Poly(butylene oxalate-co-terephthalate): A PBAT-like but rapid hydrolytic degradation plastic.

Concerns over worldwide plastic pollution have led to the development of biodegradable polyester materials with excellent physical and chemical properties through the copolymerization of poly(butylene oxalate) (PBOx). As a result, poly(butylene oxalate-co-terephthalate)s (PBOTs) with varying compositions, were prepared by incorporating aromatic units. Studies have indicated that PBOT-47 (with a 47% molar terephthalate), exhibits exceptional mechanical properties. With an elongation at break of 1160% and a tensile strength that remains above 30 MPa, similar to or even better than those of the commercial biodegradable plastic poly(butylene adipate-co-terephthalate) PBAT-47 (47% molar terephthalate). Moreover, the permeability coefficients of PBAT-47 for H2O, CO2 and O2 were 5.8, 50.6 and 5.6 times higher than that of PBOT-47, revealing the superior barrier properties of PBOT. Through experimental research and theoretical simulation, the mechanism of the copolymer hydrolysis was elucidated. The readily hydrolytic nature of the oxalate unit endows it with the capacity for rapid degradation, possessing the potential to be a short-term degradable material with physical properties similar to PBAT.

Synthesis of renewable furan-based phosphate and the superior flame retardancy in biodegradable polylactide.

Currently, it has long been considered a challenge to provide sustainable additives for polylactide (PLA) in green way to endow it excellent comprehensive properties. Given the flammability and unsatisfactory crystallization performance of PLA, a furan-based phosphate furfurylamine trimethylphosphate (FATMP) was synthesized from 2-furfurylamine and amino trimethylphosphonic acid by a simple hydration reaction, and the PLA/FATMP composites were prepared by melting blending process. The tensile performance, crystallization behaviors, flame retardancy, and flame-retardant mechanism received special attention. Results showed that the incorporation of only 3 wt% FATMP could indeed increase the LOI value of PLA from 19.8 to 27.3 %, and simultaneously acquired V-0 rating in the vertical burning test owing to the favorable synergistic effect between the vapor phase and the condensed phase. Additionally, the half-crystallization time of PLA was decreased from 12.4 to 5.1 mins with the addition of FATMP, which acted as a nucleating agent. More appealingly, the tensile performance of PLA/FATMP composites was also well maintained. In general, the PLA/FATMP composites we proposed could be promising candidates in application fields where favorable flame retardancy and crystallization ability are required.

Differential development and electrophysiological activity in cultured cortical neurons from the mouse and cynomolgus monkey.

In vitro cultures of primary cortical neurons are widely used to investigate neuronal function. However, it has yet to be fully investigated whether there are significant differences in development and function between cultured rodent and primate cortical neurons, and whether these differences influence the utilization of cultured cortical neurons to model pathological conditions. Using in vitro culture techniques combined with immunofluorescence and electrophysiological methods, our study found that the development and maturation of primary cerebral cortical neurons from cynomolgus monkeys were slower than those from mice. We used a microelectrode array technique to compare the electrophysiological differences in cortical neurons, and found that primary cortical neurons from the mouse brain began to show electrical activity earlier than those from the cynomolgus monkey. Although cultured monkey cortical neurons developed slowly in vitro, they exhibited typical pathological features-revealed by immunofluorescent staining-when infected with adeno-associated viral vectors expressing mutant huntingtin (HTT), the Huntington's disease protein. A quantitative analysis of the cultured monkey cortical neurons also confirmed that mutant HTT significantly reduced the length of neurites. Therefore, compared with the primary cortical neurons of mice, cultured monkey cortical neurons have longer developmental and survival times and greater sustained physiological activity, such as electrophysiological activity. Our findings also suggest that primary cynomolgus monkey neurons cultured in vitro can simulate a cell model of human neurodegenerative disease, and may be useful for investigating time-dependent neuronal death as well as treatment via neuronal regeneration. All mouse experiments and protocols were approved by the Animal Care and Use Committee of Jinan University of China (IACUC Approval No. 20200512-04) on May 12, 2020. All monkey experiments were approved by the IACUC protocol (IACUC Approval No. LDACU 20190820-01) on August 23, 2019 for animal management and use.

End-Chain Fluorescent Highly Branched Poly(l-lactide)s: Synthesis, Architecture-Dependence, and Fluorescent Visible Paclitaxel-Loaded Microspheres.

A facile method in combination of "grafting from" and "end-functionalization" was developed for the synthesis of fluorescent highly branched poly(l-lactide)s (PLLA-COU) via ring opening polymerization (ROP) and esterification end-capping. These resulting PLLA-COU with four kinds of architectures, including linear, star, linear-comb, and star-comb structures, were subjected to characterization and application as fluorescent visible paclitaxel-loaded microspheres. The mutual effects of architecture and end-groups on thermal and fluorescence properties, enzymatic degradation, and drug release behaviors were focused. Contrast to linear and star PLLA-COU, two comb-shaped analogues demonstrated higher fluorescence quantum yield, faster drug release, and lower enzymatic degradation rate. All the fluorescent microspheres could maintain fluorescence traceability. The fluorescent PLLA-COU displayed negligible toxicity and good biocompatibility. This work highlights that the fluorescent highly branched poly(l-lactide)s are properties-tailored and used as fluorescent visible drug delivery systems (DDS) for potential theranostic applications.

Development of biodegradable polyesters based on a hydroxylated coumarin initiator towards fluorescent visible paclitaxel-loaded microspheres.

In this work, we developed a facile end-functionalization method using hydroxylated coumarin to initiate the ring-opening polymerization of cyclic esters to synthesize a series of fluorescent biodegradable aliphatic polyesters with tailorable properties. The resulting fluorescent functionalized poly(l-lactide) (PLLA-COU), poly(ε-caprolactone) (PCL-COU) poly(δ-valerolactone) (PVL-COU) and poly(trimethylene carbonate) (PTMC-COU) were investigated to evaluate the dependence of fluorescence on the chemical structure and molecular weight of the materials. The differences in the electron withdrawing ability and the density of ester groups are responsible for the changes in the fluorescence quantum yield. Then, two representative biodegradable materials, namely, PLLA-COU and PCL-COU, were used to prepare fluorescent paclitaxel-loaded microspheres. During in vitro drug release, the release rate of the PCL-COU microspheres is dramatically faster than that of the PLLA-COU microspheres due to the difference in the material nature and their surface morphologies, possibly achieving a tunable degradation and release rate for the drug carriers. Fluorescent functionalized polyester microspheres can retain their fluorescence properties and emit bright blue light for fluorescence tracing during the degradation process. Biological evaluations showed that both fluorescent polyesters are devoid of any significant toxicity and have good biocompatibility. The results demonstrated that the obtained fluorescent polyesters are promising for use in traceable and controlled drug delivery with tunable drug release.

Basic Conception and Prospect of Rehabilitation Engineering and Assistive Technology / 中国康复理论与实践

The conceptions and characteristics of five basic terms,including rehabilitation engineering,assistive technology,assistive devices,assistive technology service and accessibility,were discussed briefly in this paper.The newest ISO 9999 Assistive Products for Per-sons with Disability-Classification and Terminology(sixth edition)published in 2016 was also introduced.In the future,assistive technolo-gy and rehabilitation engineering would be normalized as assistive health technology to carry out global cooperation(GATE),Priority Assis-tive Products List including 50 kinds of assistive products published by World Health Organization would be a model to make assistive poli-cy and project,assistive technology services would be standardized,assistive technology would continue to innovate,assistive technologies and therapy would be integrated,as well as assistive technologies and rehabilitation medicine,etc.

Differences of wound contraction and apoptosis in full-thickness burn wounds repaired with different artificial dermal stent in pigs / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the roles and differences of angiogenesis of different dermal scaffolds on wound contraction and apoptosis during full-thickness burn wound repair.</p><p><b>METHODS</b>Wounds were observed at different time after the collagen-sulfonated carboxymethyl chitosan porous scaffold or collagen-chitosan porous scaffold or acellular dermal matrix were respectively transplanted on wounds of full thickness burn with debridement in Bama miniature pigs. At the same time, vessels and myo-fibroblasts expressing α-smooth muscle action(α-SMA) and apoptosis in wounds of different time were detected in situ by immunohistochemical staining, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling. The burn wounds without any scaffold transplantation were studied as the control.</p><p><b>RESULTS</b>Wounds with different scaffolds transplantation were different from granulation wounds. Vessels expressing α-SMA had been increasing continuously in the wounds from 1 to 3 weeks after different scaffolds transplantation and decreased in wounds after epidermis had been grafted for 2 weeks on surface of the scaffolds transplanted on wounds for 2 weeks. Vessels expressing α-SMA were the most in the wounds with collagen-sulfonated carboxymethyl chitosan porous scaffold transplantation and the least in the control wounds without dermal scaffold at different time. Myo-fibroblasts expressing α-SMA was the least in the wounds with collagen-sulfonated carboxymethyl chitosan porous scaffold transplantation and the peak of expressions was on the 2nd week, however, the peak in the wounds with the other two scaffolds transplantation and in the control wound without dermal scaffold was on the 3rd week. Myo-fibroblasts expressing α-SMA was the most in the control wounds. Apoptosis had been increasing continuously in the transplantation wounds from 2 to 4 weeks after different scaffolds transplantation, however, apoptosis had begun to increase continuously from 3 to 4 weeks in the control wounds. Apoptosis was the most in the wounds with collagen-sulfonated carboxymethyl chitosan porous scaffold transplantation and the least in the control wounds without dermal scaffold from 3 to 4 weeks.</p><p><b>CONCLUSION</b>Sulfonated carboxymethyl chitosan can promote migration of reparative cells and angiogenesis, and it can repair full-thickness burn wound fast and well.</p>

Comparative study on repair of full-thickness burn wound with different artificial dermal stent in pigs / 中华整形外科杂志

<p><b>OBJECTIVE</b>To compare differences of angiogenesis among collagen- chitosan, collagen-sulfonated carboxymethyl chitosan porous scaffolds and acellular dermal matrix after these three different scaffolds with silicone membrane were transplanted on the wounds of full thickness burn, and the wound repair of different scaffolds with epidermis grafting on.</p><p><b>METHODS</b>Angiogenesis in different dermal scaffolds, the wound surface and epidermis survival were observed in 1, 2, and 3 weeks after the three different scaffolds were respectively transplanted on wounds of full thickness burn with debridement in 6 Bama miniature pigs (total 18 pigs in 3 groups). At the same time, CD34 positive signals (neo-forming microvessels) were detected by immunohistochemical staining. The wounds without any scaffold transplantation were studied as the control.</p><p><b>RESULTS</b>Angiogenesis had been fundamentally finished in 2 weeks after implantation of collagen- sulfonated carboxymethyl chitosan porous scaffold. And fundamental angiogenesis in collagen- chitosan porous scaffolds and acellular dermal matrix needed at least 3 weeks. Neo-forming micro-vessels perpendicular to wound beds with these three different scaffolds were more than those in the control wounds without scaffold. CD34 positive signals (neo-forming micro-vessels) were significantly higher in wounds at the second week than those in wounds at the first week. And those in wounds at the third week were significantly higher than those in wounds at the second week in all wounds with different scaffold transplantations and the control wounds. CD34 positive signals in the group of sulfonated carboxymethyl chitosan porous scaffold on the 1st, 2nd and 3rd week after the scaffold transplantation were significantly higher than those corresponding signals in the other three groups. Epidermis on the sulfonated carboxymethyl chitosan porous scaffold which had been transplanted on burn wound for 1 week could survive perfectly, however, epidermis on the collagen- chitosan porous scaffold or acellular dermal matrix could not survive until these two scaffolds had been transplanted on the burn wounds for at least 2 weeks.</p><p><b>CONCLUSIONS</b>These three different scaffolds could repair the full thickness skin defects caused by burn, and angiogenesis of sulfonated carboxymethyl chitosan porous scaffold is the best.</p>

The effect of thalidomide in preventing delayed nausea and vomiting induced by GP regimen of chemotherapy for non-small cell lung cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To observe the effect of thalidomide in preventing nausea and vomiting induced by emetogenic cisplatin (CDDP) chemotherapy in patients with advanced non-small cell lung cancer.</p><p><b>METHODS</b>This study was carried out as a prospective, randomized control clinical trial. 61 patients with advanced non-small cell lung cancer were scheduled to receive chemotherapy (gemcitabin 1000 mg/m(2) i.v. gtt d1, 8 and CDDP 75 mg/m(2) i.v. gtt d1, GP regimen). The patients were randomly divided into a treatment and control groups. All patients in both groups received ramosetron 0.3 mg intravenously (i.v.) and metoclopramide 20 mg intramuscularly (i.m.) 30 min prior to chemotherapy to prevent nausea and emesis on day 1. In the treatment group, addition of thalidomide (50 mg p.o. bid) were administered on days 1 to 5 after the start of chemotherapy.</p><p><b>RESULTS</b>Acute nausea was effectively controlled in 74.2% of the patients in the control group and in 90.0% of treatment group. Acute vomiting was effectively controlled in 90.3% of the patients in the control group and in 93.3% of treatment group. No statistically significant differences showed in effective control of acute nausea and vomiting between the 2 groups (P = 0.108; P = 1.000). Delayed nausea was effectively controlled in 19.4% of the patients in control group and in 56.7% in the treatment group. Delayed vomiting was effectively controlled in 48.4% of the patients in control group and 76.7% in treatment group. Statistically there was a significant differences in effective control of delayed nausea and vomiting between the 2 groups (P = 0.003, P = 0.023). Both antiemetic regimens were well tolerated, and no significant difference was observed in adverse events between the 2 groups (P > 0.05).</p><p><b>CONCLUSION</b>Our results demonstrate that thalidomide is highly effective in controlling delayed nausea and vomiting episodes in patients induced by moderately emetogenic chemotherapy. Moreover, no serious toxic effects are induced by this treatment.</p>

Tissue-engineering bone with ADSCs and coral scaffold for repairing of cranial bone defect in canine / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate the application of tissue-engineering bone with ADSCs (adipose-derived stem cells) and coral scaffold for repairing of cranial bone defect in canine.</p><p><b>METHODS</b>Autologous ADSCs isolated from canine subcutaneous fat were expanded, osteogenically induced, and seeded on coral scaffolds. Bilateral full-thickness defects (20 mm x 20 mm) of parietal bone were created (n = 7). The defects were either repaired with ADSC-coral constructs (experimental group) or with coral alone (control group). Radiological, gross, biomechanical and histological observations were done to evaluate the bone regeneration.</p><p><b>RESULTS</b>Three-dimensional CT scan showed that new bones were formed in the experimental group at 12 weeks after implantation, while coral scaffolds were partially degraded in the control group. By radiographic analysis at 24 weeks post-transplantation, it showed that an average repair percentage of each defect was (84.19 +/- 6.45)% in experimental group, and (25.04 +/- 18.82)% in control group (P < 0.01). The maximum compression loading was (73.45 +/- 17.26) N in experimental group, and (104.27 +/- 22.71) N in control group (P <0.01). Histological examination revealed that the defect was repaired by typical bone tissue in experimental group, while only minimal bone formation with fibrous connection in the control group.</p><p><b>CONCLUSIONS</b>The tissue-engineering bone with autologous osteogenic ADSCs and scaffold could successfully repair the cranial defects in canine models.</p>

Expression of survivin gene in apoptosis induced by dexamethasone in CEM cells / 中国当代儿科杂志

<p><b>OBJECTIVE</b>The precise mechanism of glucocorticoid-induced apoptosis has not yet been elucidated. Survivin, a member of the inhibitors of apoptosis protein family, correlates with inhibition of apoptosis, proliferation, angiogenesis and multiple drugs resistance. This study aimed to investigate the variation of the survivin gene expression in apoptosis induced by dexamethasone (Dex) in the human T-lineage acute lymphoblastic leukemia (ALL) cell line, CEM-WT cells.</p><p><b>METHODS</b>The logarithmically growing CEM cells cultured in vitro (cell density 2 x10(5)/mL) were exposed to 0.1, 0.5, 1, 5, and 10 microM Dex, then were collected 24, 48 and 72 hrs later. Untreated CEM cells were used as Controls. The cell viability was determined by trypan blue dye exclusion. Apoptosis was evaluated by morphology and flow cytometry. Survivin protein and gene were analyzed by Western Blot and RT-PCR.</p><p><b>RESULTS</b>CEM cells growth was obviously inhibited by 0.1, 0.5, 1, 5, and 10 microM Dex from 48 hrs. The inhibition effect was dose- and time-dependent. CEM cells treated with Dex (> or = 5 microM) exhibited typical apoptotic features. The apoptosis increased after 5 microM Dex treatment in a time-dependent manner, with the apoptosis percentage increasing from 14.9% (12 hrs) to 46.2% (48 hrs). Compared with that of the Control group, the expression of survivin protein was down-regulated, with the expression rate of 54.6%, 45.5%, 15.8% and 9.7% respectively at 12, 24, 48 and 72 hrs after 5 microM Dex treatment. 5 microM Dex treatment also resulted in a decrease of survivin mRNA expression. The survivin mRNA expression was 76.4%, 67.3%, 55.0%, 49.9%, 38.3% and 18.3% of the Control respectively at 6, 12, 24, 48 and 72 hrs after Dex treatment.</p><p><b>CONCLUSIONS</b>Apoptosis induced by Dex in CEM cells is associated with downregulation of the survivin expression.</p>

Effect of treatment of rosacea in females by Chibixiao Recipe in combination with minocycline and spironolactone / 中国结合医学杂志

<p><b>OBJECTIVE</b>To observe the clinical efficacy of Chibixiao Recipe (CBX) in combination with minocycline and spironolactone in treating rosacea in females.</p><p><b>METHODS</b>Sixty-eight women with rosacea were randomly assigned to the treated group (48 cases) and the control group (20 cases), both of which were treated with minocycline and spironolactone taken orally, but to the treated group, the Chinese herbal recipe, CBX was given additionally. Besides, cryotherapy with liquid nitrogen was applied to those with apparent capillary dilatation. The therapeutic course for both groups was 8 weeks. The levels of serum testosterone before and after treatment were determined by radioimmunoassay (RIA), and a 4-month follow-up was conducted.</p><p><b>RESULTS</b>In the treated group the cure-markedly effective rate was 87.5% and the recurrent rate was 6.5%, while in the control group, they were 45.0% and 41.2% respectively. Comparisons in the indexes between the two groups all showed significant difference (both P<0.01), with the cure-markedly effective rate higher, and the recurrent rate lower in the treated group. The serum level of testosterone got lowered in both groups ( P<0.05 and P<0.01), but the lowering in the treated group was more significant, showing significance when compared with that in the control group ( P<0.01).</p><p><b>CONCLUSION</b>CBX in combination with Western medicine has effect in treating rosacea superior to that of Western medicine alone, and could effectively reduce recurrent rate and the serum level of testosterone. female rosacea, testosterone, Chibixiao Recipe, minocycline, spironolactone</p>