Polyethylene glycol crosslinked decellularized single liver lobe scaffolds with vascular endothelial growth factor promotes angiogenesis in vivo

Background: Improving the mechanical properties and angiogenesis of acellular scaffolds before transplantation is an important challenge facing the development of acellular liver grafts. The present study aimed to evaluate the cytotoxicity and angiogenesis of polyethylene glycol(PEG) crosslinked decellularized single liver lobe scaffolds(DLSs), and establish its suitability as a graft for long-term liver tissue engineering. Methods: Using mercaptoacrylate produced by the Michael addition reaction, DLSs were first modified using N-succinimidyl S-acetylthioacetate(SATA), followed by cross-linking with PEG as well as vascular endothelial growth factor(VEGF). The optimal concentration of agents and time of the individual steps were identified in this procedure through biomechanical testing and morphological analysis. Subsequently, human umbilical vein endothelial cells(HUVECs) were seeded on the PEG crosslinked scaffolds to detect the proliferation and viability of cells. The scaffolds were then transplanted into the subcutaneous tissue of Sprague-Dawley rats to evaluate angiogenesis. In addition, the average number of blood vessels was evaluated in the grafts with or without PEG at days 7, 14, and 21 after implantation. Results: The PEG crosslinked DLS maintained their three-dimensional structure and were more translucent after decellularization than native DLS, which presented a denser and more porous network structure. The results for Young’s modulus proved that the mechanical properties of 0.5 PEG crosslinked DLS were the best and close to that of native livers. The PEG-VEGF-DLS could better promote cell proliferation and differentiation of HUVECs compared with the groups without PEG cross-linking. Importantly, the average density of blood vessels was higher in the PEG-VEGF-DLS than that in other groups at days 7, 14, and 21 after implantation in vivo. Conclusions: The PEG crosslinked DLS with VEGF could improve the biomechanical properties of native DLS, and most importantly, their lack of cytotoxicity provides a new route to promote the proliferation of cells in vitro and angiogenesis in vivo in liver tissue engineering.

Influence of Acupuncture on Autonomic Balance in Adult Tinnitus Patients:An Exploratory Study

Acupuncture is an alternative therapy for tinnitus in clinical practice.The mechanism by which acupuncture can alleviate tinnitus is still unknown.Autonomic nervous system was reported to be responsible for tinnitus.The aim of this study was to explore the effect of acupuncture on autonomic balance in adult tinnitus patients.Thirty patients were randomly assigned into either the deep acupuncture(DA)group or the shallow acupuncture(SA)group.Each patient received 6 acupuncture sessions(a-f phase)over three weeks.Measures of heart rate variability and Tinnitus Handicap Inventory(THI)were obtained at baseline and after the sixth acupuncture session in all patients.The results showed that the low frequency/high frequency(LF/HF)pattern was increased at b-f phase until the sixth acupuncture session when compared with that at the first acupuncture session in DA group.However,it continuously increased at b-f phase in SA group even at the sixth acupuncture session,which was not significantly different from that at the first acupuncture session.The decrease in THI in DA group was greater than that in SA group after 3-week treatment(P=0.043).Our preliminary study suggests three-week deep acupuncture can improve tinnitus symptoms in adult tinnitus patients,which may be related to the regulation of autonomic nervous system balance.

Preparation of 2D square-like Bi2S3-BiOCl heterostructures with enhanced visible light-driven photocatalytic performance for dye pollutant degradation

A series of Bi2 S3-BiOCI composites with two-dimensional(2 D) square-like structures were prepared via a two-step anion exchange route.X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), and diffuse reflectance spectra(DRS)were used to investigate the properties of the as-prepared Bi_2 S_3-BiOCI heterostructures. The coupling of BiOCl and Bi_2 S_3 induced enhanced photoabsorption efficiency and bandgap narrowing. A reactive brilliant red X-3 B dye was used as a contaminant to test the photocatalytic activity of the obtained Bi_2 S_3-BiOCl samples under visible light irradiation. The sample Bi_2 S_3-BiOCl with a mass ratio of 8:4 exhibited the highest photodegradation efficiency, which was six times higher than that of pure BiOCl. In addition, a mechanism for the enhancement of photocatalytic activity is proposed.

Clinical Features of Oxaliplatin-induced Hypersensitivity Reactions in Chinese Patients: A Retrospective Multicenter Analysis

Objective The characteristics of oxaliplatin-induced hypersensitivity reactions(HSRs)in Chinese patients were investigated to provide a reference for patients treated with oxaliplatin.Methods The study reviewed the records of patients who developed oxaliplatin-induced HSRs in 17 hospitals from May 2016 to May 2017.We collected and analyzed the basic information,history of oxaliplatin administration and premedication treatments,chemotherapy cycles,HSR symptoms,and the management and outcomes of these patients.Results Oxaliplatin-induced HSRs were recorded in 137 patients who had been treated with oxaliplatin-containing regimens.Five different chemotherapy regimens were applied.The median infusion cycle when oxaliplatin-induced HSRs occurred was 7,and HSRs occurred during or shortly after oxaliplatin infusion.Most of the patients experienced grade 1 or grade 2 HSRs with mild symptoms of pruritis(49.64%),flushing(46.72%),chest discomfort(26.28%),and urticaria(25.55%).The majority of the patients completely recovered from HSRs following treatment with antihistamines and dexamethasone.Seven patients completed chemotherapy with oxaliplatin after the symptoms resolved with proper management.Conclusion The results indicate that oxaliplatin-induced HSRs remain an important issue in safely and successfully fulfilling oxaliplatin-containing chemotherapy.Further studies are needed to analyze the risk factors and establish prophylaxis for such reactions.