Impacts of Desalination Brine Discharge on Benthic Ecosystems

Seawater reverse osmosis (SWRO) desalination facilities produce freshwater and, at the same time, discharge hypersaline brine that often includes various chemical additives such as antiscalants and coagulants. This dense brine can sink to the sea bottom and creep over the seabed, reaching up to 5 km from the discharge point. Previous reviews have discussed the effects of SWRO desalination brine on various marine ecosystems, yet little attention has been paid to the impacts on benthic habitats. This review comprehensibly discusses the effects of SWRO brine discharge on marine benthic fauna and flora. We review previous studies that indicated a suite of impacts by SWRO brine on benthic organisms, including bacteria, seagrasses, polychaetes, and corals. The effects within the discharge mixing zones range from impaired activities and morphological deformations to changes in the community composition. Recent modeling work demonstrated that brine could spread over the seabed, beyond the mixing zone, for up to several tens of kilometers and impair nutrient fluxes from the sediment to the water column. We also provide a possible perspective on brine's impact on the biogeochemical process within the mixing zone subsurface. Desalination brine can infiltrate into the sandy bottom around the discharge area due to gravity currents. Accumulation of brine and associated chemical additives, such as polyphosphonate-based antiscalants and ferric-based coagulants in the porewater, may change the redox zones and, hence, impact biogeochemical processes in sediments. With the demand for drinking water escalating worldwide, the volumes of brine discharge are predicted to triple during the current century. Future efforts should focus on the development and operation of viable technologies to minimize the volumes of brine discharged into marine environments, along with a change to environmentally friendly additives. However, the application of these technologies should be partly subsidized by governmental stakeholders to safeguard coastal ecosystems around desalination facilities.

Tar pollution event (2021) at the Southeastern Levantine oligotrophic basin, short-term impacts and operational oceanography perspectives

The Levantine basin (LB) in the Southeastern Mediterranean Sea is a high-risk oil pollution hot spot owing to its dense maritime traffic and intense oil and gas exploration and exploitation activities. In February 2021 the Israeli LB shorelines were impacted by an exceptional tar pollution event (~550 tons; average distribution: ~3 kg tar m-1 front beach) of an unknown oil spill source. Here we report on the immediate numerical modelling assessment of the oil spill propagation and tar distribution; operational use of underwater gliders for tracking water column anomalies of dissolved polycyclic aromatic hydrocarbons (PAHs) and turbidity signals; the beached tar composition and amounts and the short-term response of the microbial population along the ~180 km shoreline. This pollution event emphasizes the need for improving the early warning systems for oil spills and implementing continuous operational monitoring at high-risk, ecologically sensitive and valuable resource areas like the Israeli LB waters.

A220 AN UNEXPECTED CAUSE OF ACUTE JAUNDICE IN A POST-TRANSPLANT PATIENT

Background

Complications post liver transplantation are common. These may include thromboses, primary graft nonfunction, biliary complications, chylothorax, infection, and rejection. Hepaticojejunostomy with Roux-en-Y limb is a common technique for pediatric liver transplantation. Complications of hepaticojejunostomy include small bowel obstruction due to incarceration of the Roux-en-Y limb within an internal hernia. Acquired diaphragmatic hernia has previously been reported in liver transplant patients. Here we present a unique case of acute biliary obstruction secondary to incarceration of a Roux limb within an acquired diaphragmatic hernia.

Aims

To describe a unique case of incarcerated Roux-en-Y limb in a diaphragmatic hernia leading to acute jaundice in a pediatric liver transplant patient.

Methods

Retrospective chart review and case review with the surgical and medical teams.

Results

A 14 month old girl with unresectable hepatoblastoma received a living donor, left lateral segment liver transplant using standard venous reconstruction, microvascular plastics arterial reconstruction, and the recipient common hepatic duct was anastomosed to the donor left hepatic duct. Serial ultrasounds showed persistent intrahepatic duct dilatation with cholestasis. Given the concern of biliary obstruction, 10 days post-transplant, she underwent repeat laparotomy and was found to have a dilated common bile duct with a proximal obstruction. A Roux-en-Y hepaticojejunostomy was performed to establish adequate biliary drainage.

Three months post-transplant she developed lung metastases that required wedge resection and chemotherapy. 7 months post-transplant, while admitted for routine chemotherapy she acutely developed jaundice, pruritus, and transaminitis. Liver ultrasound showed an apparent fluid collection at the cut surface of the liver and biliary dilatation. Extrinsic compression of the biliary tree was suspected, and so a percutaneous biliary drain was placed to drain the collection and decompress the biliary system.

Despite improvement in the transaminitis and cholestasis, several days later, she developed severe abdominal pain and associated grunting respirations. An MRI with MRCP to reassess the previous findings and rule out a new intraabdominal cause for her symptoms was completed and unexpectedly showed herniation of her Roux-en-Y limb into a diaphragmatic hernia. She had urgent diaphragmatic hernia repair with reduction of the incarcerated bowel loop, with resolution of her pain and jaundice.

Conclusions

Post liver transplant Roux-en-Y herniation is uncommon, but can occur with internal hernias and in diaphragmatic hernias. This uncommon complication should be considered for the post liver transplant patient with hepaticojejunostomy in the setting of acute jaundice, particularly if accompanied by acute onset abdominal pain and/or increased work of breathing.

Funding Agencies

None

Legacy groundwater pollution as a source of mercury enrichment in marine food web, Haifa Bay, Israel

Haifa Bay (HB), located along the northern Mediterranean shore of Israel was polluted with Hg from a chlor-alkali plant (ECI) and from the Qishon River industries, for decades. From the mid-1980s industrial Hg loads into HB decreased dramatically until their complete cessation in 2000. Consequently, concentrations in marine biota and sediments decreased almost to reference levels. However, during 2006-2014, an unexpected increase of total Hg (THg) concentrations was observed in three commercial fish species collected at northern HB (N.HB). To determine the cause of this increase, THg and methyl Hg (MeHg) were measured in seawater, coastal groundwater, suspended particulate matter, plankton, macroalgae, benthic fauna, and in marine and beach sediments. THg in groundwater and sediments from the vicinity of ECI were extremely high (up to 251 μg L^-1 and 2200 ng g^-1, respectively). MeHg concentrations in groundwater were low and constituted <0.1% of THg, except in the surf zone opposite the ECI, where MeHg constituted 0.2% of the THg. THg and MeHg concentrations were consistently higher in benthic biota and plankton from N.HB and northwards, compared to corresponding samples from southern HB (S.HB) and the reference site (RS). MeHg in bivalves and sponges from N.HB and SZ was higher than from S.HB and RS, despite having similar THg concentrations, which suggests a stronger source of MeHg in N.HB. Our findings suggest that the discharge into N.HB of Hg polluted groundwater under the ECI increased during the period 2006-2014. The Hg was assimilated by plankton or adsorbed onto inorganic particles, which were further ingested by benthic and pelagic consumers, as well as transported northward with the alongshore current. These findings demonstrate for the first time the potential of relic pollution in groundwater to increase heavy metal burdens in local marine food webs.

A134 RATES OF PARENTERAL NUTRITION-ASSOCIATED CHOLESTASIS/LIVER DISEASE AND GROWTH PRE- AND POST-SMOFLIPID INTRODUCTION IN NEONATES AND INFANTS WITH INTESTINAL FAILURE

Background

Parenteral nutrition (PN) is essential for survival in infants with intestinal failure (IF). PN-associated cholestasis (PNAC) and liver disease (PNALD) are life-threatening complications of long-term PN use. SMOFlipid (soybean oil, medium-chain triglycerides, olive oil, and fish oil) has recently been approved as an off-label alternative to the conventional soy-based lipid emulsion (Intralipid). It is thought to have anti-cholestatic properties due to its more diverse lipid composition. Due to its’ recent approval in Canada (2013) and the USA (2016), data remains sparse.

Aims

We aim to determine if infants with IF receiving SMOFlipid had significantly lower rates of PNAC and improved growth compared to those receiving Intralipid.

Methods

All patients (≤1 year old at start of PN therapy) who received PN of any duration at two tertiary pediatric hospitals in Edmonton (2010–2018) were identified from the shared pharmacy database. Those with IF who received one type of PN continuously for ≥6 weeks total were included. Individuals with an initial serum conjugated bilirubin &gt;50 µmol/L and/or who had PN interruptions &gt;5 days were excluded. Data on liver parameters, growth, and complications were collected. Non-parametric tests (Mann-Whitney U test for continuous variables and χ2 test for categorical variables) were used to compare PNAC/PNALD (serum conjugated bilirubin &gt;34umol/L during PN) and growth (weight/length/head circumference z-scores) between SMOFlipid and Intralipid.

Results

1777 patients were reviewed; 40 infants (55% male), median age 4 weeks (range 0–48 weeks) at the time of PN initiation, met the inclusion criteria. Reasons for exclusion (n=1737) were receiving PN &lt;6 weeks total (n=1485), duplicate patients (n=154), receiving multiple types of PN with each less than 6 weeks total (n=62), an initial serum conjugated bilirubin &gt;50umol/L (n=21), more than 5 consecutive days off of PN (n=12), and older than 1 year old at time of PN initiation (n=3). Twenty-one patients (53%) received SMOFlipid, 15 (38%) Intralipid, and 4 (10%) Omegaven for ≥6 weeks. The majority (92%) were in an intensive care unit (neonatal or pediatric). No patients were septic when starting PN. Individuals received PN over a median of 7.9 weeks (range 6–27 weeks).

Conclusions

As expected, neonatal onset intestinal failure is rare in Edmonton. In our tertiary pediatric institutions, 2010–2018, SMOFLipid was the predominant lipid choice for infants with intestinal failure, followed by Intralipid. Omegaven was used rarely. This dataset will now allow us to compare the rates of PNAC at six weeks post-PN initiation and differences in growth between infants with IF receiving SMOFlipid versus the traditional Intralipid in our Canadian setting. Analysis is currently underway.

Funding Agencies

Women and Children’s Health Research Institute (WCHRI) at the University of Alberta

Spatial distribution and sources of organic matter and pollutants in the SE Mediterranean (Levantine basin) deep water sediments

A study of deep sea sediment quality was conducted at 52 stations off the Mediterranean coast of Israel (50-1900m depth). Total Organic Carbon (TOC), Polycyclic Aromatic Hydrocarbons (∑PAHs), Poly Chlorinated Biphenyls (∑PCBs) ranged between 0.58 and 1.44%, 12-190 and <0.3-7.7μgkg^-1, respectively. The TOC distribution indicated the Nile delta as an important source of organic matter and the important effect of topography on deposition patterns in this region. PCBs and PAHs quantitative levels were associated with nearby gas well drilling (well below environmental criteria) and dredge-material dumping sites. A significant correlation between these pollutants and TOC was found in the southernmost stations suggesting a common source. PAHs isomer ratios in most of the stations indicated a petrogenic source, while the contribution of pyrogenic sources appears to be very small. These findings form a sound baseline for assessing the potential impact of future deep sea drilling activities that are expected to increase significantly in the Eastern Mediterranean basin.

Seizure-associated central apnea in a rat model: Evidence for resetting the respiratory rhythm and activation of the diving reflex

Respiratory derangements, including irregular, tachypnic breathing and central or obstructive apnea can be consequences of seizure activity in epilepsy patients and animal models. Periods of seizure-associated central apnea, defined as periods >1s with rapid onset and offset of no airflow during plethysmography, suggest that seizures spread to brainstem respiratory regions to disrupt breathing. We sought to characterize seizure-associated central apneic episodes as an indicator of seizure impact on the respiratory rhythm in rats anesthetized with urethane and given parenteral kainic acid to induce recurring seizures. We measured central apneic period onsets and offsets to determine if onset-offset relations were a consequence of 1) a reset of the respiratory rhythm, 2) a transient pausing of the respiratory rhythm, resuming from the pause point at the end of the apneic period, 3) a transient suppression of respiratory behavior with apnea offset predicted by a continuation of the breathing pattern preceding apnea, or 4) a random re-entry into the respiratory cycle. Animals were monitored with continuous ECG, EEG, and plethysmography. One hundred ninety central apnea episodes (1.04 to 36.18s, mean: 3.2±3.7s) were recorded during seizure activity from 7 rats with multiple apneic episodes. The majority of apneic period onsets occurred during expiration (125/161 apneic episodes, 78%). In either expiration or inspiration, apneic onsets tended to occur late in the cycle, i.e. between the time of the peak and end of expiration (82/125, 66%) or inspiration (34/36, 94%). Apneic period offsets were more uniformly distributed between early and late expiration (27%, 34%) and inspiration (16%, 23%). Differences between the respiratory phase at the onset of apnea and the corresponding offset phase varied widely, even within individual animals. Each central apneic episode was associated with a high frequency event in EEG or ECG records at onset. High frequency events that were not associated with flatline plethysmographs revealed a constant plethysmograph pattern within each animal, suggesting a clear reset of the respiratory rhythm. The respiratory rhythm became highly variable after about 1s, however, accounting for the unpredictability of the offset phase. The dissociation of respiratory rhythm reset from the cessation of airflow also suggested that central apneic periods involved activation of brainstem regions serving the diving reflex to eliminate the expression of respiratory movements. This conclusion was supported by the decreased heart rate as a function of apnea duration. We conclude that seizure-associated central apnea episodes are associated with 1) a reset of the respiratory rhythm, and 2) activation of brainstem regions serving the diving reflex to suppress respiratory behavior. The significance of these conclusions is that these details of seizure impact on brainstem circuitry represent metrics for assessing seizure spread and potentially subclassifying seizure patterns.

Laryngospasm, central and obstructive apnea during seizures: Defining pathophysiology for sudden death in a rat model

Seizure spread into the autonomic nervous system can result in life-threatening cardiovascular and respiratory dysfunction. Here we report on a less-studied consequence of such autonomic derangements-the possibility of laryngospasm and upper-airway occlusion. We used parenteral kainic acid to induce recurring seizures in urethane-anesthetized Sprague Dawley rats. EEG recordings and combinations of cardiopulmonary monitoring, including video laryngoscopy, were performed during multi-unit recordings of recurrent laryngeal nerve (RLN) activity or head-out plethysmography with or without endotracheal intubation. Controlled occlusions of a tracheal tube were used to study the kinetics of cardiac and respiratory changes after sudden obstruction. Seizure activity caused significant firing increases in the RLN that were associated with abnormal, high-frequency movements of the vocal folds. Partial airway obstruction from laryngospasm was evident in plethysmograms and was prevented by intubation. Complete glottic closure (confirmed by laryngoscopy) occurred in a subset of non-intubated animals in association with the largest increases in RLN activity, and cessation of airflow was followed in all obstructed animals within tens of seconds by ST-segment elevation, bradycardia, and death. Periods of central apnea occurred in both intubated and non-intubated rats during seizures for periods up to 33s and were associated with modestly increased RLN activity, minimal cardiac derangements, and an open airway on laryngoscopy. In controlled complete airway occlusions, respiratory effort to inspire progressively increased, then ceased, usually in less than 1min. Respiratory arrest was associated with left ventricular dilatation and eventual asystole, an elevation of systemic blood pressure, and complete glottic closure. Severe laryngospasm contributed to the seizure- and hypoxemia-induced conditions that resulted in sudden death in our rat model, and we suggest that this mechanism could contribute to sudden death in epilepsy.

A methanotroph-based biorefinery: Potential scenarios for generating multiple products from a single fermentation

Methane, a carbon source for methanotrophic bacteria, is the principal component of natural gas and is produced during anaerobic digestion of organic matter (biogas). Methanotrophs are a viable source of single cell protein (feed supplement) and can produce various products, since they accumulate osmolytes (e.g. ectoine, sucrose), phospholipids (potential biofuels) and biopolymers (polyhydroxybutyrate, glycogen), among others. Other cell components, such as surface layers, metal chelating proteins (methanobactin), enzymes (methane monooxygenase) or heterologous proteins hold promise as future products. Here, scenarios are presented where ectoine, polyhydroxybutyrate or protein G are synthesised as the primary product, in conjunction with a variety of ancillary products that could enhance process viability. Single or dual-stage processes and volumetric requirements for bioreactors are discussed, in terms of an annual biomass output of 1000 tonnesyear(-1). Product yields are discussed in relation to methane and oxygen consumption and organic waste generation.

MP11: COMORBID DEPRESSION OR ANXIETY IS ASSOCIATED WITH AORTIC VASCULAR INFLAMMATION AND CORONARY HEART DISEASE BEYOND TRADITIONAL CARDIOVASCULAR RISK FACTORS IN PSORIASIS

Purpose of Study

Psoriasis is a chronic inflammatory disorder associated with vascular inflammation (VI), measured by 18-fluorodeoxyglucose positron emission tomography/computed tomography (18-FDG PET/CT), and increased risk of MI. Patients with psoriasis are more likely to have comorbid depression and anxiety. Whether these comorbidities accelerate the development of CVD in psoriasis is unclear. We hypothesized that aortic VI and coronary plaque burden would be increased in patients with psoriasis who have depression and/or anxiety compared to those with psoriasis who do not.

Methods Used

Patients were prospectively enrolled. Those who reported a history of depression and/or anxiety (n=40) on survey and age- and gender-matched patients who reported no history of psychiatric illness (n=40) were selected. Target-to-Background ratio from 18FDG PET/CT was used to assess aortic VI, and coronary CT angiography scans were analyzed for coronary plaque composition.

Summary of Results

Both aortic VI and coronary plaque burden were higher in psoriasis patients with comorbid depression or anxiety compared to those without (table 1). After adjustment for Framingham Risk Score, body mass index, and statin use; VI (β=0.24, p=0.02), total plaque burden (β=0.13, p=0.04), and non-calcified burden (β=0.13, p=0.04) were associated with comorbid depression and/or anxiety.

Conclusions

Patients with psoriasis who have comorbid depression or anxiety have increased aortic VI and coronary plaque burden, suggesting that identification of psychiatric diagnoses in psoriasis may be warranted for future CV risk reduction in this high risk population.

Abstract MP11 Figure 1

21: DETERMINANTS OF VASCULAR INFLAMMATION BY 18-FLUORODEOXYGLUCOSE PET/MRI: FINDINGS FROM THE PSORIASIS, ATHEROSCLEROSIS AND CARDIOMETABOLIC DISEASE INITIATIVE

Purpose of Study

Psoriasis (PSO), a chronic inflammatory disease associated with increased CV risk, provides a clinical human model to study inflammatory atherogenesis. We aimed to assess the major determinants of vascular inflammation (VI) measured by 18FDG PET-MRI in a well-phenotyped PSO cohort.

Methods Used

124 consecutive patients with PSO underwent 18FDG PET-MRI scans. We used target-to-background ratio to quantify VI 120 minutes post FDG injection. Homeostatic model assessment of insulin resistance (HOMA-IR) was measured, along with cholesterol efflux capacity (CEC) and HDL particle concentration by NMR (Liposcience) fasting.

Summary of Results

Our cohort was middle aged (mean 49±13.3 years) with mild to moderate PSO, and low CV risk (median Framingham Risk Score (FRS) 2, IQR 2–6). PSO was associated with increased VI (β=0.27, p<0.005), compared to healthy controls. VI was associated with HOMA-IR (β=0.26, p<0.001), CEC (β=−0.12, p=0.04) and HDL particle concentration (β=−0.19, p=0.003) beyond traditional CV risk factors (age, gender, FRS and BMI). Among these, HOMA-IR provided maximum incremental value in predicting VI beyond traditional risk factors (χ2=39.36, p<0.001).

Conclusions

VI by FDG PET MRI is associated with traditional CV risk factors and cardiometabolic parameters. Insulin resistance and CEC were most strongly associated with VI by 18FDG PET-MRI beyond traditional CV risk factors and BMI in PSO suggesting that cardiometabolic disease increases CV risk in PSO.

Abstract 21 Figure 1

23: VASCULAR INFLAMMATION AND AORTIC WALL CHARACTERISTICS MODULATE FOLLOWING LIFESTYLE CHANGES IN PSORIASIS PATIENTS AT 1 YEAR FOLLOW UP

Purpose of Study

Psoriasis (PSO), a chronic inflammatory skin disease, is associated with increased CV risk and vascular inflammation (VI). However, the effect of therapeutic lifestyle changes (TLC) including exercise on VI over time is unknown. We hypothesized that TLC would lead to an improvement in VI at 1 year accompanied by improvements in aortic wall characteristics.

Methods Used

65 PSO patients, recruited consecutively, underwent FDG PET/CT, phase contrast MRI scans and clinical visits for evaluation of VI, wall characteristics and exercise frequency, at baseline and 1 year follow-up. VI was measured as Target-to-background ratio (TBR), and aortic distensibility (AD) and wall thickness were assessed by commercial software on phase contrast MRI scans. Clinical parameters were ascertained by both survey and provider.

Summary of Results

VI decreased at 1 year (6.5% decrease in TBR; p<0.0001), and was inversely associated with exercise frequency beyond adjustment for CV risk factors (β=−0.27; p=0.001). Furthermore, this decrease in VI was associated with improvement in AD (40% increase; p<0.001) and aortic wall thickness (8.5% decrease; p<0.001).

Conclusions

Our findings suggest that VI improves with TLC. This 6.5% decrease in VI could lead to ∼30% reduction in future adverse events, based on a recent large prospective study. This VI reduction is also associated with improved aortic wall characteristics suggesting that targeting VI as a surrogate marker holds promise to understand the effects of TLC on CV disease.

Abstract 23 Figure 1

18: IMPROVEMENT IN PSORIASIS SKIN DISEASE SEVERITY IS ASSOCIATED WITH REDUCTION OF CORONARY PLAQUE BURDEN

Purpose of Study

Psoriasis (PSO), a chronic inflammatory disease associated with increased cardiovascular (CV) risk, provides a clinical human model to study inflammatory atherogenesis. While PSO severity is associated with both in vivo vascular disease and future CV risk, the longitudinal impact of PSO severity on coronary disease progression is unknown. We hypothesized that an improvement in PSO severity may lead to a reduction in coronary plaque burden by coronary CT angiography (CCTA).

Methods Used

Consecutively recruited PSO patients (N=50) underwent CCTA (320 detector row, Toshiba) and cardiometabolic profiling at baseline and 1-year follow-up. Total (TB) and non-calcified (NCB) coronary plaque burden were quantified using QAngio (Medis, Netherlands). PSO severity was measured as the psoriasis area severity index (PASI). The longitudinal change in coronary plaque burden was analyzed with unadjusted and adjusted regression.

Summary of Results

The cohort had a low Framingham Risk Score and mild to moderate PSO. Patients whose PSO severity improved (ΔPASI −27%; p<0.001) (N=33) had significant improvement in TB (β=0.40, p=0.003) and NCB (β=0.49, p<0.001) (table 1), beyond adjustment for traditional CV risk factors, BMI, statin use, & systemic/biologic PSO therapy.

Conclusions

Improvement in PSO severity was associated with improvement in coronary plaque burden by CCTA. Our study suggests that a reduction in skin inflammation may reduce the progression of early, non-calcified coronary plaque. Larger studies are needed to confirm these findings.

Abstract 18 Figure 1

*P-value is calculated by comparing baseline and 1-year follow-up values for variables using paired t-test for continuous variables, and Pearson's chi-squared test for categorical variables. All values are expressed as Mean±SD, unless specified otherwise. PASI: Psoriasis Area Severity Index.

A short-term in situ CO₂ enrichment experiment on Heron Island (GBR)

Ocean acidification poses multiple challenges for coral reefs on molecular to ecological scales, yet previous experimental studies of the impact of projected CO₂ concentrations have mostly been done in aquarium systems with corals removed from their natural ecosystem and placed under artificial light and seawater conditions. The Coral–Proto Free Ocean Carbon Enrichment System (CP-FOCE) uses a network of sensors to monitor conditions within each flume and maintain experimental pH as an offset from environmental pH using feedback control on the injection of low pH seawater. Carbonate chemistry conditions maintained in the −0.06 and −0.22 pH offset treatments were significantly different than environmental conditions. The results from this short-term experiment suggest that the CP-FOCE is an important new experimental system to study in situ impacts of ocean acidification on coral reef ecosystems.

Characterization of Thin PtSI/p-Si Schottky Diodes

A series of PtSi on p-type Si diodes have been characterized in order to establish correlations among processing parameters, metallurgical features and electrical properties. Characterization techniques include analytical (TED, TEM), electrical (current-voltage characteristics), and optical (photoemission and absorption). The fabrication techniques involve e-beam evaporation of platinum layers at UHV levels onto VLSI grade (100) p-type silicon substrates. The silicide layers are formed via sub-eutectic solid state diffusion at 350°C. The main trends with thickness as well as possible interrelationships are described. An unexpected result is the presence of unreacted polycrystalline Pt and Pt2Si at the interface.

Combined effect of hemipteran control and liquid bait on Argentine ant populations

The invasive Argentine ant, Linepithema humile (Mayr), has become a worldwide problem capable of inflicting significant ecological and economic injury on urban, agricultural, and natural environments. The mobility of this pest ant has long been noted, rapidly moving nests to new food resources and then away as resources are depleted. This ant, like many pest ant species, has a special affinity for honeydew excreted by phloem-feeding Hemiptera. We investigated the effect of various hemipteran control strategies on terrapin scale densities and measured their indirect effect on local Argentine ant densities and foraging effort. We then determined whether this indirect treatment strategy improved the performance of an ant bait. We predicted that Argentine ants would move nests away from trees treated for Hemiptera and then move nests back when a liquid bait was offered, followed by a decline in ant numbers due to intake of the toxicant. A horticultural oil spray and soil application of the systemic insecticide, imidacloprid, had no effect on terrapin scale numbers. However, trunk-injected dicrotophos caused a reduction in scale and a decline in local Argentine ant nest density and canopy foraging effort. We also recorded a reduction in local Argentine ant ground foraging when large amounts of liquid bait were applied, and we found no evidence that combining dicrotophos with liquid ant bait performed better than each treatment alone. We suggest that a strategy of combined hemipteran control plus application of liquid ant bait can reduce local Argentine ant densities, when both components of this system are highly efficacious.

Northward expansion of the invasive Linepithema humile (Hymenoptera: Formicidae) in the eastern United States is constrained by winter soil temperatures

The invasive Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae) has been evident in the North Carolina Piedmont, United States for 90 yr but has failed to spread further north. We investigated the mechanisms preventing this expansion. The Argentine ant ceases foraging at temperatures below 5°C and we hypothesized that winter soil temperatures at higher latitudes restricted foraging long enough to cause colony starvation. We tested if the Argentine ant could successfully feed at temperatures below 5°C and found that colonies would starve. We subjected Argentine ant nests to a range of sub- and above-freezing temperatures and measured worker mortality at various time intervals. We found that Argentine ant colonies will collapse after 8.5 d at 5°C. Argentine ants can escape ambient cold temperatures by moving nests into the soil column. We tested how deeply into the soil Argentine ant queens and workers need to move to survive winter in North Carolina. Soil temperatures in the North Carolina Piedmont do not fall below 5°C for longer than nine consecutive days; therefore, Argentine ant colonies need only to retreat a few centimeters into the soil column to escape unsuitable temperatures. Winter soil temperature data from four climate stations situated from latitudes 35°, the current Eastern United States latitudinal limit for Argentine ant population expansion, to 39° were searched for periods where soil temperatures would have led to colony extirpation. North of their current distributions, extended periods of soil temperatures below 5°C regularly occur, preventing Argentine ant colonies from persisting.

Effect of an invasive and native ant on a field population of the black citrus aphid (Hemiptera: Aphididae)

Invasive ants often enter into facultative mutualisms that frequently lead to outbreaks of the hemipteran partner. Native ants may also enter into similar mutualisms but often these do not lead to outbreaks. However, field studies comparing the impact of an invasive and native ant on a honeydew-producing hemipteran are lacking. We monitored numerical changes of the black citrus aphid, Toxoptera aurantii, tended by adjacent colonies of the invasive Argentine ant, Linepithema humile, and the endemic odorous house ant, Tapinoma sessile, during 2005, 2006, and 2007. Ant-tended aphid numbers were higher than those of untended aphids, with L. humile-tended and T. sessile-tended T. aurantii populations being comparable in 2005 and 2007. However, in 2006, a severe storm, with heavy rainfall, reduced T. sessile and aphid populations in areas occupied by T. sessile, whereas L. humile and aphids tended by L. humile were not reduced. This suggested that T. sessile foraging activity and hemipteran-tending was negatively impacted by severe weather. A laboratory experiment simulating rainfall striking the surface of a leaf showed that T. sessile foraging activity declined sharply under severe simulated rainfall conditions, whereas foraging activity of L. humile did not. Maintaining populations of honeydew-producing Hemiptera across broad climatic conditions may be one mechanism by which L. humile gains a competitive advantage over native ants occupying overlapping niches.

Effects of honeydew-producing hemipteran denial on local argentine ant distribution and boric acid bait performance

The Argentine ant is well known for its affinity for honeydew and is often associated with hemipteran outbreaks in agricultural and urban environments. It has been suggested that Argentine ants may be controlled by restricting access to honeydew, thereby forcing the ants to move or by encouraging increased liquid toxicant intake. We tested this possible control strategy by restricting Argentine ant access to the honeydew-producing terrapin scale within the canopy of red maple trees and monitoring ant numbers with pitfall traps and nest counts in the mulch around the tree base. Argentine ant nest numbers fell dramatically in the mulch around ant-excluded trees; however, there was no reduction in Argentine ant numbers caught in pitfalls around trees with or without canopy access. We added 0.5% boric acid bait stations at the base of the red maples and monitored bait consumption. Pitfall and nest counts were not affected by the addition of boric acid, although bait consumption was lower around ant-excluded trees, suggesting that restricting access to honeydew-producing Hemiptera did not enhance bait performance. We attribute this result to the increased distance Argentine ant workers had to trail from nest to bait station when not tending nearby terrapin scale. We suggest an alternative management strategy concentrating direct insecticidal control of Argentine ants around a few host plants infested with honeydew-producing Hemiptera by controlling Hemiptera in nearby host plants.

SNS-595 demonstrates clinical activity and dose-proportional pharmacokinetics (PK) in two phase I clinical studies

3062

Background: SNS-595 is a novel naphthyridine analog with broad and potent activity in preclinical models. Methods: SNS-595 was administered to patients (pts) with advanced solid cancers as an IV infusion over 10 minutes on 2 schedules: (A) qwk x3/1 week off, and (B) q3wks. Pt eligibility included refractory solid tumors and adequate organ function. Results: In study A, 20 patients (pts) were treated in 6 cohorts (dose range 3–24 mg/m2/wk). In study B, 41 pts were treated in 9 cohorts (dose range 3–75 mg/m2/wk). After the MTD in heavily pretreated (HP) pts was found, dose escalation in minimally pretreated (MP) pts was evaluated. The median ages were 60.5 yrs (A) and 59.5 yrs (B), sex 12F/8M (A), 16F/25M (B). All pts had a ECOG PS 0–2. Neutropenia was the dose limiting toxicity (DLT) for both studies. The MTD for A was 15 mg/m2 for HP and MP pts; the MTD for B was 48 mg/m2 for HP and 60 mg/m2 for MP pts. For both studies 2 pts had grade 4 thrombocytopenia; non-hematological toxicities were all grade 1/2. In A, pharmacokinetics (PK) were assessed on Days 1 and 15 (after the 1st and 3rd doses); exposure increased linearly over an 8-fold dose range (1.6–15 mcghr/mL), CL, Vss and T1/2 averaged 2 L/hr/m2, 49 L/m2, 18 hr, respectively, and did not change from Day 1 to 15. In B, PK were assessed on Day 1 after the 1st dose; exposure increased linearly over the 24-fold dose range (1.1–46 mcghr/mL), CL, Vss, and T1/2 averaged 2 L/hr/m2, 53 L/m2, and 21 hrs, respectively. For A, best responses were 4 SD (range 13–22 wks); for B, best responses were 1 PR and 12 SD (range 14–56 wks). Conclusion: SNS-595 was well tolerated and showed clinical activity with both qwk and q3wk dosing. The DLT was non-cumulative neutropenia. SNS-595 demonstrated remarkably predictable PK, with low inter-and intra-patient variability. Based on these data, phase 2 studies of SNS-595 as monotherapy are ongoing, and are planned in combination therapy.

[Table: see text]

Seroprevalence of Anaplasma phagocytophilum among Healthy Dogs and Horses in Israel

The presence of reacting antibodies to Anaplasma phagocytophilum has previously been demonstrated in Israel, both in humans and the golden jackal (Canis aureus syriacus). This study was undertaken to determine the seroprevalence of A. phagocytophilum antibodies in two additional potential hosts, domestic dogs and horses in order to investigate the possibility of exposure to the organism in Israel. Of 195 dogs tested, 9% were seroreactive with A. phagocytophilum antigen and 30% were seroreactive to Ehrlichia canis. Twenty-nine percent of the dogs seropositive for E. canis were also reactive to A. phagocytophilum. Two dogs had immunofluorescence antibody (IFA) antibody titres for A. phagocytophilum greater than E. canis. The equine serological survey (n = 300) revealed no seroreactive horses. The results presented in this study suggest that dogs in Israel could have been accidentally exposed to A. phagocytophilum, for example by ticks carried on migrating birds, however, the possibility of cross-reaction with E. canis should also be considered. In spite of the high prevalence of ticks on horses in Israel during the summer months, no evidence for exposure to A. phagocytophilum was apparent.

Linkage analysis for autism in a subset families with obsessive-compulsive behaviors: evidence for an autism susceptibility gene on chromosome 1 and further support for susceptibility genes on chromosome 6 and 19

Although there is considerable evidence for a strong genetic component to idiopathic autism, several genome-wide screens for susceptibility genes have been carried out with limited concordance of linked loci, reflecting numerous genes of weak effect and/or sample heterogeneity. In the current study, linkage analysis was carried out in a sample of 62 autism-affected relative pairs with more severe obsessive-compulsive behaviors, selected from a larger (n=115) set of autism-affected relative pairs as a means of reducing sample heterogeneity. Obsessive-compulsive behaviors were assessed using the Autism Diagnostic Interview-Revised (ADI-R). In the sample with more severe obsessive-compulsive behaviors, multipoint NPL scores above 2 were observed on chromosomes 1, 4, 5, 6, 10, 11 and 19, with the strongest evidence for linkage on chromosome 1 at the marker D1S1656, where the multipoint NPL score was 3.06, and the two-point NPL score was 3.21. In follow-up analyses, analyzing the subset of families (n=35) where the patients had the most severe obsessive-compulsive behaviors generated a multipoint NPL score of 2.76, and a two-point NPL score of 2.79, indicating that the bulk of evidence for linkage was derived from the families most severely affected with obsessive-compulsive behaviors. The data suggest that there is an autism susceptibility gene on chromosome 1 and provide further support for the presence of autism susceptibility genes on chromosomes 6 and 19.

Massive light-dependent cycling of inorganic carbon between oxygenic photosynthetic microorganisms and their surroundings

Membrane inlet mass spectrometry indicated massive light-dependent cycling of inorganic carbon between the medium and the cells of various phytoplankton species representing the main groups of aquatic primary producers. These included diatoms, symbiotic and free living dinoflagellates, a coccolithophorid, a green alga and filamentous and single cell cyanobacteria. These organisms could maintain an ambient CO(2) concentration substantially above or below that expected at chemical equilibrium with HCO(3) (-). The coccolithophorid Emiliania huxleyi shifted from net CO(2) uptake to net CO(2) efflux with rising light intensity. Differing responses of CO(2) uptake and CO(2) fixation to changing light intensity supported the notion that these two processes are not compulsorily linked. Simultaneous measurements of CO(2) and O(2) exchange and of the fluorescence parameters in Synechococcus sp. strain PCC 7942, showed that CO(2) uptake can serve as a sensitive probe of the energy status of the photosynthetic reaction centers. However, during transitions in light intensity, changes in CO(2) uptake did not accord with those expected from fluorescence change. Quantification of the net fluxes of CO(2), HCO(3) (-) and of photosynthesis at steady-state revealed that substantial HCO(3) (-) efflux accompanied CO(2) uptake and fixation in the case of 'CO(2) users'. On the other hand, 'HCO(3) (-) users' were characterized by a rate of net CO(2) uptake below that of CO(2) fixation. The results support the notion that entities associated with the CCM function not only in raising the CO(2) concentration at the site of Rubisco; they may also serve as a means of diminishing photodynamic damage by dissipating excess light energy.

Effects of aromatic cedar mulch on the Argentine ant and the odorous house ant (Hymenoptera: Formicidae)

In laboratory studies, the Argentine ant, Linepithema humile (Mayr), and the odorous house ant, Tapinoma sessile (Say), avoided aromatic cedar mulch as a nesting substrate. Both ant species were killed when confined with fresh aromatic cedar mulch in sealed containers. However, when confined with cedar mulch that had been aged outdoors for up to 140 d, mortality of L. humile was complete regardless of mulch age, whereas T. sessile mortality declined significantly over the mulch-aging period. Argentine ant susceptibility to aromatic cedar mulch was also greater than that of the odorous house ant when colonies were restricted to mulch in open trays. In addition, commercial aromatic cedar oil was lethal to both ant species. Our results suggest that aromatic cedar mulch may serve as an effective component of a comprehensive urban ant management program.

Affective instability and impulsivity in borderline personality and bipolar II disorders: similarities and differences

OBJECTIVES

many studies have reported a high degree of comorbidity between mood disorders, among which are bipolar disorders, and borderline personality disorder and some studies have suggested that these disorders are co-transmitted in families. However, few studies have compared personality traits between these disorders to determine whether there is a dimensional overlap between the two diagnoses. The aim of this study was to compare impulsivity, affective lability and intensity in patients with borderline personality and bipolar II disorder and in subjects with neither of these diagnoses.

METHODS

patients with borderline personality but without bipolar disorder (n=29), patients with bipolar II disorder without borderline personality but with other personality disorders (n=14), patients with both borderline personality and bipolar II disorder (n=12), and patients with neither borderline personality nor bipolar disorder but other personality disorders (OPD; n=93) were assessed using the Affective Lability Scale (ALS), the Affect Intensity Measure (AIM), the Buss-Durkee Hostility Inventory (BDHI) and the Barratt Impulsiveness Scale (BIS-7B).

RESULTS

borderline personality patients had significantly higher ALS total scores (P<0.05) and bipolar II patients tended to have higher ALS scores than patients with OPD (P<0.06). On one of the ALS subscales, the borderline patients displayed significant higher affective lability between euthymia and anger (P<0.002), whereas patients with bipolar II disorder displayed affective lability between euthymia and depression (P<0.04), or elation (P<0.01) or between depression and elation (P<0.01). A significant interaction between borderline personality and bipolar II disorder was observed for lability between anxiety and depression (P<0.01) with the ALS. High scores for impulsiveness (BISTOT, P<0.001) and hostility (BDHI, P<0.05) were obtained for borderline personality patients only and no significant interactions between diagnoses were observed. Only borderline personality patients tended to have higher affective intensity (AIM, P<0.07).

CONCLUSIONS

borderline personality disorder and bipolar II disorder appear to involve affective lability, which may account for the efficacy of mood stabilizers treatments in both disorders. However, our results suggest that borderline personality disorder cannot be viewed as an attenuated group of affective disorders.