Physical activity among older Chinese adults living in urban and rural areas: A review

With an increase in rural-to-urban migration, a rapidly aging population, and the rising risk of developing noncommunicable diseases in China,it is important to understand the epidemiology of physical activity(PA) and health in the context of disease prevention and population health.Despite its public health importance, there is a significant lack of knowledge about PA in older Chinese adults that may hamper primary prevention efforts of health promotion in an increasingly aging population. To fill this gap, this article presents a narrative review of PA in the older Chinese adult population with a special focus on residential settings(i.e., urban and rural). Using existing studies, the review examines overall PA patterns and their correlates and discusses public health implications and future research. Although there are some preliminary indications of urban and rural differences in PA in the aging population in China, continued research efforts are needed to facilitate primary prevention efforts aimed at reducing noncommunicable diseases and promoting an active lifestyle among the largest population of older people in the world.

Comments to “Mechanism of hamstring muscle strain injury in sprinting”by Yu et al.

We have carefully read Dr.Yu and his colleagues'~1review on the mechanism of hamstring muscle strain injury in sprinting.There is no doubt that they have done a lot work in this field.Their views are based on 3 pieces of evidence.First,observations from in situ animal models suggest that muscle strain injuries are highly associated with eccentric contractions.Second,the magnitude of muscle strain,rather than the force。

The late swing and early stance of sprinting are most hazardous for hamstring injuries

Hamstring strain injury is one of most prevalent noncontact injuries in sports that involve high-speed running,such as sprinting,soccer,and rugby.~1In order to optimize prevention strategies and injury rehabilitation,studies have been conducted to understand hamstring function during sprinting.^(2–4)However,differences have long existed in the literature as to the cause of hamstring strain injuries.One of the most

The effect of aerobic dancing on physical fitness and cognitive function in older adults during the COVID-19 pandemic-a natural experiment

During the Coronavirus disease(COVID-19),the physical activity of older adults is at a lower level.The study aimed to examine the effectiveness of aerobic dancing on physical fitness and cognitive function in older adults.We conducted a randomized controlled trial with 34 older adults who were assigned into an aerobic dancing group and a control group.Three dance sessions weekly for 60min were scheduled for the aerobic dancing group for a total of 12 weeks.Physical fitness,blood pressure,lipids,glucose,cognitive function were assessed before and after the intervention.Baseline adjusted Analysis of Covariance(ANCOVA)was used to determine whether outcome variables varied between groups at pre-test and post-test.Effect size(Cohen's d)was calculated to determine the differences between groups from baseline to post-test.After 12 weeks,we found that the aerobic dancing group showed significant improvement in memory(portrait memory:F=10.45,p=0.003,d=1.18).The Limit of Stability(LOS)parameters in the aerobic dancing group displayed a significant increase after the intervention(right angle:F=5.90,p=0.022,d=0.60;right-anterior angle:F=4.23,p=0.049,d=0.12).Some beneficial effects were found on flexibility,grip strength,balance and subjective well-being(sit and reach:F=0.25,p=0.62,d=−0.40;grip strength:F=3.38,p=0.08,d=0.89;one-legged standing with eyes closed:F=1.26,p=0.27,d=0.50)in the aerobic dancing group.Aerobic dancing training was effective in improving memory and balance ability in older adults during the COVID-19 pandemic in China.In the future,aerobic dancing is a promising tool to encourage physical activity in older adults.

Simultaneous virus identification and characterization of severe unexplained pneumonia cases using a metagenomics sequencing technique

Many viruses can cause respiratory diseases in humans.Although great advances have been achieved in methods of diagnosis,it remains challenging to identify pathogens in unexplained pneumonia(UP) cases.In this study,we applied next-generation sequencing(NGS) technology and a metagenomic approach to detect and characterize respiratory viruses in UP cases from Guizhou Province,China.A total of 33 oropharyngeal swabs were obtained from hospitalized UP patients and subjected to NGS.An unbiased metagenomic analysis pipeline identified 13 virus species in 16 samples.Human rhinovirus C was the virus most frequently detected and was identified in seven samples.Human measles virus,adenovirus B 55 and coxsackievirus A10 were also identified.Metagenomic sequencing also provided virus genomic sequences,which enabled genotype characterization and phylogenetic analysis.For cases of multiple infection,metagenomic sequencing afforded information regarding the quantity of each virus in the sample,which could be used to evaluate each viruses' role in the disease.Our study highlights the potential of metagenomic sequencing for pathogen identification in UP cases.

Epidemiology and Genotypic Diversity of Eurasian Avian-Like H1N1 Swine Influenza Viruses in China

Eurasian avian-like H1 N1(EA H1 N1)swine influenza virus(SIV)outside European countries was first detected in Hong Kong Special Administrative Region(Hong Kong,SAR)of China in 2001.Afterwards,EA H1 N1 SIVs have become predominant in pig population in this country.However,the epidemiology and genotypic diversity of EA H1 N1 SIVs in China are still unknown.Here,we collected the EA H1 N1 SIVs sequences from China between 2001 and 2018 and analyzed the epidemic and phylogenic features,and key molecular markers of these EA H1 N1 SIVs.Our results showed that EA H1 N1 SIVs distributed in nineteen provinces/municipalities of China.After a long-time evolution and transmission,EA H1 N1 SIVs were continuously reassorted with other co-circulated influenza viruses,including 2009 pandemic H1 N1(A(H1 N1)pdm09),and triple reassortment H1 N2(TR H1 N2)influenza viruses,generated 11 genotypes.Genotype 3 and 5,both of which were the reassortments among EA H1 N1,A(H1 N1)pdm09 and TR H1 N2 viruses with different origins of M genes,have become predominant in pig population.Furthermore,key molecular signatures were identified in EA H1 N1 SIVs.Our study has drawn a genotypic diversity image of EA H1 N1 viruses,and could help to evaluate the potential risk of EA H1 N1 for pandemic preparedness and response.

Size-resolved effective density of submicron particles during summertime in the rural atmosphere of Beijing, China

Particle density is an important physical property of atmospheric particles.The information on high time-resolution size-resolved particle density is essential for understanding the atmospheric physical and chemical aging processes of aerosols particles.In the present study,a centrifugal particle mass analyzer(CPMA) combined with a differential mobility analyzer(DMA) was deployed to determine the size-resolved effective density of 50 to 350 nm particles at a rural site of Beijing during summer 2016.The measured particle effective densities decreased with increasing particle sizes and ranged from 1.43 to 1.55 g/cm^3,on average.The effective particle density distributions were dominated by a mode peaked at around 1.5 g/cm^3 for 50 to350 nm particles.Extra modes with peaks at 1.0,0.8,and 0.6 g/cm3 for 150,240,and 350 nm particles,which might be freshly emitted soot particles,were observed during intensive primary emissions episodes.The particle effective densities showed a diurnal variation pattern,with higher values during daytime.A case study showed that the effective density of Aitken mode particles during the new particle formation(NPF) event decreased considerably,indicating the significant contribution of organics to new particle growth.

The S190R mutation in the hemagglutinin protein of pandemic H1N1 2009 influenza virus increased its pathogenicity in mice

Human influenza viruses preferentially bind to sialic acid-α2,6-galactose (SAα2,6Gal) receptors, which are predominant in human upper respiratory epithelia, whereas avian influenza viruses preferentially bind to SAα2,3Gal receptors. However, variants with amino acid substitutions around the receptor-binding sites of the hemagglutinin (HA) protein can be selected after several passages of human influenza viruses from patients’ respiratory samples in the allantoic cavities of embryonated chicken eggs. In this study, we detected an egg-adapted HA S190R mutation in the pandemic H1N1 virus 2009 (pdmH1N1), and evaluated the effects of this mutation on receptor binding affinity and pathogenicity in mice. Our results revealed that residue 190 is located within the pocket structure of the receptor binding site. The single mutation to arginine at position 190 slightly increased the binding affinity of the virus to the avian receptor and decreased its binding to the long human α2,6-linked sialic acid receptor. Our study demonstrated that the S190R mutation resulted in earlier death and higher weight loss in mice compared with the wild-type virus. Higher viral titers at 1 dpi (days post infection) and diffuse damage at 4 dpi were observed in the lung tissues of mice infected with the mutant virus.

Epidemiological and Genetic Characteristics of the H3 Subtype Avian Influenza Viruses in China

Avian influenza viruses(AIVs)are naturally preserved in waterfowls and sometimes spill over to infect humans and mammalian animals.The H3 subtype is one of the most prevalent influenza virus subtypes in waterfowls.Since 2000,H3 subtype AIVs have been continuously isolated from poultry and wild birds in the mainland of China,which implied a dynamic spread in large-scale geography and multiple species.Combinations of H3 with N1–N8 subtypes were reported,among which H3N2 and H3N8 subtypes predominated.

Mutations associated with egg adaptation of influenza A(H1N1)pdm09 virus in laboratory based surveillance in China, 2009–2016

Mutations of influenza virus associated with adaptation occurring during passage in embryonated chicken eggs could result in antigenic change or reduced vaccine effectiveness.In this study,we investigated the mutations of influenza A(H1N1)pdm09 egg isolates from the Chinese National Influenza Surveillance Network between 2009 and 2016.Thirteen mutations were identified in the hemagglutinin(HA)protein from viruses passaged in eggs,in comparing to those in cells.After scanning public database,four mutations,D127E,L191I,D222G/N and Q223R in HA1,which may alter the receptor-binding specificity,were observed frequently.Although the A(H1N1)pdm09 virus has evolved in human for nearly ten years,most egg-cultured viruses acquired one or more further mutations.Using the egg isolates for influenza surveillance requires extra caution because of these selected mutations,and their impacts on antigenicity and receptor-binding property need further evaluation.Currently,most of the influenza vaccines are produced using egg isolates,particularly in China.Thus,there is an urge to promote the establishment of an alternative influenza vaccine production platform.

The substitution V379I in PA protein attenuates the pathogenicity of influenza A(H1N1)pdm09 viruses in mice

Dear Editor,Since August 2010,the world was in the post-pandemic period and the influenza A(H1N1)pdm09(pdmH1N1)virus co-circulated with H3N2 and B virus seasonally(WHO,2010).The continuous surveillance on the pdmH1N1 virus in the post-pandemic period was recommended by WHO.In order to detect unusual events that might indicate a shift in severity disease,or emergence of a new virus,we collected a total of 312 throat swabs of laboratory-confirmed pdmHlNl patients from Hunan and Jilin provinces in

Secondary organic aerosol formation from straw burning using an oxidation flow reactor

Herein,we use an oxidation flow reactor,Gothenburg:Potential Aerosol Mass(Go:PAM)reactor,to investigate the secondary organic aerosol(SOA)formation from wheat straw burning.Biomass burning emissions are exposed to high concentrations of hydroxyl radicals(OH)to simulate processes equivalent to atmospheric oxidation of 0-2.55 days.Primary volatile organic compounds(VOCs)were investigated,and particles were measured before and after the Go:PAM reactor.The influence of water content(i.e.5%and 11%)in wheat straw was also explored.Two burning stages,the flaming stage,and non-flaming stages,were identified.Primary particle emission factors(EFs)at a water content of 11%(~3.89 g/kg-fuel)are significantly higher than those at a water content of 5%(~2.26 g/kg-fuel)during the flaming stage.However,the water content showed no significant influence at the non-flaming stage.EFs of aromatics at a non-flaming stage(321.8±46.2 mg/kg-fuel)are larger than that at a flaming stage(130.9±37.1 mg/kg-fuel).The OA enhancement ratios increased with the increase in OH exposure at first and decreased with the additional increment of OH exposure.The maximum OA enhancement ratio is~12 during the non-flaming stages,which is much higher than~1.7 during the flaming stages.The mass spectrum of the primary wheat burning organic aerosols closely resembles that of resolved biomass burning organic aerosols(BBOA)based on measurements in ambient air.Our results show that large gap(0%-90%)still remains to estimate biomass burning SOA if only the oxidation of VOCs were included.