Renewable Biomass Resources: from waste biomass to novel applications via green chemical technologies

Waste biomass as a resource represents an interesting opportunity that imbues the principles of green chemistry within the context of sustainability. Herein, potential routes for valorisation of currently low-value and/or underutilised biorenewable waste streams, namely: spruce wood chips; waste office paper; paper deinking residue (DIR), and; waste starch, using green chemical technologies are reported. Microwave-assisted low-temperature (<200 oC) pyrolysis was conducted on spruce wood chips, waste office paper and paper deinking residue (DIR) to afford three product lines: bio-oil (organic and aqueous phase); bio-char (microwave residue), and; gas. The application of the crude organic phase bio-oils as adhesives for aluminium to aluminium bonding was explored. Maximum tensile strengths, from approximately 2520 N (spruce wood chips) to 2300 N (waste paper) to 400 N (DIR), were observed. A synergistic and/or co-operative effect between various components of waste paper derived bio-oil on adhesive properties is postulated based on evaluation the results from liquid-liquid fractionation. This is the first reported application of bio-oils derived via low-temperature microwave processing for use as adhesives for metal-metal bonding. The first complete holistic characterization of low-temperature microwave-processed DIR is reported. The residue (78 wt.%) was characterized by solid-state 13C CP/MAS NMR and XRD, showing it was free from organic matter and primarily comprises calcite and kaolinite. The DIR-derived bio-oil gave the lowest adhesion properties (400 N) compared to paper and wood-derived bio-oil. The incorporation of expanded high amylose corn starch (HACS) and its propionates, with differing degree of substitution (DS), into potentially biodegradable hot melt adhesives (HMAs) comprising polyvinyl alcohol (PVOH) and glycerol was studied. The expansion process to form HMAs, surface area of HACS was increased from around 5 m2 g-1 to 176 m2 g-1, is beneficial towards Al adhesion (ca. 2.0 MPa) as compared to non-expanded HACS (ca. 1.1 MPa)

Antitumor activity of celastrol nanoparticles in a xenograft retinoblastoma tumor model

Zhanrong Li,1,* Xianghua Wu,1,* Jingguo Li,2 Lin Yao,1 Limei Sun,1 Yingying Shi,1 Wenxin Zhang,1 Jianxian Lin,1 Dan Liang,1 Yongping Li1 1State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, 2School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou, People&amp;#39;s Republic of China*These authors contributed equally to this workBackground: Celastrol, a Chinese herbal medicine, has shown antitumor activity against various tumor cell lines. However, the effect of celastrol on retinoblastoma has not yet been analyzed. Additionally, the poor water solubility of celastrol restricts further therapeutic applications. The goal of this study was to evaluate the effect of celastrol nanoparticles (CNPs) on retinoblastoma and to investigate the potential mechanisms involved.Methods: Celastrol-loaded poly(ethylene glycol)-block-poly(&amp;epsilon;-caprolactone) nanopolymeric micelles were developed to improve the hydrophilicity of celastrol. The 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulf-ophenyl)-2H tetrazolium monosodium salt (WST-8) assay was used to determine the inhibitory effect of CNPs on SO-Rb 50 cell proliferation in vitro. Immunofluorescence was used to evaluate the apoptotic effect of CNPs on nuclear morphology, and flow cytometry was used to quantify cellular apoptosis. The expression of Bcl-2, Bax, NF-&amp;kappa;B p65, and phospo-NF-&amp;kappa;B p65 proteins was assessed by Western blotting. A human retinoblastoma xenograft model was used to evaluate the inhibitory effects of CNPs on retinoblastoma in NOD-SCID mice. Hematoxylin and eosin staining was used to assess the apoptotic effects of CNPs on retinoblastoma.Results: CNPs inhibit the proliferation of SO-Rb 50 cells in a dose- and time-dependent manner with an IC50 of 17.733 &amp;micro;g/mL (celastrol-loading content: 7.36%) after exposure to CNPs for 48 hours. CNPs induce apoptosis in SO-Rb 50 cells in a dose-dependent manner. The expression of Bcl-2, NF-&amp;kappa;B p65, and phospo-NF-&amp;kappa;B p65 proteins decreased after exposure to CNPs 54.4 &amp;micro;g/mL for 48 hours. Additionally, the Bax/Bcl-2 ratio increased, whereas the expression of Bax itself was not significantly altered. CNPs inhibit the growth of retinoblastoma and induce apoptosis in retinoblastoma cells in mice.Conclusion: CNPs inhibit the growth of retinoblastoma in mouse xenograft model by inducing apoptosis in SO-Rb 50 cells, which may be related to the increased Bax/Bcl-2 ratio and the inhibition of NF-&amp;kappa;B. CNPs may represent a potential alternative treatment for retinoblastoma.Keywords: apoptosis, SO-Rb 50 cells, poly(ethylene glycol)-block-poly(&amp;epsilon;-caprolactone), nanopolymeric micelles, celastrol nanoparticles&amp;nbsp

Celastrol nanoparticles inhibit corneal neovascularization induced by suturing in rats

Zhanrong Li1, Lin Yao1, Jingguo Li2, Wenxin Zhang1, Xianghua Wu1, Yi Liu1, Miaoli Lin1, Wenru Su1, Yongping Li1, Dan Liang11State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, 2School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou, People&amp;#39;s Republic of ChinaPurpose: Celastrol, a traditional Chinese medicine, is widely used in anti-inflammation and anti-angiogenesis research. However, the poor water solubility of celastrol restricts its further application. This paper aims to study the effect of celastrol nanoparticles (CNPs) on corneal neovascularization (CNV) and determine the possible mechanism.Methods: To improve the hydrophilicity of celastrol, celastrol-loaded poly(ethylene glycol)-block-poly(&amp;epsilon;-caprolactone) nanopolymeric micelles were developed. The characterization of CNPs was measured by dynamic light scattering and transmission electron microscopy analysis. Celastrol loading content and release were assessed by ultraviolet-visible analysis and high performance liquid chromatography, respectively. In vitro, human umbilical vein endothelial cell proliferation and capillary-like tube formation were assayed. In vivo, suture-induced CNV was chosen to evaluate the effect of CNPs on CNV in rats. Immunohistochemistry for CD68 assessed the macrophage infiltration of the cornea on day 6 after surgery. Real-time quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay were used to evaluate the messenger ribonucleic acid and protein levels, respectively, of vascular endothelial growth factor, matrix metalloproteinase 9, and monocyte chemoattractant protein 1 in the cornea.Results: The mean diameter of CNPs with spherical shape was 48 nm. The celastrol loading content was 7.36%. The release behavior of CNPs in buffered solution (pH 7.4) showed a typical two-phase release profile. CNPs inhibited the proliferation of human umbilical vein endothelial cells in a dose-independent manner and suppressed the capillary structure formation. After treatment with CNPs, the length and area of CNV reduced from 1.16 &amp;plusmn; 0.18 mm to 0.49 &amp;plusmn; 0.12 mm and from 7.71 &amp;plusmn; 0.94 mm2 to 2.29 &amp;plusmn; 0.61 mm2, respectively. Macrophage infiltration decreased significantly in the CNP-treated corneas. CNPs reduced the expression of vascular endothelial growth factor, matrix metalloproteinase 9, and monocyte chemoattractant protein 1 in the cornea on day 6 after suturing.Conclusion: CNPs significantly inhibited suture-induced CNV by suppressing macrophage infiltration and the expression of vascular endothelial growth factor and matrix metalloproteinase 9 in the rat cornea.Keywords: celastrol, PEG-b-PCL nanopolymeric micelles, corneal neovascularization, macrophages, VEGF, MMP-

Association between gut microbiota and bone metabolism: Insights from bibliometric analysis

Gut microbiota has been reported to participate in bone metabolism. However, no article has quantitatively and qualitatively analyzed this crossing field. The present study aims to analyze the current international research trends and demonstrate possible hotspots in the recent decade through bibliometrics. We screened out 938 articles meeting the standards from 2001 to 2021 in the Web of Science Core Collection database. Bibliometric analyses were performed and visualized using Excel, Citespace, and VOSviewer. Generally, the annual number of published literatures in this field shows an escalating trend. The United States has the largest number of publications, accounting for 30.4% of the total. Michigan State University and Sichuan University have the largest number of publications, while Michigan State University has the highest average number of citations at 60.00. Nutrients published 49 articles, ranking first, while the Journal of Bone and Mineral Research had the highest average number of citations at 13.36. Narayanan Parameswaran from Michigan State University, Roberto Pacifici from Emory University, and Christopher Hernandez from Cornell University were the three professors who made the largest contribution to this field. Frequency analysis showed that inflammation (148), obesity (86), and probiotics (81) are keywords with the highest focus. Moreover, keywords cluster analysis and keywords burst analysis showed that “inflammation”, “obesity”, and “probiotics” were the most researched topics in the field of gut microbiota and bone metabolism. Scientific publications related to gut microbiota and bone metabolism have continuously risen from 2001 to 2021. The underlying mechanism has been widely studied in the past few years, and factors affecting the alterations of the gut microbiota, as well as probiotic treatment, are emerging as new research trends

Rapamycin Enhances Mitophagy and Attenuates Apoptosis After Spinal Ischemia-Reperfusion Injury

The spinal cord is extremely vulnerable to ischemia-reperfusion (I/R) injury, and the mitochondrion is the most crucial interventional target. Rapamycin can promote autophagy and exert neuroprotective effects in several diseases of the central nervous system. However, the impact of rapamycin via modulating mitophagy and apoptosis after spinal cord ischemia-reperfusion injury remains unclear. This study was undertaken to investigate the potential role of rapamycin in modulating mitophagy and mitochondria-dependent apoptosis using the spinal cord ischemia-reperfusion injury (SCIRI) mouse model. We found that rapamycin significantly (p &lt; 0.05) enhanced mitophagy by increasing the translocation of p62 and Parkin to the damaged mitochondria in the mouse spinal cord injury model. At the same time, rapamycin significantly (p &lt; 0.05) decreased mitochondrial apoptosis related protein (Apaf-1, Caspase-3, Caspase-9) expression by inhibiting Bax translocation to the mitochondria and the release of the cytochrome c from the mitochondria. After 24 h following SCIRI, rapamycin treatment reduced the TUNEL+ cells in the spinal cord ischemic tissue and improved the locomotor function in these mice. Our results therefore demonstrate that rapamycin can improve the locomotor function by promoting mitophagy and attenuating SCIRI -induced apoptosis, indicating its potential therapeutic application in a spinal cord injury

Analysis of influencing factors for conversion of laparoscopic cholecystectomy to open surgery

ObjectiveTo analyze the influencing factors for conversion of laparoscopic cholecystectomy to open surgery, and to provide a clinical reference for developing surgical procedures. MethodsA total of 278 patients receiving laparoscopic cholecystectomy in our hospital from January 2009 to December 2013 were analyzed. Among them, 31 patients were converted to open surgery during laparoscopic cholecystectomy, while the remaining 274 patients were not. The influencing factors for conversion to open surgery were investigated. The t test was applied in the comparison of continuous data, whereas the χ2 test was used for categorical data. The univariate logistic regression analysis was performed to investigate significant influencing factors, and the independent influencing factors were determined by multivariate logistic regression analysis. ResultsThe univariate analysis showed that sex (P=0.022), arteriosclerosis (P＜0.001), diabetes (P＜0.001), heart failure (P=0.002), previous upper abdominal surgery (P＜0.001), age (P＜0.001), body mass index (BMI) (P=0.003), gallbladder wall thickness (P＜0.001), the count of white blood cells (P＜0.001), and serum total bilirubin level (P=0.046) were significantly different between groups. The multivariate logistic regression analysis further showed that previous upper abdominal surgery (P＜0.001), sex (P=0.001), BMI (P=0.002), and the count of white blood cells (P=0.019) were independent influencing factors, among which previous upper abdominal surgery was the most significant one (OR=4.646， 95%CI: 2.012-10.729). ConclusionPrevious upper abdominal surgery, sex, BMI, and the count of white blood cells were independent influencing factors for conversion of laparoscopic cholecystectomy to open surgery. Careful evaluation of these factors before surgery would help to increase the operation efficacy, possessing an important clinical value

Research on the influence of outdoor wind environment on the operation characteristics of outdoor units of air conditioners in winter

Variable Refrigerant Volume multi connected air conditioning system is widely used in high-rise and super high-rise buildings because of its convenient control, flexible layout and installation and energy saving. However, for high-rise and super high-rise buildings, the outdoor wind environment has a significant impact on the installation, layout and operation performance of Variable Refrigerant Volume multi connected air conditioning system outdoor units. In this paper, the numerical simulation method is used to study the variation characteristics of inlet and exhaust temperature and speed of outdoor unit under different outdoor wind speed and wind direction in winter when the inclination angle of outdoor unit shutter of Variable Refrigerant Volume multi connected air conditioning system is 0 °, ± 30 °, ± 45 ° and ± 60 ° respectively. The results show that in winter, the air inlet and exhaust outlet should avoid the outdoor wind direction as much as possible. When there is no wind outside or the wind speed is 4m/s, the shutter angle should be maintained between 30 ° and 45 °. When the outdoor wind speed is 2m/s, the shutter angle should be maintained at about 30 °

Stability Analysis of Soil and Rock Mixed Slope Based on Random Heterogeneous Structure

Due to the complexity in the heterogeneous internal structure and interactions between rocks and soil, the slide of soil–rock mixed slope is usually more complex than that of a homogeneous soil slope. This paper investigated the stability of soil–rock mixed slopes with finite element method (FEM) based on random heterogeneous structure. An image-aided approach was used to generate the 2-D and 3-D digital rocks to ensure the morphology of digital rocks was similar with the real rocks. The 2-D and 3-D soil–rock mixed slopes were then generated by placing the digital rocks into the soil matrix. The generated heterogeneous structures of soil–rock mixed slope were imported into ABAQUS for numerical analysis. The effect of rock content, spatial distributions, material properties, and rock–soil interface on the stability of soil–rock mixed slopes were analyzed. Results show that the stability factor of the soil–rock mixed slope increases with the increase of rock content. The rocks can play a certain degree of antislide effect in the slope. The uneven spatial distribution of rocks has effect on the overall stability of soil–rock mixed slope. This effect is more significant when the rock content is moderate. Rocks distributed in the middle layer of the slope may improve the overall antisliding performance of the slope. The stability factor decreases with the increase of rock density. While the effect of rock elastic modulus on stability of soil–rock mixed slope is relatively limited. The contact condition at the soil–rock interface has effect on the overall stability of soil–rock mixed slope. It is recommended to properly determine the interface properties for stability analysis of soil–rock mixed slope