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.

The general models for intermediates quality analysis in the production process of Yaobitong capsule were established by near infrared spectroscopy (NIRS) combined with chemometrics, realizing the rapid determination of notoginsenoside R1, ginsenoside Rg1, ginsenoside Re, ginsenoside Rb1, ginsenoside Rd and moisture. The spray-dried fine powder and total mixed granule were selected as research objects. The contents of five saponins were determined by high performance liquid chromatography and the moisture content was determined by drying method. The measured contents were used as reference values. Meanwhile, NIR spectra were collected. After removing abnormal samples by Monte Carlo cross validation (MCCV), Monte Carlo uninformative variables elimination (MC-UVE) and competitive adaptive reweighted sampling (CARS) were used to select feature variables respectively. Based on the feature variables, quantitative models were established by partial least squares regression (PLSR), extreme learning machine (ELM) and ant lion optimization least squares support vector machine (ALO-LSSVM). The results showed that CARS-ALO-LSSVM model had the optimum effect. The correlation coefficients of the six index components were greater than 0.93, and the relative standard errors were controlled within 6%. ALO-LSSVM was more suitable for a large number of samples with rich information, and the prediction effect and stability of the model were significantly improved. The general models with good predicting effect can be used for the rapid quality determination of Yaobitong capsule intermediates.

Objective To analyze the structural and phylogenetic characteristics of the mitochondrial genome from Bulinus globosus, so as to provide a theoretical basis for classification and identification of species within the Bulinus genus, and to provide insights into understanding of Bulinus-schistosomes interactions and the mechanisms of parasite transmission. Methods B. globosus samples were collected from the Ruya River basin in Zimbabwe. Mitochondrial DNA was extracted from B. globosus samples and the corresponding libraries were constructed for high-throughput sequencing on the Illumina NovaSeq 6000 platform. After raw sequencing data were subjected to quality control using the fastp software, genome assembly was performed using the A5-miseq and SPAdes tools, and genome annotation was conducted using the MITOS online server. Circular maps and sequence plots of the mitochondrial genome were generated using the CGView and OGDRAW software, and the protein conservation motifs and structures were analyzed using the TBtools software. Base composition and codon usage bias were analyzed and visualized using the software MEGA X and the ggplot2 package in the R software. In addition, a phylogenetic tree was created in the software MEGA X after sequence alignment with the software MAFFT 7, and visualized using the software iTOL. Results The mitochondrial genome of B. globosus was a 13 730 bp double-stranded circular molecule, containing 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and 13 protein-coding genes, with a marked AT preference. The mitochondrial genome composition of B. globosus was similar to that of other species within the Bulinus genus. Phylogenetic analysis revealed that the complete mitochondrial genome sequence of B. globosus was clustered with B. truncatus, B. nasutus, and B. ugandae into the same evolutionary clade, and gene superfamily analysis showed that the metabolism-related proteins of B. globosus were highly conserved, notably the cytochrome c oxidase family, which showed a significant consistency. Conclusions This is the first whole mitochondrial genome sequencing to decode the compositional features of the mitochondrial genome of B. globosus from Zimbabwe and its evolutionary relationship within the Bulinus genus, which provides important insights for further understanding of the phylogeny and mitochondrial genome characteristics of the Bulinus genus.

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:Black phosphorus has a high degree of homology with human bone,so it has been extensively studied in the field of bone tissue engineering in recent years.Since 2014,two-dimensional black phosphorus materials have garned significant attention in the field of biomedicine due to their excellent exceptional physical,chemical,and biological properties. OBJECTIVE:To summarize the advancements made in black phosphorus-based nanomaterials for bone tissue engineering,focus on the synthesis methods,osteogenic characteristics,and applications in biomaterials pertaining to two-dimensional black phosphorus nanomaterials. METHODS:Chinese and English key words were"black phosphorus,bone tissue engineering,bone defect,bone regeneration,osteogenesis."Relevant articles in PubMed and CNKI databases from January 2014 to December 2023 were searched.After exclusion and screening,96 articles were analyzed. RESULTS AND CONCLUSION:Black phosphorus nanomaterials play an important role in bone tissue engineering due to their good biocompatibility,biodegradability,photothermal action,antibacterial ability,drug loading performance,and special osteogenic effect,and are ideal candidate materials for promoting bone regeneration.The preparation of black phosphorus nanomaterials is mainly a top-down top-layer stripping method.The main principle is to weaken the van der Waals force between the black phosphorus layers by physical or chemical means to obtain a single or less layer of phosphanse,that is,black phosphorus nanosheets or quantum dots.Black phosphate-based nanocomposites are mainly divided into hydrogels,3D printing scaffolds,composite scaffolds,electrospinning,bionic periosteum,microspheres,and bionic coatings.The research of nano-black phosphorus in bone tissue engineering is in its infancy,and still faces many challenges:the behavior of black phosphorus in vivo and the interaction mechanism with various biomolecules need to be further studied.The long-term potential toxicity of black phosphorus is unknown.The manufacturing process for black phosphorus is difficult to control.Therefore,how to develop uniform size,safe,reliable,and efficient nano black phosphorus and transform it into clinical application requires interdisciplinary research on modern biomedical technology,physicochemical technology,and precision manufacturing technology.

BACKGROUND:Erythropoietin has anti-inflammatory,anti-apoptotic,and pro-bone defect repair effects.To date,fewer studies have been conducted on its effects and molecular mechanism underlying restorative dentin formation after pulp injury. OBJECTIVE:To explore the effect of erythropoietin on restorative dentin formation after pulp injury. METHODS:(1)Animal experiment:Thirty-two rats were randomly divided into control group(n=16)and experimental group(n=16).In the experimental group,collagen sponges containing erythropoietin were used to directly cap the pulp at the pulp injury,and in the control group,collagen sponges containing PBS were used to directly cap the pulp at the exposed pulp injury.The cavity was then closed with glass ionomer adhesive.After 2 and 4 weeks of treatment,the maxillary bones of the two groups were collected,and the expression of nestin in dentin was detected by immunohistochemistry,and the reparative dentin production was observed by hematoxylin-eosin staining.The maxillae of four Sprague-Dawley rats were taken for immunohistochemical detection of erythropoietin expression in molar and incisor teeth.(2)Cell experiment:Human dental pulp cells,human periodontal ligament cells and human gingival fibroblasts were obtained from human dental tissue,periodontal ligament,and gingival tissue.Real-time reverse transcription PCR(RT-PCR)was used to detect the mRNA expression of erythropoietin.Erythropoietin,dentin sialophosphoprotein,dentin matrix protein 1,and nestin mRNA levels in human pulp cells were detected by RT-PCR under induced or uninduced odontoblastic differentiation.After down-regulation of erythropoietin expression or exogenous administration of erythropoietin intervention under induced or uninduced differentiation odontoblastic differentiation,the relative mRNA expression of dentin sialophosphoprotein and dentin matrix protein 1 in human pulp cells was detected by RT-PCR,and the formation of mineralized nodules was detected by alizarin red S staining,and mRNA and protein expressions of bone morphogenetic protein 2 were detected by RT-PCR and western blot,respectively. RESULTS AND CONCLUSION:(1)Animal experiment:Compared with the control group,the restorative dentin production and nestin expression were higher in the experimental group after 2 and 4 weeks of treatment.The expression of erythropoietin was weakly positive in pulp,odontoblastic cell layer and periodontal membrane of the rat's first maxillary molar,and strongly positive in odontoblasts.(2)Cell experiment:The mRNA expression of erythropoietin was higher in human dental pulp cells than in the other two types of cells.The mRNA expressions of dentin sialophosphorin,dentin matrix protein 1,nestin,erythropoietin and bone morphogenetic protein 2 in human pulp cells increased and the formation of mineralized nodules during odontoblastic differentiation under induction compared with non-induction conditions.The mRNA expression of dentin sialophosphoprotein,dentin matrix protein 1,nestin,bone morphogenetic protein 2 and the formation of mineralized nodules were decreased in human pulp cells after downregulation of erythropoietin under induced odontoblastic differentiation,and the protein expression of bone morphogenetic protein 2 was also decreased.After exogenous erythropoietin intervention,the expression of the above indexes in human dental pulp cells increased.To conclude,erythropoietin can promote the formation of dentin to some extent.