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1.
Toxicol Ind Health ; 37(3): 124-133, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33506748

ABSTRACT

Some industrial crane control panels were historically equipped with chrysotile-containing arc chutes. Because of the paucity of data regarding potential exposure from such equipment, we used a simulation approach to quantify the release of chrysotile from arc chutes in two functional 1970s-era industrial crane control panels during operation and maintenance. Two experienced operators separately simulated operation of crane controls under load; one of these operators then simulated two arc chute maintenance protocols: sanding (protocol 1) and scraping, sanding, and blowing (protocol 2). The original arc chutes contained approximately 36% chrysotile. Personal breathing zone (PBZ) (n = 8) and area samples (n = 8) were collected and analyzed using phase contrast microscopy (PCM) and transmission electron microscopy. PCM-equivalent (PCME) concentrations were derived, from which 8-h time-weighted averages (TWA) were calculated. During operation, chrysotile was identified in one of the four PBZ samples, equivalent to a PCME concentration of 0.012 f/cm3 (8-h TWA: 0.011 f/cm3). During protocols 1 and 2, chrysotile was identified in all PBZ samples (n = 4); PCME concentrations (and corresponding 8-h TWA) were <0.013 and 0.021 f/cm3 (0.001 and 0.004 f/cm3) and 0.013 and 0.017 f/cm3 (0.003 f/cm3), respectively. Many of the airborne chrysotile fibers had matrix attached, supporting the low exposure potential during this work. These data indicate very low, if any, exposures to chrysotile asbestos during the simulated scenarios. In addition, these data could assist with refining assumptions in exposure reconstruction and inform the state-of-the science on low-level chrysotile exposure.


Subject(s)
Air Pollutants, Occupational/analysis , Asbestos, Serpentine/analysis , Occupational Exposure/analysis , Construction Materials , Humans , Industry , Inhalation Exposure/analysis , Male , Wisconsin
2.
Toxicol Rep ; 4: 113-122, 2017.
Article in English | MEDLINE | ID: mdl-28959632

ABSTRACT

Recently described scientific literature has identified the airborne presence of 2,3-butanedione (diacetyl) and 2,3-pentanedione at concentrations approaching or potentially exceeding the current American Conference of Industrial Hygienists' (ACGIH) Threshold Limit Values (TLVs) at commercial coffee roasting and production facilities. Newly established National Institutes of Occupational Safety and Health (NIOSH) Recommended Exposure Limits for diacetyl and 2,3-pentanedione are even more conservative. Chronic exposure to these alpha-diketones at elevated airborne concentrations has been associated with lung damage, specifically bronchiolitis obliterans, most notably in industrial food processing facilities. Workers at a large commercial coffee roaster were monitored for both eight-hour and task-based, short-term, 15-min sample durations for airborne concentrations of these alpha-diketones during specific work processes, including the coffee bean roasting, blending and grinding processes, during two separate 8-h work periods. Additionally, the authors performed real-time Fourier transform infrared spectroscopy (FTIR) analysis of the workers' breathing zone as well as the area workplace air for the presence of organic compounds to determine the sources, as well as quantitate and identify various organic compounds proximal to the roasting and grinding processes. Real-time FTIR measurements provided both the identification and quantitation of diacetyl and 2,3-pentanedione, as well as other organic compounds generated during coffee bean roasting and grinding operations. Airborne concentrations of diacetyl in the workers' breathing zone, as eight-hour time-weighted averages were less than the ACGIH TLVs for diacetyl, while concentrations of 2,3-pentanedione were below the limit of detection in all samples. Short-term breathing zone samples revealed airborne concentrations for diacetyl that exceeded the ACGIH short-term exposure limit of 0.02 parts per million (ppm) in two samples collected on a grinder operator. FTIR analysis of air samples collected from both the workers' breathing zone and area air samples revealed low concentrations of various organics with diacetyl and 2,3-pentanedione at concentrations less than the limit of detection for the FTIR methods. Neither the breathing zone nor area air samples measured using the FTIR reflected airborne concentrations of organic compounds that, when detected, approached the ACGIH TLVs or regulatory standards, when available. FTIR analysis of headspace of ground coffee beans revealed ppm concentrations of expected alpha diketones, carbon monoxide and other volatile organic compounds (VOCs). Coffee roasting and grinding, with adequate building ventilation and typical roasted bean handling and grinding, appears to generate very low, if any, concentrations of diacetyl and 2,3-pentanedione in the workers' breathing zones. This study also confirmed via FTIR that roasted coffee beans naturally generate alpha-diketones and other organic compounds as naturally occurring compounds resultant of the roasting and then released during the grinding process.

3.
ACS Med Chem Lett ; 4(6): 560-4, 2013 Jun 13.
Article in English | MEDLINE | ID: mdl-24900709

ABSTRACT

The objective of the described research effort was to identify a novel serotonin and norepinephrine reuptake inhibitor (SNRI) with improved norepinephrine transporter activity and acceptable metabolic stability and exhibiting minimal drug-drug interaction. We describe herein the discovery of a series of 3-substituted pyrrolidines, exemplified by compound 1. Compound 1 is a selective SNRI in vitro and in vivo, has favorable ADME properties, and retains inhibitory activity in the formalin model of pain behavior. Compound 1 thus represents a potential new probe to explore utility of SNRIs in central nervous system disorders, including chronic pain conditions.

4.
Obstet Gynecol ; 116(1): 140-143, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20567180

ABSTRACT

There is growing recognition of the importance and potential benefit of information technology and electronic medical records in providing quality care for women. Incorporation of obstetrician-gynecologist-specific requirements by electronic medical record vendors is essential to achieve appropriate electronic medical record functionality for obstetrician-gynecologists. Obstetricians and gynecologists record and document patient care in ways that are unique to medicine. Current electronic medical record systems are often limited in their usefulness for the practice of obstetrics and gynecology because of the absence of obstetrician-gynecologist specialty-specific requirements and functions. The Certification Commission on Health Information Technology is currently the only federally recognized body for certification of electronic medical record systems. As Certification Commission on Health Information Technology expands the certification criteria for electronic medical records, the special requirements identified in this report will be used as a framework for developing obstetrician-gynecologist specialty-specific criteria to be incorporated into the Certification Commission on Health Information Technology endorsement for electronic medical records used by obstetrician-gynecologists.


Subject(s)
Electronic Health Records/standards , Gynecology , Obstetrics , Certification , Decision Making , Practice Guidelines as Topic , United States
10.
Am J Physiol Endocrinol Metab ; 287(5): E820-7, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15198935

ABSTRACT

Acute nitric oxide (NO) inhibits angiotensin II (ANG II)-stimulated aldosterone synthesis in zona glomerulosa (ZG) cells. In this study, we investigated the effects of chronic administration of NO on the ANG II receptor type 1 (AT1) expression and aldosterone synthesis. ZG cells were treated daily with DETA NONOate (10(-4) M), an NO donor, for 0, 12, 24, 48, 72, and 96 h. Chinese hamster ovary (CHO) cells, stably transfected with the AT1B receptor, were used as a positive control. Western blot analysis indicated that AT1 receptor expression was decreased as a function of time of NO administration in both CHO and ZG cells. ANG II binding to its receptors was determined by radioligand binding. NO treatment of ZG cells for 96 h resulted in a decrease in ANG II binding compared with control. The receptor density was decreased to 1,864 +/- 129 fmol/mg protein from 3,157 +/- 220 fmol/mg protein (P < 0.005), but the affinity was not changed (1.95 +/- 0.22 vs. 1.88 +/- 0.21 nM). Confocal Raman microspectroscopy and immunocytochemistry both confirmed that the expression of AT1 receptors in ZG cells decreased with chronic NO administration. In addition, chronic NO administration also decreased the expression of cholesterol side-chain cleavage enzyme in ZG cells and inhibited ANG II- and 25-hydroxycholesterol-stimulated aldosterone synthesis in ZG cells. This study demonstrates that chronic administration of NO inhibits aldosterone synthesis in ZG cells by downregulation of the expression of both AT1 receptors and cholesterol side-chain cleavage enzyme.


Subject(s)
Aldosterone/biosynthesis , Nitric Oxide/administration & dosage , Nitric Oxide/physiology , Receptor, Angiotensin, Type 1/metabolism , Zona Glomerulosa/metabolism , Angiotensin II/metabolism , Animals , Blotting, Western , CHO Cells/drug effects , CHO Cells/metabolism , Cattle , Cells, Cultured , Cholesterol Side-Chain Cleavage Enzyme/metabolism , Cricetinae , Cricetulus , Dose-Response Relationship, Drug , Down-Regulation/drug effects , Down-Regulation/physiology , Drug Administration Schedule , Humans , Immunohistochemistry , Spectrum Analysis, Raman , Zona Glomerulosa/cytology , Zona Glomerulosa/drug effects
11.
Anal Biochem ; 322(2): 198-207, 2003 Nov 15.
Article in English | MEDLINE | ID: mdl-14596828

ABSTRACT

A method using confocal Raman microspectroscopy for the detection of cellular proteins in single intact cells was developed. Two approaches were used to improve the detection of these cellular components. First, compounds with high Raman scattering were investigated for potential use as Raman labels. Raman labels were conjugated to either biomolecules or biotin and used as markers in the detection of cellular enzymes and receptors. Second, silver colloids were used to increase the surface-enhanced Raman scatter (SERS) of these Raman labels. Cresyl violet and dimethylaminoazobenzene are Raman labels that provide very sensitive SERS detection by a confocal Raman microscope with a HeNe laser at wavelength of 632.8 nm. The detection of 12-lipoxygenase and cyclooxygenase-1 in single bovine coronary artery endothelial cells and the binding of angiotensin II to its receptors in zona glomerulosa cells was demonstrated.


Subject(s)
Coloring Agents/chemistry , Proteins/analysis , Spectrum Analysis, Raman/methods , Angiotensin II/analysis , Animals , Arachidonate 12-Lipoxygenase/analysis , Benzoxazines , Biotin/chemistry , Cattle , Cells, Cultured , Citrates/chemistry , Colloids/chemistry , Coronary Vessels/cytology , Coronary Vessels/enzymology , Cyclooxygenase 1 , Endothelium, Vascular/cytology , Endothelium, Vascular/enzymology , Fluorescent Antibody Technique/methods , Isoenzymes/analysis , Microscopy, Confocal/instrumentation , Microscopy, Confocal/methods , Oxazines/chemistry , Prostaglandin-Endoperoxide Synthases/analysis , Proteins/chemistry , Receptors, Angiotensin/metabolism , Sensitivity and Specificity , Silver Compounds/chemistry , Zona Glomerulosa , p-Dimethylaminoazobenzene/chemistry
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