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《Biomaterials》2015
The human mutT homologue MTH1, a nucleotide pool sanitizing enzyme, represents a vulnerability factor and an attractive target for anticancer therapy. However, there is currently a lack of selective and effective platforms for the detection and inhibition of MTH1 in cells. Here, we demonstrate for the first time a gold nanoparticle (AuNP) flares-capped mesoporous silica nanoparticle (MSN) nanoplatform that is capable of detecting MTH1 mRNA and simultaneously suppressing MTH1 activity. The AuNP flares are made from AuNPs that are functionalized with a dense shell of MTH1 recognition sequences hybridized to short cyanine (Cy5)-labeled reporter sequences and employed to seal the pores of MSN to prevent the premature MTH1 inhibitors (S-crizotinib) release. Just like the pyrotechnic flares that produce brilliant light when activated, the resulting AuNP flares@MSN (S-crizotinib) undergo a significant burst of red fluorescence enhancement upon MTH1 mRNA binding. This hybridization event subsequently induces the opening of the pores and the release of S-crizotinib in an mRNA-dependent manner, leading to significant cytotoxicity in cancer cells and improved therapeutic response in mouse xenograft models. We anticipate that this nanoplatform may be an important step toward the development of MTH1-targeting theranostics and also be a useful tool for cancer phenotypic lethal anticancer therapy. 相似文献
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Infectious laryngotracheitis is a significant respiratory disease of chickens that causes huge economic losses due to high morbidity and mortality and reduced egg production. A real-time recombinase polymerase amplification (RPA) assay was developed to accurately detect ILTV. The specific probe and primer sets were carefully designed and screened. The real-time RPA assay was carried out at 39 °C for 30 min, and results were obtained within 15 min. The results of the specificity assay showed no fluorescence signals with other avian-related viruses. The sensitivity of the assay was 1 × 102 copies/μL. The low CV value showed that the assay was reproducible. A total of 115 clinical samples were tested using the real-time RPA assay and the real-time PCR assay in parallel; the coincidence rates of the two detection methods were 100%. The results indicated that the real-time RPA assay is a specific, sensitive, rapid, and useful tool for epidemiological studies and clinical diagnosis, especially in the field and in resource-poor areas. 相似文献
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《International journal of hygiene and environmental health》2019,222(7):1030-1037
In the Netherlands, safe and sufficient drinking water is provided to the general population by ten drinking water companies. To guarantee safe drinking water the World Health Organization (WHO) developed a Water Safety Plan (WSP), a Risk Assessment and a Risk Management (RA/RM) framework. The objective of the study was to identify legally required RA approaches, to document application of RA/RM activities at Dutch drinking water companies and to determine to what extent these RA/RM activities as a whole cover all the elements of the WHO WSP approach. This study could be of interest to both managers of large water utilities and decision makers.The assessment was performed by means of a policy review and interviews with two to four staff members involved in RA/RM from all ten Dutch drinking water companies combined with a joint workshop. The drinking water companies are well aware of the potential hazards and risks that can influence the drinking water quality. To guarantee the supply of safe and sufficient drinking water, the Dutch drinking water sector uses six different legally required RA/RM approaches. This study shows that by using the six legally required RA/RM approaches, all WSP steps are covered. WSP entails a generic risk assessment for identifying all hazards and hazardous events from source to tap, whereas the six legally required RA/RM each focus on specific risks at an advanced level. Each risk assessment provides information on specific hazards and hazardous events covering a part of the water supply chain. These legal requirements are complemented with additional RA/RM activities at sector and water company level such as codes of practices and standard operating procedures. The outcomes of all RA/RM approaches combined provide information from source to tap. When using multiple RA/RM approaches, it is crucial to share and combine information derived from the different activities. 相似文献
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3种霍乱弧菌检测方法在外环境标本中的应用研究 总被引:2,自引:1,他引:1
目的:通过改进霍乱弧菌检测的技术手段,提高外环境标本中霍乱弧菌的检出率。方法:将常规分离鉴定法、PCR检测法和胶体金免疫层析试验法同时用于检测霍乱流行期间的外环境标本,并对其现场应用结果进行比较分析。结果:3种方法检测80份外环境标本霍乱弧菌的结果显示:它们均未出现假阳性,3种方法各有优势,且结果相互符合性好,但也存在各自弱点。结论:只用单一种方法来检测外环境标本霍乱弧菌存在明显不足。建议在外环境霍乱监测中选用胶体金法进行初筛,再用常规法和PCR法检测。最大限度减少漏检的可能性。 相似文献
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食管癌放疗中二次模拟定位临床探讨 总被引:1,自引:0,他引:1
袁晔 《江苏大学学报(医学版)》2002,12(2):133-134
目的:探讨食管癌放疗中间再次定位的必要性和重要性。方法:我院放疗科自1998年10月-2001年3月对356例食管癌患者行单纯放疗或放疗加化疗,356例患者照射全过程都进行二次模拟定位(第一次模拟定位后照射30-40GY/15-20次后进行第2次模拟定位)。比较分析前后二次模拟定位靶中心移位的情况。结果;靶中心移位<0.5cm为157例,移位0.5-1.0cm为130例,移位>1.0cm为69例。全部靶中心移位达55.90%。食管肿瘤长度<5cm靶中心移位27例,5-8cm移位117例,病变长度>8cm移位55例,P<0.05;食管肿瘤发生于颈段,上胸段靶中心移位25例,而中、下段食管移位174例,P<0.01。结论:食管肿瘤外照射达到一定剂量时,靶中心会出现不同程度的移位,肿瘤长度越长靶中心移位会更明显, 肿瘤位置越小,移位亦显著。因此,我们对食管癌患者放疗全过程必需进行2到3次定位,这样才能保证靶中心的精确度,以达到预期治疗目的。 相似文献
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目的探讨NHL采用CHOP方案治疗中护理的重要性.方法对115例NHL采用CTX,750mg/m2 静滴第1日,VCR 1.4g/m2静滴第1.8日,PDN100mg/m2PO第1~5日,每21天为1周期,本组病例用药4~6个周期.结果顺利地完成了115例NHL的化疗,无1例出现化疗作用.结论肿瘤专科护理的措施是顺利完成化疗,减轻副作用,提高生活质量的保证. 相似文献
10.
Purpose. In the National Heart, Lung, and Blood Institute Guidelines for the Diagnosis and Management of Asthma, the expert panel recommends that a written asthma action plan be provided for all patients with asthma. Studies evaluating the usefulness of the asthma action plan in children are limited. We aim to determine exacerbation frequency and usefulness of the asthma action plan in managing exacerbations that occur in a pediatric primary care setting. Methods. Caretakers of asthmatic children attending the general pediatric clinic in an inner-city hospital completed a one-page questionnaire covering topics such as asthma severity, frequency of exacerbations, and possession/usefulness of an asthma action plan. Although controversy exists over the definition of yellow and red zone exacerbations, we defined the yellow zone as symptoms that require albuterol more than three times a day or more than two nights in succession. The red zone was defined as symptoms requiring systemic corticosteroids and/or an urgent physician visit. Results. Seventy of 75 subjects completed the survey. Almost 80% of respondents carried the diagnosis of persistent asthma, whereas the remainder had intermittent asthma. Exacerbation frequency over a 3-month period was determined. Approximately 80% of children experienced at least one yellow zone episode: 42% had one or two yellow zone episodes, and 39.6% had between three and five episodes. Sixty-three percent of patients did not experience a single red zone exacerbation. Almost 75% (44 of 59) of subjects possessed an asthma action plan. Ninety percent (37 of 41) of respondents with action plans found the plan to be useful in managing exacerbations. Conclusion. Approximately four of every five asthmatic children seen in this primary care setting experienced a yellow zone exacerbation at least once during a 3-month period. One third experienced at least one red zone episode. Nine of every 10 caretakers with an action plan reported the asthma action plan to be of value in managing exacerbations. 相似文献