A ferritin-based nanoparticle displaying a neutralizing epitope for foot-and-mouth disease virus (FMDV) confers partial protection in guinea pigs.

BACKGROUND: Foot-and-mouth disease (FMD) is a devastating disease affecting cloven-hoofed animals, that leads to significant economic losses in affected countries and regions. Currently, there is an evident inclination towards the utilization of nanoparticles as powerful platforms for innovative vaccine development. Therefore, this study developed a ferritin-based nanoparticle (FNP) vaccine that displays a neutralizing epitope of foot-and-mouth disease virus (FMDV) VP1 (aa 140-158) on the surface of FNP, and evaluated the immunogenicity and protective efficacy of these FNPs in mouse and guinea pig models to provide a strategy for developing potential FMD vaccines. RESULTS: This study expressed the recombinant proteins Hpf, HPF-NE and HPF-T34E via an E. coli expression system. The results showed that the recombinant proteins Hpf, Hpf-NE and Hpf-T34E could be effectively assembled into nanoparticles. Subsequently, we evaluated the immunogenicity of the Hpf, Hpf-NE and Hpf-T34E proteins in mice, as well as the immunogenicity and protectiveness of the Hpf-T34E protein in guinea pigs. The results of the mouse experiment showed that the immune efficacy in the Hpf-T34E group was greater than the Hpf-NE group. The results from guinea pigs immunized with Hpf-T34E showed that the immune efficacy was largely consistent with the immunogenicity of the FMD inactivated vaccine (IV) and could confer partial protection against FMDV challenge in guinea pigs. CONCLUSIONS: The Hpf-T34E nanoparticles stand out as a superior choice for a subunit vaccine candidate against FMD, offering effective protection in FMDV-infected model animals. FNP-based vaccines exhibit excellent safety and immunogenicity, thus representing a promising strategy for the continued development of highly efficient and safe FMD vaccines.

Physical frailty intensifies the positive association of oral frailty with poor global cognitive function and executive function among older adults especially for females: a cross-sectional study.

BACKGROUND: Oral frailty is reported to increase the risk of new onset of mild cognitive impairment. Whereas, the association of oral frailty with cognition among older adults in both physical frail and non-physical frail status has not been sufficiently explored, and whether there are sex differences in the association is unclear. This study investigated the association of oral frailty and physical frailty with global cognitive function and executive function among older adults, as well as the sex differences in such association. METHODS: This cross-sectional study included 307 participants aged ≥ 60 years old from communities between June 2023 and August 2023, in Nanjing, China. Global cognitive function and executive function were assessed by using the Montreal Cognitive Assessment (MoCA) and Trail Making Tests A (TMT-A), respectively. Oral frailty was identified by the combination of natural tooth, Oral Frailty Index-8 (OFI-8), and oral diadochokinesis. Physical frailty was measured by using Fried phenotype model which contained 5 criteria: unintentional weight loss, weakness, exhaustion, slowness, and low physical activity. Multiple linear regression analyses for overall participants and stratified by sex and presence or absence of physical frailty were performed, respectively, to examine the association between oral frailty and cognitive functions. RESULTS: The median age of participants was 70 years old. The study included 158 (51.5%) females, 53 (17.3%) individuals with physical frailty, and 65 (21.2%) participants with oral frailty. After adjustment, the association between oral frailty and global cognitive function was observed in the physical frailty group (B = -2.67, 95% Confidence Interval [CI]: -5.27 to -0.07, p = 0.045) and the females with physical frailty (B = -4, 95% CI: -7.41 to -0.58, p = 0.024). Oral frailty was associated with executive function in overall participants (B = 0.12, 95% CI: 0.01 to 0.22, p = 0.037), physical frailty group (B = 23.68, 95% CI: 1.37 to 45.99, p = 0.038). In the adjusted models, oral frailty was significantly associated with executive function in all females (B = 0.21, 95% CI: 0.05 to 0.36, p = 0.009), in females without physical frailty (B = 0.19, 95% CI: 0.02 to 0.36, p = 0.027), and in females with physical frailty (B = 48.69, 95% CI: 7.17 to 90.21, p = 0.024). CONCLUSIONS: Physical frailty intensifies the positive association of oral frailty with poor global cognitive function and executive function among older adults, particularly among females. It is ponderable to consider sex differences and facilitate the management of physical frailty when it comes to promoting cognitive health based on the perspective of oral health among older adults.

The effectiveness of chin-down manoeuvre in patients with dysphagia: A systematic review and meta-analysis.

AIM: The chin-down posture is a widely used compensatory manoeuvre for patients with dysphagia. The aim of this study was designed to systematically measure the effectiveness of chin-down manoeuvre application. METHODOLOGY: We retrieved the PubMed, Web of Science, Embase, Cochrane Library, EBSCO, Medline, CNKI, WANFANG, VIP and SinoMed databases from inception to 30 August 2022. Raters independently screened literature according to inclusion and exclusion criteria. The quality of the included literature was evaluated, and data were extracted. The software Review Manager software 5.3 was used for statistical analysis. RESULTS: Fourteen studies with a total of 571 patients were included in this meta-analysis. The meta-analysis indicated that chin-down manoeuvre could significantly reduce the risk of aspiration (MD = -1.35, 95% CI [-2.25, -0.44], Z = 2.92, p < .01), decrease the chin angle (MD = -12.20, 95% CI [-14.61, -9.79], Z = 9.91, p < .001), shorten oral transit time (MD = -0.81, 95% CI [-1.20, -0.43], Z = 4.17, p < .001), reduce the maximum swallowing pressure at upper oesophageal sphincter (MD = -82.07, 95% CI [-112.77, -51.37], Z = 5.24, p < .001) and decrease pharyngeal residue. CONCLUSIONS: Existing evidence indicated that chin-down manoeuvre could reduce the risk of aspiration and pharyngeal residue, decrease the maximum swallowing pressure at UES. More large-sample, high-quality clinical trials are still needed in the future to further ascertain the results of this research.

Relationships among oral hygiene behavior, toothache, and depressive symptoms in Chinese older adults.

OBJECTIVES: The study aims to investigate the relationships among oral hygiene behavior, toothache, and depression among Chinese older adults. METHODS: We used data came from the 2018 wave of Chinese Longitudinal Healthy Longevity Survey (CLHLS). The Center for Epidemiologic Studies Depression Scale was used to evaluate depression. Binary logistic regression was performed to analyze the relationships among oral hygiene behavior, toothache, and depression. RESULTS: A total of 12,172 older adults were included in the study, of whom 27.2% had depression. Compared with those who did not brush their teeth daily, those who brushed their teeth at least once daily exhibited lower odds of having depressive symptoms (odds ratio [OR] = 0.86, 95% confidence interval [CI] = 0.77-0.97 versus OR = 0.81, 95% CI = 0.71-0.93). Compared with those who did not have toothache, those who had toothache over the past 6 months exhibited higher odds of having depression (OR = 1.49, 95% CI = 1.33-1.68). Living arrangement had a significant effect on the correlation between toothache and depression (p = 0.049), who lived alone and had toothache exhibited higher odds of having depressive symptoms. CONCLUSIONS: Oral hygiene behavior and toothache are associated with depression. Taking effective measures to maintain a daily toothbrushing pattern and reduce the occurrence of toothache may mitigate the risk of depression among older adults, especially among those living alone. CLINICAL RELEVANCE: The present study reports that the potential relationship between different oral hygiene behavior, toothache, and depressive symptoms.

Epidemiological characteristics of hand, foot, and mouth disease clusters during 2016-2020 in Beijing, China.

Hand, foot, and mouth disease (HFMD) is an infectious disease that usually occurs in children under 5 years and is caused by a group of enteroviruses. This study aimed to investigate the epidemiological characteristics of HFMD clusters from 2016 to 2020 in Tongzhou, Beijing, and explored the genetic evolution of CV-A6. The HFMD case information came from the Information System of China Center for Disease Control and Prevention (CDC), as well as the clusters information verification and on-site investigation by Tongzhou CDC. ARIMA model was applied to forecast HFMD clusters in 2020. Totally 440 HFMD clusters were reported during 2016-2020. The large peak of the clusters occurred in April-July, followed by a smaller peak in October-November during 2016-2019. However, in 2020, the two peaks disappeared. The main site of HFMD clusters was childcare facilities (65.0%) and mostly occurred in urban areas (46.1%). The detection rate of CV-A6 was the highest (36.1%), and cases with CV-A6 infection had the highest proportion of fever. The phylogenetic analysis based on CV-A6 VP1 gene showed that the predominant strains mainly located in Group F during 2016-2017, while changed into Group A during 2018-2020. HFMD clusters presented seasonality, mainly located in childcare facilities and urban areas, and CV-A6 was the major causative agent. Targeted prevention and control measures should be taken to reduce HFMD clusters.

Study on corrosion behavior of X80 steel under stripping coating by sulfate reducing bacteria.

BACKGROUND: At present, microorganism has been considered as important factors that threaten to buried pipelines with disbonded coatings. Aiming at the problem of unknown corrosion mechanism of sulfate-reducing bacteria (SRB), a series of studies have been carried out in this paper. Spectrophotometer and fluorescent labeling technology are used to study the growth and attachment of SRB in the simulated soil solution. The corrosion behavior of X80 pipeline steel with or without SRB was researched by electrochemical methods such as open circuit potential, dynamic potential polarization curve, and electrochemical impedance spectroscopy. The microscopic morphology of the corrosion products on the surface was observed with a scanning electron microscope (SEM), and the element content of the corrosion products on the surface of the sample after corrosion was observed using X-ray energy spectrum (EDS) analysis. RESULTS: The results showed that the growth and reproduction of SRB caused the pH of the soil simulated solution to increase, which may promote the corrosion of X80 steel. In addition, the cathode reaction of X80 steel in a sterile environment is the reduction of H+, and the main corrosion product is iron oxide. When the soil simulation solution contains SRB, the cathodic reaction is controlled by both H+ reduction and sulfide depolarization reactions, and FeS appears in the corrosion products. CONCLUSION: Although the life cycle of SRB is only about 14 days, the corrosion of X80 steel is greatly promoted by SRB, and even causes corrosion perforation, which will bring huge economic losses and serious safety hazards.

[Analysis of ALPL gene variant in a patient with infantile hypophosphatasia].

OBJECTIVE: To explore the genetic basis for a girl featuring bone and tooth mineralization disorder, premature deciduous teeth, rickets and short stature. METHODS: Genomic DNA was extracted and subjected to high-throughput whole exome sequencing. Suspected variants were confirmed by Sanger sequencing. Impact of potential variants was analyzed with bioinformatic software. RESULTS: The child was found to carry compound heterozygous missense variants of the ALPL gene, including c.1130C>T (p.A377V), a known pathogenic mutation inherited from her father, and c.1300G>A (p.V434M) inherited from her mother, which was unreported previously and predicted to be likely pathogenic based on standards and guidelines from the American College of Medical Genetics and Genomics (PM2+PM5+PP3+PP4). CONCLUSION: The compound heterozygous variants of c.1130C>T (p.Ala377Val) and c.1300G>A (p.Val434Met) of the ALPL gene probably underlay the disease in this child. Above finding has enriched the spectrum of ALPL gene variants.

Optimization of blocking conditions for fluorescent Western blot.

Blocking conditions are critical for reducing background and non-specific signals in Western blot (WB). For fluorescent WB, however, blockers may bring in additional autofluorescence, and optimal blocking conditions have been less well established. Here, the autofluorescence of Tween 20 is clarified, which is negligible when imaged wet, but could be significant when Tween 20 is dried on blots. In most situations, blocking with Tween 20 reduces background and/or improves specific signals. Systematical investigation of blocking conditions for fluorescent WB reveals that the autofluorescent background is determined by a combination of multiple factors including the blocker, the excitation/emission configuration, the membrane, and the H2O (wet or dry), varying case by case. The commonly used protein or polymer blockers (milk, bovine serum albumin, fish gelatin, and polyvinylpyrrolidone) each have unique advantages and disadvantages concerning the autofluorescence, the blocking efficiency, and the cost. 0.005%-0.02% sodium dodecyl sulphate can be included to reduce non-specific bands and background caused by non-specific binding of antibodies, however, at the cost of also impairing specific signals. For poorly-performing antibodies, a pre-test might be necessary to identify a suitable blocker. This work provides a reference for cost-effective blocking conditions for fluorescent WB.

Extraction, Purification, Structural Characteristics, Biological Activities and Pharmacological Applications of Acemannan, a Polysaccharide from Aloe vera: A Review.

: Aloe vera is a medicinal plant species of the genus Aloe with a long history of usage around the world. Acemannan, considered one of the main bioactive polysaccharides of Aloe vera, possesses immunoregulation, anti-cancer, anti-oxidation, wound healing and bone proliferation promotion, neuroprotection, and intestinal health promotion activities, among others. In this review, recent advancements in the extraction, purification, structural characteristics and biological activities of acemannan from Aloe vera were summarized. Among these advancements, the structural characteristics of purified polysaccharides were reviewed in detail. Meanwhile, the biological activities of acemannan from Aloe vera determined by in vivo, in vitro and clinical experiments are summarized, and possible mechanisms of these bioactivities were discussed. Moreover, the latest research progress on the use of acemannan in dentistry and wound healing was also summarized in details. The structure-activity relationships of acemannan and its medical applications were discussed. Finally, new perspectives for future research work on acemannan were proposed. In conclusion, this review summarizes the extraction, purification, structural characteristics, biological activities and pharmacological applications of acemannan, and provides information for the industrial production and possible applications in dentistry and wound healing in the future.

Fluorescent Nanoprobes with Oriented Modified Antibodies to Improve Lateral Flow Immunoassay of Cardiac Troponin I.

Performance of nanoprobes can often determine the detection level of Lateral immunochromatography. Traditional probes were limited by the quantity and orientation of antibodies, immune activity of the Fab region or binding strength between protein and substrate. This study developed a new efficient and robust technology to construct fluorescent nanoprobes with oriented modified antibodies, based on specific binding of the Fc region of antibody with streptococcal protein G (SPG) on the surface of polystyrene microspheres (MS) and subsequent covalent cross-linking at binding sites to firm them. Lateral flow immunoassay using these probes was applied for the detection of cardiac troponin I (cTnI). The significantly improved detection sensitivity demonstrated that antibody orientation on MS surfaces effectively enhanced immunological activities of probes compared with random immobilizing methods. Furthermore, performance evaluation results of lateral flow test strips met clinical requirements perfectly, including limit of detection (0.032 ng/mL), linearity ( R > 0.99), repeatability (CV < 10%), correlation ( R > 0.99), and heat aging stability. This research also employed heterophilic blocking reagent (HBR) to actively block redundant binding sites of SPG for the first time in order to eliminate false positive interferences, improving the sensitivity and precision of test results further.

Enhanced intracellular delivery and controlled drug release of magnetic PLGA nanoparticles modified with transferrin.

Owing to the presence of multidrug resistance in tumor cells, conventional chemotherapy remains clinically intractable. To enhance the therapeutic efficacy of chemotherapeutic agents, targeting strategies based on magnetic polymeric nanoparticles modified with targeting ligands have gained significant attention in cancer therapy. In this study, we synthesized transferrin (Tf)-modified poly(D,L-lactic-co-glycolic acid) nanoparticles (PLGA NPs) loaded with paclitaxel (PTX) and superparamagnetic nanoparticle (MNP) using a solid-in-oil-in-water solvent evaporation method, followed by Tf adsorption on the surface of NPs. The Tf-modified magnetic PLGA NPs were characterized in terms of particle morphology and size, magnetic properties, encapsulation efficiency and drug release. Furthermore, the cytotoxicity and cellular uptake of the drug-loaded magnetic PLGA NPs were evaluated in both MCF-7 breast cancer and U-87 glioma cells in vitro. We found that Tf-modified PTX-MNP-PLGA NPs showed the highest cytotoxicity effect and cellular uptake efficiency under Tf receptor mediation in both MCF-7 and U-87 cells compared to unmodified PLGA NPs and free PTX. The cellular uptake efficiency of Tf-modified magnetic PLGA NPs appeared to be facilitated by the applied magnetic field, but the difference did not reach statistical significance. This study illustrates that this proposed formulation can be used as one new alternative treatment for patients bearing inaccessible tumors.

[Preparation and release mechanism of tectorigenin intragastric floating sustained-release tablets].

To investigate the preparation technology and release mechanism of tectorigenin intragastric floating sustained-release tablets. The tablet was produced by wet granulation compression method, with hydroxypropyl methyl cellulose (HPMCK15M), cross-linked polyvinyl pyrrolidone (PVPP), octadecanol and sodium bicarbonate as excipient. The prescriptions were screened and optimized by orthogonal experimental design with in vitro floating capacity and drug release characteristics as the evaluation indexes. The optimization results were as follows: tectorigenin 33.3%, HPMCK15M 16.7%, PVPP 20.0%, octadecanol 13.3%, sodium bicarbonate 5%, and starch gel 10.7%. The prepared tablet can be floated within 10 s in the artificial gastric juice, lasting for 12 h in vitro, with a cumulative release rate of 70% in 10 h. The analysis of Rritger-Peppas equation showed that the sustained-release tablet had two advantages of both drug diffusion and skeleton dissolution. The tablet had good appearance and compressibility, as well as favorable floating capacity and drug release characteristics.

Late-Onset Nail Changes Associated with Hand, Foot, and Mouth Disease: A Clinical Analysis of 56 Cases.

OBJECTIVES: To investigate the development and clinical characteristics of nail changes in hand, foot, and mouth disease (HFMD). METHODS: A telephone survey was conducted with the parents of patients diagnosed with HFMD in the Fourth General Hospital of Nanhai from June to August 2013 to document nail changes within 3 months of diagnosis of HFMD. RESULTS: Valid survey results were obtained from 273 cases. Definitive nail changes were identified in 56 patients (20.5%). More boys (25.8%) than girls (10.6%) (p < 0.01) showed changes. The age distribution ranged from 1 to 5 years, and nail changes were rare in children younger than 1 year of age (p < 0.01). Nail changes were usually seen 1 to 2 months after the onset of HFMD and lasted for 1 to 8 weeks, most for approximately 4 weeks. Toenails or fingernails could be affected and the changes were more likely to occur synchronously. Fingernails were more commonly involved than toenails. When both fingernails and toenails were involved, this typically occurred synchronously. Although there were cases with all toenails and fingernails involved (16.1%), we did not encounter any instances involving 13 to 19 nails. The nail changes mainly presented as onychomadesis. Spontaneous recovery without special treatment was the course for all patients. No relapse or new nail involvement was identified. CONCLUSIONS: Nail change associated with HFMD usually occurs within 1 to 2 months after onset, mainly presents as onychomadesis, and is a self-limited process. Possible mechanisms are discussed.

Shape-shifting 3D protein microstructures with programmable directionality via quantitative nanoscale stiffness modulation.

The ability to shape-shift in response to a stimulus increases an organism's survivability in nature. Similarly, man-made dynamic and responsive "smart" microtechnology is crucial for the advancement of human technology. Here, 10-30 µm shape-changing 3D BSA protein hydrogel microstructures are fabricated with dynamic, quantitative, directional, and angle-resolved bending via two-photon photolithography. The controlled directional responsiveness is achieved by spatially controlling the cross-linking density of BSA at a nanometer lengthscale. Atomic force microscopy measurements of Young's moduli of structures indicate that increasing the laser writing distance at the z-axis from 100-500 nm decreases the modulus of the structure. Hence, through nanoscale modulation of the laser writing z-layer distance at the nanoscale, control over the cross-linking density is possible, allowing for the swelling extent of the microstructures to be quantified and controlled with high precision. This method of segmented moduli is applied within a single microstructure for the design of shape-shifting microstructures that exhibit stimulus-induced chirality, as well as for the fabrication of a free-standing 3D microtrap which is able to open and close in response to a pH change.

[Preparation of Oenothera biennis Oil Solid Lipid Nanoparticles Based on Microemulsion Technique].

OBJECTIVE: To study the preparation of Oenothera biennis oil solid lipid nanoparticles and its quality evaluation. METHODS: The solid lipid nanoparticles were prepared by microemulsion technique. The optimum condition was performed based on the orthogonal design to examine the entrapment efficiency, the mean diameter of the particles and so on. RESULTS: The optimal preparation of Oenothera biennis oil solid lipid nanoparticles was as follows: Oenothera biennis dosage 300 mg, glycerol monostearate-Oenothera biennis (2: 3), Oenothera biennis -RH/40/PEG-400 (1: 2), RH-40/PEG-400 (1: 2). The resulting nanoparticles average encapsulation efficiency was (89.89 ± 0.71)%, the average particle size was 44.43 ± 0.08 nm, and the Zeta potential was 64.72 ± 1.24 mV. CONCLUSION: The preparation process is simple, stable and feasible.

PDMS-TiO2 composite films combined with LC-MS/MS for determination of phospholipids of urine in non-small cell lung cancer patients with traditional Chinese medicine syndromes.

Lung cancer is one of the most common malignant tumors in China. Most patients are already in the mid to advanced stages during the consultation and the survival rate is less than 23 % with a poor prognosis. Therefore, effective dialectical diagnosis of advanced cancer can guide individualized treatment to improve survival. Phospholipids are the building blocks of cell membranes and abnormal phospholipid metabolism is associated with plentiful diseases. Most studies of disease markers use blood as a sample. However, urine covers extensive metabolites that are produced during the body's metabolic processes. Therefore, the study of markers in urine can be used as a complement to improve the diagnosis rate of marker diseases. Moreover, urine is characterized by high water content, high polarity, and high inorganic salt, therefore the detection of phospholipids in urine is challenging. In this study, an original Polydimethylsiloxane (PDMS)-titanium dioxide (TiO2) composite film for sample pre-treatment coupled with the LC-MS/MS method for the determination of phospholipids in the urine with high selectivity and low matrix effects was prepared and developed. The extraction process was scientifically optimized by the single-factor test. After systematic validation, the established method was successfully applied to the accurate determination of phospholipid substances in the urine of lung cancer patients and healthy subjects. In conclusion, the developed method has great potential for the development of lipid enrichment analysis in urine and can be used as a beneficial tool for cancer diagnosis and Chinese medicine syndrome typing.

Mussel-inspired anchoring for patterning cells using polydopamine.

This Article introduces a simple method of cell patterning, inspired by the mussel anchoring protein. Polydopamine (PDA), artificial polymers made from self-polymerization of dopamine (a molecule that resembles mussel-adhesive proteins), has recently been studied for its ability to make modifications on surfaces in aqueous solutions. We explored the interfacial interaction between PDA and poly(ethylene glycol) (PEG) using microcontact printing (µCP). We patterned PDA on several substrates such as glass, polystyrene, and poly(dimethylsiloxane) and realized spatially defined anchoring of mammalian cells as well as bacteria. We applied our system in investigating the relationship between areas of mammalian nuclei and that of the cells. The combination of PDA and PEG enables us to make cell patterns on common laboratorial materials in a mild and convenient fashion.

[Efficacy and adverse effets of nimotuzumab plus palitaxel liposome and carboplatin in the treatment for advanced non-small cell lung cancer].

OBJECTIVE: To evaluate the efficacy of nimotuzumab combined with palitaxel liposome and carboplatin (LP) regimen for treatment of advanced non-small cell lung cancer (NSCLC), and to observe the changes of tumor markers and toxicities in the treatment. METHODS Forty-one patients with advanced NSCLC were randomly divided into 2 groups: 21 patients in the observation group were treated with nimotuzumab (200 mg per week for 6 weeks), palitaxel liposome 160 mg/m2 and carboplatin (AUC = 6). 20 patients in the control group were given LP regimen. Each group completed two cycles of chemotherapy. The level of tumor markers (CEA, CYFR21-1 and NSE) and toxicities were checked at one week before and after the treatment. Thoracic CT examinations were taken before treatment and at the fourth week and eighth week after treatment. RESULTS: In the observation group, there were 2 cases of CR, 7 cases of PR, 9 cases of SD and 3 cases of PD. The objective response rate (RR) was 42. 9% in the observation group. In the control group, there were 1 case of CR, 6 cases of PR, 8 cases of SD and 5 cases of PD, with a RR of 35.0% in this group. There was no significant difference in the RR between the two groups (P = 0.751). The time to progression (TIP) was 6. 9 months in the observation group and 5. 7 months in the control group, with a significant difference (P = 0.027). The levels of NSE decreased significantly in both groups and showed a significant difference (P = 0.039). The levels of CEA and CYFRA21 in both groups were decreased after treatment, but did not show a significant difference before and after treatment, respectively. Except 3 cases had I-II skin toxicities on the faces in the observation group, there was no significant difference in toxicities between the two groups. CONCLUSION: Nimotuzmab combined with LP regimen shows a synergistic effect, can increase the efficacy and prolong TFP in advanced NSCLC patients. The toxicities are mild and tolerable.

In vitro biocompatiability and mechanical properties of bone adhesive tape composite based on poly(butyl fumarate)/poly(propylene fumarate)-diacrylate networks.

Polyfumarate has been considered as injectable and biodegradable bone cement. However, its mechanical and degradation properties are particularly important. Therefore, the current study aimed to develop the properties by compositing poly (butyl fumarate)-based networks with hydroxyapatite nano-powders. In this regard, the poly (butyl fumarate) (PBF) matrix composite was compared with different components by evaluating their composition, mechanical properties, hydrophilicity, and biodegradability. Furthermore, their bioactivity in the phosphate-buffered saline (PBS) and, via applying mouse embryo osteoblast precursor cells (MC3T3-E1), their cell interaction, including adhesion, proliferation, and in vitro cytotoxicity assay, were assessed. The addition of hydroxyapatite improved the mechanical strength and modulus of PBF matrix composite. The composite reinforced with 3 wt% hydroxyapatite showed a higher lap-shear strength (1.68 MPa) and bonding strength (4.30 MPa), a maximum compression strength at fracture (95.18 MPa), modulus (925.29 MPa), and compression strength at yield (31.43 MPa), respectively. Also, hydrophilicity and in vitro degradation of the composite were enhanced in the presence of hydroxyapatite. In this condition, after a period of immersion (52 weeks) in PBS, the weight loss rate, and degradation rate of the composite increased. The composite proliferation, adhesion, and toxicity of MC3T3-E1 cells improved in comparison to the PBF matrix composite. Accordingly, controllable strength and degradation of the composite, along with its proven biocompatibility, make the composite a candidate for the treatment of comminuted fractures.

Robust hemostatic bandages based on nanoclay electrospun membranes.

Death from acute hemorrhage is a major problem in military conflicts, traffic accidents, and surgical procedures, et al. Achieving rapid effective hemostasis for pre-hospital care is essential to save lives in massive bleeding. An ideal hemostasis material should have those features such as safe, efficient, convenient, economical, which remains challenging and most of them cannot be achieved at the same time. In this work, we report a rapid effective nanoclay-based hemostatic membranes with nanoclay particles incorporate into polyvinylpyrrolidone (PVP) electrospun fibers. The nanoclay electrospun membrane (NEM) with 60 wt% kaolinite (KEM1.5) shows better and faster hemostatic performance in vitro and in vivo with good biocompatibility compared with most other NEMs and clay-based hemostats, benefiting from its enriched hemostatic functional sites, robust fluffy framework, and hydrophilic surface. The robust hemostatic bandages based on nanoclay electrospun membrane is an effective candidate hemostat in practical application.