ABSTRACT
BACKGROUND: At present, there is a lack of standardized preparation methods of sperm antigen for the detection of antisperm antibody (AsAb). To screen sperm antigen mimotopes from a phage display random peptide library and use them to establish an enzyme-linked immunosorbent assay (ELISA) for the detection of AsAb, immunoglobulins were extracted from the sera of rabbits with positive AsAb and negative AsAb, respectively, by the saturated ammonium sulfate method, and a phage display 12-mer peptide library was affinity panned by the extracted immunoglobins coated on the ELISA plate. Then, the obtained positive phage clones were identified by ELISA and sent for sequencing and peptides synthesis. Last, a diagnostic ELISA was established to detect clinical serum and seminal plasma samples. RESULTS: A total of sixty phage clones were chosen by affinity panning, and sixteen of them reacted positively with AsAb in indirect ELISA and sandwich ELISA. Following DNA sequencing and translation, the peptide sequences of the sixteen positive clones were obtained. By comparison in Blast database, four of sixteen positive clones were found to be closely related to male reproduction. Two (#1 and #25) of four mimotopes were synthesized, and an ELISA method was established using the two mimotopes as sperm specific antigens. One hundred and thirty-four serum samples and seventy-four seminal plasma samples from infertile couples were analyzed by the established ELISA with #1 and #25 mimotopes, respectively. The positive rates of AsAb in serum samples were 20.15% (27/134) for #1 and 11.19% (15/134) for #25, respectively, and the coincidence rate between them was 91.04% (122/134). The positive rates of AsAb in seminal plasma samples were 1.35% (1/74) for both #1 and #25, and the coincidence rate was 100%. CONCLUSION: Sperm antigen mimotopes can be obtained successfully by the phage display technique, and can be used as standard sperm specific antigens to establish an ELISA method for the detection of AsAb.
RéSUMé: CONTEXTE: À ce jour, il n'existe pas de méthodes normalisées de préparation d'antigènes spermatiques pour la détection des anticorps anti-spermatozoïdes (ACAS). Dans le but d'élaborer un tel test ELISA (enzyme-linked immunosorbent assay), nous avons extrait de sérum de lapins des anticorps anti-spermatozoïdes humains via la technique du sulfate d'ammonium saturé et en ayant recours à une librairie phagique de peptides (12-mer). Les clones positifs ont été identifiés par ELISA, séquencés à façon et les peptides correspondants ont été synthétisés. In fine, un test ELISA diagnostic a été conçu pour être utilisé avec des échantillons cliniques de sérum et de plasmas séminaux. RéSULTATS: Au total, soixante clones de phages ont été sélectionnés, et seize d'entre eux se sont avérés interagir avec les ACAS en ELISA indirect comme en ELISA sandwich. Les séquences peptidiques de ces seize clones positifs ont été obtenues. Par comparaison avec les bases de données (Blast), quatre de ces seize clones positifs se sont révélés être étroitement liés à la reproduction masculine. Deux des quatre mimotopes (#1 et #25) ont été synthétisés, et un test ELISA a été généré en utilisant ces deux mimotopes comme antigènes spécifiques des spermatozoïdes. Cent trente-quatre échantillons de sérum et soixante-quatorze échantillons de plasma séminal de patients de couples infertiles ont alors été analysés avec ce test ELISA. Respectivement, les échantillons sériques se sont révélés positifs à 20,15% (27/134) pour le mimotope #1 et à 11,19% (15/134) pour le mimotope #25, avec un taux de coïncidence de 91,04% (122/134). Seul un échantillon de plasma séminal (1/74, soit 1, 35%) s'est révélé positif à la fois pour le mimotope #1 et #25 (coïncidence 100%). CONCLUSION: La technique « phage display¼ nous a permis d'identifier des mimotopes d'antigènes spermatiques qui ont pu être utilisés afin de générer un test ELISA pour la détection d'anticorps anti-spermatozoïdes.
ABSTRACT
Nurses' work-related fatigue has been recognized as a threat to nurse health and patient safety. The aim of this study was to assess the prevalence of fatigue among first-line nurses combating with COVID-19 in Wuhan, China, and to analyze its influencing factors on fatigue. A multi-center, descriptive, cross-sectional design with a convenience sample was used. The statistical population consisted of the first-line nurses in 7 tertiary general hospitals from March 3, 2020 to March 10, 2020 in Wuhan of China. A total of 2667 samples from 2768 contacted participants completed the investgation, with a response rate of 96.35%. Social-demographic questionnaire, work-related questionnaire, Fatigue Scale-14, Generalized Anxiety Disorder-7, Patient Health Questionnaire-9, and Chinese Perceived Stress Scale were used to conduct online survey. The descriptive statistic of nurses' social-demographic characteristics was conducted, and the related variables of work, anxiety, depression, perceived stress and fatigue were analyzed by t-tests, nonparametric test and Pearson's correlation analysis. The significant factors which resulted in nurses' fatigue were further analyzed by multiple linear regression analysis. The median score for the first-line nurses' fatigue in Wuhan was 4 (2, 8). The median score of physical and mental fatigue of them was 3 (1, 6) and 1 (0, 3) respectively. According to the scoring criteria, 35.06% nurses (n=935) of all participants were in the fatigue status, their median score of fatigue was 10 (8, 11), and the median score of physical and mental fatigue of them was 7 (5, 8) and 3 (2, 4) respectively. Multiple linear regression analysis revealed the participants in the risk groups of anxiety, depression and perceived stress had higher scores on physical and mental fatigue and the statistically significant positive correlation was observed between the variables and nurses' fatigue, the frequency of exercise and nurses' fatigue had a statistically significant negative correlation, and average daily working hours had a significantly positive correlation with nurses' fatigue, and the frequency of weekly night shift had a low positive correlation with nurses' fatigue (P<0.01). There was a moderate level of fatigue among the first-line nurses fighting against COVID-19 pandemic in Wuhan, China. Government and health authorities need to formulate and take effective intervention strategies according to the relevant risk factors, and undertake preventive measures aimed at reducing health hazards due to increased work-related fatigue among first-line nurses, and to enhance their health status and provide a safe occupational environment worldwide. Promoting both medical and nursing safety while combating with the pandemic currently is warranted.