128 research outputs found
A compilation of field surveys on gaseous elemental mercury (GEM) from contrasting environmental settings in Europe, South America, South Africa and China: separating fads from facts
Mercury is transported globally in the atmosphere
mostly in gaseous elemental form (GEM, Hg0
gas),
but still few worldwide studies taking into account
different and contrasted environmental settings are
available in a single publication. This work presents
and discusses data from Argentina, Bolivia, Bosnia
and Herzegovina, Brazil, Chile, China, Croatia, Finland,
Italy, Russia, South Africa, Spain, Slovenia and
Venezuela. We classified the information in four
groups: (1) mining districts where this contaminant
poses or has posed a risk for human populations and/or
ecosystems; (2) cities, where the concentration ofatmospheric mercury could be higher than normal due
to the burning of fossil fuels and industrial activities;
(3) areas with natural emissions from volcanoes; and
(4) pristine areas where no anthropogenic influence
was apparent. All the surveys were performed using
portable LUMEX RA-915 series atomic absorption
spectrometers. The results for cities fall within a low
GEM concentration range that rarely exceeds 30 ng m-3,
that is, 6.6 times lower than the restrictive ATSDR
threshold (200 ng m-3) for chronic exposure to this
pollutant. We also observed this behavior in the former
mercury mining districts, where few data were above
200 ng m-3.We noted that high concentrations of GEM
are localized phenomena that fade away in short
distances. However, this does not imply that they do not
pose a risk for those working in close proximity to the
source. This is the case of the artisanal gold miners that
heat the Au–Hg amalgam to vaporize mercury. In this
respect, while GEM can be truly regarded as a hazard,
because of possible physical–chemical transformations
into other species, it is only under these localized
conditions, implying exposure to high GEM concentrations,
which it becomes a direct risk for humans.Grants
CGL2009-13171 and CTM2012-33918 from the Spanish
Ministry of Economy and Competitiveness and PII1I09-0142-
4389 from theCastilla-LaMancha (Spain)RegionalGovernment.Published713-7346A. Monitoraggio ambientale, sicurezza e territorioJCR Journalrestricte
Effect of garlic on blood pressure: A systematic review and meta-analysis
The electronic version of this article is the complete one and can be found online at the publisher's website.Background: Non-pharmacological treatment options for hypertension have the potential to reduce the risk of cardiovascular disease at a population level. Animal studies have suggested that garlic reduces blood pressure, but primary studies in humans and non-systematic reviews have reported mixed results. With interest in complementary medicine for hypertension increasing, it is timely to update a systematic review and meta-analysis from 1994 of studies investigating the effect of garlic preparations on blood pressure. Methods: We searched the Medline and Embase databases for studies published between 1955 and October 2007. Randomised controlled trials with true placebo groups, using garlic-only preparations, and reporting mean systolic and/or diastolic blood pressure (SBP/DBP) and standard deviations were included in the meta-analysis. We also conducted subgroup meta-analysis by baseline blood pressure (hypertensive/normotensive), for the first time. Meta-regression analysis was performed to test the associations between blood pressure outcomes and duration of treatment, dosage, and blood pressure at start of treatment. Results: Eleven of 25 studies included in the systematic review were suitable for meta-analysis. Meta-analysis of all studies showed a mean decrease of 4.6 ± 2.8 mm Hg for SBP in the garlic group compared to placebo (n = 10; p = 0.001), while the mean decrease in the hypertensive subgroup was 8.4 ± 2.8 mm Hg for SBP (n = 4; p < 0.001), and 7.3 ± 1.5 mm Hg for DBP (n = 3; p < 0.001). Regression analysis revealed a significant association between blood pressure at the start of the intervention and the level of blood pressure reduction (SBP: R = 0.057; p = 0.03; DBP: R = -0.315; p = 0.02). Conclusion: Our meta-analysis suggests that garlic preparations are superior to placebo in reducing blood pressure in individuals with hypertension.Karin Ried, Oliver R. Frank, Nigel P. Stocks, Peter Fakler and Thomas Sulliva
What can we say about today's British religious young person? Findings from the AHRC/ESRC Religion and Society Programme
Metabolic Syndrome and Cardiovascular Disease after Hematopoietic Cell Transplantation: Screening and Preventive Practice Recommendations from the CIBMTR and EBMT
Metabolic syndrome (MetS) is a constellation of cardiovascular risk factors that increases the risk of cardiovascular disease, diabetes mellitus, and all-cause mortality. Long-term survivors of hematopoietic cell transplantation (HCT) have a substantial risk of developing MetS and cardiovascular disease, with an estimated prevalence of MetS of 31% to 49% among HCT recipients. Although MetS has not yet been proven to impact cardiovascular risk after HCT, an understanding of the incidence and risk factors for MetS in HCT recipients can provide the foundation to evaluate screening guidelines and develop interventions that may mitigate cardiovascular-related mortality. A working group was established through the Center for International Blood and Marrow Transplant Research and the European Group for Blood and Marrow Transplantation with the goal to review literature and recommend practices appropriate to HCT recipients. Here we deliver consensus recommendations to help clinicians provide screening and preventive care for MetS and cardiovascular disease among HCT recipients. All HCT survivors should be advised of the risks of MetS and encouraged to undergo recommended screening based on their predisposition and ongoing risk factors
Sulfur-Directed Olefin Oxidations: Observation of Divergent Reaction Mechanisms in the Palladium-Mediated Acetoxylation of Unsaturated Thioacetals
The Pd-mediated oxidation of unsaturated thioacetals gives either allyl or vinyl esters, depending on the substrate structure. We report the characterization of a range of sulfur-stabilized palladium intermediates via a combined computational and experimental NMR approach, demonstrating that the oxidation proceeds via two divergent reaction mechanisms. We were also able to synthesize an unusual sigma-bound Pd complex, via acetoxypalladation of an unsaturated dithiane, which was characterized by X-ray crystallography
Intelligent Identification of Childhood Musical Murmurs
Heart murmurs are often the first signs of heart valvular disorders. However, most heart murmurs detected in children are innocent musical murmurs (also called Still's murmurs), which should be distinguished from other murmur types that are mostly pathological, such as regurgitant, obstructive, and flow murmurs. In order to reduce both unnecessary healthcare expenditures and parental anxiety, this study aims to develop algorithms for intelligently identifying musical murmurs in children. Discrete wavelet transform was applied to phonocardiographic signals to extract features. Singular value decomposition was applied on the matrix derived from continuous wavelet transform to extract extra features. The sequential forward feature selection algorithm was then utilized to select significant features. Musical murmurs were subsequently differentiated via a classification procedure consisting of three classification techniques: discriminant analysis, support vector machine, and artificial neural network. The results of 89.02% sensitivity, 84.76% specificity and 87.36% classification accuracy were achieved
Kawasaki syndrome: an intriguing disease with numerous unsolved dilemmas
More than 40 years have passed since Kawasaki syndrome (KS) was first described. Yet KS still remains an enigmatic illness which damages the coronary arteries in a quarter of untreated patients and is the most common cause of childhood-acquired heart disease in developed countries. Many gaps exist in our knowledge of the etiology and pathogenesis of KS, making improvements in therapy difficult. In addition, many KS features and issues still demand further efforts to achieve a much better understanding of the disease. Some of these problem areas include coronary artery injuries in children not fulfilling the classic diagnostic criteria, genetic predisposition to KS, unpredictable ineffectiveness of current therapy in some cases, vascular dysfunction in patients not showing echocardiographic evidence of coronary artery abnormalities in the acute phase of KS, and risk of potential premature atherosclerosis. Also, the lack of specific laboratory tests for early identification of the atypical and incomplete cases, especially in infants, is one of the main obstacles to beginning treatment early and thereby decreasing the incidence of cardiovascular involvement. Transthoracic echocardiography remains the gold-standard for evaluation of coronary arteries in the acute phase and follow-up. In KS patients with severe vascular complications, more costly and potentially invasive investigations such as coronary CT angiography and MRI may be necessary. As children with KS with or without heart involvement become adolescents and adults, the recognition and treatment of the potential long term sequelae become crucial, requiring that rheumatologists, infectious disease specialists, and cardiologists cooperate to develop specific guidelines for a proper evaluation and management of these patients. More education is needed for physicians and other professionals about how to recognize the long-term impact of systemic problems related to KS
Effect of garlic on cardiovascular disorders: a review
Garlic and its preparations have been widely recognized as agents for prevention and treatment of cardiovascular and other metabolic diseases, atherosclerosis, hyperlipidemia, thrombosis, hypertension and diabetes. Effectiveness of garlic in cardiovascular diseases was more encouraging in experimental studies, which prompted several clinical trials. Though many clinical trials showed a positive effect of garlic on almost all cardiovascular conditions mentioned above, however a number of negative studies have recently cast doubt on the efficary of garlic specially its cholesterol lowering effect of garlic. It is a great challenge for scientists all over the world to make a proper use of garlic and enjoy its maximum beneficial effect as it is the cheapest way to prevent cardiovascular disease. This review has attempted to make a bridge the gap between experimental and clinical study and to discuss the possible mechanisms of such therapeutic actions of garlic
Identification of Residues in DmsD for Twin-Arginine Leader Peptide Binding, Defined through Random and Bioinformatics-Directed Mutagenesis
Ischaemic conditioning and targeting reperfusion injury: a 30 year voyage of discovery
To commemorate the auspicious occasion of the 30th anniversary of IPC, leading pioneers in the field of cardioprotection gathered in Barcelona in May 2016 to review and discuss the history of IPC, its evolution to IPost and RIC, myocardial reperfusion injury as a therapeutic target, and future targets and strategies for cardioprotection. This article provides an overview of the major topics discussed at this special meeting and underscores the huge importance and impact, the discovery of IPC has made in the field of cardiovascular research
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