Atypical attentional filtering of visual information in youth with chromosome 22q11.2 deletion syndrome as indexed by event-related potentials

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Attentional control measured in 22q youth and typically developing control group.

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Differences in attentional control indexed by N2pc and PD event-related potentials.

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22q youth exhibited sustained focus on distractor cues and reduced suppression.

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No relationships between attentional control and psychosis-proneness in 22q youth.

Background

Youth with chromosome 22q11.2 deletion syndrome (22q) face one of the highest genetic risk factors for the development of schizophrenia. Previous research suggests impairments in attentional control and potential interactions with elevated anxiety and reduced adaptive functioning may increase the risk for developing psychosis in this population. Here, we examined how variations in attentional control relate to the presence or severity of psychosis-proneness symptoms in these individuals.

Methods

To achieve this, we measured attentional control in youth (12–18 years) with 22q (N = 35) compared to a typically developing group (N = 45), using a flanker task (the Distractor Target task) while measuring neural activity with event-related potentials.

Results

Similar to previous findings observed in people with schizophrenia, greater attentional capture by, and reduced suppression of, non-target flanker stimuli characterized participants with 22q and was indexed by the N2pc (N2-posterior-contralateral) and P_D (distractor positivity) components. Although we observed no relationships between these components and measures of psychosis-proneness in youth with 22q, these individuals endorsed a relatively low incidence of positive symptoms overall.

Conclusions

Our results provide neural evidence of an attentional control impairment in youth with 22q that suggests these individuals experience sustained attentional focus on irrelevant information and reduced suppression of distracting stimuli in their environment. Impairments in attentional control might be a valid biomarker of the potential to develop attenuated positive symptoms or frank psychosis in high-risk individuals long before the age at which such symptoms typically arise. The evaluation of such a hypothesis, and the preventive potential for the putative biomarker, should be the focus of future studies.

Brain free water alterations in first-episode psychosis: a longitudinal analysis of diagnosis, course of illness, and medication effects

BACKGROUND

Multiple lines of evidence suggest the presence of altered neuroimmune processes in patients with schizophrenia (Sz) and severe mood disorders. Recent studies using a novel free water diffusion tensor imaging (FW DTI) approach, proposed as a putative biomarker of neuroinflammation, atrophy, or edema, have shown significantly increased FW in patients with Sz. However no studies to date have investigated the longitudinal stability of FW alterations during the early course of psychosis, nor have studies focused separately on FE psychosis patients with Sz or bipolar disorder (BD) with psychotic features.

METHODS

The current study included 188 participants who underwent diffusion magnetic resonance imaging scanning at baseline. Sixty-four participants underwent follow-up rescanning after 12 months. DTI-based alterations in patients were calculated using voxelwise tract-based spatial statistics and region of interest analyses.

RESULTS

Patients with FE psychosis, both Sz and BD, exhibited increased FW at illness onset which remained unchanged over the 12-month follow-up period. Preliminary analyses suggested that antipsychotic medication exposure was associated with higher FW in gray matter that reached significance in the BD group. Higher FW in white matter correlated with negative symptom severity.

CONCLUSIONS

Our results support the presence of elevated FW at the onset of psychosis in both Sz and BD, which remains stable during the early course of the illness, with no evidence of either progression or remission.

Effects of aging and life-long moderate calorie restriction on IL-15 signaling in the rat white adipose tissue

OBJECTIVE

Phosphorylation of insulin receptor substrate (IRS) 1 by tumor necrosis factor alpha (TNF-α) has been implicated as a factor contributing to insulin resistance. Administration of IL-15 reduces adipose tissue deposition in young rats and stimulates secretion of adiponectin, an insulin sensitizing hormone that inhibits the production and activity of TNF-α. We aimed at investigating the effects of age life-long moderate calorie restriction (CR) on IL-15 and TNF-α signaling in rat white adipose tissue (WAT).

MATERIALS AND METHODS

Thirty-six 8-month-old, 18-month-old, and 29-month-old male Fischer344´Brown Norway F1 rats (6 per group) were either fed ad libitum (AL) or calorie restricted by 40%. The serum levels of IL-15 and IL-15 receptor α-chain (IL-15Rα) were increased by CR controls regardless of age. An opposite pattern was detected in WAT. In addition, CR reduced gene expression of TNF-α and cytosolic IRS1 serine phosphorylation in WAT, independently from age.

RESULTS

IL-15 signaling in WAT is increased over the course of aging in AL rats compared with CR rodents. Protein levels of IL-15Rα are greater in WAT of AL than in CR rats independently from age. This adaptation was paralleled by increased IRS1 phosphorylation through TNF-α-mediated insulin resistance. Adiponectin decreased at old age in AL rats, while no changes were evident in CR rats across age groups.

CONCLUSIONS

IL-15 signaling could therefore represent a potential target for interventions to counteract metabolic alterations and the deterioration of body composition during aging.

The birth experience and subsequent maternal caregiving attitudes and behavior: a birth cohort study

Optimal maternal caregiving is critical for children's healthy development, yet quality of maternal caregiving may be influenced by a negative birth experience. We examined whether the birth experience was associated with maternal caregiving attitudes and behavior throughout the first year. We conducted secondary analysis of the Avon Longitudinal Study of Parents and Children birth cohort on perinatal data. The birth experience was assessed using self-report data on level of support in labor. Maternal caregiving variables were self-report maternal attitudes at one and eight postnatal months, and observed maternal behavior at 12 postnatal months. Data were analyzed using multivariable logistic regression models adjusting for critical covariates at one (N = 4389), eight (N = 4580), and 12 (N = 842) postnatal months. Feeling supported in labor was associated with a report of "immediately falling in love" with one's baby after birth, surveyed at 1 month (adjusted OR 1.41 [95% CI 1.20-1.65]), and with more positive parenting scores at 8 months (adjusted OR 1.56 [95% CI 1.36-1.79]), but not with more positive observed maternal behavior at 12 months. Additional risk factors were identified. Our findings suggest that we may be able to modify the risk of poor postnatal maternal caregiving by supporting women in labor and facilitating a positive birth experience.

Memory and cognition in schizophrenia

Episodic memory deficits are consistently documented as a core aspect of cognitive dysfunction in schizophrenia patients, present from the onset of the illness and strongly associated with functional disability. Over the past decade, research using approaches from experimental cognitive neuroscience revealed disproportionate episodic memory impairments in schizophrenia (Sz) under high cognitive demand relational encoding conditions and relatively unimpaired performance under item-specific encoding conditions. These specific deficits in component processes of episodic memory reflect impaired activation and connectivity within specific elements of frontal-medial temporal lobe circuits, with a central role for the dorsolateral prefrontal cortex (DLPFC), relatively intact function of ventrolateral prefrontal cortex and variable results in the hippocampus. We propose that memory deficits can be understood within the broader context of cognitive deficits in Sz, where impaired DLPFC-related cognitive control has a broad impact across multiple cognitive domains. The therapeutic implications of these findings are discussed.

Behavioral and epigenetic consequences of oxytocin treatment at birth

Oxytocin is used in approximately half of all births in the United States during labor induction and/or augmentation. However, the effects of maternal oxytocin administration on offspring development have not been fully characterized. Here, we used the socially monogamous prairie vole to examine the hypothesis that oxytocin exposure at birth can have long-term developmental consequences. Maternally administered oxytocin increased methylation of the oxytocin receptor (Oxtr) in the fetal brain. As adults, oxytocin-exposed voles were more gregarious, with increased alloparental caregiving toward pups and increased close social contact with other adults. Cross-fostering indicated that these effects were the result of direct action on the offspring, rather than indirect effects via postnatal changes in maternal behavior. Male oxytocin-exposed offspring had increased oxytocin receptor density and expression in the brain as adults. These results show that long-term effects of perinatal oxytocin may be mediated by an epigenetic mechanism.

Impact of schizophrenia on anterior and posterior hippocampus during memory for complex scenes

Objectives

Hippocampal dysfunction has been proposed as a mechanism for memory deficits in schizophrenia. Available evidence suggests that the anterior and posterior hippocampus could be differentially affected. Accordingly, we used fMRI to test the hypothesis that activity in posterior hippocampus is disproportionately reduced in schizophrenia, particularly during spatial memory retrieval.

Methods

26 healthy participants and 24 patients with schizophrenia from the UC Davis Early Psychosis Program were studied while fMRI was acquired on a 3 Tesla Siemens scanner. During encoding, participants were oriented to critical items through questions about item features (e.g., “Does the lamp have a square shade?”) or spatial location (e.g., “Is the lamp on the table next to the couch?”). At test, participants determined whether scenes were changed or unchanged. fMRI analyses contrasted activation in a priori regions of interest (ROI) in anterior and posterior hippocampus during correct recognition of item changes and spatial changes.

Results

As predicted, patients with schizophrenia exhibited reduced activation in the posterior hippocampus during detection of spatial changes but not during detection of item changes. Unexpectedly, patients exhibited increased activation of anterior hippocampus during detection of item changes. Whole brain analyses revealed reduced fronto-parietal and striatal activation in patients for spatial but not for item change trials.

Conclusions

Results suggest a gradient of hippocampal dysfunction in which posterior hippocampus – which is necessary for processing fine-grained spatial relationships – is underactive, and anterior hippocampus – which may process context more globally - is overactive.

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Patients with schizophrenia show impaired memory for spatial relationships amongst objects in scenes.

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Patients have less posterior hippocampal activation during spatial memory and more anterior hippocampal activation during item memory.

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This gradient of hippocampal dysfunction in schizophrenia, suggests that it should not be examined as a unitary structure in future studies.

Activation of the central melanocortin system chronically reduces body mass without the necessity of long-term caloric restriction

Melanotan II (MTII) is a potent appetite suppressor that rapidly reduces body mass. Given the rapid loss of anorexic response upon chronic MTII treatment, most investigations have focused on the initial physiological adaptations. However, other evidence supports MTII as a long-term modulator of energy balance that remains to be established. Therefore, we examined the chronic effects of MTII on energy homeostasis. MTII (high or low dose) or artificial cerebrospinal fluid (aCSF) was infused into the lateral ventricle of the brain of 6-month-old F344BN rats (6-7/group) over 40 days. MTII suppressed appetite in a dose-dependent manner (P < 0.05). Although food intake promptly rose back to control level, body mass was persistently reduced in both MTII groups (P < 0.01). At day 40, both MTII groups displayed lower adiposity than the aCSF animals (P < 0.01). These results show that MTII chronically reduces body mass without the requirement of long-term caloric restriction. Our study proposes that food restriction helps initiate mass loss; however, combined with a secondary pharmacological approach preserving a negative energy balance state over time may help combat obesity.

BOLD fMRI in awake prairie voles: A platform for translational social and affective neuroscience

The advancement of neuroscience depends on continued improvement in methods and models. Here, we present novel techniques for the use of awake functional magnetic resonance imaging (fMRI) in the prairie vole (Microtus ochrogaster) - an important step forward in minimally-invasive measurement of neural activity in a non-traditional animal model. Imaging neural responses in prairie voles, a species studied for its propensity to form strong and selective social bonds, is expected to greatly advance our mechanistic understanding of complex social and affective processes. The use of ultra-high-field fMRI allows for recording changes in region-specific activity throughout the entire brain simultaneously and with high temporal and spatial resolutions. By imaging neural responses in awake animals, with minimal invasiveness, we are able to avoid the confound of anesthesia, broaden the scope of possible stimuli, and potentially make use of repeated scans from the same animals. These methods are made possible by the development of an annotated and segmented 3D vole brain atlas and software for image analysis. The use of these methods in the prairie vole provides an opportunity to broaden neuroscientific investigation of behavior via a comparative approach, which highlights the ethological relevance of pro-social behaviors shared between voles and humans, such as communal breeding, selective social bonds, social buffering of stress, and caregiving behaviors. Results using these methods show that fMRI in the prairie vole is capable of yielding robust blood oxygen level dependent (BOLD) signal changes in response to hypercapnic challenge (inhaled 5% CO2), region-specific physical challenge (unilateral whisker stimulation), and presentation of a set of novel odors. Complementary analyses of repeated restraint sessions in the imaging hardware suggest that voles do not require acclimation to this procedure. Taken together, awake vole fMRI represents a new arena of neurobiological study outside the realm of traditional rodent models.

High dietary fructose does not exacerbate the detrimental consequences of high fat diet on basilar artery function

The objective of the study was to determine the effects of a high fat (HF) diet alone or with high fructose (HF/F) on functional and structural changes in the basilar arteries and cardiovascular health parameters in rats. Male Sprague Dawley rats were fed either a HF (30%) or HF/F (30/40%) diet for 12 weeks. The basilar artery was cannulated in a pressurized system (90 cm H2O) and vascular responses to KCl (30 - 120 mM), endothelin (10(-11) - 10(-7) M), acetylcholine (ACh) (10(-10) - 10(-4) M), diethylamine (DEA)-NONO-ate (10(-10) - 10(-4) M), and papaverine (10(-10) - 10(-4) M) were evaluated. Rats were also monitored for food intake, body weight, blood lipids, blood pressure, and heart rate. At death, asymmetrical dimethyl arginine level (ADMA) and leptin were assayed in serum. Although there was no significant difference in weight gain and food intake, HF and HF/F diets increased body fat composition and decreased the lean mass. HF/F diet accelerated the development of dyslipidemia. Although resting blood pressure remained unchanged, stress caused a significant elevation in blood pressure and a modest increase in heart rate in HF fed rats. Both HF and HF/F diet resulted in decreased response to endothelium-dependent and -independent relaxation, whereas increased basilar artery wall thickness was observed only in HF group. Serum leptin levels positively correlated with wall thickness. Moreover serum ADMA was increased and eNOS immunofluorescence was significantly decreased with both diets. These data suggest that the presence of high fructose in a HF diet does not exacerbate the detrimental consequences of a HF diet on basilar artery function.

Childbirth and symptoms of postpartum depression and anxiety: a prospective birth cohort study

We investigated associations between aspects of childbirth and elevated postpartum symptoms of depression and anxiety. We employed secondary analysis of perinatal data (N = 4657-4946) from the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort. Multivariable logistic regression models (adjusted for covariates) examined predictors of elevated symptoms of postpartum depression and anxiety. Predictors included the following: type of delivery (normal physiological vs. interventive non-physiological), immediate postpartum complications, and maternal perception of the recent birth experience. The Edinburgh Postnatal Depression Scale assessed elevated symptoms of depression (score ≥ 13), and the Crown-Crisp Experiential Index assessed elevated symptoms of anxiety (score ≥ 9) at 2 and 8 months after delivery. A more negative perception of the recent birth experience was associated with elevated symptoms of anxiety at 2 months [odds ratio (OR) 1.52, 95 % confidence interval (CI) 1.25-1.85] and 8 months (OR 1.30, 95 % CI 1.06-1.60) postpartum but was not associated with elevated symptoms of depression at either time point. Type of delivery (physiological vs. non-physiological) and immediate postpartum complications were not associated with elevated symptoms of depression or anxiety. Our findings suggest that improving women's childbirth experience may decrease the likelihood of postpartum anxiety, but not postpartum depression.

Interaction between oxytocin receptor DNA methylation and genotype is associated with risk of postpartum depression in women without depression in pregnancy

Postpartum depression (PPD) affects up to 19% of women, negatively impacting maternal and infant health. Reductions in plasma oxytocin levels have been associated with PPD and heritability studies have established a genetic contribution. Epigenetic regulation of the oxytocin receptor gene (OXTR) has been demonstrated and we hypothesized that individual epigenetic variability at OXTR may impact the development of PPD and that such variability may be central to predicting risk. This case-control study is nested within the Avon Longitudinal Study of Parents and Children and included 269 cases with PPD and 276 controls matched on age group, parity, and presence or absence of depressive symptoms in pregnancy as assessed by the Edinburgh Postnatal Depression Scale. OXTR DNA methylation (CpG site -934) and genotype (rs53576 and rs2254298) were assayed from DNA extracted from blood collected during pregnancy. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association of elevated symptoms of PPD with genotype, methylation, and their interaction adjusted for psychosocial factors (n = 500). There was evidence of an interaction between rs53576 and methylation in the OXTR gene amongst women who did not have depression prenatally but developed PPD (p interaction = 0.026, adjusted for covariates, n = 257). Those women with GG genotype showed 2.63 greater odds of PPD for every 10% increase in methylation level (95% CI: 1.37, 5.03), whereas methylation was unrelated to PPD amongst "A" carriers (OR = 1.00, 95% CI: 0.58, 1.73). There was no such interaction among women with PPD and prenatal depression. These data indicate that epigenetic variation that decreases expression of OXTR in a susceptible genotype may play a contributory role in the etiology of PPD.

Deficits in anticipatory but not consummatory pleasure in people with recent-onset schizophrenia spectrum disorders

The majority of studies examining self-reported anticipatory and consummatory pleasure in schizophrenia, as measured on the Temporal Experience of Pleasure Scale (TEPS), have been conducted on chronically ill people with the disorder. In this study, people with a recent-onset schizophrenia spectrum diagnosis (first psychotic episode within one year of study participation) (n=88) and people without a schizophrenia spectrum diagnosis (n=66) were administered the TEPS. People with a schizophrenia spectrum diagnosis reported significantly lower scores of anticipatory, but not consummatory, pleasure on the TEPS compared to the control group. TEPS anticipatory pleasure scores were also significantly, negatively correlated with negative symptoms, but neither TEPS anticipatory nor consummatory pleasure scores were significantly correlated with functioning measures. Our results replicate previous findings with chronically ill people with schizophrenia on the TEPS.

Is oxytocin a maternal-foetal signalling molecule at birth? Implications for development

The neuropeptide oxytocin was first noted for its capacity to promote uterine contractions and facilitate delivery in mammals. The study of oxytocin has grown to include awareness that this peptide is a neuromodulator with broad effects throughout the body. Accumulating evidence suggests that oxytocin is a powerful signal to the foetus, helping to prepare the offspring for the extrauterine environment. Concurrently, the use of exogenous oxytocin or other drugs to manipulate labour has become common practice. The use of oxytocin to expedite labour and minimise blood loss improves both infant and maternal survival under some conditions. However, further investigations are needed to assess the developmental consequences of changes in oxytocin, such as those associated with pre-eclampsia or obstetric manipulations associated with birth. This review focuses on the role of endogenous and exogenous oxytocin as a neurochemical signal to the foetal nervous system. We also examine the possible developmental consequences, including those associated with autism spectrum disorder, that arise from exogenous oxytocin supplementation during labour.

Oxytocin and vasopressin systems in genetic syndromes and neurodevelopmental disorders

Oxytocin (OT) and arginine vasopressin (AVP) are two small, related neuropeptide hormones found in many mammalian species, including humans. Dysregulation of these neuropeptides have been associated with changes in behavior, especially social interactions. We review how the OT and AVP systems have been investigated in Autism Spectrum Disorder (ASD), Prader-Willi Syndrome (PWS), Williams Syndrome (WS) and Fragile X syndrome (FXS). All of these neurodevelopmental disorders (NDD) are marked by social deficits. While PWS, WS and FXS have identified genetic mutations, ASD stems from multiple genes with complex interactions. Animal models of NDD are invaluable for studying the role and relatedness of OT and AVP in the developing brain. We present data from a FXS mouse model affecting the fragile X mental retardation 1 (Fmr1) gene, resulting in decreased OT and AVP staining cells in some brain regions. Reviewing the research about OT and AVP in these NDD suggests that altered OT pathways may be downstream from different etiological factors and perturbations in development. This has implications for ongoing studies of the therapeutic application of OT in NDD. This article is part of a Special Issue entitled Oxytocin and Social Behav.

Cognition in schizophrenia and schizo-affective disorder: impairments that are more similar than different

BACKGROUND

Cognition is increasingly being recognized as an important aspect of psychotic disorders and a key contributor to functional outcome. In the past, comparative studies have been performed in schizophrenia and schizo-affective disorder with regard to cognitive performance, but the results have been mixed and the cognitive measures used have not always assessed the cognitive deficits found to be specific to psychosis. A set of optimized cognitive paradigms designed by the Cognitive Neuroscience Test Reliability and Clinical Applications for Schizophrenia (CNTRACS) Consortium to assess deficits specific to schizophrenia was used to measure cognition in a large group of individuals with schizophrenia and schizo-affective disorder.

METHOD

A total of 519 participants (188 with schizophrenia, 63 with schizo-affective disorder and 268 controls) were administered three cognitive paradigms assessing the domains of goal maintenance in working memory, relational encoding and retrieval in episodic memory and visual integration.

RESULTS

Across the three domains, the results showed no major quantitative differences between patient groups, with both groups uniformly performing worse than healthy subjects.

CONCLUSIONS

The findings of this study suggests that, with regard to deficits in cognition, considered a major aspect of psychotic disorder, schizophrenia and schizo-affective disorder do not demonstrate major significant distinctions. These results have important implications for our understanding of the nosological structure of major psychopathology, providing evidence consistent with the hypothesis that there is no natural distinction between cognitive functioning in schizophrenia and schizo-affective disorder.

Neuroendocrine and behavioural responses to exposure to an infant in male prairie voles

Paternal behaviour and pair-bond formation are defining characteristics of social monogamy. However, in comparison to pair-bonding, the endocrine factors associated with the male care of young are not well studied. In the present study, plasma concentrations of oxytocin, vasopressin and corticosterone (CORT) were measured in reproductively naïve male prairie voles as a function of exposure to an infant or control manipulations (i.e. handling or exposure to a wooden dowel). Plasma oxytocin concentrations were transiently elevated within 10 min of pup exposure. Although plasma CORT concentration typically increases after handling, after 10 min of pup exposure, the concentration of plasma CORT was not increased, suggesting an attenuation of CORT release by pup exposure. Group differences in the concentrations of plasma hormones were no longer detected at 20 or 60 min after treatment. These patterns of rapid change in the concentrations of plasma oxytocin and CORT were observed in both juvenile and adult males but not detected after control procedures. Plasma vasopressin, assessed only in adult males, did not vary as a function of pup exposure or other manipulations. In the paraventricular nucleus of the hypothalamus, pup exposure also increased activation (as assessed by the measurement of c-Fos) of neurones that stained for either oxytocin or vasopressin, whereas it decreased c-Fos expression in neurones stained for corticotrophin-releasing hormone. In addition, brief pup exposure (20 min) facilitated subsequent partner preference formation when alloparental males and pup attackers were considered as a group. In the context of other studies, these data support the hypothesis that neuroendocrine changes associated with male alloparental behaviour are related to those implicated in pair-bonding.

Divergent effects of two different doses of intranasal oxytocin on facial affect discrimination in schizophrenic patients with and without polydipsia

RATIONALE

Hyponatremia and dexamethasone resistance in polydipsic schizophrenic patients are attributable to changes in hippocampal-modulated antidiuretic and stress hormone activity, respectively. The relationship of the neuroendocrine findings to the psychiatric illness, however, is unknown. An impaired ability to identify facial emotions has been linked to core features of schizophrenia and to diminished levels of the closely related hormone, oxytocin, in the polydipsic subset. Intranasal oxytocin enhances facial affect discrimination in healthy subjects.

OBJECTIVE

The aim of this study is to explore if oxytocin reverses impaired facial affect discrimination in schizophrenic patients with, relative to that in patients without, polydipsia.

METHODS

Intranasal oxytocin (10 or 20 IU) and placebo were administered on three occasions to five polydipsic schizophrenic patients, eight nonpolydipsic patients, and 11 healthy controls. Subsequently, subjects rated the presence and intensity of six facial emotions.

RESULTS

Emotion recognition fell in both patient groups following 10 IU of oxytocin due to an increased propensity to identify all emotions regardless of whether they were displayed. By contrast, emotion recognition improved following 20 IU in polydipsic relative to nonpolydipsic patients due primarily to divergent effects on the bias to identify fear in nonfearful faces.

CONCLUSION

The effects of 20 IU oxytocin support the hypothesis that altered neuroendocrine function in polydipsic patients contributes to their psychiatric illness. Further studies are warranted to confirm these findings and assess if oxytocin treatment improves social functioning in this subset. This is the first psychopharmacologic study to compare different doses of oxytocin in the same subject, thus the significance of the opposing responses is unclear.

Effects of age on thermal sensitivity in the rat

Age-dependent changes in thermal sensitivity were evaluated with reflex- and operant-based assessment strategies in animals ranging in age from 8 to 32 months. The impact of inflammatory injury on thermal sensitivity was also determined in animals of different ages. The results showed that operant measures of escape behavior are needed to demonstrate significant changes in thermal sensitivity across the life span of female Long-Evans rats. Increased escape from both heat (44.5 degrees C) and cold (1.5 degrees C-15 degrees C) was observed for older animals, with a greater relative increase in sensitivity to cold. Physical performance deficits were demonstrated with aging but were not associated with changes in escape responding. Reflex responding to cold stimulation was impaired in older animals but was also influenced by physical disabilities. Reflex responding to heat was not affected by increasing age. Inflammation induced by formalin injections in the dorsal hindpaw increased thermal sensitivity significantly more in older animals than in their younger counterparts.

Oxytocin administration, but not social housing condition, reduces growth rate of human breast cancer xenografts (MCF7) in SCID mice

Abstract #5076

Background: Oxytocin decreases human breast cancer cell proliferation in vitro and oxytocin receptors are reported to be present on at least 80% of human breast tumors. Animal studies show increased oxytocin levels in association with pair bonding, maternal care giving and mating behavior. Our experiment tested two hypotheses: 1) exogenous administration of oxytocin(OT) and 2) sibling-group housing, compared to individual housing, will reduce the growth in human breast cancer cell -MCF7-xenografts in SCID mice. We also hypothesized this effect would be mediated by differences in circulating OT. Materials and Methods: A 2 X 2 design was used to study 48 animals. Half of the animals lived in group(GRP) housing, the others were housed singly(SGL). Half of the animals in each housing group received OT (10-9 M) administered by a continuous release pellet(Innovative Research of America) and the others received a placebo(PBO) pellet. At weaning(4 wks), SCID mice were randomized to individual cages vs. groups of 4 mice per cage. At maturation (vaginal cornification-8 wks), continuous release estrogen pellets were implanted and two days later MCF7 cells(0.1ml/10X106)were implanted in the mammary fat pad. Pellets containing OT or PBO were implanted, subcutaneously, 2 days after the MCF7 cells. Plasma was collected 2 days prior to and 2 days following pellet & cell implantation, 14 days later and at sacrifice (41 – 60 d) for analysis of OT concentration using enzyme immunoassay (Assay Designs, Inc). Tumor volumes were measured every three days. Statistical Analyses: A natural log transformation of the plasma OT levels was used to reduce skewness in the observed values. Tumor volumes were converted to cubed root to linearize and a regression line was fit to generate tumor growth rate(slope). Differences in tumor growth rate by housing condition (GRP/SGL), oxy Rx(Y/N) and OT plasma levels were tested by mixed effects ANOVA. Results: OT plasma levels in animals with OT pellets, as compared to PBO, were significantly different at 2 & 14 days after pellet implantation(p=0.001), but not at baseline or at sacrifice. OT plasma levels were higher in group vs single housing (p=.023). Due to the lack of difference in plasma OT at the time of sacrifice, we limited prediction of tumor growth rate to the first 29 days when OT pellets were secreting OT (extrapolation from levels at 2 & 14 days). Slower tumor growth rate occurred with OT treatment compared to PBO(p=0.031), and with higher OT plasma levels(p=0.032) but not with group vs. single housing.&#x2028; Discussion: Continuous oxytocin administration over 29 days produced increased oxytocin plasma levels and both were associated with reduced MCF7 xenograft growth rate in SCID mice. Our next step will be to test whether breast tumor oxytocin receptor density moderates the association between plasma oxytocin and tumor growth rate.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 5076.

Neuroimaging of cognitive disability in schizophrenia: search for a pathophysiological mechanism

This article reviews how functional neuroimaging research of cognitive dysfunction in schizophrenia has resulted in a progression of influential pathophysiological models of the disorder. The review begins with discussion of the 'hypofrontality' model, moving from resting studies examining anterior to posterior gradients of cerebral blood flow (CBF), to cognitive activation studies employing the Wisconsin Card Sorting Test, and current functional magnetic resonance imaging (fMRI) studies of working memory and cognitive control utilizing parametric task designs and event-related procedures. A similar progression is described for development of the temporal lobe model of schizophrenia, moving from research on the temporal cortex and language processing to the hippocampal formation and long-term memory (LTM). These LTM studies found that hippocampal dysfunction was often accompanied by disrupted prefrontal function, supporting a hybrid model of impaired fronto-temporal connectivity. Developments in image analysis procedures are described that allow assessment of these distributed network models. However, given limitations in temporal and spatial resolution, current methods do not provide 'real-time' imaging of network activity, making arrival at a definitive pathophysiologic mechanism difficult. Dorsolateral prefrontal cortex (DLPFC) dysfunction and disrupted fronto-temporal integration appear to be equally viable current models. The article concludes with a discussion of how fMRI can help facilitate development of novel psychosocial and pharmacological interventions designed to improve cognition and functional outcome in patients with schizophrenia.

Association of the oxytocin receptor gene (OXTR) in Caucasian children and adolescents with autism

The oxytocin receptor gene (OXTR) has been studied in autism because of the role of oxytocin (OT) in social cognition. Linkage has also been demonstrated to the region of OXTR in a large sample. Two single nucleotide polymorphisms (SNPs) and a haplotype constructed from them in OXTR have been associated with autism in the Chinese Han population. We tested whether these associations replicated in a Caucasian sample with strictly defined autistic disorder. We genotyped the two previously associated SNPs (rs2254298, rs53576) in 57 Caucasian autism trios. Probands met clinical, ADI-R, and ADOS criteria for autistic disorder. Significant association was detected at rs2254298 (p=0.03) but not rs53576. For rs2254298, overtransmission of the G allele to probands with autistic disorder was found which contrasts with the overtransmission of A previously reported in the Chinese Han sample. In both samples, G was more frequent than A. However, in our Caucasian autism trios and the CEU Caucasian HapMap samples the frequency of A was less than that reported in the Chinese Han and Chinese in Bejing HapMap samples. The haplotype test of association did not reveal excess transmission from parents to affected offspring. These findings provide support for association of OXTR with autism in a Caucasian population. Overtransmission of different alleles in different populations may be due to a different pattern of linkage disequilibrium between the marker rs2254298 and an as yet undetermined susceptibility variant in OXTR.

Impairments in frontal cortical gamma synchrony and cognitive control in schizophrenia

A critical component of cognitive impairments in schizophrenia can be characterized as a disturbance in cognitive control, or the ability to guide and adjust cognitive processes and behavior flexibly in accordance with one's intentions and goals. Cognitive control impairments in schizophrenia are consistently linked to specific disturbances in prefrontal cortical functioning, but the underlying neurophysiologic mechanisms are not yet well characterized. Synchronous gamma-band oscillations have been associated with a wide range of perceptual and cognitive processes, raising the possibility that they may also help entrain prefrontal cortical circuits in the service of cognitive control processes. In the present study, we measured induced gamma-band activity during a task that reliably engages cognitive control processes in association with prefrontal cortical activations in imaging studies. We found that higher cognitive control demands were associated with increases in induced gamma-band activity in the prefrontal areas of healthy subjects but that control-related modulation of prefrontal gamma-band activity was absent in schizophrenia subjects. Disturbances in gamma-band activity in patients correlated with illness symptoms, and gamma-band activity correlated positively with performance in control subjects but not in schizophrenia patients. Our findings may provide a link between previously reported postmortem abnormalities in thalamofrontocortical circuitry and alterations in prefrontal activity observed in functional neuroimaging studies. They also suggest that deficits in frontal cortical gamma-band synchrony may contribute to the cognitive control impairments in schizophrenia.

Neonatal oxytocin manipulations have long-lasting, sexually dimorphic effects on vasopressin receptors

Developmental exposure to oxytocin (OT) or oxytocin antagonists (OTAs) has been shown to cause long-lasting and often sexually dimorphic effects on social behaviors in prairie voles (Microtus ochrogaster). Because regulation of social behavior in monogamous mammals involves central receptors for OT, arginine vasopressin (AVP), and dopamine, we examined the hypothesis that the long-lasting, developmental effects of exposure to neonatal OT or OTA might reflect changes in the expression of receptors for these peptides. On postnatal day 1, prairie voles were injected intraperitoneally with either OT (1 mg/kg), an OTA (0.1 mg/kg), saline vehicle, or were handled only. At approximately 60 days of age, vasopressin V1a receptors, OT receptors (OTR) and dopamine D2 receptor binding were quantified using receptor autoradiography in brain tissue taken from males and females. Significant treatment effects on V1a binding were found in the bed nucleus of the stria terminalis (BNST), cingulate cortex (CgCtx), mediodorsal thalamus (MdThal), medial preoptic area of the hypothalamus (MPOA), and lateral septum (LS). The CgCtx, MPOA, ventral pallidum, and LS also showed significant sex by treatment interactions on V1a binding. No significant treatment or sex differences were observed for D2 receptor binding. No significant treatment difference was observed for OTR receptor binding, and only a marginal sex difference. Changes in the neuropeptide receptor expression, especially the V1a receptor, may help to explain sexually dimorphic changes in behavior that follow comparable neonatal manipulations.

Error detection, correction, and prevention in the brain: a brief review of data and theories

Errors during speeded response tasks are typically immediately followed by a large component in the event-related potential, the error-related negativity; various lines of research have suggested that this component is primarily generated by the anterior cingulate cortex. This error-related activity has generated a high level of interest and investigation by cognitive neuroscientists because of the importance of online action monitoring for theories of cognitive regulation. A subsequent component, the error positivity, has remained more elusive to date. In this review we will discuss some of the extensive research which has suggested that these components are related to performance monitoring, and, should performance be compromised, dynamically adjusting control processes. Furthermore, evidence from patients with mental illnesses, including schizophrenia and obsessive-compulsive disorder, suggests that such illnesses might be understood as resulting in part from disturbances in this action monitoring function.

Neonatal manipulation of oxytocin affects expression of estrogen receptor alpha

In adult females many of the effects of the neuropeptide oxytocin are steroid, and especially estrogen dependent. Here we demonstrate for the first time that neonatal manipulation of oxytocin can affect the expression of estrogen receptor alpha. On the first day of postnatal life male and female prairie voles (Microtus ochrogaster) were randomly assigned to receive one of four treatments; (a) 50 microl i.p. injection of 3 microg oxytocin (approximately 1 microg/g), (b) 0.3 microg of an oxytocin antagonist (approximately 0.1 microg/g), or (c) isotonic saline. A fourth group was handled, but not injected. On postnatal day 8 or 21, brain tissue was collected, fixed and sectioned. Free-floating sections were stained for estrogen receptor alpha using immunocytochemistry, and estrogen receptor alpha immunoreactive neurons were compared by age, treatment, and sex. To compare the temporal expression of estrogen receptor alpha an additional set of brains was collected from untreated males and females on the day of birth. The effects of oxytocin manipulations were age dependent, sexually dimorphic, and site-specific. While there were no significant treatment effects on postnatal day 8, by postnatal day 21 females that received oxytocin showed a significant increase in the number of cells expressing estrogen receptor alpha-immunoreactivity in the ventromedial nucleus of the hypothalamus. Treatment with oxytocin antagonist resulted in a significant decrease in estrogen receptor alpha-immunoreactivity in the medial preoptic area in postnatal day 21 females. While there were no significant effects in males, males treated with oxytocin antagonist trended toward a reduction in estrogen receptor alpha-immunoreactivity in the medial amygdala. The results indicate that oxytocin can have organizational effects on the expression of estrogen receptor alpha, that these effects are sexually dimorphic, and finally that during the preweaning period the development of estrogen receptor alpha is sexually dimorphic.

Functional neuroimaging indicators of successful executive control in the oldest old

Attentional control, motor planning abilities, and executive cognitive functions (ECF) rapidly decline with age. In particular, older adults experience difficulty in manipulating selected motor responses in the presence of conflicting or distracting information. To examine age-related changes in the neural substrates of the attentional and motor planning components of ECF, we assessed the patterns of brain activation in 8 cognitively normal older adults (mean age 81.5) and 20 young individuals (mean age 23.0) while they responded to low and high loads of attentional demands of the Preparing to Overcome Prepotency (POP) task. In the POP task, the selection of one out of two possible motor responses in the presence of increasing attentional task loads determines the accuracy of the performance. Older individuals were slower than young adults (P < 0.001) but achieved a strikingly high accuracy similar to the young group (P = 0.2), regardless of the task load. Both groups showed a load-related fMRI signal increase in the anterior cingulate cortex (ACC), posterior parietal cortex (PPC: Brodmann areas 7 and 40), and dorsolateral prefrontal cortex (dLPFC: Brodmann areas 9, 45, and 46) bilaterally. Compared to young individuals, older adults had lower activation in dLPFC (Brodmann areas 9, 45, and 46: P = 0.007, P = 0.043, and P = 0.040) and Brodmann area 7, P = 0.002. Activation in Brodmann areas 40 and ACC was similar in the two groups (P > 0.05). Among older adults, the most successful performers were those who responded to increasing task loads with greater activation in PPC (Brodmann area 40), despite lower dLPFC activation. Older adults who are able to perform executive control tasks as well as young adults, also seem to implement speed-accuracy trade-off strategies which may rely on increased parietal activation.

Neonatal manipulation of oxytocin alters oxytocin levels in the pituitary of adult rats

The neuropeptide oxytocin (OT) and its OT antagonists (OTA) in infant rats affect their behavior as adults. In this study we attempted to determine whether treating rats on the day of birth (postnatal day 1) with OT or OTA would affect brain OT levels of these rats as adults. Rat pups were injected with OT (3 microg), OTA (0.3 microg) or saline vehicle ip on postnatal day 1. As 60-day-old adults, treated rats were killed, and the OT content in their medial preoptic areas (MPOAs), medial hypothalami (MH) and pituitaries were assayed. In females, treatment with OTA on postnatal day 1 significantly decreased pituitary OT levels as adults. In males, by contrast, treatment with OTA on postnatal day 1 resulted in increased pituitary OT levels when they become adults compared to male rats treated with OT on postnatal day 1. There were no significant effects of neonatal treatment on OT levels in either the MH or MPOA. Day 1 postnatal treatment with OT or OTA had a long-term sexually dimorphic effect on OT levels in the pituitary.

Morphometric analysis of gray matter volume in demented older adults: exploratory analysis of the cardiovascular health study brain MRI database

We tested the feasibility of a fully automated brain MRI voxel count technique--automated labeling pathway (ALP)--in a sample of 15 demented and 13 cognitively normal women (age 75-85 years) participating to the Cardiovascular Health Study (CHS). We hypothesized that ALP would replicate well-established findings of the anatomical correlates of dementia. In particular, we hypothesized that ALP volumetric measures would: (1) significantly differ between cognitively normal and demented women in those brain areas that are established markers for diagnosis of dementia (temporal and medial temporal lobes, hippocampus, amygdala and parahippocampus) but not in other brain areas (e.g., occipital lobe, visual cortex, motor cortex) and (2) correlate with visual ratings of brain disease which have been previously collected as part of the CHS. ALP required minimal operator intervention (input of brain images and verification of misalignments) and employed computer time of about 1 h per brain. ALP detected significant focal volumetric differences in the limbic system (p values between groups for hippocampus and parahippocampus: 0.002 and 0.005, respectively), temporal lobe (p < 0.0001) and caudate (p = 0.009), but not in other brain areas (e.g. occipital lobe, visual or motor cortex). Furthermore, ALP measures of medial temporal lobe atrophy strongly correlated with CHS visual ratings of ventricular enlargement (r(2) = 0.6, p = 0.002 for medial temporal lobe). In conclusion, ALP-detected focal brain atrophy was strongly associated with dementia. Because of its fully automated design, ALP technique is an ideal candidate to assess whether volumetric measures of specific areas can discriminate dementia better than currently available measures of global brain atrophy in large epidemiological studies.

Mathematical models for pressure controlled ventilation of oleic acid-injured pigs

One-compartment, mathematical models for pressure controlled ventilation, incorporating volume dependent compliances, linear and nonlinear resistances, are constructed and compared with data obtained from healthy and (oleic acid) lung-injured pigs. Experimental data are used to find parameters in the mathematical models and were collected in two forms. Firstly, the P(e)-V curves for healthy and lung injured pigs were constructed; these data are used to compute compliance functions for each animal. Secondly, dynamic data from pressure controlled ventilation for a variety of applied pressures are used to estimate resistance parameters in the models. The models were then compared against the collected dynamic data. The best mathematical models are ones with compliance functions of the form C(V) = a + bV where a and b are constants obtained from the P(e)-V curves and the resistive pressures during inspiration change from a linear relation P(r) = RQ to a nonlinear relation P(r) = RQ(epsilon) where Q is the flow into the one-compartment lung and epsilon is a positive number. The form of the resistance terms in the mathematical models indicate the possible presence of gas-liquid foams in the experimental data.

Comparison of automated culture systems with a CFR/USP-compliant method for sterility testing of cell-therapy products

BACKGROUND

Although widely used, commercially available automated culture methods are not US Food and Drug Administration-approved for sterility testing of cell-therapy products. For cell-therapy products regulated under Section 351 of the Public Health Service Act, sterility testing must be performed by the methods described in 21 CFR 610.12 and USP <71> (CFR/USP method), or by methods demonstrated to be equivalent.

METHODS

Two automated methods, BacT/Alert (BTA; bioMerieux) and Bactec (Becton Dickinson), were compared with the CFR/USP method. Representative mononuclear cell (MNC) products were formulated using six different product media. MNC product aliquots containing 10-50 x 10(6) cells in a 0.5 mL volume were seeded with organisms, and cultured for 14 days in aerobic and anaerobic bottles of each system. Ten different organisms at target concentrations of 10 and 50 colony-forming units (CFU) per bottle were tested.

RESULTS

Positives were detected in a mean (range) of 72% (7-100%) of cultures for CFR/USP, 82% (0-100%) for BTA, and 93% (57-100%) for Bactec. For nine of the 10 organisms tested, overall detection rates for BTA and Bactec were equivalent to or higher than CFR/USP. Of the six product media tested, detection of organisms was impaired only by the medium containing multiple antibiotics: this occurred in all three systems. Both BTA and Bactec had shorter times to detection than the CFR/USP method, with overall means (ranges) of 87 (24-264) h for CFR/USP, 24 (12-54) h for BTA, and 33 (12-80) h for Bactec. Detection occurred consistently within 7 days for both BTA and Bactec, but not for CFR/USP.

DISCUSSION

Both BTA and Bactec are superior to the CFR/USP method for overall detection and time to detection of organisms in MNC products suspended in commonly used media. These data support general use of either BTA or Bactec for sterility testing of a variety of cell-therapy products, and suggest that a 7-day culture period is sufficient to detect clinically relevant organisms. These results confirm the need for bacteriostasis and fungistasis testing of antibiotic-containing products, even when antibiotic-binding substances are used.

Neonatal manipulations of oxytocin alter expression of oxytocin and vasopressin immunoreactive cells in the paraventricular nucleus of the hypothalamus in a gender-specific manner

Early postnatal manipulations of oxytocin have long-term behavioral and physiological consequences; the present study examined the hypothesis that oxytocin or its absence influences the subsequent expression of either oxytocin or arginine vasopressin in the CNS. On postnatal day 1 female and male prairie voles (Microtus ochrogaster) received a single i.p. injection of oxytocin (3 microg), oxytocin antagonist (0.3 microg), or 50 microl of isotonic saline or were only handled. On postnatal days 1, 8 and 21, brains were fixed, sectioned and stained for oxytocin or vasopressin immunoreactivity and analyzed as a function of age, treatment and sex. Both oxytocin and vasopressin immunoreactivity were observed on day 1 in the supraoptic and paraventricular nuclei (PVN) of the hypothalamus. Numbers of oxytocin and vasopressin neurons increased with age in both nuclei. Females treated on postnatal day 1 with oxytocin or oxytocin antagonist displayed a significant increase in oxytocin immunoreactivity on day 21 in the PVN. In contrast, males treated with antagonist tended to have decreased vasopressin immunoreactivity in the same region. These results revealed that the effects of neonatal manipulation of oxytocin are age-dependent, site-specific and sexually dimorphic. The long-lasting effects of neonatal exposure to exogenous oxytocin and oxytocin antagonist indicate a role for oxytocin in the development of the CNS during the neonatal period, affecting the development of the oxytocinergic system in females and the vasopressinergic system in males. The developmental effects observed suggest one possible mechanism by which neonatal exposure to oxytocin or neonatal inhibition of endogenous oxytocin produces long-lasting behavioral and physiological alterations and could play a role in the development of male- and female-typical behavior.

Growth hormone treatment attenuates age-related changes in hippocampal short-term plasticity and spatial learning

Downregulation of the growth hormone/insulin-like growth factor-1 (IGF-1)axis is one of the most robust biomarkers of mammalian aging. Reports have suggested that age-related changes in secretion of growth hormone and IGF-1 contribute to the development of some peripheral characteristics of the aged phenotype including decreased bone density and lean body mass. Recent work has focused on the identification of a role for age-related reductions in growth hormone and IGF-1 in the development of cognitive impairments associated with aging. In the current study, we report that aged (30 month-old) Brown Norway x Fisher rats demonstrate impairments in spatial learning compared with adult (10 month-old) animals, and that 4-month treatment with growth hormone (300 microg twice daily) attenuates age-related learning impairments. After 6 months of treatment, we employed an extracellular paired-pulse protocol to investigate age-related changes in hippocampal short-term plasticity, and found that aged rats exhibit significantly increased paired-pulse ratios (PPRs) at an interpulse interval of 50 ms compared with adult rats. Long-term growth hormone administration restored PPRs in aged animals to values comparable to those observed in adult controls. Since the age-related changes observed in PPR may result from decreases in hippocampal inhibitory tone mediated by GABA(A) receptors, we assessed GABA(A) receptor subunit expression by immunoblot analysis. Data revealed significant age-related decreases in GABA(A) receptor alpha-1 subunit expression which were attenuated by growth hormone treatment. However, hippocampal levels of the gamma2 subunit, glutamic acid decarboxylase (GAD)(65), and GAD(67) protein concentrations were not significantly affected by age or growth hormone treatment. In conclusion, we suggest that age-related decreases in growth hormone and IGF-1 contribute to cognitive decline, in part, via alterations in hippocampal short-term plasticity. Changes in plasticity may reflect a shift in the balance of hippocampal inhibitory and excitatory function.

Catastrophic failures of freezing bags for cellular therapy products: description, cause, and consequences

BACKGROUND

Container integrity is critical for maintaining sterility of cryopreserved cellular therapy products. We investigated a series of catastrophic bag failures, first noticed in early 2001.

METHODS

Process records were reviewed for all PBPC and lymphocyte products cryopreserved in bags from January 2000 through April 2002. Patient charts were also reviewed.

RESULTS

One thousand two hundred and four bags were removed from storage for infusion to 261 patients. All products had been cryopreserved in Cryocyte poly(ethylene co-vinyl acetate) (EVA) bags in either 10% DMSO or 5% DMSO and 6% pentastarch. Product volumes were 25-75 mL, and bags were stored with overwrap bags in a liquid nitrogen tank. From January 2000 to April 2001, failure occurred in 10 of 599 (1.7%) bags. From May 2001 to April 2002, 58 of 605 (9.6%) bags failed, typically with extensive fractures that were visible before thaw. Of the 58 that failed, 24 were salvaged by aseptic methods and infused to patients under antibiotic coverage; 10 of those 24 (42%) had positive bacterial cultures. Bag failures were not related to product type, cryoprotectant solution, liquid versus vapor storage, or freezer location. Failures were linked to use of four Cryocyte bag lots manufactured in 2000 and 2001. After replacing these lots with a 1999 Cryocyte lot and with KryoSafe polyfluoroethylene polyfluoropropylene (FEP) bags, no more failures occurred in 75 and 102 bags, respectively, thawed through April 2002.

DISCUSSION

High rates of bag failure were associated with four Cryocyte bag lots. No serious adverse patient effects occurred, but bag failures led to microbial contamination, increased product preparation time, increased antibiotic use, and increased resource expenditure to replace products.

Optimized clinical-scale culture conditions for ex vivo selective depletion of host-reactive donor lymphocytes: a strategy for GvHD prophylaxis in allogeneic PBSC transplantation

BACKGROUND

Ex vivo selective depletion (SD) is a strategy to prevent GvHD, in which host-reactive donor lymphocytes are selectively eliminated from a PBSC allograft while conserving useful donor immune function. Prior to testing this strategy in patients, our goal was to develop a clinical-scale SD process, which involves co-culture of donor lymphocytes and irradiated recipient cells, followed by the addition of an immunotoxin (IT) directed against the alpha-chain of the IL-2 receptor (CD25), expressed on activated donor T cells.

METHODS

Stimulator cells were generated from immunomagnetically selected and expanded recipient T lymphocytes. Donor PBMCs from G-CSF-mobilized peripheral blood were co-cultured for 72 h with irradiated stimulator cells. Alloreactive T cells were targeted for elimination by the addition of the anti-CD25 IT, RFT5-SMPT-dgA, and the IT enhancer, NH(4)Cl.

RESULTS

Stimulator-cell selection/expansion yielded > 2 x 10(10) highly enriched CD3(+) cells (98.9 +/- 2.2%). After SD, cell recovery was 68.5 +/- 23.3% and viability was 84.6 +/- 6.4%. This permitted a potential T-cell dose >/= 1 x 10(8) CD3(+) cells kg(-1) to transplant recipients. Although SD donor lymphocytes retained little proliferative capacity against the original stimulator cells (2.6 +/- 0.6%), responses were conserved against third party cells (107.6 +/- 18.6%), the bacterial superantigen staphylococcus enterotoxin B (108.2 +/- 4.2%), and CMV Ag (72.1 +/- 3.8%).

DISCUSSION

We have demonstrated that ex vivo SD is feasible in clinical-scale culture conditions. The ability of this strategy to prevent GvHD is the subject of an ongoing clinical trial, in which the SD lymphocyte product is transplanted in conjunction with a T cell-depleted PBSC allograft.

Development of a clinical-scale method for generation of dendritic cells from PBMC for use in cancer immunotherapy

BACKGROUND

There is growing interest in the use of dendritic cells (DCs) for treatment of malignancy and infectious disease. Our goal was to develop a clinical scale method to prepare autologous DCs for cancer clinical trials.

METHODS

PBMC were collected from normal donors or cancer patients by automated leukapheresis, purified by counterflow centrifugal elutriation and placed into culture in polystyrene flasks at 1 x 10(6) cells/mL for 5-7 days at 37 degrees C, with 5% CO(2), with IL-4 and GM-CSF. Conditions investigated included media formulation, supplementation with heat in activated allogeneic AB serum or autologous plasma and time to harvest (Day 5 or Day 7). DCs were evaluated for morphology, quantitative yield, viability, phenotype and function, including mixed leukocyte response and recall response to tetanus toxoid and influenza virus.

RESULTS

DCs with a typical immature phenotype (CD14-negative, CD1a-positive, mannose receptor-positive, CD80-positive, CD83-negative) were generated most consistently in RPMI 1640 supplemented with 10% allogeneic AB serum or 10% autologous plasma. Cell yield was higher at Day 5 than Day 7, without detectable differences in phenotype or function. In pediatric sarcoma patients, autologous DCs had enhanced function compared with monocytes from which they were generated. In this patient group, starting with 8.0 +/- 3.7 x 10(8) fresh or cryopreserved autologous monocytes, DC yield was 2.1 +/- 1.0 x 10(8) cells, or 29% of the starting monocyte number.

DISCUSSION

In the optimized clinical-scale method, purified peripheral monocytes are cultured for 5 days in flasks at 1 x 10(6) cells/mL in RPMI 1640, 10% allogeneic AB serum or autologous plasma, IL-4 and GM-CSF. This method avoids the use of FBS and results in immature DCs suitable for clinical trials.

Development of a closed-system process for clinical-scale generation of DCs: evaluation of two monocyte-enrichment methods and two culture containers

BACKGROUND

Clinical immunotherapy trials using DCs depend on large-scale methods for DC generation that fulfil current good manufacturing practice requirements. Our goal was to develop data on two variables, monocyte-enrichment method and culture container, which could be used to design a closed-system process for ex vivo generation of immature DCs.

METHODS

Mononuclear cells were collected by leukapheresis and enriched for monocytes by either counterflow centrifugal elutriation, or immunomagnetic selection using Isolex, an automated closed-system device. Monocytes were cultured for 7 days in serum-free medium with GM-CSF and IL-4, using either plastic flasks or gas-permeable Stericell bags. Monocytes and cultured DCs were evaluated for yield, flow cytometric phenotype, and in vitro function in MLR, and autologous recall responses to tetanus toxoid and influenza virus.

RESULTS

Enriched monocyte products from elutriation and immunomagnetic selection were equivalent in yield and purity, and were capable of generating immature DCs in either flasks or bags. DCs from all four culture conditions were equivalent in yield, phenotype, and in vitro function. Mean DC yield was 67-80% per seeding monocyte, and 11-13% per starting mononuclear cell (MNC). A leukapheresis product containing 5 x 10(9) MNCs processed by this method could therefore yield approximately 5 x 10(8) immature DCs.

DISCUSSION

In this manufacturing process, the Isolex system was equivalent to elutriation, and Stericell bags were equivalent to flasks. Together, the Isolex system and Stericell bags can be incorporated into a closed-system process to generate immature DCs.

The relation of White Matter Hyperintensities to implicit learning in healthy older adults

OBJECTIVE

This study examined whether MRI evidence of cerebrovascular disease in the form of white matter hyperintensities (WMH) was associated with decreased implicit sequence learning performance in a high-functioning group of normal elderly volunteers.

METHOD

One hundred and eight community-dwelling elderly individuals received an MRI and performed an implicit sequence learning task, the serial reaction time (SRT) task.

RESULTS

Hyperintensities present in the white matter were associated with a decreased learning effect. This association was found with both deep white matter and periventricular changes. Other factors affecting SRT performance (i.e., baseline reaction time and switch-cost) were not significantly related to the presence of WMH.

CONCLUSIONS

The results indicate that in addition to previously identified generalized cognitive deficits, WMH are also associated with a specific decrease in the implicit learning of sequences.

Context processing in older adults: evidence for a theory relating cognitive control to neurobiology in healthy aging

A theory of cognitive aging is presented in which healthy older adults are hypothesized to suffer from disturbances in the processing of context that impair cognitive control function across multiple domains, including attention, inhibition, and working memory. These cognitive disturbances are postulated to be directly related to age-related decline in the function of the dopamine (DA) system in the prefrontal cortex (PFC). A connectionist computational model is described that implements specific mechanisms for the role of DA and PFC in context processing. The behavioral predictions of the model were tested in a large sample of older (N = 81) and young (N = 175) adults performing variants of a simple cognitive control task that placed differential demands on context processing. Older adults exhibited both performance decrements and, counterintuitively, performance improvements that are in close agreement with model predictions.

Anterior cingulate cortex, conflict monitoring, and levels of processing

It has been hypothesized that the anterior cingulate cortex (ACC) contributes to cognition by detecting conflicts that might occur during information processing, to signal the need to engage top-down attentional processes. The present study was designed to investigate which levels of processing are being monitored by the ACC for the presence of conflict. Event-related fMRI was used to measure the response of the ACC during an interference task in which distracting information could be congruent, conflicting at the level of stimulus identification, or conflicting at the response level. Although both types of conflict caused reaction time interference, the fMRI data showed that the ACC is responsive only to response conflict, even when controlling for reaction times. These results suggest a highly specific contribution of the ACC to executive functions, through the detection of conflicts occurring at later or response-related levels of processing.

Neuroendocrine and emotional changes in the post-partum period

As well as having widespread effects on many aspects of mammalian physiology, the hormones of both the reproductive and stress axes can directly and indirectly influence behavior. Here we review possible mechanisms through which centrally active hormones of the female reproductive system and the hypothalamo-pituitary-adrenal stress axis may interact to influence behavior and mood states during the post-partum period. We will focus primarily on the behavioral effects of selected neuropeptide hormones, in particular oxytocin, vasopressin and corticotrophin-releasing hormone. The literature documenting central behavioral effects of these neuropeptides arises almost exclusively from research in experimental animals. In particular, it has been reported that during lactation in rats there are high blood and brain levels of oxytocin. At the same time there is a reduction in corticotrophin-releasing hormone in the brain and in its secretion in response to stress. These changes may contribute to optimal maternal care of the offspring. Correlational studies of peptides and behavior in the post-partum period also support the hypothesis that neuropeptides may influence human physiology and behavior. Studies of post-partum women reveal powerful regulatory effects of lactation on the reactivity of the hypothalamo-pituitary-adrenal axis and of autonomic and immune systems, especially in the face of challenge. The integrative function of neural systems that influence both reproduction and the hypothalamo-pituitary-adrenal axis suggests one central mechanism for mediating the effects of environmental challenges.

Transplant dose of CD34(+) and CD3(+) cells predicts outcome in patients with haematological malignancies undergoing T cell-depleted peripheral blood stem cell transplants with delayed donor lymphocyte add-back

We sought to optimize and standardize stem cell and lymphocyte doses of T cell-depleted peripheral blood stem cell transplants (T-PBSCT), using delayed add-back of donor T cells (DLI) to prevent relapse and enhance donor immune recovery. Fifty-one patients with haematological malignancies received a T-PBSCT from an HLA-identical sibling, followed by DLI of 1 x 10(7) and 5 x 10(7) CD3(+) cells/kg on d +45 and +100 respectively. Twenty-four patients were designated as standard risk and twenty-seven patients with more advanced leukaemia were designated as high risk. Median recipient age was 38 years (range 10-56). Median (range) of CD34(+) and CD3(+) cell transplant doses were 4.6 (2.3-10.9) x 10(6)/kg and 0.83 (0.38-2) x 10(5)/kg respectively. The cumulative probability of acute GVHD was 39%. No patient died from GVHD or its consequences. The probability of developing chronic GVHD was 54% (18% extensive). The probability of relapse was 12% for the standard-risk patients and 66% for high-risk patients. In multivariate analysis, the risk factors for lower disease-free survival and overall survival were high-risk disease, CD34(+) dose < 4.6 x 10(6)/kg and CD3(+) dose < 0.83 x 10(5)/kg. Predictive factors for chronic GVHD were a T-cell dose at transplant > 0.83 x 10(5) CD3(+) cells/kg. These results further define the impact of CD34 and CD3 cell dose on transplant outcome and show that careful dosing of stem cells and lymphocytes may permit the control and optimization of transplant outcome.

Responses to laboratory psychosocial stress in postpartum women

OBJECTIVE

Lactation has been associated with attenuated hormonal responses to exercise stress in humans. This study was designed to determine the effect of lactation on hypothalamic-pituitary-adrenal axis, autonomic nervous system, and anxiety responses to psychological stress.

METHOD

The Trier Social Stress Test was administered to 24 lactating women, 13 postpartum nonlactating women, and 14 healthy control women in the early follicular phase of the menstrual cycle. Lactating women were stressed at least 40 minutes after last feeding their infant.

RESULTS

ACTH, cortisol, heart rate, diastolic blood pressure, systolic blood pressure, and subjective anxiety ratings were all significantly increased in response to the psychological stress (all p <.0001). There were no differences among the three groups in any of these responses to the stress. However, postpartum nonlactating women did have a persistently higher systolic blood pressure and lower cardiac vagal tone than the lactating women and control subjects. In addition, the typical negative correlation between cardiac vagal tone and heart rate was consistently higher in lactating women than nonlactating postpartum women and controls, which suggests stronger vagal control of heart rate in lactating women. In addition, there was no change in oxytocin or allopregnanolone in response to the stress, and baseline oxytocin and allopregnanolone levels did not differ among the three groups.

CONCLUSIONS

These results indicate that physiological and subjective responses to social stress are not attenuated in lactating women tested at least one hour after feeding their infant. However, enhanced vagal control of cardiac reactivity was observed in lactating women. In addition, postpartum women who did not lactate showed evidence of increased sympathetic and decreased parasympathetic nervous system tone.

Anterior cingulate cortex activity and impaired self-monitoring of performance in patients with schizophrenia: an event-related fMRI study

OBJECTIVE

The authors examined brain activity associated with the internal monitoring of performance to test the hypothesis that error-related activity in the anterior cingulate cortex is impaired in patients with schizophrenia.

METHOD

Seventeen patients with schizophrenia and 16 healthy comparison subjects underwent event-related functional magnetic resonance imaging during a continuous performance task; stimulus degradation was used to increase error rates.

RESULTS

Comparison subjects, but not schizophrenic patients, showed error-related activity in the anterior cingulate cortex, and this difference in brain activity was significantly different across the two groups. Patients also showed less slowing of reaction time after error commission.

CONCLUSIONS

Lower error-related activity in the anterior cingulate cortex and less performance adjustment after error commission are consistent with the hypothesis that disturbances in anterior cingulate cortex function are related to a specific alteration in an evaluative component of executive functioning-the internal monitoring of performance.