BACKGROUND: Tissue engineering holds promise for vascular repair and regeneration by mimicking the extracellular matrix of blood vessels. However, achieving a functional and thick vascular wall with aligned fiber architecture by electrospinning remains a significant challenge. METHODS: A novel electrospinning setup was developed that utilizes an auxiliary electrode and a spring. The impact of process parameters on fiber size and morphology was investigated. The structure and functions of the scaffolds were evaluated through material characterization and assessments of cellular biocompatibility. RESULTS: The new setup enabled controlled deposition of fibers in different designed orientations. The fabricated small-diameter vascular scaffolds consisted of an inner layer of longitudinally oriented fibers and an outer layer of circumferentially oriented fibers (L + C vascular scaffold). Key parameters, including rotational speed, the utilization of the auxiliary electrode, and top-to-collector distance (TCD) significantly influenced fiber orientation. Additionally, voltage, TCD, feed rate, needle size, auxiliary electrode and collector-auxiliary electrode distance affected fiber diameter and distribution. Mechanical advantages and improved surface wettability of L + C vascular scaffold were confirmed through tensile testing and water contact angle. Cellular experiments indicated that L + C vascular scaffold facilitated cell adhesion and proliferation, with human umbilical vein endothelial cells and smooth muscle cells attaching and elongating along the fiber direction of the inner and outer layer, respectively. CONCLUSION This study demonstrated the feasibility of fabricating fiber-aligned, thick-walled vascular scaffolds using a modified electrospinning setup. The findings provided insights into how the auxiliary electrode, specific collector influenced fiber deposition, potentially advancing biomimetic vascular scaffold engineering.

BACKGROUND: Tissue engineering holds promise for vascular repair and regeneration by mimicking the extracellular matrix of blood vessels. However, achieving a functional and thick vascular wall with aligned fiber architecture by electrospinning remains a significant challenge. METHODS: A novel electrospinning setup was developed that utilizes an auxiliary electrode and a spring. The impact of process parameters on fiber size and morphology was investigated. The structure and functions of the scaffolds were evaluated through material characterization and assessments of cellular biocompatibility. RESULTS: The new setup enabled controlled deposition of fibers in different designed orientations. The fabricated small-diameter vascular scaffolds consisted of an inner layer of longitudinally oriented fibers and an outer layer of circumferentially oriented fibers (L + C vascular scaffold). Key parameters, including rotational speed, the utilization of the auxiliary electrode, and top-to-collector distance (TCD) significantly influenced fiber orientation. Additionally, voltage, TCD, feed rate, needle size, auxiliary electrode and collector-auxiliary electrode distance affected fiber diameter and distribution. Mechanical advantages and improved surface wettability of L + C vascular scaffold were confirmed through tensile testing and water contact angle. Cellular experiments indicated that L + C vascular scaffold facilitated cell adhesion and proliferation, with human umbilical vein endothelial cells and smooth muscle cells attaching and elongating along the fiber direction of the inner and outer layer, respectively. CONCLUSION This study demonstrated the feasibility of fabricating fiber-aligned, thick-walled vascular scaffolds using a modified electrospinning setup. The findings provided insights into how the auxiliary electrode, specific collector influenced fiber deposition, potentially advancing biomimetic vascular scaffold engineering.

BACKGROUND: Tissue engineering holds promise for vascular repair and regeneration by mimicking the extracellular matrix of blood vessels. However, achieving a functional and thick vascular wall with aligned fiber architecture by electrospinning remains a significant challenge. METHODS: A novel electrospinning setup was developed that utilizes an auxiliary electrode and a spring. The impact of process parameters on fiber size and morphology was investigated. The structure and functions of the scaffolds were evaluated through material characterization and assessments of cellular biocompatibility. RESULTS: The new setup enabled controlled deposition of fibers in different designed orientations. The fabricated small-diameter vascular scaffolds consisted of an inner layer of longitudinally oriented fibers and an outer layer of circumferentially oriented fibers (L + C vascular scaffold). Key parameters, including rotational speed, the utilization of the auxiliary electrode, and top-to-collector distance (TCD) significantly influenced fiber orientation. Additionally, voltage, TCD, feed rate, needle size, auxiliary electrode and collector-auxiliary electrode distance affected fiber diameter and distribution. Mechanical advantages and improved surface wettability of L + C vascular scaffold were confirmed through tensile testing and water contact angle. Cellular experiments indicated that L + C vascular scaffold facilitated cell adhesion and proliferation, with human umbilical vein endothelial cells and smooth muscle cells attaching and elongating along the fiber direction of the inner and outer layer, respectively. CONCLUSION This study demonstrated the feasibility of fabricating fiber-aligned, thick-walled vascular scaffolds using a modified electrospinning setup. The findings provided insights into how the auxiliary electrode, specific collector influenced fiber deposition, potentially advancing biomimetic vascular scaffold engineering.

BACKGROUND: Tissue engineering holds promise for vascular repair and regeneration by mimicking the extracellular matrix of blood vessels. However, achieving a functional and thick vascular wall with aligned fiber architecture by electrospinning remains a significant challenge. METHODS: A novel electrospinning setup was developed that utilizes an auxiliary electrode and a spring. The impact of process parameters on fiber size and morphology was investigated. The structure and functions of the scaffolds were evaluated through material characterization and assessments of cellular biocompatibility. RESULTS: The new setup enabled controlled deposition of fibers in different designed orientations. The fabricated small-diameter vascular scaffolds consisted of an inner layer of longitudinally oriented fibers and an outer layer of circumferentially oriented fibers (L + C vascular scaffold). Key parameters, including rotational speed, the utilization of the auxiliary electrode, and top-to-collector distance (TCD) significantly influenced fiber orientation. Additionally, voltage, TCD, feed rate, needle size, auxiliary electrode and collector-auxiliary electrode distance affected fiber diameter and distribution. Mechanical advantages and improved surface wettability of L + C vascular scaffold were confirmed through tensile testing and water contact angle. Cellular experiments indicated that L + C vascular scaffold facilitated cell adhesion and proliferation, with human umbilical vein endothelial cells and smooth muscle cells attaching and elongating along the fiber direction of the inner and outer layer, respectively. CONCLUSION This study demonstrated the feasibility of fabricating fiber-aligned, thick-walled vascular scaffolds using a modified electrospinning setup. The findings provided insights into how the auxiliary electrode, specific collector influenced fiber deposition, potentially advancing biomimetic vascular scaffold engineering.

BACKGROUND: Tissue engineering holds promise for vascular repair and regeneration by mimicking the extracellular matrix of blood vessels. However, achieving a functional and thick vascular wall with aligned fiber architecture by electrospinning remains a significant challenge. METHODS: A novel electrospinning setup was developed that utilizes an auxiliary electrode and a spring. The impact of process parameters on fiber size and morphology was investigated. The structure and functions of the scaffolds were evaluated through material characterization and assessments of cellular biocompatibility. RESULTS: The new setup enabled controlled deposition of fibers in different designed orientations. The fabricated small-diameter vascular scaffolds consisted of an inner layer of longitudinally oriented fibers and an outer layer of circumferentially oriented fibers (L + C vascular scaffold). Key parameters, including rotational speed, the utilization of the auxiliary electrode, and top-to-collector distance (TCD) significantly influenced fiber orientation. Additionally, voltage, TCD, feed rate, needle size, auxiliary electrode and collector-auxiliary electrode distance affected fiber diameter and distribution. Mechanical advantages and improved surface wettability of L + C vascular scaffold were confirmed through tensile testing and water contact angle. Cellular experiments indicated that L + C vascular scaffold facilitated cell adhesion and proliferation, with human umbilical vein endothelial cells and smooth muscle cells attaching and elongating along the fiber direction of the inner and outer layer, respectively. CONCLUSION This study demonstrated the feasibility of fabricating fiber-aligned, thick-walled vascular scaffolds using a modified electrospinning setup. The findings provided insights into how the auxiliary electrode, specific collector influenced fiber deposition, potentially advancing biomimetic vascular scaffold engineering.

Objective: To investigate the distribution of pupil diameter and its association with myopia in school age children, providing ideas into the mechanisms of the role of pupil diameter in the onset and development of myopia. Methods: Adopting a combination of stratified cluster random sampling and convenience sampling method, 3 839 children from six schools in Shandong Province were included in September 2021. Pupil diameters distribution was analyzed by age, sex, and myopic status. Pearson correlation analysis was used to assess the relationship between pupil diameter and cycloplegic spherical equivalent (SE), as well as axial length (AL) and other variables. Propensity score matching (PSM) was applied to match myopic and non myopic children at a 1∶1 ratio based on age and sex. A generalized linear model (GLM) was constructed with pupil diameter as the dependent variable to identify independent factors influencing pupil size and its association with myopia. Results: The mean pupil diameter of school age children was (5.77±0.80)mm. Pupil diameter exhibited a significant increasing trend with age ( F =49.34， P trend ＜ 0.01). Myopic children had a significantly larger mean pupil diameter [(6.10±0.73)mm] compared to non myopic children [(5.62±0.79)mm] with a statistically significant difference( t=18.10, P <0.01). Multivariable GLM analysis, adjusted for age, amplitude of accommodation, and uncorrected visual acuity, revealed a negative correlation between pupil diameter and cycloplegic SE (before PSM: β =-0.089, after PSM: β =-0.063, both P ＜0.01). Conclusions Myopic school age children exhibite larger pupil diameters than their non myopic counterparts. Pupil diameter may serve as a potential indicator for monitoring myopia development in school age children.

Objective: To analyze the developmental trajectories of middle school students loneliness and social support, as well as to explore the interaction between loneliness and social support, so as to provide the evidence based support for the mental health development of adolescents. Methods: A total of 989 first year students from four public middle schools in Xiangxi Tujia and Miao Autonomous Prefecture, Hunan Province were selected for three follow up surveys by a cluster random sampling method (T1:March 2023, T2:June 2023, T3:December 2023). The UCLA Loneliness Scale-20 (ULS-20) and Social Support Scale for University Students (SSSUS) were employed for questionnaire data collection. The growth mixture modeling was utilized to test the developmental trajectories of loneliness and social support among middle school students, while the cross lagged analysis was performed to investigate their mutual influence. Results: The scores for loneliness and social support in T1, T2 and T3 were (43.1±5.8, 42.5± 6.8 , 42.0±6.9; 55.9±12.0, 60.7±15.7, 60.4±16.7), respectively. Correlational analysis revealed a significant negative correlation between loneliness levels (T1, T2, T3) and social support (T1, T2, T3) ( r =-0.47 to -0.36, P <0.01). Growth mixture modeling indicated a linear declining trend of middle school students loneliness, and the developmental trajectory of social support showed a linear increasing trend, with significant individual differences in initial levels and rates of change ( P <0.05). Cross lagged analyses revealed that loneliness levels at T1 negatively predicted social support scores at T2 ( β =-0.16), and loneliness levels at T2 negatively predicted social support scores at T3 ( β =-0.12) ( P <0.05). Additionally, prior loneliness positively predicted its subsequent levels, with path coefficients of 0.58 and 0.47, respectively ( P <0.05). Social support scores at T1 negatively predicted loneliness levels at T2 ( β =-0.10), while scores at T2 negatively predicted loneliness levels at T3 ( β =-0.15) ( P <0.05). Prior loneliness also positively predicted its subsequent levels, with path coefficients of 0.43 and 0.44, respectively ( P <0.05). Conclusion The developmental trajectory of middle school students loneliness demonstrates a decreasing trend, while that of social support exhibits a linear increasing trend, indicating a longitudinal causal relationship between loneliness and social support.

Objective To analyze the clinical characteristics and typing of cesarean scar endometriosis (CSE).Methods The clinical data of 335 cases of patients with CSE admitted to this hospital from January 2016 to June 2022 were retrospectively analyzed.The correlation between the maximum diameter of the le-sions and other clinical indicators was analyzed,and the clinical characteristics were compared among the pa-tients with different subtypes of lesions.Results The mean age of onset in 335 patients was (30.2±4.2) years,and the incubation period ranged from 1 month to 15 years,with a mean of (35.7±29.3) months.A to-tal of 328 patients received surgical treatment,and 48 patients (14.6％) had two or more previous cesarean sections.The age of onset and maximum diameter of the lesions in patients had two or more previous cesarean sections were higher than those in patients had one previous cesarean section,and the difference was statisti-cally significant (P<0.05).The patients were divided into 26 cases of subcutaneous type,271 cases of sheath type,and 31 cases of peritoneal type according to the depth of lesion invasion.The maximum diameters of the lesions were the peritoneal type>sheath type>subcutaneous type,and the differences were statistically sig-nificant (P<0.05).The serum level of CA125,amount of intraoperative blood loss,and proportions of pa-tients using drainage tubes and patches in the peritoneal type were significantly higher than those in the sub-cutaneous type and sheath type (P<0.05).The maximum diameter of the lesions was positively correlated with gravidity,cesarean section frequency,course of disease,amount of intraoperative blood loss,depth of lesion in-vasion,and proportions of patients using drainage tubes and patches (P<0.05).Conclusion The cesarean section frequency influences the lesion size of patients with CSE to a certain extent.Patients with the peritoneal type have larger lesions,higher amount of intraoperative blood loss,and higher proportions of patches use,which should be of clinical concern.

This paper aims to discuss the ideas and experience about the radiology residency training system of Canada with a presentation of its base accreditation standards for five aspects, competency goals for seven roles, four stages of training arrangement, and two types of final assessment questions. Although the Canada's radiology residency program differs from China's standardized resident and specialist training programs for radiology, there are still several points that are worth referencing, including emphasizing the training priority of competency goals, providing a specific basis for the stratification of training, offering clear guidance for the implementation of training content, and improving assessment methods to focus on competency goals. These points are of great value for improving the standardized radiology resident and specialist training programs in China, so as to provide a reference for the training of excellent radiologists in China.

Objective To investigate the molecular epidemiology of hypervirulent Klebsiella pneumoniae(HvKp)and its independent risk factors for infection,and to provide research basis for anti-infection treat-ment.Methods A total of 519 Klebsiella pneumoniae strains were collected from Inner Mongolia Forestry General Hospital from January 2020 to December 2022.String test was used to distinguish hypermyxoid strains(HMV-Kp)and non-HMV-KP.The rmpA,rmpA2,and iutA genes were detected by common PCR agarose gel electrophoresis to screen the HvKp strains.Multilocus sequence typing analysis was performed on 60 HvKp strains and the minimum spanning tree was drawn.Multivariate Logistic regression was used to ana-lyze the risk factors of HvKp infection.Results The positive rate of HMV-Kp was 39.69％,the positive rate of HvKp was 37.19％,and HMV-Kp accounted for 76.68％of HvKp.The detection rate of HvKp in general surgery department was the highest,and the detection rate of HvKp in pus specimens was the highest.By ST typing comparison,a total of 18 types of 60 HvKp strains were detected,ST23 type was the most common type(50.00％),followed by ST86 type(8.33％).Multivariate Logistic regression analysis showed that male,liver abscess,infection or suppuration of other tissues and organs,and use of macrolide antibiotics in the past 3 months were independent risk factors for HvKp infection(P＜0.05).Conclusion There is a strong associa-tion between HvKp and HMV-Kp strains,and ST23 type is the dominant type in this study.Male,liver ab-scess,infection or suppuration of other tissues and organs,and use of macrolide antibiotics in the past 3 months are independent risk factors for HvKp infection.