Inhalational volatile anaesthetic agents: the atmospheric scientists' viewpoint.

All sectors of society must reduce their carbon footprint to mitigate climate change, and the healthcare community is no exception. This narrative review focuses on the environmental concerns associated with the emissions of volatile anaesthetic agents, some of which are potent greenhouse gases. This review provides an understanding of the global warming potential metric, as well as the concepts of atmospheric lifetime and radiative efficiency. The state of knowledge of the environmental impact and possible climate forcing of emitted volatile anaesthetic agents are reviewed. Additionally, the review discusses how climate metrics can guide mitigation strategies to reduce emissions and suggests present and future options for mitigating the climate impact.

A clinical and histopathological comparison of the effectiveness of salicylic acid to a compound of inorganic acids for the treatment of digital dermatitis in cattle.

Bovine digital dermatitis (DD) is a painful infectious disease, causing lameness, reduced animal welfare, and production losses in dairy herds. The main factors contributing to DD are an infection with Treponema spp. and poor hygiene. Topical treatment has primarily consisted of antibiotics; however, the demand for effective nonantibiotic alternatives is increasing. The objective was to evaluate the performance of 3 nonantibiotic topical treatments (salicylic acid and a compound of inorganic acids in a 20% solution and in a dry form) on DD in a commercial dairy herd. Within the 30-d test period, 42 DD lesions on 33 Holstein cows were assigned to receive 1 of the 3 treatments. Lesions were biopsied before and after treatment and were clinically evaluated 5 times. Improved lesions were clinically defined as either healed (regeneration of the skin) or healing (dry lesions covered by a scab). Unhealed lesions were defined as either active [with a raw, moist, strawberry-like (granulating) surface] or mature (with a raised papillomatous appearance). The effectiveness of treatment was evaluated histopathologically using the following scores: 0 (no spirochetes present), 1 (small number of spirochetes present in the epidermis), 2 (moderate number of spirochetes present and reaching an intermediary level in the epidermis), and 3 (large number of spirochetes present and reaching the deepest part of the epidermis or the superficial dermis). The improvement rate was 10/14 (71%) for salicylic acid, 11/15 (73%) for the inorganic acid solution, and 8/13 (62%) for the inorganic acid powder. The analysis showed no difference among treatments. The association between clinical score and histopathological score was determined by an odds ratio. The odds ratio of a healed lesion having spirochetes in the epidermis was 0.58 and that of an active DD lesion having spirochetes in the epidermis was 26.5.

Reactions of Three Lactones with Cl, OD, and O3: Atmospheric Impact and Trends in Furan Reactivity.

Lactones, cyclic esters of hydroxycarboxylic acids, are interesting biofuel candidates as they can be made from cellulosic biomass and have favorable physical and chemical properties for distribution and use. The reactions of γ-valerolactone (GVL), γ-crotonolactone (2(5H)-F), and α-methyl-γ-crotonolactone (3M-2(5H)-F) with Cl, OD, and O3 were investigated in a static chamber at 700 Torr and 298 ± 2 K. The relative rate method was used to determine kGVL+Cl = (4.56 ± 0.51) × 10-11, kGVL+OD = (2.94 ± 0.41) × 10-11, k2(5H)-F+Cl = (2.94 ± 0.41) × 10-11, k2(5H)-F+OD = (4.06 ± 0.073) × 10-12, k3M-2(5H)-F+Cl = (16.1 ± 1.8) × 10-11, and k3M-2(5H)-F+OD = (12.6 ± 0.52) × 10-12, all rate coefficients in units of cm3 molecule-1 s-1. An absolute rate method was used to determine k2(5H)-F+O3 = (6.73 ± 0.18) × 10-20 and k3M-2(5H)-F+O3 = (5.42 ± 1.23) × 10-19 in units of cm3 molecule-1 s-1. Products were identified for reactions of the lactones with Cl. In the presence of O2 the products are formic acid (HCOOH), formyl chloride (CHClO), and phosgene (CCl2O), and also maleic anhydride (C2H2(CO)2O) for 2(5H)-F. In addition both reactions produced a number of unidentified products that likely belong to molecules with the ring-structure intact. A review of literature data for reactions of other furans show that the reactivity of the lactones are generally lower compared to that of corresponding compounds without the carbonyl group.

Assumed non-persistent environmental chemicals in human adipose tissue; matrix stability and correlation with levels measured in urine and serum.

The aim of this study was to (1) optimize a method for the measurement of parabens and phenols in adipose tissue, (2) evaluate the stability of chemical residues in adipose tissue samples, and (3) study correlations of these compounds in urine, serum, and adipose tissue. Samples were obtained from adults undergoing trauma surgery. Nine phenols and seven parabens were determined by isotope diluted TurboFlow-LC-MS/MS. The analytical method showed good accuracy and precision. Limits of detection (LOD) for parabens and phenols ranged from 0.05 to 1.83ng/g tissue. Good recovery rates were found, even when biological samples remained defrosted up to 24h. Benzophenone-3 (BP-3; range of values: 70% of adipose tissue samples, while bisphenol-A (BPA; 40% of adipose tissue samples. In general, levels were similar between adipose tissue and serum, while a correlation between adipose tissue and urine was only found for BP-3. In conclusion, adipose tissue samples in this study were found to contain environmental chemicals considered to be non-persistent, whose levels were weakly or not at all correlated with the urine burden. Therefore, adipose tissue may potentially provide additional information to that obtained from other biological matrices. Further investigations are warranted to explore whether adipose tissue might be a suitable matrix for assessment of the consequences for human health of mid/long-term exposure to these chemicals.

Guidelines for time-to-event end point definitions in sarcomas and gastrointestinal stromal tumors (GIST) trials: results of the DATECAN initiative (Definition for the Assessment of Time-to-event Endpoints in CANcer trials)†.

BACKGROUND: The use of potential surrogate end points for overall survival, such as disease-free survival (DFS) or time-to-treatment failure (TTF) is increasingly common in randomized controlled trials (RCTs) in cancer. However, the definition of time-to-event (TTE) end points is rarely precise and lacks uniformity across trials. End point definition can impact trial results by affecting estimation of treatment effect and statistical power. The DATECAN initiative (Definition for the Assessment of Time-to-event End points in CANcer trials) aims to provide recommendations for definitions of TTE end points. We report guidelines for RCT in sarcomas and gastrointestinal stromal tumors (GIST). METHODS: We first carried out a literature review to identify TTE end points (primary or secondary) reported in publications of RCT. An international multidisciplinary panel of experts proposed recommendations for the definitions of these end points. Recommendations were developed through a validated consensus method formalizing the degree of agreement among experts. RESULTS: Recommended guidelines for the definition of TTE end points commonly used in RCT for sarcomas and GIST are provided for adjuvant and metastatic settings, including DFS, TTF, time to progression and others. CONCLUSION: Use of standardized definitions should facilitate comparison of trials' results, and improve the quality of trial design and reporting. These guidelines could be of particular interest to research scientists involved in the design, conduct, reporting or assessment of RCT such as investigators, statisticians, reviewers, editors or regulatory authorities.

Pentraxin-3 level at admission is a strong predictor of short-term mortality in a community-based hospital setting.

BACKGROUND: The pattern recognition molecule pentraxin-3 (PTX3) is a novel potential marker of prognosis, as elevated levels are associated with both disease severity and mortality in patients with a wide range of conditions. However, the usefulness of PTX3 as a prognostic biomarker in a general hospital setting is unknown. PATIENTS AND METHODS: The study cohort consisted of 1326 unselected, consecutive patients (age >40 years) admitted to a community hospital in Copenhagen, Denmark. Patients were followed until death or for a median of 11.5 years after admission. The main outcome measure was all-cause mortality. Serum samples collected from patients at admission and from 192 healthy control subjects were quantified for PTX3 level by enzyme-linked immunosorbent assay. RESULTS: PTX3 was elevated in patients (median 3.7 ng mL(-1) , range 0.5-209.8) compared with healthy nonhospitalized subjects (median 3.5 ng mL(-1) , range 0.0-8.3; P = 0.0003). Elevated PTX3 levels, defined as above the 95th percentile of the concentration in healthy subjects, were associated with increased overall mortality during the study (P < 0.0001). This increase in mortality was greatest in the short term, with an unadjusted hazard ratio (HR) of 6.4 [95% confidence interval (CI) 3.8-11.0] at 28 days after admission, compared to 1.7 (95% CI 1.4-2.0) at the end of follow-up. These results were still significant after adjustment for age, gender and glomerular filtration rate: adjusted HR of 5.0 (95% CI 2.9-8.8) and 1.4 (95% CI 1.2-1.8), respectively. CONCLUSION: These results suggest that PTX3 could be a widely applicable marker of short-term mortality in hospitalized patients and may be useful in the initial risk stratification.

Species-specific engagement of human nucleotide oligomerization domain 2 (NOD)2 and Toll-like receptor (TLR) signalling upon intracellular bacterial infection: role of Crohn's associated NOD2 gene variants.

Recognition of bacterial peptidoglycan-derived muramyl-dipeptide (MDP) by nucleotide oligomerization domain 2 (NOD2) induces crucial innate immune responses. Most bacteria carry the N-acetylated form of MDP (A-MDP) in their cell membranes, whereas N-glycolyl MDP (G-MDP) is typical for mycobacteria. Experimental murine studies have reported G-MDP to have a greater NOD2-stimulating capacity than A-MDP. As NOD2 polymorphisms are associated with Crohn's disease (CD), a link has been suggested between mycobacterial infections and CD. Thus, the aim was to investigate if NOD2 responses are dependent upon type of MDP and further to determine the role of NOD2 gene variants for the bacterial recognition in CD. The response pattern to A-MDP, G-MDP, Mycobacterium segmatis (expressing mainly G-MDP) and M. segmatisΔnamH (expressing A-MDP), Listeria monocytogenes (LM) (an A-MDP-containing bacteria) and M. avium paratuberculosis (MAP) (a G-MDP-containing bacteria associated with CD) was investigated in human peripheral blood mononuclear cells (PBMCs). A-MDP and M. segmatisΔnamH induced significantly higher tumour necrosis factor (TNF)-α protein levels in healthy wild-type NOD2 PBMCs compared with G-MDP and M. segmatis. NOD2 mutations resulted in a low tumour necrosis factor (TNF)-α protein secretion following stimulation with LM. Contrary to this, TNF-α levels were unchanged upon MAP stimulation regardless of NOD2 genotype and MAP solely activated NOD2- and Toll-like receptor (TLRs)-pathway with an enhanced production of interleukin (IL)-1ß and IL-10. In conclusion, the results indicate that CD-associated NOD2 deficiencies might affect the response towards a broader array of commensal and pathogenic bacteria expressing A-MDP, whereas they attenuate the role of mycobacteria in the pathogenesis of CD.

Hyponatraemia at hospital admission is a predictor of overall mortality.

BACKGROUND: Hyponatraemia is a prognostic marker of increased mortality and morbidity in selected groups of hospitalised patients. The aim of the present study was to examine the prevalence and prognostic significance of hyponatraemia at hospital admission in an unselected population with a broad spectrum of medical and surgical diagnoses. METHODS: Consecutive patients >40 years of age admitted to a general district hospital in Greater Copenhagen between 1 April 1998 and 31 March 1999. Median follow-up time was 5.16 years (range 0-4372 days). Plasma sodium measurements were available in 2960 patients, and hyponatraemia defined as P-Na(+) <137 mmol/L at hospital admission was present in 1105 (37.3 %) patients. RESULTS: One-year mortality was higher for hyponatraemic patients than for normonatraemic patients: 27.5% versus 17.7%. Moreover, hyponatraemia was an independent predictor of short and long-term all-cause mortality after 1 year and after the entire observation period respectively: hazard ratio (HR) 1.6 (95 % confidence interval (CI) 1.4-1.9, P < 0.0001) and HR 1.4 (95 % CI 1.3-1.6, P < 0.0001). Patients with hyponatraemia had longer hospitalisations than patients with normonatraemia: 7.6 (±0.38) days vs 5.6 (±0.21) days, P < 0.001. There was no interaction between hyponatraemia at admission and any admission diagnoses (P > 0.05 for all interaction analyses). CONCLUSION: Hyponatraemia is associated with increased all-cause mortality and longer admission length independently of diagnosis and clinical variables.

Assessment of the validity of a multigene analysis in the diagnostics of inflammatory bowel disease.

OBJECTIVES: The findings of a previous multigene study indicated that the expression of a panel of seven specific genes had strong differential power regarding inflammatory bowel disease (IBD) versus non-IBD, as well as ulcerative colitis (UC) versus Crohn's disease (CD). This prospective confirmatory study based on an independent patient cohort from a national Danish IBD centre was conducted in an attempt to verify these earlier observations. DESIGN, SETTING AND PARTICIPANTS: A total of 119 patients were included in the study (CD, UC and controls). Three mucosal biopsies were retrieved from the left side of the colon of each patient. RNA was extracted, and RT-PCR was performed to retain expression profiles from the seven selected genes. Expression data from the training set (18 CD, 20 UC and 20 controls) were used to build a classification model, using quadratic discriminant analysis, and data from the test set (20 CD, 21 UC and 20 controls) were used to test the validity of the model. RESULTS: The present investigation did not confirm the previous observation that a panel of seven specific genes is able to distinguish between patients with CD and UC, whereas the discriminative power for IBD versus control subjects was substantiated. CONCLUSION: Our results fail to demonstrate that the previously identified seven-gene classification model is able to discriminate between CD and UC but suggest that the gene panel merely discriminates between inflamed and noninflamed colonic tissue. Thus, a reliable and simple diagnostic tool is still warranted for optimal diagnosis and treatment of patients with IBD, especially the subgroup with unclassified disease.

Cardiovascular risk in patients with sleep apnoea with or without continuous positive airway pressure therapy: follow-up of 4.5 million Danish adults.

BACKGROUND: The prognostic significance of age and continuous positive airway pressure (CPAP) therapy on cardiovascular disease in patients with sleep apnoea has not been assessed previously. METHODS: Using nationwide databases, the entire Danish population was followed from 2000 until 2011. First-time sleep apnoea diagnoses and use of CPAP therapy were determined. Incidence rate ratios (IRRs) of ischaemic stroke and myocardial infarction (MI) were analysed using Poisson regression models. RESULTS: Amongst 4.5 million individuals included in the study, 33 274 developed sleep apnoea (mean age 53, 79% men) of whom 44% received persistent CPAP therapy. Median time to initiation of CPAP therapy was 88 days (interquartile range 34-346). Patients with sleep apnoea had more comorbidities compared to the general population. Crude rates of MI and ischaemic stroke were increased for sleep apnoea patients (5.4 and 3.6 events per 1000 person-years compared to 4.0 and 3.0 in the general population, respectively). Relative to the general population, risk of MI [IRR 1.71, 95% confidence interval (CI) 1.57-1.86] and ischaemic stroke (IRR 1.50, 95% CI 1.35-1.66) was significantly increased in patients with sleep apnoea, in particular in patients younger than 50 years (IRR 2.12, 95% CI 1.64-2.74 and IRR 2.34, 95% CI 1.77-3.10, respectively). Subsequent CPAP therapy was not associated with altered prognosis. CONCLUSIONS: Sleep apnoea is associated with increased risk of ischaemic stroke and MI, particularly in patients younger than 50 years of age. CPAP therapy was not associated with a reduced rate of stroke or MI.

SSX2-4 expression in early-stage non-small cell lung cancer.

The expression of cancer/testis antigens SSX2, SSX3, and SSX4 in non-small cell lung cancers (NSCLC) was examined, since they are considered promising targets for cancer immunotherapy due to their immunogenicity and testis-restricted normal tissue expression. We characterized three SSX antibodies and performed immunohistochemical staining of 25 different normal tissues and 143 NSCLCs. The antibodies differed in binding to two distinctive splice variants of SSX2 that exhibited different subcellular staining patterns, suggesting that the two splice variants display different functions. SSX2-4 expression was only detected in 5 of 143 early-stage NSCLCs, which is rare compared to other cancer/testis antigens (e.g. MAGE-A and GAGE). However, further studies are needed to determine whether SSX can be used as a prognostic or predictive biomarker in NSCLC.

Distinction among North Atlantic cod Gadus morhua stocks by tissue fatty acid profiles.

The fatty acid (FA) profiles of the white muscle and heart tissues of cod Gadus morhua from five locations, Faroe Bank, Faroe Plateau, North-West Iceland, Norway-Barents Sea and Denmark-Skagerrak, were population dependent. The interregional differences of FAs were significantly dissimilar (P < 0.01) in most cases. By way of a rapid and simple analytical method, the stock dependence and harvest location of individual G. morhua were chemometrically determined by multivariate principal component analysis. The difference among the stocks was correlated with the average water temperature at the harvest locations. It thus appears that the tissue FA profile is a phenotypic trait that is partly temperature driven.

Long-term exposure to traffic-related air pollution and diabetes-associated mortality: a cohort study.

AIMS/HYPOTHESIS: The aim of this study was to investigate whether air pollution from traffic at a residence is associated with mortality related to type 1 or type 2 diabetes. METHODS: We followed up 52,061 participants in the Danish Diet, Cancer and Health cohort for diabetes-related mortality in the nationwide Register of Causes of Death, from baseline in 1993-1997 up to the end of 2009, and traced their residential addresses since 1971 in the Central Population Registry. We used dispersion-modelled concentration of nitrogen dioxide (NO2) since 1971 and amount of traffic at the baseline residence as indicators of traffic-related air pollution and used Cox regression models to estimate mortality-rate ratios (MRRs) with adjustment for potential confounders. RESULTS: Mean levels of NO2 at the residence since 1971 were significantly associated with mortality from diabetes. Exposure above 19.4 µg/m³ (upper quartile) was associated with a MRR of 2.15 (95% CI 1.21, 3.83) when compared with below 13.6 µg/m³ (lower quartile), corresponding to an MRR of 1.31 (95% CI 0.98, 1.76) per 10 µg/m³ NO2 after adjustment for potential confounders. CONCLUSIONS/INTERPRETATION: This study suggests that traffic-related air pollution is associated with mortality from diabetes. If confirmed, reduction in population exposure to traffic-related air pollution could be an additional strategy against the global public health burden of diabetes.

The inflammatory biomarker YKL-40 at admission is a strong predictor of overall mortality.

OBJECTIVES: YKL-40 is an inflammatory biomarker associated with disease activity and mortality in patients with diseases characterized by inflammation and tissue remodelling. The aim of this study was to describe the prognostic value of YKL-40 in an unselected patient population. DESIGN: In consecutive patients admitted to hospital during a 1-year period, blood was collected and information regarding final diagnosis and mortality was collected. Median follow-up time was 11.5 years. SETTING: District hospital, Copenhagen, Denmark. PATIENTS: A total of 1407 patients >40 years of age were admitted acutely. MAIN OUTCOME MEASURE: All-cause mortality. RESULTS: Median YKL-40 was increased in patients (157 µg L(-1) , range 13-7704 µg L(-1) ) compared to healthy controls (40 µg L(-1) , range 29-58 µg L(-1) ; P < 0.001). Patients with YKL-40 in the highest quartile had a hazard ratio (HR) of 7.1 [95% confidence interval (CI) 4.2-12.0] for all-cause mortality in the first year and 3.4 (95% CI 2.8-4.2) in the total study period, compared to those in the lowest quartile (HR = 1). The HR for death for all patients with YKL-40 above the normal age-corrected 95th percentile was 2.1 (95% CI 1.6-2.7) after 1 year and 1.5 (95% CI 1.3-1.7) during the total study period, compared to patients with YKL-40 below the age-corrected 95th percentile. The results of multivariable analysis showed that YKL-40 was an independent biomarker of mortality; this was most significant in the first year. YKL-40 was a marker of prognosis in all disease categories. The HR for death was increased in patients with YKL-40 above the normal age-corrected 95th percentile in healthy subjects independent of type of disease (all P < 0.001). CONCLUSION: The level of YKL-40 at admission is a strong predictor of overall mortality, independent of diagnosis and could be useful as a biomarker in the acute evaluation of all patients.

Detection of porcine circovirus type 2 and viral replication by in situ hybridization in primary lymphoid organs from naturally and experimentally infected pigs.

Porcine circovirus type 2 (PCV2) infection is the cause of postweaning multisystemic wasting syndrome (PMWS). It has been speculated whether cell types permissive of replication are found in the primary lymphoid organs and whether infection of these tissues has an important role in the pathogenesis of PMWS. The aim of this study was to determine if primary lymphoid organ cells support viral replication during PCV2 infection. This was done by histopathological examination of thymus and bone marrow from pigs experimentally inoculated with PCV2 (n = 24), mock-infected pigs (n = 12), pigs naturally affected by PMWS (n = 33), and age-matched healthy control animals (n = 29). In situ hybridization (ISH) techniques were used to detect PCV2 nucleic acid irrespective of replicative status (complementary probe, CP) or to detect only the replicative form of the virus (replicative form probe, RFP). PCV2 was not detected in the experimentally PCV2-inoculated pigs or the control animals. Among the PMWS-affected pigs, 19 of 20 (95%) thymuses were positive for PCV2 by CP ISH, and 7 of 19 (37%) of these also supported viral replication. By CP ISH, PCV2 was detected in 16 of 33 (48%) bone marrow samples, and 5 of 16 (31%) of these also supported replication. The 2 ISH probes labeled the same cell types, which were histiocytes in both organs and lymphocytes in thymus. The RFP labeled fewer cells than the CP. Thus, PCV2 nucleic acids and replication were found in bone marrow and thymus of PMWS-affected pigs, but there was no evidence that primary lymphoid organ cells are major supporters of PCV2 replication.

Effects of a 17q21 chromosome gene variant, tobacco smoke and furred pets on infant wheeze.

The first common genetic factor identified for pediatric asthma by genome-wide association is the chromosome 17q21 locus, harbouring the ORMDL3 gene. ORMDL3 is involved in facilitation of endoplasmic reticulum-mediated inflammatory responses, believed to underlie its asthma association. We investigated associations between the rs7216389 polymorphism in the 17q21 locus affecting ORMDL3 expression and the risk for recurrent wheeze and interactions with exposure to tobacco smoke and furred pets during pregnancy and infancy using a birth cohort of 101,042 infants. Rs7216389 was significantly associated with recurrent wheeze risk among 18-month-old infants. There was a 1.35-fold higher risk of recurrent wheeze among homozygous variant allele carriers compared with homozygous wild-type allele carriers. There was significant interaction between rs7216389 and domestic furred pets, with a positive association between pets and wheeze among homozygous wild-type carriers and a negative association among homozygous variant allele carriers. There was no interaction between rs7216389 and tobacco smoke exposure.

Corn ethanol production, food exports, and indirect land use change.

The approximately 100 million tonne per year increase in the use of corn to produce ethanol in the U.S. over the past 10 years, and projections of greater future use, have raised concerns that reduced exports of corn (and other agricultural products) and higher commodity prices would lead to land-use changes and, consequently, negative environmental impacts in other countries. The concerns have been driven by agricultural and trade models, which project that large-scale corn ethanol production leads to substantial decreases in food exports, increases in food prices, and greater deforestation globally. Over the past decade, the increased use of corn for ethanol has been largely matched by the increased corn harvest attributable mainly to increased yields. U.S. exports of corn, wheat, soybeans, pork, chicken, and beef either increased or remained unchanged. Exports of distillers' dry grains (DDG, a coproduct of ethanol production and a valuable animal feed) increased by more than an order of magnitude to 9 million tonnes in 2010. Increased biofuel production may lead to intensification (higher yields) and extensification (more land) of agricultural activities. Intensification and extensification have opposite impacts on land use change. We highlight the lack of information concerning the magnitude of intensification effects and the associated large uncertainties in assessments of the indirect land use change associated with corn ethanol.

Atmospheric chemistry of t-CF3CH=CHCl: products and mechanisms of the gas-phase reactions with chlorine atoms and hydroxyl radicals.

FTIR-smog chamber techniques were used to study the products and mechanisms of the Cl atom and OH radical initiated oxidation of trans-3,3,3-trifluoro-1-chloro-propene, t-CF(3)CH=CHCl, in 700 Torr of air or N(2)/O(2) diluent at 296 ± 2 K. The reactions of Cl atoms and OH radicals with t-CF(3)CH=CHCl occur via addition to the >C=C< double bond; chlorine atoms add 15 ± 5% at the terminal carbon and 85 ± 5% at the central carbon, OH radicals add approximately 40% at the terminal carbon and 60% at the central carbon. The major products in the Cl atom initiated oxidation of t-CF(3)CH=CHCl were CF(3)CHClCHO and CF(3)C(O)CHCl(2), minor products were CF(3)CHO, HCOCl and CF(3)COCl. The yields of CF(3)C(O)CHCl(2), CF(3)CHClCOCl and CF(3)COCl increased at the expense of CF(3)CHO, HCOCl and CF(3)CHClCHO as the O(2) partial pressure was increased over the range 10-700 Torr. Chemical activation plays a significant role in the fate of CF(3)CH(O)CHCl(2) and CF(3)CClHCHClO radicals. In addition to reaction with O(2) to yield CF(3)COCl and HO(2) the major competing fate of CF(3)CHClO is Cl elimination to give CF(3)CHO (not C-C bond scission as previously thought). As part of this study k(Cl + CF(3)C(O)CHCl(2)) = (2.3 ± 0.3) × 10(-14) and k(Cl + CF(3)CHClCHO) = (7.5 ± 2.0) × 10(-12) cm(3) molecule(-1) s(-1) were determined using relative rate techniques. Reaction with OH radicals is the major atmospheric sink for t-CF(3)CH=CHCl. Chlorine atom elimination giving the enol CF(3)CH=CHOH appears to be the sole atmospheric fate of the CF(3)CHCHClOH radicals. The yield of CF(3)COOH in the atmospheric oxidation of t-CF(3)CH=CHCl will be negligible (<2%). The results are discussed with respect to the atmospheric chemistry and environmental impact of t-CF(3)CH=CHCl.

The impact of Staphylococcus aureus concentration on the development of pulmonary lesions and cytokine expression after intravenous inoculation of pigs.

Acute respiratory distress syndrome is a common complication in severe sepsis. In pigs, the lungs play an important role in clearing systemic bacterial infections due to pulmonary intravascular macrophages found specifically in pigs. However, this increases the exposure of the porcine lungs to pathogens and potential injury. The authors propose that increasing the concentration of the inoculum without changing the bacterial dose will lead to severe sepsis with pronounced pulmonary lesions. This could potentially create a risk of cytokine spillover to the circulation, leading to an increased systemic response. Eight Danish Landrace pigs, approximately 10 weeks old, were inoculated twice with a low or once with a high concentration of Staphylococcus aureus. Three pigs were sham-inoculated. The animals were grouped based on macro- and microscopic lung lesions. The mRNA expression of local pulmonary inflammatory markers was compared to protein levels of systemic inflammatory markers. The most severe pulmonary lesions were observed in animals receiving the high S. aureus concentration, indicating that severity of lesions is dependent on inoculum concentration rather than total numbers of bacteria. Furthermore, local mRNA expression of inflammatory cytokines appeared to be dependent on the magnitude and severity of tissue destruction, including the ability to confine the lesions. Increasing mRNA levels of serum amyloid A could be a confident marker of severity of pulmonary lesions. Since no correlation was observed between local and systemic levels of inflammatory cytokines, this finding could indicate an ability of the porcine lung to compartmentalize the local inflammatory response and thus restrict systemic contribution.