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Three-dimensional (3D) tumor microspheres can simulate the interaction and growth dynamics of tumor cells, and have been used as a new in vitro model for drug screening and tumor biology related research. The scaffold-free culture of 3D tumor microspheres on microfluidic chips has many advantages, including low cost, high throughput, convenience and flexibility. However, it is still unclear how various factors, such as chip structure, influence the culture effect of tumor microspheres. The lack of standardized evaluation and characterization of the culture effect hinders the further optimization and development of chip function. This study presents numerical simulations of multiple parts or processes of the proposed 3D culture chips with two different structural parameters based on computational fluid dynamics (CFD) methods. An evaluation system for tumor microspheres was established. The prediction of the CFD simulation was consistent with the culture results of the chips, reflecting the important role of the structural parameters of the microtrap in the formation of uniform tumor microspheres. Furthermore, the velocity of cell suspension also had a significant impact on the retention of tumor cells. Additionally, the drug screening results of tumor microspheres indicated that tumor microspheres exhibit greater drug resistance, which may be attributed to their size. These results offer valuable insights into the factors that influence the characteristics of tumor microspheres. This research provides a reference and direction for the optimal design and functional evaluation of scaffold-free 3D culture chips, and holds promise for promoting the development of novel drug research platforms.

High-throughput drug screening (HTDS) has significantly reduced the time and cost of new drug development. Nonetheless, contact-dependent cell-cell communication (CDCCC) may impact the chemosensitivity of tumour cells. There is a pressing need for low-cost single-cell HTDS platforms, alongside a deep comprehension of the mechanisms by which CDCCC affects drug efficacy, to fully unveil the efficacy of anticancer drugs. In this study, we develop a microfluidic chip for single-cell HTDS and evaluate the molecular mechanisms impacted by CDCCC using quantitative mass spectrometry-based proteomics. The chip achieves high-quality drug mixing and single-cell capture, with single-cell drug screening results on the chip showing consistency with those on the 96-well plates under varying concentration gradients. Through quantitative proteomic analysis, we deduce that the absence of CDCCC in single tumour cells can enhance their chemoresistance potential, but simultaneously subject them to stronger proliferation inhibition. Additionally, pathway enrichment analysis suggests that CDCCC could impact several signalling pathways in tumour single cells that regulate vital biological processes such as tumour proliferation, adhesion, and invasion. These results offer valuable insights into the potential connection between CDCCC and the chemosensitivity of tumour cells. This research paves the way for the development of single-cell HTDC platforms and holds the promise of advancing tumour personalized treatment strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Environmental exposures during pregnancy have been associated with adverse obstetric outcomes. However, limited and inconsistent evidence exists regarding the association between air temperature exposure and the risk of preeclampsia (PE). This study aimed to evaluate the correlation between ambient temperature exposure during pregnancy and PE risk, as well as identify the specific time window of temperature exposure that increases PE risk. A population-based cohort study was conducted from January 2012 to April 2022 in Guangzhou, China. Pregnant women were recruited in early pregnancy and followed until delivery. A total of 3,314 PE patients and 114,201 normal pregnancies were included. Ambient temperature exposures at different gestational weeks were recorded for each participant. Logistic regression models were used to evaluate the correlation between ambient temperature exposure and PE risk. Stratified analyses were conducted based on maternal age and pre-pregnancy BMI. Distributed lag models were employed to identify the time window of temperature exposure related to PE. Exposure to extreme high temperature (aOR = 1.24, 95 % CI 1.12-1.38) and moderate high temperature (aOR = 1.22, 95 % CI 1.10-1.35) during early pregnancy was associated with an increased risk of PE. Furthermore, women with higher pre-pregnancy BMI had a higher risk of developing PE when exposed to high temperature during early pregnancy compared to normal-weight women. The time window of temperature exposure related to PE was identified as pregnancy weeks 1 to 8. This study provides evidence for the association of high temperature exposure during early pregnancy with the risk of PE, as well as identifies the specific time window of temperature exposure related to PE. These findings have implications for developing potential strategies to protect pregnant women, particularly those with higher pre-pregnancy BMI, from the adverse effects of extreme temperatures during early pregnancy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: The aim of the study was to conduct a comprehensive performance evaluation of the Mindray CX-9000 fully automated coagulation analyzer for the detection of the seven coagulation items., Methods: The performance of activated partial thromboplastin time (APTT), prothrombin time (PT), fibrinogen (FIB), thrombin time (TT), D-dimer (D-D), fibrinogen degradation product (FDP), and antithrombin Ⅲ (AT) was validated for precision, linear range, carryover contamination rate, reference interval validation, inter-method agreement, and anti-interference ability., Results: The intra- and inter-precision (coefficient of variation, CV%) of all seven items was less than the target CV%; the carryover contamination rates for different concentrations and between items were < 10%. The slope of the linear regression equation for the theoretical and measured values of the linear range was within 1 ± 0.05 and R ≥ 0.975. The reference interval quoted from the manufacturer's reference interval passed ≥ 95%. The CX-9000 was compared with the results of the reference instrument STAGO R MAX (STA-R MAX) and the p-values for all items ranged from 0.822 to 0.987. Within the concentration range claimed by the manufacturer, the interference errors produced by all items met the manufacturer's claimed criteria, except for triglycerides which produced interference errors > 10% for the FIB, D-D, FDP, and bilirubin which produced interference errors for the FIB and D-D assays., Conclusions: The CX-9000 automatic coagulation analyzer has good stability and repeatability, a wide linear range of detection, low carryover contamination rate, and high resistance to interference, making it suitable for the testing of clinical specimens.

The COVID-19 pandemic has forced governments around the globe to apply various preventive measures for public health. One of the most effective measures is wearing face masks, which plays a vital role in blocking the transmission of droplets and aerosols. To understand the protective mechanism of face masks, especially in indoor environments, we apply a computational fluid dynamics technique to predict the lifetime of cough droplets. Therefore, we can assess the exposure risk in a ventilated room where an infected individual wears a face mask or not. We focus on the dynamic evaporation and diffusion of droplets in a human-cough process, which is a major cause for the spread of the virus. We find that wearing a face mask can effectively reduce the total mass and Sauter mean diameter of the residual droplets after a single cough. The mass concentration of virus-carrying droplets in the ventilated room decreases by 201, 43,786, and 307,060 times, corresponding to wearing cotton face masks, surgical face masks, and N95 face masks, respectively. However, the maximum travel distance of 80% droplets is insensitive to wearing a face mask or not. Therefore, the residual droplets are widely distributed due to the influence of indoor airflow. Furthermore, we study aerosol exposure risks in different areas of the room and find that high concentrations of aerosols occur in the streamline through an infected individual, especially next to the individual within 1.5 m. This strongly suggests a social distance despite the fact that the majority of droplets are filtered by face masks. This study explains the impact of face masks and airflow on indoor exposure risks and further inspires potential measures for public health, for example, no individuals should sit near the air supply opening., (© 2022. The Author(s).)

Background: During the COVID-19 pandemic, China adopted a home isolation policy, which caused lifestyle changes for university students, including increased smartphone use. Several studies indicate that problematic smartphone use is associated with anxiety. However, this association has not been examined in the context of epidemics. The aim of this study was to investigate whether the duration of smartphone use was associated with anxiety in Chinese university students during the COVID-19 pandemic. Methods: Participants included 9716 university students (5458 men and 4258 women) from Liaoning, China. We assessed the duration of smartphone use with a self-reported questionnaire. Anxiety was assessed using the generalized anxiety disorder seven-item scale. A multivariate logistic regression analysis was performed to determine the adjusted association between smartphone use and anxiety. Results: After adjusting for confounding factors, we observed a positive association between smartphone use duration and the prevalence of anxiety in all participating students. Compared with short periods of smartphone usage, the odds ratios (95% confidence interval) for moderate and long smartphone usage duration were 1.17 (1.00, 1.36) and 1.58 (1.36, 1.83), respectively. This significant positive association did not change in the sex-stratified analysis (for both men and women). Conclusions: Our examination of the association between duration of smartphone uses and university students' anxiety levels revealed that long smartphone use was associated with a high prevalence of anxiety during the COVID-19 pandemic.

Diet is an important factor affecting intestinal microbiota in horses. Fecal microbiota is commonly used as a substitute for studying hindgut microbiota when investigating the relationship between intestinal microbial changes and host health. So far, no study has compared the difference between the fecal microbiota found in horses that are fed pasture grass, silage, and hay. The present study aims to characterize the fecal microbiota in horses that were exclusively on one of the three forage diets, and to analyze the potential impact of these forages, especially silage, on horse intestinal health. There were 36 horses randomly assigned to each of the three groups; each group was fed only one type of forage for 8 weeks. High throughput sequencing was applied to analyze the bacterial taxa in fecal samples collected from the horses at the end of the feeding trial. The Lachnospiraceae family was statistically more abundant in horses fed with hay, while it was the least abundant in horses fed with silage. The Streptococcaceae spp., considered a core microbial component in equine intestinal microbiota, were present in significantly lower quantities in feces from horses that were fed pasture grass as compared to those from horses fed hay or silage. The novel data may help promote the balancing of horse intestinal microbiota and the maintenance of intestinal health in horses.

Streptococcus equi subsp. equi ( S. equi ) is the pathogen causing strangles, a highly infectious disease that can affect equids including donkeys of all ages. It can persistently colonize the upper respiratory tract of animals asymptomatically for years, which serves as a source of infection. Several strangles outbreaks have been reported in the donkey industry in China in the last few years and pose a great threat to health, production, and the welfare of donkeys. Nasopharyngeal swab samples for culture and PCR are used widely in strangles diagnosis. Additionally, microbiomes within and on the body are essential to host homoeostasis and health. Therefore, the microbiome of the equid nasopharynx may provide insights into the health of the upper respiratory tract in animals. There has been no study investigating the nasopharyngeal microbiome in healthy donkeys, nor in donkeys shedding S. equi . This study aimed to compare nasopharyngeal microbiomes in healthy and carrier donkeys using 16S rRNA gene sequencing. Nasopharyngeal samples were obtained from 16 donkeys recovered from strangles (group S) and 14 healthy donkeys with no history of strangles exposure (group H). Of those sampled, 7 donkeys were determined to be carriers with positive PCR and culture results in group S. In group H, all 14 donkeys were considered free of strangles based on the history of negative exposure, negative results of PCR and culture. Samples from these 21 donkeys were used for microbial analysis. The nasopharyngeal microbiome composition was compared between the two groups. At the phylum level, relative abundance of Proteobacteria was predominantly higher in the S. equi carrier donkeys than in healthy donkeys ( P < 0.01), while Firmicutes and Actinobacteria were significantly less abundant in the S. equi carrier donkeys than in healthy donkeys ( P < 0.05). At the genus level, Nicoletella was detected in the upper respiratory tract of donkeys for the first time and dominated in carrier donkeys. It is suspected to suppress other normal flora of URT microbiota including Streptococcus spp., Staphylococcus spp., and Corynebacterium spp. We concluded that the nasopharyngeal microbiome in S. equi carrier donkeys still exhibited microbial dysbiosis, which might predispose them to other airway diseases., Competing Interests: TW and ZD were employed by the company Dong-E-E-Jiao Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zhu, Chen, Yi, Holyoak, Wang, Ding and Li.)

Purpose: Poor eating behaviors are associated with imbalances in energy and food intake, which may directly or indirectly contribute to muscle strength loss. This study aimed to investigate the association between eating behaviors and hand grip strength in Chinese adults., Materials and Methods: We designed and conducted a cross-sectional study of 2009 Chinese individuals aged 25-65 years in 2017. Eating behaviors, including breakfast consumption, snacking after dinner, and eating rate, were assessed using a self-administered questionnaire. Hand grip strength was assessed using a digital grip dynamometer. Age, sex, BMI, physical activity, educational level, occupation, living status, sleep duration, smoking and drinking status, hypertension, diabetes, and depressive symptoms were used as confounding factors., Results: After final adjustments for confounding factors, grip strength was measured as 35.2 (95% confidence interval [CI]: 34.7-35.8), 36.0 (95% CI: 35.6-36.4), and 36.9 (95% CI: 36.6-37.3) for those who skipped, occasionally ate, and regularly ate breakfast, respectively (p for trend <0.001). Those who always, sometimes, and seldom snacked after dinner (p for trend <0.001) reported the following grip strength: 34.7 (95% CI: 34.0-35.3), 36.2 (95% CI: 35.8-36.6), and 36.9 (95% CI: 36.6-37.2), respectively. Significant associations were not found between eating rate and grip strength., Conclusion: This study showed that higher frequency of breakfast consumption and lower frequency of snacking after dinner were associated with higher grip strength in Chinese adults. Therefore, eating behaviors may be involved in muscle function., Competing Interests: The authors report no conflicts and interest in this work., (© 2020 Ding et al.)

The application of microfluidic technology to manipulate cells or biological particles is becoming one of the rapidly growing areas, and various microarray trapping devices have recently been designed for high throughput single-cell analysis and manipulation. In this paper, we design a double-slit microfluidic chip for hydrodynamic cell trapping at the single-cell level, which maintains a high capture ability. The geometric effects on flow behaviour are investigated in detail for optimizing chip architecture, including the flow velocity, the fluid pressure, and the equivalent stress of cells. Based on the geometrical parameters optimized, the double-slit chip enhances the capture of HeLa cells and the drug experiment verifies the feasibility of the drug delivery., Competing Interests: The authors declare no conflict of interest.

Objective: Although several studies report a relationship between breakfast consumption and physical fitness, results are inconsistent and lack evidence in young adults. The objective of this study was to investigate the relationship between frequency of breakfast consumption and physical fitness among college students., Methods: This cross-sectional study investigated 10,125 Chinese college students (6251 male, 3874 female participants) who underwent physical examinations in 2015. Breakfast consumption was assessed using a self-reported questionnaire. Physical fitness was evaluated by grip strength and 50-meter sprint., Results: After adjusting for confounding factors, a significantly positive association was observed between frequency of breakfast consumption and grip strength (p < .001 for both sexes). Frequent breakfast consumption also was associated with faster sprint times in male and female participants (p < .001, and .002 respectively)., Conclusions: We found that frequent breakfast consumption is significantly associated with higher grip strength and faster sprint times in Chinese college students.

Objective: To study the effects of educational background of men who have sex with men (MSM) on their high risk sexual behaviors and the HIV/STI infection rates., Methods: During July to November of 2009 and March to October of 2010, snowball and convenience sampling methods were adopted to recruit MSM from MSM venues and via the internet in Changzhou city of Jiangsu province, and finally 659 MSM were conducted a questionnaire survey and serological testing. According to the educational background of MSM, they were divided into 3 groups, that is, junior high school group (206 cases), high school group (254 cases), and university group (199 cases). The questionnaire mainly includes information on social demography, sexual behaviors, condom use, etc. Blood samples were collected for HIV and syphilis spirochete detection, and urine samples were also collected in 291 MSM who were recruited during July to November of 2009 for neisseria gonorrhoeae and chlamydia trachomatis nucleic acid detection. χ(2) test and other statistical analysis methods were used to compare the characteristics of sexual behaviors and HIV/STI infections in 3 groups., Results: Of the 659 valid questionnaires returned, junior high school group, high school group, and university group accounted for 31.3% (206 cases), 38.5% (254 cases) and 30.2% (199 cases). Places where MSM of different education levels most often to seek sexual partners, were significantly different. Junior high school group and high school group mostly went to bath house/sauna club (56.3%, 116 cases) and bar (34.8%, 88 cases) for partners, respectively, while the university group sought partners mainly through the internet (41.1%, 81 cases) (χ(2) = 99.35, P < 0.05). 53.4% (109/204) of the junior high school group had anal sex with men in the last 6 months, which was higher than that of high school group (67.7%, 172/254) (χ(2) = 9.74, P < 0.05) and university group (72.7%, 144/198) (χ(2) = 16.04, P < 0.05) . A total of 54.4% (111/204) of the junior high school group had sex with women in the last 6 months, which was higher than that of university group (38.6%, 76/197) (χ(2) = 10.10, P < 0.05) , but was not statistically significantly different from that of high school group (46.9%, 119/254) (χ(2) = 2.59, P = 0.11) . The rates of condom use with men at the last anal sex in junior high school group (73.4%, 80/109) , high school group (78.0%, 131/168) and university group (73.9%, 105/142) were similar. The rates of condom use with women in the last intercourse in junior high school group, high school group and university group were 51.8% (57/110), 54.6% (65/119) and 61.8% (47/76), respectively(χ(2) = 1.88, P = 0.39) . In junior high school group, high school group and university group, the infection rates of HIV were 9.2% (19/206), 10.6% (27/254) and 5.6% (11/197) (χ(2) = 3.68, P = 0.16), the positive rates of neisseria gonorrhoeae were 3.8% (3/79), 3.4% (4/117) and 0.0% (0/95) (χ(2) = 3.85, P = 0.14), the positive rates of chlamydia trachomatis were 5.1% (4/79), 9.4% (11/117) and 4.2% (4/95) (χ(2) = 2.70, P = 0.26). The infection rate of syphilis in junior high school group was 19.9% (41/206), which was higher than high school group (12.2%, 31/254) (χ(2) = 5.11, P < 0.05) and university group (10.2%, 20/197) (χ(2) = 7.45, P < 0.05 )., Conclusion: There was no obvious correlation between education level and high risk sexual behaviors;MSM with lower education level were at higher risk of infection of syphilis.