Environmental mercury exposure,semen quality and reproductive hormones in Greenlandic Inuit and European men: a cross-sectional study

Several animal studies indicate that mercury is a male reproductive toxicant, but human studies are few and contradictory. We examined semen characteristics and serum levels of reproductive hormones in relation to environmental exposure to mercury. Blood and semen samples were collected from 529 male partners of pregnant women living in Greenland, Poland and Ukraine between May 2002 and February 2004. The median concentration of the total content of mercury in whole blood was 9.2 ng ml⁻¹ in Greenland (0.2–385.8 ng ml⁻¹), 1.0 ng ml⁻¹ in Poland (0.2–6.4 ng ml⁻¹) and 1.0 ng ml⁻¹ in Ukraine (0.2–4.9 ng ml⁻¹). We found a significantly positive association between the blood levels of mercury and serum concentration of inhibin B in men from Greenland (β=0.074, 95% confidence interval (CI)=0.021 to 0.126) and in an analysis including men from all three regions (β=0.067, 95% CI=0.024 to 0.110). The association may be due to beneficial effects of polyunsaturated fatty acids (PUFAs), which are contained in seafood and fish. No significant association (P>0.05) was found between blood concentrations of mercury and any of the other measured semen characteristics (semen volume, total sperm count, sperm concentration, morphology and motility) and reproductive hormones (free androgen index (FAI), follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone and LH×testosterone) in any region. In conclusion, the findings do not provide evidence that environmental mercury exposure in Greenlandic and European men with median whole blood concentration up to 10 ng ml⁻¹ has adverse effects on biomarkers of male reproductive health.     

Right ventricular assessment at cardiac MRI: initial clinical experience utilizing an IS-SENSE reconstruction

Cardiac MR is considered the gold standard in assessing RV function. The purpose of this study is to evaluate the clinical utility of an investigational iterative reconstruction algorithm in the quantitative assessment of RV function. This technique has the potential to improve the clinical utility of CMR in the evaluation of RV pathologies, particularly in patients with dyspnea, by shortening acquisition times without adversely influencing imaging performance. Segmented cine images were acquired on 9 healthy volunteers and 29 patients without documented RV pathologies using conventional GRAPPA acquisition with factor 2 acceleration (GRAPPA 2), a spatio-temporal TSENSE acquisition with factor 4 acceleration (TSENSE 4), and iteratively reconstructed Sparse SENSE acquisition with factor 4 acceleration (IS-SENSE 4). 14 subjects were re-analyzed and intraclass correlation coefficients (ICC) were calculated and Bland–Altman plots generated to assess agreement. Two independent reviewers qualitatively scored images. Comparison of acquisition techniques was performed using univariate analysis of variance (ANOVA). Differences in RV EF, BSA-indexed ESV (ESVi), BSA-indexed EDV (EDVi), and BSA-indexed SV (SVi) were shown to be statistically insignificant via ANOVA testing. R² values for linear regression of TSENSE 4 and IS-SENSE 4 versus GRAPPA 2 were 0.34 and 0.72 for RV-EF, and 0.61 and 0.76 for RV-EDVi. ICC values for intraobserver and interobserver quantification yielded excellent agreement, and Bland–Altman plots assessing agreement were generated as well. Qualitative review yielded small, but statistically significant differences in image quality and noise between TSENSE 4 and IS-SENSE 4. All three techniques were rated nearly artifact free. Segmented imaging acquisitions with IS-SENSE reconstruction and an acceleration factor of 4 accurately and reliably quantitates RV systolic function parameters, while maintaining image quality. TSENSE-4 accelerated acquisitions showed poorer correlation to standard imaging, and inferior interobserver and intraobserver agreement. IS-SENSE has the potential to shorten cine acquisition times by 50?%, improving imaging options in patients with intermittent arrhythmias or difficulties with breath holding.     

Le « poids » du médecin traitant dans l’initiation d’une chirurgie bariatrique

Background

Bariatric surgery is developing at a fast pace. It involves a large number of health care professionals. Among those, general practitioners should have an outstanding position: obesity diagnosis, initial medical management, advising and possibly referring the patient to surgical intervention, participating in the post-surgical follow-up. This study aims at assessing the actual role of general practitioners in initiating bariatric surgery.

Materials and methods

Questionnaires were sent to general practitioners who had one patient undergoing bariatric surgery in Dijon University Hospital between March 2013 and April 2015. The questionnaire addressed the health care history of patients before surgery, the impressions of the general practitioners regarding their role and their knowledge about that type of surgery, and the relationships between the general practitioners and the hospital multi-disciplinary team.

Results

Among the 48 general practitioners who received questionnaires, 39 have answered. 19 of them had given positive advice to a surgical intervention, but only 8 had taken the initiative to recommend it. Once the decision to operate was made, 21 general practitioners offered their patients an ad hoc medical follow-up, whereas 18 relied entirely upon the hospital team for patient treatment. Although 22 general practitioners had some reserves on bariatric surgery in the first place, 23 were in favour of such surgery after their patients were operated on. 33 general practitioners out of 39 were strongly in favour of liaison data sheets, but most general practitioners apparently did not wish to play a more important role in the treatment decision (32 of them declined to be involved in the hospital multi-disciplinary team).

Conclusion

The role of general practitioners concerning the bariatric surgery is still evolving. General practitioners are often involved in the medical treatment of obesity but they seem to be less active in the initiation of surgical treatment, although they support and advise their patients. Better training and information on this topic increase the confidence that general practitioners have in this type of surgery, thus improving the peri-operative management of patients and the subsequent medical follow-up, in which general practitioners have a prominent part to play.

     

Post-genomic platform for development of oligonucleotide vaccines against RNA viruses: diamond cuts diamond

Inflammation Research - The coronavirus pandemic has starkly demonstrated the need to create highly effective vaccines against various viral diseases. The emerging new platforms for vaccine...     

Hemispheric asymmetry in global/local processing: effects of stimulus position and spatial frequency

We examined the neural mechanisms of functional asymmetry between hemispheres in the processing of global and local information of hierarchical stimuli by measuring hemodynamic responses with functional magnetic resonance imaging (fMRI). In a selective attention task, subjects responded to targets at the global or local level of compound letters that were (1) broadband in spatial-frequency spectrum and presented at fixation; (2) broadband and presented randomly to the left or the right of fixation; or (3) contrast balanced (CB) to remove low spatial frequencies (SFs) and presented at fixation. Central broadband stimuli induced stronger activation in the right middle occipital cortex under global relative to local attention conditions but in the left inferior occipital cortex, stronger activation was induced under local relative to global attention conditions. The asymmetry over the occipital cortex was weakened by unilateral presentation and by contrast balancing. The results indicate that the lateralization of global and local processing is modulated by the position and SF spectrum of the compound stimuli. The global attention also produced stronger activation over the medial occipital cortex relative to the local attention under all the stimulus conditions. The nature of these effects is discussed.     

Chagas' disease diagnosis: a multicentric evaluation of Chagas Stat-Pak,a rapid immunochromatographic assay with recombinant proteins of Trypanosoma cruzi

A rapid serologic test for diagnosis of T. cruzi infection (Chagas Stat Pak) was developed using recombinant proteins in an immunochromatographic assay. This cassette format test was evaluated first in blind with a panel of 393 coded serum samples. The Chagas Stat-Pak identified 197 infected (98.5% sensitivity) and 183 non-infected individuals (94.8% specificity). A second evaluation was performed with 352 sera from four Latin America countries tested independently in each country, showing a sensitivity of 100% and specificity of 98.6%. A third set of tests comparing sera with plasma and eluates from filter paper as well as serum preserved in 50% glycerol did show identical results as those obtained with serum. This rapid test (15 min) uses one device per sample, does not require refrigeration nor a laboratory structure or specialized skills to be performed, accepts different types of samples and may be stored for long periods of time for result checking and documentation. These attributes together with the high sensitivity and specificity demonstrated herein, make this test a suitable tool for field studies, small laboratories and emergencies at blood banks in the countryside of endemic areas.     

Differential effects of U46619 on renal regional hemodynamics in the rat: involvement of endothelin

Many vasoactive agents produce qualitatively similar effects on blood flow in the renal cortex and medulla, evoking reductions or increases in blood flow in both regions. We demonstrated previously that endothelin-1 (ET-1) is an exception because it evoked an increase in medullary perfusion despite a potent cortical vasoconstriction ( Hercule and Oyekan 2000). We report here that U46619 (11,9 epoxymethano-prostaglandin H2), a selective agonist of prostaglandin H2 (PGH2)/thromboxane A2 (TxA2) (TP) receptor, evokes similar effects as ET-1. In the pentobarbital-anesthetized (60 mg/kg) rat, 1, 3, and 5 microg/kg U46619 dose dependently reduced mean arterial blood pressure by -2 +/- 4, -8 +/- 10, and -31 +/- 10 mm Hg, respectively; renal cortical blood flow (CBF) by -50 +/- 11, -174 +/- 45, and -349 +/- 43 perfusion units (PU), respectively; but increased medullary blood flow (MBF) by 42 +/- 16, 51 +/- 18, and 61 +/- 21 PU, respectively. Prostaglandin F2alpha, a TxA2 mimetic, produced similar effects as U46619. SQ29548 ([1S-[1alpha,2alpha(Z), 3alpha,4alpha]]-7-[3[[2-[(phenylamino)carbonyl[hydrazino] methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid) (0.1 mg/kg), an antagonist of PGH2/TxA2 (TP), blunted U46619-induced hemodynamic changes without affecting that produced by phenylephrine. BMS182874 [5-(dimethylamino)-N-(3,4-dimethyl-5-isoxazolyd)-1-naphthalene sulfonamide] (40 mg/kg), an ET(A)-selective antagonist, blunted U46619-induced reduction in CBF by 54 +/- 9% (p < 0.05) and the increase in MBF by 59 +/- 18% (p < 0.05). Similarly, BQ788 (N-cis 2,6-dimethylpiperidinocarbonyl-L-gamma-methylleucyl-D-1-methoxycarbonyltryptophanyl-D-norleucine) (1 mg/kg), an ET(B)-selective antagonist, blunted the effects of U46619 on CBF and MBF by 19 +/- 3% (p < 0.05) and 48 +/- 19% (p < 0.05), respectively. Combined administration of BMS182874 and BQ788 further attenuated U46619-induced reduction in CBF by 67 +/- 8% (p < 0.05) and that on MBF by 61 +/- 18% (p < 0.05). Phosphoramidon (10 mg/kg), an endothelin converting enzyme inhibitor, markedly blunted U46619-induced changes on CBF and MBF (p < 0.05). These findings are the first to demonstrate that U46619, through activation of ET(A) and ET(B) receptors, elicits renal cortical vasoconstriction and medullary vasodilation in the rat.