Extracellular matrix (ECM) derived from decellularized tissues and organs has been used as a biological scaffold in a variety of pre-clinical and clinical applications. However, the lack of ...mechanical properties and shape controllability is a drawback. In contrast, synthetic polymers can be easily engineered with good mechanical performance, but they have limited biological functionality. In this study, we explored a new method to electrospun cartilage-derived extracellular matrix (cECM) and polycaprolactone (PCL) composite nanofibrous membranes. The cartilage is a compact tissue for which electrospinning is difficult. To overcome this problem, the cartilage was sliced into pieces, milled into powders, and digested into a looser structure. The cECM/PCL (mass ratio 50:50) hybrid nanofibers appeared to be smooth, thinner, and uniform with enhanced mechanical properties and wettability compared to the electrospun PCL. Meanwhile, the presence of cECM in the cECM/PCL nanofibrous membranes significantly promoted chondrocyte proliferation in vitro and facilitated cartilage regeneration in vivo. All these results indicate that the cECM/PCL nanofibrous membranes fabricated with good mechanical properties and biocompatibility may represent a promising scaffold for cartilage regeneration. Moreover, this work may offer a convenient and cost-effective method to synthesize ECM-based hybrid nanofibrous scaffolds for other tissue applications.
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•A new method to electrospun cECM/PCL hybrid nanofibrous scaffold was explored.•The cECM/PCL scaffold have enhanced mechanical properties and superior wettability compared with PCL alone.•the cECM/PCL scaffold promoted chondrocyte proliferation in vitro and facilitated cartilage regeneration in vivo.•This method represents a platform in which different decellularized tissues could be electrospun into nanofibers.
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(LCO) is a promising candidate for thermal barrier coatings (TBCs) due to that it provides better thermal insulation than yttria-stabilized zirconia (YSZ) does. In this work, a TBC LCO ...was produced by solution precursor plasma spraying (SPPS). After the solution precursors were prepared and the spraying parameters were optimized, the thermophysical properties and thermal shock performance of the coatings were tested. It was found that the SPPS coating with segmentation crack density of 6 mm
−1
had the porosities of about 33.5% at spray distances of 35 mm. The thermal conductivity of the SPPS coatings is 0.50–0.75 W·m
−1
·K
−1
, much lower than that of the atmospheric plasma spraying (APS) coatings (0.85–1.25 W·m
−1
·K
−1
). The thermal shock performance of the SPPS coatings reached 60 cycles, much better than the APS coatings. This improvement is due to the segmentation cracks in the coatings, which can improve strain tolerance and effectively relieve internal stress. This study provides reference significance for further research on thermal barrier coatings.
In tissue engineering research, there has recently been considerable interest in using electrospun biomimetic nanofibers of hybrids, in particular, from natural and synthetic polymers for engineering ...different tissues. However, phase separation between a pair of much dissimilar polymers might give rise to detrimental influences on both the electrospinning process and the resultant fiber performance. A representative natural-synthetic hybrid of gelatin (GT) and polycaprolactone (PCL) (50:50) was employed to study the phase separation behavior in electrospinning of the GT/PCL composite fibers. Using trifluoroethanol (TFE) as the cosolvent of the two polymers, observation of visible sedimentation and flocculation from dynamic light scattering analysis of the GT/PCL/TFE mixture both showed that phase separation does occur in just a few hours. This consequently led to gradually deteriorated fiber morphologies (e.g., splash, fiber bonding, and varied fiber size) over time during electrospinning GT/PCL. Quantitative analysis also indicated that the ratio of GT to PCL in the resultant GT/PCL fibers was altered over time. To address the phase separation related issues, a tiny amount (<0.3%) of acetic acid was introduced to improve the miscibility, which enabled the originally turbid solution to become clear immediately and to be single-phase stable for more than 1 week. Nanofibers thus obtained also appeared to be thinner, smooth, and homogeneous with enhanced performance in wettability and mechanical properties. Given the versatility and widely uses of the electrospun GT/PCL and other similar natural-synthetic hybrid systems in constructing tissue-engineered scaffolds, this work may offer a facile and effective approach to achieve finer and compositionally homogeneous hybrid nanofibers for effective applications.
Fibroblast activation protein (FAP) is higher expressed on cancer-associated fibroblasts (CAFs) in most malignant epithelial neoplasms, which is lower expressed in normal tissues. As a promising ...small molecular probe, FAP inhibitor (FAPI) shows the specific binding to FAP. This study aimed to explore a novel molecular probe
TcTc-HYNIC-FAPI targeting CAFs. The in vitro characteristics of the probe were also evaluated. The FAPI targeting FAP was designed, synthesized and conjugated with the chelator 6-hydrazinylnicotinic acid (HYNIC) for radiolabeling with
Tc. The radiolabeling yield, radiochemical purity and stability were evaluated by Instant thin-layer chromatography (ITLC) and High performance liquid chromatography (HPLC). Lipophilicity was performed by the distribution coefficient test. The binding and migration ability of the probe was assessed using the FAP transfected tumor cell line. The radiolabeling yield of
TcTc-HYNIC-FAPI was (97.29 ± 0.46) %. The radiochemical purity was more than 90% and kept stable until 6 h. The radioligand was shown as lower lipophilicity, of which logD7.4 value was - 2.38 Formula: see text 0.13. In vitro experiments, the results indicated that the probe showed binding properties, and inhibited the migration of tumor cells. The novel
TcTc-HYNIC-FAPI probe was successfully radiosynthesized and exhibited good radiochemical purity, stability and in vitro binding ability to tumor cells. The
TcTc-HYNIC-FAPI will be a promising SPECT/CT imaging probe.
Long segmental repair of trachea stenosis is an intractable condition in the clinic. The reconstruction of an artificial substitute by tissue engineering is a promising approach to solve this unmet ...clinical need. 3D printing technology provides an infinite possibility for engineering a trachea. Here, we 3D printed a biodegradable reticular polycaprolactone (PCL) scaffold with similar morphology to the whole segment of rabbits' native trachea. The 3D-printed scaffold was suspended in culture with chondrocytes for 2 (Group I) or 4 (Group II) weeks, respectively. This in vitro suspension produced a more successful reconstruction of a tissue-engineered trachea (TET), which enhanced the overall support function of the replaced tracheal segment. After implantation of the chondrocyte-treated scaffold into the subcutaneous tissue of nude mice, the TET presented properties of mature cartilage tissue. To further evaluate the feasibility of repairing whole segment tracheal defects, replacement surgery of rabbits' native trachea by TET was performed. Following postoperative care, mean survival time in Group I was 14.38 ± 5.42 days, and in Group II was 22.58 ± 16.10 days, with the longest survival time being 10 weeks in Group II. In conclusion, we demonstrate the feasibility of repairing whole segment tracheal defects with 3D printed TET.
Gizzerosine is a biogenic amine produced in fish meal drying process and posted higher mortality due to gizzard erosion in poultry than histamine. However, it is difficult to obtain gizzerosine and ...achieve sensitive practical detection due to its simple structure. Herein, a monoclonal antibody (mAb) specific to gizzerosine was generated based on the new structural design and a fluorescence immunosensor for sensitive and on-site detection of gizzerosine in feed was first established. Molecular modeling of the three-dimensional (3D) structure and surface electrostatic potential of gizzerosine indicated that the carbonyl group of gizzerosine hapten might affect the important sites of antigen-antibody interactions. The proposed structure was used to obtain the sensitive and specific mAb with IC50 of 3.88 ng/mL in indirect competitive ELISA which was approximately 100-fold lower than that of direct competitive ELISA. Considering the practical application scenarios, a fluorescence immunosensor based on microporous dry method integrated with independent quality control line was established to improve detection stability. Under the optimum conditions, the proposed immunosensor showed a good linear relationship from 1.10 to 19.78 ng/mL and provided a low detection limit of 50 ng/g which was approximately 80-fold lower than the maximum recommended amount (0.4 mg/kg) of gizzerosine in feed. The recoveries of 6 kinds of feed ranged from 83.1 % to 114.3 %, which was in good consistence with that of UHPLC–MS/MS. Overall, this work provides a fast, cost-effective and reliable on-site tool for rapid screening of gizzerosine residues in feed samples.
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•A novel hapten different from the original gizzerosine was designed for the first time.•A highly sensitive and specific anti-gizzerosine monoclonal antibody based on the novel hapten was prepared.•Relationship between antibody and hapten was studied by molecular modeling.•A fluorescence immunosensor was firstly developed for the on-site detection of gizzerosine.•The microporous dry method integrated with independent quality control line can be used for on-site detection.
Water resources are a fundamental natural and strategic economic resource and are closely related to high-quality economic and societal development. This paper uses the pilot implementation of the ...water resource tax reform to explore the impact of that reform on the green innovation and total factor productivity of enterprises. The study sample includes data for high water-consuming A-share listed enterprises in Shenzhen and Shanghai, China, from 2007 to 2021; the double-difference method was used for the analysis. Study findings indicate that replacing water resource fees with taxes significantly improves the green innovation level and total factor productivity of enterprises. Green innovation has a significant partial mediating effect between the water resource tax reform and total factor productivity. The water resource tax reform promotes green innovation in enterprises, enhancing total factor productivity. When considering different types of enterprise property rights, the economic effect of the water resource tax reform is more pronounced in non-state-owned enterprises, compared to state-owned enterprises. This paper provides empirical evidence for expanding the pilot scope of the water resource tax reform.
The aim of this longitudinal study was to examine seeking help from teachers as a mechanism mediating the relationship between achievement goals adopted by students early in the school year and their ...degree of behavioral and cognitive engagement in academic work almost 2 years later. A sample of 456 French Canadian students (215 boys; 240 girls; one unspecified) in Grade 7 (61%) and Grade 8 (39%) participated in the study. Results of structural equation modeling showed that mastery goals (approach and avoidance) were indirect predictors of both behavioral and cognitive engagement through seeking help from teachers. Performance goals (avoidance, but not approach orientation) were associated with cognitive engagement through help-seeking behaviors. Overall, these results suggest that achievement goals are key drivers of changes in academic engagement in early high school and that their contribution is explained by seeking help from teachers. Practical implications, limitations, and future research directions are discussed.
Cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is the standard treatment for patients with peritoneal cancer (PC). Following CRS-HIPEC, patients may also ...face risks caused by whole body hyperthermia. This study analyzed the incidence of temperature increases following CRS-HIPEC and identified the attendant risk factors.
A retrospective analysis was carried out among 458 patients who received CRS-HIPEC at the Fourth Hospital of Hebei Medical University between August 2018 and January 2021. The patients were divided into two groups according to post-HIPEC axillary temperature (≥38°C), with the demographics and the laboratory test results subsequently analyzed and compared, and the risk factors pertaining to temperature increases analyzed using univariate and multivariate logistic regression.
During CRS-HIPEC, 32.5% (149/458) of the patients with a temperature increase had an axillary temperature of not lower than 38°C, and 8.5% (39/458) of the patients with hyperpyrexia had an axillary temperature of not lower than 39°C. Female gender, gynecological malignancies, type of chemotherapy drug, increased postoperative neutrophil percentage, and a sharp drop in postoperative prealbumin were associated with the incidence of a temperature increase and axillary temperatures of >38°C. Among these factors, the type of chemotherapy drug was identified as an independent risk factor for a temperature increase during CRS-HIPEC.
By determining the risk factors pertaining to temperature increases during CRS-HIPEC, medical staff can identify the attendant risks among the patients and thus take preventive measures in a timely manner to maintain the patient's body temperature at a stable level. This suggests that further clinical research should be conducted to build a risk-prediction model for temperature increases following CRS-HIPEC.
Abstract
In this work the ability of pure surfactant Sodium Dodecyl Sulfate (SDS), Cetyltrimethyl Ammonium Bromide (CTAB) and their mixed surfactants for graphene dispersion in aqueous solution was ...investigated. The uniform and stable dispersion solution was obtained for graphene with the mixtures of SDS and CTAB at lower concentration as compared to the pure one. The SDS-based surfactants exhibited better dispersion as compared to CTAB-based surfactants due to smaller-sized graphene as was investigated via Zeta potential measurements. Zeta potential was utilized to characterize the colloidal stability of surface charges within the mixtures. The mixed surfactants utilized in the present study showed a better ability to disperse graphene and its derivatives and hence are well suited for practical applications.
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