Objective To evaluate the relationship between pharmacodynamics of sufentanil-induced respiratory depression and age factors. Methods Forty ASA Ⅰ or Ⅱ patients scheduled for elective abdominal surgery were randomly divided into 2 groups according to the age: young and middle-aged group (25-64 yr, group M) and elderly group (65-80 yr, group E). EC50 was determined by up-and-down sequential trail. The initial target effect-site concentration (Ce) of sufentanil was set at 0.40 and 0.35 μg/ml in group M and E respectively.Each time Ce decreased/increased by 10% in the next patient depending on whether or not the respiratory depression occurred. Respiratory depression was defined as VT ≤ 5 ml/kg, RR ≤ 8 bpm/min, SpO2 ≤ 94%,PET CO2 ≥ 55 mm Hg, and/or apnea ≥ 15 s. Results The EC50 and 95 % confidence interval of sufentanil causing respiratory depression were 0.61 (0.54-0.70) μg/ml and 0.41 (0.38-0.45) μg/ml in group M and E respectively with the significant difference. Conclusion The efficacy of sufentanil-induced respiratory depression is related to age factors and the elderly patients are more sensitive to sufentanil-induced respiratory depression.

Objective To investigate the effects of different doses of dexmedetomidine on cerebral oxygen saturation and pulmonary shunt fraction in patients undergoing one-lung ventilation (OLV). Methods Sixty ASAⅠ-Ⅱpatients, aged 46-71 years, with body mass index (BMI)18-24 kg/m2 and scheduled for thoracotomy were randomly divided into three groups (n=20 each):high dose dexmedetomidine group (group D1), low dose dexmedetomidine group (group D2) and control group (group C). Dexmedetomidine 1μg/kg was infused in group D1 after anesthesia induction, and then a rate of 0.5μg·kg-1·h-1 was continuously infused. Dexmedetomidine 0.5μg/kg was infused in group D2 after anesthesia induction, and then a rate of 0.3μg · kg-1 · h-1 was continuously infused. Group C was received the equal volume of normal saline. Anesthesia was main?tained with propofol-remifentanil and intermittent iv boluses of rocuronium. Arterial and jugular venous blood samples were collected before anesthesia induction (T0), at 15 min after two-lung ventilation (T1), at 5 min (T2) and 30 min (T3) of OLV for blood gas analysis. Value of Qs/Qt was calculated and SctO2 was recorded at the same time. Results Compared with group C and group D2, Qs/Qt was decreased at T2 in group D1 (P<0.05). Qs/Qt was lower at T3 in group D1 and D2 than that of group C, and which was lower in group D1 than that of group D2 (P<0.05). In group C and group D1 a significant de?crease in SctO2 was observed at T2 and T3 compared to that at T0 and T1 (P<0.05). SctO2 was significantly higher at T2 and T3 in group D2 than that in group C and group D1 (P<0.05). Conclusion Dexmedetomidine given during OLV undergoing thoracotomy can improve oxygenation, decrease pulmonary shunt fraction and reduce the occurrence of low SctO2.

Objective:This study retrospectively analyzed an outbreak of dengue fever in Puyang of Henan province in 2019, in order to find the sources of infection.Methods:Dengue virus IgM/IgG and NS1 antigen were tested by colloidal gold method. E gene was amplified by PCR. MegaX was used for sequences alignment to construct evolutionary distance trees.Results:After clinical and laboratory confirmation, there were 81 cases of dengue fever, 17 of which were imported case who were local farmers and worked in Combadia and Thailand, and 64 of which were indigenous cases. The E gene alignment results showed that the pathogen of this epidemic was Vietnamese 1 and highly homologous with the Vietnamese strain. After the local outbreak, dengue virus E gene developed a nucleotide site mutation which can be steadily transmission.Conclusion:The dengue fever outbreak in Puyang was a local outbreak caused by dengue virus type 1, which was associated with imported cases. Gene sequencing showed that the imported pathogen had a relatively stable and transmissible nucleotide mutation after the local epidemic.

Objective:This study retrospectively analyzed an outbreak of dengue fever in Puyang of Henan province in 2019, in order to find the sources of infection.Methods:Dengue virus IgM/IgG and NS1 antigen were tested by colloidal gold method. E gene was amplified by PCR. MegaX was used for sequences alignment to construct evolutionary distance trees.Results:After clinical and laboratory confirmation, there were 81 cases of dengue fever, 17 of which were imported case who were local farmers and worked in Combadia and Thailand, and 64 of which were indigenous cases. The E gene alignment results showed that the pathogen of this epidemic was Vietnamese 1 and highly homologous with the Vietnamese strain. After the local outbreak, dengue virus E gene developed a nucleotide site mutation which can be steadily transmission.Conclusion:The dengue fever outbreak in Puyang was a local outbreak caused by dengue virus type 1, which was associated with imported cases. Gene sequencing showed that the imported pathogen had a relatively stable and transmissible nucleotide mutation after the local epidemic.

Coronavirus infection can cause serious respiratory and digestive system diseases in hu-mans and animals.In recent years,the frequent outbreaks and newly outbreaks of coronavirus in-fection have threatened global public health and the development of livestock and poultry.Howev-er,the development of anti-coronavirus drugs and vaccines was restricted due to the insufficient understanding of the mechanisms of coronavirus pathogenesis and cross species transmission.Re-verse genetic manipulation technology is a powerful tool in virological research,which can be used for the study of pathogenesis mechanisms,replication mechanisms and function analysis of protein.It is also be used in the development of attenuated or gene labeled vaccines,and antiviral drugs.Due to the large genome and complex structure of the coronavirus,the reverse genetic manipulation technology of coronavirus has been lagging for a long time.With the continuous updating of molec-ular biology methods,various new construction strategies have emerged.This article focuses on the construction strategy of the reverse genetic operating system for coronavirus,as well as its applica-tion in virus transmission and pathogenic mechanisms,and development of vaccines,which will provide favorable tools for the prevention and control of the coronavirus infection.