AIM　To observe the effect of intravenous injection of erythromycin (EM) on interdigestive migrating motor complex (MMC) and postprandial gastrointestinal contraction in conscious dogs , and to study its possible mechanism. METHODS　Gastrointestinal contractile activity was recorded using low compliance capillary water perfusion manometric system. EM was administered intravenously during phaseⅠ and after meal, and blood samples were drawn for measuring plasma motilin concentrations. RESULTS　①Plasma motilin levels showed cyclical fluctuations in different phases of MMC, and plasma motilin reached peak during phaseⅢ and lowest during phaseⅠ.②EM induced phaseⅢ-like contractions in the antrum and duodenum, which was not accompanied by a peak in plasma motilin level. The optimum dose of EM for resulting in a premature phaseⅢ with the same characteristics as the spontaneously occurring phaseⅢ was established to be 0.5 mg*kg-1. The dose of 10 mg*kg-1 EM induced gastrointestinal continuous contractions and duodeno-gastric retrograde peristalsis which was associated with retching and vomiting. ③Atropine obviously inhibited EM-induced phaseⅢ activity in the antrum and duodenum. ④EM powerfully enhanced postprandial gastrointestinal contractile activity. CONCLUSIONS The results suggests that EM is a potent prokinetic agent. The mechanism is not related to the release of motilin, but may be mediated partially by cholinergic pathway.

Objective To establish a one-step recombinase polymerase amplification (RPA) method for pathogen screening and rapid detection in the field targeting for five hemorrhagic fever related viruses (Zaire ebola virus, Sudan ebola virus, Marburg virus, Lassa virus and Yellow fever virus). Methods The specific nucleic acid (NA) fragments of each virus were selected as target genes by genome sequence analysis, and the primers and probes for RPA assays were designed according to the sequence. A series of diluted template genes were used for RPA detection to determine the sensitivity. The hemorrhagic fever-related viral nucleic acids were used for RPA detection to determine the specificity. The amplification experiments were carried out at different temperature ranging from 37℃ to 42℃ to validate the reaction temperature range. Results The RPA reaction systems of the five hemorrhagic fever viruses could effectively amplify the target genes, the sensitivities were between 1.5×102 and 1.5×103 copies. No cross reactions existed with the other hemorrhagic fever-related viral genes. Meanwhile, RPA assay could effectively amplify the target genes at 37-42℃. Conclusion The isothermal RPA assays of five hemorrhagic fever viruses are established, which may amply target genes fast and react at a wide temperature range, and be potentially useful for in field pathogens detection.

Objective To construct the pseudovirus containing nucleic acid(NA)fragments of Marburg virus,Zaire Ebola virus,Sudan Ebola virus,Lassa fever virus and Yellow fever virus by using a lentiviral vector system in order to provide a reference standard for the detection of the five viruses.Methods The gene fragments of the above five viruses were synthesized in vitro,connected into a single gene by fusion PCR technique,and cloned into lentiviral vectors with its auxiliary vector.After co-transfecting into 293T cells,the supernatants were collected on 48 h and 72 h post transfection. The naked NA was cleaned from the supernatants using DNase and RNase digestion before pseudotype virus was purified and concentrated.After the NA of the pseudotype virus,were extracted normal PCR and real-time PCR were conducted. Results Sequence analysis showed that the five target genes in vitro synthesis were properly connected and inserted into lentivirus vectors.Using the NA of the pseudotype virus as the template,both normal PCR and real-time PCR could sensitively amplify the target gene with the primers and probes of the above five,viruses respectively.The result indicated that the pseudovirus particles containing the five kinds of hemorrhagic fever virus target genes were successfully packaged. Conclusion The pseudovirus particles containing gene fragments of five viruses are constructed,which can be used as a common reference standard for NA detection.

AIM To observe the effect of intra- venous injection of erythromycin (EM) on interdigestive migrating motor complex (MMC) and postprandial gastrointestinal contraction in conscious dogs, and to study its possible mechanism. METHODS Gastrointestinal contractile activity was recorded using low compliance capillary water per fusion manometric system. EM was administered intravenously during phase I and after meal, and blood samples were drawn for measuring plasma motilin concentra- tions. RESULTS ①Plasma motilin levels showed cyclical fluctuations in different phases of MMC, and plasma motilin reached peak during phaseⅢ and lowest during phase Ｉ. ②EM induced phase Ⅲ -like contractions in the antrum and duodenum, which was not accompanied by a peak in plasma motilin level. The optimum dose of EM for resulting in a premature phaseⅢ with the same characteristics as the spontaneously occurring phaseⅢ was established to be 0. 5 mg.kg-1. The dose of 10 mg.kg-1 EM induced gas- trointestinal continuous contractions and duodeno-gas-tric retrograde peristalsis which was associated with retching and vomiting. ③Atropine obviously inhibited EM-induced phase Ⅲ activity in the antrum and duodenum. GEM powerfully enhanced postprandial gastrointestinal contractile activity. CONCLUSIONS The results suggests that EM is a potent prokinetic agent. The mechanism is not related to the release of motilin, but may be mediated partially by cholinergic pathway.

Objective:To analyze the correlation between chronic obstructive pulmonary disease (COPD) and cognitive dysfunction.Methods:This is a case-control study. From February 2022 to October 2022, 32 COPD patients (inpatient and outpatient) from the Department of Respiratory and Critical Care Medicine and Rehabilitation Medical Center of the First Affiliated Hospital of Nanjing Medical University and 32 healthy subjects were recruited. All participants underwent a thorough evaluation, which included Montreal Assessment of Cognitive Function (MoCA), visuospatial n-back task included accuracy (ACC) and mean response time (RT), the pulmonary functions including forced vital capacity (FVC), forced expiratory volume in the first second (FEV 1), one-second rate (FEV 1/FVC) and maximum volume per minute (MVV), Health Survey Short Form (SF-36), and St. George′s Respiratory Questionnaire (SGRQ). The correlation between cognitive dysfunction and lung function, SF-36 and SGRQ in COPD patients were analyzed. Results:The prevalence of smoking, hypertension and cardiovascular disease in the two groups were significantly different (all P<0.05). MoCA score, 1-back ACC and 2-back ACC in COPD group were significantly lower than those in healthy control group [(23.86±4.50) vs (27.55±1.29) points, (76.82%±16.60%) vs (90.61%±7.40%), (67.93%±10.10%) vs (78.74%±10.38%), all P<0.001]; 2-back RT was significantly higher than that of healthy group [(316.43±108.17) vs (254.09±101.62) ms, P<0.05]; and the Physiological function (PF), physiological function (RP), emotional function (RE), energy (VT), social function (SF), physical pain (BP) in SF-36 were significantly worse than the healthy control group (all P<0.05). The MoCA score of COPD group was positively correlated with FEV 1/FVC ( r=0.501, P=0.018). The 1-back ACC was positively correlated with FEV 1 and FEV 1/FVC ( r=0.568, 0.634; both P<0.05). The 1-back RT was negatively correlated with FEV 1/FVC and MVV ( r=-0.452, -0.534; both P<0.05). The 2-back ACC was positively correlated with FEV 1/FVC ( r=0.426, P=0.048). The 2-back RT was negatively correlated with MVV ( r=-0.571, P=0.006). In COPD group, MoCA score was negatively correlated with activity, influence and total score in SGRQ ( r=-0.533, -0.466, -0.521; all P<0.05). The 1-back ACC was negatively correlated with activity, influence and total score ( r=-0.552, -0.517, -0.584; all P<0.05). The 1-back RT was positively correlated with activity, influence and total score ( r=0.430, 0.379, 0.417; all P<0.05). The 2-back ACC was negatively correlated with impact and total score ( r=-0.398, -0.412; both P<0.05). Conclusion:COPD patients have impaired cognitive function, which is mainly manifested by the decline of working memory and executive function, and is correlated with the lung function, general health condition and quality of life.