Self-reported psychosis-like experiences in patients with mood disorders.

BACKGROUND: Self-reported psychosis-like experiences (PEs) may be common in patients with mood disorders, but their clinical correlates are not well known. We investigated their prevalence and relationships with self-reported symptoms of depression, mania, anxiety, borderline (BPD) and schizotypal (SPD) personality disorders among psychiatric patients with mood disorders. METHODS: The Community Assessment of Psychic Experiences (CAPE-42), Mood Disorder Questionnaire (MDQ), McLean Screening Instrument (MSI), The Beck Depressive Inventory (BDI), Overall Anxiety Severity and Impairment Scale (OASIS) and Schizotypal Personality Questionnaire-Brief form (SPQ-B) were filled in by patients with mood disorders (n=282) from specialized care. Correlation coefficients between total scores and individual items of CAPE-42 and BDI, SPQ-B, MSI and MDQ were estimated. Hierarchical multivariate regression analysis was conducted to examine factors influencing the frequency of self-reported PE. RESULTS: PEs are common in patients with mood disorders. The "frequency of positive symptoms" score of CAPE-42 correlated strongly with total score of SPQ-B (rho=0.63; P<0.001) and moderately with total scores of BDI, MDQ, OASIS and MSI (rho varied from 0.37 to 0.56; P<0.001). Individual items of CAPE-42 correlated moderately with specific items of BDI, MDQ, SPQ-B and MSI (rφ varied from 0.2 to 0.5; P<0.001). Symptoms of anxiety, mania or hypomania and BPD were significant predictors of the "frequency of positive symptoms" score of CAPE-42. CONCLUSIONS: Several, state- and trait-related factors may underlie self-reported PEs among mood disorder patients. These include cognitive-perceptual distortions of SPD; distrustfulness, identity disturbance, dissociative and affective symptoms of BPD; and cognitive biases related to depressive or manic symptoms.

Habitat connectivity and in-stream vegetation control temporal variability of benthic invertebrate communities.

One of the key challenges to understanding patterns of ß diversity is to disentangle deterministic patterns from stochastic ones. Stochastic processes may mask the influence of deterministic factors on community dynamics, hindering identification of the mechanisms causing variation in community composition. We studied temporal ß diversity (among-year dissimilarity) of macroinvertebrate communities in near-pristine boreal streams across 14 years. To assess whether the observed ß diversity deviates from that expected by chance, and to identify processes (deterministic vs. stochastic) through which different explanatory factors affect community variability, we used a null model approach. We observed that at the majority of sites temporal ß diversity was low indicating high community stability. When stochastic variation was unaccounted for, connectivity was the only variable explaining temporal ß diversity, with weakly connected sites exhibiting higher community variability through time. After accounting for stochastic effects, connectivity lost importance, suggesting that it was related to temporal ß diversity via random colonization processes. Instead, ß diversity was best explained by in-stream vegetation, community variability decreasing with increasing bryophyte cover. These results highlight the potential of stochastic factors to dampen the influence of deterministic processes, affecting our ability to understand and predict changes in biological communities through time.

Level of functioning, perceived work ability, and work status among psychiatric patients with major mental disorders.

BACKGROUND: Major mental disorders are highly disabling conditions that result in substantial socioeconomic burden. Subjective and objective measures of functioning or ability to work, their concordance, or risk factors for them may differ between disorders. METHODS: Self-reported level of functioning, perceived work ability, and current work status were evaluated among psychiatric care patients with schizophrenia or schizoaffective disorder (SSA, n=113), bipolar disorder (BD, n=99), or depressive disorder (DD, n=188) within the Helsinki University Psychiatric Consortium Study. Correlates of functional impairment, subjective work disability, and occupational status were investigated using regression analysis. RESULTS: DD patients reported the highest and SSA patients the lowest perceived functional impairment. Depressive symptoms in all diagnostic groups and anxiety in SSA and BD groups were significantly associated with disability. Only 5.3% of SSA patients versus 29.3% or 33.0% of BD or DD patients, respectively, were currently working. About half of all patients reported subjective work disability. Objective work status and perceived disability correlated strongly among BD and DD patients, but not among SSA patients. Work status was associated with number of hospitalizations, and perceived work disability with current depressive symptoms. CONCLUSIONS: Psychiatric care patients commonly end up outside the labour force. However, while among patients with mood disorders objective and subjective indicators of ability to work are largely concordant, among those with schizophrenia or schizoaffective disorder they are commonly contradictory. Among all groups, perceived functional impairment and work disability are coloured by current depressive symptoms, but objective work status reflects illness course, particularly preceding psychiatric hospitalizations.

Anxiety symptoms in a major mood and schizophrenia spectrum disorders.

BACKGROUND: Comorbid anxiety symptoms and disorders are present in many psychiatric disorders, but methodological variations render comparisons of their frequency and intensity difficult. Furthermore, whether risk factors for comorbid anxiety symptoms are similar in patients with mood disorders and schizophrenia spectrum disorders remains unclear. METHODS: The Overall Anxiety Severity and Impairment Scale (OASIS) was used to measure anxiety symptoms in psychiatric care patients with schizophrenia or schizoaffective disorder (SSA, n=113), bipolar disorder (BD, n=99), or depressive disorder (DD, n=188) in the Helsinki University Psychiatric Consortium Study. Bivariate correlations and multivariate linear regression models were used to examine associations of depressive symptoms, neuroticism, early psychological trauma and distress, self-efficacy, symptoms of borderline personality disorder, and attachment style with anxiety symptoms in the three diagnostic groups. RESULTS: Frequent or constant anxiety was reported by 40.2% of SSA, 51.5% of BD, and 55.6% of DD patients; it was described as severe or extreme by 43.8%, 41.4%, and 41.2% of these patients, respectively. SSA patients were significantly less anxious (P=0.010) and less often avoided anxiety-provoking situations (P=0.009) than the other patients. In regression analyses, OASIS was associated with high neuroticism, symptoms of depression and borderline personality disorder and low self-efficacy in all patients, and with early trauma in patients with mood disorders. CONCLUSIONS: Comorbid anxiety symptoms are ubiquitous among psychiatric patients with mood or schizophrenia spectrum disorders, and in almost half of them, reportedly severe. Anxiety symptoms appear to be strongly related to both concurrent depressive symptoms and personality characteristics, regardless of principal diagnosis.

Spectral mapping of heat transfer mechanisms at liquid-solid interfaces.

Thermal transport through liquid-solid interfaces plays an important role in many chemical and biological processes, and better understanding of liquid-solid energy transfer is expected to enable improving the efficiency of thermally driven applications. We determine the spectral distribution of thermal current at liquid-solid interfaces from nonequilibrium molecular dynamics, delivering a detailed picture of the contributions of different vibrational modes to liquid-solid energy transfer. Our results show that surface modes located at the Brillouin zone edge and polarized along the liquid-solid surface normal play a crucial role in liquid-solid energy transfer. Strong liquid-solid adhesion allows also for the coupling of in-plane polarized modes in the solid with the liquid, enhancing the heat-transfer rate and enabling efficient energy transfer up to the cutoff frequency of the solid. Our results provide fundamental understanding of the energy-transfer mechanisms in liquid-solid systems and enable detailed investigations of energy transfer between, e.g., water and organic molecules.

Self-reported symptoms of schizotypal and borderline personality disorder in patients with mood disorders.

BACKGROUND: Distinguishing between symptoms of schizotypal (SPD) and borderline personality disorders (BPD) is often difficult due to their partial overlap and frequent co-occurrence. We investigated correlations in self-reported symptoms of SPD and BPD in questionnaires at the levels of both total scores and individual items, examining overlapping dimensions. METHODS: Two questionnaires, the McLean Screening Instrument (MSI) for BPD and the Schizotypal Personality Questionnaire Brief (SPQ-B) for SPD, were filled in by patients with mood disorders (n=282) from specialized psychiatric care in a study of the Helsinki University Psychiatric Consortium. Correlation coefficients between total scores and individual items of the MSI and SPQ-B were estimated. Multivariate regression analysis (MRA) was conducted to examine the relationships between SPQ-B and MSI. RESULTS: The Spearman's correlation between total scores of the MSI and SPQ-B was strong (rho=0.616, P<0.005). Items of MSI reflecting disrupted relatedness and affective dysregulation correlated moderately (rφ varied between 0.2 and 0.4, P<0.005) with items of SPQ. Items of MSI reflecting behavioural dysregulation correlated only weakly with items of SPQ. In MRA, depressive symptoms, sex and MSI were significant predictors of SPQ-B score, whereas symptoms of anxiety, age and SPQ-B were significant predictors of MSI score. CONCLUSIONS: Items reflecting cognitive-perceptual distortions and affective symptoms of BPD appear to overlap with disorganized and cognitive-perceptual symptoms of SPD. Symptoms of depression may aggravate self-reported features of SPQ-B, and symptoms of anxiety features of MSI. Symptoms of behavioural dysregulation of BPD and interpersonal deficits of SPQ appear to be non-overlapping.

Thermal balance and quantum heat transport in nanostructures thermalized by local Langevin heat baths.

Modeling of thermal transport in practical nanostructures requires making tradeoffs between the size of the system and the completeness of the model. We study quantum heat transfer in a self-consistent thermal bath setup consisting of two lead regions connected by a center region. Atoms both in the leads and in the center region are coupled to quantum Langevin heat baths that mimic the damping and dephasing of phonon waves by anharmonic scattering. This approach treats the leads and the center region on the same footing and thereby allows for a simple and physically transparent thermalization of the system, enabling also perfect acoustic matching between the leads and the center region. Increasing the strength of the coupling reduces the mean-free path of phonons and gradually shifts phonon transport from ballistic regime to diffusive regime. In the center region, the bath temperatures are determined self-consistently from the requirement of zero net energy exchange between the local heat bath and each atom. By solving the stochastic equations of motion in frequency space and averaging over noise using the general fluctuation-dissipation relation derived by Dhar and Roy [J. Stat. Phys. 125, 801 (2006)], we derive the formula for thermal current, which contains the Caroli formula for phonon transmission function and reduces to the Landauer-Büttiker formula in the limit of vanishing coupling to local heat baths. We prove that the bath temperatures measure local kinetic energy and can, therefore, be interpreted as true atomic temperatures. In a setup where phonon reflections are eliminated, the Boltzmann transport equation under gray approximation with full phonon dispersion is shown to be equivalent to the self-consistent heat bath model. We also study thermal transport through two-dimensional constrictions in square lattice and graphene and discuss the differences between the exact solution and linear approximations.

Thermal conduction and interface effects in nanoscale Fermi-Pasta-Ulam conductors.

We perform classical nonequilibrium molecular dynamics simulations to calculate heat flow through a microscopic junction connecting two larger reservoirs. In contrast to earlier papers, we also include the reservoirs in the simulated region to study the effect of the bulk-nanostructure interfaces and the bulk conductance. The scalar Fermi-Pasta-Ulam (FPU) model is used to describe the effects of anharmonic interactions in a simple manner. The temperature profile close to the junction in the low-temperature limit is shown to exhibit strong directional features that fade out when temperature increases. Simulating both the FPU chain and the two bulk regions is also shown to eliminate the nonmonotonous temperature variations found for simpler geometries and models. We show that, with sufficiently large reservoirs, the temperature profile in the chain does not depend on the details of thermalization used at the boundaries.

Divergent timing of egg-laying may maintain life history polymorphism in potentially multivoltine insects in seasonal environments.

The length of the favourable season determines voltinism in insect populations. In some insects, there is variation in fecundity and timing of reproduction among females. If the length of the favourable season does not allow all offspring to develop into adults without diapause, the benefits of high early fecundity may outweigh the associated cost of low lifetime fecundity. We tested this by exploring mating frequencies of Pieris napi females along a latitudinal gradient in different generations. Pieris napi is a bivoltine butterfly, and genetically polyandrous females enjoy higher lifetime fecundity than monandrous ones. Polyandry is, however, coupled with a relatively low early fecundity. We found that monandrous females are more likely to produce an additional generation than polyandrous ones under conditions that allow production of only a partial summer generation. Monandrous females were also the first to emerge and slightly over-represented in the summer generation under conditions that allow the development of a complete summer generation. Further, a stochastic model shows that variation in the timing of reproduction between strategies is sufficient to explain the observed patterns. Thus, seasonality may counter-select against polyandry, or more generally against low early reproductive rate, and promote maintenance of polymorphism in life history strategies.

Pollution-induced community tolerance and functional redundancy in a decomposer food web in metal-stressed soil.

Pollution may lead to the development of pollution-induced community tolerance (PICT) in a stressed community. We studied the presence of PICT in soil food webs using soil microcosms. Soil microcosms containing soil invertebrates and microbes were collected from polluted and unpolluted areas and exposed to a range of soil zinc concentrations. A pine seedling was planted in each microcosm to measure the effects of the origin of the community and Zn pollution on above-ground plant production. The effects of the treatments on nutrient content in the soil were also measured. The diversity of soil microarthropods and the soil's mineral nutrient content were low at the Zn-polluted site. We did not observe an increasing Zn tolerance among the soil organisms in the polluted soil. However, low population growth rates of soil invertebrates from the polluted site may indicate the deleterious effects on fitness of long-lasting pollution. In the soil from the nonpolluted site, Zn additions caused changes in the invertebrate food web structure. These changes were explained by the good physiological condition of the animals and their insensitivity to Zn. The fact that the food web structure in soil from the polluted site did not change can be used as a rough indicator of PICT. Structural stability is presumed by the lack of Zn-sensitive species at this site and the inability of populations to acclimate by altering their growth or reproduction patterns in response to changing soil conditions. Although microbial-based soil decomposer systems may have a high functional redundancy, our results indicate that metal stress at the polluted site exceeds the tolerance limits of the system. As a consequence, ecosystem function at this site is endangered. This study also shows that the evolution of metal tolerance by soil decomposer organisms may not be a common reaction to soil pollution, although changes of population and community structure indicated severe metal stress on organisms.

Composite implant composed of hydroxyapatite and bone morphogenetic protein in the healing of a canine ulnar defect.

BACKGROUND AND AIMS: Hydroxyapatite (HA) has been considered as a carrier material for bone morphogenetic proteins (BMP). The aim of this study was to evaluate the capacity of a composite implant of HA and native bovine BMP to heal a 2 cm segmental defect in the canine ulna. MATERIALS AND METHODS: A composite HA+BMP implant was compared with plain HA implants and cortical autografts. The fixation was accomplished with an intramedullary Kirschner wire. The bone union was evaluated by X-rays taken at operation and after 3, 6, 9, 12, 16, 25, 35 weeks and by histology and mechanical torsion tests. RESULTS: HA implants were not able to produce complete bone union even with BMP. There was some bridging between the implant and the bone in the defects treated with either plain HA or HA+BMP implant, the bridging being slightly more pronounced with HA+BMP. The autografts showed a significantly better capacity to heal the defect. The HA implant did not resorb markedly during the study. There was no significant difference in mechanical strength between the HA and HA+BMP groups. CONCLUSIONS: HA was not an adequate bone substitute material in this study model, and BMP was not able to enhance sufficiently the poor capacity of HA to heal canine ulnar defects.

Functional analysis of novel mutations in y(+)LAT-1 amino acid transporter gene causing lysinuric protein intolerance (LPI).

Lysinuric protein intolerance (LPI; MIM 222700) is an autosomal recessive disorder characterized by defective transport of the cationic amino acids lysine, arginine and ornithine at the basolateral membrane of the polar epithelial cells in the intestine and renal tubules, and by hyperammonemia after high-protein meals. LPI is caused by mutations in the SLC7A7 (solute carrier family 7, member 7) gene encoding y(+)LAT-1 (y(+)L amino acid transporter-1), which co-induces together with 4F2 heavy chain (4F2hc) system y(+)L in Xenopus oocytes. All Finnish LPI patients share the same founder mutation 1181-2A-->T (LPI(Fin)) not found in LPI patients elsewhere. Mutation screening of 20 non-Finnish LPI patients revealed 10 novel mutations: four deletions, two missense mutations, two nonsense mutations, a splice site mutation and a tandem duplication. Five LPI mutations (L334R, G54V, 1291delCTTT, 1548delC and LPI(Fin)) were studied functionally. All mutant proteins failed to co-induce amino acid transport activity when expressed with 4F2hc in Xenopus oocytes. Immunostaining experiments revealed that frameshift mutants 1291delCTTT, 1548delC and LPI(Fin)remained intracellular on expression with 4F2hc. In contrast, the missense mutants L334R and G54V reached the oocyte plasma membrane when co-expressed with 4F2hc, demonstrating that they are transport-inactivating mutations. This finding, together with the strong degree of conservation among all members of this family of amino acid transporters, indicates that residues L334 and G54 play a crucial role in the function of the y(+)LAT-1 transporter.

Extraction and characterization of native canine bone morphogenetic protein (cBMP) qualified with osteoinductivity.

Bone morphogenetic protein (BMP) was extracted from canine bone matrix, partially purified and tested for osteoinductivity. A radiographically and histologically detectable ectopic bone formation was induced by 6.0 mg canine (cBMP) in muscle pouch of BALB mouse at 21 days post implantation. Characterization of the cBMP preparation by a gel filtration chromatography defined that the material consisted of proteins or protein complexes with molecular weights from 4 to 120 kD. Isoelectric focusing showed that the molecules were acidic with isoelectric points of 4.6-5.6.

[The use of bone morphogenetic proteins in delayed fracture healing, pseudoarthrosis and in ulna osteotomy carried out because of elbow joint diseases]. / Die Anwendung knochenmorphogenetischen Proteins bei verzögerter Frakturheilung, Pseudarthrose und bei wegen Ellbogengelenkerkrankungen durchgeführter Ulnaosteotomie.

This study deals with the application of bone morphogenetic protein (BMP) as an osteoinductive factor in the treatment of fractures and elbow disease in the dog. Partially purified canine bone morphogenetic protein (cBMP) was used in the repair of a delayed union fracture and a pseudoarthrosis. The cBMP was applied in Biocoral and Tricalciumphosphate carriers using a subcortical grafting method. Two dogs suffering from incongruence and subluxation of the elbow joint were treated with a partially purified bone morphogenetic protein of moose bone origin placed in the gap produced by ulnar osteotomy.

Conifer aphids in an air-polluted environment. I. Aphid density, growth and accumulation of sulphur and nitrogen by scots pine and Norway spruce seedlings.

The population dynamics of conifer aphids on pine and spruce seedlings growing in plastic pots were studied along a gradient from a pulp mill emitting mainly SO(2). At five locations, two apterous females of the grey pine aphid (Schizolachnus pineti L.) feeding on needles, and two apterous females of the spruce shoot aphid (Cinara pilicornis Hartig) feeding on the stem, were transferred to the leader shoot of 10 pine and spruce seedlings, respectively. The sulphur concentrations of the transplanted lichen Hypogymnia physodes (L.) Nyl. and needles of conifer seedlings were significantly increased in the close vicinity of the pulp mill. On pine seedlings, the numbers of S. pineti developed similarly at all study sites. However, in mid-July, the numbers of aphids started to decline near the emission source. In June, C. pilicornis reproduction on spruce was significantly faster at 0.2 and 0.5 km from the pollution source than at the more distant sites, but there was a rapid decline in aphid numbers in July. A negative correlation was observed between the numbers of C. pilicornis during the population peak in late June and the final length of the current year's leader shoot of spruce seedlings. Leader shoot growth of spruce seedlings infested by aphids was positively correlated with the distance from the pulp mill. There were no clear responses to pollution level in parasitization or predation rates of the aphids. The results suggest that all conifer aphids are not good indicators of pollution impact on conifers around a pollution source. There is a general agreement with the earlier reports that Cinara spp. numbers have a positive response to air pollution, especially to SO(2). This is probably due to promoted growth of nymphal aphids on the host plants suffering from pollution. However, high levels of air pollution may also cause rapid collapse of aphid populations. S. pineti, which lives on foliage, did not have a positive response to increased SO(2) levels.

Conifer aphids in an air-polluted environment. II. Host plant quality.

Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) seedlings were transported to five forest sites at increasing distances from a pulp mill emitting mainly SO(2). Levels of compounds which may have nutritional or defensive value for aphids on pine and spruce seedlings were studied. Glucose and fructose concentrations were significantly increased in pine and spruce needles near the pulp mill. There were no changes in sucrose and starch concentrations. In pine shoots, total free amino acid concentration and the concentrations of ornithine, lysine, histidine and arginine were significantly negatively correlated with the distance from the pulp mill, while in spruce only the individual amino acids glycine, ornithine, lysine and histidine showed a significant negative correlation with distance. There were no changes in total phenolic, catechin, total monoterpene and total resin acid concentrations. However, in pine seedlings monoterpenes beta-pinene and sabinene and in spruce seedlings resin acid palustric acid were significantly correlated with the distance from the pulp mill. The results indicate that SO(2) disturbs carbohydrate metabolism in spruce and pine seedlings. The elevated concentrations of arginine may be the result of the combinations of SO(2), NO(3) and NH(3) emissions of the pulp mill. The emissions did not have any impact on total amounts of defensive substances in trees. Thus, the possible susceptibility of conifers to herbivores appears to be due to changes in nutritive value rather than to reduced chemical resistance.

A method for facilitating the use of algae growing on tree trunks as bioindicators of air quality.

The abundance of epiphytic green algae has been observed to correlate strongly with air quality in several studies. In contrast to lichens, the abundance of green algae is difficult to measure accurately by visual observation. A new method based on photography and digital image processing was developed to estimate the chlorophyll content of algae growing on the bark of pine. Calibration data for the method was collected from polluted areas by spectrophotometric analysis of chlorophyll density.

Effect of exposure to fluoride, nitrogen compounds and SO2 on the numbers of spruce shoot aphids on Norway spruce seedlings.

Development of spruce shoot aphid (Cinara pilicornis Hartig) populations was monitored in natural and artificial infestations of Norway spruce (Picea abies Karst.) seedlings, exposed to air pollutants in an experimental field. The pollutants, applied both singly and in mixtures, were gaseous sulphur dioxide, NaF (30 mg l-1 F) and Ca(NO3)2 or (NH4)2SO4 in aqueous solutions (200 mg l-1 N). Aphid numbers on 10 seedlings in each treatment and two control plots were counted at 2-week intervals. At the beginning of the experiment aphid numbers did not differ between treatments. Aphid populations peaked in late June and early July. All the pollutants and their combinations significantly increased the numbers of aphids per seedling. Four apterous females were transferred to spruce seedlings which were growing in containers in the same plots. After 4-5 weeks aphid numbers were significantly higher in the fluoride treatment and in the combined treatment of fluoride, nitrogen and SO2. The pollution treatments did not have a significant effect on shoot growth. Concentrations of F and S in needles were higher in treatments involving these pollutants. There were no significant differences in the concentrations of free amino acids in shoot stems between control and fluoride treatment. However, the relatively low concentration of arginine in the F treatment at the end of the growing season might indicate disturbances in the nitrogen metabolism of spruce seedlings.