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AIM: To investigate whether non-canonical autophagy transport receptor cell cycle progression 1 (CCPG1) is involved in the corneal antifungal immune response. METHODS: Human corneal epithelial cells (HCECs) and human myeloid leukemia mononuclear cells (THP-1) macrophages stimulated by Aspergillus fumigatus (A. fumigatus) were used as cell models. The expression of CCPG1 mRNA was detected by qRT-PCR. Western blot was used to determine the protein expression of CCPG1 and interleukin-1β (IL-1β). The dectin-1 neutralizing antibody was used to detect the association between dectin-1 and CCPG1. Immunofluorescence was used to observe the colocalization of CCPG1 and C-type lectin-like receptor-1 (CLEC-1) in THP-1 macrophages. RESULTS: The expression of CCPG1 started to increase at 4h after infection and increased in a time-dependent manner in HCECs and THP-1 macrophages. With dectin-1 neutralizing antibody pretreatment, the expression of IL-1β was down-regulated. CCPG1 up-regulation in response to A. fumigatus infection was independent of dectin-1. Immunofluorescence showed the colocalization of CCPG1 and CLEC-1 in THP-1 macrophages. CONCLUSION: As a specific autophagy protein of non-canonical autophagy pathway, CCPG1 is involved in corneal infection with A. fumigatus.  相似文献   
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《Clinical microbiology and infection》2020,26(11):1555.e9-1555.e14
ObjectivesEvidence of false-positive galactomannan enzyme immunoassay (GM-EIA) results associated with intravenous immunoglobulin (IVIG) administration is scarce. Here, we aimed to determine the false-positive rate of GM-EIA after IVIG administration and to identify the related factors.MethodsStandard GM-EIA was performed using diluted and pure human IVIG samples with and without heat treatment. We also included adult patients who had at least one GM-EIA result within 1 week of IVIG administration for analysis. Those who had prior invasive aspergillosis within 1 year before IVIG therapy were excluded. The clinical characteristics and galactomannan index (GMI) kinetics between patients with false-positive and true-positive GMI were compared.ResultsAll diluted and pure IVIG samples tested positive for GM. Heat treatment resulted in the considerable elevation of GMI. Of 48 patients with positive GM-EIA results within 1 week of IVIG administration, 22 (45.8%) were considered to have false-positive antigenaemia (false-positive group, FPG). After the completion of IVIG administration, a decline in GMI was observed in all FPG patients but in only 18 out of 26 patients (69.2%) with true-positive results (true-positive group, TPG). By 7, 14, and 18 days of IVIG administration, GMI reverted to negative values in 7/15 (46.7%), 18/20 (90%) and 22/22 (100%) FPG patients, respectively, and 6/24 (25%), 14/24 (58.3%), and 16/26 (61.5%) of TPG patients, respectively. The TPG was more likely to have two or more consecutively positive GMIs after IVIG administration than the FPG (adjusted odds ratio, 9.01; 95% confidence interval, 1.99–40.9).ConclusionsIVIG treatment may produce false-positive GM-EIA results. A positive GMI among patients receiving human IVIG should be interpreted with caution.  相似文献   
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目的:分析痰曲霉菌阳性支气管哮喘(简称哮喘)患者的临床特点及探讨抗真菌药物干预对这类哮喘患者的临床应用价值。方法收集2013年3月至2014年3月收治的92例痰曲霉菌阳性的哮喘患者的临床资料设为观察组,随机选取同期92例痰曲霉菌阴性的哮喘患者作为对照组。对照分析2组患者的临床特点;并对观察组患者实施抗真菌药物干预。结果观察组患者的特征:病程长,与对照组比较,差异有统计学意义(t =3.41,P <0.01)。男性患者、有特殊职业史患者多,使用非正规来源药物时间长,有长期使用广谱抗生素、糖皮质激素史,与对照组比较差异有统计学意义(χ2=8.03、3.92、11.21,P <0.01);而年龄在2组间差异无统计学意义(t =0.12,P >0.05)。观察组行抗真菌干预后:肺功能、哮喘控制测试评分明显提高,嗜酸粒细胞百分比及总 IgE 明显降低,与对照组比较差异有统计学意义(t =3.16、3.51、3.58、5.61,P <0.01)。结论哮喘合并曲霉菌致敏可以造成哮喘症状加重并难以控制,对于难治性哮喘患者当常规治疗无效且具有有曲霉菌阳性临床特征表现的患者,要及时进行相应检测,并及早进行短期抗真菌干预,对于那些没有检测条件的基层医院建议进行试验性抗真菌药物干预将有助于哮喘症状的控制。  相似文献   
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Poor clinical outcomes for invasive aspergillosis are associated with antifungal resistance. Performing antifungal susceptibility tests on clinically relevant Aspergillus isolates from patients and environmental regions with known azole resistance is recommended. The aim of the study was to assess the presence of azole resistance in clinical Aspergillus spp. isolates and those from hospital environments and farmlands within a 40 km radius of the hospital. Clinical Aspergillus spp. isolates were cultured, as well as environmental Aspergillus spp. isolates obtained from air samples. Samples were subcultured in azole‐containing agar plates. Isolates with a positive screening test were subjected to YeastOne methods to determine their minimum inhibitory concentrations of antifungals. Resistance mechanisms were investigated in the azole‐resistant Aspergillus spp. isolates. No azole‐resistant clinical or environmental A flavus, A oryaze, A niger or A terreus isolates were found in the present study. All A fumigatus clinical isolates were azole‐susceptible. Seven A fumigatus environmental isolates were associated with cyp51A mutations, including two that harboured TR34/L98H mutations with S297T/F495I substitutions, two with TR34/L98H mutations and three with TR46/Y121F/T289A mutations. One of these isolates was collected from farmland, one was from A ward and five were from B ward. The proportion of azole‐resistant A fumigatus was 10.2% (6/59) and 3.2% (1/31) in the hospital environments and the farmlands near the hospital, respectively. The results showed that azole‐resistant A fumigatus existed within hospital environments. This emphasises the importance of periodic surveillance in hospital environments and monitoring for the emergence of azole‐resistant A fumigatus clinical isolates.  相似文献   
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Curcumin nanoparticles were most recently considered in medical research because of their antibacterial properties. The main objective of the study was to develop the green synthesis and antibacterial activity of curcumin nanoparticles using Curcuma longa. The processing of curcumin nanoparticles was carried out after the collection, identification, and extraction of curcumin. The effect of a sample on the synthesis of nanoparticles, such as curcumin aqueous concentrations (5, 10, and 20 mg/ml) and curcumin nanoparticles (5, 10, and 20 mg/ml), and the antibacterial effect of these nanoparticles on Escherichia coli, Staphylococcus aureusPseudomonas aeruginosa, Klebsiella pneumoniae, and the fungal strain Aspergillus niger. For examining antibacterial and anti-fungal activity disc diffusion method was performed, followed by the zone of inhibition. According to X-ray diffraction and scanning electron microscope analysis, nanoparticles have spherical shapes and size of 42.64 nm. Results showed that a high dose of 20 mg/ml curcumin nanoparticles have more antibacterial activity than curcumin extracts in E. coli as it showed the largest diameter of zone of inhibition as compared to other doses. Other bacterial and fungal strains also showed significant results but E. coli was most prominent. The biosynthesis of curcumin nanoparticles using an aqueous extract of C. longa is a clean, inexpensive, and safe method that has not been used any toxic substance and consequently does not have side effects. Since several pathogenic species have acquired antibiotic resistance, the combination of curcumin with various nanoparticles would be beneficial in the cure of pathogenic diseases.  相似文献   
9.
侵袭性曲霉病是由致病曲霉菌引起的危及生命的真菌感染,主要致病菌为烟曲霉,而唑类抗真菌药物是临床治疗的首选。目前已上市的唑类抗真菌药物包括伊曲康唑,伏立康唑,泊沙康唑和伊沙康唑。然而,流行病学研究发现曲霉菌对唑类抗真菌药物的耐药率呈逐年上升趋势,给临床治疗造成了威胁。其中,Cyp51A蛋白突变、外排系统高表达以及环境耐药机制等多种因素都参与唑类抗真菌药物的耐药。因此,本文综述近年来有关曲霉菌对唑类抗真菌药物的耐药机制,以期为耐药监测、耐药菌控制和新药研发提供理论依据。  相似文献   
10.
目的研究一株海洋来源真菌Aspergullus versicolor NM-021杂色曲霉的化学成分及其抗肿瘤活性。方法利用硅胶柱色谱、Sephadex LH-20凝胶柱色谱、半制备HPLC等色谱技术对其化学成分进行分离、纯化;通过NMR、MS方法,结合与文献报道的数据比对,对化合物的结构进行鉴定。运用细胞毒活性筛选模型对其抗肿瘤活性进行初步评价。结果从该菌株中分离得到了2个蒽醌类化合物2H-6-O-Methylaverufin(1)和6-O-Methylaverufin(2)。生物活性测试结果表明,化合物1对人结肠癌和食管癌具有一定的抑制活性。结论从该菌株中分离得到1个新的具有细胞增殖抑制活性的蒽醌类化合物(1)。  相似文献   
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