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Competing Interests: Competing interests The authors declare no competing interests.

The preterm neonatal airway epithelium is constantly exposed to environmental stressors. One of these stressors in neonates with lung disease includes oxygen (O2) tension higher than the ambient atmosphere - termed hyperoxia (>21% O2). The effect of hyperoxia on the airway depends on various factors, including the developmental stage of the airway, the degree of hyperoxia, and the duration of exposure, with variable exposures potentially leading to unique phenotypes. While there has been extensive research on the effect of hyperoxia on neonatal lung alveolarization and airway hyperreactivity, little is known about the short and long-term underlying effect of hyperoxia on human neonatal airway epithelial cells. A major reason for this is the scarcity of an effective in vitro model to study human neonatal airway epithelial development and function. Here, we describe a method for isolating and expanding human neonatal tracheal airway epithelial cells (nTAECs) utilizing human neonatal tracheal aspirates and culturing these cells in air-liquid interface (ALI) culture. We demonstrate that nTAECs form a mature polarized cell-monolayer in ALI culture and undergo mucociliary differentiation. We also present a method for moderate hyperoxia exposure of the cell monolayer in ALI culture using a specialized incubator. Additionally, we describe an assay to measure cellular oxidative stress following hyperoxia exposure in ALI culture using fluorescent quantification, which confirms that moderate hyperoxia exposure induces cellular oxidative stress but does not cause significant cell membrane damage or apoptosis. This model can potentially be used to simulate clinically relevant hyperoxia exposure encountered by neonatal airways in the Neonatal Intensive Care Unit (NICU) and used to study the short and long-lasting effects of O2 on neonatal airway epithelial programming. Studies using this model could be utilized to explore ways to mitigate early-life oxidative injury to developing airways, which is implicated in the development of long-term airway diseases in former premature infants.

Background: Body dysmorphic disorder consists of excessive concern with minimal appearance defects, which causes functional impairment. Its prevalence is estimated to range from 5% to 35% of dermatological patients, especially adult women with esthetic complaints., Objectives: To investigate the prevalence and factors associated with dysmorphic disorder in female dermatological patients, in a public institution in Brazil., Methods: This was a cross-sectional study involving adult women attended at a public dermatological service in Brazil. Participants underwent a demographic survey, in addition to a screening form for body dysmorphic disorder (Body Dysmorphic Disorder Examination [BDDE]). The presence of dysmorphic disorder (BDDE > 66 points) was assessed among the participants according to demographic covariates and psychological problems, through logistic regression., Results: A total of 223 women were evaluated. The BDDE showed high internal consistency (Cronbach's α = 0.90). It is noteworthy the high prevalence of psychological problems and the fact that over one-third (38%) of the sample presented a high degree of dissatisfaction with their image. The prevalence of dysmorphic disorder was 48% among women with esthetic complaints and 30% among the others (p < 0.01). Lower family income (OR = 2.97), history of domestic violence (OR = 3.23), search for dermatological care due to an esthetic complaint (OR = 2.05), and suicidal ideation (OR = 4.22) were independently associated with the occurrence of body dysmorphic disorder., Study Limitations: This was a single-center study of a non-randomized sample from public service., Conclusions: Body dysmorphic disorder is prevalent among female dermatological patients; it is associated with traumatic psychological experiences, lower income, affective disorders, and demand for esthetic care. It is essential to recognize the diagnosis in order to treat such patients and refer them for appropriate psychiatric treatment instead of trying to satisfy their esthetic demands., (Copyright © 2021 Sociedade Brasileira de Dermatologia. Published by Elsevier España, S.L.U. All rights reserved.)

Brucella spp. and Leptospira spp. antibodies were surveyed in 35 southern elephant seals (SESs) Mirounga leonina at Elephant Island (South Shetland Islands), western Antarctic peninsula, in the Austral summer of 2003 and 2004. The rose Bengal test and a commercial competitive ELISA (c-ELISA) were used to detect Brucella spp. exposure, and the microscopic agglutination test (MAT) with 22 live serovars was used to determine anti-Leptospira spp. antibodies. We found evidence of Brucella spp. exposure in 3 of 35 (8.6%) SESs tested via the c-ELISA displaying high percentage inhibition (PI), similar to other studies in pinnipeds in which Brucella spp. antibodies have been determined. Two of the 3 positives were pups (PI = 70.4 and 86.6%), while the third was an adult female (PI = 48.8%). The 3 c-ELISA positive SESs were additionally tested via the serum agglutination test but were found to be negative. All individuals were negative for antibodies against 22 Leptospira spp. serovars by MAT. These results contribute to the knowledge and monitoring of zoonotic pathogens with epizootic potential in Southern Ocean pinnipeds. Given the potential impact that pathogens may have on the abundance of wild (sometimes threatened and endangered) populations, constant monitoring and surveillance are required to prevent pathogen spread, particularly under forecast climate change scenarios.

The field of simulation and optimisation of dynamic mixing elements ('mixers') is lacking good methods for spatially resolved validation and flow visualisation. For this reason, the authors present an experimental setup that gives better insight into the thermal, distributive and dispersive mixing process by measuring melt temperatures upstream of the mixer and injecting a secondary, visually distinguishable stream of melt upstream. Running extrusion trials for a polyethylene on both a rhomboidal and a Maddock mixer, temperatures, gray scale distribution of images of extrudates and size of dispersed domains in incompatible polystyrene were measured. It was found that temperatures upstream and downstream of the mixer can be quantified. This was used to validate a simulation of thermal mixing. In distributive mixing, good agreement with simulation and an excellent spatial resolution were observed, thereby identifying an area of the rhomboidal mixer in need of geometric improvement. For dispersive mixing, a trend coherent with extrusion theory was found.

Spontaneous spinal epidural haematoma is a rare condition with serious long- term effects. It has no proven causes but is associated with use of blood thinners, coagulopathies, underlying vascular malformations or tumours, and pregnancy. This is a case report of a 57-year-old woman with an atypical presentation, where an intracranial condition was suspected. The case is presented to increase awareness of the condition as a differential diagnosis, when stroke or subarachnoid haemorrhage is ruled out, and how important it is to refer these patients to an acute spinal MRI to avoid further neurological deterioration.

Cardiogenic shock (CS) refractory to conventional therapies continues to be a challenging medical syndrome, with poor prognosis and high complication and mortality rates. The application and use of temporary mechanical circulatory support (MCS) is a component in the treatment of CS patients and should be applied early in the presentation. Crucial to the success of their application, temporary MCS devices should be chosen based on degree of patient acuity and etiology of CS. Not all temporary MCS devices deliver the same degree of hemodynamic support and range from minimal support to systemic support via veno-arterial extracorporeal membrane oxygenation., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Reptiles are the unique ectothermic amniotes, providing the key link between ectothermic anamniotes fish and amphibians, and endothermic birds and mammals; becoming an important group to study with the aim of providing significant knowledge into the evolutionary history of vertebrate immunity. Classification systems for reptiles' leukocytes have been described by their appearance rather than function, being still inconsistent. With the advent of modern techniques and the establishment of analytical protocols for snakes' blood by flow cytometry, we bring a qualitative and quantitative assessment of innate activities presented by snakes' peripheral blood leukocytes, thereby linking flow cytometric features with fluorescent and light microscopy images. Moreover, since corticosterone is an important immunomodulator in reptiles, hormone levels of all blood samples were measured. We provide novel and additional information which should contribute to better understanding of the development of the immune system of reptiles and vertebrates., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Agitation is frequent in the acute psychiatric setting. The observation and treatment of agitation is important to avoid harm to patients or staff, to reduce distress of the patient, and to reduce the risk of coercion, especially physical restraint., Aim: To evaluate the effect of intramuscular treatment with psychotropics on agitation in a non-selected acute psychiatric population., Methods: The Positive and Negative Syndrome Scale Excitement Component (PANSS-EC) was implemented in the acute psychiatric ward at Psychiatric Center Copenhagen to improve assessment and treatment of agitation. During a period of almost ~2 years the staff was requested to assess agitation before and after administration of intramuscular injections., Results: PANSS-EC was obtained at baseline and within 2 hours after injection for 135 injections with antipsychotics or benzodiazepines administered to 101 acute, non-selected psychiatric patients with high occurrence of co-morbid substance abuse. Mean PANSS-EC at baseline was 26.53 ± 4.87, and mean reduction in PANSS-EC was 14.99 ± 8.48 (p < 0.001). For 73% of injections PANSS-EC decreased with ≥40% (generally accepted definition of response). In 49% of cases patients were subjected to physical restraint. Patients subjected to restraint had a significantly higher PANSS-EC score. Patients who received a subsequent injection had a significantly lower decline in PANSS-EC score. Besides two cases of acute dystonia following haloperidol injections, no serious side-effects were observed., Conclusions: Treatment of agitation with intramuscular injections of psychotropics was in general effective in this non-selected, highly agitated psychiatric population, and injections were well tolerated.

Inter-α-trypsin inhibitor heavy chain 5 (ITIH5) is supposed to be involved in extracellular matrix stability and thus may play a key role in the inhibition of tumor progression. The current study is the first to analyze in depth ITIH5 expression and DNA methylation, as well as its potential clinical impact in non-small-cell lung carcinoma (NSCLC). We examined ITIH5 mRNA expression in tumor and adjacent normal lung tissue specimens of NSCLC patients. In addition, methylation frequency of the ITIH5 promoter was investigated using methylation-specific PCR and pyrosequencing. Significance of our data was validated by independent data sets from The Cancer Genome Atlas and the Kaplan-Meier Plotter platform. Furthermore, ITIH5 protein expression was evaluated by immunohistochemistry utilizing a tissue microarray with 385 distinct lung tissue samples. Based on our tissue collections, ITIH5 mRNA expression was significantly decreased in NSCLC compared to normal lung tissue in line with an increased methylation frequency in lung cancer tissue. Independent TCGA data confirmed significant expression loss of ITIH5 in lung cancer concordant with ITIH5 promoter hypermethylation in NSCLC. Of interest, low ITIH5 mRNA expression was particularly found in the magnoid and squamoid ADC expression subtype, concordant with an unfavorable patients' outcome in squamoid as well as tobacco smoking ADC patients. In conclusion, ITIH5 may be a novel putative tumor suppressor gene in NSCLC with a potential molecular significance in the squamoid ADC subtype and further clinical impact for risk stratification of adenocarcinoma patients. In addition, ITIH5 may serve as a novel biomarker for prognosis of tobacco smoking ADC patients.

Objective: Speech inconsistency is characterised by variable productions of the same lexical items within the same context. This study aimed to describe inconsistencies among Brazilian Portuguese (BP)-speaking children with and without phonological disorder (PD) as well as the effectiveness of a speech inconsistency test (SIT)., Methods: The study sample included children between 5 years 0 months (5;0 years) and 10;10 years of age, both genders, 51 children with PD and 50 without speech-language disorders. The SIT includes 25 pictures, each named 3 times in different sequences within the same session., Results: The inconsistency average of children with PD (27.4%) was higher than that of typically developing children (9.8%). Linear regression showed age and gender effects, receiver operating characteristic curves were built for speech inconsistency with combined gender and age cutoff values. Inconsistent subjects among typically developing children included 2 younger boys and 2 older girls. Inconsistencies were found among children with PD, including 10 boys up to 7;6 years and 11 over this age, and 7 girls up to 7;6 years and 6 over this age., Conclusion: Speech inconsistency in BP-speaking children seems to be an effective measure for differentiating children with PD from those with typically developing phonology., (Copyright © 2011 S. Karger AG, Basel.)

Objective: Stimulability is the ability to produce an adequate sound under specific conditions. This study aimed to describe the stimulability of Brazilian Portuguese-speaking children with and without phonological disorders for the production of liquid sounds with the aid of visual and tactile cues., Patients and Methods: The study sample included 36 children between 5;0 and 11;6 years of age, 18 with phonological disorder and 18 without any speech-language disorders. Stimulability was measured for syllable imitation. The stimulability test employed includes 63 syllables with the sounds [i], [lh], and [r], as well as seven oral vowels. If the subject was unable to imitate a sound, a visual cue was given. When necessary, a tactile cue was also given., Results: The sound [lh] required greater use of sensory cues. Children with phonological disorder needed a greater number of cues., Conclusion: The use of sensory cues seemed to facilitate sound stimulability, making it possible for the children with phonological disorder to accurately produce the sounds modeled.

Objectives: To determine the correlation between the protein/creatinine ratio and 24-h proteinuria; to estimate the sensitivity and specificity of this ratio for the diagnosis of significant proteinuria; to establish its cutoff point with the best predictive value for the diagnosis of significant proteinuria in patients with systemic arterial hypertension., Study Design: A cross-sectional study of 47 hypertensive patients who had been pregnant for 20 weeks or more seen at the Maternity of the University Hospital of Porto Alegre. The studied factor was the protein/creatinine ratio measured in a single random urine sample and the outcome was protein determination in 24-h urine. The level of significance was set at 0.05., Results: The correlation coefficient between the protein/creatinine ratio and 24-h proteinuria was 0.94 when urine was properly collected. A receiver-operator characteristic curve was constructed to determine the sensitivity and specificity of the ratio for the diagnosis of significant proteinuria (> or = 300 mg in 24 h). Specificity and predictive positive value were 100% for a ratio > or = 0.8. The best values for sensitivity, specificity, positive predictive value, and negative predictive value in the diagnosis of proteinuria > or = 300 mg in 24 h were obtained when the protein/creatinine ratio was 0.5 (0.96, 0.96, 0.96, and 0.96, respectively)., Conclusion: The protein/creatinine ratio measured in a single urine sample taken at random from hypertensive pregnant women showed good sensitivity and specificity for the diagnosis of 24-h proteinuria > or = 300 mg and was strongly correlated with 24-h proteinuria. A ratio of 0.5 mg/mg is predictive of significant proteinuria and can be used for the diagnosis and follow-up of hypertensive pregnant women.

We investigated differences in maternal plasma and trophoblast prostaglandin metabolism associated with preterm births. Tissue prostaglandins (PGs) E2 and F2 alpha and the stable plasma PGF2 alpha metabolite, 13,14-dihydro-15-keto-PGF2 alpha, were measured in preterm (< 37 weeks) and term (< or = 37 weeks) births. Amnion PGE2 in preterm (106.1 +/- 15.7 ng/g wet weight tissue; x +/- SEM; n = 37) was lower than in term (176.6 +/- 22.7 ng/g wet weight; x +/- SEM; n = 34, P < 0.02). Placenta PGE2 was lower in preterm (34.7 +/- 19.7 ng/g wet weight; x +/- SEM) than in term (103.3 +/- 28.0 ng/g wet weight; x +/- SEM, P < 0.04). Preterm PGF2 alpha was consistently lower in the amnion (106.8 +/- 17.5 ng/g wet weight) and placenta (102.5 +/- 8.7 ng/g wet weight) than in term amnion (188.2 +/- 24.8 ng/g wet weight; P < 0.01) and placenta (128.9 +/- 7.8 ng/g wet weight; P < 0.03). Chorionic PGE2 and plasma PGF2 alpha metabolite followed this trend but did not reach significance. These findings suggest qualitative and quantitative differences in maternal and trophoblast eicosanoid metabolism between term and preterm parturition.

Recent advances in instrumentation and methodologies are redefining the study of lipid nutrition by allowing probing for subtle responses to marginal variations in nutrients. Stable isotope labeling studies allow demonstration of chain elongation, desaturation, chain shortening and resynthesis in humans. Essential fatty acid deficiency affects membrane physicochemical properties and membrane-bound protein activity. Understanding of the molecular functions of dietary fat has progressed to conceptualization of complex competing and complementary interactions and signals. The physical properties of lipids--insolubility in water and amphipathic qualities--underlie their physiological function. These findings will lead to new biomarkers of health status.

Platelet thromboxane (TX) production was examined in response to dietary copper. Groups of eight rats were fed copper-deficient, -marginal, and -adequate diets providing 0.5, 1.7, and 7.5 micrograms Cu/g, respectively, with controlled dietary Se and vitamin E. Platelets were purified and washed by centrifugation. Separate platelet samples from each rat were challenged with 10 micrograms/ml of collagen and 1 unit/ml (27.3 nM) of thrombin in Tyrode's buffer, 2.0 mM Ca2+. Platelet copper-dependent superoxide dismutase (CuSOD) activity showed a significant depression with reduced diet copper, but platelet glutathione peroxidase activity was unaffected. Challenged platelet TX production showed a significant 1.5- to 2.5-fold increase in response to both dietary copper deficiency and marginality, with highly significant negative correlations between challenged platelet TX production and platelet CuSOD activity and between TX production and copper status (liver copper). Endogenous (unchallenged) platelet lipid hydroperoxide concentrations, measured as free fatty acid hydroperoxides by a glutathione-disulfide-specific glutathione reductase recycling assay, showed a nonsignificant 47-67% increase in copper deficiency. Pooled data showed a significant 71% increase in platelet lipid hydroperoxides in copper deficiency. Platelet TX production showed a significant correlation with endogenous lipid hydroperoxides. The results suggest that dietary copper insufficiency increases platelet TX synthesis through changes in CuSOD in a dose-responsive (diet copper and platelet CuSOD activity) manner, and that platelet TX synthesis is influenced by lipid hydroperoxides (peroxide tone).

Agonist challenged aortic prostacyclin production was examined in copper-adequate, -marginal and -deficient rats fed AIN-based diets providing 6.7, 1.7 and 0.8 micrograms Cu/g, respectively. Aortic rings were incubated in Krebs-Henseleit salts, 10 mmol/L HEPES buffer, pH 7.4, 95%:5% O2:CO2, 37 degrees C, and equilibrated for 1 h. Equilibrated rings were challenged with buffer (basal), 273.0 nmol/L thrombin and angiotensin II at 84.6 pmol/L and 846.0 pmol/L. Prostacyclin production, determined at 10 minutes by RIA as 6-keto prostaglandin F1 alpha, in basal and 84.6 pmol/L angiotensin II ring incubations was significantly reduced by 28 to 48% in copper-deficient rats. With thrombin or 846.0 pmol/L angiotensin II prostacyclin production was significantly reduced by 18 to 55% in copper-marginal and copper-deficient rats. Copper-dependent superoxide dismutase activity was significantly depressed by 30 and 57% in aortae of copper-marginal and copper-deficient rats. Lipid peroxidation, estimated by the thiobarbituric acid test, was significantly increased by 85% in copper-deficient rats, with a nonsignificant 40% increase in aortae from copper-marginal rats. The results suggest that the decreases in aortic prostacyclin production in aortae from both copper-deficient and copper-marginal rats are associated, in a dose-dependent manner, with copper-dependent superoxide dismutase depression and increases in aortic lipid peroxidation.

The aim of this study was to determine how plasma fatty acids (FA) of subjects eating either a diet designed to match the US diet consumed in 1974 in fat content and composition in accord with the HANES I survey (US74) or a diet modified to meet the US Dietary Goal Recommendations (MOD) are altered, and how the changes affect platelet thromboxane (TXB2) synthesis, and prostacyclin (PGI2) and prostaglandin E2 (PGE2) synthesis by cultured human endothelial cells. Following a period of recorded self-selected diets, 10 women ate the US74 diet for 4 weeks, changing to the MOD diet for the next 4 weeks (sequence 1), and 10 ate the MOD diet followed by the US74 diet (sequence 2). Plasma triglycerides, free FA, platelet FA composition, and red blood cell phospholipids responded to the change from self-selected to controlled diets, but differences in responses were not seen between US74 and MOD diets. Red blood cell total FA did not respond to dietary changes. Under collagen but not thrombin stimulation, platelet TXB2 synthesis was correlated with platelet arachidonate concentration but not serum cholesterol. Endothelial cells were isolated from umbilical cord veins and incubated for 72 hours with a 20% medium of the women's plasma. In sequence 1 (high saturated FA to high polyunsaturated fatty acids), but not in 2 (reverse order), plasma from subjects eating the MOD diet decreased (p less than 0.05) basal and thrombin-stimulated PGI2 and PGE2 synthesis by the cells. These cells had a higher content of linoleic acid than cells from subjects eating the US74 diet. Thus, our study suggests that an increase in the intake of linoleic acid from 4.8 to 7.6 en% decreases PGI2 and PGE2 synthesis by human endothelial cells, and supplementation of the diet with linoleic acid has a longer period of effectiveness than its decrease in the diet.

Platelet thromboxane synthesis in response to supplemental linoleate in the diet has been very inconsistent. The objective of this study was to investigate potential confounding factors known to affect platelet thromboxane synthesis. Citrated whole blood was recalcified with varying Ca2+ concentrations and challenged with low or high dose collagen preparations to induce extreme ranges of thromboxane synthesis from endogenous arachidonate pools by rat platelets. Male and female weanling rats were fed 0.0, 1.0 or 23 energy percent linoleate for 11 to 13 weeks. Fasting tended to enhance thromboxane synthesis. Both fasted and fed females showed slightly faster rates of thromboxane synthesis than males. Essential fatty acid deficiency depressed (P less than 0.01) thromboxane synthesis; the degree of this depression was inversely related to the level of recalcification (68% for 0.0 mM Ca2+, 36% for 2.5 mM Ca2+ and 20% for 5.0 mM Ca2+) when challenged with the high dose collagen. Essential fatty acid deficiency depressed platelet phospholipid arachidonate concentration 26%. Only blood from fed females stimulated with a mild challenge responded to excess dietary linoleate, and a 62% (not statistically significant) depression in TX synthesis was observed and this was associated with a decrease in platelet phospholipid arachidonate concentration.

Leukotrienes constrict smooth muscle and could be important for the regulation of the pulmonary circulation. We examined the production and action of lipoxygenase metabolites in isolated lungs, where we controlled the perfusing fluid used. Arachidonate injected into isolated rat lungs perfused with cell- and protein-free physiological salt solution caused a transient pressor response. Following indomethacin, arachidonate caused a delayed slow pressure rise followed by edema. The lung effluent contracted the guinea pig ileum. High-pressure liquid chromatography (HPLC) analysis of the perfusate demonstrated the presence of leukotrienes (LTC4 and LTD4). Diethylcarbamazine, a leukotriene synthesis inhibitor, prevented the slow pressure rise and edema seen after indomethacin plus arachidonate. In lungs perfused with cell- and protein-free physiological salt solution, LTC4, but not LTD4, caused a transient pressure rise followed by a sustained pressure rise. The sustained rise was abolished by a leukotriene-receptor blocker (FPL 55712) but not by indomethacin. In blood-perfused lungs, LTC4 caused only the transient pressure rise that was not blocked by FPL 55712. In lungs perfused with physiological salt solution containing albumin, LTC4 had no effect. We concluded that 1) perfused nonsensitized rat lungs produced LTC4 and LTD4; 2) LTC4 may be a major pulmonary vasoconstrictor; and 3) albumin binding limits the pressor effect of LTC4.

It is known that reactive oxygen species cause lung injury in association with activation of arachidonate metabolism. Because metabolites of the cyclooxygenase pathway do not appear to mediate the injury, we considered that the 5-lipoxygenase pathway might be activated and that inhibition of the pathway could interfere with the development of the injury. Thus, we sought to induce an oxidant lung injury and to prevent such injury by inhibiting lipoxygenase pathway or by blocking leukotriene action. In isolated rat lungs, glucose oxidase added to a glucose-containing, cell-free perfusate was used to produce the injurious oxygen species. Lung edema occurred and increased with increasing oxygen tension in the inspired air. Light microscopy of the lung showed perivascular fluid cuffs, and electron microscopy showed endothelial cell damage. Measurements in the lung effluent showed that concentrations of 5-hydroxyeicosatetraenoic acid (5-HETE) and of cyclooxygenase metabolites increased after glucose oxidase administration; BW 755C, U60,257, and FPL 55712 inhibited the glucose-oxidase-induced lung edema. And U60,257 also inhibited the glucose-oxidase-induced increase in 5-HETE without concomitant inhibition of cyclooxygenase metabolites. Thus, glucose oxidase via generation of active oxygen species stimulated the lung 5-lipoxygenase pathway, and inhibitors of 5-lipoxygenase protected against the oxidant lung injury. Further, in these experiments, the injury occurred in the absence of circulating blood cells and was augmented by increasing the inspired oxygen concentration.

Chronic hyperoxia produces pathological changes in lung which can be fatal. With an interest in delineating dietary factors which might affect the pulmonary response to hyperoxia, we fed rats a semi-synthetic diet containing polyunsaturated fatty acids (PUFA) as either 5% or 78% of the fat complement. The rats were exposed to pure oxygen at one atmosphere. Half the animals in each diet group were injected with aspirin during the hyperoxic exposure. Radioimmunoassay of lung prostaglandins (PG) F2alpha, E2 and E1 were performed at 0, 24, 48 and 72 hours. The major findings were: (1) Feeding the high PUFA diet elevated lung PG synthetic potential tenfold over that of low PUFA-fed animals. There was no effect of diet on mortality. (2) Hyperoxia significantly increased F2alpha-synthetic potential during the first 24 hours of hyperoxia and moderately increased the synthetic potential of E2 and E1. (3) Aspirin significantly depressed synthetic potential of all three PG prior to oxygen exposure but its effect was overcome during hyperoxia. Aspirin-injected rats showed 80% mortality in oxygen vs. 50% for saline controls.

Active oxygen species can cause lung injury. Although a direct action on endothelial cells is proposed, the possibility exists that they might cause injury via mediators. We considered that active oxygen species would stimulate the generation of cyclooxygenase metabolites, which then alter pulmonary vasoreactivity and cause edema. We chemically produced hydrogen peroxide by adding glucose oxidase to a plasma- and cell-free, but beta-D-glucose-containing, solution, which perfused isolated rat lungs. Addition of glucose oxidase to the perfusate caused a marked decrease in pulmonary vasoreactivity, accompanied by an increase in the concentrations of prostacyclin, thromboxane A2, and prostaglandin F2 alpha. Pretreatment with catalase, a specific scavenger of hydrogen peroxide, preserved pulmonary vasoreactivity, inhibited the increase of the concentration of the measured prostaglandins, and prevented edema formation. Indomethacin effectively blocked lung prostaglandin production but neither prevented the decrease in vasoreactivity nor inhibited edema formation. From these data we conclude that hydrogen peroxide impaired pulmonary vasoreactivity and subsequently caused edema. Despite the fact that hydrogen peroxide stimulated lung prostaglandin production, cyclooxygenase-derived products neither caused the decrease in vasoreactivity nor the development of edema.

Reactive oxygen metabolites cause pulmonary vasoconstriction and activate arachidonic acid metabolism. We proposed that hydrogen peroxide, generated enzymatically in an insolated rat lung model, would cause vasoconstriction which was independent of circulating cells, but dependent on activation of the arachidonic acid cascade. Although hydrogen peroxide caused an increase in lung effluent thromboxane B2 concentration, indomethacin did not inhibit hydrogen peroxide induced vasoconstriction. In order to test the hypothesis that hydrogen peroxide activates the 5-lipoxygenase pathway, lung effluents were analyzed for 5-hydroxy-eicosatetranoic acid (5-HETE) using a sensitive, highly specific mass spectrometer technique. Glucose oxidase increased the 5-HEFE effluent concentrations and this was prevented by U60,257. We therefore conclude that hydrogen peroxide stimulates the 5-lipoxygenase pathway and that substances derived from this pathway are at least in part responsible for the hydrogen peroxide induced vasoconstriction in isolated rat lungs.

Evidence that biosynthesis of prostaglandins (PG) in tissues of animals deficient in essential fatty acids is dependent on the availability of their precursors has been demonstrated. The purpose of this study was to determine the following: (1) effects of dietary linoleate enrichment on PG biosynthesis in rats; (2) effects of exogenous PGE2 and dietary linoleate on plasma free fatty acids and serum cholesterol in fed and fasted rats. Rats were fed three different concentrations of dietary linoleate as beef tallow, hydrogenated vegetable fat, or corn oil. The concentrations of PGE1 and PGF2a measured by radioimmunoassay were higher in rats fed the fed the beef tallow diet independent of energy status. A decrease in the concentration of PG between fasted and fed rats receiving hydrogenated vegetable fat is discussed in respect to the possible influence of trans isomers of unsaturated fatty acids on the biosynthesis of PG. There were significant effects of fasting on serum cholesterol concentration regardless of diet and significant interactions among effects of PGE2, fasting, and diet, suggesting regulatory effects of PGE2 on serum cholesterol concentration. The increase in plasma free fatty acids associated with fasting was prevented by PGE2 for all diets, but had the most marked effect on rats fed hydrogenated vegetable fat.

The influence of dietary fat on prostaglandin production and lipolysis was tested in basal and norepinephrine stimulated adipocytes isolated from the epididymal fat pads of fasted rats. Seven diets varying in fat calories and polyunsaturation were utilized. No basal differences were noted for prostaglandin E2 production or lipolysis. Norepinephrine stimulated prostaglandin E2 and F2alpha production was significantly (P less than 0.01) increased with greater polyunsaturation of fat, but not by increased fat calories. Norepinephrine stimulated lipolysis was depressed by an increase in fat calories but was unaffected by the degree of polyunsaturation of fat. This is in vitro evidence against the concept that prostaglandins play a feedback regulator role in fat cell lipolysis since no correlation could be made between the two parameters.

Essential fatty acid deficiency consistently depresses eicosanoid (prostaglandin E2, F2, and I2 and thromboxane) biosynthesis independent of sampling protocols. Tissue fatty acid analyses support the hypothesis that the decrease is due in part to depression of arachidonate and accumulation of eicosatrienoate (n-9). Research on the alteration of eicosanoid biosynthesis by dietary linoleate supplementation is reviewed extensively. Responses of whole blood, lung, liver and heart eicosanoid synthesis to feeding eight concentrations of dietary linoleate between 0 and 27 energy percent are reported. It is concluded that stimulation, depression and no change in eicosanoid production could be equally well documented as a response to linoleate supplementation. Evidence for the obvious mechanism that alterations in precursor fatty acid composition are a possible explanation is fragmentary and inconsistent. The appropriate sampling techniques appear not to be established at this time and most likely are species, gender and tissue specific.

The effects of dietary linoleate as zero to 27% of energy, fed to female rats for 6 months, in relation to ability of whole blood to synthesize PG during clotting at 37 degrees was studied. Synthesis of PGE1, PGE2, PGF2 apha and TXB2 after 10 or 40 minutes of incubation of whole blood was determined by assay of serum concentration by radioimmunoassay. Fatty acid composition of serum phospholipids, cholesteryl esters and acyl glycerides was determined. PG synthesis increased with linoleate as zero to 2% of kcal; from 2% up to 7% there was a decrease of PG synthesis; from 7% to 27% there was a linear increase. There was no pattern to PGF2 alpha maximum concentration. PGE2 had a linear increase from 0 to 30% linoleate. PGE1 decreased with 0 to 2% linoleate, then increased between 2 and 7% and maintained a plateau through 27%. The concentration of TXB2 was found to be about 20-40 times that of PGE2 and PGF2 alpha. The decline of PGE1 synthesis with 2-7% linoleate calories was correlated with 20:3n-6 concentration and PGE2 and PGF2 alpha production with 20:4. With dietary linoleate concentrations greater than 7.4% PG synthesis had a linear increase up to 27% of kilocalories, not correlated with fatty acids.

Prostaglandin synthesis shows dependence on lipid hydroperoxides and resultant oxygen derived radical formation. In view of the importance of dietary copper in cytosolic copper dependent superoxide dismutase (Cu/Zn SOD) activity and the role of SOD in oxygen radical formation, the influence of dietary copper on prostacylin (PGI2) synthesis and SOD activity in rat aorta was examined. Copper deficient (0.5 micrograms Cu/g diet) rats showed a significant 47% reduction in PGI2 synthesis rates by aortic ring incubations in comparison to copper adequate (6.0 micrograms Cu/g diet) animals. Aortic SOD activity was reduced by 46% in copper deficiency in comparison to copper adequate animals. Marginal dietary copper (1.6 micrograms Cu/g diet) significantly reduced aortic SOD activity by 32% but was without effect on aortic ring incubation PGI2 synthesis. These results indicate that dietary copper deficiency, and the resultant decrease in SOD activity, depresses aortic PGI2 synthesis.

Hepatocytes isolated from female rats meal-fed a high-glucose diet were incubated in Krebs-Henseleit bicarbonate medium containing 16.5 mM glucose, 3H2O, and 14C-labeled amino acids (-)-Hydroxycitrate depressed the incorporation of 3H2O and [14C] alanine into fatty acids and cholesterol. Incorporation of [U-14C]leucine into lipids was not affected but incorporation of 3H2O into lipids was decreased significantly by (-)-hydroxycitrate. (-)-Hydroxycitrate depressed the incorporation of radioactivity from [2-14C]leucine into fatty acids and cholesterol by 61 and 38%, respectively, and stimulated the incorporation of radioactivity from [4,5-3H]leucine 35 and 28%. As [2-14C]leucine labels the acetyl-CoA pool and [4,5-3H]leucine labels the acetoacetate pool, it was concluded that mitochondrial 3-hydroxy-3-methylglutaryl-CoA is not incorporated intact into cholesterol, and that acetoacetate can be activated effectively in the liver cytosol for support of cholesterol and fatty acid synthesis.

Weanling male rats were fed a semi-purified diet containing 10, 20, 40 or 60% of calories as fat having a constant polyunsaturated/saturated fatty acid ratio of 0.7. After 21-28 d of feeding, animals from each treatment group were exposed to pure oxygen at one atmosphere absolute for up to 72 h. Some animals were sacrificed after 0 or 48 h of oxygen exposure and lung tissue analyzed for the activities of the hexose monophosphate shunt and prostaglandin dehydrogenase/reductase. Other animals were exposed to hyperoxia until death. With increasing dietary fat content, the pre-exposure activities of the two enzymes decreased and oxygen-induced mortality increased. There was no dietary effect on enzyme activities after 48 h of hyperoxia. We concluded that both dietary fat content and the pre-exposure activity of prostaglandin dehydrogenase/reductase influenced the relative susceptibility to pulmonary oxygen poisoning.

Weanling male rats were fed semi-purified diets supplemented with 0, 60, or 600 IU X g-1 vitamin E or 0, 100 or 1000 ppb selenium. One group was injected daily with vitamin E at a rate equivalent to consumption of 60 IU X kg-1. Animals from all groups were sacrificed after exposure to normobaric oxygen or air for 48 h. Lung tissue was analyzed for the combined activity of prostaglandin dehydrogenase and reductase. Using the decline in enzyme activity as an indicator of susceptibility to oxygen poisoning, protection against hyperoxia was directly related to the level of vitamin E supplementation. Selenium supplemented at 100 ppb provided significant protection when compared to 0 ppb or 1000 ppb. The latter dose may have been marginally toxic. We conclude that dietary supplementation of vitamin E and selenium may influence the relative susceptibility of an animal to pulmonary oxygen poisoning.

We tested the hypothesis that monocrotaline would activate arachidonic acid metabolism in rats. If activation occurred before the pulmonary hypertension developed, arachidonate metabolites could play a role in the hypertensive monocrotaline injury. We found that 1 wk after monocrotaline administration 6-ketoprostaglandin F1 alpha and leukotriene C4 were increased in lung lavages. At 3 wk when pulmonary hypertension was well developed, lung lavage contained increased 6-ketoprostaglandin F1 alpha and thromboxane B2. In addition, the number and activity of white blood cells in the lavages was increased, and abnormal alveolar macrophages were present. The lung extract contained slow-reacting substances including leukotriene D4. Indomethacin administration inhibited the formation of cyclooxygenase metabolites but did not prevent pulmonary hypertension. Diethylcarbamazine administration reduced the numbers and activity of inflammatory cells, increased pulmonary hypertension, prevented right ventricular hypertrophy, and inhibited the formation of slow-reacting substances. We concluded that arachidonate metabolism was activated before pulmonary hypertension developed, that the inflammatory cells in the alveolus accompanied the hypertensive process, and that diethylcarbamazine attenuated both the monocrotaline-induced inflammatory response and the pulmonary hypertension.

Diets supplying 20 or 40% of the calories as fat with linoleate to saturated fatty acid ratios of 0.4, 0.8 and 5.5 were fed to male weanling rats for 8 and 11 weeks. Recalcification clotting time was not affected by dietary treatment. Concentration of cAMP in the platelets was significantly elevated at the highest level of dietary linoleate. Cyclic AMP was negatively correlated with concentration of dihomo-gamma-linolenic acid in platelet phospholipids and positively correlated with prostaglandin E1, suggesting that dihomo-gamma-linolenic acid is rapidly converted to prostaglandin E1 causing a rise of cAMP due to stimulation of adenylate cyclase. Dietary treatment did not markedly change the composition of the platelet phospholipid fatty acids and, therefore, resulted in no change in synthesis of the proaggregatory prostaglandin by platelets during clotting. Although the fatty acid composition of the platelet phospholipids remained constant, dietary treatment did affect the total amount of phospholipid fatty acid present in the platelet. Serum concentrations of cholesterol were significantly higher in rats fed the 20% fat diet than in rats fed the 40% fat diet. Platelet cholesterol followed the same trend as serum cholesterol indicating that the cholesterol content of platelets appears to reflect the lipid environment of the plasma.

The direct and indirect evidence that the fatty acid composition of dietary fat is involved in the regulation of prostaglandin biosynthesis was reviewed. Direct evidence included effects of essential fatty acid deficiencies and excesses on endogenous tissue levels and production rates of prostaglandins by several tissues. Indirect evidence included lipolytic, platelet aggregatory, hypertensive, inflammatory and immune responses. In general, composition of dietary fat did not affect prostaglandin biosynthesis unless a biochemical essential fatty acid deficiency was induced or the linoleate to saturated fatty acids ratio of the dietary fat was greater than 5. Most results were interpreted in light of changing fatty acid composition; however, very few direct measurements have been made.

Prostaglandin metabolism by rat lung tissue was measured following exposures of 6, 24 and 48 hours to either pure oxygen or air at one atmosphere. Tissue concentrations of PGE1, PGE2 and PGF2 alpha were not altered by oxygen exposures. Prostaglandin synthetase activity decreased between 24 and 48 hours but was not significantly different from control at 48 hours. Combined prostaglandin dehydrogenase/reductase activity decreased between 24 and 48 hours to 13% of control values and was significantly lower than in air at 48 hours. The plasma concentration of 13, 14 dihydro-15-keto PGF2 alpha, a catabolite of PGF2 alpha, was significantly lower in oxygen-exposed rats at 24 and 48 hours. We conclude that endogenous pulmonary prostaglandin concentrations are maintained during hyperoxia but that catabolism of prostaglandins by the lungs may be impaired.

Acetylcholine causes pulmonary vasodilation, but its mechanism of action is unclear. We hypothesized that acetylcholine-induced pulmonary vasodilation might be associated with prostacyclin formation. Therefore, we used isolated rat lungs perfused with a recirculating cell- and plasma-free physiological salt solution to study the effect of acetylcholine infusion on pulmonary perfusion pressure, vascular responsiveness and lung prostacyclin production. Acetylcholine (20 micrograms infused over 1 minute) caused immediate vasodilation during ongoing hypoxic vasoconstriction and prolonged depression of subsequent hypoxic and angiotensin II-induced vasoconstrictions. Both effects of acetylcholine were abolished by atropine pretreatment. The prolonged acetylcholine effect, but not the immediate response, was blocked by meclofenamate, an inhibitor of cyclooxygenase. The prolonged effect, but not the immediate response, of acetylcholine was associated with an increase in perfusate 6-keto-PGF1 alpha concentration. The acetylcholine stimulated increase in 6-keto-PGF1 alpha production was inhibited by meclofenamate and by atropine. Thus, blockade of prostacyclin production corresponded with blockade of the prolonged acetylcholine effect. In conclusion, acetylcholine caused in isolated rat lungs an immediate vasodilation and a prolonged, time-dependent depression of vascular responsiveness. Whereas both acetylcholine effects were under muscarinic receptor control, only the prolonged effect depended on the cyclooxygenase pathway and, presumably, prostacyclin synthesis.

The hypothesis was tested that vitamin E protects chickens from a lethal Escherichia coli infection by inhibiting the biosynthesis of prostaglandins, thereby activating humoral immunity and phagocytosis. When chickens were fed supplement vitamin E at the level of 300 mg/kg diet, which is six times the presently used dietary level, endogenous PGE1, PGE2, and PGF2 alpha levels decreased in the immunopoietic organs, bursa, and spleen. Antibody titers to E. coli lipopolysaccharide and phagocytosis increased at the same time. Infection slightly increased prostaglandin levels and vitamin E appeared to compensate for this increase. Aspirin, a known prostaglandin inhibitor acted synergistically with vitamin E in depressing endogenous PG levels in bursa and decreasing mortality from E. coli infection.

Because deformation of lung tissue stimulates prostaglandin synthesis, we wanted to investigate whether hydrodynamic forces would affect lung prostacyclin (PGI2) production. To test the hypothesis that lung prostacyclin synthesis was flow dependent, we examined lung prostacyclin production after flow alterations. Using a salt solution that contained either Ficoll or albumin as a perfusate, we changed the flow to half and to double the control flow. When flow was changed, lung prostacyclin production followed changes in flow and pressure drop. When flow was varied in lungs treated with indomethacin, prostacyclin production was too low to be measurable. Variations in pressure pulsatility at constant mean flow had no influence on lung prostacyclin production. Since vascular distension may also stimulate prostacyclin production, we increased venous pressure. An increase in venous pressure (from 2.1 to 4.8 mmHg) had no effect on prostacyclin production; a further increase in venous pressure (to 7.5 mmHg) initiated edema and caused a large increase in prostacyclin production. When we subjected monolayers of endothelial cells cultured in wells to defined shear rates, the prostacyclin concentration in the supernatant quickly increased to a maximum. The absence of further increase with greater shear may have reflected feedback control of prostacyclin synthesis. The results indicated that hydrodynamic disturbances affect endothelial cells and stimulate arachidonate metabolism. Lung prostacyclin production may be related to flow. However, this effect is small compared with the lung prostacyclin production during edema formation.

The effects of fasting and dietary linoleate on eicosanoid production in clotting rat blood incubated 10 minutes at 37 degrees C was studied. Fasting increased eicosanoid synthesis. Dietary manipulation of eicosanoid levels was best demonstrated in the fed rat model. TXB2, PGE2, F2 alpha, and E1 synthesis increased when dietary linoleate increased from 0.0 to 0.4% calories; from 0.4 to 29% linoleate calories there was no change in PG synthesis, but a decrease in TXB2 production was apparent.

A review of research in the authors' laboratories regarding effects of dietary fat polyunsaturation upon longevity in rats and some aspects of the regulation of cholesterol metabolism with regard to age of rats and humans is presented. The longevity of the rat was found to be enhanced by consumption of dietary fat providing a polyunsaturated to saturated fatty acid (P/S) ratio of 0.3 to 1, corresponding to about 5-12% of energy (en%) as linoleate, compared with less or more polyunsaturated fat. Mechanisms of the effects of the fats upon cholesterol metabolism were studied. With advancing age, there seems to be a decline in the rate of catabolism of cholesterol, resulting in longer retention in the body of the rat. In the human, there seems to be a decline in regulation of uptake of cholesterol by leukocytes and, therefore, perhaps other tissues, resulting in increased synthesis of cholesterol by the peripheral tissues. Moderate rather than high dietary consumption of polyunsaturated fat seems to be favorable to metabolic processes contributing to longevity.