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Electronic cigarette (e-cigarette) use has been linked to recent acute lung injury case clusters in over 2000 patients and dozens of deaths in the United States, however, the mechanism leading to lung injury is not certain although ultrafine particles, heavy metals, volatile organic compounds, and other harmful ingredients have been implicated. To systematically evaluate e-cigarette toxicity, we generated e-cigarette aerosols by varying the puff numbers (20–480), nicotine contents (0–24 mg/mL), and collected e-cigarette samples through an impinger system for biological assays. The calculated samples' concentration ranged from 1.96 to 47.06 mg/mL. THP-1 monocyte-differentiated macrophages, BEAS-2B bronchial epithelial cells, wild-type C57BL/6 mice, and NF-κB-luc transgenic mice were used to test the effects of these samples. E-cigarette samples showed cytotoxicity to THP-1 cells and BEAS-2B in vitro, leading to increased oxidative stress, inflammatory cytokine production with or without nicotine, and cell death. Furthermore, aerosol generated from PG is more toxic than VG. The toxicity of e-cigarette samples is at least partially due to the reactive oxygen species and aldehydes, which are generated during the aerosolization processes by the e-cigarette device. After NF-κB-luc mice exposed with e-cigarette samples by oropharyngeal aspiration, NF-κB expressions were observed in a dose–response fashion with or without nicotine. In addition, the e-cigarette samples induced neutrophil infiltration, IL-1β production, oxidative stress marker heme oxygenase-1 expression in wild-type C57BL/6 mice. These results suggested that oxidative stress, pro-inflammatory NF-κB pathway activation, and cell death are involved in e-cigarette aerosol-induced acute lung inflammation. [ABSTRACT FROM AUTHOR]

Background. Portal vein tumor thrombosis (PVTT) is one of the major predictive factors for patients with hepatocellular carcinoma (HCC). The objective of this study was to establish a prognostic nomogram for identifying individual survival outcomes in patients with HCC and PVTT on conservative treatment based on specific factors. Methods. Two hundred and ten patients with HCC and PVTT on conservative treatment in Beijing Ditan Hospital between June 2008 and May 2017 were studied retrospectively as a derivation cohort. We built a nomogram based on independent risk factors for survival prediction. The concordance index (c-index) and a calibration curve were used to evaluate the predictive accuracy. During the study, 102 patients were included at the Putuo Hospital and Third People's Hospital of Changzhou as a validation cohort. Results. In the derivation cohort, the independent factors for overall survival were identified by multivariate analysis, namely, aspartate aminotransferase ≥119 IU/L, gamma-glutamyl transferase ≥115 IU/L, Child–Pugh class C liver function, creatinine ≥91 μmoI/L, α-fetoprotein ≥400 ng/ml, and largest tumor diameter ≥5 cm. The nomogram had a c-index of 0.737 (95% confidence interval, 0.692–0.782) and the calibration curves fitted well. The median survival time was 4.2 months in the derivation cohort, with an MST of 5 months for BCLC C stage and 1.8 months for BCLC D stage patients. Kaplan–Meier analysis showed significant statistical differences in the 6-month overall survival rates of the primary and validation cohorts after the total scores were divided into three quartiles (low risk: 0–85; intermediate risk: 86–210; high risk: ≥211; p < 0.0001 in both cohorts). Conclusions. The nomogram can be a more accurate and individualized prediction for 6-month overall survival of patients with HCC and PVTT on conservative treatment, and it is possible to consider further active interventions for patients in the low-risk group (0–85 scores) to achieve the aim of prolonging survival. [ABSTRACT FROM AUTHOR]

Neither the European standard nor the US standard for classification of intermediate class filters comprises testing of filter performance with respect to ultrafine particles (UFPs) or particles of the most penetrating size (MPPS). This could turn out to be a major lack in classification standards since UFPs have been pointed out as a serious health hazard. In this study, fractional efficiencies of eight new full-scale bag filters and twenty-three new filter medium samples were determined. The influence of air velocity and aerosol type was investigated, and correlations between efficiencies for UFPs (EFUFPs), MPPS-sized particles (EFMPPS) and 0.4 μm-sized particles (EF0.4μm) were established. The tested bag filters were challenged by four aerosol types: a neutralized atomized oil aerosol, the same oil aerosol but non-neutralized, a non-neutralized thermally generated oil smoke, and a “natural” indoor aerosol. The tests were carried out at different air velocities through the filter medium, ranging between 0.08 m/s and 0.22 m/s. The relationships that were observed between EFUFPs, EFMPPS,and EF0.4μmappeared to be linear within the observed filtration efficiency ranges. These relationships were similar regardless of the test aerosol type used, but somewhat different for glass fiber filters than for charged synthetic filters. Generally, EFMPPSwas 10–20% lower than EF0.4μm. The influence of air velocity variations on the size resolved efficiency was determined. The glass fiber filters showed practically the same fractional efficiencies regardless of whether the test aerosol was neutralized or not. However, the charged synthetic filters showed substantially lower efficiencies when tested with the non-neutralized aerosol compared to the case when the aerosol was neutralized. Copyright 2013 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

• Estimated bark beetle-caused tree mortality in the western US from aerial surveys. • A range of results from different methods indicates some uncertainty. • Annual Westwide tree mortality continued to be high in recent years. • Multiple severe outbreaks in different locations contributed to mortality. Bark beetle (Curculionidae, Scolytinae) outbreaks have been extensive and severe across the western United States in recent decades, and assessments of tree mortality are critical for documenting patterns and increasing understanding of drivers and impacts. Aerial surveys have produced a rich data set that includes damage severity, year and location of damage, and beetle and tree species. Here we update a data set of bark beetle-caused tree mortality for the western United States to include five additional years (now 1997–2018) and use these data to characterize recent outbreaks and compare with earlier tree mortality. We estimated "mortality area" (MA), the canopy area of beetle-killed trees and a more accurate representation of outbreak impacts than "affected area", as well as the number of killed trees. Recently, the US Forest Service changed survey approaches, creating challenges for linking observations from the old and new approaches. We compared four methods to harmonize these approaches to produce consistent time series of tree mortality. General similarity of MA occurred in several methods; however, the range of results indicated some uncertainty. Based on limited analyses and a desire to be conservative in damage estimates, we suggest that the FHP R1-R4 method, which produced intermediate mortality among the methods, is most realistic for representing tree mortality from bark beetles. Using this recommended method, we found that bark beetles caused 4.3 Mha of MA and 3.8x109 killed trees when summed across space, time, and bark beetle/host combination (range among methods: 1.5–7.4 Mha and 1.2–6.3 x 109 killed trees). This total mortality area was 4.7% of forest area in the western United States; 28% of this mortality occurred in 2013–2018. Annual tree mortality remained high recently, with values comparable to earlier years, and was a result of combinations of outbreaks of different beetle species in different regions with different timing. Bark beetles continue to be agents of significant forest disturbance in the western United States. Given a range of mortality area results from the different methods, we encourage further evaluation of estimates using independent observations. [ABSTRACT FROM AUTHOR]