389 research outputs found

    Lead exposure in adult males in urban Transvaal Province, South Africa during the apartheid era

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    Human exposure to lead is a substantial public health hazard worldwide and is particularly problematic in the Republic of South Africa given the country’s late cessation of leaded petrol. Lead exposure is associated with a number of serious health issues and diseases including developmental and cognitive deficiency, hypertension and heart disease. Understanding the distribution of lifetime lead burden within a given population is critical for reducing exposure rates. Femoral bone from 101 deceased adult males living in urban Transvaal Province (now Gauteng Province), South Africa between 1960 and 1998 were analyzed for lead concentration by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Of the 72 black and 29 white individuals sampled, chronic lead exposure was apparent in nearly all individuals. White males showed significantly higher median bone lead concentration (ME = 10.04 ”g·g−1), than black males (ME = 3.80 ”g·g−1) despite higher socioeconomic status. Bone lead concentration covaries significantly, though weakly, with individual age. There was no significant temporal trend in bone lead concentration. These results indicate that long-term low to moderate lead exposure is the historical norm among South African males. Unexpectedly, this research indicates that white males in the sample population were more highly exposed to lead

    Pristup procjeni zdravstvenoga rizika za ljude prilikom izgradnje gradskoga parka

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    A Human Health Risk Assessment (HHRA) was undertaken for a proposed park development “River Landing”, to be constructed along the north bank of the South Saskatchewan River in the City of Saskatoon, Saskatchewan, Canada. The purpose of the HHRA was to determine whether chemical constituents identified at the site, including polycyclic aromatic hydrocarbons (PAHs), petroleum hydrocarbons (PHCs), and toxic and heavy metals, would adversely affect the health of construction workers and potential park users. Although more traditional remediation options were considered, the risk assessment approach was chosen since it represented the best available technology. The HHRA was undertaken using protocols and methodologies proposed and readily accepted by the Canadian Council of Ministers of the Environment (CCME), Health Canada, and the United States Environmental Protection Agency (US EPA). Results of the risk assessment revealed that the magnitude and distribution of the chemicals at the site were such that extensive remediation was not required, and that the site could be developed without any significant restrictions on the proposed use. The assessment revealed that potential exposure to soil constituents would not result in adverse health risk to construction workers involved in park development or future park users.Napravljena je procjena zdravstvenoga rizika za ljude (izv. human health risk assessment, HHRA) za projekt gradskoga parka “River Landing” koji bi se trebao izgraditi duĆŸ sjeverne obale rijeke South Saskatchewan u Saskatoonu, saveznoj drĆŸavi Saskatchewan u Kanadi. Svrha je procjene bila utvrditi mogu li kemijski spojevi zatečeni na gradiliĆĄtu, uključujući policikličke aromatske ugljikovodike, naftne ugljikovodike te toksične i teĆĄke metale, ĆĄtetno utjecati na zdravlje građevinskih radnika i korisnika parka. Premda je razmotrena i uporaba tradicionalnijih metoda sanacije, izabran je ovaj pristup procjeni rizika zbog toga ĆĄto rabi najbolju dostupnu tehnologiju. Procjena rizika provedena je prema protokolima i metodama koje je odmah usvojio Kanadski savjet ministara za zaĆĄtitu okoliĆĄa (izv. Canadian Council of Ministers of the Environment, CCME), savezni ured za zdravlje Health Canada te Agencija za zaĆĄtitu okoliĆĄa Sjedinjenih DrĆŸava (izv. United States Environmental Protection Agency, US EPA). Procjena rizika pokazala je da količina i rasprostranjenost kemikalija na gradiliĆĄtu nisu takvi da zahtijevaju opseĆŸniju sanaciju, te da se lokacija moĆŸe izgraditi bez značajnih ograničenja u namjeni. Procjenom je također utvrđeno da eventualno izlaganje sastavnicama tla neće dovesti do ĆĄtetnih posljedica za zdravlje građevinskih radnika koji rade na parku, a niti za buduće korisnike parka

    Toksični učinci olova u profesionalno izloĆŸene indijske obitelji

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    This article describes an entire family manufacturing lead acid batteries who all suffered from lead poisoning. The family of five lived in a house, part of which had been used for various stages of battery production for 14 years. Open space was used for drying batteries. They all drank water from a well located on the premises. Evaluation of biomarkers of lead exposure and/or effect revealed alarming blood lead levels [(3.92±0.94) ”mol L-1], 50 % reduction in the activity of ÎŽ-aminolevulinic acid dehydratase [(24.67±5.12) U L-1] and an increase in zinc protoporphyrin [(1228±480) ”g L-1]. Liver function tests showed an increase in serum alkaline phosphatase [(170.41±41.82) U L-1]. All other liver function test parameters were normal. Renal function tests showed an increase in serum uric acid [(515.81±86.29) ”mol L-1] while urea and creatinine were normal. Serum calcium was low [(1.90±0.42) mmol L-1 in women and (2.09±0.12) mmol L-1 in men], while blood pressure was high in the head of the family and his wife and normal in children. Lead concentration in well water was estimated to 180 ”g L-1. The family was referred to the National Referral Centre for Lead Poisoning in India, were they were received treatment and were informed about the hazards of lead poisoning. A follow up three months later showed a slight decrease in blood lead levels and a significant increase in haemoglobin. These findings can be attributed to behavioural changes adopted by the family, even though they continued producing lead batteries.Olovo je sveprisutni metal s mnogo namjena, a čovječanstvo ga rabi već viĆĄe od 6000 godina. Danas je olovo među najrasprostranjenijim toksinima u okoliĆĄu, a drugi je na popisu toksičnih metala, odmah iza arsena. Mnogi joĆĄ nisu svjesni njegova toksičnoga djelovanja te se i dalje izlaĆŸu olovu. Ovdje je opisana obitelj koja proizvodi olovne akumulatore i koja je pretrpjela trovanje olovom zahvaljujući svojoj neobavijeĆĄtenosti. Ova peteročlana obitelj ĆŸivjela je u jednome kućanstvu čiji je dio namijenjen različitim fazama proizvodnje akumulatora već 14 godina. Akumulatori su se suĆĄili na otvorenome. Na imanju je bio i bunar s pitkom vodom. Mjerenja biopokazatelja izloĆŸenosti olovu i njegova djelovanja u svih pet članova obitelji dovela su do alarmantnoga saznanja o razinama olova u krvi [(3,92±0,94) ”mol L-1], 50 %-tnom padu aktivnosti dehidrataze ÎŽ-aminolevulinske kiseline [(24,67±5,12) U L-1] te poviĆĄenom cinkovu protoporfirinu [(1228±480) ”g L-1]. Jetrene probe otkrile su poviĆĄene razine alkalne fosfataze u serumu [(170,41±41,82) U L-1]. Ostali su parametri jetrene funkcije bili normalni. Testovi funkcije bubrega otkrili su poviĆĄene razine mokraćne kiseline u serumu [(515,81±86,29) ”mol L-1], dok su razine ureje i kreatinina bile normalne. Također je zabiljeĆŸen pad razina kalcija u serumu [(1,90±0,42) mmol L-1 u ĆŸena te (2,09±0,12) mmol L-1 u muĆĄkaraca]. PoviĆĄeni krvni tlak zamijećen je u glave obitelji i njegove supruge, dok je u djece bio normalan. Koncentracija olova u bunarskoj vodi bila je izrazito visoka, prema procjeni 180 ”g L-1. Obitelj je upućena u indijski DrĆŸavni referalni centar za otrovanje olovom (National Referral Centre for Lead Poisoning) gdje je primila lijekove i bila upoznata s činjenicama vezanim uz otrovanje olovom. Tromjesečno je praćenje pokazalo blagi pad razina olova u krvi te značajan porast hemoglobina. Ovi se nalazi mogu pripisati promjenama u ponaĆĄanju obitelji, bez obzira na to ĆĄto je nastavila proizvoditi akumulatore

    Protection of Domestic bank Ownership in France and Germany: The Functional Equivalency of Institutional Diversity in Takeovers

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    We investigate the character of the market for corporate control (i.e. takeovers) in French and German banking. The key feature of this character is the marked ability of French and German banks to resist unsolicited takeover bids, especially – although not exclusively– those from foreign competitors. We present an institutional perspective to account for the restrained character of takeovers in French and German banking. Our perspective is composed of two elements. First, institutional arrangements are important since they structure power relations among firm stakeholders by providing opportunities, as well as imposing constraints, to influence the decision-making process in which takeover transactions take place. Second, institutional arrangements provide firm stakeholders with several potential opportunities, not just one, to block unsolicited bids since takeover contests are composed of sequences of decisions for which approval is needed at each stage. French and German banks have used different mixes of institutional arrangements, themselves located at different stages of takeover transactions, to secure restrained markets for corporate control. Our institutional analysis, in turn, also illustrates an important shortcoming of banking sector protectionism, namely the contribution of protection from unsolicited takeover bids to the building of banks carrying systemic risks

    Globalization, multinationals and institutional diversity

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    This article aims to explore the impact of globalization and in particular multinationals on diversity within national varieties of capitalism. Do the actions of multinationals create more diversity within national systems, do they reduce diversity or do they have relatively little impact on diversity within national systems? The article argues that there are distinctive structures of institutional diversity across different national systems. Therefore, the question is not how do MNCs impact on institutional diversity per se but how do they impact on these different structures of diversity? In order to develop this argument, the paper also differentiates types of multinational. The article uses distinction between market-seeking, resource-seeking, efficiency-seeking and strategic asset-seeking in order to identify a range of different MNC activity across manufacturing, professional and financial sectors. These different sorts of MNC activity vary across time and contexts in terms of their significance. The article looks in detail at four different models of capitalism and examines how the entry of different sorts of multinationals with distinctive objectives impacts on the relationships between key social actors which underpin and reinforce these models. In this way, it suggests how institutional diversity within different types of capitalism may evolve under the impact of MNCs and globalization

    Combined Effect of Dietary Cadmium and Benzo(a)pyrene on Metallothionein Induction and Apoptosis in the Liver and Kidneys of Bank Voles

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    Bank voles free living in a contaminated environment have been shown to be more sensitive to cadmium (Cd) toxicity than the rodents exposed to Cd under laboratory conditions. The objective of this study was to find out whether benzo(a)pyrene (BaP), a common environmental co-contaminant, increases Cd toxicity through inhibition of metallothionein (MT) synthesis—a low molecular weight protein that is considered to be primary intracellular component of the protective mechanism. For 6 weeks, the female bank voles were provided with diet containing Cd [less than 0.1 Όg/g (control) and 60 Όg/g dry wt.] and BaP (0, 5, and 10 Όg/g dry wt.) alone or in combination. At the end of exposure period, apoptosis and analyses of MT, Cd, and zinc (Zn) in the liver and kidneys were carried out. Dietary BaP 5 Όg/g did not affect but BaP 10 Όg/g potentiated rather than inhibited induction of hepatic and renal MT by Cd, and diminished Cd-induced apoptosis in both organs. The hepatic and renal Zn followed a pattern similar to that of MT, attaining the highest level in the Cd + BaP 10-ÎŒg/g group. These data indicate that dietary BaP attenuates rather than exacerbates Cd toxicity in bank voles, probably by potentiating MT synthesis and increasing Zn concentration in the liver and kidneys

    Correlations of Gene Expression with Blood Lead Levels in Children with Autism Compared to Typically Developing Controls

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    The objective of this study was to examine the correlation between gene expression and lead (Pb) levels in blood in children with autism (AU, n = 37) compared to typically developing controls (TD, n = 15). We postulated that, though lead levels did not differ between the groups, AU children might metabolize lead differently compared to TD children. RNA was isolated from blood and processed on Affymetrix microarrays. Separate analyses of covariance (ANCOVA) corrected for age and gender were performed for TD, AU, and all subjects (AU + TD). To reduce false positives, only genes that overlapped these three ANCOVAs were considered. Thus, 48 probe sets correlated with lead levels in both AU and TD subjects and were significantly different between the groups (p(Diagnosis × log2 Pb) < 0.05). These genes were related mainly to immune and inflammatory processes, including MHC Class II family members and CD74. A large number (n = 791) of probe sets correlated (P ≀ 0.05) with lead levels in TD but not in AU subjects; and many probe sets (n = 162) correlated (P ≀ 0.05) with lead levels in AU but not in TD subjects. Only 30 probe sets correlated (P ≀ 0.05) with lead levels in a similar manner in the AU and TD groups. These data show that AU and TD children display different associations between transcript levels and low levels of lead. We postulate that this may relate to the underlying genetic differences between the two groups, though other explanations cannot be excluded

    Nuclear localised more sulphur accumulation1 epigenetically regulates sulphur homeostasis in Arabidopsis thaliana

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    Sulphur (S) is an essential element for all living organisms. The uptake, assimilation and metabolism of S in plants are well studied. However, the regulation of S homeostasis remains largely unknown. Here, we report on the identification and characterisation of the more sulphur accumulation1 (msa1-1) mutant. The MSA1 protein is localized to the nucleus and is required for both S adenosylmethionine (SAM) production and DNA methylation. Loss of function of the nuclear localised MSA1 leads to a reduction in SAM in roots and a strong S-deficiency response even at ample S supply, causing an over- accumulation of sulphate, sulphite, cysteine and glutathione. Supplementation with SAM suppresses this high S phenotype. Furthermore, mutation of MSA1 affects genome-wide DNA methylation, including the methylation of S-deficiency responsive genes. Elevated S accumulation in msa1-1 requires the increased expression of the sulphate transporter genes SULTR1;1 and SULTR1;2 which are also differentially methylated in msa1-1. Our results suggest a novel function for MSA1 in the nucleus in regulating SAM biosynthesis and maintaining S homeostasis epigenetically via DNA methylation
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