Prioritized neural processing of social threats during perceptual decision-making.

Emotional signals, notably those signaling threat, benefit from prioritized processing in the human brain. Yet, it remains unclear whether perceptual decisions about the emotional, threat-related aspects of stimuli involve specific or similar neural computations compared to decisions about their non-threatening/non-emotional components. We developed a novel behavioral paradigm in which participants performed two different detection tasks (emotion vs. color) on the same, two-dimensional visual stimuli. First, electroencephalographic (EEG) activity in a cluster of central electrodes reflected the amount of perceptual evidence around 100 ms following stimulus onset, when the decision concerned emotion, not color. Second, participants' choice could be predicted earlier for emotion (240 ms) than for color (380 ms) by the mu (10 Hz) rhythm, which reflects motor preparation. Taken together, these findings indicate that perceptual decisions about threat-signaling dimensions of facial displays are associated with prioritized neural coding in action-related brain regions, supporting the motivational value of socially relevant signals.

Efficacy of a Carrageenan gel Against Transmission of Cervical HPV (CATCH): interim analysis of a randomized, double-blind, placebo-controlled, phase 2B trial.

OBJECTIVES: To evaluate the efficacy of a carrageenan-based lubricant gel in reducing the risk of genital human papillomavirus (HPV) infections in women. METHODS: We conducted a planned interim analysis of a randomized, double-blind, placebo-controlled, phase 2B trial. Women aged 18 years and older were randomly assigned (1:1) to a carrageenan-based gel or a placebo gel to be self-applied every other day for the first month and before and after each intercourse during follow-up. Assessments were performed at 0.5, 1, 3, 6, 9 and 12 months. The primary outcome was incidence of a new infection by an HPV type that was not present at baseline. Intention-to-treat analyses were performed. RESULTS: Between January 2013 and June 2017, a total of 280 participants were randomly assigned to the carrageenan (n = 141) or the placebo (n = 139) arm. All participants were included in safety analyses, but three (1%) were excluded from efficacy analyses (HPV results unavailable for two participants in the carrageenan and one participant in the placebo arm). The median follow-up time was 9.2 months (interquartile range, 1.9-13.2 months). A total of 59 (42%) of 139 participants in the carrageenan arm and 78 (57%) of 138 participants in the placebo arm became infected by at least one new HPV type (hazard ratio = 0.64, 95% confidence interval = 0.45-0.89, p 0.009). A total of 62 (44%) of 141 participants in the carrageenan arm versus 43 (31%) of 139 participants in the placebo arm reported an adverse event (p 0.02), none of which was deemed related to the gels. CONCLUSIONS: Our trial's interim analysis suggests that using a carrageenan-based lubricant gel can reduce the risk of genital HPV infections in women.

Sexual behaviours and head and neck cancer: A systematic review and meta-analysis.

Human papillomaviruses (HPV) are associated with head and neck cancers (H&NC). Transmission of HPV to the upper aerodigestive tract occurs plausibly through sexual contact, although epidemiologic evidence on the role of sexual behaviours in H&NC aetiology is inconsistent. We conducted a meta-analysis of studies examining the association between four indicators of sexual behaviours (number of sexual partners and oral sex partners, oral sex practice, and age at first intercourse) and H&NC. Summary odds ratios (OR) and 95% confidence intervals (CI) were estimated using fixed and random effects models for each indicator, contrasting 'highest' to 'lowest', 'ever' to 'never', or 'youngest' to 'oldest' categories. Twenty case-control studies were included out of 3838 identified publications. Using random effects models, summary ORs suggested an increased risk of H&NC for number of sexual partners [OR=1.29, 95% CI: 1.02-1.63] (19 studies) and number of oral sex partners [OR=1.69, 95% CI: 1.00-2.84] (5 studies), whereas no effect was observed with oral sex practice [OR=1.09, 95% CI: 0.88-1.35] (17 studies) and age at first intercourse [OR=1.40, 95% CI: 0.71-2.79] (6 studies). For number of sexual partners and oral sex practice, which were assessed in more studies, we further excluded studies contributing to heterogeneity and those not adjusted for age, sex, smoking, and alcohol consumption. The summary ORs were 0.95 (95% CI: 0.75-1.20) for number of sexual partners and 1.03 (95% CI: 0.84-1.26) for oral sex practice. Our findings highlight that observed associations might be partly attributed to confounding effects of sociodemographic and behavioural factors.

Characterizing an ERP correlate of intentions understanding using a sequential comic strips paradigm.

Chronometric properties of theory of mind and intentions understanding more specifically are well documented. Notably, it was demonstrated using magnetoencephalography that the brain regions involved were recruited as soon as 200 ms post-stimulus. We used event-related potentials (ERPs) to characterize an electrophysiological marker of attribution of intentions. We also explored the robustness of this ERP signature under two conditions corresponding to either explicit instructions to focus on others' intentions or implicit instructions with no reference to mental states. Two matched groups of 16 healthy volunteers each received either explicit or no instructions about intentions and performed a nonverbal attribution of intentions task based on sequential four-image comic strips depicting either intentional or physical causality. A bilateral posterior positive component, ranging from 250 to 650 ms post-stimulus, showed greater amplitude in intentional than in physical condition (the intention ERP effect). This effect occurs during the third image only, suggesting that it reflects the integration of information depicted in the third image to the contextual cues given by the first two. The intention effect was similar in the two groups of subjects. Overall, our results identify a clear ERP marker of the first hundreds of milliseconds of intentions processing probably related to a contextual integrative mechanism and suggest its robustness by showing its blindness to task demands manipulation.

Is metal fume fever a determinant of welding related respiratory symptoms and/or increased bronchial responsiveness? A longitudinal study.

BACKGROUND: The current prospective study investigated the hypothesis of metal fume fever (MFF) being a predictor for the development of respiratory symptoms and functional abnormalities. METHODS: The study consisted of a pre-exposure and two follow up assessments of 286 welding apprentices during an average period of 15 months. A respiratory and a systemic symptom questionnaire, skin prick tests to common allergens and metal salts, spirometry, and methacholine challenge tests were administered. RESULTS: Developing at least one positive skin prick test to a metallic salt solution was found in 11.8% of apprentices. Possible MFF (at least one of fever, feelings of flu, general malaise, chills, dry cough, metallic taste, or shortness of breath) was reported by 39.2% of apprentices. The presence of at least one welding related respiratory symptom (cough, wheezing, or chest tightness) suggestive of welding related asthma was reported by 13.8%. MFF was significantly associated with these respiratory symptoms (OR = 4.92, 95% CI 2.10 to 11.52), after adjusting for age, atopy, smoking, physician diagnosed asthma, and symptoms of non-welding related asthma. Apprentices with possible MFF, and no welding related respiratory symptoms suggestive of welding related asthma at the first follow up, had an increased risk of developing the latter symptoms by the second follow up visit (OR = 7.4, 95% CI 1.97 to 27.45) compared with those not having MFF. MFF was not significantly associated with an increase in bronchial responsiveness. CONCLUSION: MFF could be a predictor for the development of respiratory symptoms but not for functional abnormalities in welders.

Incidence of probable occupational asthma and changes in airway calibre and responsiveness in apprentice welders.

The majority of cross-sectional studies have shown a higher prevalence of ventilatory impairment in welders while only few longitudinal studies were able to detect chronic effects on spirometry or bronchial responsiveness. The aim of the study was to determine the incidence of probable occupational asthma (OA), bronchial obstruction and hyperresponsiveness among 286 students entering an apprenticeship programme in the welding profession. This epidemiological prospective cohort study consisted of a baseline assessment survey and two follow-up assessments. A respiratory symptom questionnaire was administered at each visit. Spirometry and methacholine bronchial challenge test results, conducted once prior to onset of exposure and later after an average of 15 months of apprenticeship, were available for 194 subjects. The incidence of probable OA was approximately 3% (6 of 194). The incidence of bronchial hyperresponsiveness, defined as a > or = 3.2-fold decrease in the provocative concentration causing a 20% fall in the forced expiratory volume in one second from baseline to the end of the study was 11.9%. A statistically significant difference was found between the baseline and end of study for the lung function values. In particular, the forced expiratory volume per cent predicted had significantly dropped by 8.4% on average. The significance of these early pulmonary function changes in relation to possible chronic effects of exposure to welding fumes and gases remains to be explored.

Prevalence and association of welding related systemic and respiratory symptoms in welders.

BACKGROUND: The prevalence of welding related respiratory symptoms coexisting with welding related systemic symptoms in welders is unknown. AIMS: To determine in a sample of welders the prevalence of coexisting welding related systemic symptoms indicative of metal fume fever (MFF) and welding related respiratory symptoms suggestive of occupational asthma (OA), and the strength and significance of any association between these two groups of symptoms. METHODS: A respiratory symptoms questionnaire, a systemic symptoms questionnaire, and a questionnaire on occupational history were administered by telephone to 351 of a sample of 441 welders (79.6%) from two cities in Québec, Canada. RESULTS: The co-occurrence of possible MFF (defined as having at least two symptoms of fever, feelings of flu, general malaise, chills, dry cough, metallic taste, and shortness of breath, occurring at the beginning of the working week, 3-10 hours after exposure to welding fumes) together with welding related respiratory symptoms suggestive of OA (defined as having at least two welding related symptoms of cough, wheezing, and chest tightness) was 5.8%. These two groups of symptoms were significantly associated (chi(2) = 18.9, p < 0.001). CONCLUSION: There is a strong association between welding related MFF and welding related respiratory symptoms suggestive of OA. As such, MFF could be viewed as a pre-marker of welding related OA, a hypothesis that requires further investigation.

Clinical evaluation of serum aminoterminal propeptide of type III procollagen as tumor marker in gynecologic malignancies.

AIMS: The aim of this study was to determine the possible usefulness of the assay of the aminoterminal propeptide of type III procollagen and fibronectin in detecting connective tissue changes associated with gynecologic malignancies. STUDY DESIGN: Serum aminoterminal propeptide of type III procollagen and plasma fibronectin were measured in 36 women with gynecologic malignancies, 20 women with benign gynecologic tumors and 10 healthy women serving as controls. RESULTS: A significant serum propeptide was significantly high in the group with gynecologic malignancies and normal in the benign tumor group. The serum propeptide levels were related to of disease stage and presence of ascites in patients with ovarian carcinoma but not in those with cervical or endometrial carcinoma. In the follow-up study, a favorable clinical response was associated with normalizing propeptide levels whereas in rapidly progressive disease the levels fell initially but rose again. In partial response with ultimate progression, the propeptide concentration decreased but remained clearly above the normal range. No difference in plasma fibronectin was found among the malignant tumor, benign tumor and control groups. CONCLUSIONS: The present study indicates that the aminoterminal propeptide of type III procollagen could serve as an additional, non specific marker to follow the clinical behavior of gynecologic malignancies and consequently of connective tissue metabolism reflecting tumor matrix interaction.

Blood pressure responses to sucrose ingestion in four rat strains.

Among four strains examined, spontaneously hypertensive rats (SHR) show a marked (20 mm Hg, P less than .01) systolic blood pressure elevation (SBP), Sprague-Dawley (SD) and Wistar-Kyoto (WKY) rats developed a moderate elevation (8 mm Hg, P less than .01), and a normotensive Wistar rat (WAM) had a lesser SBP elevation (6 mm Hg, P = NS) after excess sucrose ingestion. The SBP elevations found in SHR were noted at 2 and 4 weeks after starting the dietary treatments. Corresponding with SBP changes, plasma renin activity (PRA), aldosterone, and neuropeptide Y (NPY) concentrations all decreased with the high sucrose-low protein diet compared to the low sucrose-high protein diet, while circulating insulin levels were unchanged. Although norepinephrine (NE) and epinephrine (E) excretion tended to be higher in the rats eating the high sucrose-low protein food, the differences were not statistically significant. The differences in these parameters could influence the SBP in SHR, SD, and WKY, but virtually similar qualitative and quantitative blood and urinary findings were found in WAM, a strain of rat that showed no significantly increased SBP. Removing one kidney increases the CHO-induced SBP response of WKY to levels comparable to those seen in SHR, converting a moderate responder to a highly sensitive one. We conclude that under well-controlled conditions there are obvious differences in the SBP response to the macronutrients in the diets of various rat strains and that SHR possess some intrinsic mechanism(s), most likely associated with renal metabolism, which make this strain more sensitive to refine CHO-induced SBP elevations.

Correlation of renal organic anion and cation transport with blood pressure in SHR.

In 1974, we found that sera from SHR suppressed renal PAH transport (PSEBM 145:97, 1974). Since a "natriuretic factor" depresses PAH as well as Na transport, we proposed that "natriuretic factor" was elevated in SHR. Our current investigation amplifies the previous study. On a given day, one spontaneously hypertensive rat (SHR) and one rat from a normotensive strain [Wistar Kyoto (WKY) or Sprague-Dawley (SD]) were examined together. SHR sera compared to WKY/SD sera significantly depress PAH (organic anion) and TEA (organic cation) uptake by rat renal slices. The ability of SHR sera to depress uptake correlated significantly with the BP: the sera with the greatest depressive influence on renal PAH and TEA uptake came from the SHR with the highest BP (PAH r = 0.89, p less than 0.0001; TEA = r = 0.76, p less than 0.01). Subsequent separation of serum on Sephadex 25 localized the factor to the same fraction as "natriuretic hormone". A similar correlation was found between the ability of the fraction to depress the 2 transports and the height of the BP. The serum factor did not inhibit ATPase activity. In contrast to the serum effects, renal slices removed from SHR showed increased rather than decreased PAH and TEA transport which significantly correlated with the BP. The slices with the highest uptakes came from the SHR with the highest BP. The high uptake of organic ions by the SHR renal slices could be an adaptive response to the serum factor or vice versa. We postulate that a serum factor which depresses PAH and TEA transport and is not "ouabain-like" may play a role in the BP elevation of SHR.

Development of sugar-induced blood pressure elevation after uninephrectomy in a resistant rat strain.

Certain rat strains acutely increase blood pressure (BP) when given diets high in NaCl. Prior results showed that "salt-sensitive" rat strains, at least the ones studied, also increase BP in response to sugar loading. To examine this relationship further and learn more about the pathogenesis of sucrose-induced BP elevations, we examined the effects of unilateral nephrectomy (uninephrectomy) on sucrose-induced BP changes. The rationale is based upon the findings that renal mass removal sensitizes BP response to salt loading. Over 15 weeks, augmented sugar (sucrose) consumption by Long-Evans (LE) rats did not increase BP markedly compared to rats consuming a diet relatively low in sugar unless uninephrectomy was performed. The differences in BP caused by the high sugar diet in a uninephrectomized rat could not be explained adequately by alterations in catecholamine excretion, plasma renin activity, excesses in blood volume, or the other parameters examined. However, salt-induced hypertension has been attributed to the presence of circulating substances affecting ion transport. Among the dietary groups, there was a significant correlation between the ability of plasma to depress PAH and TEA renal slice uptake and the difference in BP. This is consistent with the presence of a circulating factor affecting cell transport that has its greatest activity in the high sugar-uninephrectomy group of LE rats. We conclude that reducing renal mass potentiates sugar-induced BP elevation similar to salt-induced BP elevation in a normally resistant rat strain, and the rise of BP may be caused by a circulating factor.

Long-term effects of excess sucrose ingestion on three strains of rats.

We placed groups of spontaneously hypertensive rats (SHR), Wistar-Kyoto rats (WKY) and a local strain of normotensive Wistar rats on 5 different diets. Our baseline diet (I) derived a near equal number of calories from sucrose, proteins and fats, ie, 1/3 of total calories was provided by each macronutrient. Two other diets (II,III) derived the majority of calories from sucrose with less calories from proteins or fats respectively. The last two diets (IV,V) were relatively low in sucrose with a higher percentage of the total calories from proteins or fats respectively. The rats were assigned to the special diets at 3 months of age. They have now been ingesting these diets a total of 12 months. In SHR, the diets highest in sucrose calories (II,III), in contrast to diets I,IV and V, were associated with a markedly increased blood pressure (BP) at 3 months. The difference of approximately 20 to 30 mm Hg has held over 12 months. In contrast, the normotensive Wistar rats consuming diets II and III showed significant differences in BP (approximately 10 mm Hg) only after 12 months. The response of WKY was intermediate. Some clearcut elevation of BP, although not statistically significant, in WKY consuming diets II and III was present by 3 months. This difference became greater with time (20 mm Hg at 12 months). Consistent changes in body weights between the rats on the different diets were lacking. We conclude that excess ingestion of sucrose can cause chronic elevations in BP, the pattern of which varies among rat strains.

Excess sucrose and glucose ingestion acutely elevate blood pressure in spontaneously hypertensive rats.

Spontaneously hypertensive rats (SHR) were fed 6 different diets. The baseline diet (I) derived equal calories from sucrose, proteins, and fats. Three other diets (II, III, VI) derived the majority of calories from refined CHO, sucrose or glucose, with decreases in calories from proteins or fats. The last two diets (IV, V) were relatively low in sucrose with a higher percentage of the total calories from proteins and fats, respectively. From 3 to 15 weeks on the diets, the highest average BP was in rats consuming high concentrations of sucrose or glucose (II, III, VI). Urinary excretory rates of norepinephrine (NE) at 5, 10 and 15 weeks and epinephrine at 5 and 10 weeks were significantly elevated in rats ingesting diets high in refined CHO, and NE positively correlated with blood pressure (BP) at 5 and 10 weeks of the study. At the end of the study, serum insulin levels were not different, but plasma renin and serum glucagon levels were lower in SHR consuming the diets with high CHO concentrations. We conclude that equally elevated BP are seen with relatively high intakes of either sucrose or glucose, whether the balance of calories is derived from lessening fat or protein. This is secondary, at least in part, to alterations in NE metabolism.

Effect of sodium and potassium ingestion on renal growth in rats.

To determine whether differences in dietary Na and K intake influence renal growth and compensatory renal growth following unilateral nephrectomy (uni), rats were given 2 diets for 2 weeks which differed only in Na-K concentrations. Diet 1 (High Na, Low K) contained 1.0% Na, 0.36% K and diet 2 (Low Na, High K) contained 0.05% Na, 2.0% K. Half of the rats consuming diets 1 and 2 for 1 week received uni and the other half of sham operation (sham). The rats were followed for another week while consuming the experimental diets. Uni and sham rats on diet 1 showed significant increase in blood pressure (BP) (136 +/- 4 v 126 +/- 3 mm Hg, P less than .05). Uni itself did not alter blood pressure. Body weight and heart rate were unchanged by diet or operation. Kidney weight, renal RNA, protein, RNA/DNA, and protein/DNA increased significantly after uni but the differences were not affected by diet. Serum blood urea nitrogen (BUN) and creatinine were not markedly different among any group of rats suggesting no major renal damage. We conclude that dietary changes of Na-K which cause no obvious renal damage even though BP is elevated moderately do not influence renal growth or compensatory renal growth. Based on RNA, DNA and protein metabolism, the form of growth (hypertrophy or hyperplasia) is also not influenced by renal electrolyte handling.

Influence of oat bran on sucrose-induced blood pressure elevations in SHR.

To determine whether oat fiber influences BP, we gave spontaneously hypertensive rats (SHR) a diet high in sucrose and low in protein (calories: sucrose 52%, protein 15%, fat 33%) or a diet low in sucrose and high in protein (calories: sucrose 13%, protein 52%, fat 35%). The amount of fat in these particular diets has not been shown to influence BP, so we modified the 2 diets by replacing fat with oat bran (10% w/w). Accordingly, we examined 4 groups of 5 rats consuming different diets: high sucrose, high sucrose + oat bran, low sucrose, and low sucrose + oat bran. Not unexpectedly, SHR consuming the diet high in sucrose had a significantly higher BP after 2 weeks than those consuming the diet low in sucrose. The significant difference in BP continued over the next 3 weeks. At the end of 6 week duration of study, we found the following BP: SHR ingesting the high sucrose diet, 217 mm Hg +/- 5 (SEM) vs SHR consuming the low sucrose diet, 187 mm Hg +/- 4 (SEM) p less than .0001]. SHR eating the low sucrose diet and consuming supplemental bran showed no significant change in BP after 6 weeks compared to SHR eating the basic diet alone, 188 mm Hg +/- 6 (SEM); however, 5 SHR consuming the high sucrose diet with added oat bran showed a significantly lower BP 200 mm Hg +/- 2 (SEM) than SHR ingesting the basic high sucrose diet devoid of oat bran [p less than .01]. We conclude that addition of oat bran to the diet can ameliorate sucrose-induced BP elevations in SHR.