The main challenge of ultrasound‐guided minimally invasive surgeries is to carry out treatments through small boreholes in the patient's body surface with sub‐millimetric accuracy and facility ...offered by ultrasound instruments. Thus, the phantoms' biomimetic appearances, acoustic characteristics, and mechanical properties are essential for healthcare professionals. In this study, gelatin and 3D‐printed photo‐resin phantoms were developed for hard and soft tissues, respectively. Using glutaraldehyde (GA) and formaldehyde (FA) to crosslink gelatin phantoms, the mechanical strength, ultrasound velocity, acoustic impedance, needle insertion forces, and antiseptic periods were improved, and the addition of silica nanoparticles raised the acoustic impedance. For 3D‐printed phantoms, the acoustic impedance ascended with hydrophilic polyethylene glycol diacrylate (PEGDA) oligomers. The additives applied in this study successfully made the gelatin and photo‐resin phantoms more mimetic to muscle and bone tissues, allowing their application in preoperative preparations.
3D‐printed photo‐resin phantoms were developed for hard and soft tissues. The additives of crosslinkers, nanoparticles, and reactive monomers improved the mechanical strength, acoustic properties, needle insertion forces, and antiseptic periods of phantoms efficiently.
Early screening may prevent fibrosis progression in metabolic-associated fatty liver disease (MAFLD).
We developed and validated MAFLD fibrosis score (MFS) for identifying advanced fibrosis (≥F3) ...among MAFLD patients.
This cross-sectional, multicentre study consecutively recruited MAFLD patients receiving tertiary care (Malaysia as training cohort n = 276 and Hong Kong and Wenzhou as validation cohort n = 431). Patients completed liver biopsy, vibration-controlled transient elastography (VCTE), and clinical and laboratory assessment within 1 week. We used machine learning to select 'highly important' predictors of advanced fibrosis, followed by backward stepwise regression to construct MFS formula.
MFS was composed of seven variables: age, body mass index, international normalised ratio, aspartate aminotransferase, gamma-glutamyl transpeptidase, platelet count, and history of type 2 diabetes. MFS demonstrated an area under the receiver-operating characteristic curve of 0.848 95% CI 0.800-898 and 0.823 0.760-0.886 in training and validation cohorts, significantly higher than aminotransferase-to-platelet ratio index (0.684 0.603-0.765, 0.663 0.588-0.738), Fibrosis-4 index (0.793 0.735-0.854, 0.737 0.660-0.814), and non-alcoholic fatty liver disease fibrosis score (0.785 0.731-0.844, 0.750 0.674-0.827) (DeLong's test p < 0.05). MFS could include 92.3% of patients using dual cut-offs of 14 and 15, with a correct prediction rate of 90.4%, resulting in a larger number of patients with correct diagnosis compared to other scores. A two-step MFS-VCTE screening algorithm demonstrated positive and negative predictive values and overall diagnostic accuracy of 93.4%, 89.5%, and 93.2%, respectively, with only 4.0% of patients classified into grey zone.
MFS outperforms conventional non-invasive scores in predicting advanced fibrosis, contributing to screening in MAFLD patients.
Objective and Background
To achieve periodontal regeneration, numerous investigations have concentrated on biomolecule supplement and optimization of bone substitute or barrier membrane. This study ...evaluated the benefit of combining these strategies for periodontal regeneration.
Methods
Biphasic cryogel scaffold (BCS) composed of gelatin (ligament phase) and gelatin with beta‐tricalcium phosphate/hydroxyapatite (BH) (bone phase) was designed as tested bone substitute, and both enamel matrix derivatives (EMD) and bone morphogenetic protein‐2 (BMP‐2) were applied to formulate a biomolecule‐aided BCS (BBS). Functionally graded membrane (FGM) was designed as tested barrier membrane by adhering PDGF‐encapsulated poly(L‐lactide‐co‐D/L‐lactide) nanofibers on the conventional membrane (CM). BBS and FGM were characterized and tested for biocompatibility in vitro. Thirty 4 × 4 × 5 mm3 periodontal intrabony defects were created on 6 Beagle dogs. Each defect was evenly assigned to one of the following treatments including BH‐CM, BCS‐CM, BBS‐CM, BH‐FGM, BCS‐FGM, and BBS‐FGM, for 12 weeks. The therapeutic efficiency was assessed by micro‐CT and histology.
Results
BCS and FGM sustained the release of biomolecules. The viability of MSCs was maintained in both phases of BCS and was promoted while seeding on the PDGF‐encapsulated nanofibers. In CM‐covered sites, BBS showed significantly greater osteogenesis (P < .01) and early defect fill (P < .05) relative to BH. FGM significantly promoted osteogenesis (P < .05) in BH‐treated sites but showed limited benefit in BBS‐treated sites. On denuded roots, cementum deposition was evident in BBS‐treated sites.
Conclusions
PDGF‐loaded FGM promoted periodontal osteogenesis, and BBS with EMD‐BMP‐2 had potential for reconstructing alveolar ridge, periodontal ligament, and cementum. FGM and BBS combination provided limited additional benefit.
Background & Aims
aMAP score, as a hepatocellular carcinoma risk score, is proven to be associated with the degree of chronic hepatitis B‐related liver fibrosis. We aimed to evaluate the ability of ...aMAP score for metabolic dysfunction‐associated steatotic liver disease (MASLD; formerly NAFLD)‐related fibrosis diagnosis and establish a machine‐learning (ML) model to improve the diagnostic performance.
Methods
A total of 946 biopsy‐proved MASLD patients from China and the United States were included in the analysis. The aMAP score, demographic/clinical indices and liver stiffness measurement (LSM) were included in seven ML algorithms to build fibrosis diagnostic models in the training set (N = 703). The performance of ML models was evaluated in the external validation set (N = 125).
Results
The AUROCs of aMAP versus fibrosis‐4 index (FIB‐4) and aspartate aminotransferase‐platelet ratio (APRI) in cirrhosis and advanced fibrosis were (0.850 vs. 0.857 P = 0.734, 0.735 P = 0.001) and (0.759 vs. 0.795 P = 0.027, 0.709 P = 0.049). When using dual cut‐off values, aMAP had a smaller uncertainty area and higher accuracy (26.9%, 86.6%) than FIB‐4 (37.3%, 85.0%) and APRI (59.0%, 77.3%) in cirrhosis diagnosis. The seven ML models performed satisfactorily in most cases. In the validation set, the ML model comprising LSM and 5 indices (including age, sex, platelets, albumin and total bilirubin used in aMAP calculator), built by logistic regression algorithm (called LSM‐plus model), exhibited excellent performance. In cirrhosis and advanced fibrosis detection, the LSM‐plus model had higher accuracy (96.8%, 91.2%) than LSM alone (86.4%, 67.2%) and Agile score (76.0%, 83.2%), respectively. Additionally, the LSM‐plus model also displayed high specificity (cirrhosis: 98.3%; advanced fibrosis: 92.6%) with satisfactory AUROC (0.932, 0.875, respectively) and sensitivity (88.9%, 82.4%, respectively).
Conclusions
The aMAP score is capable of diagnosing MASLD‐related fibrosis. The LSM‐plus model could accurately identify MASLD‐related cirrhosis and advanced fibrosis.
Background
Infection control is a major determinant of guided tissue regeneration (GTR). This study aims to develop an antibiotic‐loaded membrane to assist periodontal repair.
Methods
Poly(D,L‐lactic ...acid) (PDLLA) nanofibers encapsulating amoxicillin (PDLLA‐AMX) were fabricated using the electrospinning technique, and their structures, drug encapsulation efficiency, and release characteristics were assessed. The viability and behaviors of periodontal ligament (PDL) cells on nanofibers, and antibacterial capabilities of nanofibers were evaluated in vitro. Early therapeutic efficiency of the antibiotic‐loaded membranes was investigated in rats with ligature‐induced experimental periodontitis, and the outcomes were evaluated by gene expression, microcomputed tomography imaging, and histology within 7 days of membrane placement.
Results
AMX was successfully encapsulated in the PDLLA nanofibers and released in a sustained manner. After initial attachment was achieved, cells stretched out along with the directions of nanofibers. The viability and expression of migration‐associated gene of PDL cells were significantly improved, and the growth of Streptococcus sanguinis and Porphyromonas gingivalis was significantly reduced in the PDLLA‐AMX group compared with the controls. On PDLLA‐AMX‐treated sites, wound dehiscence and sulcular inflammation were reduced. Collagen fiber matrix deposition was accelerated with upregulated type I collagen and interleukin‐1β, and downregulated matrix metalloproteinase‐8, whereas periodontal bone level and the expressions of vascular endothelial growth factor and core‐binding factor subunit alpha‐1 were equivalent to conventional membrane treatment.
Conclusions
PDLLA‐AMX nanofibers inhibited bacterial growth and promoted the viability and mobility of PDL cells after initial cell attachment. Membranes with PDLLA‐AMX nanofibers reduced inflammation and accelerated periodontal repair at an early stage, providing good prospects for the further development of GTR membranes.
Chitosan (CS) electrospun nanofiber (ENF) membranes were modified with fucoidan (Fu) and CuS NPs through polyelectrolyte complexation and genipin (GP)-involved cross-linking reaction. The formation ...of Fu/CS complex and cross-linking of CS with GP increased the acid resistance and reduced the swelling rate of CS ENF, while the covalent conjugation of CuS NPs provided CS ENF with durable Fenton-like catalytic activity. The CuS@ENF composite (ENFC) effectively adsorbed H2O2 and near-infrared (NIR) light, enabling it to kill bacteria by photothermal and photocatalytic bactericidal effects. Fu and copper ions were able to release from the ENFC in a pH-dependent manner, and promoted the alkaline phosphatase activity of osteoblast cells and capillary tube formation of endothelial cells. This study provides a new approach to modify CS ENF with antibacterial and osteoblast differentiation activities, which may be available for bone infection prevention and tissue regeneration.
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•Modifying chitosan electrospun nanofibers (CS ENFs) with fucoidan (Fu) and CuS NPs•Formation of Fu/CS polyelectrolyte complex and covalent conjugation of CuS NPs•CuS@ENF composites have chemo-photodynamic and photothermal bactericidal effects.•CuS@ENF composites promote the alkaline phosphatase activity of osteoblast cells.
A persistent purpose for self-powered and wearable electronic devices is the fabrication of graphene-PVDF piezoelectric nanogenerators with various co-solvents that could provide enhanced levels of ...durability and stability while generating a higher output. This study resulted in a piezoelectric nanogenerator based on a composite film composed of graphene, and poly (vinylidene fluoride) (PVDF) as a flexible polymer matrix that delivers high performance, flexibility, and cost-effectiveness. By adjusting the co-solvent in the solution, a graphene-PVDF piezoelectric nanogenerator can be created (acetone, THF, water, and EtOH). The solution becomes less viscous and is more diluted the more significant the concentration of co-solvents, such as acetone, THF, and EtOH. Additionally, when the density is low, the thickness will be thinner. The final film thickness for all is ~25 µm. Furthermore, the- crystal phase becomes more apparent when graphene is added and combined with the four co-solvents. Based on the XRD results, the peak changes to the right, which can be inferred to be more dominant with the β-phase. THF is the co-solvent with the highest piezoelectric output among other co-solvents. Most of the output voltages produced are 0.071 V and are more significant than the rest.
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•Electrospun CuS nanoparticles/chitosan nanofiber composites (ENFCs) were developed.•The removal mechanism of tetracycline includes adsorption and catalytic degradation.•Visible and ...near-infrared light-driven photo-Fenton degradation of tetracycline.•The degradation intermediates and possible transformation pathways were evaluated.
In the present study, copper sulfide nanoparticles (CuS NPs)/chitosan nanofiber composites with photo-Fenton catalytic and photothermal activities were developed to enhance the removal of recalcitrant biomedical pollutants such as tetracycline (TC). CuS NPs were encapsulated in CS nanofibers by an electrospinning technique (CS ENFs) to obtain CuS@CS ENF composite (CuS@CS ENFC) membranes with high porosity and large surface areas. An investigation of the mechanism of TC removal revealed the complementary performances between adsorption of TC by CS ENFs and the Fenton-like reaction of TC with CuS NPs during the degradation of TC. The ENFCs were cross-linked with genipin (GP) to improve the stability of CuS NPs in long-term storage and the availability of the ENFCs over a wide pH range. CuS@CS ENFCs generated electron-hole pairs and local hyperthermia under near infrared (NIR) laser irradiation, which caused the H2O2-involved catalytic reaction on ENFCs to take place at a faster rate than in the dark. Compared to pristine CuS NPs, ENFCs were more easily separated from the reaction mixture, and the adsorption sites on ENFCs could be regenerated by the photo-Fenton catalytic degradation of TC. The ENFCs also exhibited antibacterial activity. ENFCs are eco-friendly and easily recyclable, so they have the potential for chemical engineering, biomedical, and environmental applications.
Freeze-fixation and freeze-gelation methods are presented in this paper which can be used to prepare highly porous scaffolds without using the time and energy consuming freeze-drying process. The ...porous structure was generated during the freeze of a polymer solution, following which either the solvent was extracted by a non-solvent or the polymer was gelled under the freezing condition; thus, the porous structure would not be destructed during the subsequent drying stage. Compared with the freeze-drying method, the presented methods are time and energy-saving, with less residual solvent, and easier to be scaled up. Besides, the problem of formation of surface skin can be resolved and the limitation of using solvent with low boiling point can be lifted by the presented methods. With the freeze-extraction and freeze-gelation methods, porous PLLA, PLGA, chitosan and alginate scaffolds were successfully fabricated. In addition to the presentation of the morphologies of the fabricated scaffolds, preliminary data of cell culture on them are as well included in the present work.
The present work investigates the effect of cathode electrocatalysts composed of Pt nanowires (Pt-NWs) fabricated by electrospinning method and commercial Pt-loaded carbon black (Pt/C) on the oxygen ...reduction reaction (ORR) in a proton exchange membrane fuel cell. Pt nanowires are prepared by heating electrospun polyvinyl pyrrolidone (PVP)-Pt composite fibers at high temperatures in air atmosphere. Cathode catalyst layers with different mixing ratios of Pt-NWs and Pt/C are tested to explore their activities toward ORR. The results show that the conventional Pt/C mixed with a small amount of Pt-NWs exhibits better catalytic performance than the pure Pt/C catalysts. Under the same Pt loading of 0.5 mg cm-2, the case of composite electrocatalyst of 0.1 mg cm-2 Pt-NWs and 0.4 mg cm-2 Pt/C presents the best catalytic activities which can be rationalized by enhanced electrochemical surface area and exchange current density in the catalyst layer. The effect of Nafion content is also evaluated and the results show that the optimal content of Nafion ionomer is 30 wt% using such a composite electrocatalyst in cathode catalyst layer.
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