Clinical characteristics of severe pre-eclampsia in a single tertiary referral center of Xiamen City / 中华妇产科杂志

Objective: To explore the key points for preventing and reducing severe pre-eclampsia (SPE) and its severe complications in the tertiary medical referral system of a second-tier city by analyzing the clinical characteristics of SPE. Methods: The clinical data of 341 patients with SPE who terminated pregnancy in Women and Children's Hospital, School of Medicine, Xiamen University, from January 1, 2020 to December 31, 2022 were retrospectively analyzed, and the pre-eclampsia (PE) risk factors, clinical characteristics and severe complications of SPE between the patients referred from primary hospitals (referral group) and the patients received regular prenatal care in the tertiary referral center (central group) were compared, as well as the influence of the referral timing on the maternal and perinatal outcomes. Results: Among the 341 cases of SPE, 92 cases were in the referral group and 249 cases were in the central group. (1) Analysis of PE risk factors: there was no statistical difference in the proportion of risk factors of PE between these two groups [75.0% (69/92) vs 71.9% (179/249); χ2=0.328, P=0.567]. (2) Analysis of clinical features: the gestational ages at the PE early warning factors onset, at the PE first symptom onset and at SPE diagnosed, pregnancy terminated and onset of SPE severe complications in the referral group were significantly earlier than those in the central group (all P<0.05), the proportions of terminating pregnancy before 32 weeks of gestation, between 32 and 34 weeks of gestation, intensive care unit (ICU), neonatal ICU hospitalization and fetal growth restriction in single pregnancies were higher than those in the central group, while the live birth rate was lower than that in the central group (all P<0.05). (3) Analysis of SPE severe complications: the rates of SPE severe complications in the referral group was higher than that in the central group [28.3% (26/92) vs 13.7% (34/249); χ2=9.885, P=0.002]. Among them, the rates of placental abruption [7.6% (7/92) vs 2.8% (7/249); χ2=3.927, P=0.048] and still birth [6.5% (6/92) vs 0.4% (1/249); χ2=9.656, P=0.002] in the referral group were significantly higher than those in the central group. (4) Analysis of referral timings: the timings included referral after onset of SPE severe complications (9.8%, 9/92), referral after SPE diagnosed (63.0%, 58/92), referral after detection of SPE early warning signs (20.7%, 19/92) and referral after detection of PE risk factors (6.5%, 6/92). The gestational ages at SPE diagnosed and pregnancy terminated in group of referral after onset of SPE severe complications and group of referral after SPE diagnosed were significantly earlier than those in group of referral after detection of PE early warning signs and group of referral after detection of PE risk factors (P<0.05). The earlier the referral, the higher the live birth rates (P<0.05). Conclusions: The tertiary referral center of the second-tier city plays an important role in reducing the maternal and perinatal damage of PE. The timing of referral in primary medical institutions is the key point of reducing the occurrence of SPE severe complications and maternal, perinatal damage of PE. It is necessary for medical institutions of all levels in all regions to improve the ability of early identification and early intervention for PE, to enhance the awareness of SPE and its severe complications prevention and control. Primary medical institutions should especially pay attention to raise the consciousness of PE risk factors and early warning signs, and to improve the ability of PE risk factors and early warning signs screening.

Precise assembly of inside-out cell membrane camouflaged nanoparticles via bioorthogonal reactions for improving drug leads capturing

Cell membrane camouflaged nanoparticles have been widely used in the field of drug leads discovery attribute to their unique biointerface targeting function. However, random orientation of cell membrane coating does not guarantee effective and appropriate binding of drugs to specific sites, especially when applied to intracellular regions of transmembrane proteins. Bioorthogonal reactions have been rapidly developed as a specific and reliable method for cell membrane functionalization without disturbing living biosystem. Herein, inside-out cell membrane camouflaged magnetic nanoparticles (IOCMMNPs) were accurately constructed via bioorthogonal reactions to screen small molecule inhibitors targeting intracellular tyrosine kinase domain of vascular endothelial growth factor recptor-2. Azide functionalized cell membrane acted as a platform for specific covalently coupling with alkynyl functionalized magnetic Fe3O4 nanoparticles to prepare IOCMMNPs. The inside-out orientation of cell membrane was successfully verified by immunogold staining and sialic acid quantification assay. Ultimately, two compounds, senkyunolide A and ligustilidel, were successfully captured, and their potential antiproliferative activities were further testified by pharmacological experiments. It is anticipated that the proposed inside-out cell membrane coating strategy endows tremendous versatility for engineering cell membrane camouflaged nanoparticles and promotes the development of drug leads discovery platforms.

Subchronic Oral Toxicity Evaluation of Sodium Dehydroacetate: A 90-day Repeated Dose Study in Rats / 生物医学与环境科学（英文）

Objective@#The present study was undertaken to evaluate the subchronic oral toxicity of sodium dehydroacetate (DHA-Na) and to determine the point of departure (POD), which is a critical factor in the establishment of an acceptable dietary intake.@*Methods@#DHA-Na was administered once daily by gavage to Sprague-Dawley rats at dose levels of 0.0, 31.0, 62.0, and 124.0 mg/kg BW per day for 90 days, followed by a recovery period of 4 weeks in the control and 124.0 mg/kg BW per day groups. The outcome parameters were mortality, clinical observations, body weights, food consumption, hematology and clinical biochemistry, endocrine hormone levels, and ophthalmic, urinary, and histopathologic indicators. The benchmark dose (BMD) approach was applied to estimate the POD.@*Results@#Significant decreases were found in the 62.0 and 124.0 mg/kg BW groups in terms of the body weight and food utilization rate, whereas a significant increase was found in the thyroid stimulating hormone levels of the 124.0 mg/kg BW group. Importantly, the 95% lower confidence limit on the BMD of 51.7 mg/kg BW was modeled for a reduction in body weight.@*Conclusion@#The repeated-dose study indicated the slight systemic toxicity of DHA-Na at certain levels (62.0 and 124.0 mg/kg BW) after a 90-day oral exposure.

Effect of High Suspension and Low Incision Surgery Based on Traditional Ligation of Chinese Medicine in Treatment of Mixed Haemorrhoids: A Multi-centre, Randomized, Single-Blind, Non-inferiority Clinical Trial / 中国结合医学杂志

OBJECTIVE@#To observe the clinical effect of high suspension and low incision (HSLI) surgery on mixed haemorrhoids, compared with Milligan-Morgan haemorrhoidectomy.@*METHODS@#A multi-centre, randomized, single-blind, non-inferiority clinical trial was performed. Participants with mixed haemorrhoids from Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing Rectum Hospital, Air Force Medical Center of People's Liberation Army of China, and Puyang Hospital of Traditional Chinese Medicine were enrolled from September 2016 to March 2018. By using a blocked randomization scheme, participants were assigned to two groups. The experimental group was treated with HSLI, while the control group was treated with Milligan-Morgan haemorrhoidectomy. The primary outcome was the clinical effect evaluated at 12 weeks after operation. The secondary outcomes included the number of haemorrhoids treated during the operation, pain scores, use of analgesics, postoperative oedema, wound healing, incidence of anal stenosis, anorectal manometry after operation, as well as surgical duration, length of stay and total hospitalization expenses. A safety evaluation was also conducted.@*RESULTS@#In total, 246 eligible participants were enrolled, with 123 cases in each group. There was no significant difference in the clinical effect between the two groups (100.00% vs. 99.19%, P>0.05). Compared with the control group, the number of external haemorrhoids treated during the operation and the pain scores after operation were significantly reduced in the experimental group (P0.05). The surgical duration and length of stay in the experimental group were significantly longer than those in the control group, and the total hospitalization expense was significantly higher than that in the control group (all P<0.05). No adverse events were reported in either group during the whole trial or follow-up period.@*CONCLUSION@#HSLI had the advantages of preserving the skin of anal canal completely, alleviating postsurgical pain and promoting rapid recovery after operation. (Registration No. ChiCTR1900022883).

Progress in diagnosis and treatment of fracture-related infection / 国际外科学杂志

Fracture-related infection is one of the most feared complications for orthopedic surgeons and patients. What is more frightening than aseptic bone nonunion is the presence of deep or shallow bone tissue infection at the broken end of the fracture.The high rate of recurrence of bone infections, long treatment cycles and the risk of disability, amputation and death bring physical and mental suffering to patients.At the same time, the complexity of the disease puts forward higher requirements for the diagnosis and treatment of orthopedic doctors. This paper reviews the treatment methods of fracture related infections in recent years at home and abroad.

Bioprinted HepG2 cells for studying sonodynamic anticancer activity of chlorine e6 / 药学学报

This paper showed bioprinted HepG2 tumor tissues used for studying the sonodynamic anticancer activity of chlorine e6 (Ce6). HepG2 cells were printed by using alginate/gelatin/hydroxyethyl cellulose composite biomaterial as bio ink and cell viability was detected with Live-Dead assay and MTT proliferation. The ultrasonic intensities of self-built micro ultrasonic device under different powers were estimated by using the temperature change caused by the conversion of acoustic energy to heat energy. Ce6 of 14.3 and 28.6 μg·mL-1 were acted on two-dimensional cultured and three-dimensional printed HepG2 cells, and the antitumor activity of Ce6 was detected by MTT method with ultrasound intensity of 0.15 W·cm2 for 60 s. The results showed that the activities of bioprinted HepG2 cells were as high as 95%, and tumor microspheres were formed after 7 days of culture. The ultrasound intensity was lower than 3 W·cm2, which belonged to low ultrasound intensity and had no damage to normal hepatocyte LO2 cells. By comparing the antitumor activity of Ce6 on 2D cultured and printed HepG2 cells, it was found that the anticancer activity of Ce6 on bioprinted HepG2 cells was 63.4% lower than that on 2D culture cells, indicating the acoustic drug resistance of three-dimensional tumor model. Bioprinted tumor tissues show the potential in the application of in vitro activity evaluation models for sonodynamic therapy.

Effect of abnormal oligonucleotide binding folding domain protein gene on the initiation of DNA replication in hepatocellular carcinoma / 医学研究生学报

ObjectiveThere are few reports about abnormal oligonucleotide binding fold domain protein genes (OBGs) affecting the initiation of DNA replication in hepatocellular carcinoma through the microchromosome maintenance (MCM) complex. This study aims to explore the roles of reverse-transcription-related genes (RTGs) in Hepatocellular Carcinoma cells (HCC) and the correlation between gene polymorphisms and abnormal gene expression.Methods We created a mouse model by injecting hepatocellular carcinoma cell line H22 (logarithmic growth phase) and dissected the tumor bodies from tumor-forming mice. The control group was treated by isotonic saline without H22. The healthy liver tissue cells were taken from the control mice. The total RNA of the H22 group and control group were extracted, and differentially expressed genes were analyzed. Screening of differentially expressed reverse transcription-related DEGs (RDEGs), GO and KEGG analysis of RDEGs. The interaction analysis of RDEGs encoded proteins, and the correlation analysis of RDEGs polymorphism and gene expression.ResultsThere were 193 differentially expressed RTGs in HCCs, which were involved in two biological procedures, three cell components, one molecular function, three signal pathways, and three functional sites; Its function is mainly concentrated in DNA replication, especially the construction of MCM complex and telomere complex in which OBGs participate in the initiation of replication. Most related genes had OB fold domains. The results also showed that both AS and SNV caused gene polymorphism was positively correlated with gene expression, and most OBGs in HCC had SNV phenomenon, but not occurred in healthy liver tissue.Conclusion Collectively, AS and SNV may be important regulatory factors for gene expression. SNV may particularly affect the function of OBGs in the MCM complex to abnormally initiate DNA replication in HCC.

Intranasal Administration of Melanin-Concentrating Hormone Reduces Stress-Induced Anxiety- and Depressive-Like Behaviors in Rodents

Major depressive disorder is a complex neuropsychiatric disorder with few treatment options. Non-targeted antidepressants have low efficacy and can induce series of side effects. While a neuropeptide, melanin-concentrating hormone (MCH), is known to exhibit regulator of affective state, no study to date has assessed the anti-depressive effects of MCH in a stress-induced depression model. This study aimed to evaluate the pharmacological effects of intranasal administration of MCH on depression-related behavior in stressed rats and mice. Using a number of behavioral tests, we found that MCH treatment significantly decreased anxiety- and depressive-like behaviors induced by stress. Notably, the effects of MCH were equivalent to those of fluoxetine. MCH treatment also restored the activity of the mammalian target of rapamycin (mTOR) signaling pathway and normalized the levels of synaptic proteins, including postsynaptic density 95, glutamate receptor 1, and synapsin 1, which were all downregulated by stress. Interestingly, the protective effects of MCH were blocked by the mTOR inhibitor, rapamycin. These results suggest that MCH exhibits antidepressant properties by modulating the mTOR pathway. Altogether, this study provides an insight into the molecular mechanisms involved in the antidepressant-like effects of MCH, thereby paving the way for the future clinical application of MCH.

Intranasal Administration of Melanin-Concentrating Hormone Reduces Stress-Induced Anxiety- and Depressive-Like Behaviors in Rodents

Major depressive disorder is a complex neuropsychiatric disorder with few treatment options. Non-targeted antidepressants have low efficacy and can induce series of side effects. While a neuropeptide, melanin-concentrating hormone (MCH), is known to exhibit regulator of affective state, no study to date has assessed the anti-depressive effects of MCH in a stress-induced depression model. This study aimed to evaluate the pharmacological effects of intranasal administration of MCH on depression-related behavior in stressed rats and mice. Using a number of behavioral tests, we found that MCH treatment significantly decreased anxiety- and depressive-like behaviors induced by stress. Notably, the effects of MCH were equivalent to those of fluoxetine. MCH treatment also restored the activity of the mammalian target of rapamycin (mTOR) signaling pathway and normalized the levels of synaptic proteins, including postsynaptic density 95, glutamate receptor 1, and synapsin 1, which were all downregulated by stress. Interestingly, the protective effects of MCH were blocked by the mTOR inhibitor, rapamycin. These results suggest that MCH exhibits antidepressant properties by modulating the mTOR pathway. Altogether, this study provides an insight into the molecular mechanisms involved in the antidepressant-like effects of MCH, thereby paving the way for the future clinical application of MCH.

Strategy of schistosomiasis elimination and its effects in Jinhu County, Jiangsu Province / 中国血吸虫病防治杂志

Objective To understand the strategy of schistosomiasis elimination and its effects in Jinhu County, Jiangsu Province. Methods The data of schistosomiasis control in Jinhu County at different stages from 1970 to 2017 were collected and analyzed. Results From 1970 to 2017, there were three stages of schistosomiasis control, including transmission control, transmission interruption, and monitoring and elimination stages in Jinhu County. The main measures included Oncomelania hupensis snail control, infectious source control, and health education. A total of area of 290 691.78 hm2 was detected in Jinhu County, and the area with snails was 3 420.98 hm2. There were 8 729.37 hm2 area with snails was controlled. Since 2014, no O. hupensis snails were found. A total of 525 377 person-times were examined for schistosomiasis, with 2 815 schistosomiasis patients identified, and 2 844 person-times were treated by chemotherapy. In addition, 977 cases received the expand chemotherapy. Since 1990, no local schistosome-infected persons were found. In 2017, the awareness rate of schistosomiasis control knowledge and the correct rate of health behavior were increased by 54.59% and 14.23% respectively compared with those in 1992. Conclusions The comprehensive schistosomiasis control measures implemented in Jinhu County at different periods have achieved remarkable outputs and accelerated the schistosomiasis elimination process. However, the precise control measures should be implemented in the future to consolidate the prevention and control achievements.

Strategy of schistosomiasis elimination and its effects in Jinhu County, Jiangsu Province / 中国血吸虫病防治杂志

Objective To understand the strategy of schistosomiasis elimination and its effects in Jinhu County, Jiangsu Province. Methods The data of schistosomiasis control in Jinhu County at different stages from 1970 to 2017 were collected and analyzed. Results From 1970 to 2017, there were three stages of schistosomiasis control, including transmission control, transmission interruption, and monitoring and elimination stages in Jinhu County. The main measures included Oncomelania hupensis snail control, infectious source control, and health education. A total of area of 290 691.78 hm2 was detected in Jinhu County, and the area with snails was 3 420.98 hm2. There were 8 729.37 hm2 area with snails was controlled. Since 2014, no O. hupensis snails were found. A total of 525 377 person-times were examined for schistosomiasis, with 2 815 schistosomiasis patients identified, and 2 844 person-times were treated by chemotherapy. In addition, 977 cases received the expand chemotherapy. Since 1990, no local schistosome-infected persons were found. In 2017, the awareness rate of schistosomiasis control knowledge and the correct rate of health behavior were increased by 54.59% and 14.23% respectively compared with those in 1992. Conclusions The comprehensive schistosomiasis control measures implemented in Jinhu County at different periods have achieved remarkable outputs and accelerated the schistosomiasis elimination process. However, the precise control measures should be implemented in the future to consolidate the prevention and control achievements.

A Treatment Effect Study of Arthroscope Combined Proximal Humerus Osteotomy in Knee Inversion Osteoarthritis / 昆明医科大学学报

Objective To discover the treatment effect of arthroscope combined with proximal humerus osteotomy in Knee inversion osteoarthritis.Methods From April 2012 to December 2016, 126 cases were diagnosed with knee inversion osteoarthritis in our deparment, then we divided them into two groups randomly, 63 in each group, the control group operated with arthroscope, and the observation group operated with arthroscope combined with proximal humerus osteotomy. The treatment effects of the two groups were compared. Results Two groups of patients'HSS score,VAS score,KSS score before surgery have no statistical significance (P＞0.05) . 6 months post-operation, the HSS score and KSS score have significant increase in both groups, while the VAS score has an obviously reduction. The differences between the two groups have statistical significance (P＜0.05), the treatment effects in two groups have statistical significance (P＜0.05), the observation group has better treatment effect than the control group, and in the case of adverse reactions in both groups, there were no statistical significance (P＞0.05) . Conclusion The treatment of middle-aged and elderly people knee inversion osteoarthritis by arthroscope combined with proximal humerus osteotomy could improve the treatment,soit is worth promoting in clinics.

Comparative analysis on thrombus filtration efficiency for three kinds of convertible vena cava filters / 医用生物力学

Objective To investigate filtration efficiency of convertible vena cava filters on treating pulmonary embolism under the condition of different thrombus diameters and contents.Methods Three kinds of convertible vena cava filter models with different filtering unit structures (L-style,S-style,W-style) were constructed to numerically simulate hemodynamics based on computational fluid dynamic (CFD) methods,and their filtration efficiency was comparatively analyzed under the condition of different thrombus diameters (5,10,15 mm) and contents (10％,15％,20％).Results With the increasing of thrombus diameter and content,the volume fraction of thrombus distributed on the filter bars increased and the filtration efficiency of the filter became better.When the thrombus diameter was 5 mm,the S-style filter's filtration efficiency was the best as compared with the other two kinds of filters.When the thrombus diameter was 10 mm,the W-style filter showed the best filtration efficiency.When the thrombus diameter was 15 mm,the S-style and W-style filter showed the same filtration efficiency,which was better than the L-style filter.Conclusions The implantation of vena cava filters will cause hemodynamic changes,and its filtration efficiency is not only related to filtering unit structures,but also closely related to the diameter and content of thrombus.These results provide a theoretical reference basis for the design and clinical choice of the novel convertible vena cava filter.

Comparative analysis on thrombus filtration efficiency for three kinds of convertible vena cava filters / 医用生物力学

Objective To investigate filtration efficiency of convertible vena cava filters on treating pulmonary embolism under the condition of different thrombus diameters and contents.Methods Three kinds of convertible vena cava filter models with different filtering unit structures (L-style,S-style,W-style) were constructed to numerically simulate hemodynamics based on computational fluid dynamic (CFD) methods,and their filtration efficiency was comparatively analyzed under the condition of different thrombus diameters (5,10,15 mm) and contents (10％,15％,20％).Results With the increasing of thrombus diameter and content,the volume fraction of thrombus distributed on the filter bars increased and the filtration efficiency of the filter became better.When the thrombus diameter was 5 mm,the S-style filter's filtration efficiency was the best as compared with the other two kinds of filters.When the thrombus diameter was 10 mm,the W-style filter showed the best filtration efficiency.When the thrombus diameter was 15 mm,the S-style and W-style filter showed the same filtration efficiency,which was better than the L-style filter.Conclusions The implantation of vena cava filters will cause hemodynamic changes,and its filtration efficiency is not only related to filtering unit structures,but also closely related to the diameter and content of thrombus.These results provide a theoretical reference basis for the design and clinical choice of the novel convertible vena cava filter.

Comparative analysis on thrombus filtration efficiency for three kinds of convertible vena cava filters / 医用生物力学

Objective To investigate filtration efficiency of convertible vena cava filters on treating pulmonary embolism under the condition of different thrombus diameter and content. Methods Three kinds of convertible vena cava filter models with different filtering unit structures (L-style, S-style, W-style) were constructed to numerically simulate hemodynamics based on computational fluid dynamic (CFD) methods, and their filtration efficiency were comparatively analyzed under the condition of different thrombus diameter (5, 10, 15 mm) and content (10%, 15%, 20%). Results With the increasing of thrombus diameter and content, the volume fraction of thrombus distributed on the filter bars increased and filtration efficiency of the filter became better. When the thrombus diameter was 5 mm, the S-style filter’s filtration efficiency was the best as compared with the other two styles of filters. When the thrombus diameter was 10 mm, the W-style filter showed the best filtration efficiency. When the thrombus diameter was 15 mm, the S-style and W-style filter showed the same filtration efficiency, which was better than the L-style filter. Conclusions The implantation of vena cava filters will cause hemodynamic changes, and its filtration efficiency is not only related to filtering unit structures, but also closely related to the diameter and content of thrombus. These results provide a theoretical reference basis for the design and clinical choice of the novel convertible vena cava filter.

PM2.5 induces oxidative stress and histopathological changes in the uterus of rats / 中国实验动物学报

Objective The aim of this work was to study whether PM2. 5 induces oxidative stress and histopatholog-ical changes in uterine tissue of rats. Methods Thirty 4-week-old female Sprague-Dawley rats were randomly divided into the control group (normal saline), the low dose of PM2.5 group (1. 5 mg/kg) and the high dose of PM2.5 group (37. 5 mg/kg) . After exposed to PM2. 5 for 10 days, the rats were sacrificed to examine the histopathological changes in uterine tissues using H&E staining. The contents of SOD, GSH, MDA and LDH were also determined in the uterine tissues. Results Compared with the control group, PM2. 5 caused changes in the uterine structure, showing a thinner endometrial epithelium and reduction of stromal cells and blood vessels. The assessment of oxidative stress parameters showed that the levels of MDA and LDH in the high dose group were (6. 53 ± 1. 24) nmol/mg prot and (265. 62 ± 24. 65) U/g prot, significantly higher than those in the control group ( P<0. 05 ) . Compared with the control group, the levels of SOD and GSH in the high dose and low dose groups were significantly decreased (P<0. 05). Conclusions PM2.5 exposure can cause damages in the rat uterus by inducing oxidative stress.

Detection of Thrombin Using Double Quenching Molecular Beacon / 分析化学

A double quenching molecular beacon ( MB) with simple structure was designed based on organic quencher and G bases, and a simple detection method for thrombin was developed using this MB. In this MB, FAM and BHQ-1 were selected as fluorophore and organic quencher, three continuous nucleotides with G base were connected with BHQ-1, and the loop of MB was designed as a nucleic acid aptamer of thrombin. In the absence of thrombin, the MB was in the stem-loop structure, the fluorophore FAM was close to BHQ-1 and G bases, the fluorescence of FAM was dual quenched by BHQ-1 and G bases, and the fluorescence signal of FAM was very weak. In the presence of thrombin, MB specifically bound thrombin and formed a G-quadruplex structure. The stem-loop structure of the MB was destroyed, and FAM was separated with BHQ-1 and G bases, leading to recovery of fluorescence of FAM. Under the optimal conditions, the fluorescence intensity of FAM exhibited a good linear relationship with concentration of thrombin in the range of 0. 4-40. 0 nmol/L, and regression equation was △I=24. 63C (nmol/L)+ 13. 06 (R2 =0. 9972) with the detection limit of 0. 18 nmol/L (3σ, n=9). The average recoveries of this method in serum samples were 96. 3%-98. 7%, which indicated that the method had high accuracy.

PM2.5 induces oxidative stress and histopathological changes in the uterus of rats / 中国实验动物学报

Objective The aim of this work was to study whether PM2. 5 induces oxidative stress and histopatholog-ical changes in uterine tissue of rats. Methods Thirty 4-week-old female Sprague-Dawley rats were randomly divided into the control group (normal saline), the low dose of PM2.5 group (1. 5 mg/kg) and the high dose of PM2.5 group (37. 5 mg/kg) . After exposed to PM2. 5 for 10 days, the rats were sacrificed to examine the histopathological changes in uterine tissues using H&E staining. The contents of SOD, GSH, MDA and LDH were also determined in the uterine tissues. Results Compared with the control group, PM2. 5 caused changes in the uterine structure, showing a thinner endometrial epithelium and reduction of stromal cells and blood vessels. The assessment of oxidative stress parameters showed that the levels of MDA and LDH in the high dose group were (6. 53 ± 1. 24) nmol/mg prot and (265. 62 ± 24. 65) U/g prot, significantly higher than those in the control group ( P<0. 05 ) . Compared with the control group, the levels of SOD and GSH in the high dose and low dose groups were significantly decreased (P<0. 05). Conclusions PM2.5 exposure can cause damages in the rat uterus by inducing oxidative stress.

Detection of Thrombin Using Double Quenching Molecular Beacon / 分析化学

A double quenching molecular beacon ( MB) with simple structure was designed based on organic quencher and G bases, and a simple detection method for thrombin was developed using this MB. In this MB, FAM and BHQ-1 were selected as fluorophore and organic quencher, three continuous nucleotides with G base were connected with BHQ-1, and the loop of MB was designed as a nucleic acid aptamer of thrombin. In the absence of thrombin, the MB was in the stem-loop structure, the fluorophore FAM was close to BHQ-1 and G bases, the fluorescence of FAM was dual quenched by BHQ-1 and G bases, and the fluorescence signal of FAM was very weak. In the presence of thrombin, MB specifically bound thrombin and formed a G-quadruplex structure. The stem-loop structure of the MB was destroyed, and FAM was separated with BHQ-1 and G bases, leading to recovery of fluorescence of FAM. Under the optimal conditions, the fluorescence intensity of FAM exhibited a good linear relationship with concentration of thrombin in the range of 0. 4-40. 0 nmol/L, and regression equation was △I=24. 63C (nmol/L)+ 13. 06 (R2 =0. 9972) with the detection limit of 0. 18 nmol/L (3σ, n=9). The average recoveries of this method in serum samples were 96. 3%-98. 7%, which indicated that the method had high accuracy.

Simulation on flexibility of the vascular stent and grey correlation analysis / 医用生物力学

Objective To analyze and compare the effects of structure parameters on synchronous motor ability between the blood vessel and stent after stent implantation by using finite element method and grey correlation theory. Methods The magnesium alloy stent of S closed-loop type was selected, and 9 models of such stents with different materials, numbers of support in circumferential direction, support lengths and initial diameters were established by using SolidWorks, and these stent models were meshed by using HyperMesh. The synchronous motor ability between the blood vessel and stent after stent implantation was simulated by using ABAQUS, and the influencing factors of different structure parameters on bending stiffness were investigated and compared by using grey correlation theory. Results The effect of materials on stent flexibility was obvious. The flexibility of magnesium alloy stent was the best, and the bending stiffness was 0.958 N•(rad•mm)-1; the best flexibility of stents were those with 5-support in circumferential direction, 1.0 mm-support length, and 1.4 mm-initial diameter, and their bending stiffness was 0.853,0.829 and 1.024 N•(rad•mm)-1, respectively. Conclusions The flexibility of magnesium alloy stent is the best, followed by stainless steel stent, and cobalt-chromium stent ranks last. With the increase of support numbers in circumferential direction, support length and initial diameter, the stent flexibility shows the decreasing tendency; the grey correlation analysis shows that the effect of materials on stent flexibility is the most significant, followed by support numbers in circumferential direction and support length, while initial diameter exerts the smallest influence. The analysis of structure parameter effects on stent flexibility will provide more scientific guidance for stent design and development as well as its intervention treatment in clinic.