[Pollution Characteristics and Health Risk Assessment of VOCs in Areas Surrounding a Petrochemical Park in Shanghai].

To investigate the pollution characteristics of volatile organic compounds (VOCs) in the vicinity of a petrochemical park, the composition and concentration of VOCs was successively monitored by application of a gas chromatography-flame ionization detector in the residential area surrounding a petrochemical park in Shanghai in October 2017. Moreover, the maximum incremental reactive method was employed to estimate the O3-formation potential contributed by VOCs, and health risks were assessed. Results showed that during the observation period, TVOCs concentrations ranged from 16.4 µg·m-3 to 1947.8 µg·m-3 with an average concentration of 40.7 µg·m-3, whereas the average proportions of alkanes, alkene/alkynes, and aromatic hydrocarbons were 66.2%, 25.9%, and 7.9%, respectively. The diurnal variation of total VOCs concentration showed a monomodal change, with a peak concentration of 127.9 µg·m-3 at 07:00, whereas the TVOCs had an average ozone formation potential (OFP) of 249.7 µg·m-3. Analysis of OFP indicated that trans-2-butene and ethylene were the most important species in ozone production with accountabilities for total OFP of 153.4 µg·m-3. Propylene, trans-2-butene, and ethylene were the key active species. Furthermore, health risk assessments revealed that no significant health risks had been caused by hexane, benzene, toluene, ethylbenzene, o-xylene, and m-xylene.

A combined experimental and computational study of novel nanocage-based metal-organic frameworks for drug delivery.

Three new metal organic frameworks (MOFs) with chemical formulae [(CH3)2NH2] [Sm3(L1)2(HCOO)2(DMF)2(H2O)]·2DMF·18H2O (1), [Cu2(L2)(H2O)2]·2.22DMA (2) and [Zn2(L1)(DMA)]·1.75DMA were synthesized and structurally characterized. 1 and 2 show a classical NbO-like topology and have two types of interconnected cages. 3 exhibits an uncommon zzz topology and has two types of interconnected cages. These MOFs can adsorb large amounts of the drug 5-fluorouracil (5-FU) and release it in a progressive way. 5-FU was incorporated into desolvated 1, 2 and 3 with loadings of 0.40, 0.42, and 0.45 g g(-1), respectively. The drug release rates were 72%, 96% and 79% of the drug after 96 hours in 1, 120 hours in 2 and 96 hours in 3, respectively. Grand Canonical Monte Carlo (GCMC) simulations were performed to investigate the molecular interactions during 5-FU adsorption to the three novel materials. The GCMC simulations reproduced the experimental trend with respect to the drug loading capacity of each material. They also provided a structural description of drug packing within the frameworks, helping to explain the load capacity and controlled release characteristics of the materials. 5-FU binding preferences to 1, 2 and 3 reflect the diversity in pore types, chemistry and sizes. The calculated drug load is more related to the molecular properties of accessible volume Vacc than to the pore size.

Repeated treatment with rituximab based on the assessment of peripheral circulating memory B cells in patients with relapsing neuromyelitis optica over 2 years.

OBJECTIVE: To evaluate the efficacy and safety of repeated rituximab treatment based on the assessment of peripheral circulating memory B cells over 24 months in patients with relapsing neuromyelitis optica (NMO). DESIGN: Prospective open-label study. SETTING: Institutional referral center for multiple sclerosis. Patients Thirty patients with relapsing NMO or NMO spectrum disorder. Intervention Treatment protocol of rituximab consisted of an induction therapy (375 mg/m² once weekly for 4 weeks or 1000 mg infused twice, with a 2-week interval between the infusions) followed by maintenance therapy. The maintenance therapy was repeated treatment with rituximab (375 mg/m², once) whenever the frequency of reemerging CD27+ memory B cells was more than 0.05% in peripheral blood mononuclear cells by flow cytometric analysis. MAIN OUTCOME MEASURES: Annualized relapse rate, disability (Expanded Disability Status Scale score), anti-aquaporin 4 antibody level, and safety of rituximab treatment. RESULTS: Of 30 patients, 28 showed a marked reduction in relapse rate while taking rituximab over 24 months. The relapse rate was reduced significantly, by 88%, and 70% of patients became relapse-free over 24 months. Disability either improved or stabilized in 97% of patients. Anti-aquaporin 4 antibody levels declined significantly following treatment with rituximab, consistent with the clinical response and the effect on CD27+ memory B cells. Repeated treatment with rituximab was generally well tolerated, and no clinically relevant adverse event leading to discontinuation of treatment was observed. CONCLUSION: Repeated treatment with rituximab appeared to produce consistent and sustained efficacy over 24 months with good tolerability in patients with NMO.