Assessing microplastic exposure of large marine filter-feeders.

Large filter-feeding animals are potential sentinels for understanding the extent of microplastic pollution, as their mode of foraging and prey mean they are continuously sampling the environment. However, there is considerable uncertainty about the total and mode of exposure (environmental vs trophic). Here, we explore microplastic exposure and ingestion by baleen whales feeding year-round in coastal Auckland waters, New Zealand. Plastic and DNA were extracted concurrently from whale scat, with 32 ± 24 (mean ± SD, n = 21) microplastics per 6 g scat sample detected. Using a novel stochastic simulation modeling incorporating new and previously published DNA diet information, we extrapolate this to total microplastic exposure levels of 24,028 (95% CI: 2119, 69,270) microplastics per mouthful of prey, or 3,408,002 microplastics (95% CI: 295,810, 10,031,370) per day, substantially higher than previous estimates for large filter-feeding animals. Critically, we find that the total exposure is four orders of magnitude more than expected from microplastic measurements of local coastal surface waters. This suggests that trophic transfer, rather than environmental exposure, is the predominant mode of exposure of large filter feeders for microplastic pollution. Measuring plastic concentration from the environment alone significantly underestimates exposure levels, an important consideration for future risk assessment studies.

Ocean-wide genomic variation in Gray's beaked whales, Mesoplodon grayi.

The deep oceans of the Southern Hemisphere are home to several elusive and poorly studied marine megafauna. In the absence of robust observational data for these species, genetic data can aid inferences on population connectivity, demography and ecology. A previous investigation of genetic diversity and population structure in Gray's beaked whale (Mesoplodon grayi) from Western Australia and New Zealand found high levels of mtDNA diversity, no geographic structure and stable demographic history. To further investigate phylogeographic and demographic patterns across their range, we generated complete mitochondrial and partial nuclear genomes of 16 of the individuals previously analysed and included additional samples from South Africa (n = 2) and South Australia (n = 4), greatly expanding the spatial range of genomic data for the species. Gray's beaked whales are highly elusive and rarely observed, and our data represents a unique and geographically broad dataset. We find relatively high levels of diversity in the mitochondrial genome, despite an absence of population structure at the mitochondrial and nuclear level. Demographic analyses suggest these whales existed at stable levels over at least the past 1.1 million years, with an approximately twofold increase in female effective population size approximately 250 thousand years ago, coinciding with a period of increased Southern Ocean productivity, sea surface temperature and a potential expansion of suitable habitat. Our results suggest that Gray's beaked whales are likely to be resilient to near-future ecosystem changes, facilitating their conservation. Our study demonstrates the utility of low-effort shotgun sequencing in providing ecological information on highly elusive species.

Multi-locus DNA metabarcoding of zooplankton communities and scat reveal trophic interactions of a generalist predator.

To understand the ecosystem dynamics that underpin the year-round presence of a large generalist consumer, the Bryde's whale (Balaenoptera edeni brydei), we use a DNA metabarcoding approach and systematic zooplankton surveys to investigate seasonal and regional changes in zooplankton communities and if whale diet reflects such changes. Twenty-four zooplankton community samples were collected from three regions throughout the Hauraki Gulf, New Zealand, over two temperature regimes (warm and cool seasons), as well as 20 samples of opportunistically collected Bryde's whale scat. Multi-locus DNA barcode libraries were constructed from 18S and COI gene fragments, representing a trade-off between identification and resolution of metazoan taxa. Zooplankton community OTU occurrence and relative read abundance showed regional and seasonal differences based on permutational analyses of variance in both DNA barcodes, with significant changes in biodiversity indices linked to season in COI only. In contrast, we did not find evidence that Bryde's whale diet shows seasonal or regional trends, but instead indicated clear prey preferences for krill-like crustaceans, copepods, salps and ray-finned fishes independent of prey availability. The year-round presence of Bryde's whales in the Hauraki Gulf is likely associated with the patterns of distribution and abundance of these key prey items.

Incorporating non-equilibrium dynamics into demographic history inferences of a migratory marine species.

Understanding how dispersal and gene flow link geographically separated the populations over evolutionary history is challenging, particularly in migratory marine species. In southern right whales (SRWs, Eubalaena australis), patterns of genetic diversity are likely influenced by the glacial climate cycle and recent history of whaling. Here we use a dataset of mitochondrial DNA (mtDNA) sequences (n = 1327) and nuclear markers (17 microsatellite loci, n = 222) from major wintering grounds to investigate circumpolar population structure, historical demography and effective population size. Analyses of nuclear genetic variation identify two population clusters that correspond to the South Atlantic and Indo-Pacific ocean basins that have similar effective breeder estimates. In contrast, all wintering grounds show significant differentiation for mtDNA, but no sex-biased dispersal was detected using the microsatellite genotypes. An approximate Bayesian computation (ABC) approach with microsatellite markers compared the scenarios with gene flow through time, or isolation and secondary contact between ocean basins, while modelling declines in abundance linked to whaling. Secondary-contact scenarios yield the highest posterior probabilities, implying that populations in different ocean basins were largely isolated and came into secondary contact within the last 25,000 years, but the role of whaling in changes in genetic diversity and gene flow over recent generations could not be resolved. We hypothesise that these findings are driven by factors that promote isolation, such as female philopatry, and factors that could promote dispersal, such as oceanographic changes. These findings highlight the application of ABC approaches to infer the connectivity in mobile species with complex population histories and, currently, low levels of differentiation.

Exploring spatial and temporal trends in the soundscape of an ecologically significant embayment.

The Hauraki Gulf, a shallow embayment in north-eastern New Zealand, provides an interesting environment for ecological soundscape research. It is situated on a tectonic plate boundary, contains one of the busiest ports in the southern hemisphere and is home to a diverse range of soniferous animals. The underwater soundscape was monitored for spatial and temporal trends at six different listening stations using passive acoustic recorders. The RMS sound pressure level of ambient sound (50-24,000 Hz) at the six listening stations was similar, ranging from 90-110 dB re 1 µPa throughout the recording period. Biophony had distinct temporal patterns and biological choruses of urchins were significantly correlated to temperature. Geophony and biophony followed the acoustic niche hypothesis, where each sound exhibited both temporal and frequency partitioning. Vessel passage sound were identified in 1.9-35.2% of recordings from the different listening stations. Vessel sound recorded in the Hauraki Gulf has the potential to mask concurrent geophony and biophony, sounds that may be important to marine life. This study provides a baseline of ambient sound, useful for future management strategies in shallow embayments where anthropogenic pressure is likewise increasing.

A case report of zinc phosphide poisoning: complicated by acute renal failure and tubulo interstitial nephritis.

BACKGROUND: Run Rat® is a rodenticide widely used against small mammals. It comprises of a minimum of 32% zinc phosphide which is highly toxic in acute exposures to humans. It may be consumed accidentally or intentionally. It enters the body via skin, respiratory and gastrointestinal tracts. Zinc phosphide is hydrolyzed by the gastric acid and is transformed into phosphine gas. Phosphine is a respiratory toxin that inhibits cytochrome C oxidase system resulting in renal failure and liver failure. CASE PRESENTATION: A 35 year old Sri Lankan female presented following ingestion of 2.5 g of Run Rat®, which is a branded preparation of zinc phosphide, resulting in 61 mg/kg poison load. She developed severe acute kidney injury with acute tubular necrosis, subnephrotic ranged proteinuria and tubulointerstitial nephritis for which she underwent haemodialysis three times along with other measures of resuscitation. She also developed elevated liver enzymes with hyperblirubinaemia, hypoalbuminaemia, acute pancreatitis and mild myocarditis. She improved with supportive therapy over a period of 3 weeks. CONCLUSION: Run Rat® is a commonly used rodenticide and the toxic effects are mediated through conversion of phosphide to phosphine gas. The majority of the deaths had occurred in the first 12 to 24 h and the main causes identified are refractory hypotension and arrhythmias. The late deaths (beyond 24 h) had been commonly due to adult respiratory distress syndrome, liver and renal failure. The outcome is poorer with delayed presentation, development of coagulopathy, hyperglycaemia and multiorgan failure with elevated liver enzymes. In our patient, Zinc phosphide poisoning caused severe acute kidney injury, abnormal liver profile, pancreatitis and possible myocarditis. The patient improved with repeated haemodialysis. The renal biopsy revealed acute tubulointerstitial nephritis with acute tubular necrosis. In tropical countries, the rural population engaged in agriculture has easier access to the compound, as it is available at a lower cost. Furthermore, the lack of an antidote and advanced resuscitative measures such as inotropic supportive therapy and renal replacement facilities at most of the peripheral hospitals pose a major challenge in providing timely interventions to prevent deaths.

Bucking the trend: genetic analysis reveals high diversity, large population size and low differentiation in a deep ocean cetacean.

Understanding the genetic structure of a population is essential to its conservation and management. We report the level of genetic diversity and determine the population structure of a cryptic deep ocean cetacean, the Gray's beaked whale (Mesoplodon grayi). We analysed 530 bp of mitochondrial control region and 12 microsatellite loci from 94 individuals stranded around New Zealand and Australia. The samples cover a large area of the species distribution (~6000 km) and were collected over a 22-year period. We show high genetic diversity (h=0.933-0.987, π=0.763-0.996% and Rs=4.22-4.37, He=0.624-0.675), and, in contrast to other cetaceans, we found a complete lack of genetic structure in both maternally and biparentally inherited markers. The oceanic habitats around New Zealand are diverse with extremely deep waters, seamounts and submarine canyons that are suitable for Gray's beaked whales and their prey. We propose that the abundance of this rich habitat has promoted genetic homogeneity in this species. Furthermore, it has been suggested that the lack of beaked whale sightings is the result of their low abundance, but this is in contrast to our estimates of female effective population size based on mitochondrial data. In conclusion, the high diversity and lack of genetic structure can be explained by a historically large population size, in combination with no known exploitation, few apparent behavioural barriers and abundant habitat.

Neuropsychological assessment of cognitive function in chronic alcohol-dependent patients and patients with Alzheimer's disease.

BACKGROUND: Heavy and chronic alcohol dependence and Alzheimer's disease may share some neuropsychological characteristics. PATIENTS AND METHODS: The pattern of neuropsychological characteristics of 33 alcohol-dependent patients who reported memory disturbances were evaluated and compared to the neuropsychological performance of 38 patients with mild-stage Alzheimer's disease and 73 healthy subjects, serving as controls. Alcohol-dependent patients were examined with tools concerning the pattern of alcohol abuse and problems related to alcohol consumption. All groups completed a full battery of neuropsychological tests for the assessment of cognitive functions, such as different kinds of memory, attention, executive function etc. RESULTS: Alcohol-dependent patients fared worse compared to the control subjects in every test used. The comparison of alcohol-dependent patients versus patients with Alzheimer's disease showed that the latter are much more burdened, as far as cognition is concerned, in all aspects of memory. CONCLUSION: Alcohol-dependent patients, even if they are not demented, have mild cognitive impairment in all domains of cognition (memory and frontal functions) in comparison with controls which performed within the norms. Verbal fluency, working memory and frontal functions were impaired at the same degree in alcohol-dependent patients and in patients with Alzheimer's disease. Memory problems were more pronounced in Alzheimer's disease patients.

Illness behaviour in neurological inpatients with psychiatric morbidity.

OBJECTIVE: The aim of the present study was to examine whether psychiatric morbidity can influence the type of illness behaviour of neurological inpatients. METHODS: For this purpose, we compared neurological inpatients with and without psychiatric disorders (DSM-IIIR criteria) for the seven scales of Illness Behaviour Questionnaire (IBQ) and searched for possible differences between the two patient subgroups. RESULTS: Of the 105 neurological inpatients who participated in the study, 54 (51.4%) were diagnosed as having some type of psychiatric disorder. These patients scored significantly higher than patients without psychiatric morbidity in the scale of Irritability. A suggestive trend for higher scores in the scales of Hypochondriasis, Disease Conviction, and Affective Disturbance, and significantly lower score in the scale of Denial, in patients with psychiatric morbidity, were also found. CONCLUSION: The present study has shown that neurological inpatients with psychiatric morbidity tend to develop more intense illness behaviour than those without. The effect of psychiatric morbidity on certain components of illness behaviour in neurological patients can be taken into account when therapeutic strategies are planned.

Challenges of implementing intervention research in persons with dementia: example of a glider swing intervention.

Intervention studies for persons with dementia present many challenges. This article describes challenges encountered in conducting a glider swing intervention study for persons with dementia and the strategies used to manage the problems encountered. The overall purpose of a quasi-experimental study was to explore the effects of a glider swing intervention on emotions, relaxation, and aggressive behaviors in nursing home residents with dementia. Suggestions for investigators conducting intervention studies for persons with dementia are provided.

A glider swing intervention for people with dementia.

The soothing, repetitive movement of rocking and swinging is well known to anyone who has enjoyed a porch swing or rocking chair. Positive effects of rocking have been reported. However, investigations on its effect in people with dementia are limited. The purposes of this quasi-experimental, repeated-measures design study were to measure the effects of a glider swing on emotions, relaxation, and aggressive behaviors in a group of nursing home residents with dementia (n = 30). Data were obtained during a 5-day baseline phase, a 10-day intervention phase, and a 5-day posttreatment phase. Subjects were placed on the glider for 20 minutes each day during the intervention phase. The results of the study indicate that the glider intervention significantly improved emotions and relaxation. The most noted changes were found after 10 minutes of swinging. However, no differences were found in aggressive behaviors.

Evolution of cortical activation during recovery from corticospinal tract infarction.

BACKGROUND AND PURPOSE: Recovery from hemiparesis due to corticospinal tract infarction is well documented, but the mechanism of recovery is unknown. Functional MRI (fMRI) provides a means of identifying focal brain activity related to movement of a paretic hand. Although prior studies have suggested that supplementary motor regions in the ipsilesional and contralesional hemisphere play a role in recovery, little is known about the time course of cortical activation in these regions as recovery proceeds. METHODS: Eight patients with first-ever corticospinal tract lacunes causing hemiparesis had serial fMRIs within the first few days after stroke and at 3 to 6 months. Six healthy subjects were used as controls. Statistically significant voxels during a finger-thumb opposition task were identified with an automated image processing program. An index of ipsilateral versus contralateral activity was used to compare relative contributions of the 2 hemispheres to motor function in the acute and chronic phases after stroke. RESULTS: Controls showed expected activation in the contralateral sensorimotor cortex (SMC), premotor, and supplementary motor areas. Stroke patients differed from control patients in showing greater activation in the ipsilateral SMC, ipsilateral posterior parietal, and bilateral prefrontal regions. Compared with the nonparetic hand, the ratio of contralateral to ipsilateral SMC activity during movement of the paretic hand increased significantly over time as the paretic hand regained function. CONCLUSIONS: The evolution of activation in the SMC from early contralesional activity to late ipsilesional activity suggests that a dynamic bihemispheric reorganization of motor networks occurs during recovery from hemiparesis.

Mitogenic response of osteoblast cells to prostate-specific antigen suggests an activation of latent TGF-beta and a proteolytic modulation of cell adhesion receptors.

During studies of mitogens in prostate, PSA quantities as low as 2.5 ng/mL caused cultured osteoblast cells to proliferate beyond controls (p = 0.05). Investigation of this novel mitogenicity suggested the use of several mechanisms by PSA, namely: 1) the activation of latent hTGF-beta in PC-3 conditioned medium, PSA treated conditioned medium stimulated DNA uptake in UMR-106 cells to 78% of acid treated conditioned medium, while DNA incorporation was less than controls with anti-hTGF-beta neutralizing IgG; and 2) the proteolytic modulation of cell surface receptors with temporary contact inhibition, PSA significantly stimulated cell detachment while hTGF-beta enhanced cell attachment of confluent Saos-2 cells above controls. Clinically, these results suggest that PSA may provide a mechanism for both tumor spread and the osteoblastic metastasis so common to prostate cancer.

Serum level of cryptic tumor antigens in breast cancer patients as determined by two monoclonal antibodies (M85/F36) and its comparison with CA 15-3.

An enzyme immunoassay system that measures cryptic epitopes on breast cancer mucinlike antigens (BCM-EIA) was evaluated in a double-blind manner in sera from 58 normal blood donors, 36 sex- and age-matched controls, 36 patients with benign breast diseases, and 47 patients with breast cancer. Two murine monoclonal antibodies, M85 (IgM) as the solid-phase and F36/22 (IgG3) as the probe, were used in the configuration of the assay kit. The assay additionally utilized neuraminidase to remove terminal sialic acid from carbohydrate side-chains to expose cryptic epitopes that were masked in serum specimens. BCM-EIA monoclonal assay from the normal healthy blood donors resulted in 17.34 +/- 7.04 units/ml (mean +/- 1 S.D.) with an upper normal cutoff of 31.4 units/ml. The distributions of serum BCM in the sex- and age-matched controls (17.77 +/- 11.17) and benign breast diseases (14.34 +/- 11.46) were similar to that of normal blood donors. A mean value of 66.04 units/ml and 27.74 units/ml was obtained from breast cancer patients with active disease and without evidence of disease, respectively, a level much greater than those of normals, controls, and benign breast diseases. Simultaneous analysis of CA 15-3, a putative breast tumor marker, in the normal donors and breast cancer patients revealed correlation regression of (CA 15-3) = 0.876 (BCM) + 1.972, r = 0.856; and (CA 15-3) = 0.66 (BCM) + 16.094, r = 0.730, respectively. These data showed that there is a statistically significant correlation of CA 15-3 and BCM in normal blood donors' specimens.(ABSTRACT TRUNCATED AT 250 WORDS)

Human tissue polypeptide antigen in breast cancer.

Serum tissue polypeptide antigen (TPA) and plasma carcinoembryonic antigen (CEA) were simultaneously measured in 108 patients with breast cancer, in 40 healthy women, and in 26 women with benign breast disease. TPA levels were elevated (0.09 microgram/ml or higher) in 53% of 19 patients with primary breast cancer, and CEA levels were elevated (2.5 ng/ml) in 21%. Among 67 patients with metastatic breast cancer, TPA and CEA levels were increased in 70% and 61%, respectively. TPA was positive in 13% and CEA in 8% of the healthy women. CEA levels were not elevated in patients with benign breast disease, but levels of TPA were elevated in 27% of those studied. Elevation of TPA levels was more frequent in patients with visceral metastasis having higher values of the test results. Among 22 women with breast cancer who had no apparent cancer recurrence, TPA levels were elevated in 12 and CEA levels in 6. In another group of 39 patients with metastatic breast cancer who received palliative therapy, a limited correlation was noted between the clinical course of the disease and changes in TPA and CEA values measured in linear fashion. Thus TPA appeared to be equal to CEA as a tumor marker in most areas analyzed.