Detection of Viruses from Bioaerosols Using Anion Exchange Resin.

This protocol demonstrates a customized bioaerosol sampling method for viruses. In this system, anion exchange resin is coupled with liquid impingement-based air sampling devices for efficacious concentration of negatively-charged viruses from bioaerosols. Thus, the resin serves as an additional concentration step in the bioaerosol sampling workflow. Nucleic acid extraction of the viral particles is then performed directly from the anion exchange resin, with the resulting sample suitable for molecular analyses. Further, this protocol describes a custom-built bioaerosol chamber capable of generating virus-laden bioaerosols under a variety of environmental conditions and allowing for continuous monitoring of environmental variables such as temperature, humidity, wind speed, and aerosol mass concentration. The main advantage of using this protocol is increased sensitivity of viral detection, as assessed via direct comparison to an unmodified conventional liquid impinger. Other advantages include the potential to concentrate diverse negatively-charged viruses, the low cost of anion exchange resin (~$0.14 per sample), and ease of use. Disadvantages include the inability of this protocol to assess infectivity of resin-adsorbed viral particles, and potentially the need for the optimization of the liquid sampling buffer used within the impinger.

Personal exposure of dairy workers to dust, endotoxin, muramic acid, ergosterol, and ammonia on large-scale dairies in the high plains Western United States.

Dairy workers experience a high degree of bioaerosol exposure, composed of an array of biological and chemical constituents, which have been tied to adverse health effects. A better understanding of the variation in the magnitude and composition of exposures by task is needed to inform worker protection strategies. To characterize the levels and types of exposures, 115 dairy workers grouped into three task categories on nine farms in the high plains Western United States underwent personal monitoring for inhalable dust, endotoxin, 3-hydroxy fatty acids (3-OHFA), muramic acid, ergosterol, and ammonia through one work shift. Eighty-nine percent of dairy workers were exposed to endotoxin at concentrations exceeding the recommended exposure guidelines (adjusted for a long work shift). The proportion of workers with exposures exceeding recommended guidelines was lower for inhalable dust (12%), and ammonia (1%). Ergosterol exposures were only measurable on 28% of samples, primarily among medical workers and feed handlers. Milking parlor workers were exposed to significantly higher inhalable dust, endotoxin, 3-OHFA, ammonia, and muramic acid concentrations compared to workers performing other tasks. Development of large modern dairies has successfully made progress in reducing worker exposures and lung disease prevalence. However, exposure to endotoxin, dust, and ammonia continues to present a significant risk to worker health on North American dairies, especially for workers in milking parlors. This study was among the first to concurrently evaluate occupational exposure to assayable endotoxin (lipid A), 3-hydroxy fatty acids or 3-OHFA (a chemical measure of cell bound and noncell-bound endotoxins), muramic acid, ergosterol, and ammonia among workers on Western U.S. dairies. There remains a need for cost-effective, culturally acceptable intervention strategies integrated in OHS Risk Management and production systems to further optimize worker health and farm productivity.

Modeling pancreatic tumor motion using 4-dimensional computed tomography and surrogate markers.

PURPOSE: To assess intrafractional positional variations of pancreatic tumors using 4-dimensional computed tomography (4D-CT), their impact on gross tumor volume (GTV) coverage, the reliability of biliary stent, fiducial seeds, and the real-time position management (RPM) external marker as tumor surrogates for setup of respiratory gated treatment, and to build a correlative model of tumor motion. METHODS AND MATERIALS: We analyzed the respiration-correlated 4D-CT images acquired during simulation of 36 patients with either a biliary stent (n=16) or implanted fiducials (n=20) who were treated with RPM respiratory gated intensity modulated radiation therapy for locally advanced pancreatic cancer. Respiratory displacement relative to end-exhalation was measured for the GTV, the biliary stent, or fiducial seeds, and the RPM marker. The results were compared between the full respiratory cycle and the gating interval. Linear mixed model was used to assess the correlation of GTV motion with the potential surrogate markers. RESULTS: The average ± SD GTV excursions were 0.3 ± 0.2 cm in the left-right direction, 0.6 ± 0.3 cm in the anterior-posterior direction, and 1.3 ± 0.7 cm in the superior-inferior direction. Gating around end-exhalation reduced GTV motion by 46% to 60%. D95% was at least the prescribed 56 Gy in 76% of patients. GTV displacement was associated with the RPM marker, the biliary stent, and the fiducial seeds. The correlation was better with fiducial seeds and with biliary stent. CONCLUSIONS: Respiratory gating reduced the margin necessary for radiation therapy for pancreatic tumors. GTV motion was well correlated with biliary stent or fiducial seed displacements, validating their use as surrogates for daily assessment of GTV position during treatment. A patient-specific internal target volume based on 4D-CT is recommended both for gated and not-gated treatment; otherwise, our model can be used to predict the degree of GTV motion.

Renewable energy and occupational health and safety research directions: a white paper from the Energy Summit, Denver Colorado, April 11-13, 2011.

Renewable energy production may offer advantages to human health by way of less pollution and fewer climate-change associated ill-health effects. Limited data suggests that renewable energy will also offer benefits to workers in the form of reduced occupational injury, illness and deaths. However, studies of worker safety and health in the industry are limited. The Mountain and Plains Education and Research Center (MAP ERC) Energy Summit held in April 2011 explored issues concerning worker health and safety in the renewable energy industry. The limited information on hazards of working in the renewable energy industry emphasizes the need for further research. Two basic approaches to guiding both prevention and future research should include: (1) applying lessons learned from other fields of occupational safety and health, particularly the extractive energy industry; and (2) utilizing knowledge of occupational hazards of specific materials and processes used in the renewable energy industry.

Systematic review of respiratory health among dairy workers.

The dairy industry is changing on a global scale with larger, more efficient operations. The impact of this change on worker health and safety, specifically, associations between occupational lung disease and inhalation exposures, has yet to be reported in a comprehensive review of the scientific literature. Therefore, a three-tier process was used to identify information using a keyword search of online databases of scientific literature. Of the 147 citations reviewed, 52 met initial screening criteria, and 30 were included in this review. Dairy workers experience lung conditions such as asthma, chronic obstructive pulmonary disease, hypersensitivity pneumonitis, chronic bronchitis, and cancer. Recent pulmonary function studies have identified obstructive lung changes among dairy farm workers. The increased scale of dairy production with significant changes in technology and work practices has altered inhalation exposure patterns among dairy workers. The inhalation exposure in the dairy work environment may elicit differing inflammatory responses in relation to timing of initial exposure as well as to repeated exposures. Few studies have measured inhalation exposure while simultaneously assessing the impact of the exposure on lung function of dairy farm workers. Even fewer studies have been implemented to assess the impact of aerosol control technology to reduce inhalation exposure. Future research should evaluate worker exposure to aerosols through a task-based approach while utilizing novel methods to assess inhalation exposure and associated inflammatory responses. Finally, potential solutions should be developed and tested to reduce inhalation exposure to inflammatory agents and respiratory diseases in the dairy farm work environment.

Pulmonary function reductions among potentially susceptible subgroups of agricultural workers in Colorado and Nebraska.

OBJECTIVE: Organic dust inhalation has been associated with adverse respiratory responses among agricultural workers. We evaluated factors that may confer increased susceptibility to these health effects. METHODS: We quantified personal work shift exposures to inhalable dust, endotoxin, and its 3-hydroxy fatty acid constituents, and evaluated changes in pulmonary function among 137 grain elevator, cattle feedlot, dairy, and corn farm workers. RESULTS: Increased dust exposure was associated with work shift reductions in lung function. Although interpretation is limited because of small samples, a suggestion of stronger exposure-response relationships was observed among smokers, as well as workers reporting pesticide/herbicide application, asthma, or allergies, and those with genetic polymorphisms (TLR4) (Pinteraction ≤ 0.05). CONCLUSIONS: A better understanding of factors leading to increased susceptibility of adverse respiratory outcomes is needed to optimize exposure reduction strategies and develop more comprehensive wellness programs.

Paracingulate sulcus asymmetry; sex difference, correlation with semantic fluency and change over time in adolescent onset psychosis.

The left paracingulate sulcus (PCS) is longer than the right and the adjacent cortex is activated by the generation of words. In adult patients with chronic schizophrenia the anatomical asymmetry is reduced. In 35 controls and 38 adolescents with schizophrenia or schizoaffective disorder (mean age = 16 years) we found that semantic verbal fluency correlated with leftward PCS asymmetry in controls but not in patients. At intake, PCS length did not differ between patients and controls, but at follow-up (13 controls, 10 patients, mean age = 18 years) PCS asymmetry (comprising both increasing left and decreasing right length) increased significantly, the increase was greater in males than in females, and there was a trend for a diagnosis * sex * side * time interaction such that in controls leftward PCS asymmetry increased, while in patients of both sexes there was convergence toward symmetry. Thus sulcal anatomy develops differentially in the two sexes during adolescence, and the pattern of asymmetric sex-dependent change over time may distinguish patients with psychosis from controls. Greater change in asymmetry during adolescence may explain earlier age of onset in males and greater deficits in verbal fluency.

Pelviureteric peristaltic contractions in diabetic rats.

The effects of strepozotocin (STZ)-induced diabetes on the spontaneous peristaltic contractions in the upper urinary tract (UUT) of the rat were examined by simultaneously recording the tension in the proximal and distal regions of the renal pelvis and the proximal ureter. All regions of the UUT of diabetic rats contracted at a frequency similar to the contraction frequency of age-matched control rats. In contrast, contraction amplitudes in the proximal and distal renal pelvis and ureter of diabetic rats were 36%, 135% and 121% larger than the equivalent contractions recorded in control rats resulting in a significant increases in the motility index (MI amplitude x frequency) in all 3 regions. Capsaicin (10 microM), substance P (SP 2 microM) and neurokinin A (NKA 2 microM) caused a transient increase in MI in both control and STZ-induced diabetic rats. The rise in basal tension in the proximal and distal renal pelvis evoked by capsaicin, SP or NKA was also significantly greater in the diabetic rats when compared with controls. In contrast, human calcitonin-gene related peptide (hCGRP) produced a relatively small transient inhibition of UUT motility which was little affected by STZ treatment. These results suggest that capsaicin predominantly releases tachykinins from intrinsic sensory nerves in both non-diabetic and STZ-induced diabetic rats. We speculate that the supersensitivity of the diabetic UUT to capsaicin, NKA and SP 8-10 weeks after STZ treatment could be arising from an earlier development of sensory neuropathy.

The response of blood glucose, ketones, and plasma nonesterified fatty acids to fasting and epinephrine injection in infants and children

Blood ketone, blood glucose and plasma NEFA concentrations after a 24 hour fast werre studied in 181 infants and children from birth to 12 years of age. The same measurements following epinephrine injections were made in 89 infants and children from birth to 14 years. It was found that infants under 36 hours were more resistant to ketosis on fasting than infants 2 to 6 days of age whose ketosis became almost as severe as that of subjects aged 1 week to 4 years. The difference in response between these two newborn groups was found to be associated with large stores of liver glycogen in the younger group. Infants under 36 hours did not appear to have any impairment of fat catabolism as indicated by a progressive rise in blood ketone levels on more extended fasts and by their normal NEFA elevation after epinephrine. Subjects 1 week to 4 years of age developed more ketosis on fasting than did older children. It was shown that this was not related to differences in excretion or utilization of ketone bodies, indicating that variation in ketone production was the factor responsible. Blood sugar levels below 40 mg. percent occurred in 45 of 123 subjects under 6 months of age who were fasted for 24 hours. With one exception, blood sugar below this level was not found in subjects over 7 months of age(AU)