Clinical characteristics and treatment outcomes of women with heroin dependence in Johannesburg, South Africa.

BACKGROUND: There has been a steady increase in the number of women with heroin dependence in South Africa (SA). Data from developed countries suggest that women with substance use disorder have unique treatment needs. There are limited SA data on women with heroin dependence and their response to treatment. OBJECTIVES: To describe the clinical and psychosocial characteristics of women entering inpatient rehabilitation for heroin dependence, determine the outcomes of treatment 3 and 9 months after rehabilitation, and compare these findings with male heroin users. METHODS: We conducted a longitudinal study of 44 women with heroin dependence who were admitted to a rehabilitation facility in the West Rand Municipality of Gauteng Province, SA. The participants were assessed during admission and 3 and 9 months after leaving inpatient rehabilitation. Structured interviews measured changes in drug use, psychopathology, social functioning, injecting and sexual behaviour, criminality and general health. Statistical analysis of these outcomes and comparison between women and men at 3 months and 9 months was performed by a generalised estimating equation. Fixed and time-varying covariates were included in the models. RESULTS: At baseline, 40% of female participants were HIV-positive, 50% engaged in sex work, 27% were injecting heroin users, and 75% were diagnosed with a comorbid mental illness. Thirty-seven (84%) and 30 (68%) were re-interviewed at the 3- and 9-month follow-up points, respectively. Of these, 6 were abstinent from all substances at 3 months and 2 at 9 months. Compared with males, females had a higher prevalence of HIV infection (p=0.006) and mental illness (p=0.0002) at enrolment. At 9 months, women had similar levels of drug use and criminality to men but scored significantly worse in terms of general health, social function and risky sexual behaviour. CONCLUSIONS: Women with heroin dependence in Johannesburg have high rates of HIV infection and comorbid mental illness and low rates of abstinence after inpatient detoxification and psychosocial therapy. Women fared worse than men in many domains of treatment outcome. This study builds evidence for the need for gender-sensitive substance rehabilitation facilities in SA.

Anti-HIV drugs promote ß-amyloid deposition and impair learning and memory in BALB/c mice.

OBJECTIVES: Growing evidence suggested that antiretroviral (ARV) drugs may promote amyloid beta (Aß) accumulation in HIV-1-infected brain and the persistence of HIV-associated neurocognitive disorders (HANDs). It has also been shown that lipid peroxidation upregulates ß-site amyloid precursor protein (APP) cleaving enzyme 1 (BACE1) expression and subsequently promotes Aß peptide production. In the present study, we examined whether chronic exposure to the anti-HIV drugs tenofovir disoproxil fumarate (TDF) and nevirapine induces lipid peroxidation thereby promoting BACE1 and Aß generation and consequently impair cognitive function in mice. METHODS: TDF or nevirapine was orally administered to female BALB/c mice once a day for 8 weeks. On the 7th week of treatment, spatial learning and memory were assessed using the Morris water maze test. The levels of lipid peroxidation, BACE1, amyloid ß 1-42 (Aß1-42) and Aß deposits were measured in the hippocampal tissue upon completion of treatment. RESULTS: Chronic administration of nevirapine induced spatial learning and memory impairment in the Morris water maze test, whereas TDF did not have an effect. TDF and nevirapine administration increased hippocampal lipid peroxidation and Aß1-42 concentration. Nevirapine further upregulated BACE1 expression and Aß deposits. CONCLUSION: Our results suggest that chronic exposure to TDF and nevirapine contributes to hippocampal lipid peroxidation and Aß accumulation, respectively, as well as spatial learning and memory deficits in mice even in the absence of HIV infection. These findings further support a possible link between ARV drug toxicity, Aß accumulation and the persistence of HANDs.

Modeling Patterns of Total Dissolved Solids Release from Central Appalachia, USA, Mine Spoils.

Surface mining in the central Appalachian coalfields (USA) influences water quality because the interaction of infiltrated waters and O with freshly exposed mine spoils releases elevated levels of total dissolved solids (TDS) to streams. Modeling and predicting the short- and long-term TDS release potentials of mine spoils can aid in the management of current and future mining-influenced watersheds and landscapes. In this study, the specific conductance (SC, a proxy variable for TDS) patterns of 39 mine spoils during a sequence of 40 leaching events were modeled using a five-parameter nonlinear regression. Estimated parameter values were compared to six rapid spoil assessment techniques (RSATs) to assess predictive relationships between model parameters and RSATs. Spoil leachates reached maximum values, 1108 ± 161 µS cm on average, within the first three leaching events, then declined exponentially to a breakpoint at the 16th leaching event on average. After the breakpoint, SC release remained linear, with most spoil samples exhibiting declines in SC release with successive leaching events. The SC asymptote averaged 276 ± 25 µS cm. Only three samples had SCs >500 µS cm at the end of the 40 leaching events. Model parameters varied with mine spoil rock and weathering type, and RSATs were predictive of four model parameters. Unweathered samples released higher SCs throughout the leaching period relative to weathered samples, and rock type influenced the rate of SC release. The RSATs for SC, total S, and neutralization potential may best predict certain phases of mine spoil TDS release.

Long-term Effects of Rock Type on Appalachian Coal Mine Soil Properties.

Rock-derived overburden material is used as a topsoil substitute for reclamation of Appalachian coal mines. We evaluated five mixtures ( = 4 each) of sandstone (SS) and siltstone (SiS) overburden as topsoil substitutes for 25+ years to quantify changes in mine soil properties. The study area was planted only to tall fescue [ (Schreb.)], but over 50 herbaceous species invaded over time. Standing biomass was highest in early years (5.2-9.3 Mg ha in 1983) and was strongly affected by rock type (SS > SiS), declined significantly by 1989 (1.5-2.4 Mg ha), and then increased again (2×) by 2008. However, there was no long-term rock type effect on standing biomass. Rock fragments and texture differed after 26 yr, with fewer rock fragments in the SS-dominated mixtures (53 vs. 77% in SiS) and lower sand and higher clay in the SiS-dominated mixtures. Soil pH initially ranged from 5.45 (SS) to 7.45 (SiS), dropped for several years, increased in all SiS mixes, and then slowly declined again to 5.65 (SS) to 6.46 (SiS) over the final 15 yr. Total N, organic matter, and cation exchange capacity increased with time, and extractable P decreased. Chemical weathering was most apparent initially, but physical weathering of rock fragments and changes in texture continued throughout the study period. Influences of original rock mixtures remained apparent after 25+ yr in both physical and chemical properties of these mine soils, which remained much coarser than local native soils but were higher in pH, exchangeable cations, and extractable P.

Predicting total dissolved solids release from central Appalachian coal mine spoils.

Appalachian USA surface coal mines face public and regulatory pressure to reduce total dissolved solids (TDS) in discharge waters, primarily due to effects on sensitive macroinvertebrates. Specific conductance (SC) is an accurate surrogate for TDS and relatively low levels of SC (300-500 µS cm(-1)) have been proposed as regulatory benchmarks for instream water quality. Discharge levels of TDS from regional coal mines are frequently >1000 µS cm(-1). The primary objectives of this study were to (a) determine the effect of rock type and weathering status on SC leaching potentials for a wide range of regional mine spoils; (b) to relate leachate SC from laboratory columns to actual measured discharge SC from field sites; and (c) determine effective rapid lab analyses for SC prediction of overburden materials. We correlated laboratory unsaturated column leaching results for 39 overburden materials with a range of static lab parameters such as total-S, saturated paste SC, and neutralization potential. We also compared column data with available field leaching and valley fill discharge SC data. Leachate SC is strongly related to rock type and pre-disturbance weathering. Fine-textured and non-weathered strata generally produced higher SC and pose greater TDS risk. High-S black shales produced the highest leachate SC. Lab columns generated similar range and overall SC decay response to field observations within 5-10 leaching cycles, while actual reduction in SC in the field occurs over years to decades. Initial peak SC can be reliably predicted (R(2) > 0.850; p < 0.001) by simple lab saturated paste or 1:2 spoil:water SC procedures, but predictions of longer-term SC levels are less reliable and deserve further study. Overall TDS release risk can be accurately predicted by a combination of rock type + S content, weathering extent, and simple rapid SC lab measurements.

Beneficial Use of Dredge Materials for Soil Reconstruction and Development of Dredge Screening Protocols.

Upland placement of dredge sediments has the potential to provide beneficial reuse of suitable sediments for agricultural uses or urban soil reconstruction. However, the use of many dredge materials is limited by contaminants, and most established screening protocols focus on limiting major contaminants such as heavy metals and polycyclic aromatic hydrocarbons and generally ignore fundamental agronomic parameters. Since 2001, we have placed over 450,000 m of Potomac River fresh water dredge materials and 250,000 m of saline materials from various locations into monitored confined upland facilities in Charles City, VA, and documented their conversion to agricultural uses. Groundwater and soil quality monitoring has indicated no adverse effects from material placement and outstanding agricultural productivity for the freshwater materials. Once placed, saline materials rapidly leach and ripen with quick declines in pH, electrical conductivity, and sodicity, but potentials for local groundwater impacts must be considered. Our experience to date indicates that the most important primary screening parameter is acid-base accounting (potential acidity or lime demand), which should become a mandatory analytical requirement. Our second level of acceptance screening is based on a combination of federal and state residual waste and soil screening standards and basic agronomic principles. High silt+clay and total organic C may also limit rapid use of many dredge materials due to extended dewatering times and physical limitations. This dredge material screening system separates potential upland placement candidates into three soil quality management categories (unsuitable, suitable, and clean fill) with differing monitoring requirements. Similar use of these sediments in urban soil reconstruction is also recommended.

Exposure to prenatal stress has deleterious effects on hippocampal function in a febrile seizure rat model.

Prenatal stress has been shown to result in the development of a number of neurological disorders in the offspring. Most of these disorders are a result of an altered HPA axis resulting in higher than normal glucocorticoid levels in the affected neonate. This leaves the offspring prone to immune challenges. Therefore the aim of the present study was to investigate the effects of prenatal stress and febrile seizures on behavior and hippocampal function. Pregnant dams were exposed to restraint stress during the third trimester. Following birth, febrile seizures were induced in two week old pups using lipopolysaccharide and kainic acid. A week later, anxiety-like behavior and navigational ability was assessed. Trunk blood was used to measure basal corticosterone concentration and hippocampal tissue was collected and analyzed. Our results show that exposure to prenatal stress increased basal corticosterone concentration. Exposure to prenatal stress exacerbated anxiety-like behavior and impaired the rat's navigational ability. Exposure to prenatal stress resulted in reduced hippocampal mass that was exacerbated by febrile seizures. However, exposure to febrile seizures did not affect hippocampal mass in the absence of prenatal stress. This suggests that febrile seizures are exacerbated by exposure to early life stressors and this may lead to the development of neurological symptoms associated with a malfunctioning hippocampus.

A column evaluation of Appalachian coal mine spoils' temporal leaching behavior.

Appalachian surface coal mine overburden affects water quality as drainage percolates through spoil disposal fills. This study evaluated leaching potentials of 15 spoils from south-central Appalachia. Most bulk samples were non acid-forming, all were low in total-S, (≤0.34%), and initial saturated paste specific conductance (SC) ranged from 264 to 3560 µS cm(-1). Samples were leached unsaturated (40 cycles) and leachates analyzed for pH, SC, and ion composition. Overall, leachates from unweathered spoils were higher in pH and SC than leachates from weathered spoils. Fine-textured spoils generally produced higher SCs than more coarsely textured spoils. Mean SC for all spoils decreased rapidly from an initial peak of 1468 µS cm(-1) (±150) to 247 µS cm(-1) (±23). Release patterns for most major ions reflected declining SC. Bicarbonate typically increased with successive leaches, replacing sulfate as the dominant anion. Column SC values were comparable to relevant published field data.

Parent material and vegetation influence soil microbial community structure following 30-years of rock weathering and pedogenesis.

The process of pedogenesis and the development of biological communities during primary succession begin on recently exposed mineral surfaces. Following 30 years of surface exposure of reclaimed surface mining sites (Appalachian Mountains, USA), it was hypothesized that microbial communities would differ between sandstone and siltstone parent materials and to a lesser extent between vegetation types. Microbial community composition was examined by targeting bacterial and archaeal (16S ribosomal RNA (rRNA)) and fungal (internal transcribed spacer (ITS)) genes and analyzed using Illumina sequencing. Microbial community composition significantly differed between parent materials and between plots established with tall fescue grass or pitch x loblolly pine vegetation types, suggesting that both factors are important in shaping community assembly during early pedogenesis. At the phylum level, Acidobacteria and Proteobacteria differed in relative abundance between sandstone and siltstone. The amount of the heavy fraction carbon (C) was significantly different between sandstone (2.0 mg g(-1)) and siltstone (5.2 mg g(-1)) and correlated with microbial community composition. Soil nitrogen (N) cycling was examined by determining gene copy numbers of ureC, archaeal amoA, and bacterial amoA. Gene quantities tended to be higher in siltstone compared to sandstone but did not differ by vegetation type. This was consistent with differences in extractable ammonium (NH4 (+)) concentrations between sandstone and siltstone (16.4 vs 8.5 µg NH4 (+)-N g(-1) soil), suggesting that nitrification rates may be higher in siltstone. Parent material and early vegetation are important determinants of early microbial community assembly and could be drivers for the trajectory of ecosystem development over longer time scales.

Methamphetamine reversed maternal separation-induced decrease in nerve growth factor in the ventral hippocampus.

Stress has been suggested to predispose individuals to drug abuse. The early life stress of maternal separation (MS) is known to alter the response to drugs of abuse later in life. Exposure to either stress or methamphetamine has been shown to alter neurotrophic factors in the brain. Changes in neurotrophin levels may contribute to the underlying molecular mechanisms responsible for drug use- and stress-induced behaviours. The purpose of the present study was to investigate the individual effects of MS and methamphetamine administration during adolescence and the combined effects of both stressors on brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) levels in the dorsal and ventral hippocampus (HC) in adulthood. Methamphetamine administration (1 mg/kg, daily from postnatal day (PND) 33 to 36 and from PND 39 to 42), MS and the combination of the two stressors resulted in decreased BDNF levels in both the dorsal and ventral HC. MS decreased NGF levels in the ventral HC which was restored by methamphetamine administration in adolescence. In the dorsal HC, NGF remained unaltered by either stressor alone or in combination. We propose that the restoration of NGF levels in the ventral HC may reflect a possible compensatory mechanism in response to methamphetamine exposure in adolescence following the early life stress of MS.

Artifact weathering, anthropogenic microparticles and lead contamination in urban soils at former demolition sites, Detroit, Michigan.

A chronological sequence of urban soils 3-92 years old was studied to determine the effects of time on morphogenesis, artifact weathering, and the geochemical partitioning of Pb. Key chronofunctions determined are an increase in ˆA horizon Development Index (defined herein based on soil color) and water-soluble Pb, and a decrease in pH and C/N, with increasing soil age. Key artifact weathering reactions are: 1) portlandite in mortar altered to calcite, 2) ferrite in wrought-iron altered to ferrihydrite and goethite, and 3) carbonaceous materials altered to water-soluble organic substances. Mortar and wrought-iron were found to be Pb-bearing, but weather to produce immobilizing agents. Hence, they are both a source and a sink for Pb. The origin and mobilization of water-soluble Pb is complex and probably includes microbial extracellular polymeric substances, biodegraded soil organic matter, and solubilized organic substances derived from carbonaceous anthropogenic microparticles (soot, char and coal-related wastes).

Exercise partly reverses the effect of maternal separation on hippocampal proteins in 6-hydroxydopamine-lesioned rat brain.

Animals subjected to maternal separation stress during the early stages of development display behavioural, endocrine and growth factor abnormalities that mirror the clinical findings in anxiety/depression. In addition, maternal separation has been shown to exacerbate the behavioural deficits induced by 6-hydroxydopamine (6-OHDA) in a rat model of Parkinson's disease. In contrast, voluntary exercise reduced the detrimental effects of 6-OHDA in the rat model. The beneficial effects of exercise appeared to be largely due to compensation in the non-lesioned hemisphere. The aim of the present study was to investigate whether voluntary exercise for 3 weeks could reverse the effects of maternal separation in rats challenged with the neurotoxin 6-OHDA infused into the medial forebrain bundle after 1 week of exercise, at postnatal day 60. The rats were killed 2 weeks later, at postnatal day 74. Their brains were dissected and the hippocampus rapidly removed for proteomic analysis by isobaric tagging (iTRAQ) and quantification of peptides by matrix-assisted laser desorption/ionization tandem mass spectrometry (MALDI-MS/MS). Maternal separation upregulated hippocampal proteins functionally involved in energy metabolism (nucleoside diphosphate kinase B, enolase and triosephosphate isomerase) and synaptic plasticity (α-synuclein, tenascin-R, Ba1-667, brevican and neurocan core protein) in the non-lesioned hemisphere. Exercise reversed many of these changes by downregulating the levels of hippocampal proteins functionally associated with energy metabolism (nucleoside diphosphate kinase B, enolase and triosephosphate isomerase) and synaptic plasticity (α-synuclein, tenascin-R, Ba1-667, brevican and neurocan core protein) in the non-lesioned hemisphere of rats subjected to maternal separation. Exercise and maternal separation therefore appeared to have opposing effects on the hippocampus in the non-lesioned hemisphere of the rat brain. Exercise seemed partly to reverse the effects of maternal separation stress on these proteins in the non-lesioned hemisphere. The partial reversal of maternal separation-induced proteins by exercise in the non-lesioned side sheds some insight into the mechanism by which exercise alters the molecular role players involved in determining the consequences of early life stress.

Early maternal separation leads to down-regulation of cytokine gene expression.

Exposure to stressors may lead to subsequent alterations in the immune response. The precise mechanisms underlying such vulnerability are poorly understood, but may be hypothesized to include changes in cytokine systems. Maternal separation was used as a model of exposure to early life stressors. Subsequent cytokine gene expression was studied using a cytokine gene expression array. Maternal separation resulted in significant down-regulation of the expression of 6 cytokine genes; chemokine ligand 7, chemokine receptor 4, interleukin 10, interleukin-1beta, interleukin 5 receptor alpha and integrin alpha M. Specific cytokines may be involved in mediating the effects of early adversity on subsequent immunosuppression. Further work is needed to delineate fully the relationship between early adversity, immune alterations, and behavioural changes.

The effects of lobeline and naltrexone on methamphetamine-induced place preference and striatal dopamine and serotonin levels in adolescent rats with a history of maternal separation.

Exposure to early life stress has been suggested to increase an individual's vulnerability to methamphetamine (MA) dependence. Although there is no cure for drug dependence, the opioid and vesicular monoamine transporter 2 (VMAT2) systems may be useful targets for treatment insofar as they play pivotal roles in the neurochemistry of addiction. Here we investigated the effects of naltrexone (opioid antagonist) and lobeline (VMAT2 inhibitor) on MA-induced place preference in adolescent rodents subjected to early life trauma (maternal separation, MS) and controls, as well as the effects on dopamine and serotonin levels in the striatum. We found: (1) maternal separation attenuated methamphetamine-induced place preference; (2) lobeline and naltrexone treatment had differential effects on serotonin and dopamine concentrations in the striatum, naltrexone increased serotonin levels in the maternally separated animals. The hypothesized effect of early adversity increasing MA-induced place preference may not be apparent in adolescence. However the data are consistent with the hypothesis that early life stress influences neurochemical pathways that predispose an individual to drug dependence.

Effects of maternal separation and methamphetamine exposure on protein expression in the nucleus accumbens shell and core.

Early life adversity has been suggested to predispose an individual to later drug abuse. The core and shell sub-regions of the nucleus accumbens are differentially affected by both stressors and methamphetamine. This study aimed to characterize and quantify methamphetamine-induced protein expression in the shell and core of the nucleus accumbens in animals exposed to maternal separation during early development. Isobaric tagging (iTRAQ) which enables simultaneous identification and quantification of peptides with tandem mass spectrometry (MS/MS) was used. We found that maternal separation altered more proteins involved in structure and redox regulation in the shell than in the core of the nucleus accumbens, and that maternal separation and methamphetamine had differential effects on signaling proteins in the shell and core. Compared to maternal separation or methamphetamine alone, the maternal separation/methamphetamine combination altered more proteins involved in energy metabolism, redox regulatory processes and neurotrophic proteins. Methamphetamine treatment of rats subjected to maternal separation caused a reduction of cytoskeletal proteins in the shell and altered cytoskeletal, signaling, energy metabolism and redox proteins in the core. Comparison of maternal separation/methamphetamine to methamphetamine alone resulted in decreased cytoskeletal proteins in both the shell and core and increased neurotrophic proteins in the core. This study confirms that both early life stress and methamphetamine differentially affect the shell and core of the nucleus accumbens and demonstrates that the combination of early life adversity and later methamphetamine use results in more proteins being affected in the nucleus accumbens than either treatment alone.

Transformations of nitrogen and carbon in entrenched biosolids at a reclaimed mineral sands mining site.

Biosolids deep-row incorporation (DRI) provides high levels of nutrients to the reclamation sites; however, additions of N in excess of the vegetation requirements can potentially impair water quality. The effects of anaerobically digested (AD) and lime stabilized (LS) DRI biosolids and inorganic N fertilizer were compared on C and N transformations and transport at a reclaimed mineral sands mining site. Biosolids were applied at 213 and 426 Mg AD biosolids ha(-1) and 328 and 656 Mg LS biosolids ha)(-1) (dry mass), and inorganic N fertilizer was applied at 0 (control) and 504 kg N ha-(-1) yr(-1). Zero tension lysimeters were installed to collect leachate for determination of vertical N transport, and the biosolids seams were analyzed for N and C transformations after 28 mo aging. The leachijng masses from the DRI biosolids treatments were 139 to 291 kg ha(-1) NO3-N, 61 to 243 kg ha(-1) NH4-N, and 61 to 269 kg ha(-1) organic N, while the fertilizer treatment did not differ from the control. Aged biosolids analysis showed that total N lost over the course of 2 yr was 15.2 Mg ha(-1) and 10.9 Mg ha(-1) for LS and AD biosolids, respectively, which was roughly 50% of the N applied. Organic C losses were 81 Mg ha(-1) and 33 Mg ha(-1) for LS and AD biosolids, respectively. Our results indicated that entrenchment of biosolids in coarse-textured media should not be used as a mined land reclamation technique because the anaerobic conditions required to limit mineralization and nitrification cannot be maintained in such permeable soils.

Chemistry and transport of metals from entrenched biosolids at a reclaimed mineral sands mining site.

Deep row incorporation of biosolids is an alternative land treatment method whose typically high rates may result in elevated pollutant transport. The objectives of this research were to compare the effects of entrenched biosolids stabilization type and rate on heavy metal chemistry and mobility. Two rates each of Alexandria (Virginia) Sanitation Authority anaerobically digested (213 and 426 dry Mg ha(-1)) and Blue Plains (Washington, DC) lime-stabilized (329 and 657 dry Mg ha(-1)) biosolids were placed in trenches at a mineral sands mine reclamation site in Dinwiddie County, Virginia, in summer 2006. Vertical and lateral transport of heavy metals from the biosolids seams were determined by analyzing leachate collected in zero tension lysimeters below the trenches and suction lysimeters adjacent to the trenches. Silver, Cd, Pb, and Sn did not move vertically or laterally to any significant extent. During the 15-mo period following entrenching, lime-stabilized biosolids produced higher cumulative metal mass transport for Cu (967 g ha(-1)), Ni (171 g ha(-1)), and Zn (1027 g ha(-1)) than did the anaerobically digested biosolids and control. Barium mass loss was similar for both biosolids. All metals moved primarily with particulates. MINTEQA) predicted that > 70% of Cu was bound to fulvic acids, whereas > 80% of Ba was found as Ba2+. As pH decreased with time, free ions of Zn decreased and the metal's association with fulvic acids increased. Largely insignificant transport of metals into the lysimeters demonstrated that biosolids-borne heavy metals posed little risk to groundwater even when entrenched in very coarse-textured soil.

Phytoavailability of cadmium in long-term biosolids-amended soils.

Agronomic use of biosolids has raised concern that plant availability of biosolids-Cd will increase with time after cessation of biosolids application. It has been demonstrated that chemical extractability of Cd is persistently decreased in biosolids-amended soils. This study was conducted to determine if Cd phytoavailability in long-term biosolids-amended soils was also persistently decreased. Paired control and biosolids-amended soils were collected from three experimental sites where large cumulative rates of biosolids were applied about 20 yr ago. The pH of all soils [in 0.01 mol L(-1) Ca(NO(3))(2)] was adjusted to 6.5 +/- 0.2. Increasing rates of Cd-nitrate (from 0 to 10.0 mg Cd kg(-1) soil) enriched in (111)Cd stable isotope were added to all soils, and Romaine lettuce (Lactuca sativa L. var. longifolia Lam.) was grown in pots to bioassay phytoavailable Cd. After harvest, Cd concentrations in shoots and labile pool of Cd (Cd(L)) in soils were determined. The relationship between added salt-Cd and Cd concentrations in lettuce shoots was linear for all soils tested. Ratios of (shoot Cd):(soil Cd) slopes were highest in the control soils. Biosolids amendment decreased (shoot Cd):(soil Cd) slopes to varied extent depending on biosolids source, properties, and application rate. The decrease in slope in comparison to the control was an indication of the lower phytoavailability of Cd in biosolids-amended soils. A significant negative correlation existed between Cd uptake slopes and soil organic matter, free and amorphous Fe and Al oxides, Bray-P, and soil and plant Zn. Biosolids-Cd was highly labile (%L 80-95) except for Fulton County soil (%L = 61).

Maternal separation alters nerve growth factor and corticosterone levels but not the DNA methylation status of the exon 1(7) glucocorticoid receptor promoter region.

Separating rat pups from their mothers during the early stages of life is an animal model commonly used to study the development of psychiatric disorders such as anxiety and depression. The present study investigated how soon after the termination of the maternal separation period behavioural and neuroendocrine abnormalities relevant to above-mentioned illnesses would manifest. Sprague Dawley rat pups were subjected to maternal separation (3 h per day from postnatal day 2 through 14) and their behaviour and HPA axis activity determined 7 d later. We also measured nerve growth factor levels in their hippocampi and assessed the DNA methylation status of the promoter region of exon 1(7) of the glucocorticoid receptor in this brain region. As early as 7 d after the termination of the adverse event, a change in behaviour was observed that was associated with increased plasma corticosterone release and elevated nerve growth factor levels in the hippocampus. No alteration in the methylation status of the exon 1(7) glucocorticoid receptor promoter region was observed. Our data indicate that early life adversity may lead to the rapid development of abnormal behaviours and HPA axis dysregulation though no epigenetic changes to the exon 1(7) glucocorticoid receptor promoter region occurred. We further propose that the observed increased neurotrophin levels reflect compensatory mechanisms that attempt to combat the long-term deleterious effects of maternal separation.