RESUMO
BackgroundMeasurement of SARS-CoV-2 antibody seropositivity is important to accurately understand exposure to infection and/or vaccination in specific populations. MethodsChildren with or without prior SARS-CoV-2 infections, was enrolled in Calgary, Canada in 2020. Venous blood was sampled 4 times from July 2020 to April 2022 for SARS-CoV-2 nucleocapsid and spike antibodies. Demographic and clinical information was obtained including SARS-CoV-2 testing results and vaccination records. Results1035 children were enrolled and 88.9% completed all 4 visits; median age 9 years (IQR: 5,13); 519 (50.1%) female; and 815 (78.7%) Caucasian. Before enrollment, 118 (11.4%) had confirmed or probable SARS-CoV-2. By April 2022, 39.5% of previously uninfected participants had a SARS-CoV-2 infection. Nucleocapsid antibody seropositivity declined to 16.4% after more than 200 days after diagnosis. Spike antibodies remained elevated in 93.6% of unvaccinated children after more than 200 days after diagnosis. By April 2022, 408 (95.6%) children 12 years and older had received 2 or more vaccine doses, and 241 (61.6%) 5 to 11 year-old children had received 2 vaccine doses. At that time, all 685 vaccinated children had spike antibodies, compared with 94/176 (53.4%) of unvaccinated children. ConclusionsIn our population, after the first peak of Omicron variant infections and introduction of COVID-19 vaccines for children, all vaccinated children had SARS-CoV-2 spike antibodies, in contrast to 53.4% of unvaccinated children. It is not yet known whether a high level of seropositivity at a point in time indicates sustained population-level protection against SARS-CoV-2 transmission or severe COVID-19 outcomes in children. SummaryBy April 2022, all vaccinated children with or without acquired SARS-CoV-2 infections had spike antibodies, compared with just over one-half of unvaccinated children. Its not known whether overall seropositivity level in a population indicates sustained protection against severe COVID-19 outcomes.
RESUMO
Objective To analyze the clinicopathologic data and operative parameters of 209 elderly co-lon cancer patients treated by radical resection between January 2002 and December 2011 ,and to investigate the factors related to recurrence and metastasis after colon cancer radical resection in elderly patients .Methods We used univariate and multivariate analysis of Cox regression ,including 14 variables:age,gender,disease duration, hospitalization duration,surgeon experience,operation duration,laparoscopicsurgery,tumor location,tumor size, gross morphology ,differentiate degree ,depth of bowel wall invasion ,lymph node involvement and obstruction .The survival curve was obtained by Kaplan -Meier method.Results Univariate analysis showed that tumor size (RR=2.658,P<0.0001),gross morphology(Infiltrating type,RR=3.407,P=0.0054),degree of differentiation (RR=0.32,P<0.0001) were associated with tumor relapse and metastasis .Multivariate analysis showed that gender(RR=0.585,P=0.0359),tumor size(RR=2.364,P<0.0001),degree of differentiation (Infiltrating type,RR=0.246,P=0.0437),gross morphology(RR=0.31,P<0.0001)were the significant factors.Conclu-sion Gender,tumor size,degree of differentiation,gross morphology were the independent factors of recurrence and metastasis of colon cancer after radical resection in elderly patients .Targeted follow -up for high -risk groups will improve patients′life quality and prolong their survival time .
