Last data update: Jan 13, 2025. (Total: 48570 publications since 2009)
Records 1-30 (of 91 Records) |
Query Trace: Shaffer R[original query] |
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Heat inactivation of aqueous viable norovirus and MS2 bacteriophage
Shaffer M , Huynh K , Costantini V , Vinjé J , Bibby K . J Appl Microbiol 2024 AIMS: This study aimed to compare the heat inactivation kinetics of viable human norovirus with the surrogate, MS2 bacteriophage as well as assess the decay of the RNA signal. METHODS AND RESULTS: Human intestinal enteroids (HIEs) were used to analyze the heat inactivation kinetics of viable human norovirus compared to the surrogate MS2 bacteriophage, which was cultured using a plaque assay. Norovirus decay rates were 0.22 min-1, 0.68 min-1, and 1.11 min-1 for 50°C, 60°C, and 70°C, respectively, and MS2 bacteriophage decay rates were 0.0065 min-1, 0.045 min-1, and 0.16 min-1 for 50°C, 60°C, and 70°C, respectively. Norovirus had significantly higher decay rates than MS2 bacteriophage at all tested temperatures (P = 0.002-0.007). No decrease of RNA titers as measured by reverse transcription-PCR for both human norovirus and MS2 bacteriophage over time was observed, indicating molecular methods do not accurately depict viable human norovirus after heat inactivation and treatment efficiency is underestimated. CONCLUSIONS: Overall, our data demonstrates that MS2 bacteriophage is a conservative surrogate to measure heat inactivation and potentially overestimates the infectious risk of norovirus. Furthermore, this study corroborates that measuring viral RNA titers, as evaluated by PCR methods, does not correlate with the persistence of viable norovirus under heat inactivation. |
Viable norovirus persistence in water microcosms
Shaffer M , Huynh K , Costantini V , Bibby K , Vinjé J . Environ Sci Technol Lett 2022 9 (10) 851-855 Human noroviruses are one of the leading causes of acute gastroenteritis worldwide. Based on quantitative microbial risk assessments, norovirus contributes the greatest infectious risk of any pathogen from exposure to sewage-contaminated water; however, these estimates have been based upon molecular (i.e., RNA-based) data as human norovirus has remained largely unculturable in the laboratory. Current approaches to assess the environmental fate of noroviruses rely on the use of culturable surrogate viruses and molecular methods. Human intestinal enteroids (HIEs) are an emerging cell culture system capable of amplifying viable norovirus. Here, we applied the HIE assay to assess both viable norovirus and norovirus RNA persistence in surface, tap, and deionized water microcosms. Viable norovirus decreased to below the detection limit in tap and deionized water microcosms and was measured in a single replicate in the surface water microcosm at study conclusion (28 days). Conversely, the norovirus RNA signal remained constant over the duration of the study, even when viable norovirus was below the limit of detection. Our findings demonstrate the disconnect between current environmental norovirus detection via molecular methods and viability as assessed through the HIE assay. These results imply that molecular norovirus monitoring is not inherently representative of infectious norovirus. © 2022 American Chemical Society. |
Brief report: No differences between lopinavir/ritonavir and nonnucleoside reverse transcriptase inhibitor-based antiretroviral therapy on clearance of plasmodium falciparum subclinical parasitemia in adults living with HIV starting treatment (A5297)
Shaffer D , Kumwenda J , Chen H , Akelo V , Angira F , Kosgei J , Tonui R , Ssali F , McKhann A , Hogg E , Stewart VA , Murphy SC , Coombs R , Schooley R . J Acquir Immune Defic Syndr 2022 89 (2) 178-182 BACKGROUND: HIV protease inhibitors anti-Plasmodium falciparum activity in adults remains uncertain. METHODS: Adults with HIV CD4+ counts >200 cells/mm3 starting antiretroviral therapy (ART) with P. falciparum subclinical parasitemia (Pf SCP) were randomized 1:1 to (step 1) protease inhibitor lopinavir/ritonavir (LPV/r)-based (arm A) or nonnucleoside reverse transcriptase inhibitor (nNRTI)-based ART (arm B) for 15 days. In step 2, participants received nNRTI-based ART and trimethoprim/sulfamethoxazole prophylaxis for 15 days. P. falciparum SCP clearance was measured by polymerase chain reaction. The Fisher exact test [95% exact confidence interval (CI)] was used to compare proportions of P. falciparum SCP clearance (<10 parasites/L on 3 occasions within 24 hours) between LPV/r and nNRTI arms at day 15. The Kaplan-Meier method and log-rank test were used to compare time-to-clearance. RESULTS: Fifty-two adults from Kenya, Malawi, and Uganda with a median age = 31 (Q1, Q3: 24-39) years, 33% women, with baseline median CD4+ counts of 324 (259-404) cells/mm3, median HIV-1 RNA viremia of 5.18 log10 copies/mL (4.60-5.71), and median estimated P. falciparum density of 454 parasites/L (83-2219) enrolled in the study. Forty-nine (94%) participants completed the study. At day 15, there was no statistically significant difference in the proportions of P. falciparum SCP clearance between the LPV/r (23.1% clearance; 6 of the 26) and nNRTI (26.9% clearance; 7 of the 26) arms [between-arm difference 3.9% (95% CI, -21.1% to 28.4%; P = 1.00)]. No significant difference in time-to-clearance was observed between the arms (P = 0.80). CONCLUSIONS: In a small randomized study of adults starting ART with P. falciparum SCP, no statistically significant differences were seen between LPV/r- and nNRTI-based ART in P. falciparum SCP clearance after 15 days of treatment. |
Personal interventions for reducing exposure and risk for outdoor air pollution: An official American Thoracic Society Workshop report
Laumbach RJ , Cromar KR , Adamkiewicz G , Carlsten C , Charpin D , Chan WR , de Nazelle A , Forastiere F , Goldstein J , Gumy S , Hallman WK , Jerrett M , Kipen HM , Pirozzi CS , Polivka BJ , Radbel J , Shaffer RE , Sin DD , Viegi G . Ann Am Thorac Soc 2021 18 (9) 1435-1443 Poor air quality affects the health and wellbeing of large populations around the globe. Although source controls are the most effective approaches for improving air quality and reducing health risks, individuals can also take actions to reduce their personal exposure by staying indoors, reducing physical activity, altering modes of transportation, filtering indoor air, and using respirators and other types of face masks. A synthesis of available evidence on the efficacy, effectiveness, and potential adverse effects or unintended consequences of personal interventions for air pollution is needed by clinicians to assist patients and the public in making informed decisions about use of these interventions. To address this need, the American Thoracic Society convened a workshop in May of 2018 to bring together a multidisciplinary group of international experts to review the current state of knowledge about personal interventions for air pollution and important considerations when helping patients and the general public to make decisions about how best to protect themselves. From these discussions, recommendations were made regarding when, where, how, and for whom to consider personal interventions. In addition to the efficacy and safety of the various interventions, the committee considered evidence regarding the identification of patients at greatest risk, the reliability of air quality indices, the communication challenges, and the ethical and equity considerations that arise when discussing personal interventions to reduce exposure and risk from outdoor air pollution. |
Tracking cardiac rehabilitation participation and completion among Medicare beneficiaries to inform the efforts of a national initiative
Ritchey MD , Maresh S , McNeely J , Shaffer T , Jackson SL , Keteyian SJ , Brawner CA , Whooley MA , Chang T , Stolp H , Schieb L , Wright J . Circ Cardiovasc Qual Outcomes 2020 13 (1) e005902 BACKGROUND: Despite cardiac rehabilitation (CR) being shown to improve health outcomes among patients with heart disease, its use has been suboptimal. In response, the Million Hearts Cardiac Rehabilitation Collaborative developed a road map to improve CR use, including increasing participation rates to >/=70% by 2022. This observational study provides current estimates to measure progress and identifies the populations and regions most at risk for CR service underutilization. METHODS AND RESULTS: We identified Medicare fee-for-service beneficiaries who were CR eligible in 2016, and assessed CR participation (>/=1 CR session attended), timely initiation (participation within 21 days of event), and completion (>/=36 sessions attended) through 2017. Measures were assessed overall, by beneficiary characteristics and geography, and by primary CR-qualifying event type (acute myocardial infarction hospitalization; coronary artery bypass surgery; heart valve repair/replacement; percutaneous coronary intervention; or heart/heart-lung transplant). Among 366 103 CR-eligible beneficiaries, 89 327 (24.4%) participated in CR, of whom 24.3% initiated within 21 days and 26.9% completed CR. Eligibility was highest in the East South Central Census Division (14.8 per 1000). Participation decreased with increasing age, was lower among women (18.9%) compared with men (28.6%; adjusted prevalence ratio: 0.91 [95% CI, 0.90-0.93]) was lower among Hispanics (13.2%) and non-Hispanic blacks (13.6%) compared with non-Hispanic whites (25.8%; adjusted prevalence ratio: 0.63 [0.61-0.66] and 0.70 [0.67-0.72], respectively), and varied by hospital referral region and Census Division (range: 18.6% [East South Central] to 39.1% [West North Central]) and by qualifying event type (range: 7.1% [acute myocardial infarction without procedure] to 55.3% [coronary artery bypass surgery only]). Timely initiation varied by geography and qualifying event type; completion varied by geography. CONCLUSIONS: Only 1 in 4 CR-eligible Medicare beneficiaries participated in CR and marked disparities were observed. Reinforcement of current effective strategies and development of new strategies will be critical to address the noted disparities and achieve the 70% participation goal. |
Creating activity-friendly communities: Exploring the intersection of public health and the arts
Cornett K , Bray-Simons K , Devlin HM , Iyengar S , Moore Shaffer P , Fulton JE . J Phys Act Health 2019 16 (11) 1-3 Increasing physical activity in communities is a key public health strategy for chronic disease prevention and health promotion. Very few Americans get the minimum amount of physical activity necessary for substantial health benefits.1 Activity-friendly communities make physical activity easier or more accessible by providing opportunities for active transportation, leisure-time physical activity, or both.2 They are easy to navigate by foot, bicycle, or wheelchair, and they connect useful destinations, including public transit.3 |
Mouse pulmonary response to dust from sawing Corian(R), a solid-surface composite material
Mandler WK , Qi C , Orandle MS , Sarkisian K , Mercer RR , Stefaniak AB , Knepp AK , Bowers LN , Battelli LA , Shaffer J , Friend SA , Qian Y , Sisler JD . J Toxicol Environ Health A 2019 82 (11) 1-19 Corian(R), a solid-surface composite (SSC), is composed of alumina trihydrate and acrylic polymer. The aim of the present study was to examine the pulmonary toxicity attributed to exposure to SSC sawing dust. Male mice were exposed to either phosphate buffer saline (PBS, control), 62.5, 125, 250, 500, or 1000 microg of SSC dust, or 1000 microg silica (positive control) via oropharyngeal aspiration. Body weights were measured for the duration of the study. Bronchoalveolar lavage fluid (BALF) and tissues were collected for analysis at 1 and 14 days post-exposure. Enhanced-darkfield and histopathologic analysis was performed to assess particle distribution and inflammatory responses. BALF cells and inflammatory cytokines were measured. The geometric mean diameter of SSC sawing dust following suspension in PBS was 1.25 microm. BALF analysis indicated that lactate dehydrogenase (LDH) activity, inflammatory cells, and pro-inflammatory cytokines were significantly elevated in the 500 and 1000 microg SSC exposure groups at days 1 and 14, suggesting that exposure to these concentrations of SSC induced inflammatory responses, in some cases to a greater degree than the silica positive control. Histopathology indicated the presence of acute alveolitis at all doses at day 1, which was largely resolved by day 14. Alveolar particle deposition and granulomatous mass formation were observed in all exposure groups at day 14. The SSC particles were poorly cleared, with 81% remaining at the end of the observation period. These findings demonstrate that SSC sawing dust exposure induces pulmonary inflammation and damage that warrants further investigation. Abbreviations: ANOVA: Analysis of Variance; ATH: Alumina Trihydrate; BALF: Bronchoalveolar Lavage Fluid; Dpg: Geometric Mean Diameter; FE-SEM: Field Emission Scanning Electron Microscopy; IACUC: Institutional Animal Care and Use Committee; IFN-gamma: Interferon Gamma; IL-1 Beta: Interleukin-1 Beta; IL-10: Interleukin-10; IL-12: Interleukin-12; IL-2: Interleukin-2; IL-4: Interleukin-4; IL-5: Interleukin-5; IL-6: Interleukin-6; KC/GRO: Neutrophil-Activating Protein 3; MMAD: Mass Median Aerodynamic Diameter; PBS: Phosphate-Buffered Saline; PEL: Permissible Exposure Limit; PM: Polymorphonuclear Leukocytes; PNOR: Particles Not Otherwise Regulated; SEM/EDX: Scanning Electron Microscope/Energy-Dispersive X-Ray; SSA: Specific Surface Area; SSC: Solid Surface Composite; TNFalpha: Tumor Necrosis Factor-Alpha; VOC: Volatile Organic Compounds; sigmag: Geometric Standard Deviation. |
Toxicological assessment of dust from sanding micronized copper-treated lumber in vivo
Sisler JD , Mandler WK , Shaffer J , Lee T , McKinney WG , Battelli LA , Orandle MS , Thomas TA , Castranova VC , Qi C , Porter DW , Andrew ME , Fedan JS , Mercer RR , Qian Y . J Hazard Mater 2019 373 630-639 Micronized copper azole (MCA) is a lumber treatment improve longevity. In this study, the in vivo response to PM2.5 sanding dust generated from MCA-treated lumber was compared to that of untreated yellow pine (UYP) or soluble copper azole-treated (CA-C) lumber to determine if the MCA was more bioactive than CA-C. Mice were exposed to doses (28, 140, or 280 mug/mouse) of UYP, MCA, or CA-C sanding dust using oropharyngeal aspiration. Bronchoalveolar lavage fluid (BALF) lactate dehydrogenase activity was increased at 1 day post-exposure to 280 mug/mouse of MCA and CA-C compared to UYP. BALF polymorphonuclear cells were increased by MCA and CA-C. There were increases in BALF cytokines in MCA and CA-C-exposed groups at 1 day post-exposure. Lung histopathology indicated inflammation with infiltration of neutrophils and macrophages. Pulmonary responses were more severe in MCA and CA-C-exposed groups at 1 day post-exposure. MCA caused more severe inflammatory responses than CA-C at 1 day post-exposure. These findings suggest that the MCA and CA-C sanding dusts are more bioactive than the UYP sanding dust, and, moreover, the MCA sanding dust is more bioactive in comparison to the CA-C sanding dust. No chronic toxic effects were observed among all observed sanding dusts. |
A control banding framework for protecting the US workforce from aerosol transmissible infectious disease outbreaks with high public health consequences
Sietsema M , Radonovich L , Hearl FJ , Fisher EM , Brosseau LM , Shaffer RE , Koonin LM . Health Secur 2019 17 (2) 124-132 Recent high-profile infectious disease outbreaks illustrate the importance of selecting appropriate control measures to protect a wider range of employees, other than those in healthcare settings. In such settings, where routine exposure risks are often high, control measures may be more available, routinely implemented, and studied for effectiveness. In the absence of evidence-based guidelines or established best practices for selecting appropriate control measures, employers may unduly rely on personal protective equipment (PPE) because of its wide availability and pervasiveness as a control measure, circumventing other effective options for protection. Control banding is one approach that may be used to assign job tasks into risk categories and prioritize the application of controls. This article proposes an initial control banding framework for workers at all levels of risk and incorporates a range of control options, including PPE. Using the National Institutes of Health (NIH) risk groups as a surrogate for toxicity and combining the exposure duration with the exposure likelihood, we can generate the risk of a job task to the worker. |
Flammability of respirators and other head and facial personal protective equipment
Rengasamy S , Niezgoda G , Shaffer R . J Int Soc Respir Prot 2018 35 (1) 1-13 Background: Personal protective equipment (PPE) is worn by workers in surgical settings to protect them and patients. Food and Drug Administration (FDA) clears some PPE (e.g., surgical masks (SM)) as class II medical devices, and regulates some (e.g. surgical head cover) as class I exempt devices. For respiratory protection, National Institute for Occupational Safety and Health (NIOSH)-approved N95 filtering facepiece respirators (FFRs), and powered air-purifying respirators (PAPRs) are used. One type of PPE, "surgical N95 respirators", is a NIOSH-approved FFR that is also cleared by the FDA for use in medical settings. The surgical environment poses unique risks such as the potential for surgical fires. As part of its substantial equivalence determination process, FDA requests testing of flammability and other parameters for SM and surgical N95 respirators. A lack of data regarding flammability of PPE used in healthcare exists. We hypothesize that commonly used PPE, regardless of whether regulated and/or cleared by FDA or not, will pass an industry standard such as the 16 CFR 1610 flammability test. Methods: Eleven N95 FFR models, eight surgical N95 respirator models, seven SM models, five surgical head cover models, and five PAPR hood models were evaluated for flammability with a 45 degree flammability tester using the 16 CFR 1610 method. Three common fabrics were included for comparison. Results: All of the PPE samples regulated/and or cleared by FDA or not, passed the flammability test at class 1 (normal flammability), meaning they are less likely to burn. Only one of the three common fabrics, a cotton fabric at the lowest basis weight, was class 3 (high flammability). Conclusions: The results obtained in the study suggest that NIOSH-approved N95 FFRs would likely pass the 16 CFR 1610 flammability standard. Moreover, results suggest that NIOSH is capable of undertaking flammability testing using the 16 CFR 1610 standard as the flammability results NIOSH obtained for N95 FFRs were comparable to the results obtained by a third party independent laboratory. |
Healthcare personnel exposure in an emergency department during influenza season
Rule AM , Apau O , Ahrenholz SH , Brueck SE , Lindsley WG , de Perio MA , Noti JD , Shaffer RE , Rothman R , Grigorovitch A , Noorbakhsh B , Beezhold DH , Yorio PL , Perl TM , Fisher EM . PLoS One 2018 13 (8) e0203223 INTRODUCTION: Healthcare personnel are at high risk for exposure to influenza by direct and indirect contact, droplets and aerosols, and by aerosol generating procedures. Information on air and surface influenza contamination is needed to assist in developing guidance for proper prevention and control strategies. To understand the vulnerabilities of healthcare personnel, we measured influenza in the breathing zone of healthcare personnel, in air and on surfaces within a healthcare setting, and on filtering facepiece respirators worn by healthcare personnel when conducting patient care. METHODS: Thirty participants were recruited from an adult emergency department during the 2015 influenza season. Participants wore personal bioaerosol samplers for six hours of their work shift, submitted used filtering facepiece respirators and medical masks and completed questionnaires to assess frequency and types of interactions with potentially infected patients. Room air samples were collected using bioaerosol samplers, and surface swabs were collected from high-contact surfaces within the adult emergency department. Personal and room bioaerosol samples, surface swabs, and filtering facepiece respirators were analyzed for influenza A by polymerase chain reaction. RESULTS: Influenza was identified in 42% (53/125) of personal bioaerosol samples, 43% (28/ 96) of room bioaerosol samples, 76% (23/30) of pooled surface samples, and 25% (3/12) of the filtering facepiece respirators analyzed. Influenza copy numbers were greater in personal bioaerosol samples (17 to 631 copies) compared to room bioaerosol samples (16 to 323 copies). Regression analysis suggested that the amount of influenza in personal samples was approximately 2.3 times the amount in room samples (Wald chi2 = 16.21, p<0.001). CONCLUSIONS: Healthcare personnel may encounter increased concentrations of influenza virus when in close proximity to patients. Occupations that require contact with patients are at an increased risk for influenza exposure, which may occur throughout the influenza season. Filtering facepiece respirators may become contaminated with influenza when used during patient care. |
Assessment of environmental and surgical mask contamination at a student health center - 2012-2013 influenza season
Ahrenholz SH , Brueck SE , Rule AM , Noti JD , Noorbakhs B , Blachere FM , de Perio MA , Lindsley WG , Shaffer RE , Fisher EM . J Occup Environ Hyg 2018 15 (9) 1-30 Increased understanding of influenza transmission is critical for pandemic planning and selecting appropriate controls for healthcare personnel safety and health. The goals of this pilot study were to assess environmental contamination in different areas and at two time periods in the influenza season and to determine the feasibility of using surgical mask contamination to evaluate potential exposure to influenza virus. Bioaerosol samples were collected over 12 days (two 6-day sessions) at 12 locations within a student health center using portable two-stage bioaerosol samplers operating 8 hours each day. Surface samples were collected each morning and afternoon from common high-contact non-porous hard surfaces from rooms and locations where bioaerosol samplers were located. Surgical masks worn by participants while in contact with patients with influenza-like illness were collected. A questionnaire administered to each of the 12 participants at the end of each workday and another at the end of each workweek assessed influenza-like illness symptoms, estimated the number of influenza-like illness patient contacts, hand hygiene, and surgical mask usage. All samples were analyzed using qPCR. Over the 12 days of the study, three of the 127 (2.4%) bioaerosol samples, two of 483 (0.41%) surface samples, and zero of 54 surgical masks were positive for influenza virus. For the duration of contact that occurred with an influenza patient on any of the 12 days, nurse practitioners and physicians reported contacts with influenza-like illness patients > 60 minutes, medical assistants reported 15-44 minutes, and administrative staff reported < 30 minutes. Given the limited number of bioaerosol and surface samples positive for influenza virus in the bioaerosol and surface samples, the absence of influenza virus on the surgical masks provides inconclusive evidence for the potential to use surgical masks to assess exposure to influenza viruses. Further studies are needed to determine feasibility of this approach in assessing healthcare personnel exposures. Information learned in this study can inform future field studies on influenza transmission. |
Assessment of influenza virus exposure and recovery from contaminated surgical masks and N95 respirators
Blachere FM , Lindsley WG , McMillen CM , Beezhold DH , Fisher EM , Shaffer RE , Noti JD . J Virol Methods 2018 260 98-106 Healthcare workers (HCWs) are at significantly higher risk of exposure to influenza virus during seasonal epidemics and global pandemics. During the 2009 influenza pandemic, some healthcare organizations recommended that HCWs wear respiratory protection such as filtering facepiece respirators, while others indicated that facemasks such as surgical masks (SMs) were sufficient. To assess the level of exposure a HCW may possibly encounter, the aim of this study was to (1.) evaluate if SMs and N95 respirators can serve as "personal bioaerosol samplers" for influenza virus and (2.) determine if SMs and N95 respirators contaminated by influenza laden aerosols can serve as a source of infectious virus for indirect contact transmission. This effort is part of a National Institute for Occupational Safety and Health 5-year multidisciplinary study to determine the routes of influenza transmission in healthcare settings. A coughing simulator was programmed to cough aerosol particles containing influenza virus over a wide concentration range into an aerosol exposure simulation chamber virus/L of exam room air), and a breathing simulator was used to collect virus on either a SM or N95 respirator. Extraction buffers containing nonionic and anionic detergents as well as various protein additives were used to recover influenza virus from the masks and respirators. The inclusion of 0.1% SDS resulted in maximal influenza RNA recovery (41.3%) but with a complete loss of infectivity whereas inclusion of 0.1% bovine serum albumin resulted in reduced RNA recovery (6.8%) but maximal retention of virus infectivity (17.9%). Our results show that a HCW's potential exposure to airborne influenza virus can be assessed in part through analysis of their SMs and N95 respirators, which can effectively serve as personal bioaerosol samplers. |
A predictive 7-gene assay and prognostic protein biomarkers for non-small cell lung cancer
Guo NL , Dowlati A , Raese RA , Dong C , Chen G , Beer DG , Shaffer J , Singh S , Bokhary U , Liu L , Howington J , Hensing T , Qian Y . EBioMedicine 2018 32 102-110 PURPOSE: This study aims to develop a multi-gene assay predictive of the clinical benefits of chemotherapy in non-small cell lung cancer (NSCLC) patients, and substantiate their protein expression as potential therapeutic targets. PATIENTS AND METHODS: The mRNA expression of 160 genes identified from microarray was analyzed in qRT-PCR assays of independent 337 snap-frozen NSCLC tumors to develop a predictive signature. A clinical trial JBR.10 was included in the validation. Hazard ratio was used to select genes, and decision-trees were used to construct the predictive model. Protein expression was quantified with AQUA in 500 FFPE NSCLC samples. RESULTS: A 7-gene signature was identified from training cohort (n=83) with accurate patient stratification (P=0.0043) and was validated in independent patient cohorts (n=248, P<0.0001) in Kaplan-Meier analyses. In the predicted benefit group, there was a significantly better disease-specific survival in patients receiving adjuvant chemotherapy in both training (P=0.035) and validation (P=0.0049) sets. In the predicted non-benefit group, there was no survival benefit in patients receiving chemotherapy in either set. The protein expression of ZNF71 quantified with AQUA scores produced robust patient stratification in separate training (P=0.021) and validation (P=0.047) NSCLC cohorts. The protein expression of CD27 quantified with ELISA had a strong correlation with its mRNA expression in NSCLC tumors (Spearman coefficient=0.494, P<0.0088). Multiple signature genes had concordant DNA copy number variation, mRNA and protein expression in NSCLC progression. CONCLUSIONS: This study presents a predictive multi-gene assay and prognostic protein biomarkers clinically applicable for improving NSCLC treatment, with important implications in lung cancer chemotherapy and immunotherapy. |
Ebola Virus Persistence in Ocular Tissues and Fluids (EVICT) Study: reverse transcription-polymerase chain reaction and cataract surgery outcomes of Ebola survivors in Sierra Leone
Shantha JG , Mattia JG , Goba A , Barnes KG , Ebrahim FK , Kraft CS , Hayek BR , Hartnett JN , Shaffer JG , Schieffelin JS , Sandi JD , Momoh M , Jalloh S , Grant DS , Dierberg K , Chang J , Mishra S , Chan AK , Fowler R , O'Dempsey T , Kaluma E , Hendricks T , Reiners R , Reiners M , Gess LA , ONeill K , Kamara S , Wurie A , Mansaray M , Acharya NR , Liu WJ , Bavari S , Palacios G , Teshome M , Crozier I , Farmer PE , Uyeki TM , Bausch DG , Garry RF , Vandy MJ , Yeh S . EBioMedicine 2018 30 217-224 BACKGROUND: Ebola virus disease (EVD) survivors are at risk for uveitis during convalescence. Vision loss has been observed following uveitis due to cataracts. Since Ebola virus (EBOV) may persist in the ocular fluid of EVD survivors for an unknown duration, there are questions about the safety and feasibility of vision restorative cataract surgery in EVD survivors. METHODS: We conducted a cross-sectional study of EVD survivors anticipating cataract surgery and patients with active uveitis to evaluate EBOV RNA persistence in ocular fluid, as well as vision outcomes post cataract surgery. Patients with aqueous humor that tested negative for EBOV RNA were eligible to proceed with manual small incision cataract surgery (MSICS). FINDINGS: We screened 137 EVD survivors from June 2016 - August 2017 for enrolment. We enrolled 50 EVD survivors; 46 with visually significant cataract, 1 with a subluxated lens, 2 with active uveitis and 1 with a blind painful eye due to uveitis. The median age was 24.0years (IQR 17-35) and 35 patients (70%) were female. The median logMAR visual acuity (VA) was 3.0 (Snellen VA Hand motions; Interquartile Range, IQR: 1.2-3.0, Snellen VA 20/320 - Hand motions). All patients tested negative for EBOV RNA by RT-PCR in aqueous humor/vitreous fluid and conjunctiva at a median of 19months (IQR 18-20) from EVD diagnosis in Phase 1 of ocular fluid sampling and 34months (IQR 32-36) from EVD diagnosis in Phase 2 of ocular fluid sampling. Thirty-four patients underwent MSICS, with a preoperative median VA improvement from hand motions to 20/30 at three-month postoperative follow-up (P<0.001). INTERPRETATION: EBOV persistence by RT-PCR was not identified in ocular fluid or conjunctivae of fifty EVD survivors with ocular disease. Cataract surgery can be performed safely with vision restorative outcomes in patients who test negative for EBOV RNA in ocular fluid specimens. These findings impact the thousands of West African EVD survivors at-risk for ocular complications who may also require eye surgery during EVD convalescence. |
In vitro toxicological evaluation of surgical smoke from human tissue
Sisler JD , Shaffer J , Soo JC , LeBouf RF , Harper M , Qian Y , Lee T . J Occup Med Toxicol 2018 13 12 Background: Operating room personnel have the potential to be exposed to surgical smoke, the by-product of using electrocautery or laser surgical device, on a daily basis. Surgical smoke is made up of both biological by-products and chemical pollutants that have been shown to cause eye, skin and pulmonary irritation. Methods: In this study, surgical smoke was collected in real time in cell culture media by using an electrocautery surgical device to cut and coagulate human breast tissues. Airborne particle number concentration and particle distribution were determined by direct reading instruments. Airborne concentration of selected volatile organic compounds (VOCs) were determined by evacuated canisters. Head space analysis was conducted to quantify dissolved VOCs in cell culture medium. Human small airway epithelial cells (SAEC) and RAW 264.7 mouse macrophages (RAW) were exposed to surgical smoke in culture media for 24 h and then assayed for cell viability, lactate dehydrogenase (LDH) and superoxide production. Results: Our results demonstrated that surgical smoke-generated from human breast tissues induced cytotoxicity and LDH increases in both the SAEC and RAW. However, surgical smoke did not induce superoxide production in the SAEC or RAW. Conclusion: These data suggest that the surgical smoke is cytotoxic in vitro and support the previously published data that the surgical smoke may be an occupational hazard to healthcare workers. |
Physical chemical properties and cell toxicity of sanding copper-treated lumber
Sisler JD , Qi C , McKinney W , Shaffer J , Andrew M , Lee T , Thomas T , Castranova V , Mercer RR , Qian Y . J Occup Environ Hyg 2018 15 (4) 0 To protect against decay and fungal invasion into the wood, the micronized copper, copper carbonate particles, has been applied in the wood treatment in recent years; however, there is little information on the health risk associated with sanding micronized copper- treated lumber. In this study, wood dust from the sanding of micronized copper azole -treated lumber (MCA) was compared to sanding dust from solubilized copper azole-treated wood (CA-C) and untreated yellow pine (UYP). The test found that sanding MCA released a much higher concentration of nanoparticles than sanding CA-C and UYP, and the particles between about 0.4 microm to 2 microm from sanding MCA had the highest percentage of copper. The percentage of copper in the airborne dust from sanding CA-C had a weak dependency on particle size and was lower than that from sanding MCA. Nanoparticles were seen in the MCA PM2.5 particles, while none were detected in the UYP or CA-C. Inductively coupled plasma mass spectrometry (ICP-MS) analysis found that the bulk lumber for MCA and CA-C had relatively equal copper content; however, the PM2.5 particles from sanding the MCA had a higher copper concentration when compared to the PM2.5 particles from sanding UYP or CA-C. The cellular toxicity assays show that exposure of RAW 264.7 macrophages (RAW) to MCA and CA-C wood dust suspensions did not induce cellular toxicity even at the concentration of 200 microg PM2.5 wood dust/mL. Since the copper from the treated wood dust can leach into the wood dust supernatant, the supernatants of MCA, CA-C and UYP wood dusts were subjected to the cellular toxicity assays. The data showed that at the higher concentrations of copper (>/= 5 microg/ml), both MCA and CA-C supernatants induced cellular toxicity. This study suggests that sanding MCA-treated lumber releases copper nanoparticles and both the MCA and CA-C-treated lumber can release copper, which are potentially related to the observed in vitro toxicity. |
Project BREATHE - Prototype Respirator Evaluation Utilizing Newly Proposed Respirator Test Criteria
Kim JH , Roberge RJ , Shaffer RE , Zhuang Z , Powell JB , Bergman M , Palmiero AJ . J Int Soc Respir Prot 2017 34 (1) 1-9 Machine and human subject testing of four prototype filtering facepiece respirators (FFR) and two commercial FFR was carried out utilizing recently proposed respirator test criteria that address healthcare worker-identified comfort and tolerance issues. Overall, two FFR (one prototype, one commercial model) were able to pass all eight criteria and three FFR (two prototypes, one commercial model) were able to pass seven of eight criteria. One prototype FFR was not tested against the criteria due to an inability to obtain satisfactory results on human subject quantitative respirator fit testing. Future studies, testing different models and styles of FFR against the proposed criteria, will be required to gauge the overall utility and effectiveness of the criteria in determining FFR comfort and tolerance issues that may impact user compliance and, by extension, protection. |
Time to first positive HIV-1 DNA PCR may differ with antiretroviral regimen in infants infected with non-B subtype HIV-1.
Balasubramanian R , Fowler MG , Dominguez K , Lockman S , Tookey PA , Huong NNG , Nesheim S , Hughes MD , Lallemant M , Tosswill J , Shaffer N , Sherman G , Palumbo P , Shapiro DE . AIDS 2017 31 (18) 2465-2474 OBJECTIVE: To evaluate the association of type and timing of prophylactic maternal and infant antiretroviral regimen with time to first positive HIV-1 DNA PCR test, in nonbreastfed HIV-infected infants, from populations infected predominantly with HIV-1 non-B subtype virus. DESIGN: Analysis of combined data on nonbreastfed HIV-infected infants from prospective cohorts in Botswana, Thailand, and the United Kingdom (N = 405). METHODS: Parametric models appropriate for interval-censored outcomes estimated the time to first positive PCR according to maternal or infant antiretroviral regimen category and timing of maternal antiretroviral initiation, with adjustment for covariates. RESULTS: Maternal antiretroviral regimens included: no antiretrovirals (n = 138), single-nucleoside analog reverse transcriptase inhibitor (n = 165), single-dose nevirapine with zidovudine (n = 66), and combination prophylaxis with 3 or more antiretrovirals [combination antiretroviral therapy (cART), n = 36]. Type of maternal/infant antiretroviral regimen and timing of maternal antiretroviral initiation were each significantly associated with time to first positive PCR (multivariate P < 0.0001). The probability of a positive test with no antiretrovirals compared with the other regimen/timing groups was significantly lower at 1 day after birth, but did not differ significantly after age 14 days. In a subgroup of 143 infants testing negative at birth, infant cART was significantly associated with longer time to first positive test (multivariate P = 0.04). CONCLUSION: Time to first positive HIV-1 DNA PCR in HIV-1-infected nonbreastfed infants (non-B HIV subtype) may differ according to maternal/infant antiretroviral regimen and may be longer with infant cART, which may have implications for scheduling infant HIV PCR-diagnostic testing and confirming final infant HIV status. |
Assessment of reactive oxygen species generated by electronic cigarettes using acellular and cellular approaches
Zhao J , Zhang Y , Sisler JD , Shaffer J , Leonard SS , Morris AM , Qian Y , Bello D , Demokritou P . J Hazard Mater 2017 344 549-557 Electronic cigarettes (e-cigs) have fast increased in popularity but the physico-chemical properties and toxicity of the generated emission remain unclear. Reactive oxygen species (ROS) are likely present in e-cig emission and can play an important role in e-cig toxicity. However, e-cig ROS generation is poorly documented. Here, we generated e-cig exposures using a recently developed versatile exposure platform and performed systematic ROS characterization on e-cig emissions using complementary acellular and cellular techniques: 1) a novel acellular Trolox-based mass spectrometry method for total ROS and hydrogen peroxide (H2O2) detection, 2) electron spin resonance (ESR) for hydroxyl radical detection in an acellular and cellular systems and 3) in vitro ROS detection in small airway epithelial cells (SAEC) using the dihydroethidium (DHE) assay. Findings confirm ROS generation in cellular and acellular systems and is highly dependent on the e-cig brand, flavor, puffing pattern and voltage. Trolox method detected a total of 1.2-8.9nmol H2O2eq./puff; H2O2 accounted for 12-68% of total ROS. SAEC cells exposed to e-cig emissions generated up to eight times more ROS compared to control. The dependency of e-cig emission profile on e-cig features and operational parameters should be taken into consideration in toxicological studies. |
Pilot screening study of targeted genetic polymorphisms for association with seasonal influenza hospital admission.
Carter TC , Hebbring SJ , Liu J , Mosley JD , Shaffer CM , Ivacic LC , Kopitzke S , Stefanski EL , Strenn R , Sundaram ME , Meece J , Brilliant MH , Ferdinands JM , Belongia EA . J Med Virol 2017 90 (3) 436-446 Host response to influenza is highly variable, suggesting a potential role of host genetic variation. To investigate the host genetics of severe influenza in a targeted fashion, 32 single nucleotide polymorphisms (SNPs) within viral immune response genes were evaluated for association with seasonal influenza hospitalization in an adult study population with European ancestry. SNP allele and genotype frequencies were compared between hospitalized influenza patients (cases) and population controls in a case-control study that included a discovery group (26 cases and 993 controls) and two independent, validation groups (one with 84 cases and 4,076 controls; the other with 128 cases and 9,187 controls). Cases and controls had similar allele frequencies for variant rs12252 in interferon-inducible transmembrane protein 3 (IFITM3) (P > 0.05), and the study did not replicate the previously reported association of rs12252 with hospitalized influenza. In the discovery group, the preliminary finding of an association with a nonsense polymorphism (rs8072510) within the schlafen family member 13 (SFLN13) gene (P = 0.0099) was not confirmed in either validation group. Neither rs12252 nor rs8072510 showed an association according to the presence of clinical risk factors for influenza complications (P > 0.05), suggesting that these factors did not modify associations between the SNPs and hospitalized influenza. No other SNPs showed a statistically significant association with hospitalized influenza. Further research is needed to identify genetic factors involved in host response to seasonal influenza infection and to assess whether rs12252, a low-frequency variant in Europeans, contributes to influenza severity in populations with European ancestry. |
Transfer of bacteriophage MS2 and fluorescein from N95 filtering facepiece respirators to hands: Measuring fomite potential
Brady TM , Strauch AL , Almaguer CM , Niezgoda G , Shaffer RE , Yorio PL , Fisher EM . J Occup Environ Hyg 2017 14 (11) 0 Contact transmission of pathogens from personal protective equipment is a concern within the healthcare industry. During public health emergency outbreaks, resources become constrained and the reuse of personal protective equipment, such as N95 filtering facepiece respirators, may be needed. This study was designed to characterize the transfer of bacteriophage MS2 and fluorescein between filtering facepiece respirators and the wearer's hands during three simulated use scenarios. Filtering facepiece respirators were contaminated with MS2 and fluorescein in droplets or droplet nuclei. Thirteen test subjects performed filtering facepiece respirator use scenarios including improper doffing, proper doffing and reuse, and improper doffing and reuse. Fluorescein and MS2 contamination transfer were quantified. The average MS2 transfer from filtering facepiece respirators to the subjects' hands ranged from 7.6-15.4% and 2.2-2.7% for droplet and droplet nuclei derived contamination, respectively. Handling filtering facepiece respirators contaminated with droplets resulted in higher levels of MS2 transfer compared to droplet nuclei for all use scenarios (p = 0.007). MS2 transfer from droplet contaminated filtering facepiece respirators during improper doffing and reuse was greater than transfer during improper doffing (p = 0.008) and proper doffing and reuse (p = 0.042). Droplet contamination resulted in higher levels of fluorescein transfer compared to droplet nuclei contaminated filtering facepiece respirators for all use scenarios (p = 0.009). Fluorescein transfer was greater for improper doffing and reuse (p = 0.007) from droplet contaminated masks compared to droplet nuclei contaminated filtering facepiece respirators and for improper doffing and reuse when compared improper doffing (p = 0.017) and proper doffing and reuse (p = 0.018) for droplet contaminated filtering facepiece respirators. For droplet nuclei contaminated filtering facepiece respirators, the difference in MS2 and fluorescein transfer did not reach statistical significance when comparing any of the use scenarios. The findings suggest that the results of fluorescein and MS2 transfer were consistent and highly correlated across the conditions of study. The data supports CDC recommendations for using proper doffing techniques and discarding filtering facepiece respirators that are directly contaminated with secretions from a cough or sneeze. |
Physiological evaluation of cooling devices in conjunction with personal protective ensembles recommended for use in West Africa
Quinn T , Kim JH , Strauch A , Wu T , Powell J , Roberge R , Shaffer R , Coca A . Disaster Med Public Health Prep 2017 11 (5) 1-7 OBJECTIVE: Cooling devices (CDs) worn under personal protective equipment (PPE) can alleviate some of the heat stress faced by health care workers responding to the Ebola outbreak in West Africa. METHODS: Six healthy, young individuals were tested while wearing 4 different CDs or no cooling (control) under PPE in an environmental chamber (32 degrees C/92% relative humidity) while walking (3 METs, 2.5 mph, 0% grade) on a treadmill for 60 minutes. Exercise was preceded by a 15-minute stabilization period and a 15-minute donning period. RESULTS: The control condition resulted in a significantly higher rectal temperature (Tre) at the end of the exercise than did all CD conditions (CD1, P=0.004; CD2, P=0.01; CD3, P=0.000; CD4, P=0.000) with CD1 and CD2 resulting in a higher Tre than CD3 and CD4 (P<0.05). The control condition resulted in a higher heart rate (HR) at the end of exercise than did the CD3 (P=0.01) and CD4 (P=0.009) conditions, whereas the HR of the CD1 and CD2 conditions was higher than that of the CD3 and CD4 conditions (P<0.05). Weight loss in the control condition was higher than in the CD3 (P=0.003) and CD4 (P=0.01) conditions. Significant differences in subjective measurements of thermal stress were found across conditions and time. CONCLUSIONS: Use of CDs can be advantageous in decreasing the negative physiological and subjective responses to the heat stress encountered by health care workers wearing PPE in hot and humid environments. (Disaster Med Public Health Preparedness. 2017;page 1 of 7). |
Physiological evaluation of personal protective ensembles recommended for use in West Africa
Coca A , Quinn T , Kim JH , Wu T , Powell J , Roberge R , Shaffer R . Disaster Med Public Health Prep 2017 11 (5) 1-7 OBJECTIVE: Personal protective equipment (PPE) provides health care workers with a barrier to prevent human contact with viruses like Ebola and potential transmission of the disease. However, PPE can also introduce an additional physiological burden from potentially increased heat stress. This study evaluated the human physiological and subjective responses to continuous light exercise within environmental conditions similar to those in West Africa while wearing 3 different, commonly used PPE ensembles (E1, E2, and E3). METHODS: Six healthy individuals were tested in an environmental chamber (32 degrees C, 92% relative humidity) while walking (3 METs, 2.5 mph, 0% incline) on a treadmill for 60 minutes. All subjects wore medical scrubs and PPE items. E1 also had a face shield and fluid-resistant surgical gown; E2 additionally included goggles, coverall, and separate hood; and E3 also contained a highly impermeable coverall, separate hood, and surgical mask cover over the N95 respirator. RESULTS: Heart rate and core temperature at the end of the exercise were significantly higher for E2 and E3 than for E1. Subjective perceptions of heat and exertion were significantly higher for E2 and E3 than for E1. CONCLUSIONS: Heat stress and PPE training, as well as the implementation of a work-to-rest ratio that avoids dehydration and possible heat stress issues, are recommended. (Disaster Med Public Health Preparedness. 2017;page 1 of 7). |
Recommended test methods and pass/fail criteria for a respirator fit capability test of half-mask air-purifying respirators
Zhuang Z , Bergman M , Lei Z , Niezgoda G , Shaffer R . J Occup Environ Hyg 2017 14 (6) 473-481 This study assessed key test parameters and pass/fail criteria options for developing a respirator fit capability (RFC) test for half-mask air-purifying particulate respirators. Using a 25-subject test panel, benchmark RFC data were collected for 101 National Institute for Occupational Safety and Health-certified respirator models. These models were further grouped into 61 one-, two- or three-size families. Fit testing was done using a PortaCount Plus with N95-Companion accessory and an Occupational Safety and Health Administration-accepted quantitative fit test protocol. Three repeated tests (donnings) per subject/respirator model combination were performed. The panel passing rate (PPR) (number or percentage of the 25-subject panel achieving acceptable fit) was determined for each model using five different alternative criteria for determining acceptable fit.When the 101 models are evaluated individually (i.e., not grouped by families), the percentages of models capable of fitting > 75% (19/25 subjects) of the panel were 29% and 32% for subjects achieving a fit factor ≥ 100 for at least one of the first two donnings and at least one of three donnings, respectively. When the models are evaluated grouped into families and using > 75% of panel subjects achieving a fit factor ≥ 100 for at least one of two donnings as the PPR pass/fail criterion, 48% of all models can pass. When > 50% (13/25 subjects) of panel subjects was the PPR criterion, the percentage of passing models increased to 70%.Testing respirators grouped into families and evaluating the first two donnings for each of two respirator sizes provided the best balance between meeting end user expectations and creating a performance bar for manufacturers. Specifying the test criterion for a subject obtaining acceptable fit as achieving a fit factor ≥ 100 on at least one out of the two donnings is reasonable because a majority of existing respirator families can achieve an PPR of > 50% using this criterion. The different test criteria can be considered by standards development organizations when developing standards. |
Association of a postnatal parent education program for abusive head trauma with subsequent pediatric abusive head trauma hospitalization rates
Dias MS , Rottmund CM , Cappos KM , Reed ME , Wang M , Stetter C , Shaffer ML , Hollenbeak CS , Paul IM , Christian CW , Berger RP , Klevens J . JAMA Pediatr 2017 171 (3) 223-229 Importance: Studies suggest that a postnatal parental intervention may reduce the incidence of abusive head trauma (AHT) of infants and young children. Objective: To assess the effect of statewide universal AHT education for parents on AHT hospitalization rates in Pennsylvania and on parents' self-reported knowledge gains and parenting behaviors. Design, Setting, and Participants: Changes in AHT hospitalization rates in Pennsylvania before and during the intervention were compared with those in 5 other states lacking universal parental AHT education during the same period. Data were collected from maternity units and birthing centers throughout Pennsylvania from the parents of 1593834 infants born on these units from January 1, 2003, to December 31, 2013. Parental behavior and knowledge were assessed through immediate (n = 16111) and 7-month postintervention (n = 146) parent surveys in a per protocol analysis of evaluable parents. Interventions: Parents read a brochure, viewed an 8-minute video about infant crying and AHT, asked questions of the nurse, and signed a commitment statement affirming their participation. Educational posters were displayed on each unit. Main Outcomes and Measures: Changes in AHT hospitalization rates before and during the intervention in Pennsylvania and 5 other states. Secondary outcomes included self-reported knowledge gains and changes in parenting practices. Results: A total of 1180291 parents (74.1%) of children ranging in age from 0 to 23 months signed a commitment statement. Incidence rate ratios for hospitalization for AHT increased in Pennsylvania from 24.1 (95% CI, 22.1-26.3) to 26.6 (95% CI, 24.9-28.4) per 100000 children aged 0 to 23 months during the intervention period; changes in Pennsylvania were not significantly different from aggregate changes in the 5 other states, from 22.4 (95% CI, 21.2-23.6) to 22.0 (95% CI, 21.2-22.8) per 100000 children aged 0 to 23 months. A total of 16111 parents (21.5% men, 78.5% women) completed the postnatal survey. Despite an overall 74.1% adherence with the intervention, only 20.6% of parents saw the brochure and video and only 5.7% were exposed to the entire intervention. Among the respondents answering individual questions on the postnatal surveys, 10958 mothers (91.0%) and 2950 fathers (88.6%) reported learning a lot about understanding infant crying as normal; 11023 mothers (92.2%) and 2923 fathers (88.9%), calming their infant, 11396 mothers (94.6%) and 3035 fathers (91.9%), calming themselves; 10060 mothers (85.1%) and 2688 fathers (83.4%), selecting other infant caregivers; and 11435 mothers (94.8%) and 3201 fathers (95.8%), that the information would decrease the likelihood of shaking an infant. Among the 143 respondents completing the 7-month survey, 109 (76.2%) reported remembering the information while their child was crying. Conclusions and Relevance: This intervention was not associated with a reduction in pediatric AHT hospitalization rates but was associated with self-reported gains in parental knowledge that were retained for 7 months. |
A comparison of facemask and respirator filtration test methods
Rengasamy S , Shaffer R , Williams B , Smit S . J Occup Environ Hyg 2016 14 (2) 0 NIOSH published a Federal Register Notice to explore the possibility of incorporating FDA required filtration tests for surgical masks (SMs) in the 42 CFR Part 84 respirator certification process. There have been no published studies comparing the filtration efficiency test methods used for NIOSH certification of N95 filtering facepiece respirators (N95 FFRs) with those used by the FDA for clearance of SMs. To address this issue, filtration efficiencies of "N95 FFRs" including six N95 FFR models and three surgical N95 FFR models, and three SM models were measured using the NIOSH NaCl aerosol test method, and FDA required particulate filtration efficiency (PFE) and bacterial filtration efficiency (BFE) methods, and viral filtration efficiency (VFE) method. Five samples of each model were tested using each method. Both PFE and BFE tests were done using unneutralized particles as per FDA guidance document. PFE was measured using 0.1 microm size polystyrene latex particles and BFE with approximately 3.0 microm size particles containing Staphylococcus aureus bacteria. VFE was obtained using approximately 3.0 microm size particles containing phiX 174 as the challenge virus and Escherichia coli as the host. Results showed that the efficiencies measured by the NIOSH NaCl method for "N95 FFRs" were from 98.15 to 99.68% compared to 99.74 to 99.99% for PFE, 99.62 to 99.9% for BFE and 99.8 to 99.9% for VFE methods. Efficiencies by the NIOSH NaCl method were significantly (p = <0.05) lower than the other methods. SMs showed lower efficiencies (54.72 to 88.40%) than "N95 FFRs" measured by the NIOSH NaCl method, while PFE, BFE and VFE methods produced no significant difference. The above results show that the NIOSH NaCl method is relatively conservative and is able to identify poorly performing filtration devices. The higher efficiencies obtained using PFE, BFE and VFE methods show that adding these supplemental particle penetration methods will not improve respirator certification. |
Differential pulmonary effects of CoO and La2O3 metal oxide nanoparticle responses during aerosolized inhalation in mice
Sisler JD , Li R , McKinney W , Mercer RR , Ji Z , Xia T , Wang X , Shaffer J , Orandle M , Mihalchik AL , Battelli L , Chen BT , Wolfarth M , Andrew ME , Schwegler-Berry D , Porter DW , Castranova V , Nel A , Qian Y . Part Fibre Toxicol 2016 13 (1) 42 BACKGROUND: Although classified as metal oxides, cobalt monoxide (CoO) and lanthanum oxide (La2O3) nanoparticles, as representative transition and rare earth oxides, exhibit distinct material properties that may result in different hazardous potential in the lung. The current study was undertaken to compare the pulmonary effects of aerosolized whole body inhalation of these nanoparticles in mice. RESULTS: Mice were exposed to filtered air (control) and 10 or 30 mg/m(3) of each particle type for 4 days and then examined at 1 h, 1, 7 and 56 days post-exposure. The whole lung burden 1 h after the 4 day inhalation of CoO nanoparticles was 25 % of that for La2O3 nanoparticles. At 56 days post exposure, < 1 % of CoO nanoparticles remained in the lungs; however, 22-50 % of the La2O3 nanoparticles lung burden 1 h post exposure was retained at 56 days post exposure for low and high exposures. Significant accumulation of La2O3 nanoparticles in the tracheobronchial lymph nodes was noted at 56 days post exposure. When exposed to phagolysosomal simulated fluid, La nanoparticles formed urchin-shaped LaPO4 structures, suggesting that retention of this rare earth oxide nanoparticle may be due to complexation of cellular phosphates within lysosomes. CoO nanoparticles caused greater lactate dehydrogenase release in the bronchoalveolar fluid (BALF) compared to La2O3 nanoparticles at 1 day post exposure, while BAL cell differentials indicate that La2O3 nanoparticles generated more inflammatory cell infiltration at all doses and exposure points. Histopathological analysis showed acute inflammatory changes at 1 day after inhalation of either CoO or La2O3 nanoparticles. Only the 30 mg/m(3) La2O3 nanoparticles exposure caused chronic inflammatory changes and minimal fibrosis at day 56 post exposure. This is in agreement with activation of the NRLP3 inflammasome after in vitro exposure of differentiated THP-1 macrophages to La2O3 but not after CoO nanoparticles exposure. CONCLUSION: Taken together, the inhalation studies confirmed the trend of our previous sub-acute aspiration study, which reported that CoO nanoparticles induced more acute pulmonary toxicity, while La2O3 nanoparticles caused chronic inflammatory changes and minimal fibrosis. |
Prevalence of respiratory protective devices in U.S. health care facilities: implications for emergency preparedness
Wizner K , Stradtman L , Novak D , Shaffer R . Workplace Health Saf 2016 64 (8) 359-68 An online questionnaire was developed to explore respiratory protective device (RPD) prevalence in U.S. health care facilities. The survey was distributed to professional nursing society members in 2014 and again in 2015 receiving 322 and 232 participant responses, respectively. The purpose of this study was to explore if the emergency preparedness climate associated with Ebola virus disease changed the landscape of RPD use and awareness. Comparing response percentages from the two sampling time frames using bivariate analysis, no significant changes were found in types of RPDs used in health care settings. N95 filtering facepiece respirators continue to be the most prevalent RPD used in health care facilities, but powered air-purifying respirators are also popular, with regional use highest in the West and Midwest. Understanding RPD use prevalence could ensure that health care workers receive appropriate device trainings as well as improve supply matching for emergency RPD stockpiling. |
Speech intelligibility assessment of protective facemasks and air-purifying respirators
Palmiero AJ , Symons D , Morgan JW 3rd , Shaffer RE . J Occup Environ Hyg 2016 13 (12) 0 Speech Intelligibility (SI) is the perceived quality of sound transmission. In healthcare settings, the ability to communicate clearly with coworkers, patients, etc. is crucial to quality patient care and safety. The objectives of this study were to 1) assess the suitability of the Speech Transmission Index (STI) methods for testing reusable and disposable facial and respiratory personal protective equipment (protective facemasks [PF], N95 filtering facepiece respirators [N95 FFR], and elastomeric half-mask air-purifying respirators [EAPR]) commonly worn by healthcare workers, 2) quantify STI levels of these devices, and 3) contribute to the scientific body of knowledge in the area of SI. SI was assessed using the STI under two experimental conditions: 1) a modified version of the National Fire Protection Association 1981 Supplementary Voice Communications System Performance Test at a Signal to Noise Ratio (SNR) of -15 (66 dBA) and 2) STI measurements utilizing a range of modified pink noise levels (52.5 dBA (-2 SNR) -72.5 dBA (+7 SNR)) in 5.0 dBA increments. The PF models (Kimberly Clark 49214 and 3M 1818) had the least effect on SI interference, typically deviating from the STI baseline (no-mask condition) by 3% and 4% STI, respectively. The N95FFR (3M 1870, 3M 1860) had more effect on SI interference, typically differing from baseline by 13% and 17%, respectively for models tested. The EAPR models (Scott Xcel and North 5500) had the most significant impact on SI, differing from baseline by 42% for models tested. This data offers insight into the performance of these apparatus with respect to STI and may serve as a reference point for future respirator design considerations, standards development, testing and certification activities. |
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