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.     

Predoctoral fixed implant patient satisfaction outcome and challenges of a clinical implant competency

Treatment with fixed and removable partial dentures has been the traditional method of addressing the replacement of teeth competencies in dental education. However, by 2013 the Commission on Dental Accreditation (CODA) standards will mandate a competency in "replacement of teeth including fixed, removable, and dental implants." In 2005, New York University College of Dentistry implemented a comprehensive implant program for predoctoral dental students. One of the outcome assessments of this program was to determine the level of patient satisfaction. Therefore, a patient satisfaction survey (n=103) assessed the use of implant treatment for the restoration of partially edentulous patients, measuring such dimensions of satisfaction as function, comfort, and esthetics. The results revealed that 96 percent of the patients surveyed were satisfied with their ability to chew, 91 percent were satisfied with the comfort of their restoration, and 86 percent were satisfied with the appearance of their restoration. Additionally, 90 percent of the surveyed patients who received implant-retained crowns as part of their routine care were satisfied with the overall treatment experience, and 97 percent of them would recommend this treatment to a friend. The survey results validate implant-supported crown treatment in predoctoral education. Although implant-supported restorations are a valid treatment option that must be presented to patients during treatment planning, creating a clinical competency in implant therapy requires greater consideration. Therefore, the benefits and challenges of such a clinical competency are discussed.     

Determination of toxic element levels (lead and cadmium) in commonly used cosmetic products in Iran

Toxic elements are commonly used in cosmetic products for many reasons like coloring pigments or blocking ultraviolet light; however, the level of some metals exceed specific concentration which can cause serious safety issues. This study aims to evaluate the content of lead and cadmium in samples of sunscreen and foundation creams, most frequently used brands of cosmetic products, in Iran. Concentration of lead in the sunscreens and foundation creams was lower than that of USFDA standards. The content of cadmium was higher than Europe Union standard. Effort must be made to inform the users about the harmful consequences of cosmetics.     

Weighted Fourier analysis of blood pressure curves after lisinopril versus atenolol administration in young hypertensives

OBJECTIVE: To evaluate and compare the effects of lisinopril versus atenolol administration on the diurnal blood pressure profile and the nocturnal blood pressure fall in young mild-to-moderate essential hypertensives.METHODS: Thirty patients were studied. After a 2-week placebo run-in period, they were single-blind randomly assigned to receive 20 mg lisinopril or 100 mg atenolol. Using a SpaceLabs 90207 device, their ambulatory blood pressure was measured before and after 12 weeks of therapy. The readings were analysed using Fourer series with four harmonics. RESULTS: Lisinopril and atenolol administration significantly decreased office and ambulatory blood pressure values compared with the placebo period. The daily blood pressure curves obtained from Fourier analysis showed that the circadian rhythm was not altered by lisinopril and atenolol administration. From the night:day ratio for the nocturnal blood pressure fall, we found that atenolol administration minimized the average night-time blood pressure dip by increasing the number of non-dippers. In contrast, lisinopril administration did not modify the day-night difference, preserving the nocturnal blood pressure fall. CONCLUSION: Lisinopril and atenolol administration as a first-step treatment of young essential hypertensives produced comparable degrees of diurnal control of arterial pressure. The blood pressure fall at night in patients treated with atenolol was slightly less than that found with lisinopril treatment.     

The association between hematological parameters and metabolic syndrome in Iranian men: A single center large-scale study

Aims

Some studies have demonstrated that metabolic syndrome is associated with hematological parameters. The present study explores the relationship between hematological parameters and numbers of metabolic syndrome conditions in Iranian men.

Controlled release from a mechanically-stimulated thermosensitive self-heating composite hydrogel

Temperature has been extensively explored as a trigger to control the delivery of a payload from environment-sensitive polymers. The need for an external heat source only allows limited spatiotemporal control over the delivery process. We propose a new approach by using the dissipative properties of a hydrogel matrix as an internal heat source when the material is mechanically loaded. The system is comprised of a highly dissipative hydrogel matrix and thermo-sensitive nanoparticles that shrink upon an increase in temperature. Exposing the hydrogel to a cyclic mechanical loading for a period of 5 min leads to an increase of temperature of the nanoparticles. The concomitant decrease in the volume of the nanoparticles increases the permeability of the hydrogel network facilitating the release of its payload. As a proof-of-concept, we showed that the payload of the hydrogel is released after 5–8 min following the initiation of the mechanical loading. This delivery method would be particularly suited for the release of growth factor as it has been shown that cell receptor to growth factor is activated 5–20 min following a mechanical loading.