Epidemiological and clinical features of children with mild coronavirus disease 2019 / 中国当代儿科杂志

OBJECTIVE@#To study the epidemiological and clinical features of children with mild coronavirus disease 2019 (COVID-19).@*METHODS@#The children who were diagnosed with mild COVID-19 in the Wuchang Shelter Hospital in Wuhan from February 5 to March 10, 2020 were enrolled as subjects. The clinical, laboratory, and lung imaging data were collected during hospitalization and isolation. This was a retrospective single-center case series analysis.@*RESULTS@#A total of 1 124 patients with mild COVID-19 were admitted from February 5 to March 10, 2020, including 13 children (1.16%). All the 13 children (7 boys and 6 girls) were residents of Wuhan in China, with a median age of 16 years (range: 10-18 years). Of all the 13 children, 9(69%) were from family clusters of COVID-19 and 4(31%) had unknown sources of infection. The mean time from exposure to onset was 6.8 days (range: 2-13 days) in 9 children with a definite history of exposure. There were 6 symptomatic children with the main manifestations of fever, cough, weakness, and myalgia, and the mean time from onset to hospitalization was 9.2 days. Of all the 13 children, 7(54%) were asymptomatic with positive nucleic acid test of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). There were 4 children (31%) with abnormal lung CT findings, mainly patchy shadows or ground-glass opacities in the lung field, and 6 children (46%) had no symptoms with normal lung CT findings. All children had normal routine blood test results and C-reactive protein levels. Eight children underwent SARS-CoV-2 IgM and IgG tests at least once, among whom 6 had negative SARS-CoV-2 IgM but positive IgG, and 2 underwent SARS-CoV-2 IgM and IgG tests twice and had negative results. Of all the 13 children, 11(85%) had negative results of two SARS-CoV-2 nucleic acid tests during hospitalization and were discharged, and 2(15%) had positive results of four SARS-CoV-2 nucleic acid tests and were transferred to another hospital and lost to follow-up. Among the 11 children who were followed up, 1 had positive results of two SARS-CoV-2 nucleic acid tests at the isolation point, and 10 had negative results. The mean hospital stay was 10.9 days for the 13 children. Eleven children recovered during follow-up, with good living and learning conditions.@*CONCLUSIONS@#Children with mild COVID-19 often have an uncertain history of exposure and may not have any clinical symptoms. Etiological diagnosis is more important than clinical diagnosis. The disappearance of clinical manifestations may not parallel with the result of SARS-CoV-2 nucleic acid test. SARS-CoV-2 has a long detoxification time, and there may be recurrent cases of SARS-CoV-2 positivity. Further studies are needed to investigate the production patterns of SARS-CoV-2 IgM and IgG and their effect on the body.

Roles of the public-facility-turned temporary hospital in prevention and control of coronavirus disease 2019 in Wuhan, China and clinical experience in the hospital / 中国当代儿科杂志

Since the outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, China, the public-facility-turned temporary hospital (PFTH) has played an important role in preventing the spread of the epidemic. Wuchang PFTH is the first one to put into clinical practice and the last one suspended in Wuhan. The National Emergency Medical Rescue Team of the Second Xiangya Hospital of Central South University, together with other 13 medical teams (841 medical staff in total), have fulfilled the task for the treatment of non-severe COVID-19 patients, without any medical staff infected. The first author of the article was the only pediatrician working in the Wuchang PFTH. The author describes and summarizes the features/functions, management/operations, and advantages/challenges of the PFTH, in order to provide reference for medical institutions and relevant departments to deal with public health emergencies.

The accuracy of puncture guided by intelligent positioning system using magnetic navigation / 中华医学超声杂志（电子版）

Objective To assess the accuracy of puncture guided by intelligent positioning (IP) system using magnetic navigation.Methods Five prepared targeted models at three certain depth (100 mm,large depth) underwent puncture guided by intelligent positioning system using IP and conventional ultrasound (US),respectively.Puncture errors,the number of attempt and spent time were recorded and compared .Results For the targets at small,medium and large depth,the errors of IP was (1.88 ±1.18),(1.56 ±0.56) and (3.99 ±1.10) cm,and the errors of conventional US was (4.52 ±2.23),(4.49 ±1.73) and (3.93 ±2.19) cm respectively.The errors of IP were significantly less than those of conventional US at small(t=-2.345,P=0.047) and medium(t=-3.608,P=0.007) depth,but there was no statistically significant difference at large depth (t=0.058,P=0.955). In the IP group,there were statistically significant differences for puncture errors between the small and large depth,as well as between medium and large depth ( F =8.923,P =0.010).There was no statistically significant difference for the errors of IP between the small and medium depth (t=-1.927,P=0.501).For the targets at small,medium and large depth,each puncture was performed in single attempt when guided by IP and in 2,1 and 2 attempt when guided by conventional US .At small and large depth,the numbers of attempt of IP were significantly less than those of conventional US (U=-2.372,P=0.018;U=-2.39, P=0.032).Whereas at medium depth,there was no significant difference (U=-1.000,P=0.690).For the targets at small,medium and large depth,each puncture spent (21.20 ±2.39)s, (27.00 ±4.00)s and (31.80 ±3.83)s when guided by IP,and(45.20 ±9.68),(26.80 ±4.21) and (54.60 ±13.48)s when guided by conventional US.The spent time of IP was less than that with conventional US for small and large depth targets(t =-5.383, P =0.001;t =-3.637, P =0.007).Whereas no statistically significant difference was found for the medium depth target (t=0.077,P=0.916).Conclusion In comparison with conventional US,IP system guided puncture is more accurate and the number of attempt and spent time is less .

Preconditioning of morphine protects rabbit myocardium from ischemia-reperfusion injury / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the protective effects of preconditioning morphine on rabbit myocardium during ischemia-reperfusion.</p><p><b>METHODS</b>Thirty New Zealand male white rabbits were randomly assigned to three groups: control, I/R and morphine groups. In morphine group 1.0 mg/kg morphine was given preoperationaly, in control and I/R groups 1.0 ml/kg NS was given. Twenty-four hours later rabbits in morphine and I/R groups underwent 40 min of coronary occlusion followed by 2 hours of reperfusion; for control group only sham operation was performed. At the end of the reperfusion, infarct size (IS) and area at risk (AAR) were defined by Evans blue and TTC staining. At the end of the reperfusion blood samples were taken for determination of plasma SOD activity and MDA levels. The heart was harvested and levels of the HSP27 were determined by Western blot, and the heart ultrastructures were observed under the electron microscopy.</p><p><b>RESULTS</b>Compared with I/R group,morphine significantly reduced infarct size (21.5%+/-2.4% Compared with 37.8%+/-1.7%, P<0.05). The morphine had a lower level of MDA and higher levels of SOD and HSP27 than those in I/R.</p><p><b>CONCLUSION</b>Preconditioning of morphine demonstrates cardioprotective effect on ischemia/reperfusion injury, which may be associated with increased HSP27 levels in the heart.</p>

Effect of morphine postconditioning on myocardial ischemia-reperfusion injury in rabbits / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the protective effects of morphine postconditioning on myocardial ischemia-reperfusion (I/R)injury and the potential mechanisms in rabbits.</p><p><b>METHODS</b>Thirty-two New Zealand male white rabbits were randomly assigned into 4 groups: Group 1 (Sham), Group 2 (I/R), Group 3 (ischemic postconditioning), Group 4 (ischemia and morphine postconditioning). Group 1 was perfused for 160 min; Group 2 underwent 40 min ischemia and 120 min reperfusion; Group 3 underwent three cycles of 30 s reperfusion and 30 s left anterior descending coronary artery re-occlusion immediately after 40 min ischemia and before 120 min reperfusion; Group 4 was given morphine 1.0 mg/kg immediately after 40 min ischemia in 1 min and before 120 min reperfusion. Blood samples were taken from arterial line at 20 min before occlusion, 20 min after occlusion, 40 min after occlusion, 1 h after reperfusion and 2 h after reperfusion for determination of the plasma levels of cardiac troponin I (cTnI). At the end of the reperfusion, infarct size (IS) and area at risk were defined by Evans and TTC staining. Plasma SOD activity and MDA were determined at the end of reperfusion.</p><p><b>RESULT</b>The levels of cTnI were significantly lower during reperfusion in the two postconditioning groups than those in I/R group. The plasma MDA content was significantly lower and SOD activity was significantly higher in the two postconditioning groups than those in I/R group, but there was no difference between two postconditioning groups. Morphine significantly reduced infarct size of the left ventricular area at risk as compared with I/R group (P<0.05).</p><p><b>CONCLUSION</b>Morphine postconditioning is as effective as ischemic postconditioning in the protection of myocardium against I/R injury in rabbits. Decrease in oxygen free radicals and increased antioxidant activity might be involved in its mechanism.</p>

Effect of ulinastain on the expression of hemeoxygenase-1 in oleic acid-induced acute lung injury in rats / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of ulinastain on the expression of hemeoxy genase-1 (HO-1) in oil acid-induced acute lung injury in rats.@*METHODS@#The animal model of acute lung injury was established by oil acid. Thirty SD rats were randomly divided into 3 groups: the blank control group (A), the acute lung injury group (B) and the acute lung injury group (C) followed by injecting 100 mL/kg ulinastatin. Each group consisted of 10 rats. Group A were given 0.2 mL/kg natural solution through the trial vein; Group B and C were given 0.2 mL/kg oil-acid through trial vein, while group C were injected 100mL/kg ulinastatin by the peritoneal cavity after injecting oil acid. After 4 hours, the rates of respiration were counted and blood samples were cramped out through the heart puncture for blood gas analysis. The expressions of hemeoxygenase-1 and the pathologic construction changes were determined by HE staining in the lower right lung of rats in the 3 groups.@*RESULTS@#The respiration dysfunction caused by oil acid could be prominently improved by ulinastain. There was only a little expression of hemeoxygenase-1 in the lung of Group A, but the expression increased in Group B and significatively increased in Group C.@*CONCLUSION@#Ulinastatin may protect the rats from acute lung injury through increasing the expression of HO-1.

Effect of morphine on dorsal horn projection neurons in neuropathic pain rats / 中南大学学报(医学版)

OBJECTIVE@#To explore the inhibitory effect of spinal topical morphine on the dorsal horn projection neurons in nerve-injured rats and its mechanism.@*METHODS@#Single-unit activity of dorsal horn projection neurons was recorded in anesthetized L(5)/L(6) nerve-ligated rats. Allodynia was determined by a behavior test in nerve-injured rats. The evoked neuronal responses to mechanical stimuli applied to the receptive field were determined before and after the spinal topical application of morphine, bicuculline plus morphine, strychnine plus morphine, and both bicuculline and strychnine plus morphine in normal, sham operation, and nerve-injured rats.@*RESULTS@#Spinal topical application of 10 micromol/L morphine significantly inhibited the evoked responses of dorsal horn projection neurons in normal, sham, operation and nerve-injured rats. However, the inhibitory effect of morphine was significantly reduced in nerve-injured rats compared with that in normal and sham operation rats. Furthermore, the topical application of 20 micromol/L bicuculline had little effect on the inhibitory effect of morphine in nerve-injured rats but it almost abolished the effect of morphine in normal and sham operation rats. The glycine receptor antagonist strychnine at 4 micromol/L significantly decreased the effect of morphine in nerve-injured, normal, and sham operation rats.@*CONCLUSION@#The loss of tonic GABAergic inhibition contributes to the reduced inhibitory effect of morphine on dorsal horn projection neurons in nerve-injured rats.