Longitudinal associations between post-traumatic stress disorder and metabolic syndrome severity.

BACKGROUND: Post-traumatic stress disorder (PTSD) is associated with elevated risk for metabolic syndrome (MetS). However, the direction of this association is not yet established, as most prior studies employed cross-sectional designs. The primary goal of this study was to evaluate bidirectional associations between PTSD and MetS using a longitudinal design. METHOD: A total of 1355 male and female veterans of the conflicts in Iraq and Afghanistan underwent PTSD diagnostic assessments and their biometric profiles pertaining to MetS were extracted from the electronic medical record at two time points (spanning ~2.5 years, n = 971 at time 2). RESULTS: The prevalence of MetS among veterans with PTSD was just under 40% at both time points and was significantly greater than that for veterans without PTSD; the prevalence of MetS among those with PTSD was also elevated relative to age-matched population estimates. Cross-lagged panel models revealed that PTSD severity predicted subsequent increases in MetS severity (ß = 0.08, p = 0.002), after controlling for initial MetS severity, but MetS did not predict later PTSD symptoms. Logistic regression results suggested that for every 10 PTSD symptoms endorsed at time 1, the odds of a subsequent MetS diagnosis increased by 56%. CONCLUSIONS: Results highlight the substantial cardiometabolic concerns of young veterans with PTSD and raise the possibility that PTSD may predispose individuals to accelerated aging, in part, manifested clinically as MetS. This demonstrates the need to identify those with PTSD at greatest risk for MetS and to develop interventions that improve both conditions.

Cotton dust, endotoxin and cancer mortality among the Shanghai textile workers cohort: a 30-year analysis.

BACKGROUND: Although occupational exposure to cotton dust and endotoxin is associated with adverse respiratory health, associations with cancer are unclear. We investigated cancer mortality in relation to cotton dust and endotoxin exposure in the Shanghai textile workers cohort. METHODS: We followed 444 cotton textile and a reference group of 467 unexposed silk workers for 30 years (26 777 person-years). HRs for all cancers combined (with and without lung cancer) and gastrointestinal cancer were estimated in Cox regression models as functions of cotton textile work and categories of cumulative exposure (low, medium, high), after adjustment for covariates including pack-years smoked. Different lag years accounted for disease latency. RESULTS: Risks of mortality from gastrointestinal cancers and all cancers combined, with the exclusion of lung cancer, were increased in cotton workers relative to silk workers. When stratified by category of cumulative cotton exposure, in general, risks were greatest for 20-year lagged medium exposure (all cancers HR=2.7 (95% CI 1.4 to 5.2); cancer excluding lung cancer HR=3.4 (1.7-7.0); gastrointestinal cancer HR=4.1 (1.8-9.7)). With the exclusion of lung cancer, risks of cancer were more pronounced. When stratified by category of cumulative endotoxin exposure, consistent associations were not observed for all cancers combined. However, excluding lung cancer, medium endotoxin exposure was associated with all cancers and gastrointestinal cancer in almost all lag models. CONCLUSIONS: Cotton dust may be associated with cancer mortality, especially gastrointestinal cancer, and endotoxin may play a causative role. Findings also indirectly support a protective effect of endotoxin on lung cancer.

Associations and relative risks of pulmonary hypertension and lung diseases in individuals with methamphetamine use disorder.

OBJECTIVE: Methamphetamine causes considerable short- and long-term adverse health effects. Our aim was to assess the effects of methamphetamine use on pulmonary hypertension and lung diseases at the population level. METHODS: This population-based retrospective study used data from the Taiwan National Health Insurance Research Database between 2000 and 2018 that included 18,118 individuals with methamphetamine use disorder (MUD) and 90,590 matched participants of the same age and sex without substance use disorder as the non-exposed group. A conditional logistic regression model was used to estimate associations of methamphetamine use with pulmonary hypertension and lung diseases such as lung abscess, empyema, pneumonia, emphysema, pleurisy, pneumothorax, or pulmonary hemorrhage. Incidence rate ratios (IRRs) of pulmonary hypertension and hospitalization due to lung diseases were determined between the methamphetamine group and non-methamphetamine group using negative binomial regression models. RESULTS: During an 8-year observation period, 32 (0.2%) individuals with MUD and 66 (0.1%) non-methamphetamine participants suffered from pulmonary hypertension, and 2652 (14.6%) individuals with MUD and 6157 (6.8%) non-methamphetamine participants suffered from lung diseases. After adjusting for demographic characteristics and comorbidities, individuals with MUD were 1.78 times (95% confidence interval (CI) = 1.07-2.95) more likely to have pulmonary hypertension and 1.98 times (95% CI = 1.88-2.08) more likely to have a lung disease, especially emphysema, lung abscess, and pneumonia in descending order. Furthermore, compared to the non-methamphetamine group, the methamphetamine group was associated with higher risks of hospitalization caused by pulmonary hypertension and lung diseases. The respective IRRs were 2.79 and 1.67. Individuals with polysubstance use disorder were associated with higher risks of empyema, lung abscess, and pneumonia compared to individuals with MUD alone, with respective adjusted odds ratios of 2.96, 2.21, and 1.67. However, pulmonary hypertension and emphysema did not differ significantly between MUD individuals with or without polysubstance use disorder. CONCLUSIONS: Individuals with MUD were associated with higher risks of pulmonary hypertension and lung diseases. Clinicians need to ensure that a methamphetamine exposure history is obtained as part of the workup for these pulmonary diseases and provide timely management for this contributing factor.

Circulating adhesion molecules after short-term exposure to particulate matter among welders.

BACKGROUND: Studies from several countries indicate that welders experience increased risk of mortality and morbidity from ischaemic heart disease. Although the underlying mechanisms are unclear, vascular responses to particulate matter contained in welding fumes may play a role. To investigate this, we studied the acute effects of welding fume exposure on the endothelial component of vascular function, as measured by circulating adhesion molecules involved in leukocyte adhesion (sICAM-1 and sVCAM-1) and coagulation (vWF). METHODS: A panel of 26 male welders was studied repeatedly across a 6 h work-shift on a high exposure welding day and/or a low exposure non-welding day. Personal PM(2.5) exposure was measured throughout the work-shift. Blood samples were collected in the morning (baseline) prior to the exposure period, immediately after the exposure period, and the following morning. To account for the repeated measurements, we used linear mixed models to evaluate the effects of welding (binary) and PM(2.5) (continuous) exposure on each blood marker, adjusting for baseline blood marker concentration, smoking, age and time of day. RESULTS: Welding and PM(2.5) exposure were significantly associated with a decrease in sVCAM-1 in the afternoon and the following morning and an increase in vWF in the afternoon. CONCLUSIONS: The data suggest that welding and short-term occupational exposure to PM(2.5) may acutely affect the endothelial component of vascular function.

Continuous and online analysis of heart rate variability.

Spectral analysis of heart rate variability provides a probe to assess the function of the sympathetic and parasympathetic nervous systems. Time-frequency analysis of heart rate variability is useful for investigating autonomic nervous function in patients with syncope or non-sustained ventricular tachycardia, or in anaesthesia, etc. In this paper, we developed an algorithm for continuous and online analysis of heart rate variability. The algorithm was simulated and evaluated in MATLAB, and implemented on the digital signal processor. The electrocardiogram signals from MIT/BIH arrhythmia database and one patient with syncope demonstrate the capability of the proposed method in the continuous and online analysis of heart rate variability.

Role of striatal dopamine in delayed neurotoxic effects of organophosphorus compounds.

Mipafox administered to rats daily for 35 days produced ataxia and a reduction in the level of dopamine in the corpus striatum. Treatment with Leptophos for the same period produced slight motor dysfunction and a small but significant reduction in the level of striatal dopamine. Fenitrothion neither produced motor dysfunction nor changed the level of striatal dopamine. The cholinesterase activity of corpus striatum was inhibited by all the compounds. The results suggest the possible involvement of striatal dopamine in the delayed neurotoxic effects of certain organophosphorus compounds.

The effects of Penicillium roqueforti toxin on the activity of rat hepatic DNA polymerases.

PR toxin, a mycotoxin from cultures of Penicillium roqueforti, inhibited the in vitro activities of rat liver DNA polymerase alpha, beta, and gamma irrespectively of the nature of template-primer used. The concentration required for 50% inhibition of DNA polymerase alpha was 5-6 X 10(-6) M, while those for DNA polymerase beta and gamma were several times higher. By using DNA polymerase beta as a model, and based on the enzyme and template-primer concentration effects and also from the kinetic analysis on PR toxin inhibition, we concluded that two action mechanisms of PR toxin inhibition on in vitro DNA synthesis are operative. Inhibition of the in vitro DNA synthesis directed by DNA template was mediated primarily through alteration of the enzyme itself, whereas in the DNA synthesis reaction directed by RNA template DNA primer, the impairment of template or primer function due to PR toxin treatment probably had occurred. The inhibition of DNA polymerase by PR toxin persisted even after exhaustive dialysis. Addition of PR toxin to an ongoing reaction also inhibited DNA synthesis. Inactivation of DNA polymerase activity of PR toxin likely involved some essential amino acid residues other than sulfhydryl groups.

Influence of dietary selenite on the binding characteristics of rat serum proteins to mercurial compounds.

The effect of dietary selenite on the binding characteristics of serum proteins was investigated with rats. In the control serum, the maximal binding of phenylmercuric acetate (PMA) and methylmercuric chloride (MMC) to rat serum protein was approx. 18 and 9 nmoles per mg protein, respectively. The binding of Hg2+ was biphasic and it did not reach a maximum at the concentrations used. Selenite treatment caused a reduction in binding capacity of serum proteins to Hg2+ and PMA, and an increase in the binding affinities. However, there were no such changes for the binding of MMC. Selenite protection from mercury toxicity, therefore, acts not only via a change in tissue distribution and a change in the formation of seleno-proteins but, also, via a change in the binding characteristics to some mercury compounds. In the case of methylmercury, a different mechanism of protection must exist as the modification of tissue distribution, its binding to subcellular and soluble proteins and the binding characteristics remained equivocal.

Studies on the synthesis of some xanthonoid derivatives possessing antiplatelet effects.

2,3- and 3,4-Dihydroxyxanthone react with ethyl 2,3-dibromopropanoate to form the new, substituted 1,4-benzodioxanes 3 and 4, respectively. The regioisomers 3a and 3b; 4a and 4b were separated by column chromatography and characterized for evaluation of the antiplatelet effects in rabbit washed platelets and human platelet-rich plasma. The ethoxycarbonyl derivatives 3a (20 microM) and 3b (20 microM) strongly inhibited the aggregation of rabbit washed platelets induced by arachidonic acid and collagen. The compound 4b showed the most potent inhibition of rabbit washed-platelet aggregation induced by arachidonic acid (IC50 = 8.3 microM). Of the compounds tested in human platelet-rich plasma, compound 4b exhibited the most potent inhibition of primary and secondary aggregation induced by adrenaline (IC50 = 8.6 microM). We conclude that the antiplatelet effects of these four ethoxycarbonyl derivatives are mainly due to an inhibitory effect on thromboxane formation and interference in the adrenaline-receptor interaction.

Neurocomputing with time delay analysis for solving convex quadratic programming problems.

This paper presents a neural-network computational scheme with time-delay consideration for solving convex quadratic programming problems. Based on some known results, a delay margin is explicitly determined for the stability of the neural dynamics, under which the states of the neural network does not oscillate. The configuration of the proposed neural network is provided. Operational characteristics of the neural network are demonstrated via numerical examples.

Heartbeat detection using energy thresholding and template match.

Heartbeat detection is very important for retrieving the vital signs of heart functions. The morphologies and inter-beat intervals of heartbeats can reveal the condition of heart contraction. In this paper, we developed a heartbeat information integration scheme to deal with the information yielded by the energy thresholding and template match methods, which are usually used to detect the heartbeats and match the QRS, respectively. The proposed method are developed in SIMULINK 2.0 and assessed by the MIT/BIH arrhythmia database. The result demonstrated excellent sensitivity of detecting QRS and ventricular premature contraction in the proposed method.

Studies on the sorption of elemental mercury vapor by soils.

Mercury vapor sorption by soil increased curvilinearly with the increase of soil moisture content until a maximum was reached. A further increase of moisture content caused a decline in mercury sorption. The percent moisture contents which gave maximal increase of 203Hg vapor sorption in these soils coincide quite closely with their water-holding capacity values at 1/3 bar. Soil microorganisms may play a part in moist soil for the increase of elemental mercury vapor sorption and subsequent transformation to mercuric form. Mercury vapor diffused into both dry and moist soil columns and the diffusion profile can be described by an exponential function of the form, y = ae-bx, where "a" is the adsorption characteristics of the soil, "b" is the diffusivity coefficient and x is the depth of soil. The diffusivity coefficient for mercury vapor varied with the soil type and its moisture content.

In vitro binding of 14C-labeled acidic compounds to serum albumin and their tissue distribution in the rat.

The acidic compounds, such as phenoxyacetic acids, substituted benzoic acids, or acetylsalicylic acid, were found to bind to bovine serum albumin (BSA). Among phenoxyacetic acids, the binding affinity to BSA was highest for 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), which was approximately 4-, 24-, and 160-fold greater than those for 2,4-dichlorophenoxyacetic acid (2,4-D), o-chlorophenoxyacetic acid (CPA), and phenoxyacetic acid (PAA), respectively. There were two bound to serum albumins of other mammalian species. The binding affinity varied among species and also depended on the chemicals. However, the order of binding affinity in the albumin of each species remained the same as observed in BSA with few exceptions. Blood/tissue ratios of 14C from rats dosed with these 14C-labeled acids were highly correlated with the logarithm of the binding affinity constantsaffinity constants.

Estimation of whole-plant resistance to gaseous exchange independent of leaf temperature measurement.

For studies into the uptake of mercury vapor by wheat (Triticum aestivum), a simple theory and plant chamber were employed to estimate total leaf resistance of whole plants to water vapor exchange. The estimates were independent of leaf temperature, for which mean values were indirectly determined. The approach involved the measurement, at steady-state conditions, of the net change in water vapor flux per unit of leaf surface (Deltaq(v)) in response to a small induced change in absolute humidity (DeltaC(a)). Assuming that total leaf resistance (r(l)) was constant and that change in leaf temperature (T(l)) was negligible, total leaf resistance was calculated from the equation, [Formula: see text]While the assumptions concerning r(l) and T(l) may or may not be correct, evidence is presented which indicates that such assumptions did not significantly alter estimates of r(l) from their true values for changes in ambient relative humidity ranging from 0.011 to 0.074. Total leaf resistance of groups of whole plants estimated in this manner did not differ for ambient temperatures of 17, 25, and 33 C. Mean values of r(l) ranged from 83 sec cm(-1) in darkness to 2.4 sec cm(-1) at an illumination of 12.8 klux.

Uptake of mercury vapor by wheat: an assimilation model.

Using a whole-plant chamber and (203)Hg-labeled mercury, a quantitative study was made of the effect of environmental parameters on the uptake, by wheat (Triticum aestivum), of metallic mercury vapor, an atmospheric pollutant. Factors were examined in relation to their influence on components of the gas-assimilation model, [Formula: see text]where U(Hg) is the rate of mercury uptake per unit leaf surface, C(a)' is the ambient mercury vapor concentration, C(l)' is the mercury concentration at immobilization sites within the plant (assumed to be zero), r(l.Hg) is the total leaf resistance to mercury vapor exchange, and r(m.hg) is a residual term to account for unexplained physical and biochemical resistances to mercury vapor uptake.Essentially all mercury vapor uptake was confined to the leaves. r(l.hg) was particularly influenced by illumination (0 to 12.8 klux), but unaffected by ambient temperature (17 to 33 C) and mercury vapor concentration (0 to 40 mug m(-3)). The principal limitation to mercury vapor uptake was r(m.hg), which was linearly related to leaf temperature, but unaffected by mercury vapor concentration and illumination, except for apparent high values in darkness.Knowing C(a)' and estimating r(l.hg) and r(m.hg) from experimental data, mercury vapor uptake by wheat in light was accurately predicted for several durations of exposure using the above model.

Differential uptake of mercury vapor by gramineous c(3) and c(4) plants.

The uptake of mercury vapor by six gramineous plant species was compared under uniform conditions using a whole-plant chamber and (203)Hg-labeled mercury at a low atmospheric concentration. Mean Hg uptake by leaves of the C(3) species oats (Avena sativa), barley (Hordeum vulgare), and wheat (Triticum aestivum) was 5 times greater than that by leaves of the C(4) species corn (Zea mays), sorghum (Sorghum bicolor), and crabgrass (Digitaria sanguinalis). Although there was a difference in resistances associated with vapor entry into the leaves, as shown by estimates of gas exchange, the differential uptake by C(3) and C(4) species was largely attributable to internal resistances to Hg vapor binding. The nature of the internal resistances and the site or sites of Hg vapor binding remain unspecified.

The binding of various mercurial compounds to serum proteins.

Binding study of 203Hg-labeled Hg2+, PMA, MMC and EMC tp serum albumin of six mammalian species, bovine hemoglobin and bovine lambda-globulin is presented. Both MMC and EMC bound only weakly to serum albumin and lambda-globulin and more strongly to hemoglobin; Hg2+ bound very strongly to both albumin and hemoglobin and weakly to lambda-globulin; and PMA bound most strongly to albumin, next to hemoglobin and the least, to lambda-globulin. The available binding sites varied from one to five per molecule of protein. Human serum albumin has the lowest association constants with all four mercurial compounds, indicating that it was not as tightly bound to mercurial compounds as found with serum albumins from other species.