Photothermal therapy of xenografted tumor by carbon nanoparticles-Fe(II) complex.

Due to the unique structure, carbon nanomaterials could convert near-infrared (NIR) light into heat efficiently in tumor ablation using photothermal therapy (PTT). However, none of them has been applied in clinical treatment, because they have not been approved for clinical evaluations and the precise temperature control facility is scarce. In this study, we designed a temperature-responsive controller for PTT and used carbon nanoparticles-Fe(II) complex (CNSI-Fe) as photothermal conversion agent (PTA) for PTT of tumor in vitro and in vivo. CNSI-Fe was an innovative drug under the evaluations in clinical trials. CNSI-Fe showed excellent photothermal conversion ability in water to increase the water temperature by 40 °C within 5 min under irradiation of 808 nm laser at 0.5 W/cm2. The temperature was precisely controlled at 52 °C for both in vitro and in vivo tumor inhibition. CNSI-Fe with NIR irradiation showed higher tumor cell inhibition than CNSI. In tumor bearing mice, CNSI-Fe with NIR irradiation achieved an inhibition rate of 84.7 % and 71.4 % of them were completely cured. Mechanistically, CNSI-Fe under NIR irradiation induced the radical generation, oxidative damage and ferroptosis to kill tumor. In addition, CNSI-Fe showed good biosafety during PTT according to hematological, serum biological and histopathological examinations. These results indicated that the combination of chemotherapy and PTT provided higher antitumor efficiency using CNSI-Fe as PTA.

Porous Carbon Sponge from White-Rot Fungus Phanerochaete chrysosporium for the Removal of Oils and Organic Solvents.

Oil leakage incidentally occurs and leads to environmental disasters. Because of their porous and hydrophobic characteristics, graphene sponges are often studied as an oil adsorbent to repair oil spills at sea. Graphene materials are very expensive, and their biological toxicity has been given serious concerns; however, the easier preparation and eco-friendly, biomass-derived porous carbon materials can be used as an alternative to graphene materials. In this study, we prepared a porous carbon sponge (PCS) for oil and organic solvent removal by carbonizing white-rot fungus Phanerochaete chrysosporium, a fast-growing microorganism for the production of lignin-degrading enzymes and the environmental remediation. P. chrysosporium fungus balls were converted into black PCS by carbonization at high temperatures, where PCS was light (density of 56 g/L), hydrophobic (contact angle of 115°) and porous. According to the results of BET and XPS analysis, the surface area of PCS was 14.43 m2/g, and the carbon in PCS is mainly sp2 carbon. PCS could adsorb pure oils and organic solvents within seconds. The adsorption capacities of PCS were 20.7 g/g for gasoline, 30.1 g/g for peanut oil, 27.7 g/g for toluene, 18.5 g/g for dodecane, 32.5 g/g for chloroform, 27.1 g/g for tetrahydrofuran, 23.7 g/g for acetone and 13.7 g/g for ethanol. According to the reusability study, there was no obvious capacity loss after recycling up to 10 cycles. Our results indicated that white-rot fungi could be adopted as a cheap carbon resource for oil and organic solvent removal.

Particulate toxicity of metal-organic framework UiO-66 to white rot fungus Phanerochaete chrysosporium.

Metal-organic frameworks (MOF) are emerging materials with fantastic properties and wide applications. The release of metal ions from MOF materials is usually regarded as the origin of soluble MOF toxicity. However, whether the stable MOF particulates would induce environmental hazards is not clear. Herein, we aimed to reveal the particulate toxicity of MOF materials using the insoluble UiO-66 as the representative MOF and Phanerochaete chrysosporium as the model microorganism. UiO-66 nanoparticles (NPs) were synthesized by solvothermal method and their diameter was 68.4 ± 8.5 nm. UiO-66 NPs were stable in the culture system and the dissolution rate of 500 mg/L group was 0.26% after 14 d incubation. UiO-66 NPs did not affect the fungus growth according to the fresh weight increases and unchanged dry weights. Fungus mycelia kept even at concentrations up to 500 mg/L. Ultrastructural observation showed that UiO-66 NPs did not enter the fungal cells, but slightly destroyed the cell wall. UiO-66 NPs inhibited the laccase activity and promoted the activity of manganese peroxidase. The overall impact on the decomposition activity of P. chrysosporium was low in dye coloration test and sawdust degradation assay. Meaningful oxidative stress was aroused by UiO-66 NPs, as indicated by the decreases of catalase, glutathione, and total superoxide dismutase, and the increases of H2O2. Our results collectively suggested that the MOF particulates could induce mild mechanical damage to fungi and the toxicity was low comparing to other instable MOF materials.

Toxicity and activity inhibition of metal-organic framework MOF-199 to nitrogen-fixing bacterium Azotobacter vinelandii.

Metal-organic framework (MOF) materials with fantastic properties have found important applications in various areas. Learning the lessons from plastics and microplastics, it is urgent to investigate the environmental impacts of emerging materials to avoid potential pollution. However, the environmental toxicity and risks of MOF materials are seldom reported. Herein, we studied the toxicity and activity inhibition of MOF-199 to nitrogen-fixing bacterium Azotobacter vinelandii. MOF-199 significantly suppressed the growth of A. vinelandii and led to cell death at 40 mg/L. MOF-199 penetrated the cell wall and induced the shrinking of bacterial cells. MOF-199 reduced the nitrogen fixation activity of A. vinelandii at 40 mg/L by decreasing the gene nifH levels and inhibiting the Ca2+Mg2+-ATPase activity, which was further confirmed by the changes in oxidative phosphorylation related genes. Complete growth inhibition and activity loss of A. vinelandii occurred at 60 mg/L of MOF-199. The toxicological mechanism of MOF-199 to A. vinelandii was assigned to the oxidative stress, which occurred at 20 mg/L and higher. Both Cu2+ release and particulates themselves contributed to the toxicity of MOF-199 to A. vinelandii. These findings highlighted the environmental hazards and risks of MOF materials to nitrogen-fixing bacteria and nitrogen fixation in the biogeochemical cycle.

Trends of substance abuse behavior among adolescents in Guangdong Province, 2007-2016 / 中国学校卫生

Objective@#To analyle prevalence and trend of substance abuse behaviors among adolescents in Guangdong province and to provide theoretical evidence for effective interventions.@*Methods@#Data regarding smoking, drinking, drugs abuse from Adolescents Health Risk Behavior Survey in 2007, 2010, 2013 and 2016 were collected and comparatively analyzed.@*Results@#The incidences of tried smoking(27.37%), current smoking(8.32%), passive smoking(45.52%), current drinking(27.97%) and drug using(0.75%) in 2016 were lower than that in 2007(32.40%, 10.81%, 52.69%, 31.97%, 1.35%), and the average annual decrease rate were 1.89%, 2.95%, 1.64%, 1.50%, 6.75%, respectively(χ2=152.73, 92.50, 313.92, 46.48, 46.64, P<0.01). During the past decate, the incidences of current smoking in rural adolescents(12.02%, 10.64%, 9.99%, 10.10%) were significantly higher than that in urban adolescents(8.88%, 8.52%, 8.17%, 6.56%)(χ2=54.46, 26.62, 25.23, 100.43, P<0.01); the incidences of current drinking in urban adolescents(33.57%, 30.37%, 35.76%, 30.46%) were significantly higher than that in rural adolescents(30.97%, 28.48%, 28.47%, 25.32%)(χ2=16.71, 10.13, 153.47, 81.76, P<0.01); the incidence of current drinking was the highest among college students in each monitoring year(47.71%, 41.76%, 42.36%, 37.77%)(χ2=583.37, 681.25, 610.04, 729.02, P<0.01); the incidence of current smoking was the highest among vocational school students in each monitoring year(16.36%, 17.00%, 14.90%, 16.71%)(χ2=256.45, 515.61, 339.63, 742.52, P<0.01); In addition to the incidence of drug abuse was the highest among college students in 2010(2.02%), vocational school students were the highest in other years(χ2=66.92, 34.38, 23.08, 20.55, P<0.01).@*Conclusion@#Smoking and drug abuse among adolescents in Guangdong showed a declining trend by years, as well as the prevalence of drinking behavior. Strengthened intervention should be targeted on smoking behavior among rural students, drinking behavior among urban students, and smoking behavior and drug abuse among vocational school students.