RESUMEN
Chlorinated paraffins (CPs) are industrial chemicals that have potential adverse effects in the environment and on human health. This study investigated CPs in apiary environment, honeybees, and bee products from two rural areas of Beijing, China. The median concentrations of short-chain CPs (SCCPs) and medium-chain CPs (MCCPs) were 22 and 1.6 ng/m3 in the ambient air, 1350 and 708 ng/g dry mass (dw) in bees, 1050 and 427 ng/g dw in flowers, 37 and 54 ng/g in honey, 78 and 53 ng/g dw in bee pollen, 36 and 30 ng/g dw in soil, and 293 and 319 ng/g dw in bee wax. C10Cl6-7 and C14Cl7-8 dominated SCCPs and MCCPs in these samples, respectively. The concentrations and distributions of CPs in samples from apiaries located in the two regions varied. Long-range transportation of air masses was identified as an important source of CPs in apiaries. A close relationship between CPs in bees and the apiary environment indicated that bees could act as bioindicators for CP contamination in the environment. A human health risk assessment found that there were low risks for adults and children exposed to CPs through consumption of honey and pollen from the studied regions.
Asunto(s)
Hidrocarburos Clorados , Parafina , Niño , Abejas , Humanos , Animales , Parafina/análisis , Monitoreo del Ambiente , Hidrocarburos Clorados/análisis , China , BeijingRESUMEN
Release of phosphorus (P) from the sediments plays a critical role in the eutrophication of aquatic environments. Humic acids (HA), as the main form of carbon storage in the sediments, has essential impacts on the biogeochemical cycle of phosphorus in aquatic systems. Nevertheless, previous studies mainly concentrated on the competitive adsorption of HA solution and P on metal oxides and soils, with little attention paid to the effects of insoluble humic acids (IHA) on P sorption by and release from the sediments. Herein, an investigation on the rivers and lakes in Sichuan Province, China, found that there was a significantly positive correlation between the maximum P adsorption capacity (Qmax) of sediments and IHA contents (p < 0.01), but a significantly negative correlation between the zero equilibrium P concentration (EPC0) and IHA concentrations (p < 0.01). This indicated that IHA might have an inhibitory effect on the release of P from the sediments, which was verified by batch adsorption experiments and static incubation experiments. Adsorption experiments indicated that IHA can promote P adsorption by sediments. With the increase of IHA addition (from 0 to 20 mg/g) in the sediments, Qmax of sediments increased (from 0.516 to 0.911 mg/g), while EPC0 decreased greatly (from 0.264 to 0.005 mg/L). Increases in Fe (â ¢) bound-P, Al bound-P and humic bound-P caused by IHA were responsible for this promoting effect. Incubation experiments illustrated that IHA addition can efficiently inhibit P release from the sediments. After 32 days incubation, P concentration in the overlying water of control group (without IHA addition) was 0.651 mg/L, which was 13.29-40.69 times higher than those (0.016-0.049 mg/L) in the test groups (with 5 %-20 % IHA addition). The analysis of P species in sediments showed that transformation from loosely adsorbed-P and Fe (â ¢) bound-P to Al bound-P and humic bound-P was responsible for this inhibition of P release by IHA. This study demonstrated that IHA, differing from readily degradable or dissolved organic matter, have great inhibitory effects on internal P release, which provided a novel insight into the association between carbon burial and internal P release and even the management of water eutrophication.
Asunto(s)
Sustancias Húmicas , Contaminantes Químicos del Agua , Sustancias Húmicas/análisis , Monitoreo del Ambiente , Fósforo/análisis , Contaminantes Químicos del Agua/química , Sedimentos Geológicos/química , Lagos/análisis , Adsorción , China , Eutrofización , Agua/análisis , Carbono/análisisRESUMEN
Interleukin (IL)1ß is a pathogenic factor associated with the destruction of periodontal tissue in periodontitis. IL1ß processing is regulated by cytosolic machinery known as the inflammasome. Porphyromonas gingivalis infection and lipopolysaccharide (LPS) have an important role in the destruction of periodontal tissue in periodontitis. P. gingivalis infection and LPS have been reported to activate the NODlike receptor family pyrin domaincontaining protein 3 (NLRP3) inflammasome in human oral cells. Stem cell therapy exhibits antiinflammatory effects and stem cellconditioned culture media (SCM) shows similar beneficial effects. The present study tested the hypothesis that SCM inhibits activation of the inflammasome and protects human gingival epithelial cells (GECs) against LPSinduced inflammatory damage. Human GECs were treated with or without LPS plus SCM or control cell media. NLPR3 inflammasome components and inflammatory factors were measured by western blotting and immunofluorescence. The present study revealed that LPS induced an increase in the expression of inflammasome components, NLRP3, apoptosisassociated specklike protein containing a caspase recruitment domain (ASC) and caspase1. Coimmunoprecipitation revealed increased binding of NLRP3 and ASC, and immunofluorescence showed an increased colocalization of ASC and caspase1, suggesting that LPS stimulated assembly of the NLRP3 inflammasome. SCM inhibited the overexpression and assembly of NLRP3 inflammasome components induced by LPS. Furthermore, SCM blocked the increase in IL1ß production induced by LPS and inhibited the translocation of the inflammatory factor, NFκB, into the nuclei. Consequently, SCM protected cells against LPSinduced damage, as suggested by the recovery of disturbed Ecadherin staining pattern, which indicates a disruption in epithelial integrity. In conclusion, treatment with SCM may attenuate LPSinduced inflammatory damage in human GECs via inhibition of NLRP3 inflammasome activation, suggesting a potential therapeutic use for SCM.
Asunto(s)
Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Humanos , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Lipopolisacáridos/toxicidad , Medios de Cultivo Condicionados/farmacología , Células Epiteliales/metabolismo , Caspasa 1/metabolismo , Interleucina-1beta/metabolismoRESUMEN
Metal leaching is a key issue in cobalt-based catalysts/PMS systems, which results in the decline of catalytic ability and serious secondary pollution. Hence, a nitrogen-rich carbon framework with cobalt node (Co-NC-920) with low cobalt leaching was synthesized based on zeolite imidazole framework (ZIF) and g-C3N4 to activate peroxymonosulfate (PMS) for the degradation of carbamazepine (CBZ). With the restriction of nitrogen-rich carbon framework, cobalt can disperse better and form stable cobalt-nitrogen bonds, thus only 0.09 mg/L cobalt ions were leached in the solution. More than 99.9% of CBZ can be removed within 30 min of PMS addition. Further investigation revealed that 1O2, SO4â¢- and high-valent cobalt species were primarily responsible for CBZ degradation in the Co-NC-920/PMS system and different reactive oxygen species (ROS) were distinguished and quantified, finding 1O2 was predominant. The degradation process was realized by the coexistence of free radicals and non-free radicals. Moreover, CBZ degradation capacity of the catalyst was evaluated under the influence of common anions and in actual waterbody. Finally, the possible degradation pathways of CBZ were proposed and the toxicity of the intermediates was analyzed. This work provides a new approach for the synthesis of cobalt-based nitrogen-rich carbon catalysts with low leaching and high efficient.
Asunto(s)
Carbono , Cobalto , Carbono/química , Cobalto/química , Nitrógeno , Peróxidos/química , CarbamazepinaRESUMEN
PURPOSE: To analyze the general information,clinical symptoms, etiology of infection, and complications of oral and maxillofacial space infection in patients with different ages, in order to provide references for prevention of complications. METHODS: Three hundred and forty-eight patients with oral and maxillofacial space infection treated in the Oncology Department of Oral and Maxillofacial Surgery of the First Affiliated Hospital of Xinjiang Medical University were retrospectively analyzed from March 2007 to Feburary 2017. Statistical analysis was performed with SPSS 20.0 software package. RESULTS: All patients were divided into 2 groups. 152(43.68%) patients were senior and 196(56.32% ) patients were younger. In the two groups, male patients accounted for 59.69% in the younger group, 59.87% in the senior group. There was no significant difference. We also have found that label test and interval times of symptoms appeared to visit. There was no significant difference. 51.53% of the younger patients had negative bacterial culture results, which was significantly more than those of the senior groups. CONCLUSIONS: In patients with oral and maxillofacial space infection, senior patients had many similar clinical characteristics to younger patients, but senior patients suffered from more and severe complications.