Diagnostic performance between CT and initial real-time RT-PCR for clinically suspected 2019 coronavirus disease (COVID-19) patients outside Wuhan, China.

INTRODUCTION: Chest CT is thought to be sensitive but less specific in diagnosing the 2019 coronavirus disease (COVID-19). The diagnostic value of CT is unclear. We aimed to compare the performance of CT and initial RT-PCR for clinically suspected COVID-19 patients outside the epicentre-Wuhan, China. MATERIALS AND METHODS: Patients clinically suspected of COVID-19 infection who underwent initial RT-PCR and chest CT at the same time were retrospectively enrolled. Two radiologists with specific training reviewed the CT images independently and final diagnoses of the presence or absence of COVID-19 was reached by consensus. With serial RT-PCR as reference standard, the performance of initial RT-PCR and chest CT was analysed. A strategy of combining initial RT-PCR and chest CT was analysed to study the additional benefit. RESULTS: 82 patients admitted to hospital between Jan 10, 2020 to Feb 28, 2020 were enrolled. 34 COVID-19 and 48 non-COVID-19 patients were identified by serial RT-PCR. The sensitivity, specificity was 79% (27/34) and 100% (48/48) for initial RT-PCR and 77% (26/34) and 96% (46/48) for chest CT. The image readers had a good interobserver agreement with Cohen's kappa of 0.69. No statistical difference was found in the diagnostic performance between initial RT-PCR and chest CT. The comprehensive strategy had a higher sensitivity of 94% (32/34). CONCLUSIONS: Initial RT-PCR and chest CT had comparable diagnostic performance in identification of suspected COVID-19 patients outside the epidemic center. To compensate potential risk of false-negative PCR, chest CT should be applied for clinically suspected patients with negative initial RT-PCR.

[Suitability assessment of construction land in the central and southern parts of Hebei Province, China based on potential-limitation model].

The suitability assessment of regional construction land is one of the important prerequisites for the spatial arrangement in regional planning, and also, the important foundation for the reasonable utilization of regional land resources. With the support of GIS, and by using the regional comprehensive strength and spatial accessibility analysis and the eco-environmental sensitivity analysis, this paper quantitatively analyzed the development potential and its ecological limitation of the central and southern parts of Hebei Province. Besides, based on the cost-benefit analysis, the potential-limitation model was accordingly developed, and the three land suitability scenarios under different developmental concepts were captured through the interaction matrix. The results indicated that both the comprehensive strength and the development potential of the study area showed a primacy distribution pattern, and presented an obvious pole-axis spatial pattern. The areas with higher eco-environmental sensitivity were mainly distributed in the west regions, while those with lower eco-environmental sensitivity were in the east regions. Regional economic development concept had important effects on the regional ecological security pattern and urban growth. The newly developed principles and methods for the land suitability assessment in this paper could not only scientifically realize the spatial grid of regional development potential and capture the future land development trend and spatial distribution, but also provide scientific basis and effective ways for urban and regional planning to realize region 'smart growth' and 'smart conservation'.

[Effect of peritoneal lavage with povine-iodine on prevention of postoperative sepsis after exposure of peritoneal cavity to sea water in rat].

OBJECTIVE: To observe the effects of peritoneal lavage with povine-iodine on prevention of sepsis after exposure of peritoneal cavity to sea water in rat. METHODS: Eighty-four SD rats were randomly divided into two groups, and the peritoneal cavity was exposed to sea water. Rats in group A were not treated (group A, n=42), and the peritoneal cavity was lavage with povine-iodine in group B (n=42). Plasma levels of endotoxin and tumor necrosis factor (TNF) were measured preimmersion, and 0, 12, 24 hours after seawater immersion (n=6), and positive incidence of blood bacterial culture was performed (n=18 in each group) in groups A and B. RESULTS: 1. Plasma levels of endotoxin and TNF in group A and B were increased significantly after exposure of peritoneal cavity to sea water (compared with baseline values, all P<0.05). Plasma levels of endotoxin and TNF in group B became lower than those in group A from 12 hours after seawater immersion (P<0.05 or P<0.01). 2. Positive incidence of bacterial culture in group B was 16.7 % (3/18) and it was lower than that in group A (77.8 % (14/18), P<0.01). CONCLUSION: Povine-iodine lavage in the peritoneal cavity can reduce levels of plasma endotoxin and TNF, and lower positive incidence of bacterial culture in rats after exposure of peritoneal cavity to sea water, thereby preventing the development of postoperative sepremia.

[Effect of hypotonic liquid containing colloid on hemorrhagic dogs with celiac seawater immersion wound].

OBJECTIVE: To determine hypotonic liquid containing colloid on hemorrhagic dogs with celiac seawater immersion wound. METHODS: Thirty-five dogs were randomly divided into five groups: control group (group A), 0.9% NaCl therapy group (group B) and 0.45% NaCl therapy group (group C), 5% glucose therapy group(group D) and hypotonic liquid containing colloid therapy group (group E). Changes of mean artery pressure (MAP), cardiac output (CO), urine volume, plasma osmotic pressure and pathologic changes of lung and brain were observed. RESULTS: hypotonic liquid containing colloid could effectively ameliorate MAP and CO, improve urine volume, decrease plasma osmotic pressure and prevent occurrence of lung and brain edema. CONCLUSION: Hypotonic liquid containing colloid can exert satisfactory therapeutic effects on hemorrhagic dogs with celiac seawater immersion wound.