Transformation and release of micronized Cu used as a wood preservative in treated wood in wetland soil.

Micronized Cu (µ-Cu) is used as a wood preservative, replacing toxic chromated copper arsenate (CCA). Micronized Cu is malachite [Cu2CO3(OH)2] that has been milled to micron/submicron particles, with many particle diameters less than 100 nm, mixed with biocides and then used to treat wood. In addition to concerns about the fate of the Cu from µ-Cu, there is interest in the fate of the nano-Cu (n-Cu) constituents. We examined movement of Cu from µ-Cu-treated wood after placing treated-wood stakes into model wetland ecosystems. Release of Cu into surface and subsurface water was monitored. Surface water Cu reached maximum levels 3 days after stake installation and remained elevated if the systems remained inundated. Subsurface water Cu levels were 10% of surface water levels at day 3 and increased gradually thereafter. Sequential filtering indicated that a large portion of the Cu in solution was associating with soluble organics, but there was no evidence for n-Cu in solution. After 4 months, Cu in thin-sections of treated wood and adjacent soil were characterized with micro X-ray absorption fine structure spectroscopy (µ-XAFS). Localization and speciation of Cu in the wood and adjacent soil using µ-XAFS clearly indicated that Cu concentrations decreased over time in the treated wood and increased in the adjacent soil. However, n-Cu from the treated wood was not found in the adjacent soil or plant roots. The results of this study indicate that Cu in the µ-Cu-treated wood dissolves and migrates into adjacent soil and waters primarily in ionic form (i.e., Cu2+) and not as nano-sized Cu particles. A reduced form of Cu (Cu2S) was identified in deep soil proximal to the treated wood, indicating strong reducing conditions. The formation of the insoluble Cu2S effectively removes some portion of dissolved Cu from solution, reducing movement of Cu2+ to the water column and diminishing exposure.

Modeling Anthropogenic and Environmental Influences on Freshwater Harmful Algal Bloom Development Detected by MERIS Over the Central United States.

Human and ecological health have been threatened by the increase of cyanobacteria harmful algal blooms (cyanoHABs) in freshwater systems. Successful mitigation of this risk requires understanding the factors driving cyanoHABs at a broad scale. To inform management priorities and decisions, we employed random forest modeling to identify major cyanoHAB drivers in 369 freshwater lakes distributed across 15 upper Midwest states during the 2011 bloom season (July-October). We used Cyanobacteria Index (CI_cyano)-A remotely sensed product derived from the MEdium Resolution Imaging Spectrometer (MERIS) aboard the European Space Agency's Envisat satellite-as the response variable to obtain variable importance metrics for 75 landscape and lake physiographic predictor variables. Lakes were stratified into high and low elevation categories to further focus CI_cyano variable importance identification by anthropogenic and natural influences. "High elevation" watershed land cover (LC) was primarily forest or natural vegetation, compared with "low elevation" watersheds LC dominated by anthropogenic landscapes (e.g., agriculture and municipalities). We used the top ranked 25 Random Forest variables to create a classification and regression tree (CART) for both low and high elevation lake designations to identify variable thresholds for possible management mitigation. Mean CI_cyano was 3 times larger for "low elevation" lakes than for "high elevation" lakes, with both mean values exceeding the "High" World Health Organization recreational guidance/action level threshold for cyanobacteria (100,000 cells/mL). Agrarian-related variables were prominent across all 369 lakes and low elevation lakes. High elevation lakes showed more influence of lakeside LC than for the low elevation lakes.

The role of fetal inflammatory response syndrome and fetal anemia in nonpreventable term neonatal encephalopathy.

OBJECTIVE: To evaluate asphyxial patterns in term encephalopathic newborns caused by chorioamnionitis or intrapartum blood loss that resulted in cerebral palsy and allegations of obstetrical professional liability. STUDY DESIGN: As an expert witness, JKM identified term newborns with profound neurologic impairment: 18 born in the presence of chorioamnionitis and 14 with significant anemia. RESULT: In both study groups, profound depression with low 10-min Apgars was associated with early-onset seizures (88%), multiorgan failure (94%) and a partial prolonged injury to the cortex and subcortical white matter (94%). A cord arterial pH>7.00 was noted in 68% and deep gray matter injury involving the basal ganglia and thalamus occurred in only 19% of the newborns studied. CONCLUSION: The cord arterial pH and pCO2 values, early-onset seizures and paucity of isolated deep gray matter injury support that significant injury occurred postnatally despite appropriate resuscitation. This unique pattern may refute allegations of obstetrical mismanagement in the intrapartum period.

Effects of circuit resistance training and timely protein supplementation on exercise-induced fat oxidation in tetraplegic adults.

BACKGROUND: Substrate utilization during exercise in persons with spinal cord injury (SCI) remains poorly defined. PURPOSE: To investigate effects of circuit resistance training (CRT) and timing of protein supplementation (PS) on fuel utilization in persons with tetraplegia. METHODS: Eleven individuals with chronic tetraplegia underwent 6 months of CRT 3 times weekly. Five randomly assigned participants received immediate PS (iPS) administered in split doses prior to and following all exercise sessions. Other participants consumed a matched dose of PS that was delayed until 24 hours post-exercise (dPS). Participants underwent a maximal graded exercise test (GXT) to volitional exhaustion at 4 conditioning time points: 3 months before (-3mo), at the beginning of (0mo), 3 months into (3mo), and 6 months following (6mo) the CRT conditioning program. Respiratory measures were continuously obtained throughout the GXT via open-circuit spirometry. Fuel utilization and energy expenditure were computed from the respiratory data. RESULTS: The differences in changes in substrate utilization between the PS groups were not significant as determined by the interaction of PS group and conditioning time point, F (3, 27) = 2.32, P = .098, η(2) P = .205. Maximal absolute fat oxidation did not change significantly from 0 to 6mo (mean difference, 0.014 ± 0.031 g/min; P = .170), and fat oxidation remained low never exceeding an average of 0.10 ± 0.09 g/min for any given exercise intensity. CONCLUSION: Maximum fat utilization during exercise and fat utilization at matched exercise intensities were not increased in persons with tetraplegia, independent of PS, and levels of fat oxidation remained low after training.

Exercise participation barrier prevalence and association with exercise participation status in individuals with spinal cord injury.

STUDY DESIGN: Pass-code protected web survey. OBJECTIVES: Defining exercise participation barrier prevalence and association with exercise participation status in adults with spinal cord injury (SCI). SETTING: World-wide web. METHODS: Individuals ≥18 years with ShCI in the United States completed a pass-code protected website survey (N=180). Odds ratios (OR) and OR 95% confidence interval (95% CI) assessed association between barrier presence and exercise participation. RESULTS: No differences existed between exercisers and non-exercisers with respect to age, gender, injury level, injury duration, education level, or employment status. A larger percentage of non-exercisers reported household annual incomes <$7,500. The five most prevalent barriers were not associated with participation status (all OR 95% CI included 1). Low prevalence (≤13%) characterized four of the five barriers most strongly related to being a non-exerciser. Identifying too lazy, too difficult, or no interest as a barrier decreased odds of being an exerciser by 86%, 83%, and 71%, respectively. Not liking exercise decreased the odds of being an exerciser by 90%. CONCLUSION: Highly prevalent barriers were not associated with exercise participation status, whereas low prevalence barriers were strongly related to being a non-exerciser. Internal barriers had the strongest association with exercise participation status. The possible association between socioeconomic factors and exercise participation may be underappreciated. The most effective interventions to increase exercise participation may be multifocal approaches to enhance internal perceptions about and motivation to exercise, increase knowledge of how and where to exercise, while also reducing program and transportation financial costs.

Linking land cover and water quality in New York City's water supply watersheds.

The Catskill/Delaware reservoirs supply 90% of New York City's drinking water. The City has implemented a series of watershed protection measures, including land acquisition, aimed at preserving water quality in the Catskill/Delaware watersheds. The objective of this study was to examine how relationships between landscape and surface water measurements change between years. Thirty-two drainage areas delineated from surface water sample points (total nitrogen, total phosphorus, and fecal coliform bacteria concentrations) were used in step-wise regression analyses to test landscape and surface-water quality relationships. Two measurements of land use, percent agriculture and percent urban development, were positively related to water quality and consistently present in all regression models. Together these two land uses explained 25 to 75% of the regression model variation. However, the contribution of agriculture to water quality condition showed a decreasing trend with time as overall agricultural land cover decreased. Results from this study demonstrate that relationships between land cover and surface water concentrations of total nitrogen, total phosphorus, and fecal coliform bacteria counts over a large area can be evaluated using a relatively simple geographic information system method. Land managers may find this method useful for targeting resources in relation to a particular water quality concern, focusing best management efforts, and maximizing benefits to water quality with minimal costs.

Modes, benefits, and risks of voluntary an delectrically induced exercise in persons with spinal cord injury.

BACKGROUND: Sedentary lifestyles and physical deconditioning are commonly reported among persons with spinal cord injury (SCI), although many forms of exercise have been shown to be beneficial. For individuals unable to perform voluntary exercise, involuntary exercise by electrically stimulated contractions has been used to train individual body segments, invoke cycling movements with or without arm propulsion, and stimulate ambulation. OBJECTIVE: To evaluate the benefits and risks associated with various modes of exercise in persons with SCI. METHODS: Literature review. FINDINGS: Electrical stimulation of local muscle sites increases muscle mass and circulation and favorably alters muscle fiber composition. Electrically stimulated cycling has been observed to improve fitness, lower-extremity circulation, and circulatory response to ischemia and to reverse cardiac muscle atrophy in persons with tetraplegia. Electrically stimulated ambulation improves upper-extremity endurance, lower-extremity circulation, and perception of body image. Studies of arm and wheelchair ergometry show increased arm endurance and decreased cardiovascular risks associated with hyperlipidemia, while resistance training of the upper extremities improves strength and endurance. Because autonomic hyperreflexia, orthostatic intolerance, thermal dysregulation, and fracture are associated with exercise in SCI, risk reduction strategies and prompt intervention are required. CONCLUSIONS: Well-designed programs of exercise are beneficial for persons with tetraplegia and paraplegia. Risks and benefits vary with level of injury. Programs need to address prevention of and intervention for potential adverse effects associated with exercise in individuals with spinal cord dysfunction.

Circuit resistance training improves the atherogenic lipid profiles of persons with chronic paraplegia.

BACKGROUND: People with chronic paraplegia frequently experience dyslipidemias characterized by depressed levels of high-density lipoprotein cholesterol (HDL-C) and elevated levels of low-density lipoprotein cholesterol (LDL-C). These abnormal lipid profiles and poor fitness levels increase their risk for cardiovascular disease. METHODS: To test the hypothesis that circuit resistance exercise training improves both upper-extremity fitness and the atherogenic lipid profile in persons with chronic paraplegia, a homogeneous cohort of 5 men with neurologically complete spinal cord injuries at T6 to L1 underwent 3 months of exercise training using uninterrupted resistance and endurance exercises of the upper extremities. Training was performed 3 times a week on alternating days. RESULTS: Results of graded arm exercise testing showed a 30.3% improvement in peak oxygen consumption (P < .01), a 33.5% increase in time to fatigue (P < .01) and a 30.4% increase in peak power output (P < .05). Pretraining total cholesterol levels (TC) were in the low-risk category and were nonsignificantly lowered following training. Similar nonsignificant reductions of plasma triglycerides averaging 12 mg/dL were attained. Conversely, a 25.9% lowering of LDL-C (P < .05) and 9.8% elevation of HDL-C (P < .05) were observed after training. These changes reduced the average LDL-C-to-HDL-C ratio by 1 unit (P < .05) and the TC-to-HDL-C ratio from 5.0 +/- 1.1 (mean +/- SD) to 3.9 +/- 0.7 (P < .05). CONCLUSIONS: This change reflects a cardiovascular risk reduction of almost 25%; the TC/HDL-C declined from the high-risk score of 5.0 to near the desired score of 3.5. These findings support the beneficial effects of circuit exercise resistance training on fitness and atherogenic lipid profiles in persons with chronic paraplegia.

Enhanced inducible mGlu1alpha receptor expression in Chinese hamster ovary cells.

Inducible expression of the group-I metabotropic glutamate receptor (mGlu1alpha) in Chinese hamster ovary cells allows for the study of receptor density dependent effects. However, expression levels attainable with this system are lower than those reported for various brain regions and achieved by conventional (constitutive) transfection. Thus, direct comparison of mGlu1alpha receptor-mediated responses in this inducible expression system with those for receptors expressed heterologously or in vivo is compounded. We show here that inducible expression can be selectively augmented by butyrate pretreatment to levels approaching those reported for cerebral tissue. Enhanced mGlu1alpha receptor protein levels, agonist-induced inositol phosphate accumulation, as well as single-cell inositol 1,4,5-trisphosphate production and intracellular Ca(2+) mobilization occurred following co-induction with butyrate. In contrast, endogenous purinoceptor function was unaffected. Importantly, the ability to titrate receptor expression by varying isopropyl beta-thiogalactoside concentration was retained. Sodium butyrate thus offers a simple and convenient method to enhance inducible gene expression to levels found in vivo.

Single-cell imaging of graded Ins(1,4,5)P3 production following G-protein-coupled-receptor activation.

The pleckstrin homology domain of phospholipase Cdelta1 (PH(PLCdelta)) binds Ins(1,4,5)P(3) and PtdIns(4,5)P(2) specifically, and can be used to detect changes in Ins(1,4,5)P(3) in single cells. A fusion construct of PH(PLCdelta) and enhanced green fluorescent protein (EGFP-PH(PLCdelta)) associates with the plasma membrane due to its association with PtdIns(4,5)P(2). However, PH(PLCdelta) has greater affinity for Ins(1,4,5)P(3) than PtdIns(4,5)P(2), and translocates to the cytosol as Ins(1,4,5)P(3) levels rise. Prolonged activation of group I metabotropic glutamate receptor 1alpha expressed in Chinese-hamster ovary cells or endogenous M(3) muscarinic receptors in SH-SY5Y neuroblastoma cells gave an initial transient peak in translocation, followed by a sustained plateau phase. This closely followed changes in cell population Ins(1,4,5)P(3) mass, but not PtdIns(4,5)P(2) levels, which decreased monophasically, as determined by radioreceptor assay. Translocation thus provides a real-time method to follow increases in Ins(1,4,5)P(3). Graded changes in Ins(1,4,5)P(3) in Chinese-hamster ovary-lac-mGlu1alpha cells could be detected with increasing glutamate concentrations, and dual loading with fura 2 and EGFP-PH(PLCdelta) showed that changes in intracellular Ca(2+) concentration closely paralleled Ins(1,4,5)P(3) production. Moreover, Ins(1,4,5)P(3) accumulation and intracellular Ca(2+) mobilization within single cells is graded in nature and dependent on both agonist concentration and receptor density.

Circuit training provides cardiorespiratory and strength benefits in persons with paraplegia.

PURPOSE: This study tested the safety and the effects of circuit resistance training (CRT) on peak upper extremity cardiorespiratory endurance and muscle strength in chronic survivors of paraplegia due to spinal cord injury. METHODS: Ten men with chronic neurologically complete paraplegia at the T5-L1 levels participated in the study. Subjects completed 12 wk of CRT, using a series of alternating isoinertial resistance exercises on a multi-station gym and high-speed, low-resistance arm ergometry. Peak arm ergometry tests, upper extremity isoinertial strength testing, and testing of upper extremity isokinetic strength were all performed before and after training. RESULTS: None of the subjects suffered injury from exercise training. Significant increases were observed in peak oxygen consumption (29.7%, P < 0.01), time to fatigue (P < 0.01), and peak power output during arm testing (P < 0.05). Significant increases in isoinertial strength for the training maneuvers ranged from 11.9% to 30% (Ps < 0.01). Significant increases in isokinetic strength were experienced for shoulder joint internal rotation, extension, abduction, adduction, and horizontal adduction (Ps < 0.05). CONCLUSION: Chronic survivors of paraplegia safely improve their upper extremity cardiorespiratory endurance and muscle strength when undergoing a short-term circuit resistance training program. Gains in fitness and strength exceeded those usually reported after either arm endurance exercise conditioning or strength training in this subject population.

Reassessment of the Ca2+ sensing property of a type I metabotropic glutamate receptor by simultaneous measurement of inositol 1,4,5-trisphosphate and Ca2+ in single cells.

Transient transfection of Chinese hamster ovary or baby hamster kidney cells expressing the Group I metabotropic glutamate receptor mGlu1alpha with green fluorescent protein-tagged pleckstrin homology domain of phospholipase Cdelta1 allows real-time detection of inositol 1,4,5-trisphosphate. Loading with Fura-2 enables simultaneous measurement of intracellular Ca(2+) within the same cell. Using this technique we have studied the extracellular calcium sensing property of the mGlu1alpha receptor. Quisqualate, in extracellular medium containing 1.3 mm Ca(2+), increased inositol 1,4,5-trisphosphate in all cells. This followed a typical peak and plateau pattern and was paralleled by concurrent increases in intracellular Ca(2+) concentration. Under nominally Ca(2+)-free conditions similar initial peaks in inositol 1,4,5-trisphosphate and Ca(2+) concentration occurred with little change in either agonist potency or efficacy. However, sustained inositol 1,4,5-trisphosphate production was substantially reduced and the plateau in Ca(2+) concentration absent. Depletion of intracellular Ca(2+) stores using thapsigargin abolished quisqualate-induced increases in intracellular Ca(2+) and markedly reduced inositol 1,4,5-trisphosphate production. These data suggest that the mGlu1alpha receptor is not a calcium-sensing receptor because the initial response to agonist is not sensitive to extracellular Ca(2+) concentration. However, prolonged activation of phospholipase C requires extracellular Ca(2+), while the initial burst of activity is highly dependent on Ca(2+) mobilization from intracellular stores.

5-Hydroxytryptamine1A agonists: potential use in glaucoma. Evidence from animal studies.

Various classes of compounds exist to lower intraocular pressure (IOP) in the treatment of glaucoma. None of them is ideal since some patients respond better than others and the side effects vary between individuals. New classes of compounds need to be introduced to allow the clinician greater scope for effective treatment of all patients. It is now generally agreed that the cause of ganglion cell dysfunction in glaucoma is likely to be multifactorial and that concentrating solely on reducing IOP is inadequate. Irrespective of the reason for the dysfunction, the future goal must be to attenuate cell death. This may be achieved with drugs that interact with components of the retina, and is termed 'neuroprotection'. Thus, drugs that can both reduce IOP and act as neuroprotectants would be ideal for the treatment of glaucoma. In this article we summarise studies on animals which show serotonergic 5-HT1A agonists to both reduce IOP when topically applied to the rabbit eye and blunt the damaging effect to the rat retina and ganglion cells induced by glutamate toxicity or ischaemia. Reduction of IOP occurs via stimulation of 5-HT1A receptors associated with the ciliary processes. Neuroprotection of retinal neurones appears to involve the interaction of 5-HT1A agonists with membrane sodium channels and/or 5-HT1A or even possibly 5-HT7 receptors. Various 5-HT1A agonists are used in patients to treat depression, so classes of these drugs have a proven safety profile for use in patients. The animal studies summarised in this article suggest that 5-HT1A agonists need to be considered as a new class of drugs for the treatment of glaucoma.

Known and plausible modulators of depressed immune functions following spinal cord injuries.

Recent evidence suggests that depression of immune function occurs early after spinal cord injury (SCI) and is maintained thereafter. Deviations from immune function observed in healthy persons with intact neuraxes include natural killer cell number and cytotoxicity, T cell function and activation, macrophage phagocytosis, levels of interleukins (IL)-2 and -6, the soluble IL-2R receptor, and intracellular adhesion molecules. While a single etiology explaining these abnormalities has not been identified, decentralization of the autonomic nervous system is the most likely cause. Otherwise, many persons with SCI, who sustain episodic autonomic overstimulation, are among the most physically deconditioned of all humans, and often select a diet rich in fat and low in protein. All of these are associated with suppressed immune function in persons without SCI. Those with SCI may also be (over)exposed to drugs and medications that suppress immune function, including methylprednisolone administered immediately after traumatic injury. No evidence suggests that the immune profiles of persons with SCI favor disease and illness resistance. As opportunistic infections of the urinary tract, lungs, and skin represent major causes of morbidity for those aging with SCI, attention to, or intervention on, immune suppressive states, traits, behaviors, diets, and medications may represent a means through which host defenses of persons with SCI can be fortified and their illness proclivities reduced.

Immune dysfunction and illness susceptibility after spinal cord injury: an overview of probable causes, likely consequences, and potential treatments.

Information contained in the following monographs was presented as a symposium at the Annual Conference of the American Paraplegia Society in September 1999.

Flupirtine ameliorates ischaemic-like death of rat retinal ganglion cells by preventing calcium influx.

The effect of flupirtine on the loss of retinal ganglion cells following transient elevation of intraocular pressure (experimental ischaemia) or NMDA-induced excitotoxicity was studied. Ischaemia (60 min) or intravitreal injection of NMDA (20 nmol) caused a decrease in Thy-1 mRNA and Thy-1 immunoreactivity which are associated with ganglion cells. Administration of flupirtine counteracted these changes. Moreover, flupirtine dose-dependently inhibited NMDA-induced 45Ca(2+) influx into cultured cortical neurones and retinal pieces in vitro with maximal inhibition being observed at 200 microM. A similar concentration of flupirtine failed to inhibit kainate-stimulated calcium influx into cultured cortical neurones. In addition, flupirtine had no significant effect on [3H]nitrendipine or [3H]diltiazem binding to cortical membranes. The present studies are consistent with previous findings which suggested flupirtine to act as a NMDA antagonist by a mechanism that still remains to be clarified.

A randomized blinded comparison of two methods used for venous antistasis in tetraplegia.

OBJECTIVE: The hemodynamic effects of slow sequential compression (SCD) were compared with rapid intermittent pulsatile compression (IPC) in subjects with complete tetraplegia. METHODS: Twenty subjects underwent Doppler examination of the bilateral popliteal and femoral veins. Resting volume flow per minute (VFM), average venous velocity (AVV), and maximal venous velocity (MVV) were measured in both veins. SCD and IPC were then randomly applied to one limb each, followed by repeat Doppler measurements under compression conditions. Doppler spectral recordings were stored for future analysis, and then measured by an investigator blinded to testing conditions (rest versus compression) and device (SCD versus IPC). RESULTS: Sequential compression and IPC compression both increased popliteal and femoral vein VFM, AVV, and MVV above resting levels (all p's < 0.001). In the femoral vein VFM (p < 0.05) and MVV (p < 0.05) were augmented during IPC compared to SCD compression. CONCLUSION: As MVV best reflects performance effectiveness of compression devices, these data find IPC more effective than SCD for stimulating venous blood flow in subjects with tetraplegia.