Multiscale and Extended Retrieval of Associative Memory Structures in a Cortical Model of Local-Global Inhibition Balance.

Inhibitory neurons take on many forms and functions. How this diversity contributes to memory function is not completely known. Previous formal studies indicate inhibition differentiated by local and global connectivity in associative memory networks functions to rescale the level of retrieval of excitatory assemblies. However, such studies lack biological details such as a distinction between types of neurons (excitatory and inhibitory), unrealistic connection schemas, and nonsparse assemblies. In this study, we present a rate-based cortical model where neurons are distinguished (as excitatory, local inhibitory, or global inhibitory), connected more realistically, and where memory items correspond to sparse excitatory assemblies. We use this model to study how local-global inhibition balance can alter memory retrieval in associative memory structures, including naturalistic and artificial structures. Experimental studies have reported inhibitory neurons and their subtypes uniquely respond to specific stimuli and can form sophisticated, joint excitatory-inhibitory assemblies. Our model suggests such joint assemblies, as well as a distribution and rebalancing of overall inhibition between two inhibitory subpopulations, one connected to excitatory assemblies locally and the other connected globally, can quadruple the range of retrieval across related memories. We identify a possible functional role for local-global inhibitory balance to, in the context of choice or preference of relationships, permit and maintain a broader range of memory items when local inhibition is dominant and conversely consolidate and strengthen a smaller range of memory items when global inhibition is dominant. This model, while still theoretical, therefore highlights a potentially biologically-plausible and behaviorally-useful function of inhibitory diversity in memory.

Geographic distribution, large-scale spatial structure and diversity of parasitoids of the seed-feeding beetle Acanthoscelides macrophthalmus.

Bruchine beetles are highly host-specific seed feeders during the larval stage. Although some specific parasitoid families have been recorded attacking bruchine beetles, most studies have been done at small spatial scales. Therefore, the current knowledge about the diversity and the geographic distribution of parasitoid species parasitizing bruchines is scarce, especially at a wide geographic area that extends over large distances through a latitudinal cline (i.e. large-scale spatial structure). The present study determined the species richness and evenness of parasitoids attacking the bruchine beetle Acanthoscelides macrophthalmus feeding on Leucaena leucocephala seeds, examined their geographic distribution, and characterized the large-scale spatial structure in parasitoid species composition. A total of 1420 parasitoids (all Hymenoptera) belonging to four families, five subfamilies and eight species were collected (genera: Horismenus, Paracrias, Urosigalphus, Stenocorse, Chryseida, Eupelmus). Most parasitoid species showed wide spatial distribution, high evenness in species abundance and the species richness estimators were close to stabilization (approximately eight species). Overall, greater similarity was observed in the species composition of plant populations near to each other than those farther apart, revealing a large-scale spatial structure in parasitoid species composition.

Feasibility of dialectical behavior therapy with suicidal and self-harming adolescents with multi-problems: training, adherence, and retention.

We evaluated the feasibility of DBT training, adherence, and retention preparing for a randomized controlled trial of Dialectical Behavior Therapy (DBT) adapted for Norwegian adolescents engaging in self-harming behavior and diagnosed with features of borderline personality disorder. Therapists were intensively trained and evaluated for adherence. Adherence scores, treatment retention, and present and previous self-harm were assessed. Twenty-seven patients were included (mean age 15.7 years), all of them with recent self-harming behaviors and at least 3 features of Borderline Personality Disorder. Therapists were adherent and 21 (78%) patients completed the whole treatment. Three subjects reported self-harm at the end of treatment, and urges to self-harm decreased. At follow up, 7 of 10 subjects reported no self-harm. DBT was found to be well accepted and feasible. Randomized controlled trials are required to test the effectiveness of DBT for adolescents.

TAP-deficient human iPS cell-derived myeloid cell lines as unlimited cell source for dendritic cell-like antigen-presenting cells.

We previously reported a method to generate dendritic cell (DC)-like antigen-presenting cells (APC) from human induced pluripotent stem (iPS) cells. However, the method is relatively complicated and laborious. In the current study, we attempted to establish a method through which we could obtain a large number of functional APC with a simple procedure. We transduced iPS cell-derived CD11b(+) myeloid cells with genes associated with proliferative or anti-senescence effects, enabling the cells to propagate for more than 4 months in a macrophage colony-stimulating factor (M-CSF)-dependent manner while retaining their capacity to differentiate into functional APC. We named these iPS cell-derived proliferating myeloid cells 'iPS-ML', and the iPS-ML-derived APC 'ML-DC'. In addition, we generated TAP2-deficient iPS cell clones by zinc finger nuclease-aided targeted gene disruption. TAP2-deficient iPS cells and iPS-ML avoided recognition by pre-activated allo-reactive CD8(+) T cells. TAP2-deficient ML-DC expressing exogenously introduced HLA-A2 genes stimulated HLA-A2-restricted MART-1-specific CD8(+) T cells obtained from HLA-A2-positive allogeneic donors, resulting in generation of MART-1-specific cytotoxic T lymphocyte (CTL) lines. TAP-deficient iPS-ML introduced with various HLA class I genes may serve as an unlimited source of APC for vaccination therapy. If administered into allogeneic patients, ML-DC with appropriate genetic modifications may survive long enough to stimulate antigen-specific CTL and, after that, be completely eliminated. Based on the present study, we propose an APC-producing system that is simple, safe and applicable to all patients irrespective of their HLA types.

MDMA use is associated with increased spatial BOLD fMRI visual cortex activation in human MDMA users.

Previous animal studies have demonstrated that 3,4-methylenedioxymethamphetamine (MDMA) exposure causes serotonin axotomy that is greatest in occipital cortex (including primary visual cortex) where serotonergic axons innervate neurons and blood vessels. Human MDMA users have altered serotonergic function and reduced gray matter density in occipital cortex. The fMRI BOLD method is potentially sensitive to both the neuronal and vascular consequences of MDMA-induced serotonin toxicity. To test the hypothesis that MDMA users have altered visual system function, we used the fMRI BOLD technique to assay visual cortical activation after photic stimulation in a group of adult MDMA users. Because MDMA users worldwide are polydrug users and therefore difficult to match to comparison groups in terms of polydrug exposure, we conducted a primary within-group analysis examining the correlation between lifetime episodes of MDMA exposure and measures of visual cortical activation. The within-group correlational analysis in the MDMA user group revealed that the degree of prior MDMA exposure was significantly positively correlated with the number of activated pixels for photic stimulation (r=0.582, p=0.007). A secondary between-group comparison of MDMA users with non-MDMA users found overall greater levels of polydrug exposure in the MDMA user cohort but no significant differences in visual cortical activation measures between the two groups. Additional research is needed to clarify the origin and significance of the current findings.

Epidural metastasis in chemoresistant Wilms' tumor with perilobar nephroblastomatosis.

An 8-year-old boy with vertebral and epidural metastases was diagnosed with Wilms' tumor associated with perilobar nephroblastomatosis (NB) based on histologic examination. During combined chemotherapy with vincristine, actinomycin D, doxorubicin, and cyclophosphamide (NWTS-3 J protocol), a rapid increase in tumor size was observed. The treatment was replaced with etoposide and carboplatin (JET regimen). A transient response was sustained for 5 months during this chemotherapy. However, regrowth of the tumor was observed and the patient died 11 months after the initial chemotherapy.

[Health service for physicians. What do physicians want--form and substance?]. / En helsetjeneste for leger. Hva øonsker legene selv--form og innhold?

In 1991, a special health service for doctors was started in Rogaland county. Three years later this service was evaluated via a questionnaire. Two thirds of 109 doctors were very satisfied, and only one was dissatisfied with this health service. The results show a need for both psychosocial and somatic health examinations for doctors.

Sequelae one year after meningococcal disease.

Of 99 consecutive patients with meningococcal disease, 6 died during the acute stage. The 93 survivors were examined one year after hospitalization. 21 (40%) of the adults and 6 (15%) of the children had definite sequelae, and an additional 27% and 11% possible sequelae. 6 adults (12%) and 1 child (2%) had definite neurological sequelae. Electroencephalography (EEG) abnormalities were observed in 7 adults (14%) and 2 children (5%). Epileptogenic activity was present in 3 of these, but none had experienced seizures. 8 adults (19%) and 5 children (14%) had sensorineural hearing loss or impaired vestibular function. Cerebral computerized tomography (CT) scan showed definite and possible abnormalities in 1 (3%) and 6 (18%), respectively, of the 34 patients tested. Neuropsychological tests were performed in 9 patients, 2 of these showed definite impairment. The frequency of neurological abnormalities was higher than in many previous studies, probably reflecting the more comprehensive examinations performed in the present study. However, only 3 patients had serious sequelae. The results suggest that the occurrence of sequelae after meningococcal disease is related to the severity of the acute disease. This may explain the higher rate of sequelae in adults, who have a higher proportion of seriously ill patients. The presence of meningitis is not required for the occurrence of neurological sequelae.

Structural identification of an epitope of antigenic factor 5 in mannans of Candida albicans NIH B-792 (serotype B) and J-1012 (serotype A) as beta-1,2-linked oligomannosyl residues.

In previous articles, we reported the presence of phosphate-bound beta-1,2-linked oligomannosyl residues in the mannans of strains of Candida albicans serotypes A and B and Candida stellatoidea. To identify the antigenic factor corresponding to this type of oligomannosyl residue, a relationship between chemical structure and antigenic specificity in the mannans of C. albicans NIH B-792 (serotype B, B-strain) and C. albicans J-1012 (serotype A, J-strain) was investigated by using a combination of two-dimensional 1H nuclear magnetic resonance spectroscopy of H-1, H-2, and H-5 regions in the mannans and an enzyme-linked immunosorbent assay that employed concanavalin A-coated microtiter plates. It was shown in the present 1H nuclear magnetic resonance study that an examination of chemical shifts not only in the H-1 region but also in the H-5 region was useful for the quantitative determination of the phosphate-bound beta-1,2-linked oligomannosyl residues. In the enzyme-linked immunosorbent assay using concanavalin A-coated plates, it was revealed that, of factor sera 1, 4, and 5, only factor serum 5 showed a reactivity proportional to the densities of the beta-1,2-linked oligomannosyl residues of the mannan subfractions of different phosphate contents that had been prepared from the bulk B-strain mannan by DEAE-Sephadex chromatography. The above results indicate that the phosphate-bound beta-1,2-linked oligomannosyl residues, Manp beta 1----(2Manp beta 1----)n2Man (n = 0-5), correspond to antigenic factor 5.

[Health services for physicians in Rogaland. A questionnaire study]. / Helsetjeneste for leger i Rogaland. En spørreskjemaundersøkelse.

In order to investigate the need for a health service for doctors a questionnaire was mailed to all doctors in Rogaland county. 84% of the respondents were in favour of such a service. It is necessary not only to provide a general medical examination but to focus also on work-related and psychosocial factors.

[Suicide investigation--a psychological autopsy]. / Selvmordsgjennomgang--psykologisk autopsi.

The most disastrous complication for a psychiatric team occurs when the patient commits suicide. The reactions of the personnel involved with the patient are similar to the reactions of the bereaved: denial, guilt and shame, aggression and accusation, relief. By psychological autopsy we mean a structured group meeting where all the factors leading up to the suicide are discussed and the reactions of the personnel ventilated. This is different from psychological debriefing, where the primary aim is to ventilate the reactions of the involved personnel without analyzing what went wrong. The article describes how psychological autopsy has been conducted for more than 15 years at the psychiatric ward in the Central Hospital in Stavanger, Norway.

[Tissue polypeptide antigen in serum and tissue in patients with lung cancer].

To evaluate the significance of TPA (tissue polypeptide antigen) as a tumor marker for lung cancer, the present studies were designed to measure serum TPA levels as well as TPA contents in tumor tissues in patients with lung cancer. Average serum TPA levels (203.5 +/- 180.5 U/l, mean +/- SD) in 76 patients with lung cancer (30 squamous cell carcinoma, 38 adenocarcinoma, 8 small cell carcinoma) were significantly higher than those in pneumonia (83.3 +/- 42.7 U/l, n = 13), pulmonary tuberculosis (87.6 +/- 36.3 U/l, n = 16), and normal controls (46.8 +/- 23.7 U/l, n = 28). There was no significant difference in TPA levels according to the histological type of lung cancer. Comparing respective stage cases, statistically significant differences were observed in serum TPA levels between normal controls and stage 1, stage 1 and stage 3, and in stage 3 and stage 4, suggesting a gradual increase in TPA levels accompanying the progress of the lung cancer. In patients with 12 squamous cell carcinoma and 9 adenocarcinoma, the TPA levels in carcinoma tissues and non-tumor invaded lung tissues were 115.2 +/- 187.7 and 148.9 +/- 223.3 U/mg protein, indicating no significant difference in carcinoma and normal tissues. There was definite correlation between serum TPA levels and TPA contents in carcinoma tissues. No significant relationship, however, was observed between serum TPA levels and TPA contents in tissue not invaded by tumor. These results suggest that serum TPA levels reflect the tumor burden in patients with lung cancer. In conclusion, the determination of TPA in blood is useful for the diagnosis of lung cancer.

Reduced performance in tests of memory and visual abstraction in seamen exposed to industrial solvents.

Eighty-five seamen exposed to a variety of organic solvents and hydrocarbon compounds during their work on chemical tankers were compared with 59 unexposed seamen. Visual memory, auditory memory and visual abstraction were examined 14 days or more after the last solvent exposure. Multivariate analyses were performed to control the effects of confounding factors such as age, alcohol consumption, smoking, cerebral concussions and educational level. Significant correlations were found between increasing solvent exposure and poor results in tests of auditory memory and visual abstraction. These results indicate adverse psychological effects caused by chronic organic solvent exposure.