Last data update: Dec 02, 2024. (Total: 48272 publications since 2009)
Records 1-30 (of 57 Records) |
Query Trace: Birch R[original query] |
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Pollen and asthma morbidity in Atlanta: A 26-year time-series study
Lappe BL , Ebelt S , D'Souza RR , Manangan A , Brown C , Saha S , Harris D , Chang HH , Sole A , Scovronick N . Environ Int 2023 177 107998 BACKGROUND: Compared to many environmental risk factors, the relationship between pollen and asthma is understudied, including how associations may differ by pollen type and between subgroups, and how associations may be changing over time. OBJECTIVES: We evaluated the association between ambient pollen concentrations and emergency department (ED) visits for asthma and wheeze in Atlanta, Georgia during 1993-2018. We estimated overall associations for 13 individual pollen taxa, as well as associations by decade, race, age (5-17, 18-64, 65+), and insurance status (Medicaid vs non-Medicaid). METHODS: Speciated pollen data were acquired from Atlanta Allergy & Asthma, a nationally certified pollen counting station. ED visit data were obtained from individual hospitals and from the Georgia Hospital Association. We performed time-series analyses using quasi-Poisson distributed lag models, with primary analyses assessing 3-day (lag 0-2 days) pollen levels. Models controlled for day of week, holidays, air temperature, month, year, and month-by-year interactions. RESULTS: From 1993 to 2018, there were 686,259 ED visits for asthma and wheeze in the dataset, and the number of ED visits increased over time. We observed positive associations of asthma and wheeze ED visits with nine of the 13 pollen taxa: trees (maple, birch, pine, oak, willow, sycamore, and mulberry), two weeds (nettle and pigweed), and grasses. Rate ratios indicated 1-8% increases in asthma and wheeze ED visits per standard deviation increases in pollen. In general, we observed stronger associations in the earliest period (1993-2000), in younger people, and in Black patients; however, results varied by pollen taxa. CONCLUSIONS: Some, but not all, types of pollen are associated with increased ED visits for asthma/wheeze. Associations are generally higher in Black and younger patients and appear to have decreased over time. |
Patient and epidemiological factors associated with influenza testing in hospitalized adults with acute respiratory illnesses, 2016-2017 to 2019-2020
Dalton AF , Couture A , DeSilva MB , Irving SA , Gohil S , Rao S , Fink RV , Naleway AL , Guo Z , Sundaresan D , Birch RJ , Ball S , Zheng K , Ong TC , Reed C , Bozio CH . Open Forum Infect Dis 2023 10 (4) ofad162 BACKGROUND: Data are limited on influenza testing among adults with acute respiratory illness (ARI)-associated hospitalizations. We identified factors associated with influenza testing in adult ARI-associated hospitalizations across the 2016-2017 through 2019-2020 influenza seasons. METHODS: Using data from 4 health systems in the United States, we identified hospitalizations that had an ARI discharge diagnosis or respiratory virus test. A hospitalization with influenza testing was based on testing performed within 14 days before through 72 hours after admission. We used random forest analysis to identify patient characteristics and influenza activity indicators that were most important in terms of their relationship to influenza testing. RESULTS: Across 4 seasons, testing rates ranged from 14.8%-19.4% at 3 pooled sites and 60.1%-78.5% at a fourth site with different testing practices. Discharge diagnoses of pneumonia or infectious disease of noninfluenza etiology, presence of ARI signs/symptoms, hospital admission month, and influenza-like illness activity level were consistently among the variables with the greatest relative importance. CONCLUSIONS: Select ARI diagnoses and indicators of influenza activity were the most important factors associated with influenza testing among ARI-associated hospitalizations. Improved understanding of which patients are tested may enhance influenza burden estimates and allow for more timely clinical management of influenza-associated hospitalizations. |
Correlation between graphitic carbon and elemental carbon in diesel particulate matter in workplace atmospheres
Zheng L , Birch ME , Johnson B , Breitenstein M , Snawder J , Kulkarni P . Anal Chem 2023 95 (6) 3283-3290 We investigated the suitability of the graphitic carbon (GC) content of diesel particulate matter (DPM), measured using Raman spectroscopy, as a surrogate measure of elemental carbon (EC) determined by thermal optical analysis. The Raman spectra in the range of 800-1800 cm(-1) (including the D mode at ∼1322 cm(-1) and the G mode at ∼1595 cm(-1)) were used for GC identification and quantification. Comparison of the Raman spectra for two certified DPM standards (NIST SRM 1650 and SRM 2975), two types of diesel engine exhaust soot, and three types of DPM-enriched workplace aerosols show that the uncertainty of GC quantification based on the D peak height, G peak height, and the total peak area below D and G peaks was about 6.0, 6.7, and 6.9%, respectively. The low uncertainty for different aerosol types suggested possible use of GC as a surrogate measure of EC in workplace atmospheres. A calibration curve was constructed using two laboratory-aerosolized DPM standards to describe the relationship between GC measured by a portable Raman spectrometer and the EC concentration determined by NIOSH Method 5040. The calibration curve was then applied to determine GC-based estimates of the EC contents of diesel engine exhaust samples from two vehicles and seven air samples collected at a hydraulic fracturing worksite. The GC-EC estimates obtained through Raman measurements agreed well with those found by NIOSH Method 5040 for the same samples at EC filter loadings below 2.86 μg/cm(2). The study shows that using an appropriate sample collection method that avoids high filter mass loadings, onsite measurement of GC by a portable or hand-held Raman spectrometer can provide a useful indicator of EC in workplace aerosol. |
In vitro activity of the novel antifungal olorofim against Scedosporium And Lomentospora prolificans
Georgacopoulos O , Nunnally N , Law D , Birch M , Berkow EL , Lockhart SR . Microbiol Spectr 2023 11 (1) e0278922 Scedosporium spp. and Lomentospora prolificans are an emerging group of fungi refractory to current antifungal treatments. These species largely affect immunocompromised individuals but can also be lung colonizers in cystic fibrosis patients. Although Scedosporium apiospermum is thought to be the predominant species, the group has been expanded to a species complex. The distribution of species within the S. apiospermum species complex and other closely related species in the United States is largely unknown. Here, we used β-tubulin and ITS sequences to identify 37 Scedosporium isolates to the species level. These Scedosporium isolates as well as 13 L. prolificans isolates were tested against a panel of nine antifungal drugs, including the first in novel class orotimide, olorofim. IMPORTANCE Scedosporium and Lomentospora infections are notoriously hard to treat as these organisms can be resistant to numerous antifungals. The manuscript contributes to our knowledge of the activity of the new antifungal agent olorofim and comparator agents against Lomentospora and against Scedosporium isolates that have been molecularly identified to the species level. The efficacy of olorofim against all species of Scedosporium and Lomentospora was confirmed. |
Waning of vaccine effectiveness against moderate and severe covid-19 among adults in the US from the VISION network: test negative, case-control study.
Ferdinands JM , Rao S , Dixon BE , Mitchell PK , DeSilva MB , Irving SA , Lewis N , Natarajan K , Stenehjem E , Grannis SJ , Han J , McEvoy C , Ong TC , Naleway AL , Reese SE , Embi PJ , Dascomb K , Klein NP , Griggs EP , Liao IC , Yang DH , Fadel WF , Grisel N , Goddard K , Patel P , Murthy K , Birch R , Valvi NR , Arndorfer J , Zerbo O , Dickerson M , Raiyani C , Williams J , Bozio CH , Blanton L , Link-Gelles R , Barron MA , Gaglani M , Thompson MG , Fireman B . BMJ 2022 379 e072141 OBJECTIVE: To estimate the effectiveness of mRNA vaccines against moderate and severe covid-19 in adults by time since second, third, or fourth doses, and by age and immunocompromised status. DESIGN: Test negative case-control study. SETTING: Hospitals, emergency departments, and urgent care clinics in 10 US states, 17 January 2021 to 12 July 2022. PARTICIPANTS: 893 461 adults (≥18 years) admitted to one of 261 hospitals or to one of 272 emergency department or 119 urgent care centers for covid-like illness tested for SARS-CoV-2. MAIN OUTCOME MEASURES: The main outcome was waning of vaccine effectiveness with BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) vaccine during the omicron and delta periods, and the period before delta was dominant using logistic regression conditioned on calendar week and geographic area while adjusting for age, race, ethnicity, local virus circulation, immunocompromised status, and likelihood of being vaccinated. RESULTS: 45 903 people admitted to hospital with covid-19 (cases) were compared with 213 103 people with covid-like illness who tested negative for SARS-CoV-2 (controls), and 103 287 people admitted to emergency department or urgent care with covid-19 (cases) were compared with 531 168 people with covid-like illness who tested negative for SARS-CoV-2. In the omicron period, vaccine effectiveness against covid-19 requiring admission to hospital was 89% (95% confidence interval 88% to 90%) within two months after dose 3 but waned to 66% (63% to 68%) by four to five months. Vaccine effectiveness of three doses against emergency department or urgent care visits was 83% (82% to 84%) initially but waned to 46% (44% to 49%) by four to five months. Waning was evident in all subgroups, including young adults and individuals who were not immunocompromised; although waning was morein people who were immunocompromised. Vaccine effectiveness increased among most groups after a fourth dose in whom this booster was recommended. CONCLUSIONS: Effectiveness of mRNA vaccines against moderate and severe covid-19 waned with time after vaccination. The findings support recommendations for a booster dose after a primary series and consideration of additional booster doses. |
Use and impact of type 2 diabetes prevention interventions
Campione JR , Ritchie ND , Fishbein HA , Mardon RE , Johnson MCJr , Pace W , Birch RJ , Seeholzer EL , Zhang X , Proia K , Siegel KR , McKeever Bullard K . Am J Prev Med 2022 63 (4) 603-610 INTRODUCTION: RCTs have found that type 2 diabetes can be prevented among high-risk individuals by metformin medication and evidence-based lifestyle change programs. The purpose of this study is to estimate the use of interventions to prevent type 2 diabetes in real-world clinical practice settings and determine the impact on diabetes-related clinical outcomes. METHODS: The analysis performed in 2020 used 2010‒2018 electronic health record data from 69,434 patients aged ≥18 years at high risk for type 2 diabetes in 2 health systems. The use and impact of prescribed metformin, lifestyle change program, bariatric surgery, and combinations of the 3 were examined. A subanalysis was performed to examine uptake and retention among patients referred to the National Diabetes Prevention Program. RESULTS: Mean HbA1c values declined from before to after intervention for patients who were prescribed metformin (-0.067%; p<0.001) or had bariatric surgery (-0.318%; p<0.001). Among patients referred to the National Diabetes Prevention Program lifestyle change program, the type 2 diabetes postintervention incidence proportion was 14.0% for nonattendees, 12.8% for some attendance, and 7.5% for those who attended ≥4 sessions (p<0.001). Among referred patients to the National Diabetes Prevention Program lifestyle change program, uptake was low (13% for 1‒3 sessions, 15% for ≥4 sessions), especially among males and Hispanic patients. CONCLUSIONS: Findings suggest that metformin and bariatric surgery may improve HbA1c levels and that participation in the National Diabetes Prevention Program may reduce type 2 diabetes incidence. Efforts to increase the use of these interventions may have positive impacts on diabetes-related health outcomes. |
Waning 2-Dose and 3-Dose Effectiveness of mRNA Vaccines Against COVID-19-Associated Emergency Department and Urgent Care Encounters and Hospitalizations Among Adults During Periods of Delta and Omicron Variant Predominance - VISION Network, 10 States, August 2021-January 2022.
Ferdinands JM , Rao S , Dixon BE , Mitchell PK , DeSilva MB , Irving SA , Lewis N , Natarajan K , Stenehjem E , Grannis SJ , Han J , McEvoy C , Ong TC , Naleway AL , Reese SE , Embi PJ , Dascomb K , Klein NP , Griggs EP , Konatham D , Kharbanda AB , Yang DH , Fadel WF , Grisel N , Goddard K , Patel P , Liao IC , Birch R , Valvi NR , Reynolds S , Arndorfer J , Zerbo O , Dickerson M , Murthy K , Williams J , Bozio CH , Blanton L , Verani JR , Schrag SJ , Dalton AF , Wondimu MH , Link-Gelles R , Azziz-Baumgartner E , Barron MA , Gaglani M , Thompson MG , Fireman B . MMWR Morb Mortal Wkly Rep 2022 71 (7) 255-263 CDC recommends that all persons aged ≥12 years receive a booster dose of COVID-19 mRNA vaccine ≥5 months after completion of a primary mRNA vaccination series and that immunocompromised persons receive a third primary dose.* Waning of vaccine protection after 2 doses of mRNA vaccine has been observed during the period of the SARS-CoV-2 B.1.617.2 (Delta) variant predominance(†) (1-5), but little is known about durability of protection after 3 doses during periods of Delta or SARS-CoV-2 B.1.1.529 (Omicron) variant predominance. A test-negative case-control study design using data from eight VISION Network sites(§) examined vaccine effectiveness (VE) against COVID-19 emergency department/urgent care (ED/UC) visits and hospitalizations among U.S. adults aged ≥18 years at various time points after receipt of a second or third vaccine dose during two periods: Delta variant predominance and Omicron variant predominance (i.e., periods when each variant accounted for ≥50% of sequenced isolates).(¶) Persons categorized as having received 3 doses included those who received a third dose in a primary series or a booster dose after a 2 dose primary series (including the reduced-dosage Moderna booster). The VISION Network analyzed 241,204 ED/UC encounters** and 93,408 hospitalizations across 10 states during August 26, 2021-January 22, 2022. VE after receipt of both 2 and 3 doses was lower during the Omicron-predominant than during the Delta-predominant period at all time points evaluated. During both periods, VE after receipt of a third dose was higher than that after a second dose; however, VE waned with increasing time since vaccination. During the Omicron period, VE against ED/UC visits was 87% during the first 2 months after a third dose and decreased to 66% among those vaccinated 4-5 months earlier; VE against hospitalizations was 91% during the first 2 months following a third dose and decreased to 78% ≥4 months after a third dose. For both Delta- and Omicron-predominant periods, VE was generally higher for protection against hospitalizations than against ED/UC visits. All eligible persons should remain up to date with recommended COVID-19 vaccinations to best protect against COVID-19-associated hospitalizations and ED/UC visits. |
Nano-enhanced treatment of per-fluorinated and poly-fluorinated alkyl substances (PFAS)
Birch QT , Birch ME , Nadagouda MN , Dionysiou DD . Curr Opin Chem Eng 2022 35 Per-fluorinated and poly-fluorinated alkyl substances (PFAS) are environmentally pervasive and persistent. They have been associated with adverse health effects and are a major public health concern. Water contamination is a highly challenging problem due to the large number of PFAS and the limitations of conventional treatments. Nanoscale technologies offer new approaches such as high-capacity, selective sorbents with rapid uptake and regeneration, and integrated methods that capture and destroy PFAS. Nano-enhanced materials can improve the kinetics and selectivity of PFAS uptake (physical removal) and destruction, and the treatment materials can potentially be reused/recycled. Nanoscale technologies also offer opportunities to improve the performance of most conventional treatments. Some recent nano-enhanced approaches for PFAS treatment of aqueous media are discussed in this paper. © 2021 Elsevier B.V. |
Coronavirus Disease Contact Tracing Outcomes and Cost, Salt Lake County, Utah, USA, March-May 2020.
Fields VL , Kracalik IT , Carthel C , Lopez A , Schwartz A , Lewis NM , Bray M , Claflin C , Jorgensen K , Khong H , Richards W , Risk I , Smithee M , Clawson M , Booth LC , Scribellito T , Lowry J , Huynh J , Davis L , Birch H , Tran T , Walker J , Fry A , Hall A , Baker J , Pevzner E , Dunn AC , Tate JE , Kirking HL , Kiphibane T , Tran CH . Emerg Infect Dis 2021 27 (12) 2999-3008 Outcomes and costs of coronavirus disease (COVID-19) contact tracing are limited. During March-May 2020, we constructed transmission chains from 184 index cases and 1,499 contacts in Salt Lake County, Utah, USA, to assess outcomes and estimate staff time and salaries. We estimated 1,102 staff hours and $29,234 spent investigating index cases and contacts. Among contacts, 374 (25%) had COVID-19; secondary case detection rate was ≈31% among first-generation contacts, ≈16% among second- and third-generation contacts, and ≈12% among fourth-, fifth-, and sixth-generation contacts. At initial interview, 51% (187/370) of contacts were COVID-19-positive; 35% (98/277) became positive during 14-day quarantine. Median time from symptom onset to investigation was 7 days for index cases and 4 days for first-generation contacts. Contact tracing reduced the number of cases between contact generations and time between symptom onset and investigation but required substantial resources. Our findings can help jurisdictions allocate resources for contact tracing. |
Laboratory-Confirmed COVID-19 Among Adults Hospitalized with COVID-19-Like Illness with Infection-Induced or mRNA Vaccine-Induced SARS-CoV-2 Immunity - Nine States, January-September 2021.
Bozio CH , Grannis SJ , Naleway AL , Ong TC , Butterfield KA , DeSilva MB , Natarajan K , Yang DH , Rao S , Klein NP , Irving SA , Dixon BE , Dascomb K , Liao IC , Reynolds S , McEvoy C , Han J , Reese SE , Lewis N , Fadel WF , Grisel N , Murthy K , Ferdinands J , Kharbanda AB , Mitchell PK , Goddard K , Embi PJ , Arndorfer J , Raiyani C , Patel P , Rowley EA , Fireman B , Valvi NR , Griggs EP , Levy ME , Zerbo O , Porter RM , Birch RJ , Blanton L , Ball SW , Steffens A , Olson N , Williams J , Dickerson M , McMorrow M , Schrag SJ , Verani JR , Fry AM , Azziz-Baumgartner E , Barron M , Gaglani M , Thompson MG , Stenehjem E . MMWR Morb Mortal Wkly Rep 2021 70 (44) 1539-1544 Previous infection with SARS-CoV-2 (the virus that causes COVID-19) or COVID-19 vaccination can provide immunity and protection from subsequent SARS-CoV-2 infection and illness. CDC used data from the VISION Network* to examine hospitalizations in adults with COVID-19-like illness and compared the odds of receiving a positive SARS-CoV-2 test result, and thus having laboratory-confirmed COVID-19, between unvaccinated patients with a previous SARS-CoV-2 infection occurring 90-179 days before COVID-19-like illness hospitalization, and patients who were fully vaccinated with an mRNA COVID-19 vaccine 90-179 days before hospitalization with no previous documented SARS-CoV-2 infection. Hospitalized adults aged ≥18 years with COVID-19-like illness were included if they had received testing at least twice: once associated with a COVID-19-like illness hospitalization during January-September 2021 and at least once earlier (since February 1, 2020, and ≥14 days before that hospitalization). Among COVID-19-like illness hospitalizations in persons whose previous infection or vaccination occurred 90-179 days earlier, the odds of laboratory-confirmed COVID-19 (adjusted for sociodemographic and health characteristics) among unvaccinated, previously infected adults were higher than the odds among fully vaccinated recipients of an mRNA COVID-19 vaccine with no previous documented infection (adjusted odds ratio [aOR] = 5.49; 95% confidence interval [CI] = 2.75-10.99). These findings suggest that among hospitalized adults with COVID-19-like illness whose previous infection or vaccination occurred 90-179 days earlier, vaccine-induced immunity was more protective than infection-induced immunity against laboratory-confirmed COVID-19. All eligible persons should be vaccinated against COVID-19 as soon as possible, including unvaccinated persons previously infected with SARS-CoV-2. |
The "Outcome Reporting in Brief Intervention Trials: Alcohol" (ORBITAL) core outcome set: International consensus on outcomes to measure in efficacy and effectiveness trials of alcohol brief interventions
Shorter GW , Bray JW , Heather N , Berman AH , Giles EL , Clarke M , Barbosa C , O'Donnell AJ , Holloway A , Riper H , Daeppen JB , Monteiro MG , Saitz R , McNeely J , McKnight-Eily L , Cowell A , Toner P , Newbury-Birch D . J Stud Alcohol Drugs 2021 82 (5) 638-646 OBJECTIVE: The purpose of this study was to report the "Outcome Reporting in Brief Intervention Trials: Alcohol" (ORBITAL) recommended core outcome set (COS) to improve efficacy and effectiveness trials/evaluations for alcohol brief interventions (ABIs). METHOD: A systematic review identified 2,641 outcomes in 401 ABI articles measured by 1,560 different approaches. These outcomes were classified into outcome categories, and 150 participants from 19 countries participated in a two-round e-Delphi outcome prioritization exercise. This process prioritized 15 of 93 outcome categories for discussion at a consensus meeting of key stakeholders to decide the COS. A psychometric evaluation determined how to measure the outcomes. RESULTS: Ten outcomes were voted into the COS at the consensus meeting: (a) typical frequency, (b) typical quantity, (c) frequency of heavy episodic drinking, (d) combined consumption measure summarizing alcohol use, (e) hazardous or harmful drinking (average consumption), (f) standard drinks consumed in the past week (recent, current consumption), (g) alcohol-related consequences, (h) alcohol-related injury, (i) use of emergency health care services (impact of alcohol use), and (j) quality of life. CONCLUSIONS: The ORBITAL COS is an international consensus standard for future ABI trials and evaluations. It can improve the synthesis of new findings, reduce redundant/selective reporting (i.e., reporting only some, usually significant outcomes), improve between-study comparisons, and enhance the relevance of trial and evaluation findings to decision makers. The COS is the recommended minimum and does not exclude other, additional outcomes. |
Effectiveness of Covid-19 Vaccines in Ambulatory and Inpatient Care Settings.
Thompson MG , Stenehjem E , Grannis S , Ball SW , Naleway AL , Ong TC , DeSilva MB , Natarajan K , Bozio CH , Lewis N , Dascomb K , Dixon BE , Birch RJ , Irving SA , Rao S , Kharbanda E , Han J , Reynolds S , Goddard K , Grisel N , Fadel WF , Levy ME , Ferdinands J , Fireman B , Arndorfer J , Valvi NR , Rowley EA , Patel P , Zerbo O , Griggs EP , Porter RM , Demarco M , Blanton L , Steffens A , Zhuang Y , Olson N , Barron M , Shifflett P , Schrag SJ , Verani JR , Fry A , Gaglani M , Azziz-Baumgartner E , Klein NP . N Engl J Med 2021 385 (15) 1355-1371 BACKGROUND: There are limited data on the effectiveness of the vaccines against symptomatic coronavirus disease 2019 (Covid-19) currently authorized in the United States with respect to hospitalization, admission to an intensive care unit (ICU), or ambulatory care in an emergency department or urgent care clinic. METHODS: We conducted a study involving adults (≥50 years of age) with Covid-19-like illness who underwent molecular testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We assessed 41,552 admissions to 187 hospitals and 21,522 visits to 221 emergency departments or urgent care clinics during the period from January 1 through June 22, 2021, in multiple states. The patients' vaccination status was documented in electronic health records and immunization registries. We used a test-negative design to estimate vaccine effectiveness by comparing the odds of a positive test for SARS-CoV-2 infection among vaccinated patients with those among unvaccinated patients. Vaccine effectiveness was adjusted with weights based on propensity-for-vaccination scores and according to age, geographic region, calendar time (days from January 1, 2021, to the index date for each medical visit), and local virus circulation. RESULTS: The effectiveness of full messenger RNA (mRNA) vaccination (≥14 days after the second dose) was 89% (95% confidence interval [CI], 87 to 91) against laboratory-confirmed SARS-CoV-2 infection leading to hospitalization, 90% (95% CI, 85 to 93) against infection leading to an ICU admission, and 91% (95% CI, 89 to 93) against infection leading to an emergency department or urgent care clinic visit. The effectiveness of full vaccination with respect to a Covid-19-associated hospitalization or emergency department or urgent care clinic visit was similar with the BNT162b2 and mRNA-1273 vaccines and ranged from 81% to 95% among adults 85 years of age or older, persons with chronic medical conditions, and Black or Hispanic adults. The effectiveness of the Ad26.COV2.S vaccine was 68% (95% CI, 50 to 79) against laboratory-confirmed SARS-CoV-2 infection leading to hospitalization and 73% (95% CI, 59 to 82) against infection leading to an emergency department or urgent care clinic visit. CONCLUSIONS: Covid-19 vaccines in the United States were highly effective against SARS-CoV-2 infection requiring hospitalization, ICU admission, or an emergency department or urgent care clinic visit. This vaccine effectiveness extended to populations that are disproportionately affected by SARS-CoV-2 infection. (Funded by the Centers for Disease Control and Prevention.). |
In Vitro Activity of Novel Antifungal Olorofim against Filamentous Fungi and Comparison to Eight Other Antifungal Agents
Georgacopoulos O , Nunnally NS , Ransom EM , Law D , Birch M , Lockhart SR , Berkow EL . J Fungi (Basel) 2021 7 (5) Olorofim is a novel antifungal drug that belongs to the orotomide drug class which inhibits fungal dihydroorotate dehydrogenase (DHODH), thus halting pyrimidine biosynthesis and ultimately DNA synthesis, cell growth and division. It is being developed at a time when many invasive fungal infections exhibit antifungal resistance or have limited treatment options. The goal of this study was to evaluate the in vitro effectiveness of olorofim against a large collection of recently isolated, clinically relevant American mold isolates. In vitro antifungal activity was determined for 246 azole-susceptible Aspergillus fumigatus isolates, five A. fumigatus with TR(34)/L98H-mediated resistance, 19 Rhizopus species isolates, 21 Fusarium species isolates, and one isolate each of six other species of molds. Olorofim minimum inhibitory concentrations (MICs) were compared to antifungal susceptibility testing profiles for amphotericin B, anidulafungin, caspofungin, isavuconazole, itraconazole, micafungin, posaconazole, and voriconazole. Olorofim MICs were significantly lower than those of the echinocandin and azole drug classes and amphotericin B. A. fumigatus wild type and resistant isolates shared the same MIC50 = 0.008 μg/mL. In non-Aspergillus susceptible isolates (MIC ≤ 2 μg/mL), the geometric mean (GM) MIC to olorofim was 0.54 μg/mL with a range of 0.015-2 μg/mL. Olorofim had no antifungal activity (MIC ≥ 2 μg/mL) against 10% of the collection (31 in 297), including some isolates from Rhizopus spp. and Fusarium spp. Olorofim showed promising activity against A. fumigatus and other molds regardless of acquired azole resistance. |
Surface contamination generated by "one-pot" methamphetamine production
Ciesielski AL , Wagner JR , Alexander-Scott M , Smith J , Snawder J . J Chem Health Saf 2021 28 (1) 49-54 Methamphetamine production is the most common form of illicit drug manufacture in the United States. The "one-pot"method is the most prevalent methamphetamine synthesis method and is a modified Birch reduction, reducing pseudoephedrine with lithium and ammonia gas generated in situ. This research examined the amount of methamphetamine surface contamination generated by one-pot syntheses or "cooks", as well as the effectiveness of hosing with water as a simplified decontamination technique, to assess associated public health and environmental consequences. Concentrations of methamphetamine contamination were examined prior to production, after production, and after decontamination with water. Contamination was qualitatively field screened using lateral flow immunoassays and quantitatively assessed using a fluorescence covalent microbead immunosorbent assay. Following screening, 0 of 23 pre-cook samples, 29 of 41 post-cook samples, and 5 of 27 post-decontamination samples were positive. Quantitatively, one pre-cook sample had a methamphetamine concentration of 1.36 ng/100 cm2. Post-cook and post-decontamination samples had average methamphetamine concentrations of 26.50 ± 63.83 and 6.22 ± 12.17 ng/100 cm2, respectively. While all one-pot methamphetamine laboratories generate different amounts of waste, depending on the amount of precursors used and whether the reaction vessel remained uncompromised, this study examined the surface contamination generated by a popular one-pot method known to law enforcement. By understanding the amount of surface contamination generated by common methods of one-pot methamphetamine production and the effectiveness of decontamination techniques used to remediate them, health risks associated with these production sites can be better understood and environmental contamination can be mitigated. |
Physicochemical characterization and genotoxicity of the broad class of carbon nanotubes and nanofibers used or produced in U.S. facilities.
Fraser K , Kodali V , Yanamala N , Birch ME , Cena L , Casuccio G , Bunker K , Lersch TL , Evans DE , Stefaniak A , Hammer MA , Kashon ML , Boots T , Eye T , Hubczak J , Friend SA , Dahm M , Schubauer-Berigan MK , Siegrist K , Lowry D , Bauer AK , Sargent LM , Erdely A . Part Fibre Toxicol 2020 17 (1) 62 BACKGROUND: Carbon nanotubes and nanofibers (CNT/F) have known toxicity but simultaneous comparative studies of the broad material class, especially those with a larger diameter, with computational analyses linking toxicity to their fundamental material characteristics was lacking. It was unclear if all CNT/F confer similar toxicity, in particular, genotoxicity. Nine CNT/F (MW #1-7 and CNF #1-2), commonly found in exposure assessment studies of U.S. facilities, were evaluated with reported diameters ranging from 6 to 150 nm. All materials were extensively characterized to include distributions of physical dimensions and prevalence of bundled agglomerates. Human bronchial epithelial cells were exposed to the nine CNT/F (0-24 μg/ml) to determine cell viability, inflammation, cellular oxidative stress, micronuclei formation, and DNA double-strand breakage. Computational modeling was used to understand various permutations of physicochemical characteristics and toxicity outcomes. RESULTS: Analyses of the CNT/F physicochemical characteristics illustrate that using detailed distributions of physical dimensions provided a more consistent grouping of CNT/F compared to using particle dimension means alone. In fact, analysis of binning of nominal tube physical dimensions alone produced a similar grouping as all characterization parameters together. All materials induced epithelial cell toxicity and micronuclei formation within the dose range tested. Cellular oxidative stress, DNA double strand breaks, and micronuclei formation consistently clustered together and with larger physical CNT/F dimensions and agglomerate characteristics but were distinct from inflammatory protein changes. Larger nominal tube diameters, greater lengths, and bundled agglomerate characteristics were associated with greater severity of effect. The portion of tubes with greater nominal length and larger diameters within a sample was not the majority in number, meaning a smaller percentage of tubes with these characteristics was sufficient to increase toxicity. Many of the traditional physicochemical characteristics including surface area, density, impurities, and dustiness did not cluster with the toxicity outcomes. CONCLUSION: Distributions of physical dimensions provided more consistent grouping of CNT/F with respect to toxicity outcomes compared to means only. All CNT/F induced some level of genotoxicity in human epithelial cells. The severity of toxicity was dependent on the sample containing a proportion of tubes with greater nominal lengths and diameters. |
The Longitudinal Epidemiologic Assessment of Diabetes Risk (LEADR): Unique 1.4 M patient Electronic Health Record cohort.
Fishbein HA , Birch RJ , Mathew SM , Sawyer HL , Pulver G , Poling J , Kaelber D , Mardon R , Johnson MC , Pace W , Umbel KD , Zhang X , Siegel KR , Imperatore G , Shrestha S , Proia K , Cheng Y , McKeever Bullard K , Gregg EW , Rolka D , Pavkov ME . Healthc (Amst) 2020 8 (4) 100458 BACKGROUND: The Longitudinal Epidemiologic Assessment of Diabetes Risk (LEADR) study uses a novel Electronic Health Record (EHR) data approach as a tool to assess the epidemiology of known and new risk factors for type 2 diabetes mellitus (T2DM) and study how prevention interventions affect progression to and onset of T2DM. We created an electronic cohort of 1.4 million patients having had at least 4 encounters with a healthcare organization for at least 24-months; were aged ≥18 years in 2010; and had no diabetes (i.e., T1DM or T2DM) at cohort entry or in the 12 months following entry. EHR data came from patients at nine healthcare organizations across the U.S. between January 1, 2010-December 31, 2016. RESULTS: Approximately 5.9% of the LEADR cohort (82,922 patients) developed T2DM, providing opportunities to explore longitudinal clinical care, medication use, risk factor trajectories, and diagnoses for these patients, compared with patients similarly matched prior to disease onset. CONCLUSIONS: LEADR represents one of the largest EHR databases to have repurposed EHR data to examine patients' T2DM risk. This paper is first in a series demonstrating this novel approach to studying T2DM. IMPLICATIONS: Chronic conditions that often take years to develop can be studied efficiently using EHR data in a retrospective design. LEVEL OF EVIDENCE: While much is already known about T2DM risk, this EHR's cohort's 160 M data points for 1.4 M people over six years, provides opportunities to investigate new unique risk factors and evaluate research hypotheses where results could modify public health practice for preventing T2DM. |
Highly sensitive lab on a chip (LOC) immunoassay for early diagnosis of respiratory disease caused by respirable crystalline silica (RCS)
Upaassana VT , Ghosh S , Chakraborty A , Birch ME , Joseph P , Han J , Ku BK , Ahn CH . Anal Chem 2019 91 (10) 6652-6660 Respirable crystalline silica (RCS) produced in mining and construction industries can cause life-threatening diseases such as silicosis, lung cancer, and chronic obstructive pulmonary disease (COPD). These diseases could be more effectively treated and prevented if RCS-related biomarkers were identified and measured at an early stage of disease progression, which makes development of a point of care test (POCT) platform extremely desirable for early diagnosis. In this work, a new, highly sensitive lab on a chip (LOC) immunoassay has been designed, developed, and characterized for tumor necrosis factor alpha (TNF-alpha), a protein biomarker that causes lung inflammation due to RCS exposure. The designed LOC device is composed of four reservoirs for sample, enzyme conjugated detection antibody, wash buffer, and chemiluminescence substrate in liquid form, along with three spiral reaction chambers for test, positive control, and negative control. All reservoirs and spiral microchannels were connected in series and designed to perform sequential delivery of immunoassay reagents with minimal user intervention. The developed LOC measured TNF-alpha concentrations as low as 16 pg/mL in plasma from RCS-exposed rats and also had a limit of detection (LOD) of 0.5 pg/mL in spiked artificial serum. In addition, the analysis time was drastically reduced to about 30 min, as opposed to hours in conventional methods. Successful implementation of a highly sensitive, chemiluminescence-based immunoassay on a preloaded LOC with proper quality control, as reported in this work, can pave the way toward developing a new rapid POCT platform for in-field clinical diagnosis. |
Eliminating neglected tropical diseases in urban areas: A review of challenges, strategies and research directions for successful mass drug administration
Adams AM , Vuckovic M , Birch E , Brant TA , Bialek S , Yoon D , Koroma J , Direny A , Shott J , Lemoine JF , Dembele M , Baker MC . Trop Med Infect Dis 2018 3 (4) Since 1950, the global urban population grew from 746 million to almost 4 billion and is expected to reach 6.4 billion by mid-century. Almost 90% of this increase will take place in Asia and Africa and disproportionately in urban slums. In this context, concerns about the amplification of several neglected tropical diseases (NTDs) are warranted and efforts towards achieving effective mass drug administration (MDA) coverage become even more important. This narrative review considers the published literature on MDA implementation for specific NTDs and in-country experiences under the ENVISION and END in Africa projects to surface features of urban settings that challenge delivery strategies known to work in rural areas. Discussed under the thematics of governance, population heterogeneity, mobility and community trust in MDA, these features include weak public health infrastructure and programs, challenges related to engaging diverse and dynamic populations and the limited accessibility of certain urban settings such as slums. Although the core components of MDA programs for NTDs in urban settings are similar to those in rural areas, their delivery may need adjustment. Effective coverage of MDA in diverse urban populations can be supported by tailored approaches informed by mapping studies, research that identifies context-specific methods to increase MDA coverage and rigorous monitoring and evaluation. |
Aerosolization and characterization of carbon nanotube and nanofiber materials: Relationship between aerosol properties and bulk density
Ku BK , Birch ME . J Aerosol Sci 2019 127 38-48 Potential inhalation of fibrous carbon nanomaterials depends on the manufacturing/handling process and their tendency for air dispersion. Because of the large variety of carbon nanotube and nanofiber (CNT and CNF) products, with varying physical and chemical properties, characterization of these materials and their associated exposure risks is challenging. In this study, we aerosolized different types of CNT and CNF materials using an acoustic generator (AG) and characterized their aerodynamic and physical properties. The generation characteristics of the AG for the different CNT and CNF materials were investigated by measuring aerosol number concentrations and its decay properties with time. Airborne particle properties such as mobility and aerodynamic diameters were measured using mobility and aerodynamic particle sizers. The bulk and effective densities of the powder and aerosol were obtained by measuring the mass and volume of the bulk material and aerosol particles, where effective density was calculated by a tandem mobility-mass technique. The relationship between the aerosol properties (i.e., particle size, concentration, and dustiness) and bulk density of the material was also investigated to understand the potential for dispersion in air. The results showed that the aerosol concentration decay for each nanomaterial has a unique time constant, and that the rate of decay is positively correlated with the bulk density of the powder: the lower the bulk density, the slower the concentration decay. The aerodynamic diameter increased with increasing bulk density, while the mobility diameter showed the opposite trend. In general, bulk density is smaller than the particle effective density, and the effective density tends to approach the bulk density as particle size increases. Also, the bulk density of the fibrous nanomaterials tested in this study showed a reasonable correlation with dustiness data obtained from both our measurements and the literature, which was relatively weak for non-fibrous powders. This study indicates that more loosely agglomerated CNT powders, with lower bulk densities, would be more readily dispersed, and the dispersed particles remain airborne for longer periods. Depending on particle size, such materials can pose higher exposure risks due to their ease of dispersion and longer residence times. |
3-dimensional printing with nano-enabled filaments releases polymer particles containing carbon nanotubes into air
Stefaniak AB , Bowers LN , Knepp AK , Virji MA , Birch EM , Ham JE , Wells JR , Qi C , Schwegler-Berry D , Friend S , Johnson AR , Martin SBJr , Qian Y , LeBouf RF , Birch Q , Hammond D . Indoor Air 2018 28 (6) 840-851 Fused deposition modeling (FDM() ) 3-dimensional printing uses polymer filament to build objects. Some polymer filaments are formulated with additives, though it is unknown if they are released during printing. Three commercially-available filaments that contained carbon nanotubes (CNTs) were printed with a desktop FDM() 3-D printer in a chamber while monitoring total particle number concentration and size distribution. Airborne particles were collected on filters and analyzed using electron microscopy. Carbonyl compounds were identified by mass spectrometry. The elemental carbon content of the bulk CNT-containing filaments was 1.5 to 5.2 wt%. CNT-containing filaments released up to 10(10) ultrafine (d <100 nm) particles/g printed and 10(6) to 10(8) respirable (d ~0.5 to 2 mum) particles/g printed. From microscopy, 1% of the emitted respirable polymer particles contained visible CNTs. Carbonyl emissions were observed above the limit of detection (LOD) but were below the limit of quantitation (LOQ). Modeling indicated that for all filaments, the average proportional lung deposition of CNT-containing polymer particles was 6.5%, 5.7%, and 7.2% for the head airways, tracheobronchiolar, and pulmonary regions, respectively. If CNT-containing polymer particles are hazardous, it would be prudent to control emissions during use of these filaments. This article is protected by copyright. All rights reserved. |
Pathology in practice
Edwards EE , Birch SM , Hoppes SM , Keating MK , Stoica G . J Am Vet Med Assoc 2018 253 (4) 423-426 A 7-month-old 370-g (0.81-lb) sexually intact female common marmoset (Callithrix jacchus) that was kept as a pet was taken to a referring veterinarian after a sudden onset of lethargy and inappetence. A diagnosis of pulmonary consolidation and colic was made, and the owners were instructed to administer supportive treatments to the marmoset at home. The next day, the animal's condition slowly worsened with development of neurologic signs including disorientation, trembling, and ataxia. The marmoset was brought to the Zoological Medicine Service at Texas A&M University on an emergency basis but died during hospitalization the next day, approximately 72 hours following the initial onset of clinical signs. The marmoset was submitted for necropsy. The marmoset lived with an 11-month-old male marmoset and had access to an outdoor porch allowing for indirect contact with a feral cat. Human contact with the marmoset was limited to the 2 owners and the referring veterinarian and veterinary staff. According to the owner, not long after the death of the female marmoset, the male marmoset from the household developed similar clinical signs and died shortly thereafter. A necropsy was not performed on that animal. |
Analysis of crystalline silica aerosol using portable raman spectrometry: Feasibility of near real-time measurement
Zheng L , Kulkarni P , Birch ME , Ashley K , Wei S . Anal Chem 2018 90 (10) 6229-6239 A Raman spectroscopy based method has been developed for measurement of trace airborne concentrations of respirable crystalline silica (RCS) using various aerosol sampling and analysis techniques. Three aerosol microconcentration techniques were investigated for effective coupling of collected particulate samples with micro-Raman spectroscopy: (i) direct analysis on a particulate filter after focused aerosol collection using a converging nozzle; (ii) analysis of dried particulate deposit on a filter obtained directly from the aerosol phase using the Spotsampler device; and (iii) analysis of a dried spot (approximately 1.3 mm diameter) obtained by redepositing the particulate sample, after low-temperature plasma ashing of the filter sample. The deposition characteristics (i.e., spot diameter, shape, and deposit uniformity) of each technique were investigated. Calibration curves were constructed and detection limits were estimated for alpha-quartz using the A1 Raman Si-O-Si stretching-bending phonon mode at 465 cm-1. The measurement sensitivity could be substantially improved by increasing the signal integration time and by reducing the particle deposition area. Detection limits in the range of 8-55 ng could be achieved by microconcentrating the aerosol sample over a spot measuring 400-1000 microm in diameter. These detection limits were two to three orders of magnitude lower compared to those attainable using current standardized X-ray diffraction and infrared spectroscopy methods. The low detection limits suggest that near real-time measurements of RCS could be achieved with limits of quantification ranging from 2 to 18.5 microg/m3 (at 10 min collection time and 1.2 L/min sampling flow rate), depending on microconcentration technique used. The method was successfully extended to the measurement of alpha-quartz air concentration in representative workplace aerosol samples. This study demonstrates the potential of portable micro-Raman spectroscopy for near-real time measurement of trace RCS in air. |
Association of pulmonary, cardiovascular, and hematologic metrics with carbon nanotube and nanofiber exposure among U.S. workers: a cross-sectional study
Schubauer-Berigan MK , Dahm MM , Erdely A , Beard JD , Eileen Birch M , Evans DE , Fernback JE , Mercer RR , Bertke SJ , Eye T , de Perio MA . Part Fibre Toxicol 2018 15 (1) 22 BACKGROUND: Commercial use of carbon nanotubes and nanofibers (CNT/F) in composites and electronics is increasing; however, little is known about health effects among workers. We conducted a cross-sectional study among 108 workers at 12 U.S. CNT/F facilities. We evaluated chest symptoms or respiratory allergies since starting work with CNT/F, lung function, resting blood pressure (BP), resting heart rate (RHR), and complete blood count (CBC) components. METHODS: We conducted multi-day, full-shift sampling to measure background-corrected elemental carbon (EC) and CNT/F structure count concentrations, and collected induced sputum to measure CNT/F in the respiratory tract. We measured (nonspecific) fine and ultrafine particulate matter mass and count concentrations. Concurrently, we conducted physical examinations, BP measurement, and spirometry, and collected whole blood. We evaluated associations between exposures and health measures, adjusting for confounders related to lifestyle and other occupational exposures. RESULTS: CNT/F air concentrations were generally low, while 18% of participants had evidence of CNT/F in sputum. Respiratory allergy development was positively associated with inhalable EC (p=0.040) and number of years worked with CNT/F (p=0.008). No exposures were associated with spirometry-based metrics or pulmonary symptoms, nor were CNT/F-specific metrics related to BP or most CBC components. Systolic BP was positively associated with fine particulate matter (p-values: 0.015-0.054). RHR was positively associated with EC, at both the respirable (p=0.0074) and inhalable (p=0.0026) size fractions. Hematocrit was positively associated with the log of CNT/F structure counts (p=0.043). CONCLUSIONS: Most health measures were not associated with CNT/F. The positive associations between CNT/F exposure and respiratory allergies, RHR, and hematocrit counts may not be causal and require examination in other studies. |
Quantification of carbon nanotubes by Raman analysis
Lynch JA , Birch QT , Ridgway TH , Birch ME . Ann Work Expo Health 2018 62 (5) 604-612 The increasing prevalence of carbon nanotubes (CNTs) in manufacturing and research environments, together with the potential exposure risks, necessitates development of reliable and accurate monitoring methods for these materials. We examined quantification of CNTs by two distinct methods based on Raman spectroscopy. First, as measured by the Raman peak intensity of aqueous CNT suspensions, and second, by Raman mapping of air filter surfaces onto which CNTs were collected as aerosols or applied as small-area (0.05 cm2) deposits. Correlation (R2 = 0.97) between CNT concentration and Raman scattering intensity for suspensions in cuvettes was found over a concentration range from about 2 to 10 microg/ml, but measurement variance precludes practical determination of a calibration curve. Raman mapping of aerosol sample filter surfaces shows correlation with CNT mass when the surface density is relatively high (R2 = 0.83 and 0.95 above about 5 microg total mass on filter), while heterogeneity of CNT deposition makes obtaining representative maps of lower density samples difficult. This difficulty can be mitigated by increasing the area mapped relative to the total sample area, improving both precision and the limit of detection (LOD). For small-area deposits, detection of low masses relevant to occupational monitoring can be achieved, with an estimated LOD of about 50 ng. |
Carbon nanotube and nanofiber exposure and sputum and blood biomarkers of early effect among U.S. workers
Beard JD , Erdely A , Dahm MM , de Perio MA , Birch ME , Evans DE , Fernback JE , Eye T , Kodali V , Mercer RR , Bertke SJ , Schubauer-Berigan MK . Environ Int 2018 116 214-228 BACKGROUND: Carbon nanotubes and nanofibers (CNT/F) are increasingly used for diverse applications. Although animal studies suggest CNT/F exposure may cause deleterious health effects, human epidemiological studies have typically been small, confined to single workplaces, and limited in exposure assessment. OBJECTIVES: We conducted an industrywide cross-sectional epidemiological study of 108 workers from 12 U.S. sites to evaluate associations between occupational CNT/F exposure and sputum and blood biomarkers of early effect. METHODS: We assessed CNT/F exposure via personal breathing zone, filter-based air sampling to measure background-corrected elemental carbon (EC) (a CNT/F marker) mass and microscopy-based CNT/F structure count concentrations. We measured 36 sputum and 37 blood biomarkers. We used factor analyses with varimax rotation to derive factors among sputum and blood biomarkers separately. We used linear, Tobit, and unconditional logistic regression models to adjust for potential confounders and evaluate associations between CNT/F exposure and individual biomarkers and derived factors. RESULTS: We derived three sputum and nine blood biomarker factors that explained 78% and 67%, respectively, of the variation. After adjusting for potential confounders, inhalable EC and total inhalable CNT/F structures were associated with the most sputum and blood biomarkers, respectively. Biomarkers associated with at least three CNT/F metrics were 72kDa type IV collagenase/matrix metalloproteinase-2 (MMP-2), interleukin-18, glutathione peroxidase (GPx), myeloperoxidase, and superoxide dismutase (SOD) in sputum and MMP-2, matrix metalloproteinase-9, metalloproteinase inhibitor 1/tissue inhibitor of metalloproteinases 1, 8-hydroxy-2'-deoxyguanosine, GPx, SOD, endothelin-1, fibrinogen, intercellular adhesion molecule 1, vascular cell adhesion protein 1, and von Willebrand factor in blood, although directions of associations were not always as expected. CONCLUSIONS: Inhalable rather than respirable CNT/F was more consistently associated with fibrosis, inflammation, oxidative stress, and cardiovascular biomarkers. |
Analytical high-resolution electron microscopy reveals organ-specific nanoceria bioprocessing
Graham UM , Yokel RA , Dozier AK , Drummy L , Mahalingam K , Tseng MT , Birch E , Fernback J . Toxicol Pathol 2018 46 (1) 47-61 This is the first utilization of advanced analytical electron microscopy methods, including high-resolution transmission electron microscopy, high-angle annular dark field scanning transmission electron microscopy, electron energy loss spectroscopy, and energy-dispersive X-ray spectroscopy mapping to characterize the organ-specific bioprocessing of a relatively inert nanomaterial (nanoceria). Liver and spleen samples from rats given a single intravenous infusion of nanoceria were obtained after prolonged (90 days) in vivo exposure. These advanced analytical electron microscopy methods were applied to elucidate the organ-specific cellular and subcellular fate of nanoceria after its uptake. Nanoceria is bioprocessed differently in the spleen than in the liver. |
Exposure assessments for a cross-sectional epidemiologic study of US carbon nanotube and nanofiber workers
Dahm MM , Schubauer-Berigan MK , Evans DE , Birch ME , Bertke S , Beard JD , Erdely A , Fernback JE , Mercer RR , Grinshpun SA . Int J Hyg Environ Health 2018 221 (3) 429-440 BACKGROUND: Recent animal studies have suggested the potential for wide-ranging health effects resulting from exposure to carbon nanotubes and nanofibers (CNT/F). To date, no studies in the US have directly examined the relationship between occupational exposure and potential human health effects. OBJECTIVES: Our goal was to measure CNT/F exposures among US workers with representative job types, from non-exposed to highly exposed, for an epidemiologic study relating exposure to early biologic effects. METHODS: 108 participants were enrolled from 12 facilities across the US. Personal, full-shift exposures were assessed based on the mass of elemental carbon (EC) at the respirable and inhalable aerosol particle size fractions, along with quantitatively characterizing CNT/F and estimating particle size via transmission electron microscopy (TEM). Additionally, sputum and dermal samples were collected and analyzed to determine internal exposures and exposures to the hands/wrists. RESULTS: The mean exposure to EC was 1.00mug/m(3) at the respirable size fraction and 6.22mug/m(3) at the inhalable fraction. Analysis by TEM found a mean exposure of 0.1275 CNT/F structures/cm(3), generally to agglomerated materials between 2 and 10mum. Internal exposures to CNT/F via sputum analysis were confirmed in 18% of participants while approximately 70% had positive dermal exposures. CONCLUSIONS: We demonstrated the occurrence of a broad range of exposures to CNT/F within 12 facilities across the US. Analysis of collected sputum indicated internal exposures are currently occurring within the workplace. This is an important first step in determining if exposures in the workforce have any acute or lasting health effects. |
Effectiveness of laboratory practices to reducing patient misidentification due to specimen labeling errors at the time of specimen collection in healthcare settings: LMBP Systematic Review
Sandhu P , Bandyopadhyay K , Ernst DJ , Hunt W , Taylor TH Jr , Birch R , Krolak J , Geaghan S . J Appl Lab Med 2017 2 (2) 244-258 Background: Specimen labeling errors have long plagued the laboratory industry putting patients at risk of transfusion-related death, medication errors, misdiagnosis, and patient mismanagement. Many interventions have been implemented and deemed to be effective in reducing sample error rates. The objective of this review was to identify and evaluate the effectiveness of laboratory practices/ interventions to develop evidence based recommendations for the best laboratory practices to reduce labeling errors. Content: The standardized LMBP A-6 methods were used to conduct this systematic review. Total evidence included 12 studies published during the time periods of 1980 to September 2015. Combined data from seven studies found that the interventions developed as a result of improved communication and collaboration between the laboratory and clinical staff resulted in substantial decrease in specimen labeling errors (Median relative percent change in labeling errors: -75.86; IQI: -84.77, -58.00). Further data from subset of four studies showed a significant decrease in specimen labeling errors after the institution of the standardized specimen labeling protocols (Median relative percent decrease in specimen labeling errors: -72.45; IQI: -83.25, -46.50). Summary: Based on the evidence included in this review, the interventions that enhance the communication and collaboration between laboratory and healthcare professionals can decrease the specimen identification errors in healthcare settings. However, more research is needed to make the conclusion on the effectiveness of other evaluated practices in this review including training and education of the specimen collection staff, audit and feedback of labeling errors, and implementation of new technology (other than barcoding). |
In Vivo Toxicity Assessment of Occupational Components of the Carbon Nanotube Life Cycle To Provide Context to Potential Health Effects
Bishop L , Cena L , Orandle M , Yanamala N , Dahm MM , Birch ME , Evans DE , Kodali VK , Eye T , Battelli L , Zeidler-Erdely PC , Casuccio G , Bunker K , Lupoi JS , Lersch TL , Stefaniak AB , Sager T , Afshari A , Schwegler-Berry D , Friend S , Kang J , Siegrist KJ , Mitchell CA , Lowry DT , Kashon ML , Mercer RR , Geraci CL , Schubauer-Berigan MK , Sargent LM , Erdely A . ACS Nano 2017 11 (9) 8849-8863 Pulmonary toxicity studies on carbon nanotubes focus primarily on as-produced materials and rarely are guided by a life cycle perspective or integration with exposure assessment. Understanding toxicity beyond the as-produced, or pure native material, is critical, due to modifications needed to overcome barriers to commercialization of applications. In the first series of studies, the toxicity of as-produced carbon nanotubes and their polymer-coated counterparts was evaluated in reference to exposure assessment, material characterization, and stability of the polymer coating in biological fluids. The second series of studies examined the toxicity of aerosols generated from sanding polymer-coated carbon-nanotube-embedded or neat composites. Postproduction modification by polymer coating did not enhance pulmonary injury, inflammation, and pathology or in vitro genotoxicity of as-produced carbon nanotubes, and for a particular coating, toxicity was significantly attenuated. The aerosols generated from sanding composites embedded with polymer-coated carbon nanotubes contained no evidence of free nanotubes. The percent weight incorporation of polymer-coated carbon nanotubes, 0.15% or 3% by mass, and composite matrix utilized altered the particle size distribution and, in certain circumstances, influenced acute in vivo toxicity. Our study provides perspective that, while the number of workers and consumers increases along the life cycle, toxicity and/or potential for exposure to the as-produced material may greatly diminish. |
From dose to response: In vivo nanoparticle processing and potential toxicity
Graham UM , Jacobs G , Yokel RA , Davis BH , Dozier AK , Birch ME , Tseng MT , Oberdorster G , Elder A , DeLouise L . Adv Exp Med Biol 2017 947 71-100 Adverse human health impacts due to occupational and environmental exposures to manufactured nanoparticles are of concern and pose a potential threat to the continued industrial use and integration of nanomaterials into commercial products. This chapter addresses the inter-relationship between dose and response and will elucidate on how the dynamic chemical and physical transformation and breakdown of the nanoparticles at the cellular and subcellular levels can lead to the in vivo formation of new reaction products. The dose-response relationship is complicated by the continuous physicochemical transformations in the nanoparticles induced by the dynamics of the biological system, where dose, bio-processing, and response are related in a non-linear manner. Nanoscale alterations are monitored using high-resolution imaging combined with in situ elemental analysis and emphasis is placed on the importance of the precision of characterization. The result is an in-depth understanding of the starting particles, the particle transformation in a biological environment, and the physiological response. |
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