Mechanochemistry Milling of Waste Poly(Ethylene Terephthalate) into Metal-Organic Frameworks.

Converting poly(ethylene terephthalate) (PET) into metal-organic frameworks (MOFs) has emerged as a promising innovation for upcycling of waste plastics. However, previous solvothermal methods suffer from toxic solvent consumption, long reaction time, high pressure, and high temperature. Herein, a mechanochemical milling strategy was reported to transform waste PET into a series of MOFs with high yields. This strategy had the merits of solvent-free conditions, ambient reaction temperature, short running time, and easy scale-up for large-scale production of MOFs. The as-prepared MOFs exhibited definite crystal structure and porous morphology composed of agglomerated nanoparticles. It was proven that, under mechanochemical milling, PET was firstly decomposed into 1,4-benzenedicarboxylate, which acted as linkers to coordinate with metal ions for forming fragments, followed by the gradual arrangement of fragments into MOFs. This work not only promotes high value-added conversion of waste polyesters but also offers a new opportunity to produce MOFs in a green and scalable manner.

Systematic analysis of critical genes and pathways identified a signature of neuropathic pain after spinal cord injury.

Spinal cord injury (SCI) damages sensory systems, producing chronic neuropathic pain that is resistant to medical treatment. The specific mechanisms underlying SCI-induced neuropathic pain (SCI-NP) remain unclear, and protein biomarkers have not yet been integrated into diagnostic screening. To better understand the host molecular pathways involved in SCI-NP, we used the bioinformatics method, the PubMed database and bioinformatics methods to identify target genes and their associated pathways. We reviewed 2504 articles on the regulation of SCI-NP and used the text mining of PubMed database abstracts to determine associations among 12 pathways and networks. Based on this method, we identified two central genes in SCI-NP: interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α). Adult male Sprague-Dawley rats were used to build the SCI-NP models. The threshold for paw withdrawal was significantly reduced in the SCI group, and TLR4 was activated in microglia after SCI. Enzyme-linked immunosorbent assay（ELISA) analysis of TNF-α and IL-6 levels was significantly higher in the SCI group than in the sham group. Western blot showed that expressions of the TLR4/MyD88/NF-κB inflammatory pathway protein increased dramatically in the SCI group. Using the TLR4 inhibitor TAK-242, the pain threshold and expressions of inflammatory factors and proteins of the proteins of the inflammatory signal pathway were reversed, TLR4 in microglia was suppressed, suggesting that SCI-NP was related to neuroinflammation mediated by the TLR4 signalling pathway. In conclusion, we found that TNF-α and IL-6 were the neuroinflammation-related genes involved in SCI-NP that can be alleviated by inhibiting the inflammatory pathway upstream of the TLR4/MyD88/NF-κB inflammatory pathway.

Xuebijing Injection () increases early survival rate by alleviating pulmonary vasopermeability in rats subjected to severe burns.

OBJECTIVE: To investigate the effects of Xuebijing Injection (, XBJ) on survival rate and pulmonary vasopermeability in a rat model of severe scald injury. METHODS: Rats were divided into two experiments: experiment 1 was monitored for 12 h post-injury for survival analysis after severe burns; in experiment 2, rats were killed for determination of pulmonary vascular permeability and pro-inflflammatory mediators. In both experiments, rats were subject to third-degree 50% total body surface area (TBSA) burns or sham injury followed by XBJ or normal saline (NS) treatment. In addition, rat pulmonary microvascular endothelium cells (PMECs) were pretreated with either XBJ or phosphate buffer saline (PBS), and then subjected to sham serum or scald serum stimulation for 2 or 6 h, followed by transwell examination for the permeability of PMECs. Meanwhile, pro-inflflammatory mediators in PMECs culture supernatant were also investigated. RESULTS: The average survival time in the scald+XBJ group was 582.1±21.2 min, which was signifificantly longer than that in the scald + NS group (345.8±25.4 min, P<0.01). Plasma levels of tumor necrosis factor-alpha (TNF-α), E-selectin, interleukin-6 (IL-6), vascular permeability and water content of lung tissues were signifificantly increased in animals after severe burns (P<0.01). However, administration of XBJ signifificantly decreased these levels in plasma and lung tissue. In in vitro cell experiments, XBJ markedly attenuated permeability in PMECs monolayer and reduced the levels of TNF-α, IL-6 and soluble E-selectin after stimulation with scald serum (P<0.01). CONCLUSIONS: XBJ increases early survival rate by alleviating pulmonary vasopermeability and inhibiting pro-inflflammatory mediators in rats subjected to lethal scald injury. XBJ may be a potent drug in treatment of severe burns.

The effects of ulinastatin on systemic inflammation, visceral vasopermeability and tissue water content in rats with scald injury.

BACKGROUND: The aim of this study was to examine whether administration of ulinastatin inhibits pro-inflammatory mediators and ameliorate visceral vasopermeability both in a rat model of major burn, and also in rat cultured endothelial cells stimulated with permeability-evoking mediators. METHODS: Plasma levels of tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), myeloperoxidase (MPO), microvascular permeability, and water content of organ tissues were evaluated in a rodent model of a 55% TBSA full-thickness scald injury. Microvascular permeability was also evaluated with a cultured pulmonary microvascular endothelial cells (PMECs) monolayer after stimulation with trypsin, bradykinin, histamine, prostaglandin E2 and burn serum. RESULTS: We found that the plasma levels of TNF-α, CRP, MPO, vascular permeability and water content of heart, lung, kidney, and small intestine tissues were significantly increased in animals after scald injury, and administration of ulinastatin lowered the levels TNF-α, CRP, MPO, vascular permeability and water content of those organ tissues. In vitro, ulinastatin lowered the levels of TNF-α, interleukin-6 (IL-6) and attenuated permeability in PMEC monolayers after being stimulated with burn serum or trypsin, but not by bradykinin, histamine or prostaglandin E2. CONCLUSIONS: These results indicate that ulinastatin attenuates the systemic inflammatory response and visceral vasopermeability both in vivo and vitro, and may serve as a therapeutic agent for prevention of systemic inflammatory response and leakage of fluid into tissue after major burn.

[The protective effects of carbachol on visceral ischemia-induced lipid peroxidation injury in rats with sepsis].

OBJECTIVE: To investigate the effect of carbachol (CAR) on visceral perfusion and lipid oxidation injury in rats with sepsis. METHODS: Sixty-four Sprague-Dawley (SD) rats received cecal ligation and puncture (CLP) surgery, and they were divided randomly into two groups: septic model group (CLP group, n=32) and septic model with CAR-treatment group (CAR group, n=32). CAR (10 microg/kg, CAR group) or normal saline (CLP group) was immediately injected into penial vein. Sixteen animals in each group were used to observe the mortality rates 12 hours and 24 hours after CLP, and the remaining rats for measurement of variables of blood and tissue. At the 18 hours after CLP, the mean arterial pressure (MAP), the blood flow (BF) of liver, kidney and jejunum, the plasma levels of alanine aminotransferase (ALT) and creatinine (Cr) were measured. Animals were sacrificed after the aforementioned determinations, and specimens of liver, kidney and jejunum were harvested for evaluation of malondialdehyde (MDA), xanthine oxidase (XOD), and assessment of tissue water content (ratio of dry to wet weight) of those organs . The activity of diamine oxidase (DAO) in jejunal tissue was detected. RESULTS: The mortality rates of 12 hours and 24 hours of CAR group were 25.0% (4/16)and 50.0% (8/16) respectively, all significantly lower than those of CLP group [37.5% (6/16) and 75%(12/16), both P<0.05]. CAR treatment did not result in significant statistical difference in the levels of MAP compared with CLP group at 18 hours after CLP (P>0.05), but led to significant increases in BF of CAR group in liver, kidney and jejunum compared with those of CLP group (all P<0.05). The levels of XOD and MDA, as well as the tissue water content were significantly lower in CAR group than CLP group in kidney and jejunum (all P<0.05). The parameters of organ function were significantly different in CAR group compared with CLP group [ALT: (64.3+/- 8.3) U/L vs. (81.5+/-7.9) U/L, Cr: (96.4+/-7.0) micromol/L vs. (117.1+/-6.7) micromol/L, DAO: (0.20+/- 0.04) U/L vs. (0.12+/-0.03) U/L, all P<0.05]. CONCLUSION: The results indicate that CAR promotes visceral perfusion, inhibits lipid peroxidation production and alleviates visceral edema and dysfunction in rats with sepsis.

[The effects of electro-acupuncturing at Zusanli point on intestinal proinflammatory factors, diamine oxidase and tissue water content in rats with sepsis].

OBJECTIVE: To investigate the protective effect of electro-acupuncturing (EA) at Zusanli point on sepsis induced ischemic and oxygen free radical intestinal injury in rats with sepsis. METHODS: Thirty-two male Wistar rats were used to reproduce sepsis by cecal ligation and puncture (CLP), and they were randomly divided into four groups (each n=8): CLP+EA (CLP/EA), CLP+sham EA (CLP/SEA), vagotomy+CLP+SEA (VA/CLP/SEA) and vagotomy+CLP+EA (VA/CLP/EA). Zusanli point was electro-acupunctured with constant voltage (2-100 Hz,2 mA for 30 minutes) immediately after CLP surgery. Abdominal vagotomy was performed in rats in VA/CL/SEA and VA/CLP/SEA groups. Six hours after CLP, the mucosal blood flow of jejunum (JMBF) was measured. Animals were sacrificed after 6 hours and specimens of jejunum were harvested for evaluation of malondialdehyde (MDA), xanthine oxidase (XOD), diamine oxidase (DAO) and assessment of the water content (WCR). RESULTS: JMBF and the activity of DAO of CLP/EA group were markedly higher, and the levels of XOD, MDA and WCR in jejunal tissue were obviously lower than those of CLP/SEA group (all P<0.05). The levels of JMBF and DAO of the VA/CLP/SEA group and VA/CLP/EA group were significantly lower, and XOD, MDA and WCR obviously higher than those of the CLP/EA group ( all P<0.05 ). There were no statistically differences in all above measurements between the VA/CLP/EA group and the VA/CLP/SEA group (all P>0.05). CONCLUSION: The results indicate that EA at Zusanli point obviously increased JMBF and DAO, and alleviated tissue edema and insult of intestinal mucosa. Vagotomy could weaken or eliminate the effects of EA. It is suggested that cholinergic anti-inflammatory pathway is one of the main mechanisms of intestinal protective effect of EA at Zusanli point.