Copper Transfer from Cu–Aβ to Human Serum Albumin Inhibits Aggregation,Radical Production and Reduces Aβ Toxicity

Amyloid‐β peptides (Aβ) and the protein human serum albumin (HSA) interact in vivo. They are both localised in the blood plasma and in the cerebrospinal fluid. Among other functions, HSA is involved in the transport of the essential metal copper. Complexes between Aβ and copper ions have been proposed to be an aberrant interaction implicated in the development of Alzheimer's disease, where Cu is involved in Aβ aggregation and production of reactive oxygen species (ROS). In the present work, we studied copper‐exchange reaction between Aβ and HSA or the tetrapeptide DAHK (N‐terminal Cu‐binding domain of HSA) and the consequence of this exchange on Aβ‐induced ROS production and cell toxicity. The following results were obtained: 1) HSA and DAHK removed Cu^II from Aβ rapidly and stoichiometrically, 2) HSA and DAHK were able to decrease Cu‐induced aggregation of Aβ, 3) HSA and DAHK suppressed the catalytic HO^. production in vitro and ROS production in neuroblastoma cells generated by Cu–Aβ and ascorbate, 4) HSA and DAHK were able to rescue these cells from the toxicity of Cu–Aβ with ascorbate, 5) DAHK was more potent in ROS suppression and restoration of neuroblastoma cell viability than HSA, in correlation with an easier reduction of Cu^II–HSA than Cu–DAHK by ascorbate, in vitro. Our data suggest that HSA is able to decrease aberrant Cu^II–Aβ interaction. The repercussion of the competition between HSA and Aβ to bind Cu in the blood and brain and its relation to Alzheimer's disease are discussed.     

Determination of the heat transfer coefficient from short‐shots studies and precise simulation of microinjection molding

The filling process of a micro‐cavity was analyzed by modeling the compressible filling stage by using pressure‐dependent viscosity and adjusted heat transfer coefficients. Experimental filling studies were carried out at the same time on an accurately controlled microinjection molding machine. On the basis of the relationship between the injection pressure and the filling degree, essential factors for the quality of the simulation can be identified. It can be shown that the flow behavior of the melt in a micro‐cavity with a high aspect ratio is extremely dependent on the melt compressibility in the injection cylinder. This phenomenon needs to be considered in the simulation to predict an accurate flow rate. The heat transfer coefficient between the melt and the mold wall that was determined by the reverse engineering varies significantly even during the filling stage. With increasing injection speed and increasing cavity thickness, the heat transfer coefficient decreases. It is believed that the level of the cavity pressure is responsible for the resulting heat transfer between the polymer and the mold. A pressure‐dependent model for the heat transfer coefficient would be able to significantly improve the quality of the process simulation. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers     

Evolution of ophthalmic and electrophysiological findings in identical twin sisters with the carbohydrate deficient glycoprotein syndrome type 1 over a period of 14 years

AIMS: To evaluate the evolution of ocular and electroretinographic findings in identical twin sisters with the carbohydrate deficient glycoprotein (CDG) syndrome over a period of 14 years. METHODS: Both girls underwent a clinical ophthalmic examination with funduscopy and an electrophysiological assessment with recording of flash electroretinogram (FERG) at the age of 4 years and 18 years RESULTS: On ophthalmic examination at the age of 4 years an alternating convergent squint and a saccadic pursuit was diagnosed. In both, vision was 6/9 bilaterally. Fundus examination showed normal optic discs, narrow blood vessels, and a mild irregular pigmentation in the periphery. In one girl the FERG showed a recognisable a, b1, and b2-wave with reduced amplitude to less than 40% of the normal. In the other girl the reduction in amplitude was still more obvious, but for the white flash a small b1-wave was still present. At the age of 18 vision had remained 6/9 in both eyes. Funduscopy showed pink optic discs, moderately narrowed blood vessels, and bony spicule pigmentary deposits in the mid periphery. The adapto ERG, performed in identical conditions at 18 years of age, showed a completely extinguished trace for both eyes. CONCLUSIONS: Despite progressive deterioration of ERG findings good central vision was preserved over 14 years.     

Improving the social behavior and peer acceptance of rejected boys: Effects of social skill training with instructions and prohibitions.

Thirty-two boys who were rejected by their peers in Grades 1–3 were identified on the basis of negative sociometric nominations and negative social behavior. They were randomly assigned to one of four treatment conditions: (a) instructions to promote positive social behavior, (b) prohibitions to reduce negative social behavior, (c) a combination of instructions and prohibitions, or (d) no treatment. Interventions were applied during 10 half-hour school play sessions. Behavioral observations and peer and teacher ratings were collected prior to treatment, immediately after treatment, and at a follow-up assessment 6 weeks after treatment. Additional peer and teacher ratings were collected at a 1-year follow-up. Prohibitions combined with a response cost for negative behaviors resulted in immediate and stable declines in negative behavior and led to temporary increases in positive responses received from peers. Instructions and the reinforcement of specific social skills promoted sustained positive peer interactions 6 weeks after treatment. Only the combination of instructions and prohibitions led to improved sociometric ratings from nontarget treatment partners. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Downward comparison, prejudice, and evaluations of others: Effects of self-esteem and threat.

In two studies, we explored the effects of trait self-esteem and threats to the self-concept on evaluations of others. In Study 1, subjects high, moderate, and low in self-esteem received either success, failure, or no feedback on a test and later evaluated three pairs of targets: ingroups and outgroups based on a minimal intergroup manipulation, those who scored above average and those who scored below average on the test, and themselves and the average college student. Study 2 explored the effects of self-esteem and threat on ingroup favoritism in a real-world setting, campus sororities. Together, the results of these studies indicate that individuals high in self-esteem, but not those low in self-esteem, respond to threats to the self-concept by derogating outgroups relative to the ingroup when the group boundaries have evaluative implications. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Malpractice risks in the treatment of dangerous patients.

Reviews areas of special vulnerability and the legal penalties that may befall psychotherapists who improperly manage dangerous patients (DPs). General rules of malpractice are discussed. While ethical and professional principles are important in the management of DPs, emphasis is placed on legal principles. The potential pitfalls include the failure to report suspected child abuse, abandonment of DPs, the duty to refer, the duty to protect 3rd parties, the failure to commit, the negligent release of DPs from inpatient facilities, and the inadequate treatment of suicidal patients. Leading cases illustrate the legal points. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Feminist identity and feminist therapy behaviors of women psychotherapists.

Investigated whether (1) feminist identity development for women therapists was related to their use of feminist therapy behaviors (FTBs) and (2) feminist identity development and use of FTBs for women therapists were related to self-identification as a feminist therapist. 153 women psychologists (aged 30–77 yrs) were administered a women's issues in therapy questionnaire, which included a short version of the Feminist Identity Scale (FIS; K. M. Rickard, 1989, 1990). Ss were categorized into stages of feminine identity development according to their scores on 4 subscales of the FIS: Passive-Acceptance (PA), Revelation (REV), Embeddedness (EMB), and Synthesis (SYN). Ss scoring high on SYN and REV, and low on PA, reported greater use of FTBs; scores on the EMB were not related to the use of FTBs. All 4 subscales were predictive of women therapists who self-identified as feminist therapists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Maintenance of grip-induced muscle tension: A behavioral marker of schizophrenia.

A grip-induced muscle tension maintenance task distinguished between schizophrenic patients, regardless of medication or hospitalization status, and both normals and controls with affective (unipolar and bipolar) disorders. Unaffected 1st-degree relatives of schizophrenic patients also showed a grip deficit. Coupling the grip task with a visual discrimination task that divided attention through instruction or reinforcement contingency increased grip error times for all groups. No group differences appeared on the discrimination task, regardless of difficulty level, and the tone used to provide corrective feedback was not implicated in the grip deficit. The results suggest that the grip task is tapping, in a systematic and reliable manner, a motor-control abnormality that may be useful as a behavioral marker of schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development and assessment of methods for detecting dementia using the human electroencephalogram

This paper makes an outline case for the need for a low-cost, easy to administer method for detecting dementia within the growing at risk population. It proposes two methods for electroencephalogram (EEG) analysis for detecting dementia that could fulfil such a need. The paper describes a fractal dimension-based method for analyzing the EEG waveforms of subjects with dementia and reports on an assessment which demonstrates that an appropriate fractal dimension measure could achieve 67% sensitivity to probable Alzheimer's disease (as suggested by clinical psychometric testing and EEG findings) with a specificity of 99.9%. An alternative method based on the probability density function of the zero-crossing intervals is shown to achieve 78% sensitivity to probable Alzheimer's disease and an estimated sensitivity to probable Vascular (or mixed) dementia of 35% (as suggested by clinical psychometric testing and EEG findings) with a specificity of 99.9%. This compares well with other studies, reported by the American Academy of Neurology, which typically provide a sensitivity of 81% and specificity of 70%. The EEG recordings used to assess these methods included artefacts and had no a priori selection of elements "suitable for analysis." This approach gives a good prediction of the usefulness of the methods, as they would be used in practice. A total of 39 patients (30 probable Alzheimer's Disease, six Vascular Dementia and three mixed dementia) and 42 healthy volunteers were involved in the study. However, although results from the preliminary evaluation of the methods are promising, there is a need for a more extensive study to validate the methods using EEGs from a larger and more varied patient cohorts with neuroimaging results, to exclude other causes and cognitive scores to correlate results with severity of cognitive status.     

A Sensitive Analytical Method for Quantifying Petromyzonol Sulfate in Water as a Potential Tool for Population Monitoring of the Southern Pouched Lamprey, Geotria Australis, in New Zealand Streams

The migratory southern pouched lamprey, Geotria australis, is a culturally important fish native to New Zealand. Anecdotal evidence suggests that populations of G. australis have declined from historic levels, and presently, this species is rare in many New Zealand rivers and streams. Migratory sea lamprey (Petromyzon marinus) use a pheromone mixture to locate suitable spawning sites. This mixture is comprised of three steroids: petromyzonol sulfate (PS), petromyzonamine disulfate (PADS), and petromyzosterol disulfate (PSDS). We examined the migratory pheromone mixture released by G. australis ammocetes and found that they excrete predominantly PS. PADS has been detected on some occasions in low concentrations, and PSDS either is not released, or is released in extremely low concentrations. By using a recently developed sensitive mass spectrometry method, we compared passive sampling techniques against more traditional active water sampling as methods for estimating lamprey populations in local streams. Passive sampling provided quantitative data for PS from all sites surveyed, with uptake rates of 0.3 to 45.7 pg/day observed. Conversely, active sampling returned only one positive result out of 19 samples, and with a method detection limit of 2.5 × 10^-14 M, this suggests that concentrations of PS in these streams are either extremely low or variable. The combination of passive sampling and triple quadrupole mass spectrometry is a promising tool for monitoring of G. australis in New Zealand streams.