A varus dropped foot, one of the most common deformities of hemiplegic lower limb in stroke patients, significantly affected the ability of ambulation. Electric stimulation therapy was one of mostly used techniques for this problem. This paper focused on the application of low frequency electric stimulation in the treatment of the varus dropped foot in stroke patients, analyzed the clinical efficacy and advantage of neuromuscular electrical stimulation and functional electrical stimulation, and the discussion of their mechanism.

Microcell mediated chromosome transfer (MMCT) is a challenging technique for introducing exogenous chromosomes into interested mammalian cells. Combined with the somatic cell nuclear transfer technique, MMCT has been employed for producing transchromosomic animals of medical and agricultural value. Producing high quality of microcells is a key step in the success of MMCT. Eamamined by fluorescin staining and Giemsa staining, 0.2 mg/L colcemid was considered suitable for inducing high percentage of micronuclei in A9 (neo12) cells, without causing death of a mass of cells. Microcells were produced by centrifugation of micronucleated A9 (neo12) cells in Percoll density gradient containing 20 mg/L Cytochalasin B at 39 000 g. The resulting mixture of microcells, whole cells, karyoplasts and cytoplast fragments was filtered through 8 μm and 5 μm size membrane pores sequentially to obtain pure preparation of microcells. Microcells were then characterized by Giemsa staining and microcell PCR was first applied for examination of the quality of microcell preparation. The result showed that microcells containing our interest chromosomes-human chromosome 12 were equally distributed in the preparation, the preparation was suitable for use in generation of transchromosomic animals.

[Objective] To explore the variety of matrix metalloproteinase 9 (MMP9) and blood brain barrier (BBB) in cardiopulmonary resuscitation rats.[Methods] Eighty rats were randomly divided into 2 groups:the sham-operated group (n ＝ 40) and the resuscitation group (n ＝ 40).The two groups were anaesthetized and endotracheally intubated,the resuscitation group was also induced to cardiac arrest by aphysia.Then the rats were put to death and samples were taken at immediate,3 h,9 h,24 h,and 48 h.After that,the expression of MMP9,MMP9 mRNA,water content and Evans blue content in brain tissue were detected.Ultramicrostructure of brain tissue was observed with electron microscope.[Results] Compared to the sham-operated group,at 3 h,9 h,24 h and 48 h,the expression of MMP9 of resuscitation group was significantly changed.MMP9mRNA significantly increased.Water content statistically increased and so was Evans blue content.The change of ultramicrostructure in the resuscitation group at 3 h,9 h,24 h,and 48 h was obvious.[Conclusion] The expression of MMP9 and MMP9mRNA obviously increased in the cerebral ischemia model with CPR rats,and got to peak at 24 h.Water content and Evans blue content in brain tissue obviously increased in the cerebral ischemia model with CPR rats,BBB was destroyed,and the peak was 24 h.The injury of ultramicrostructure of brain tissue with electron microscope was obvious,and the peak was 24 h.

BACKGROUND: Vascular intimal hyperplasia (IH) is one of the key challenges in the clinical application of smalldiameter vascular grafts. Current tissue engineering strategies focus on vascularization and antithrombotics, yet few approaches have been developed to treat IH. Here, we designed a tissue-engineered vascular scaffold with portulaca flavonoid (PTF) composition and biomimetic architecture.METHOD: By electrospinning, PTF is integrated with biodegradable poly(e-caprolactone) (PCL) into a bionic vascular scaffold. The structure and functions of the scaffolds were evaluated based on material characterization and cellular biocompatibility. Human vascular smooth muscle cells (HVSMCs) were cultured on scaffolds for up to 14 days. RESULTS: The incorporation of PTF and preparation parameters during fabrication influences the morphology of the scaffold, including fibre diameter, structure, and orientation. Compared to the PCL scaffold, the scaffolds integrated with bioactive PTF show better hydrophilicity and degradability. HVSMCs seeded on the scaffold alongside the fibres exhibit fusiform-like shapes, indicating that the scaffold can provide contact guidance for cell morphology alterations. This study demonstrates that the PCL/PTF (9.1%) scaffold inhibits the excessive proliferation of HVSMCs without causing cytotoxicity. CONCLUSION The study provides insights into the problem of restenosis caused by IH. This engineered vascular scaffold with complex function and preparation is expected to be applied as a substitute for small-diameter vascular grafts.

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.