Serum 25-hydroxy vitamin D levels in essential hypertension.

Vitamin D may have prognostic value in hypertension patients and, in addition to conventional biomarkers, could be a valuable tool for disease management. The aim of this study was to assess the association of vitamin D status in patients with essential hypertension and to evaluate its prognostic utility. Forty-eight consecutive patients (40 Caucasian and 8 Asian) aged between 30 and 80 years (mean 61.5, range 34-84 years), were enrolled in the study. The main exclusion criteria were age less than 18 years, kidney failure, onco-hematologic disease, hypo-hyperparathyroidism, osteoporosis, treatment with bisphosphonate or 25(OH) vitamin D supplementation. Of the 48 patients included in the study, hyperlipidemia was described in 28, diabetes type 2 in 8, and ischemic heart disease in 14. Serum electrolytes, calcium, sodium, and potassium concentrations were within normal range. Low 25(OH) vitamin D levels inversely correlated with essential hypertension values (p less than 0.001) were considered extremely significant. The determination of 25(OH) vitamin D levels in patients with essential hypertension could improve the research for possible underlying conditions, which should be managed meticulously according to current guidelines.

Magnetic resonance imaging and pathological features of a mixed glioma in a dog: case report / Aspectos patológicos e das imagens de ressonância magnética de um glioma misto em um cão: relato de caso

The aim of this report was to describe the magnetic resonance imaging (MRI) and pathological features of a canine mixed glioma. A 12-year-old boxer male dog was presented for necropsy along with data from an MRI evaluation conducted ante-mortem. The images were examined and showed a poorly demarcated prosencephalic lesion, hyperintense on T2W images, hypointense on T1W images and heterogeneously hyperintense on T2W FLAIR images. There was mild nonuniform contrast enhancement, apparent midline shift, moderate perilesional edema and marked distortion of the adjacent lateral ventricle. The brain was evaluated macroscopically, microscopically and immunohistochemically. Grossly, there was a poorly demarcated soft mass, with areas of hemorrhage, within the left parietal and temporal lobes. Histologically, there was a densely cellular mass composed of two geographically distinct populations of neoplastic cells. The first population was composed of small and round cells organized in a honeycomb pattern. The second population constituted of intermingled streams and bundles of neoplastic cells that were strongly immunolabeled for glial fibrillary acidic protein (GFAP). The diagnosis of a mixed glioma was based on MRI findings, and mainly on histological and immunohistochemical findings.(AU)

O objetivo deste relato foi descrever as características patológicas e das imagens de ressonância magnética de um glioma misto canino. Um cão de 12 anos de idade da raça Boxer foi submetido à necropsia. As imagens obtidas ante mortem por ressonância magnética foram analisadas, e nelas se observou uma lesão prosencefálica com contornos pouco definidos, sinal hiperintenso nas imagens ponderadas em T2, hipointenso nas imagens ponderadas em T1, e heterogeneamente hiperintenso em T2-FLAIR. Havia discreto realce desuniforme ao contraste, evidente desvio da linha média, edema perilesional moderado e marcada distorção do ventrículo lateral adjacente. O encéfalo foi avaliado macroscopicamente, microscopicamente e imuno-histoquimicamente. Macroscopicamente, havia uma massa pobremente demarcada, com áreas de hemorragia, nos lobos parietal e temporal esquerdos. Histologicamente, havia uma massa densamente celular, composta por duas populações de células neoplásicas distintas separadas geograficamente. A primeira população era composta por células pequenas e redondas, organizadas com aspecto de favo de mel. A segunda população era constituída por feixes entrelaçados de células neoplásicas fortemente imunomarcadas para a proteína fibrilar ácida glial (GFAP). O diagnóstico de glioma misto foi obtido com base nos achados imaginológicos e, principalmente, em suas características histológicas e imuno-histoquímicas.(AU)

Serum 25-hydroxy vitamin D concentration in acute coronary syndrome.

Vitamin D may have prognostic value in cardiovascular disease (CVD) patients and, in addition to conventional biomarkers, could be a valuable tool for disease management. The aim of this study was to assess the association of vitamin D status in patients with acute coronary syndrome (ACS) and to evaluate its prognostic utility. The levels of 25(OH) vitamin D were correlated with troponin T hs. Forty-eight consecutive outpatients (40 Caucasian and 8 Asian) aged between 40 and 70 years (mean 61.5, range 43-77 years) were enrolled in the study. All patients were admitted to the Emergency Department with chest pain and suspected ACS. The main exclusion criteria were age <18 years, kidney failure, onco-haematological disease, hypo-hyperparathyroidism, hypo/hyperthyroidism, osteoporosis, treatment with bisphosphonate or 25(OH) vitamin D supplementation. Of the 48 subjects included in the study, thoracic pain symptoms were described in 12 patients with unstable angina (UA) and in 6 patients with ST elevation myocardial infarction (STEMI) and in 30 patients with non-ST-elevation myocardial infarction (NSTEMI). Low 25(OH) vitamin D levels correlated with the presence of ACS (p< 0.02) and inversely correlated with Troponin T hs (TnT hs) levels (p< 0.03). The determination of 25(OH) vitamin D levels in combination with TnT hs could improve the research for possible underlying conditions, and these should be managed meticulously according to current guidelines.

Assessment of plant availability and environmental risk of biosolids-phosphorus in a U.S. Midwest Corn-Belt Soil.

A field experiment was conducted from 2005 to 2008 in Fulton County, Western Illinois with biosolids from conventional wastewater treatment applied as corn fertilizer in a series of P rates (0, 163, 325, 488, 650 kg P ha(-1)) along with commercial P fertilizer - triple superphosphate P (TSP) as reference to assess biosolids-P plant availability and potential loss to waterbodies through runoff. Air-dried biosolids and TSP were incorporated into surface soil at end of 2005, and corn (Zea mays) was planted for three consecutive years (2006-2008). Concentrations of soil extractable P except for Mehlich-3 P were always lower in the biosolids than TSP treatments at the same P rates. The soil potentially available P in water extractable P (WEP) and Olsen P derived from biosolids-P estimated by the exponential depletion model was 2-4% and 15-24% of total P in the applied biosolids, respectively. The residence time of biosolids-induced WEP and Olsen P in Midwest soil under annual corn cropping was 5 and 2 years, respectively. Corn tissue analysis showed lower increase in P concentration by biosolids-P than TSP. The elevation rate of soluble reactive P (SRP) concentration in simulated runoff was less by biosolids than TSP. Based on the data in this study, the plant availability and environmental risk of biosolids-P are lower than those of TSP in the Midwest soil, thus use of biosolids as P nutrient for corn would not cause a major impairment to water sources even P applied through biosolids was not completely used by annual crop.

Restoring Ecosystem Function in Degraded Urban Soil Using Biosolids, Biosolids Blend, and Compost.

Many soils at former industrial sites are degraded. The objective of this research was to determine the ability of compost, biosolids, and biosolids blends to improve soil ecosystem function with minimal potential impact to surface water. Treatments rototilled into the top 12.5 cm of soil were biosolids at 202 Mg ha; biosolids at 404 Mg ha; compost at 137 Mg ha; or a blend consisting of biosolids applied at 202 Mg ha, drinking water treatment residual, and biochar. Rainfall runoff from experimental plots was collected for 3 yr. One year after soil amendments were incorporated, a native seed mix containing grasses, legumes, and forbs was planted. Soil amendments improved soil quality and nutrient pools, established a dense and high-quality vegetative cover, and improved earthworm reproductive measures. Amendments increased soil enzymatic activities that support soil function. Biosolids treatments increased the Shannon-Weaver Diversity Index for grasses. For the forbs group, control plots had the lowest diversity index and the biosolids blend had the highest diversity index. Biosolids and compost increased the number of earthworm juveniles. In general, biosolids outperformed compost. Biosolids increased N and P in rainfall runoff more than compost before vegetation was established. Several microconstituents (i.e., pharmaceutical and personal care products) were detected in runoff water but at concentrations below the probable no-effect levels and therefore should pose little impact to the aquatic environment. Future restoration design should ensure that runoff control measures are used to control sediment loss from the restored sites at least until vegetation is established.

Assessing the association between 25-OH vitamin D levels and ROMA score in a population of obese women.

The “Risk of Malignancy Algorithm” (ROMA) combines the diagnostic power of the CA125 and HE4 markers with menopausal status to predict the risk for developing epithelial ovarian cancer (EOC). The aim of this study was to evaluate the association between 25-OH vitamin D levels and ROMA score in obese women. One hundred and eighteen patients with a Body Mass Index (BMI) > 30 kg/m2 (Group 1) and 80 women with a BMI less than 25 kg / m² (Group 2) were studied. The 25-OH vitamin D was quantified with LUMIPULSE® G 1200. As a threshold value, identified by ROC curve analysis, 20.2 ng/ mL (sensitivity 73.3%, specificity 84%) was chosen corresponding to the limit between sufficient and insufficient 25-OH vitamin D according to the World Health Organization (WHO). Low 25-OH vitamin D levels were observed in 64% of obese women and in 11% of normal-weight women (p less than 0.001). ROMA score above 13% was detected only in obese women (19%). An association between low levels of 25-OH vitamin D and ROMA score was observed. Indeed, 64% of obese women with ROMA score >13% had concomitant insufficient levels of 25-OH vitamin D, while only 36% of obese women with ROMA score >13% had sufficient 25-OH vitamin D levels (p less than 0.0001). This study suggests that the deficiency of 25- OH vitamin D in obese women has a possible correlation with high ROMA score.

Microbial risk assessment for recreational use of the Chicago area waterway system.

A microbial risk assessment was conducted to estimate the human health risks from incidental contact recreational activities such as canoeing, boating and fishing in the Chicago Area Waterway System (CAWS) receiving secondary treated, but non-disinfected, effluent from three municipal water reclamation plants. Actual concentrations of the pathogens (pathogenic E. coli [estimated], Giardia, Cryptosporidium, adenovirus, norovirus, enteric virus) detected from the waterway field data collection at locations upstream and downstream of the effluent outfall during dry and wet weather conditions within the recreation season were included in the risk assessment. The results under the current treatment scheme with no disinfection indicated that the total expected gastrointestinal illness (GI) rate per 1000 incidental contact recreational exposure events during combined weather (dry and wet) conditions ranged from 0.10 to 2.78 in the CAWS, which is below the eight illnesses per 1000 swimmers considered tolerable by the United States Environmental Protection Agency. Wet weather conditions contribute to elevated pathogen load to the CAWS; therefore this study determined that disinfecting the effluents of three major WRPs that discharge to the CAWS would result in an extremely small reduction in the aggregate recreation season risk to incidental contact recreators.

Dry and wet weather microbial characterization of the Chicago area waterway system.

The Chicago Area Waterway System (CAWS) is a man-made channel, which serves the Chicago area for the drainage of urban storm water and the conveyance of secondary treated effluent from the Metropolitan Water Reclamation District of Greater Chicago's (District) North Side, Stickney and Calumet water reclamation plants (WRPs). A microbial characterization of the CAWS upstream and downstream of the WRPs and from the WRP outfall was initiated by collecting dry and wet weather samples and analyzing for indicators and pathogens. During dry weather, indicator bacteria (fecal coliform [FC], E. coli [EC], enterococci [EN]) were the most abundant microbial species detected in the CAWS compared to pathogens (Salmonella spp [SA], enteric viruses [EV], adenovirus [AV], norovirus [NV] and Giardia and Cryptosporidium). Pseudomonas aeruginosa [PA] levels in the outfall samples were either lower or equivalent to the CAWS. The wet weather samples had a higher frequency of detection of indicator bacteria and pathogens compared to dry weather samples. Overall, the concentrations of pathogens in the CAWS, representing the weather conditions experienced in a recreational year, were relatively low. The study concluded that the presence of pathogens in the CAWS downstream of the WRPs were due to secondary loading of the waterway under wet weather conditions from combined sewer overflows (CSOs) and other discharges.

Antibiotic resistant bacteria in wastewater processed by the Metropolitan Water Reclamation District of Greater Chicago system.

The Metropolitan Water Reclamation District of Greater Chicago (District) initiated a research study to determine the total numbers and percentages of antibiotic resistant fecal coliform (FC) bacteria in raw sewage (RS) entering and final effluents (FE) discharged from its seven Water Reclamation Plants (WRPs). The density of FC was determined on m-FC agar containing ampicillin (ampR-16 microg/ml), gentamycin (genR-8 microg/ml), tetracycline (tetR-8 microg/ml), or all three antibiotics. The study was primarily undertaken to determine whether secondary sewage treatment at the District WRPs adequately reduces the numbers and percentages of FC(ampR), FC(tetR), FC(genR), FC(amp/tet/genR) in the FE. The numbers of ampR, tetR, genR, and amp/tet/genR FC observed in RS ranged from 2.0 x 10(5) to 1.1 x 10(7), 9.5 x 10(4) to 2.2 x 10(6), 95 to 1.5 x 10(4) and 90 to 9.5 x 10(3) per 100 mL, respectively. Secondary sewage treatment without disinfection was shown to reduce the number of antibiotic resistant FC by two-three orders of magnitude. The numbers of FC(ampR), FC(tetR), FC(genR), and FC(amp/tet/genR) observed in non-disinfected FE ranged from 2.0 x 10(2) to 6.4 x 10(3), 2.2 x 10(2) to 4.1 x 10(3), 9 to <20 and 9 to <20 per 100 mL, respectively. The relative percentages of antibiotic resistant FC observed in FE followed the same trend observed in RS: FC(ampR) > FC(tetR) > FC(genR) > FC(amp/tet/genR). Only one FC(amp/tet/genR) bacteria was found in this study indicating that multiple-antibiotic resistant FC was virtually eliminated by secondary sewage treatment. The results of multivariate regression analysis showed that the percentages of antibiotic resistant FC in the FE from all seven District WRPs were lower than the percentages of these organisms in RS (p<0.01). These results support the conclusion that secondary sewage treatment in the District effectively reduces the number of antibiotic resistant FC and that the environments of the District's seven WRPs are not conducive to the propagation or survival of antibiotic resistant fecal coliform bacteria.

Soil carbon sequestration resulting from long-term application of biosolids for land reclamation.

Investigations on the impact of application of biosolids for land reclamation on C sequestration in soil were conducted at Fulton County, Illinois, where 41 fields (3.6-66 ha) received biosolids at a cumulative loading rate from 455 to 1654 dry Mg ha(-1) for 8 to 23 yr in rotation from 1972 to 2004. The fields were cropped with corn, wheat, and sorghum and also with soybean and grass or fallowed. Soil organic carbon (SOC) increased rapidly with the application of biosolids, whereas it fluctuated slightly in fertilizer controls. The peak SOC in the 0- to 15-cm depth of biosolids-amended fields ranged from 4 to 7% and was greater at higher rates of biosolids. In fields where biosolids application ceased for 22 yr, SOC was still much higher than the initial levels. Over the 34-yr reclamation, the mean net soil C sequestration was 1.73 (0.54-3.05) Mg C ha(-1) yr(-1) in biosolids-amended fields as compared with -0.07 to 0.17 Mg C ha(-1) yr(-1) in fertilizer controls, demonstrating a high potential of soil C sequestration by the land application of biosolids. Soil C sequestration was significantly correlated with the biosolids application rate, and the equation can be expressed as y = 0.064x - 0.11, in which y is the annual net soil C sequestration (Mg C ha(-1) yr(-1)), and x is annual biosolids application in dry weight (Mg ha(-1) yr(-1)). Our results indicate that biosolids applications can turn Midwest Corn Belt soils from current C-neutral to C-sink. A method for calculating SOC stock under conditions in which surface soil layer depth and mass changes is also described.

Effect of long-term application of biosolids for land reclamation on surface water chemistry.

Biosolids are known to have a potential to restore degraded land, but the long-term impacts of this practice on the environment, including water quality, still need to be evaluated. The surface water chemistry (NO3-, NH4+, and total P, Cd, Cu, and Hg) was monitored for 31 yr from 1972 to 2002 in a 6000-ha watershed at Fulton County, Illinois, where the Metropolitan Water Reclamation District of Greater Chicago was restoring the productivity of strip-mined land using biosolids. The mean cumulative loading rates during the past 31 yr were 875 dry Mg ha(-1) for 1120-ha fields in the biosolids-amended watershed and 4.3 dry Mg ha(-1) for the 670-ha fields in the control watershed. Biosolids were injected into mine spoil fields as liquid fertilizer from 1972 to 1985, and incorporated as dewatered cake from 1980 to 1996 and air-dried solids from 1987 to 2002. The mean annual loadings of nutrients and trace elements from biosolids in 1 ha were 735 kg N, 530 kg P, 4.5 kg Cd, 30.7 kg Cu, and 0.11 kg Hg in the fields of the biosolids-amended watershed, and negligible in the fields of the control watershed. Sampling of surface water was conducted monthly in the 1970s, and three times per year in the 1980s and 1990s. The water samples were collected from 12 reservoirs and 2 creeks receiving drainage from the fields in the control watershed, and 8 reservoirs and 4 creeks associated with the fields in the biosolids-amended watershed for the analysis of NO3- -N (including NO2- N), NH4+-N, and total P, Cd, Cu, and Hg. Compared to the control (0.18 mg L(-1)), surface water NO3- -N in the biosolids-amended watershed (2.23 mg L(-1)) was consistently higher; however, it was still below the Illinois limit of 10 mg L(-1) for public and food-processing water supplies. Biosolids applications had a significant effect on mean concentrations of ammonium N (0.11 mg L(-1) for control and 0.24 mg L(-1) for biosolids) and total P (0.10 mg L(-1) for control and 0.16 mg L(-1) for biosolids) in surface water. Application of biosolids did not increase the concentrations of Cd and Hg in surface water. The elevation of Cu in surface water with biosolids application only occurred in some years of the first decade, when land-applied sludges contained high concentrations of trace metals, including Cu. In fact, following the promulgation of 40 CFR Part 503, the concentrations of all three metals fell below the method detection level (MDL) in surface water for nearly all samplings. Nitrate in the surface water tends to be higher in spring, and ammonium, total P, and total Hg in summer and fall. Mean nitrate, ammonium, and total phosphorus concentrations were found to be greater in creeks than reservoirs. The results indicate that application of biosolids for land reclamation at high loading rates from 1972 to 2002, with adequate runoff and soil erosion control, had only a minor impact on surface water quality.

Central cardiovascular responses induced by interleukin 1 beta and tumor necrosis factor alpha infused into nucleus tractus solitarii, nucleus parabrachialis medialis and third cerebral ventricle of normotensive rats.

The effect of IL-1 beta and TNF alpha infused into nucleus tractus solitari (NTS), nucleus parabrachialis medialis (NPBmed) and third cerebral ventricle of normotensive rats on blood pressure (BP) and heart rate (HR) was investigated. Microinfusion of IL-1 beta and TNF alpha into the third cerebral ventricle and NPBmed of normotensive rats produced a dose-dependent hypotensive and bradycardic response. A similar cardiovascular response was produced by infusion of IL1 beta into NTS but not by TNF alpha. When rats were pre-treated with Escherichia coli lipopolisaccharide (LPS), an enhancement of cardiovascular response elicited by IL-1 beta and TNF alpha was found. Thus, IL-1 beta and TNF alpha produce cardiovascular responses when infused into specific areas of the CNS. This effect is potentiated by LPS and this may explain the alteration in cardiovascular regulation which can be observed in diseases in which an excess of circulating endotoxins and cytokines may occur.

Bioavailability of biosolids molybdenum to soybean grain.

Legumes grown in biosolids-amended soils and then fed to ruminants can represent problematic sources of molybdenum (Mo), but few field data are available to quantify the risk. We used a set of fields amended to high cumulative biosolids Mo loads (>18 kg ha(-1)) over 27 yr to generate additional data. Soybean [Glycine max (L.) Merr.] was grown on 29 fields (pH values>6.8) amended to a wide range of soil Mo loads. Soybean grain harvested from each field was analyzed for Mo and the concentrations regressed against soil Mo loads estimated from actual soil Mo concentrations in the 0- to 15-cm depth. Slopes of such linear regressions represent uptake coefficients (UC values) used by the USEPA to assess risk of biosolids Mo to ruminants fed forage grown on biosolids-amended land. The UC value for all 29 fields was estimated as 1.66, which agrees with the few soybean grain data in the literature. The UC value, however, is well below a conservative UC value of 4, recently recommended for all fresh legume materials fed to cattle. Soybean grain can contain high concentrations of Mo (>10 mg kg(-1)) and have low (<2:1) Cu to Mo ratios, which can exacerbate molybdenosis problems in cattle. However, soybean grain normally constitutes only -10% of dairy cattle diet, and other constituents (e.g., corn grain, stover, mineral supplements) are sufficient, or can be manipulated, to control molybdenosis.

Bioavailability of biosolids molybdenum to corn.

This study was part of a larger effort to generate field data appropriate to the assessment of biosolids molybdenum (Mo) risk to ruminants. Corn (Zea mays L.) is an important component of cattle diet, and is a logical crop for biosolids amendment owing to its high N requirement. Paired soil and corn stover samples archived from two unique field experiments were analyzed to quantify the relationship (uptake coefficient, UC) between stover Mo and soil Mo load. Both studies used biosolids with total Mo concentrations typical of modern materials. Data from long-term (continuous corn) plots in Fulton County, IL confirm expected low Mo accumulation by corn stover, even at very high biosolids loads and soil Mo loads estimated to be near 18 kg Mo ha(-1). Uptake slopes were actually negative, but USEPA protocol would assign UC values of 0.001. Data from plots in Minnesota also suggested essentially no correlations between stover Mo and soil Mo loads for continuous corn. However, greater Mo accumulation in corn grown following soybean [Glycine max (L.) Merr.] suggests the possibility of enhanced Mo bioavailability to corn in corn-soybean rotations. Nevertheless, molybdenosis risk to cattle consuming corn stover produced on biosolids-amended land is small as stover Mo concentrations were always low and stover Cu to Mo ratios exceeded 2:1, which avoids molybdenosis problems.

Prevalence of cerebral palsy in north-east Italy from 1965 to 1989.

This study examines the prevalence of cerebral palsy (CP) in two north-east Italian provinces, Padua and Rovigo (overall population 1030 000). Six-hundred and ten children with a diagnosis of CP (330 male, 280 female), born between 1965 and 1989, were studied. The prevalence of CP progressively increased from the 1960s to the mid-1980s, and then decreased in the 5-year period, 1985 to 1989. These quantitative changes were associated with qualitative ones. For example, the number of low-birthweight (LBW) infants progressively increased, similar to results of epidemiological studies from other European countries. The clinical features of the types of CP in this study (hemiplegia, diplegia, ataxic diplegia, quadriplegia, pure ataxia, dyskinesia) generally correspond with those described in other studies. However, the prevalence of quadriplegia in this study is higher. The prevalence of types of CP related to preterm birth, such as diplegia, increased over the years, while those associated with term babies, such as dyskinesia, decreased. This study suggests that prenatal factors are associated with some types of CP, while in others, such as diplegia, quadriplegia, and dyskinesia, the perinatal factors are notable. Perinatal factors were associated with LBW children, while prenatal factors were greater for normal-birthweight infants. The variation in the prevalence of CP over the years, with two peaks corresponding with the introduction of neonatal intensive care units in Padua and Rovigo, suggests that changes in neonatal care could influence the levels of CP, independent of the original presence of predisposing prenatal factors.

Sound-evoked electrocortical desynchronization is inhibited by N omega-nitro-L-arginine methyl ester microinfused into the inferior colliculi in rats.

In previous experiments we have shown that systemic or intracerebroventricular administration of N omega-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide (NO) synthase, is able to significantly reduce sound-evoked electrocortical (ECoG) desynchronization in rats. The present experiments were aimed at identifying the site(s) of the brain through which these effects are mediated. L-NAME (200 and 300 nmol), oxyhaemoglobin (200 and 300 nmol), a NO-trapping agent, and methylene blue (100 and 150 nmol), an inhibitor of guanylate cyclase and NO synthase, given bilaterally into the inferior colliculi, but not in other relay stations of the acoustic pathway, prevented the reduction in ECoG amplitude induced by sound stimulation in rats. Significant reduction of sound-evoked ECoG desynchronization has also been observed in rats receiving injection of CGP37849 (125 and 500 pmol) and LY274614 (125 pmol), two competitive N-methyl-D-aspartate receptor antagonists into the inferior colliculi. The present results show that the inferior colliculus represents the main site where sound-evoked ECoG desynchronization is prevented by L-NAME and provide further support for the hypothesis that NO may play a role at this level in the control of the measured response.

Systemic administration of pramiracetam increases nitric oxide synthase activity in the cerebral cortex of the rat.

The effect of systemic administration of pramiracetam on neuronal type nitric oxide synthase (NOS) activity and NOS mRNA expression were studied in the hippocampus and cerebral cortex in rats. A dose of 300 mg/kg (i.p.) of this nootropic produced an approximately 20% increase in NOS activity in rat brain cortical homogenates but not in hippocampal homogenates; no significant changes were observed in NOS mRNA expression in the cortex and hippocampus. A lower dose of pramiracetam (100 mg/kg i.p.) was ineffective on NOS mRNA expression and enzyme activity. Interestingly, administration of pramiracetam (300 mg/kg i.p.) in rats pretreated (24 h before) with lithium chloride (LiCl) (3 mEq/kg i.p.) yielded a 40% increase in cortical NOS activity. However, in LiCl-pretreated rats this nootropic failed to affect cortical NOS mRNA expression; LiCl (3 mEq/kg i.p.) given alone produced no effect. In conclusion, the present data demonstrate that pramiracetam given alone or in combination with LiCl increases NOS activity in brain cortical homogenates of rats and this may contribute to the mechanisms underlying learning and memory improvement produced by this nootropic.

Lack of involvement of nitric oxide in the mechanisms of seizures and hippocampal damage produced by kainate and ouabain in rats.

The gross behavioural, electrocortical and neuropathological effects of kainate (10 mg/kg i.p,) and ouabain (1 micrograms, given into one dorsal hippocampus) were studied in rats. The effects of these treatments on nitric oxide synthase (NOS) activity in homogenates of hippocampus and cortex were also studied. Administration of kainate or ouabain produced motor and electrocortical seizures similar for latency to onset (approximately 15 min) and intensity (in all instances 80-100% of the treated rats showed behavioural and electrographic seizures). These effects were accompanied at 24 h by severe damage to all subsectors of the hippocampal formation and this concerned a similar proportion of the treated rats (n = 4-8 per treatment). No significant changes in nitric oxide synthase (NOS) activity were noted in the cerebral cortex and hippocampus of rats receiving injections of kainate and ouabain. In addition, pretreatment with N omega-Nitro-L-arginine methyl ester (300 micrograms, given into one lateral cerebral ventricle 15 min previously) was ineffective in preventing the effects of kainate and ouabain. In conclusion, present data suggest that excessive production of NO is not involved in the mechanisms triggering seizures and neurodegeneration produced by kainate or ouabain.

Plant Uptake of PCBs and Other Organic Contaminants from Sludge-Treated Coal Refuse.

A field study of industrial organic contaminant uptake, in particular PCB uptake, by growing crops was conducted during 1990 at the St. David Coal Refuse Pile Reclamation Site, Fulton County, Illinois. The site had received one-time applications in 1987 of 785, 1570 and 3360 Mg ha-1 dry wt. of Chicago municipal sewage sludge. Corn (Zea mays L.), cabbage (Brassica oleracea capitata L.), and carrot (Daucus carota L.) were grown on the sludge treatments and soil (i.e., sludge treated coal refuse) and plant samples were analyzed. Mean PCB concentratious in the soils were ≤4 mg kg-1 dry wt. and there was no consistent effect on them of sludge application rate. Measurements on the 3360 Mg ha-1 dry wt. of sludge treatment soil indicated that several organochlorine pesticides occurred at concentrations ≤217 µg kg-1 dry wt. and several polynuclear aromatic hydrocarbons occurred at <1 to 3 mg kg-1 dry wt. Mean PCB concentrations in the plant materials were <300 µg kg-1 dry wt., however, there were differences among and within crops. Concentrations decreased in the order: carrot peels > carrot tops > cabbage wrapper and inner leaves > carrot core > corn ear leaf and stover > corn grain. There was insignificant PCB in corn grain. Except for cabbage wrapper leaves, the PCB concentrations in plant materials were not related to those in soil. Soil PCB concentrations accounted for 24% of the variance in cabbage wrapper leaf PCB concentrations and the bioconcentration factor (mg PCB kg-1 dry wt. of leaf/kg PCB ha-1 dry wt. of soil) was 0.0042. There was no detection of organochlorine pesticides in plant materials grown on the 3360 Mg ha-1 dry wt. of sludge treatment soil and, except for indole and isophorone, only trace amounts of a very few other organic contaminants were observed in the plant materials. Indole ranging from no detection to 52 mg kg-1 dry wt. may have been a natural constituent of cabbage. Isophorone ranging from 14 to 79 mg kg-1 dry wt. was observed in three samples of cabbage wrapper leaves and its source is unknown. Despite the very large rates of Chicago sludge employed in this study, findings indicated that they did not (i) result in high levels of organic contamination in the treated coal refuse, and (ii) represent a significant organic contaminant hazard to the quality for food and feedstuffs of crops grown on the treated coal refuse.

Proliferation of maize (Zea mays L.) roots in response to localized supply of nitrate.

Maize (Zea mays L.) plants with two primary nodal root axes were grown for 8 d in flowing nutrient culture with each axis independently supplied with NO3-. Dry matter accumulation by roots was similar whether 1.0 mol m-3 NO3- was supplied to one or both axes. When NO3- was supplied to only one axis, however, accumulation of dry matter within the root system was significantly greater in the axis supplied with NO3-. The increased dry matter accumulation by the +N-treated axis was attributable entirely to increased density and growth of lateral branches and not to a difference in growth of the primary axis. Proliferation of lateral branches for the +N axis was associated with the capacity for in situ reduction and utilization of a portion of the absorbed NO3-, especially in the apical region where lateral primordia are initiated. Although reduced nitrogen was translocated to the -N axis, concentrations in the -N axis remained significantly lower than in the +N axis. The concentration of reduced nitrogen, as well as in vitro NO3- reductase activity, was greater in apical than in more basal regions of the +N axis. The enhanced proliferation of lateral branches in the +N axis was accompanied by an increase in total respiration rate of the axis. Part of the increased respiration was attributable to increased mass of roots. The specific respiration rate (micromoles CO2 evolved per hour per gram root dry weight) was also greater for the +N than for the -N axis. If respiration rate is taken as representative of sink demand, stimulation of initiation and growth of laterals by in situ utilization of a localized exogenous supply of NO3- establishes an increased sink demand through enhanced metabolic activity and the increased partitioning of assimilates to the +N axis responds to the difference in sink demand between +N and -N axes.