C-reactive protein (CRP) and long-term air pollution with a focus on ultrafine particles

Background

Long-term exposure to ambient air pollution contributes to the global burden of disease by particularly affecting cardiovascular (CV) causes of death. We investigated the association between particle number concentration (PNC), a marker for ultrafine particles, and other air pollutants and high sensitivity C-reactive protein (hs-CRP) as a potential link between air pollution and CV disease.

Diesel engine exhaust exposure in underground mines: Comparison between different surrogates of particulate exposure

Exposure to diesel particulate matter (DPM) is frequently assessed by measuring indicators of carbon speciation, but these measurements may be affected by organic carbon (OC) interference. Furthermore, there are still questions regarding the reliability of direct-reading instruments (DRI) for measuring DPM, since these instruments are not specific and may be interfered by other aerosol sources. This study aimed to assess DPM exposure in 2 underground mines by filter-based methods and DRI and to assess the relationship between the measures of elemental carbon (EC) and the DRI to verify the association of these instruments to DPM. Filter-based methods of respirable combustible dust (RCD), EC, and total carbon (TC) were used to measure levels of personal and ambient DPM. For ambient measurements, DRI were used to monitor particle number concentration (PNC; PTrak), particle mass concentration (DustTrak DRX and DustTrak 8520), and the submicron fraction of EC (EC_1;Airtec). The association between ambient EC and the DRI was assessed by Spearman correlation. Geometric mean concentrations of RCD, respirable TC (TC_R) and respirable elemental EC (EC_R) were 170 µg/m³, 148 µg/m³, and 83 µg/m³ for personal samples, and 197 µg/m³, 151 µg/m³, and 100 µg/m³ for ambient samples. Personal measurements had higher TC_R:EC_R ratios compared to ambient samples (1.8 vs. 1.50) and weaker association between EC_R and TC_R. Among the DRI, the measures of EC₁ by the Airtec (ρ = 0.86; P < 0.001) and the respirable particles by the DustTrak 8520 (ρ = 0.74; P < 0.001) showed the strongest association with EC, while PNC showed a weak and non-significant association with EC. In conclusion, this study provided important information about the concentrations of DPM in underground mines by measuring several indicators using filter-based methods and DRI. Among the DRI, the Airtec proved to be a good tool for estimating EC concentrations and, although the DustTrak showed good association with EC, interferences from other aerosol sources should be considered when using this instrument to assess DPM.     

An indoor air quality evaluation in a residential retrofit project using spray polyurethane foam

Understanding of indoor air quality (IAQ) during and after spray polyurethane foam (SPF) application is essential to protect the health of both workers and building occupants. Previous efforts such as field monitoring, micro-chamber/spray booth emission studies, and fate/transport modeling have been conducted to understand the chemical exposure of SPF and guide risk mitigation strategies. However, each type of research has its limitation and can only reveal partial information on the relationship between SPF and IAQ. A comprehensive study is truly needed to integrate the experimental design and analytical testing methods in the field/chamber studies with the mathematical tools employed in the modeling studies. This study aims to bridge this gap and provide a more comprehensive understanding on the impact of SPF to IAQ. The field sampling plan of this research aims to evaluate the airborne concentrations of methylene diphenyl diisocyanate (MDI), formaldehyde, acetaldehyde, propionaldehyde, tris(1-chlor-2-propyl)phosphate (TCPP), trans-1-chloro-3,3,3-trifluoropropene (Solstice^TM), and airborne particles. Modifications to existing MDI sampling and analytical methods were made so that level of quantification was improved. In addition, key fate and transport modeling input parameters such as air changes per hour and airborne particle size distribution were measured. More importantly, TCPP accumulation onto materials was evaluated, which is important to study the fate and transport of semi-volatile organic compounds. The IAQ results showed that after spray application was completed in the entire building, airborne concentrations decreased for all chemicals monitored. However, it is our recommendation that during SPF application, no one should return to the application site without proper personal protection equipment as long as there are active spray activities in the building. The comparison between this field study and a recent chamber study proved surface sorption and particle deposition is an important factor in determining the fate of airborne TCPP. The study also suggests the need for further evaluation by employing mathematical models, proving the data generated in this work as informative to industry and the broader scientific community.     

In-Room Ultraviolet Air Filtration Units Reduce Airborne Particles During Total Joint Arthroplasty

Reducing airborne bioburden in total joint arthroplasty (TJA) is of critical importance. The efficacy of crystalline ultraviolet-C (C-UVC) filtration in reducing bioburden in a dynamic operating room (OR) environment has not been evaluated. We assessed whether C-UVC filtration reduced (i) total particle counts (TPC); (ii) viable particle counts (VPC); and (iii) colony-forming units (CFUs). Fifty primary TJA cases were performed in a positive-pressure OR; 25 cases with the C-UVC unit and 25 cases without. The air was sampled by a particle counter and an impact air sampler to measure particle counts and CFUs, respectively. To compare TPC, VPC, and CFU/m³ between groups, independent t tests and multivariate regression, adjusted for number of OR staff and door openings, were performed. The C-UVC group had significantly lower TPC (2.6 × 10⁶ vs. 4.7 × 10⁶ particles, p = 0.001) and VPC (18,605 vs. 27,516 particles, p = 0.001). There were fewer CFUs in the C-UVC group (10.9 CFU/m³ vs. 13.7 CFU/m³, p = 0.163). Multivariate analysis identified C-UVC filtration as a significant predictor of decreased TPC (β = −0.44, p = 0.002) and VPC (β = −0.47, p = 0.001) after accounting for door openings and number of OR staff. The reduction in CFUs was not significant on multivariate analysis. In this prospective pilot study, a C-UVC air disinfection and recirculation unit led to a significant reduction in both TPC and VPC and a non-significant reduction in CFU. Statement of clinical significance: Further studies are needed to investigate the effects of C-UVC filtration units on surgical-site infection rates. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:431-437, 2020     

常州地区医院制剂室空气中尘粒和细菌总数的检测

在检测的常州地区１４所医院制剂室的超净工作台与洁净间空气中，细菌总数未超标者仅有１所，空气中尘粒数均未超标者亦仅７所。为此，应加强对制剂室防止空气污染的管理与监测。     

Impact of Diesel Exhaust Particles on Th2 Response in the Lung in Asthmatic Mice

Although it has been accepted that pulmonary exposure to diesel exhaust particles (DEP), representative constituents in particulate matter of mass median aerodynamic diameter < or 2.5 µm (PM_2.5), exacerbates murine allergic asthma, the in vivo effects of DEP on their cellular events in the context of allergen-specific Th response have never been examined. The aim of this study is to elucidate whether in vivo repetitive exposure to DEP combined with allergen (ovalbumin) facilitate allergen-specific Th response in the lung using a simple ex vivo assay system. As a result, repetitive pulmonary exposure to DEP in vivo, if combined with allergen, amplifies ex vivo allergen-specific Th2 response in the lung compared to that to allergen alone, characterized by high levels of interleukin (IL)-4 and IL-5. The result suggests that in asthmatic subjects, DEP promote Th2-prone milieu in the lung, which additively/synergistically augment asthma pathophysiology in vivo.     

稳心颗粒与普罗帕酮治疗早搏的疗效观察

目的观察稳心颗粒与普罗帕酮治疗早搏的疗效。方法选择我院收治的早搏患者100例,平均分为治疗组与对照组,对照组采用普罗帕酮治疗,治疗组采取稳心颗粒治疗,比较两组疗效。结果治疗组的总有效率高于对照组(P<0.05)。结论早搏疾病选用稳心颗粒治疗效果显著,值得推广应用。     

龙牡壮骨颗粒对小鼠性激素水平的影响

摘 要 目的:探讨龙牡壮骨颗粒对性激素水平的影响。方法: 昆明小鼠雌雄各30只,以该制剂溶于水制成溶液剂为供试药,以双蒸水为空白对照。受试小鼠按性别随机分为龙牡壮骨颗粒雌性高、等效剂量组和龙牡壮骨颗粒雄性高、等效剂量组,给药14 d,观察对血清睾酮、雌二醇含量和骨指标的影响。结果:龙牡壮骨颗粒能显著提高小鼠骨干重、骨密度、骨量,等效剂量龙牡壮骨颗粒组还能明显提高雄性小鼠骨湿重（P=0.022）,等效剂量龙牡壮骨颗粒对小鼠性激素水平无影响（P=0.855）。高剂量龙牡壮骨颗粒显著降低雄性小鼠雌二醇水平（P=0.048）。结论: 与临床剂量等效的龙牡壮骨颗粒对小鼠骨质有增强作用,同时对小鼠性激素水平无影响。     

HPLC法同时测定菊兰感冒颗粒中绿原酸、黄芩苷和木犀草素的含量

目的：建立同时测定菊兰感冒颗粒中绿原酸、黄芩苷和木犀草素等3种成分的HPLC方法。方法：采用Diamosil C18（2）色谱柱（250 mm×4.6 mm,5μm）;乙腈-0.2%磷酸溶液为流动相,流速为1.0 ml·min^-1,梯度洗脱;柱温35℃;检测波长为327 nm（绿原酸和黄芩苷）、360 nm（木犀草素）。结果：绿原酸、黄芩苷和木犀草素的线性范围分别为0.50-9.96μg·ml-1（r=0.999 8）、10.10-202.00μg·ml^-1（r=0.999 5）、0.10-2.04μg·ml^-1（r=0.999 6）;平均回收率分别为98.13%、98.80%、99.62%;RSD分别为0.65%、0.26%、0.57%（n=6）。结论：该法简便、稳定、重复性好,可用于菊兰感冒颗粒中绿原酸、黄芩苷和木犀草素的含量测定。     

Accumulation of lipids and oxidatively damaged DNA in hepatocytes exposed to particles

Exposure to particles has been suggested to generate hepatosteatosis by oxidative stress mechanisms. We investigated lipid accumulation in cultured human hepatocytes (HepG2) and rat liver after exposure to four different carbon-based particles. HepG2 cells were exposed to particles for 3 h and subsequently incubated for another 18 h to manifest lipid accumulation. In an animal model of metabolic syndrome we investigated the association between intake of carbon black (CB, 14 nm) particles and hepatic lipid accumulation, inflammation and gene expression of Srebp-1, Fasn and Scd-1 involved in lipid synthesis. There was a concentration-dependent increase in intracellular lipid content after exposure to CB in HepG2 cells, which was only observed after co-exposure to oleic/palmitic acid. Similar results were observed in HepG2 cells after exposure to diesel exhaust particles, fullerenes C₆₀ or pristine single-walled carbon nanotubes. All four types of particles also generated oxidatively damaged DNA, assessed as formamidopyrimidine DNA glycosylase (FPG) sensitive sites, in HepG2 cells after 3 h exposure. The animal model of metabolic syndrome showed increased lipid load in the liver after one oral exposure to 6.4 mg/kg of CB in lean Zucker rats. This was not associated with increased iNOS staining in the liver, indicating that the oral CB exposure was associated with hepatic steatosis rather than steatohepatitis. The lipid accumulation did not seem to be related to increased lipogenesis because there were unaltered gene expression levels in both the HepG2 cells and rat livers. Collectively, exposure to particles is associated with oxidative stress and steatosis in hepatocytes.