimens in combination with an anti-EGFR mAb inhibitor is not yet clear.

Areas covered: The activity of triple-drug chemotherapy regimens when combined with an anti-EGFR mAb in mCRC patients is examined. We describe the overall safety and tolerability profiles based on a literature review of all published phase I and II clinical trials in this setting. Drug exposure, tumor mutational status, and metastases resectability are discussed. A review of PubMed and abstracts of major oncology congresses from 2009 to 2018, with MeSH and full-text search terms for clinical trials of anti-EGFR for ‘metastatic’ or ‘advanced’ ‘colorectal cancer/adenocarcinoma’ was implemented. Only English language publications were included.

Expert opinion: Efficacy data from phase II trials are promising, but the safety profiles are not as encouraging; the development of severe diarrhea and acneiform rash limit the drug exposure that is critical for improved outcomes. Phase II studies of these triplet chemotherapy/anti-EGFR mAb combinations have focused on conversion therapy in liver-limited disease or in the first-line setting in advanced disease. The identification of biomarkers of response and toxicity may support the use of personalized medicine and more precise design of phase III trials.  相似文献   

46.
47.
《Vaccine》2019,37(30):4184-4194
Kaposi sarcoma-associated herpesvirus (KSHV) is an emerging pathogen and the causative agent of multiple cancers in immunocompromised patients. To date, there is no licensed prophylactic KSHV vaccine. In this study, we generated a novel subunit vaccine that incorporates four key KSHV envelope glycoproteins required for viral entry in diverse cell types (gpK8.1, gB, and gH/gL) into a single multivalent KSHV-like particle (KSHV-LP). Purified KSHV-LPs were similar in size, shape, and morphology to KSHV virions. Vaccination of rabbits with adjuvanted KSHV-LPs generated strong glycoprotein-specific antibody responses, and purified immunoglobulins from KSHV-LP-immunized rabbits neutralized KSHV infection in epithelial, endothelial, fibroblast, and B cell lines (60–90% at the highest concentration tested). These findings suggest that KSHV-LPs may be an ideal platform for developing a safe and effective prophylactic KSHV vaccine. We envision performing future studies in animal models that are susceptible to KSHV infection, to determine correlates of immune protection in vivo.  相似文献   
48.
《Vaccine》2019,37(35):4947-4955
A major obstacle to obtaining relevant results in cancer vaccination has been the lack of identification of immunogenic antigens. Dendritic cell (DC)-based cancer vaccines used preventively may afford protection against tumor inoculation, but the effect of antigen choice on anti-tumor protection is not clear. When using irradiated syngeneic tumor cells to load DCs, tumor self-antigens are provided, including tumor-associated antigens (TAAs) and neoantigens generated by tumor mutations. On the other hand, allogeneic tumor cells could only supply shared TAAs. To assess the advantages of each source in protective vaccination, we analyzed in C57BL/6 mice the effect of loading DCs with irradiated syngeneic B16-F1 or allogeneic Cloudman melanoma cells; both cell lines were characterized by whole exome sequencing and RNAseq. Tumor cell components from the two irradiated cell lines were efficiently internalized by DCs, and transported to MHC-class II positive tubulovesicular compartments (MIICs). DCs loaded with allogeneic irradiated Cloudman cells (DC-ApoNecALLO) induced a partially effective anti-melanoma protection, although Cloudman and B16-F1 cells share the expression of melanocyte differentiation antigens (MDAs), cancer-testis antigens (CTAs) and other TAAs. DCs loaded with syngeneic B16-F1 cells (DC-ApoNecSYN) established a more potent and long-lasting protection and induced a humoral anti-B16F1 response, thus suggesting that neoepitopes are needed for inducing long-lasting protection.  相似文献   
49.
《Vaccine》2020,38(6):1526-1534
Despite decades of vaccination, surveillance, and biosecurity measures, H5N2 low pathogenicity avian influenza (LPAI) virus infections continue in Mexico and neighboring countries. One explanation for tenacity of H5N2 LPAI in Mexico is the antigenic divergence of circulating field viruses compared to licensed vaccines due to antigenic drift. Our phylogenetic analysis indicates that the H5N2 LPAI viruses circulating in Mexico and neighboring countries since 1994 have undergone antigenic drift away from vaccine seed strains. Here we evaluated the efficacy of a new recombinant fowlpox virus vector containing an updated H5 insert (rFPV-H5/2016), more relevant to the current strains circulating in Mexico. We tested the vaccine efficacy against a closely related subcluster 4 Mexican H5N2 LPAI (2010 H5/LP) virus and the historic H5N2 HPAI (1995 H5/HP) virus in White Leghorn chickens. The rFPV-H5/2016 vaccine provided hemagglutinin inhibition (HI) titers pre-challenge against viral antigens from both challenge viruses in almost 100% of the immunized birds, with no differences in number of birds seroconverting or HI titers among all tested doses (1.5, 2.0, and 3.1 log10 mean tissue culture infectious doses/bird). The vaccine conferred 100% clinical protection and a significant decrease in oral and cloacal virus shedding from 1995 H5/HP virus challenged birds when compared to the sham controls at all tested doses. Virus shedding titers from vaccinated 2010 H5/LP virus challenged birds significantly decreased compared to sham birds especially at earlier time points. Our results confirm the efficacy of the new rFPV-H5/2016 against antigenic drift of LPAI virus in Mexico and suggest that this vaccine would be a good candidate, likely as a primer in a prime-boost vaccination program.  相似文献   
50.
Human epidermal growth factor receptor 4 (HER4) isoforms have oncogenic or tumor suppressor functions depending on their susceptibility to proteolytic cleavage and HER4 intracellular domain (4ICD) translocation. Here, we report that the neuregulin 1 (NRG1) tumor suppressor mechanism through the HER4 JMa/CYT1 isoform can be mimicked by the agonist anti‐HER4 Ab C6. Neuregulin 1 induced cleavage of poly(ADP‐ribose) polymerase (PARP) and sub‐G1 DNA fragmentation, and also reduced the metabolic activity of HER3?/HER4+ cervical (C‐33A) and ovarian (COV318) cancer cells. This effect was confirmed in HER4 JMa/CYT1‐, but not JMa/CYT2‐transfected BT549 triple‐negative breast cancer cells. Neuregulin 1 favored 4ICD cleavage and retention in mitochondria in JMa/CYT1‐transfected BT549 cells, leading to reactive oxygen species (ROS) production through mitochondrial depolarization. Similarly, the anti‐HER4 Ab C6, which binds to a conformational epitope located on a.a. 575‐592 and 605‐620 of HER4 domain IV, induced 4ICD cleavage and retention in mitochondria, and mimicked NRG1‐mediated effects on PARP cleavage, ROS production, and mitochondrial membrane depolarization in cancer cells. In vivo, C6 reduced growth of COV434 and HCC1187 tumor cell xenografts in nude mice. Biasing 4ICD trafficking to mitochondria with anti‐HER4 Abs to mimic NRG1 suppressor functions could be an alternative anticancer strategy.  相似文献   
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