Objective: To compare and analyze the antibacterial effects of platelets against five common clinical pathogenic bacteria including MRSA, SE, SA, E. coli, and CRKP, and to preliminarily explore the role of DCD sensitivity in the observed variations of antibacterial effects. Methods: The same number of platelets were used to establish co-culture systems of platelets and platelet lysates with the five pathogenic bacteria. The antibacterial effects of platelets and platelet lysates on the five pathogenic bacteria were evaluated by observing the turbidity of the bacterial solution, measuring the OD value of the bacterial solution and counting the colonies. The supernatant protein of platelets co-cultured with MRSA was collected for quantitative proteomics analysis to explore the important antibacterial proteins of platelets. The content of DCD in the supernatant after co-culture of platelets and platelet lysates with the five pathogenic bacteria was detected by ELISA to preliminarily analyze the reasons for the different antibacterial effects of platelets on the five pathogenic bacteria. Results: Compared with the control group of MRSA, SA, and SE, the turbidity of the bacterial solution decreased after co-culture of platelets and platelet lysates with MRSA, SA, and SE for 12 h, and the OD value and colony count were significantly reduced (P<0.05). The turbidity of the bacterial solution did not change significantly after co-culture of platelets and platelet lysates with E. coli for 24 h, but the OD value decreased (P<0.05), and the colony count decreased to 10 CFU/mL but the difference was not statistically significant (P>0.05). Compared with the control group of CRKP, the turbidity, OD value, and colony count of the bacterial solution did not change significantly after co-culture of platelets and platelet lysates with CRKP (P>0.05). Proteomics results showed that after co-culture with MRSA, important proteins related to platelet activation, including collagen, fibrinogen, von Willebrand factor, integrin αIIbβ3, platelet glycoprotein V and IV were significantly up-regulated. ELISA results showed that after co-culture with the five pathogenic bacteria, platelets could secrete a large amount of DCD, with the content around 3 μg/mL. Conclusion: The antibacterial effect of platelets on Gram-positive bacteria MRSA, SA, and SE is better than that on Gram-negative bacteria E. coli and CRKP, and platelets have the best antibacterial effect on MRSA. The differences in antibacterial effects of platelets on the five pathogenic bacteria may be related to the sensitivity of DCD antibacterial peptides to the five pathogenic bacteria.

Background::Growth differentiation factor-15 (GDF-15) is a stress response protein and is related to cardiovascular diseases (CVD). This study aimed to investigate the association between GDF-15 and pre-eclampsia (PE).Method::The study involved 299 pregnant women, out of which 236 had normal pregnancies, while 63 participants had PE. Maternal serum levels of GDF-15 were measured by using enzyme-linked immunosorbent assay kits and then translated into multiple of median (MOM) to avoid the influence of gestational week at blood sampling. Logistic models were performed to estimate the association between GDF-15 MOM and PE, presenting as odd ratios (ORs) and 95% confidence intervals (CIs).Results::MOM of GDF-15 in PE participants was higher compared with controls (1.588 vs. 1.000, p < 0.001). In the logistic model, pregnant women with higher MOM of GDF-15 (>1) had a 4.74-fold (95% CI= 2.23-10.08, p < 0.001) increased risk of PE, adjusted by age, preconceptional body mass index, gravidity, and parity. Conclusions::These results demonstrated that higher levels of serum GDF-15 were associated with PE. GDF-15 may serve as a biomarker for diagnosing PE.

Biological hydroxyapatite(BHA)is widely used in the treatment of clinical bone defects due to its good biocompatibility and osteoconductivity.The clinical application of mateiral size is based on the principle of bone defect area adaptation,which contributes to diversity of BHA sizes.However,different sizes correspond to different hierarchi-cal levels of bone biomimicry.As the size changes,the bone biomimicry hierarchy evolves accordingly and influences the process of bone repair and regeneration through osteo-coagulo-immunomodulation,leading to unstable bone graft outcomes.Therefore,this paper reviews the size effect of clinical BHA,analyzes the multilevel structure of natural bone,proposes the evolution of bone biomimetic hierarchy triggered by the size of BHA,and further analyzes the size-media-ted osteo-coagulo-immunomodulation.Based on the hierarchical levels of bone and its osteo-coagulo-immunomodula-tion effect,we provide a new understanding of the biolog-ical principle of the size effect of biomaterials and a theo-retical basis for the basic research and clinical application of different size BHA materials.

Background::Growth differentiation factor-15 (GDF-15) is a stress response protein and is related to cardiovascular diseases (CVD). This study aimed to investigate the association between GDF-15 and pre-eclampsia (PE).Method::The study involved 299 pregnant women, out of which 236 had normal pregnancies, while 63 participants had PE. Maternal serum levels of GDF-15 were measured by using enzyme-linked immunosorbent assay kits and then translated into multiple of median (MOM) to avoid the influence of gestational week at blood sampling. Logistic models were performed to estimate the association between GDF-15 MOM and PE, presenting as odd ratios (ORs) and 95% confidence intervals (CIs).Results::MOM of GDF-15 in PE participants was higher compared with controls (1.588 vs. 1.000, p < 0.001). In the logistic model, pregnant women with higher MOM of GDF-15 (>1) had a 4.74-fold (95% CI= 2.23-10.08, p < 0.001) increased risk of PE, adjusted by age, preconceptional body mass index, gravidity, and parity. Conclusions::These results demonstrated that higher levels of serum GDF-15 were associated with PE. GDF-15 may serve as a biomarker for diagnosing PE.

Objective To explore the association between iron metabolism indexes and the risk of gestational diabetes mellitus(GDM)in pregnant women with advanced age.Methods A total of 292 pregnant women,whose age were≥35 years old and gave birth in Taicang First People's Hospital from April 2021 to April 2023,were retrospectively included and divided into GDM group and non-GDM group.The differences of iron metabolism indexes[serum ferritin(SF),serum iron(SI)and hemoglobin(Hb)]measured from the 20 to 24 weeks of gestation were compared between the two groups.Multivariable Logistic regression model was used to explore the association of SF,SI and Hb with GDM.Based on the data of single nucleotide polymorphism from IEU OpenGWAS(http://gwas.mr-cieu.ac.uk/)and FinnGen datasets,two samples Mendelian randomization analysis were conducted to explore the causal relationship between iron metabolism indexes and GDM by using the methods of Inverse Variance Weighted(IVW).Results In the maximally ad-justed multi-factor logistic models,the statistically significant association between SF measured from 20 to 24 weeks of gestation and the risk of GDM was found[odds ratio(95％confident interval)=1.02(1.01-1.04),P=0.001].The association between Hb and GDM was marginally significant[odds ratio(95％confident interval)=1.04(1.00-1.07),P=0.044],but no association between SI and GDM reached statistical significance.However,Mendelian randomization analysis showed there was no significant evidence for causal association between SF,Hb and GDM.Conclusion SF examined at 20 to 24 weeks of gestation could be used as a biomarker of GDM in the pregnant women with advanced age,but no evidence supported the causal association between SF and GDM.

Objective: To investigate the prevalence of hypertension among primary and middle school students living in Suzhou City, Jiangsu Province, so as to provide insights into comprehensive hypertension control among children and adolescents. Methods: Primary and middle school students at ages of 7 to 17 years were recruited for a questionnaire survey in Suzhou City using the stratified cluster random sampling method from September to December, 2020, and the height and body weight were measured. Blood pressure was measured at three separate clinic visits according to the national criteria Reference of Screening for Elevated Blood Pressure among Children and Adolescents Aged 7-18 Years ( WS/T 610-2018 ), and the detection of elevated blood pressure was estimated at three separate visits. In addition, factors affecting elevated blood pressure were identified. Results: A total of 3 713 students were enrolled, including 1 924 boys ( 51.82% ) and 1 789 girls ( 48.18% ). The detection of elevated blood pressure was 13.63%, 5.36%, and 3.37% at three separate visits, respectively, and the prevalence of hypertension ( elevated blood pressure at all three visits ) was 3.37%. The detection rates of elevated blood pressure were all higher at three visits ( 16.90%, 8.40%, and 5.26% ) among students at ages of 12 to 17 years than among students at ages of 7 to 11 years ( 9.65%, 1.67%, and 1.07%, P<0.05 ). The detection of elevated blood pressure was significantly higher in boys ( 15.23% ) than in girls (11.91%) at the first visit ( P<0.05 ), while no significant differences were seen at the second or third visit ( P>0.05 ). In addition, higher detection rates of elevated blood pressure were seen in obese ( 27.62%, 11.51%, and 7.06% ) and overweight students ( 17.45%, 6.95%, and 4.85% ) than in students with normal weight ( 9.44%, 3.54%, and 2.15% ) at all three visits, and greater detection rates of elevated blood pressure were found in obese students than in overweight students at the first and second visits ( P<0.017 ). Conclusions The prevalence of hypertension was 3.37% based on three separate visits among primary and middle school students in Suzhou City. Measurement of blood pressure at three separate visits within different days is effective to reduce the false positive rate of hypertension and decrease misdiagnosis among children and adolescents.

Objective: To explore body mass index (BMI) changes among children and adolescents in Suzhou before and after COVID-19 outbreak, and to provide a reference for improving physical health of children and adolescents. Methods: A total of 569 children and adolescents who had complete BMI information in 2019 were enrolled through stratified cluster sampling from June to July, 2020. Questionnaire survey was conducted, and height and weight were measured to calculate BMI and BMI Z scores. Results: After the epidemic, overweight/obesity rate were 32.0%, compared to 31.6% before the epidemic(χ 2=0.07, P>0.05). Difference of BMI Z scores before (0.37±1.28) and after (0.38±1.27) the epidemic did not show statistically significant (t=-0.28, P>0.05), No significant changes in BMI Z score were found before and affer COVID-19 outbreak similar results were observed (P>0.05), BMI Z scores after the epidemic (0.45±1.32) was higher than it before the epidemic (0.37±1.35) among primary school group (t=2.57, P=0.01), while BMI Z scores after the epidemic (0.27±1.17) was lower than it before the epidemic (0.39±1.18) among middle school group (t=-4.29, P<0.01). Proportion of sweet food consumption and outdoor activities was statistically different before and after the epidemic(P>0.05), proportion of sugar-sweetened beverages consumption and fried food intake were statistically different before and after the epidemic (P<0.05), sleep time after the epidemic (8.52±1.83)h was higher than it before the epidemic (8.05±1.70)h (t=4.96, P<0.05). Conclusion Before and after COVID-19 outbreak, BMI and overweight/obesity rates are significantly different among children and adolescents in Suzhou, and there is a slight difference in different studying phases.

Objective:To identify age and gender standardized body mass index among children and adolescents and explore their associations with high blood pressure (HBP) in late adolescence.Methods:The current study was based on the Health Promotion Program for Children and Adolescents, school-based surveillance successively conducted from 2012 to 2019 in Suzhou, China. A total of 11 812 children and adolescents aged 16-18 years, who had ≥4 examination records during 2012-2018 and were also involved in a surveillance program in 2019, were included. Latent class growth mixture modeling was used to identify the BMI-Z trajectories in different genders, and multivariate logistic regression was used to analyze the associations between different BMI-Z trajectories and risk of HBP in late adolescence.Results:Six distinct BMI-Z trajectories were determined for both genders:thin, slightly thin,standard, declining, overweight, and obese. Compared with the regular group, the obesity group had 94.0% ( OR=1.94, 95% CI: 1.43-2.63) and 107.0% ( OR=2.07, 95% CI: 1.33-3.22) increased risk of developing HBP in late adolescence in boys and girls, respectively. However, a neutral association was found between the descending group and HBP in late adolescence. Conclusions:Persistent obesity in children may increase the risk of HBP in their late adolescence. If an obese child restores normal weight before late adolescence, the risk of HBP may reduce.

Background/Aims: Gastroparesis is commonly seen in patients with diabetes and functional dyspepsia with no satisfactory therapies. Dysautonomia is one of the main reasons for the imbalanced motility. We hypothesized that spinal cord stimulation (SCS) is a viable therapy for gastroparesis via the autonomic modulation to improve gastric motility. The aim is to find an optimal method of SCS for treating gastroparesis. Methods: Eight healthy-female dogs were implanted with a gastric cannula, a duodenal cannula, 2 multi-electrode spinal leads, and an implantable pulse generator. Gastric motility index (MI) was used to determine the best stimulation location/parameters of SCS. Optimized SCS was used to improve glucagon-induced gastroparesis. Results: With fixed parameters, SCS at Thoracic 10 (T10) was found most effective for increasing gastric MI (37.8%, P = 0.013). SCS was optimized with different parameters (pulse width: 0.05-0.6 msec, frequency: 5-500 Hz, motor threshold: 30-90%) on T10. Our findings revealed that 0.5 msec, 20 Hz with 90% motor threshold at T10 were the best parameters in increasing MI. Glucagon significantly delayed gastric emptying, and this inhibitory effect was partially blocked by SCS. Gastric emptying at 120 minutes was 25.6% in the control session and 15.7% in glucagon session (P = 0.007 vs control), while it was 22.9% with SCS session (P = 0.041 vs glucagon). SCS with the optimal parameters was found to maximally enhance vagal activity and inhibit sympathetic activity assessed by the spectral analysis of heart rate variability. Conclusions SCS with optimized stimulation location and parameters improves gastric motility in healthy-dogs and accelerates gastric emptying impaired by glucagon via enhancing vagal activity.

Objective: To explore the effect of hyperbaric oxygen preconditioning with different frequency on the survival rate of flap and ischemia-reperfusion injury in rats after transplantation, and to explore the best preconditioning conditions to improve the survival rate of rat flaps after transplantation. Methods: Thirty-six Sprague Dawley rats were randomly divided into four groups according to the random number table method, 9 groups in each group.Four groups of rats were pretreated with hyperbaric oxygen pretreatment for 0, 2, 4, and 6 days before the operation, control group, pretreatment 2 d group, pretreatment 4 d group, and pretreatment 6 d group. Taking the midline of the back of the rat as the axis, an ultra-long random flap with a pedicle at the tail end and about 1 cm from the superior iliac spine was designed and cut to a size of 10.0 cm×2.5 cm. The survival of the flaps in each group was observed and the final survival area and survival rate of the flaps were measured on the 7th day after surgery. On the 7th day after operation, the tissue was taken at a distance of 5 cm from the pedicle, and the histopathology was observed; The content of superoxide dismutase (SOD) and malondialdehyde (MDA) in flap tissue was detected by immunohistochemistry, and the expression rate of positive cells in each group was calculated. Immunofluorescence was used to detect the expression of interleukin-6 (IL-6) in the flap tissue. Results: On the 7th day after the operation, the survival area and survival rate of the transplanted flaps in the hyperbaric oxygen pretreatment group were significantly higher than those in the control group (P<0.05), and the pretreatment 4 d and 6 d groups were significantly higher than the pretreated 2 d group (P<0.05), but there was no significant difference between the pretreated 4 d group and the 6 d group (P=0.095). Pathological observation on the 7th day after operation showed that there was some necrosis in the control group, the vascular cells in the pretreated 2 d group had more vascular structures, and more neovascularization was observed in the pretreated 4 d group. The inflammatory cells were the least in the 6 d pretreatment group, and the neovascularization was the same as the pretreatment 4 d group. The absorbance A value of SOD in the control group was 0.009 7±0.000 3, and the positive expression rate was 20%, which was significantly lower than that in the hyperbaric oxygen pretreatment group. The difference was statistically significant (P<0.05). However, the absorbance A value of MDA in the control group was 0.055 1±0.003 0, and the positive expression rate was 55%, which was significantly higher than that in the hyperbaric oxygen pretreatment group. The difference was statistically significant (P<0.05). Among them, the SOD absorbance A value of the pretreated 2 d group was 0.023 8±0.003 0, and the positive expression rate was 30%, which was lower than the pretreatment 4 d group (absorbance A value 0.046 9±0.003 0, positive expression rate 35%) and 6 d group (absorbance A value 0.047 2±0.003 6, positive expression rate 40%), The MDA absorbance A value of the pretreated 2 d group was 0.037 2±0.003 2, and the positive expression rate was 30%, which was higher than the pretreatment 4 d group (absorbance A value 0.014 7±0.002 4, positive expression rate 5%) and 6 d group (absorbance A value 0.017 0±0.001 8, positive expression rate 10%), the difference was statistically significant (P<0.05). However, there was no significant difference in the expression of SOD and MDA between the pretreated 4 d group and the pretreated 6 d group (P>0.05). The expression of IL-6 in the hyperbaric oxygen pretreatment group was significantly lower than that in the control group (absorbance A value 44.937 0±0.594 0), the difference was statistically significant (P<0.05). The absorbance A value in the pretreated 2 d group was 41.698 0±0.724 0, which was significantly higher than the pretreatment 4 d group (absorbance A value 34.049 0±0.323 0) and 6 d group (absorbance A value 33.524 0±0.639 0). The difference was statistically significant (P<0.05). There was no significant difference in the expression of the pretreated 4 d group compared with the 6 d group (P=0.068). Conclusions Hyperbaric oxygen preconditioning can significantly promote the survival of rat flaps after transplantation. Preoperative hyperbaric oxygen preconditioning once daily for 4 consecutive days, can enhance the tolerance of flap tissue to ischemia and anoxia and reduce tissue ischemia-reperfusion injury.