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The fall armyworm, Spodoptera frugiperda (Noctuidae: Lepidoptera), is a wide-reaching notorious insect pest of important cereal crops, which has developed resistance to multiple classes of insecticides. It invaded the Sichuan Province of China in 2019. In this study, we performed resistance monitoring of insecticides for 11 field-collected populations from Sichuan, and all the populations were susceptible to emamectin benzoate and chlorpyrifos. The variations in resistance level to indoxacarb (resistance ratio (RR), 9.23–45.53-fold), spinetoram (RR, 4.32–18.05-fold), and chlorantraniliprole (RR, 2.02–10.39-fold) were observed among these populations. To investigate the resistance mechanism of chlorantraniliprole, synergism tests were performed and showed that piperonyl butoxide had a slight synergistic effect on chlorantraniliprole for the QJ-20 population (1.43-fold) in moderate resistance (RR, 10.39-fold) compared with the treatment group without synergist. Furthermore, the expression scanning for resistance-related genes showed that five P450 genes (CYP6AE43, CYP321A8, CYP305A1, CYP49A1, and CYP306A1) and the ryanodine receptor gene (Ryr, chlorantraniliprole target) were overexpressed in the QJ-20 population. These results indicated that the fall armyworm in Sichuan has exhibited diverse susceptibilities to several classes of insecticides, and the overexpression of Ryr and several P450 genes may contribute to the development of resistance in S. frugiperda to chlorantraniliprole. [ABSTRACT FROM AUTHOR]

Objective: Since the outbreak of a highly contagious new pneumonia, atypical pneumonia or severe acute respiratory syndrome (SARS) occurred in Guangzhou area, 33 children with this syndrome were treated in the authors' hospital. The present study aimed to understand clinical characteristics and prognosis of pediatric SARS patients in Guangzhou area., Methods: Clinical manifestations, laboratory and radiologic findings, therapeutic approaches and prognosis of the 33 children with SARS in Guangzhou area were analyzed., Results: Of the 33 cases, 17 were males and 16 were females. The age was between 3 months to 13 years, and 3 - 12 years old patients accounted for 82%. Five (15%) cases had an evident history of contacting SARS patient before the symptoms occurred. Another 5 (15%) cases had a history that contacts of these patients (family members or friends) developed fever and/or cough later. The most common symptoms in this cohort were fever (100%) and cough (91%). Most of the cases had high fever, higher than 39 degrees C. Near half of the cases had nonproductive cough. The initial blood cells count showed that total white blood cell (WBC) count was (2.5 - 9.7) x 10(9)/L. In 22 (67%) cases the WBC count was < 5.0 x 10(9)/L, and in 10 (30%) WBC was (5.0 - 7.0) x 10(9)/L, in 18 cases most of the WBC were lymphocyte count. Chest radiograph showed patchy infiltrates, in 15 cases the changes were unilateral, and in 18 were bilateral. The radiologic changes developed fast, in some cases the changes progressed from one side to both sides. The opacity was absorbed slowly, significant absorption took in average two weeks. Elevated ALT was found in 3 cases and elevated CK-MB in 2 cases. Treatment included isolation, good ventilation of the ward, bed rest, supportive regimens, low volume oxygen inhalation, use of Chinese traditional medicine, antibiotics to prevent bacterial infection, and anti-inflammation therapy. All the patients recovered and discharged from hospital after a mean period of 10.0 +/- 3.8 days., Conclusion: SARS in children may have its own characteristics. The main clinical manifestations were high fever and cough while no severe toxic symptoms, nor respiratory failure was seen; few symptoms or signs suggesting involvement of systems other than respiratory system were seen. Chest radiograph showed uni- or bilateral asymmetric air-space infiltrates which could worsen quickly and were absorbed slowly. Though there were severe changes in the lung, the patients might not have corresponding symptoms or signs. The total white blood cell count in peripheral blood did not increase. All the patients studied had a favorable outcome after the combined treatment.