Objective:To investigate the effect of virus inactivation on weak positive result of 2019 novel coronavirus(2019-nCoV) nucleic acid test.Methods:A retrospective study was conducted on the nasopharyngeal swabs of three patients with positive PCR nucleic acid test for 2019-nCoV at different concentrations in the Second affiliated Hospital of Zhejiang University Medical College from January to February 2020.The virus in nasopharyngeal swab specimens were inactivated by water bath at 56 ℃ for 30 min, dry bath at 56 ℃ for 60 min and dry bath at 60 ℃ for 30 min respectively. After treatment, these samples RNA were extracted and then detected by three new commercial quantitative real-time polymerase chain reaction reagent kits for 2019-nCoV.Cycle threshold (Ct) value was used to evaluate the effect of virus inactivation on nucleic acid detection of 2019-nCoV.Results:There was no significant difference between the groups before and after inactivation. Ct values of ORF1ab gene before inactivation were 23.28±0.28, 25.25±0.25, 28.93±0.44, 32.06±0.47, 35.20±0.38, 32.89±0.38, 36.24±0.23, 33.30±0.46, and those after inactivation were, group 1:23.60±0.20, 27.29±0.30, 31.83±0.51, 37.41±0.46, group 2: 24.25±0.34, 27.18±0.42, 31.84±0.61, 34.99±1.01, 34.89±0.45,group 3: 23.37±0.17, 26.89±0.52, 32.05±0.50.Ct value of N gene before inactivation were 24.38±0.09, 26.64±0.11, 30.35±0.12, 33.29±0.33, 36.93±0.11, 34.50±0.12, 35.63±0.12, those after inactivation were, group 1: 24.66±0.11, 28.52±0.14, 32.71±0.14, 37.00±0.13;group 2: 25.41±0.10, 28.79±0.15, 33.29±0.28; group 3: 23.37±0.11, 28.68±0.11, 33.54±0.13, 37.18±0.23(ORF1ab gene: t=-1.416; N gene: t=-1.379, P>0.05). There was no significant difference among the three inactivation groups, the specific Ct values are shown above(ORF1ab gene: t=-0.460; N gene: t=-0.132, P>0.05). However, the Ct values of the inactivated groups (1,2,3) and the non-inactivated group at different dilution times were different (10 ×:Ct value of ORF1ab was 25.25±0.25 in the non-inactivated group, and 27.29±0.30, 27.18±0.42 and 26.89±0.52 in the inactivated group1,2 and 3, t(ORF1ab)=-7.327, P<0.01.Ct value of N gene in the non-inactivated group was26.64±0.11, those in inactivated group 1, 2 and 3 were 28.52±0.14, 28.79±0.15 and 28.68±0.11, respectively, t (N)=-19.340, P<0.01. 100 ×:Ct value of ORF1ab was 28.93±0.44 in the non-inactivated group, and 31.83±0.51,31.84±0.61 and 32.05±0.50 in the inactivated group1,2 and 3, t (ORF1ab)=-9.462, P<0.01. Ct value of N gene in the non-inactivated group was 30.35±0.12, those in the inactivated group 1, 2 and 3 were 32.71±0.14, 33.29±0.28 and 33.54±0.13, respectively, t (N)=-18.583, P<0.01. The positive detection rate of the non-inactivated group (7/11, 8/11, 5/11) was significantly different from that of the inactivated group (inactivated group 1:4/11, 4/11, 3/11, inactivated group 2:3/11, 3/11, 3/11, and inactivated group 3:3/11, 3/11, 2/11) ( Z=-2.670, P<0.01). There were no significant difference among the inactivated groups(inactivated group 1:4/11, 4/11, 3/11, inactivated group 2:3/11, 3/11, 3/11, inactivated group 3:3/11, 3/11, 2/11) ( Z=4.413, P>0.05) and among the three reagents(reagent 1:7/11, 4/11, 3/11, 3/11, reagent 2:8/11, 4/11, 3/11, 3/11, reagent 3:5/11, 3/11, 3/11, 2/11)(χ 2=1.199, P>0.05). Conclusion:The virus inactivation can degrade the nucleic acid of the 2019-nCoV, resulting in the decrease of the Ct value and the false negative results of the low-concentration specimens.

Objective:To understand the viral genomic characteristics of a 2019-novel coronavirus (2019-nCoV) strain in the first COVID-19 patient found in Hangzhou, China.Methods:Viral RNA was extracted in throat swab and sputum sample of the patient and was performed real-time reverse transcription PCR detection and obtained viral genome by high-throughput sequencing method. Phylogenetic analysis was conducted using 29 2019-nCoV genomes and 30 β-coronavirus genomes deposited in NCBI GenBank. Fifteen genomes from Wuhan were grouped by mutation sites and others were identified by Wuhan's or specific mutation sites.Results:A 29 833 bp length genome of the first 2019-nCoV strain in Hangzhou was obtained, covering full length of the coding regions of coronavirus. Phylogenetic analysis showed that the genome was closest to the genome of a bat SARS-like coronavirus strain RaTG13 with an identity of 96.11% (28 666/29 826). Among the genes between two genomes, E genes were highly conserved (99.56%), while S genes had lowest identity (92.87%). The genome sequence similarities among 29 strains from China (Hangzhou, Wuhan, and Shenzhen), Japan, USA, and Finland, were all more than 99.9%; however, some single nucleotide polymorphisms were identified in some strains.Conclusion:The genome of Hangzhou 2019-nCoV strain was very close to the genomes of strains from other cities in China and overseas collected at early epidemic phase. The 2019-nCoV genome sequencing method used in this paper provides an useful tool for monitoring variation of viral genes.

Objective:To understand the viral genomic characteristics of a 2019-novel coronavirus (2019-nCoV) strain in the first COVID-19 patient found in Hangzhou, China.Methods:Viral RNA was extracted in throat swab and sputum sample of the patient and was performed real-time reverse transcription PCR detection and obtained viral genome by high-throughput sequencing method. Phylogenetic analysis was conducted using 29 2019-nCoV genomes and 30 β-coronavirus genomes deposited in NCBI GenBank. Fifteen genomes from Wuhan were grouped by mutation sites and others were identified by Wuhan's or specific mutation sites.Results:A 29 833 bp length genome of the first 2019-nCoV strain in Hangzhou was obtained, covering full length of the coding regions of coronavirus. Phylogenetic analysis showed that the genome was closest to the genome of a bat SARS-like coronavirus strain RaTG13 with an identity of 96.11% (28 666/29 826). Among the genes between two genomes, E genes were highly conserved (99.56%), while S genes had lowest identity (92.87%). The genome sequence similarities among 29 strains from China (Hangzhou, Wuhan, and Shenzhen), Japan, USA, and Finland, were all more than 99.9%; however, some single nucleotide polymorphisms were identified in some strains.Conclusion:The genome of Hangzhou 2019-nCoV strain was very close to the genomes of strains from other cities in China and overseas collected at early epidemic phase. The 2019-nCoV genome sequencing method used in this paper provides an useful tool for monitoring variation of viral genes.

Objective To analyze the prevalence of influenza A (H3N2) virus in Hangzhou be-tween 2012 and 2017 and to investigate the genetic variations in hemagglutinin ( HA) and neuraminidase ( NA) . -ethods Throat swab samples were collected for viral isolation from 12185 patients with suspected influenza in Hangzhou area from January 2012 to December 2017. Influenza virus subtypes were identified by real-time RT-PCR. HA and NA genes of some isolated Influenza A (H3N2) viruses were amplified with spe-cific primers and then analyzed by sequencing and phylogenetic analysis. Results Influenza A (H3N2) virus was the predominant subtype circulating in Hangzhou during 2012 to 2017. It caused high morbidity in elderly people (Z=81. 039, P<0. 05). Most of the isolated influenza A (H3N2) viruses belonged to the phylogenetic clades of 3C. 3a and 3C. 2a. These viruses shared a homology of 96. 7％-100％ in nucleotide sequences of both HA and NA genes, but possessed several HA and NA mutations in antigenic sites. Con-clusions Influenza A (H3N2) virus was an important pathogen causing influenza epidemics in Hangzhou during 2012 to 2017. HA and NA genes showed many mutations in antigenic sites. No drug resistant virus was reported.

Objective To investigate the characteristics of metabolic foci on 18F-fluorodeoxyglucose (FDG) PET/CT scan in pediatric patients with epilepsy.Methods Twenty-three pediatric patients (15 males,8 females,age range:0.5-13.3 years) with epilepsy were retrospectively reviewed from March 2014 to December 2016.All patients underwent 18F-FDG PET/CT and metabolic foci were found.The visual method and semi-quantitative analysis were used to analyze images.Fourteen of them underwent surgery and were followed up for 3-24 months.Results Glucose hypermetabolism were observed most frequently in the frontal and parietal lobes,with or without surrounding/remote hypometabolism.On the day of PET/CT imaging,8 patients had no seizures,14 patients had seizures,and 1 patient was uncertain.The sites of resection were consistent with the regions of hypermetabolism in 9 patients,among whom the pathological results showed 8 cortical malformations and 1 Rasmussen's syndrome.Follow-up results for the above 9 patients showed that there was 7 Engel class Ⅰ patients and 2 Engel class Ⅲ patients.Conclusion The hypermetabolism may mostly appear in the frontal and parietal lobes of pediatric patients with epilepsy,and malformations of cortical development seem to be the most common pathology results.

Objective To observe the metabolic changes of subcortical structures in children with intractable epilepsy using 18 F-FDG PET/CT,and to investigate the mechanism of subcortical structure involvement in epileptic seizures and its clinical significance.Methods Features of 18F-FDG PET/CT imaging in 611 intractable epilepsy children were analyzed.The metabolic changes of cortex and subcortical structures (basal ganglia,thalamus and cerebellum) were observed.The children were divided into three groups (young,middle and older groups) according to age,also mild group and severe group according to the number of involved lobar,respectively.The incidence of metabolic abnormalities in subcortical structures of different groups were analyzed.Results Among 611 children,unilateral cortical metabolic abnormality was found in 525,and bilateral cortical metabolic abnormalities were found in 86 children.The involvement of subcortical structures was detected in 190 children,including basal ganglia (n=64),thalamus (n=113) and cerebellum (n=105).The incidence of metabolic abnormality in subcortical structures under different age groups was not statistically different (all P＞ 0.05),while the incidence of metabolic abnormality in subcortical structures of severe group was significantly higher than that of mild group (all P＜0.001).Conclusion 18 F-FDG PET/CT might be able to detect the metabolic abnormalities of subcortical structures,therefore indicating the involvement of cerebral cortex.

PURPOSE: Caffeine is the most widely consumed psychostimulant. It is often adopted as a tool to modulate brain activations in fMRI studies. However, its pharmaceutical effect on task-induced deactivation has not been fully examined in fMRI. Therefore, the purpose of this study was to examine the effect of caffeine on both activation and deactivation under sustained attention. MATERIALS AND METHODS: Task fMRI was acquired from 26 caffeine naive healthy volunteers before and after taking caffeine pill (200 mg). RESULTS: Statistical analysis showed an increase in cognition-load dependent task activation but a decrease in load dependent de-activation after caffeine ingestion. Increase of attention and memory task activation and its load-dependence suggest a beneficial effect of caffeine on the brain even though it has no overt behavior improvement. The reduction of deactivation by caffeine and its load-dependence indicate reduced facilitation from task-negative networks. CONCLUSION: Caffeine affects brain activity in a load-dependent manner accompanied by a disassociation between task-positive network and task-negative network.
Brain ; Caffeine* ; Eating* ; Healthy Volunteers ; Magnetic Resonance Imaging ; Memory ; Memory, Short-Term*

Objective To investigate the clinical value of 18 F?FDG PET/CT in staging multiple myeloma ( MM) and evaluating the glucose metabolic activity of MM. Methods A total of 25 MM patients ( 13 males, 12 females, age:39-67 years) from May 2010 to April 2015 were enrolled in this retrospective study. The SUVmax of each patient was recorded. D?S plus staging according to 18 F?FDG PET/CT was com?pared with the traditional D?S staging. The SUVmax and the percentage of plasmacytes of bone marrow of phase Ⅲ and non?phase Ⅲ ( phaseⅠand Ⅱ) according to D?S plus staging were compared. Two?sample t test and Wilcoxon rank sum test were used to analyze the data. Results In 25 MM patients, the range of SUVmax of lesions was 1.8-12?0 and the mean value was 5.15±2.74. According to D?S staging, the numbers of patients with phase Ⅰ,Ⅱ andⅢwere 7, 4 and 14, respectively. While the numbers were 3, 1 and 21 by D?S plus staging. Based on the D?S plus staging system, stages of 7 patients ( 28%, 7/25 ) were changed. According to the D?S plus staging system, the SUVmax between phaseⅢand non?phaseⅢpatients was significantly different (5.75±2.54 vs 3.00±0?70; t=2.12, P<0.05), while the percentage of plasma?cytes of bone marrow between the 2 groups had no significant difference ( 17. 50%( 4. 25%-41. 75%) vs 11?15%(10.25%-36.57%);z=0.05, P>0.05). Conclusion 18F?FDG PET/CT is of clinical importance for MM staging and metabolic activity assessment of MM.

Objective To investigate the levels of blood pressure, blood lipid, blood glucose, body mass index (BMI) as well as the epidemiological characteristics of dyslipidemia, hyperglycemia, hypertension and metabolic syndrome of Hangzhou citizens. Methods A total of 28 990 citizens in Hangzhou city who underwent health checkup were recruited in this study, including 10 179 males and 18 811 females. The average age of subjects was 65.05 years. Subjects were asked to complete questionnaires regarding personal characteristics. The physical examination emphasized measurement of height, waist and blood pressure. Blood samples were collected and subjected to serum glucose, TC, HDL-C, LDL-C and TG measurements. The values of the examinations was described as xˉ± s . The ratios were compared with chi-square test. The trend analysis was conducted by linear correlation test. Results The prevalence of hypertension and metabolic syndrome was 17.1% and 11.2% respectively. And the prevalence of overweight/obesity and hyperglycemia was 36.3%,8.1%,16.4%respectively. It was indicated that the men had higher prevalence of hyperglycemia, hypertension, metabolic syndrome and overweight compared with women. However, as to the dyslipidemia, men and women were totally different. Women were more prone to suffer from hypercholesterolemia and elevation of low-density lipoprotein cholesterol. Men were apt to suffer from hypertriglyceridemia and reduction of high-density lipoprotein cholesterol. Divided the subjects by age into three groups, it was suggested that the rates of dyslipidemia, hyperglycemia, hypertension and overweight/obesity increased along with the increment of age in women. Although the rates of metabolic disorders were higher in the group of men, the trend of increase with age was not as significant as in women. It could be seen in men that dyslipidemia and overweight/obesity were reduced with the increase of age. Conclusion The metabolic disorders in Hangzhou citizens showed their own characteristics. It is suggested that multiple strategies targeting at different sexes and age-groups should be formulated to prevent and control the occurrence of metabolic diseases.