Aptamers are a group of artificial oligonucleotides identified by exponential enrichment system evolution technology (Selective expansion of ligands by exponential enrichment, SELEX). Aptamers have been widely used in basic research, clinical diagnostics, and nano-technology. In this article we will introduce the technology of aptamer and summarize its applications in medical microbiology.
Aptamers, Nucleotide ; biosynthesis ; genetics ; Microbiological Techniques ; methods ; Microbiology ; SELEX Aptamer Technique ; methods ; trends

To analyze the molecular basis of the variation of the pathogenicity of the influenza B virus, we rescued a recombinant virus with a deletion in the carboxyl terminal of the NS1 protein using reverse genetics based on the parental virus B-S9 of B/Yamagata/16/88. A mutant strain with a deletion of 171 amino acids in the carboxyl terminal of the NS1 protein was named "B-L5". BALB/c mice were inoculated with 3 X 105 EID50 of B-L5 and the parental virus B-S9, respectively. Then, weight changes, survival, and viral titers were documented. During 3 days post-inoculation (dpi) to 7 dpi, the weight of mice infected with B-S9 decreased. However, the weight of mice infected with B-L5 showed weight decreases only at 2 dpi, and quickly recovered at 3 dpi. B-S9 and B-L5 could replicate in the lungs of BALB/c mice. However, viral titers in the lungs of mice infected with B-L5 were 7900-times lower than those of mice infected with B-S9 at 3 dpi. Viral titers in the lungs of mice infected with B-L5 were not detected at 6 dpi. These results showed that, compared with the parent virus B-S9, the mutant virus B-L5 showed lower pathogenicity in BALB/c mice. Our study suggests that deletion of the carboxyl terminal of the NS1 protein decreases the pathogenicity of the influenza B virus. Establishment of a reverse-genetics system for the B influenza virus will provide a platform for studying its pathogenesis, and mechanism of transmission, and for developing live-attenuated influenza B virus vaccines.
Animals ; Body Weight ; Dogs ; Female ; HEK293 Cells ; Humans ; Influenza B virus ; genetics ; pathogenicity ; physiology ; Madin Darby Canine Kidney Cells ; Mice ; Mice, Inbred BALB C ; Sequence Deletion ; Survival Analysis ; Viral Load ; genetics ; Viral Nonstructural Proteins ; chemistry ; genetics ; Virulence

Objective To analyze the correlation between sleep quality and job burnout among nurses and to explore the moderating effect of mindfulness in the correlation. Methods From September 2017 to March 2018, we selected 240 nurses in the Second Affiliated Hospital of Wenzhou Medical University by convenience sampling. The general information, job burnout, sleep quality and mindfulness were investigated with the General Information Questionnaire, Maslach Burnout Inventory General Survey (MBI-GS), Pittsburgh Sleep Quality Index (PSQI) and Mindful Attention Awareness Scale (MAAS). A total of 240 questionnaires were sent out and collected with 226 valid questionnaires. Results Among 226 nurses, the score of job burnout was (3.04±1.01). The total score and dimension scores of job burnout were positively correlated with the score of sleep quality (r=0.389-0.422,P＜0.01) and negatively correlated with the score of mindfulness (r=-0.198--0.296,P＜ 0.05). Structural equation model multi-group analysis showed that mindfulness could moderate correlation between sleep and job burnout (P＜0.01). Conclusions Nurses have a low level of sleep quality and a high level of job burnout. Mindfulness can moderate correlation between sleep and job burnout among nurses. Increasing mindfulness of nurses can improve job burnout of them.

Objective To investigate the workaholism, organization overwork climate and achievement motives of clinical nurses in Class Ⅲ Grade A hospitals, and to explore the influencing factors of workaholism. Methods From August to October 2018, we selected clinical nurses from two ClassⅢ Grade A hospitals in Zhejiang Province by convenience sampling as subjects. The investigation was carried out with the General Information Questionnaire, Work Addiction Scale for Nurses, Overwork Climate Questionnaire and the Achievement Motives Scale (AMS). The SPSS 20.0 was used to statistical description, simple correlation and multiple linear regression. A total of 750 questionnaires were sent out and 687 of them were collected with 91.6% for the effective recovery rate. Results Among 687 clinical nurses of Class Ⅲ Grade A hospitals, the scores of workaholism, organization overwork climate, pursuing success motive dimension and avoiding failure in AMS were (59.11±13.59), (29.14±5.72), (2.79±0.65) and (2.58±0.61) respectively. Simple correlation showed that the correlated factors of workaholism of clinical nurses included overwork climate, pursuing success, avoiding failure, genders, education levels, titles, personal connection and number of children (P＜ 0.05). Multiple linear regression found that the influencing factors of workaholism were pursuing success motive, organization overwork climate, contract system personal connection and education levels (P＜0.05). Conclusions Hospital managers should pay attention to nurses' tendency of workaholism and take measures to control workaholism of nurses with obvious workaholism tendency in an appropriate level so as to promote the long-term and stable hospital development.

Rift Valley fever (RVF) is an acute, febrile zoonotic disease that is caused by the RVF virus (RVFV). RVF is mainly prevalent on the Arabian Peninsula, the African continent, and several islands in the Indian Ocean near southeast Africa. RVFV has been classified by the World Organisation for Animal Health (OIE) as a category A pathogen. To avoid biological safety concerns associated with use of the pathogen in RVFV neutralization assays, the present study investigated and established an RVFV pseudovirus-based neutralization assay. This study used the human immunodeficiency virus (HIV) lentiviral packaging system and RVFV structural proteins to successfully construct RVFV pseudoviruses. Electron microscopy observation and western blotting indicated that the size, structure, and shape of the packaged pseudoviruses were notably similar to those of HIV lentiviral vectors. Infection inhibition assay results showed that an antibody against RVFV inhibited the infective ability of the RVFV pseudoviruses, and an antibody neutralization assay for RVFV detection was then established. This study has successfully established a neutralization assay based on RVFV pseudoviruses and demonstrated that this method can be used to effectively evaluate antibody neutralization.
Africa ; Animals ; Blotting, Western ; HIV ; Indian Ocean ; Islands ; Methods ; Microscopy, Electron ; Product Packaging ; Rift Valley fever virus ; Rift Valley Fever ; Zoonoses

To develop a specific, rapid, and convenient immunochromatography assay (ICA) to detect the rabies antibody in clinical sample from immuned dogs by rabies vaccine. Colloidal gold particles labeled with purified rabies virus (CVS11) were used as the detector reagent. The staphylococcal protein A (SPA) and pured rabbit anti-rabies virus IgG were blotted on the test and control regions of nitrocellulose membrane. Then the strip was assembled with sample pad, absorbing pad, and dorsal shield. The assay samples (261 dog's serum) were collected from Wildlife Rabies Disease Diagnostic Laboratories of Ministry of Agriculture in China, Institute of Military Veterinary, Academy of Military Medical Sciences and other six provinces, including rabies virus positive and negative serum. The performance of the strip was compared to fluorescent antibody virus neutralization test. The neutralizing antibody titer could be detected above 0.5 IU. The strip did not change of performance when stored at room temperature for 12 months. It may offer reference of neutralizing antibody titer level after dogs immuned rabies vaccine and determin whether the dogs need to be immuned again.
Animals ; Antibodies, Neutralizing ; analysis ; blood ; Antibodies, Viral ; analysis ; blood ; Dogs ; Gold Colloid ; Immunochromatography ; methods ; Rabies ; prevention & control ; veterinary ; Rabies Vaccines ; immunology ; Rabies virus ; immunology ; Reagent Strips ; Sensitivity and Specificity ; Vaccination

Monoclonal antibody-based therapy has achieved great success and is now one of the most crucial therapeutic modalities for cancer therapy. The first monoclonal antibody authorized for treating human epidermal growth receptor 2 (HER2)-positive breast cancer is trastuzumab. However, resistance to trastuzumab therapy is frequently encountered and thus significantly restricts the therapeutic outcomes. To address this issue, tumor microenvironment (TME) pH-responsive nanoparticles (NPs) were herein developed for systemic mRNA delivery to reverse the trastuzumab resistance of breast cancer (BCa). This nanoplatform is comprised of a methoxyl-poly (ethylene glycol)-b-poly (lactic-co-glycolic acid) copolymer with a TME pH-liable linker (Meo-PEG-Dlink _m -PLGA) and an amphiphilic cationic lipid that can complex PTEN mRNA via electrostatic interaction. When the long-circulating mRNA-loaded NPs build up in the tumor after being delivered intravenously, they could be efficiently internalized by tumor cells due to the TME pH-triggered PEG detachment from the NP surface. With the intracellular mRNA release to up-regulate PTEN expression, the constantly activated PI3K/Akt signaling pathway could be blocked in the trastuzumab-resistant BCa cells, thereby resulting in the reversal of trastuzumab resistance and effectively suppress the development of BCa.