Anti-tumour effects by a trimodal combination of temozolomide,meloxicam and X-rays in cultures of human glioma cells

Purpose:?To investigate the possible cytotoxic interactions between the chemotherapeutic drug temozolomide (TMZ) and the cyclooxygenase-2 inhibitor meloxicam (MLC) or of both drugs combined with X-rays in three human glioma cell lines (D384, Hs 683 and U251).

Materials and methods:?Cells were exposed to TMZ (96 hours) and MLC was co-incubated during the last 24?h. Thereafter, cells were irradiated with X-rays and plated for a clonogenic assay. Total cell numbers and the numbers of surviving cells were determined to study the recovery of the cell populations (up until 19 days) following different combinations of TMZ, MLC and X-rays.

Results:?The combination of MLC and TMZ caused an enhanced cytotoxic effect in D384 and Hs 683. Various treatment combinations demonstrated significant radiation enhancement in all three cell lines. Long-term observations of D384 cells demonstrated that the repopulation rates of the surviving cells are far less affected by the various treatment protocols than those from the non-surviving cells.

Conclusions:?The present study demonstrates that a combination of TMZ and MLC resulted in a significant potentiation of their cytotoxicity in D384 and Hs683. The combination of these two drugs can also cause considerable enhancement of the radiation response in human glioma cell lines, although only D384 cells benefit from trimodal over bimodal treatment.     

Forensic performance of 30 InDels included in the Investigator DIPplex system in Miao population and comprehensive genetic relationship in China

Binary markers of insertion and deletion (InDel) play an important role in forensic personal identification, parentage testing, and individual ancestry inference. We first genotyped 30 InDels included in the Investigator DIPplex in 403 unrelated healthy Zunyi Miao people and analyzed the genetic polymorphisms, as well as explored the genetic relationship between Miao and 32 Chinese reference populations. No departures from the HWE were observed. The combined power of discrimination and the combined probability of exclusion were 0.99999999998 and 0.9884, respectively. Forensic parameters demonstrated that 30 markers are polymorphic and informative in the Zunyi Miao population and can be used as a tool for forensic personal identification and parentage testing. Allele frequency divergence analysis found that 12 out of 30 displaying high allele frequency difference between Turkic-speaking populations and other Chinese populations can be used as candidates of ancestry informative markers for ancestry inference of sub-population in East Asia. Population genetic parameters in the comprehensive population comparison among 33 Chinese populations indicated that our studied Hmong-Mien-speaking Miao has a close genetic relationship with geographically adjacent Enshi Tujia and genetically differentiate from Turkic-speaking populations.

     

Population data of 19 autosomal STR loci in the Li population from Hainan Province in southernmost China

In the present study, population data of 19 autosomal STR loci included in the Goldeneye™ DNA ID System 20A in 653 Li individuals was obtained and population genetic relationships among 13 populations were investigated. MDS and phylogenetic analysis suggested that the Hainan Li population kept a close genetic relationship with the Chinese Han populations, especially for Southern Han populations (Guangdong Han, Sichuan Han, and Hunan Han). Our results indicated that the 19 autosomal STRs are highly discriminative and polymorphic in the Hainan Li population suitable for personal forensic identification and paternity testing.

     

Forensic parameters of 19 X-STR polymorphisms in two Chinese populations

Application of X-STRs as complements of autosomal STR application in the forensic genetics has become a tendency for kinship testing, especially in deficiency paternity cases. Recently, a novel kit of 19 X-STR loci was developed, which permitted the analysis of 19 STR in the same PCR reaction, and these markers can be clustered into seven groups for the physical linkage. The objective of this study was to evaluate the allele and haplotype diversity of 19 X-STR loci in the Uygur (n = 220) and Tibetan nationality (n = 270) and to estimate the usefulness for complex kinship analysis. In the Tibetan and Uygur populations, a total of alleles of all loci were 188 and 212, with the allele frequencies ranged from 0.0037 to 0.5593 and from 0.0045 to 0.5409, respectively. Compared with previous studies, DXS10135 was the most polymorphic locus in the two population groups, whereas the least variant locus was DXS10164 in the Uygur population and DXS7423 in the Tibetan nationality. Haplotype diversity obtained in this investigation was greater than 0.9 across all LGs. This study indicated the new kit could be used as a supplementary tool in kinship testing in China. In addition, the data sets can be used as supplementary national X-STR references to enlarge the database.

     

Cancer risks in a population with prolonged low dose-rate γ-radiation exposure in radiocontaminated buildings, 1983 – 2002

Purpose: To assess cancer risks in a population that received prolonged low dose-rate γ-irradiation for about 10 years as a result of occupying buildings containing ⁶⁰Co-contaminated steel in Taiwan.

Materials and methods: The cancer risks were compared with those populations with the same temporal and geographic characteristics in Taiwan by standardized incidence ratios (SIR), adjusted for age and gender. The association of cancer risks with excess cumulative exposure was further evaluated for their relative risks by the Poisson multiple regression analysis.

Result: A total of 7271 people were registered as the exposed population, with 101,560 person-years at risk. The average excess cumulative exposure was approximately 47.8 mSv (range < 1 – 2,363 mSv). A total of 141 exposed subjects with various cancers were observed, while 95 developed leukemia or solid cancers after more than 2 or 10 years initial residence in contaminated buildings respectively. The SIR were significantly higher for all leukemia except chronic lymphocytic leukemia (n = 6, SIR = 3.6, 95% confidence interval [CI] 1.2 – 7.4) in men, and marginally significant for thyroid cancers (n = 6, SIR = 2.6, 95% CI 1.0 – 5.7) in women. On the other hand, all cancers combined, all solid cancers combined were shown to exhibit significant exposure-dependent increased risks in individuals with the initial exposure before the age of 30, but not beyond this age.

Conclusions: The results suggest that prolonged low dose-rate radiation exposure appeared to increase risks of developing certain cancers in specific subgroups of this population in Taiwan.     

Phylogenetic analysis among 27 Chinese populations and genetic polymorphisms of 20 autosomal STR loci in a Chinese Uyghur ethnic minority group

Allele frequency data and forensic statistical parameters were determined for 20 autosomal short tandem repeat (STR) loci of the PowerPlex 21 System in 214 unrelated healthy individuals of a Uyghur ethnic minority group living in Xinjiang province, northwest China. A total of 232 alleles were observed with the corresponding allele frequencies ranging from 0.0023 to 0.5304. All loci were consistent with Hardy–Weinberg equilibrium (HWE) after the Bonferroni correction (p > 0.0025). The combined probability of exclusion, power of discrimination, probability of matching value were 0.999999999, 0.9999999999999999999999995, and 4.78246 × 10^?25, respectively. Our results revealed that the 20 STRs were highly polymorphic and informative, and could be suitable for forensic application, especially parentage test and personal identification. The further population comparison between the Uyghur and other 26 reference populations revealed that the loci of D13S317, TH01 and D6S1043 showed high ethnical specificity. Phylogenetic analysis based on 19 shared loci demonstrated that the Uyghur had a close genetic relationship with the Kazakh, but a distinct genetic distance with other Chinese populations from different ethnicity and regions.     

Bias in the proportionate mortality ratio analysis of small study populations: A case on analyses of radiation and mesothelioma

Abstract

Purpose: To quantify bias in the proportionate mortality ratio (PMR) analysis of small study populations and develop a bias correction methodology.

Materials and methods: Bias in the PMR analysis of small study populations is quantified through algebraic derivation. A simulation procedure is developed to evaluate the relationship between bias and study population size. A recently published PMR analysis of radiation and mesothelioma among 329 deceased registrants in the United States Transuranium and Uranium Registries (USTUR) is used as an illustrated example.

Results: The proportionate mortality ratios are biased and overestimated in small population studies; the smaller the study population, the larger the overestimation. As such, the average overestimation of PMR for mesothelioma in the analyses of radiation and mesothelioma in USTUR is 7.2% (95% confidence interval = 5.1%, 9.7%); the PMR overestimation is 22.5% (95% confidence interval = 16.8%, 29.1%) when stratified by quartiles of radiation doses.

Conclusions: The degree of PMR small sample bias is mainly determined by the sample size ratio, which is defined as the ratio of the sample size to the number of disease categories in the reference population. Correction for the bias is recommended when the sample size ratio is less than 5. The quantification and correction algorithm of the PMR small sample bias developed in this research supplements the PMR methodology.     

Population genetics,diversity, forensic characteristics of four Chinese populations inferred from X-chromosomal short tandem repeats

We genotyped 19 X-STRs included in the AGCU X19 kit in 712 unrelated Chinese individuals from four populations (Li, Hui, Tibetan, and Han) and then merged with 4156 previously genotyped subjects from 19 populations to investigate genetic relationships and population structure, as well as the association between the genetic affinity and language classification. The combined mean paternity exclusion chances and the combined probabilities of discrimination based on single allele frequencies of 19-X-STRs and haplotype frequencies of seven linkage groups were high, indicating that this set of markers was very polymorphic in the four populations studied. Therefore, this panel can complement autosomal or uniparental markers in kinship analysis and complex deficient paternity testing. Subsequently, population differentiation analyses among 23 populations based on 19 STRs and 15 populations based on over 62 million single nucleotide polymorphisms consistently demonstrated that genetic stratifications exist between the different language-speaking populations, especially Tibeto-Burman-speaking, Tungusic and Turkic-speaking populations. Our newly studied populations are genetically close to ethnolinguistically adjacent populations. Our datasets can and should be used as an allele and haplotype frequencies reference database to facilitate the use of 19-X-STRs panel in routine forensic practice.     

How physical activity,diet, and sedentary behavior cluster according to age in adolescents?

Background

Clusters’ behaviors can change with age, moving from adolescence to adulthood.

Aims

This study examined physical activity (PA), diet, and sedentary behavior (SB) clusters according to age groups (11–12, 13–15, 16–17, and 18–19 years) and its association with sex and maternal education.

Methods

Brazilian National School-based Health Survey (PeNSE 2015) (n?=?16,522) data were analysed. Adolescents responded PA; consumption of fruits, vegetables; snacks, salt, and beverages (SSB); and SB. Two-step cluster analysis and Rao-Scott Chi square test were used.

Results

The Actives; the All-day sitters; the Inactive 1 (with moderate consumption of F&V); and the Inactive 2 (with small consumption of F&V and SSB) clusters were identified. The Actives and All-day sitters existed in all age groups. The Inactive 1 were the cluster more prevalent in 11–12 (33.9%), 13–15 (42.5%) and 16–17 (43.8%) age groups while, All-day sitters were most prevalent in 18–19 (43.7%) age group. Boys were more likely to be in the Actives; as against girls in All-day sitters, Inactive 1 and 2 clusters. The Actives had a higher proportion of adolescents with low maternal education.

Conclusions

SB increase in clusters over the increase of age group; else, adolescents in Actives groups decreased.

     

Comparison between X-ray-hysterosalpingography and 3 Tesla magnetic resonance-hysterosalpingography in the assessment of the tubal patency in the cause of female infertility

Objectives

XR-hysterosalpingography currently represents the gold standard for tubal pathology evaluation. Magnetic resonance-HSG is an innovative technique. With our study, we aim to comprehend if and how MR-HSG, compared to traditional XR-HSG, could give us this additional information in the diagnostic/therapeutic process.

Materials and methods

This study included 19 patients between 30 and 42 years old (average age 37.7) affected by infertility. Patients underwent contextually both XR-HSG and MR-HSG, using a single catheterization. The dynamic MR-HSG exam consisted a MR sequence during contrast administration through the cervical catheter.

Results

Both XR-HSG and MR-HSG documented that 15 of the 19 patients had bilateral tubal patency, while four patients had monolateral tubal patency. However, MR-HSG allowed us to diagnose additional findings:

• Two active endometriosis foci in adnexal localization and a condition of adenomyosis

• A unicornuate uterus malformation

• A submucous uterine myoma near the tubal ostium

• A decrease of the ovarian reserve in a patient

So MR-HSG could potentially detect in 10/19 (52%) women the cause of their infertility, compared to 4/19 (21%) detected with XR-HSG and about 30% of women would have resulted as false negatives if we only used XR-HSG.

Finally, with a questionnaire, we demonstrated that MR-HSG is less painful than XR-HSG.

Conclusions

These data thus confirm that XR-HSG and MR-HSG present the same diagnostic of assessing tubal patency. We also demonstrated that MR-HSG is able to detect further collateral findings that could likewise be a possible therapeutic target and it could possibly become the new gold standard in female infertility diagnostics.

     

Allele frequencies of 17 autosomal STR loci in the Va ethnic minority from Yunnan Province,Southwest China

Allele frequencies and forensic parameters for 17 autosomal short tandem repeat (STR) loci were investigated from 1542 individuals of Va ethnic minority in Yunnan Province in the southwest of China. Also, genetic distances between Va and 13 published populations were compared, and a neighbor-joining (NJ) phylogenetic tree was developed and visualized using averaged F _ST matrix. Results demonstrate that these loci are highly polymorphic in the Va population and can be applied in forensic, population genetic, and linguistic fields.

     

Genetic instability induced by low doses of x-rays in hamster cells

Purpose:?Genomic instability involves time delayed events and can be manifested as elevated rates of heritable changes in the progeny of irradiated cells. To study the induction of chromosomal instability by very low doses of radiation Chinese Hamster Ovary (CHO) cells were exposed to 10 – 50 milisieverts (mSv) (≈10 – 50 miligrays (mGy)) of x-rays.

Materials and methods:?Control and irradiated cell populations were assayed for chromosomal aberrations and assessed using a micronucleus test and anaphase-telophase analysis at the first cell division post-irradiation and at every four population doublings thereafter up to 16 population doublings post-irradiation.

Results:?Frequencies of micronuclei, anaphase-telophase alterations and chromosomal aberrations were increased when the cells were analysed immediately after x-ray exposure. Micronuclei and anaphase-telophase alterations showed significantly increased frequencies when they were analysed at 12 and 16 population doublings after exposure to 50 mSv. Chromosomal aberrations increased significantly at 12 and 16 population doublings after exposure to 10 mSv and 50 mSv.

Conclusions:?Our results are consistent with the presence of a phenomenon by which the initial DNA damage in the surviving cells is memorized. Micronuclei and achromatic lessions were the main cytogenetic damage observed in cells exposed to very low doses of x-rays, indicating that these low doses are able to induce genetic instability.     

Radioresistance of sibling Drosophila species from Laguna Verde,Veracruz, México

Purpose: To identify and quantify if the generation of electricity by nuclear power plants produces an increase in background radiation that might affect the radioresistance of organisms that live in that area.

Materials and methods: Natural populations of two sibling species of Drosophila, D. melanogaster and D. simulans, living in the immediate vicinity of the Mexican Nuclear Power Plant in Laguna Verde were studied for 10 years. Collections of flies were made at two sites, one close to and one further from two reactors, during both the pre‐operational and operational stages of the reactors. The effect of exposure to various doses of gamma‐rays on egg‐to‐adult survival of the flies was analysed.

Results: The data obtained indicate that in both sites, egg‐to‐adult survival was higher in D. melanogaster than in D. simulans. There was an increase in the egg‐to‐adult survival during the pre‐operational period of one of the reactors and the possible causes are discussed. No differences were found between the two sites.

Conclusions: The analysis indicates that the reactors do not have a negative impact on the Drosophila populations studied.     

Haplotype analysis of the polymorphic 24 Y-STR markers in six ethnic populations from China

Twenty-four Y-STR loci were analysed in 1446 males from the following six Chinese ethnic populations: Guangxi Han (n=600), Gin (n=161), Maonan (n=135), Miao (n=186), Zhuang (n=226) and Yao (n=138) using the AGCU Y24 STR amplification kit. The lowest estimates of genetic diversity (below 0.5) correspond to markers DYS391 (0.4006), DYS438 (0.4300), and DS388 (0.4907), and the greatest diversity corresponds to markers DYS385a/b (0.9636) and DYS527a/b (0.9439). Moreover, there were 1331 different haplotypes identified from the 1446 total samples, of which 1233 were unique. Notably, we observed shared haplotypes between the four ethnic populations (Maonan, Miao, Zhuang, Yao ethnic population), except between the Guangxi Han and Gin population. The estimated overall haplotype diversity (HD) was 0.9997. A multidimensional scaling (MDS) plot based on the genetic distances between populations demonstrates the genetic similarity of the Maonan, Miao and Zhuang populations with genetic distance below 3.0. No substructure correction is required to estimate the rarity of a haplotype comprising 24 markers. In summary, the results of our study indicate that the 24 Y-STRs have a high level of polymorphism in these six Chinese ethnic populations and could therefore be a powerful tool for forensic applications and population genetic studies.     

Biomechanical characteristics of slashing attack on different body parts of a dummy using a kitchen knife

Background

Slashing attack is one of the most common ways of committing a homicide. The purpose of this study was to evaluate the biomechanical characteristics of slashing different body parts of a dummy by young males and females using a Chinese kitchen knife and thus provide scientific evidence for criminal investigations and court trials.

Methods

A total of 12 male and 12 female college students participated in this study. Biomechanical parameters, including joint velocity, slashing velocity, slashing force, energy, and impulse, were evaluated when slashing the chest and the neck of a dummy using a Chinese kitchen knife.

Results

When slashing the neck or the chest of a dummy, male participants showed higher elbow and wrist velocities (21.2% and 28.5%, respectively) as well as higher knife velocity (33.6%), slashing velocity (25.3%), slashing force (23.3%), and energy (57.6%) compared to female participants (all p < 0.05). When slashing the chest, participants showed higher shoulder, elbow, and wrist velocities (31.9%, 12.7%, and 12.6%) as well as knife velocity (3.8%), slashing velocity (7.3%), and energy (23.2%) compared to slashing the neck (all p < 0.05), regardless of gender.

Conclusion

Both gender and slashing position have great impact on biomechanical characteristics of the slashing movement. Our data indicate that when slashing using a Chinese kitchen knife, males may induce severer wounds than females, and slashing different body parts may generate different slashing velocity or energy. Compared to slashing position, gender may have greater influence on the biomechanical characteristics. Findings from this study may expand our knowledge about knife slashing attacks by Chinese kitchen knives as well as other knives with comparative heavy blades.

     

Genetic polymorphism investigation of 16 X-STR loci in the Bai ethnic minority in Yunnan Province,Southwest China

To investigate the genetic variation and forensic efficiency of 16 X-chromosomal short tandem repeat (X-STR) loci (DX6795, DXS9902, DXS8378, HPRTB, GATA165B12, DXS7132, DXS7424, DXS6807, DXS6803, GATA172D05, DXS6800, DXS10134, GATA31E08, DXS10159, DXS6789, and DXS6810) in the Bai minority, we calculated allele frequencies, forensic parameters, and haplotype frequencies in 424 (202 males and 222 females) unrelated, healthy Bai individuals from Dali Bai Autonomous Prefecture in Yunnan Province, China. We observed a total of 132 alleles; 5–19 alleles were detected in each locus, and the corresponding allele frequencies ranged from 0.0016 to 0.7589. All of the loci detected were highly polymorphic in the Bai population in Yunnan Province, except DXS6800. The values for the combined power of discrimination in females (PDf) and males (PDm) were 0.999999999999996 and 0.999999997487061, respectively. According to a phylogenetic tree, neighboring populations and different nationalities in the same area appeared to have relatively close evolutionary relationships. This study provides and complements X-chromosome genetic polymorphism data for the Bai people in Yunnan Province, Southwest China, and enriches the available reference materials for this Chinese minority population.

     

Oral contraceptives provide protection against anterior cruciate ligament tears: a national database study of 165,748 female patients

ABSTRACT

Objective: Anterior cruciate ligament (ACL) tears are more prevalent in females than males. One of the factors responsible for this may be the variation in levels of estrogen and progesterone. The purpose of this study was to determine the potentially protective effects of oral contraceptive pills (OCPs) on ACL tears.

Methods: The PearlDiver database (www.pearldiverinc.com, Fort Wayne, IN) was queried for all OCP users amongst females aged 15–49. Female experiencing an ACL tear and undergoing surgery (CPT 29,888) were compared to a control group of females undergoing surgery for an ACL tear, but not on OCPs. Chi-squared testing was used to assess for significant differences in the rate of ACL reconstruction for the OCP and non-OCP users, according to age groups broken down into age intervals of 5 years.

Results: There were a total 82,874 patients in both the OCP and non-OCP groups. There was a total of 569 (0.69%) ACL reconstructions in the non-OCP group and 465 (0.56%) in the OCP group (p < 0.001). In the non-OCP group, patients aged 15–19 accounted for 29.35% of all ACL reconstructions, whereas, in the OCP group, this same age group only accounted for 13.33%. Among all age groups, the odds ratios for experiencing an ACL reconstruction while on OCP was 0.82 (χ² = 0.001, 95% CI 0.72–0.92) compared to not using OCP. This protective effect was driven primarily by the 15–19 age group (odds ratio 0.37 (χ² < 0.001, 95% CI 0.27–0.50)). The number need to treat for OCP usage in the 15–19 age group was six patients.

Conclusions: OCPs have a protective effect on ACL tear, especially in the 15–19 age group, which exhibited a 63% reduction in the rate of tear. Consideration should be given to prescribing OCPs to younger athletes, after careful assessment of the risks of these commonly prescribed medications.

Level of evidence: III     

Population genetic analyses and evaluation of 22 autosomal STRs in Indian populations

The allele frequencies and forensically relevant parameters for the 22 autosomal short tandem repeats (STRs) present in PowerPlex® Fusion (Promega, Madison, WI) were determined for 357 unrelated individuals from 11 states across India. The combined power of discrimination and probability of exclusion were 0.99999999999999999999999999875 and 0.999999997200846, respectively. The panel was found to be informative for Indian populations and generated a total of 275 alleles. Further, analyses with these loci did not show any noticeable clustering among the Indian populations.

     

Effects of peritoneal lavage fluid from radiation or/and burn injured rats on the growth of hematopoietic progenitor cells

Purpose:?To evaluate the effects of peritoneal lavage fluids from radiation injury, burn injury and combined radiation-burn injury on the growth of hematopoietic progenitor cells (HPC).

Materials and methods:?Rats were divided into four groups: A radiation group (RG), a burn group (BG), a combined radiation-burn group (CRBG) and normal control group (NG). RG and CRBG rats were irradiated with 12 Gy, and burns of 30% total body surface area were generated in group BG and group CRBG. Peritoneal lavage fluids were collected and tested for their effects on the growth of erythrocyte progenitor cells or granulocyte-macrophage progenitor cells of BALB/c mice in vitro.

Results:?The numbers of colony forming units-erythroid (CFU-E), burst forming units-erythroid (BFU-E) and colony-forming units-granulocyte-macrophage (CFU-GM) formed after treatment with lavage fluids from BG or CRBG were significantly higher than those from NG. However, fewer CFU-E, BFU-E or CFU-GM colonies were found after treatment with lavage fluid from the RG. In lavage fluid from BG and CRBG, the concentration of interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor α (TNFα) was increased in comparison to NG and RG. Treatment with these cytokines had similar promoting effects on the growth of hematopoietic colonies and neutralizing antibodies inhibited these effects significantly.

Conclusions:?Burns increase the responsiveness of the system and help the proliferation of hematipoietic progenitor cells, while radiation decreases all these responses relative to both the controls and the burn plus radiation group.     

COVID-19 pandemic impacts physical activity levels and sedentary time but not sleep quality in young badminton athletes

Purpose

Regular physical activity is a good strategy to maintain the health of athletes, and prevent pain and decreased joint flexibility during the pandemic. On the other hand, higher sedentary time during the pandemic period can have deleterious effects. The objective of this study was to compare physical activity levels, sedentary time, and sleep parameters during the pre-COVID period and the COVID-19 pandemic period in young badminton athletes.

Methods

Fifteen young badminton athletes were evaluated during a pre-COVID period (July 2019) and during the COVID-19 period (July 2020). Sleep parameters, physical activity level, and sedentary time were measured using a tri-axial accelerometer. Participants wore the accelerometer on their dominant wrist for 7 days consecutively. In addition, the average of each sleep parameter [time in bed and total sleep time in hours per day, sleep efficiency (%), wake after sleep onset (WASO, total per day), and sleep latency (minutes per day)] was reported over the 7-day period.

Results

Athletes presented increased sedentary time (pre-COVID?=?7.0?±?1.1 vs.COVID-19?=?8.9?±?1.9 h/day, p?=?0.004, d?=?1.30) and significant decreases in the total PA observed in counts per day (pre-COVID?=?2,967,064.4?±?671,544.1 vs. COVID-19?=?1,868,210.2?±?449,768.4 counts/day, p?=?0.001, d?=?1.99), time in vigorous PA (pre-COVID?=?7.7?±?0.9 vs. COVID-19?=?6.1?±?1.2 h/day, p?=?0.001, d?=?1.56), and time in moderate-to-vigorous PA (pre-COVID?=?8.1?±?0.9 vs. COVID-19?=?6.5?±?1.3 h/day, p?=?0.001, d?=?1.48). There were no significant differences for time in light and moderate PA or in sleep parameters (p?>?0.05).

Conclusion

Young badminton athletes presented increased sedentary time, and decreased total physical activity, time in MVPA, and time in vigorous activities during the COVID-19 pandemic compared to the pre-COVID period, however, there were no significant differences in sleep parameters.