No evidence for G-protein-coupled epsilon receptor in the brain of triple opioid receptor knockout mouse

Pharmacological approaches have defined the epsilon receptor as a beta-endorphin-preferring opioid receptor, described in rat vas deferens and in brain of several species. Only three opioid receptors-mu, delta and kappa-have been cloned and the existence of this additional subtype as a distinct protein remains controversial. Recently, the mouse brain epsilon receptor was detected in a G protein activation assay, as mediating residual beta-endorphin activity following pharmacological blockade of mu, delta and kappa receptors. To clarify whether this site is independent from mu, delta and kappa receptors, we performed beta-endorphin-induced [(35)S]GTPgammaS binding using mice lacking these three receptors (triple knockout mice). We tested both pons-medulla and whole brain preparations. beta-Endorphin strongly stimulated [(35)S]GTPgammaS binding in wild-type membranes but had no detectable effect in membranes from triple knockout mice. We conclude that the brain epsilon site involves mu, delta and/or kappa receptors, possibly coupled to nonclassical G proteins.     

APOE genotype-specific differences in human and mouse macrophage nitric oxide production

Individuals expressing an APOE4 genotype demonstrate increased Alzheimer's disease (AD) neuropathology and a decreased onset age. The APOE4 gene may act by modulating the CNS immune response. Using human monocyte-derived macrophages (MDM), we show a significantly greater increase in NO production during immune activation in MDM from APOE4 AD patients compared to normal, age-matched individuals or to AD patients with an APOE 3/3 genotype. Microglia and peritoneal macrophages from APOE4 targeted replacement mice demonstrate a similar increase in NO compared to the APOE3 targeted replacement mice. The enhanced macrophage responsiveness and the increased production of NO in APOE4 AD patients may predispose the CNS to an increased potential for nitration and nitrosation, consistent with the redox imbalance and neuroinflammatory state seen in AD.     

Cognition in childhood anxiety: conceptual,methodological, and developmental issues

Anxiety disorders are one of the most common psychiatric disorders in the general child population and can have significant impact on immediate and long-term functioning. Despite the common use of cognitive-behavioral interventions that target specific, negative thoughts in anxious children, it is unclear that the extant literature clearly documents cognitive aberrations among these children. In this review, conceptual and methodological issues related to the assessment of cognition in anxious children are highlighted and empirical data addressing these areas are evaluated. Furthermore, data addressing cognitive change as a function of treatment outcome is examined, and the impact of cognitive development as a moderating variable is discussed. Finally, areas for future research are presented.     

Dealing with colon cancer: one woman's emotional journey

Although death is inevitable, it continues to remain a taboo issue for society. A failure to discuss the unavoidable may represent a safeguard to avoid dealing with mortality and related fears. Many patients who are terminally ill spend their days feeling alone, misunderstood, and afraid. Kubler-Ross attempted to strip death of its negative connotations and to provide a venue for the terminally ill to have a voice. Using information from more than 200 clinical interviews, Kubler-Ross revealed a trend in emotions over time in most, but not all, of her patients, which enabled her to formulate a model of coping with death that included 5 interdependent emotional stages: denial, anger, bargaining, depression, and acceptance. This model has become the most widely accepted and popularized model on death and dying, often cited as the Five Stages of Grief." However, given the lack of research concerning Kubler-Ross's model, completing work in this area seems warranted. The purpose of this case study was to examine one individual's emotional journey after being diagnosed with terminal colon cancer. More specifically, the goals were twofold: (1) to provide the participant with a voice and to allow her story to be told by examining the major external events (ie,surgery, chemotherapy) occurring since the diagnosis that affected her emotional and physical well-being and (2) to determine whether the participant's emotional journey paralleled Kubler-Ross's model, to what extent, and whether new emotions or stages occurred. The participant, a 50-year-old female, was diagnosed with stage 4 Duke Stage D colon cancer. Qualitative information was collected in face-to-face interviews, newspaper articles about the participant, and e-mail correspondence (as form letters to a group of friends and supporters) and subsequently analyzed for trends. The overall results revealed clear existence of the 5 stages of grief as outlined in the Kubler-Ross model. Analyses also revealed that the stages often overlapped or occurred simultaneously. Additionally, the participant regressed to earlier stages when subjected to negative external factors. Four other highly salient emotions were also prevalent throughout the participant's experience with colon cancer, namely joy, fear, hope, and numbness. The findings from this case study help to validate Kubler-Ross's stages. Further, the importance of the voice of the participant cannot be overemphasized. This case study clearly depicts the unique thoughts and emotions during one woman's struggle with colon cancer, sentiments that are often overlooked in quantitative analysis.     

Isolation of Ixodes ricinus salivary gland mRNA encoding factors induced during blood feeding

In tick salivary glands, genes induced during blood feeding result in the expression of new proteins secreted into tick saliva. These proteins are potentially involved in modulation of vertebrate host immune and hemostatic responses. In this study, subtractive and full-length cDNA libraries were constructed by use of mRNA extracted from salivary glands of unfed and 5-day engorged Ixodes ricinus. Sequences from these 2 libraries were compared with European Molecular Biology Laboratory (EMBL)/GenBank databases, which led to their classification into 2 major groups. The first group comprises cDNAs that failed to match or showed low homology to genes of known function. The second group includes sequences that showed high homology to genes of known function--for example, anticoagulants, inhibitors of platelet aggregation, and immunomodulatory proteins. Analyses of corresponding proteins suggest that they may be secreted by salivary gland cells. To study the properties of the recombinant proteins, selected cDNAs were expressed in mammalian or bacterial systems.     

Multifocal visual evoked potential responses in glaucoma patients with unilateral hemifield defects

PURPOSE: To determine whether the multifocal visual evoked potential (mfVEP) technique can detect damage to the visual system in the unaffected hemifields of patients with glaucoma and unilateral hemifield defects. DESIGN: Experimental study. METHODS: Monocular mfVEPs and achromatic automated perimetry (AAP) were obtained in both eyes of 16 patients with open-angle glaucoma and unilateral hemifield defects. The mfVEPs were obtained using a pattern-reversal dartboard array with 60 sectors; the entire display was 44.5 degrees in diameter. For each pair of mfVEP responses an interocular ratio of root-mean-square amplitude was calculated. These values were compared with the mean values obtained from 30 control subjects. Probability plots for MfVEP were derived. A cluster analysis was used to determine whether an mfVEP hemifield was normal or abnormal. RESULTS: Three of 60 (5.0%) mfVEP hemifields from control subjects had significant mfVEP deficits based upon a cluster of abnormal points. Significant mfVEP deficits were detected in the affected AAP hemifield in 15 of 16 (93.8%) glaucoma patients and in 6 of 16 patients in hemifields with apparently normal AAP. The percentage of hemifields with abnormal mfVEPs, but normal AAP, was significantly higher for the glaucoma patients than for the controls (37.5% vs 5.0%, P <.001, chi square).In glaucomatous eyes with achromatic visual fields defects limited to one hemifield, the mfVEP technique can detect evidence of glaucomatous damage in the unaffected hemifield.     

Repeat reliability of the multifocal visual evoked potential in normal and glaucomatous eyes

PURPOSE: To investigate the repeat reliability of the multifocal visual evoked potential (mfVEP). PATIENTS AND METHODS: Fifteen subjects with no known abnormalities of the visual system and 10 patients with glaucoma participated in the study. Monocular mfVEPs were recorded on two separate days, using a 60-sector, pattern-reversal dart board array. Within a single session, two 7-minute. recordings were obtained for each eye. The amplitude of each mfVEP response was obtained using a root mean square measure (RMS). An mfVEP ratio [10*log (RMS day 1 / RMS day 2)] provided a measure of the reproducibility of an individual response. The same calculations were performed for Run 1 compared with Run 2 within a day and Run 1 (Run 2) compared with Run 1 (Run 2) across days. RESULTS: For all 1800 mfVEP responses (60 sectors x 15 subjects x 2 eyes), the correlation between the amplitude on day 2 and the amplitude on day 1 was good (r = 0.85). The mean standard deviation (SD) of the 60 mfVEP ratios for the individual subjects was 1.63 dB for the 14-minute records (the combination of the two 7-minute recordings). On average for the 7-minute records, the mean SD across days was 1.77 dB while the mean SD within a day was 1.53 dB. The correlation within a day (r = 0.87) also was slightly larger than across days (r = 0.80). The mean SD decreased as the RMS amplitude increased. The patients' mean SD was 1.75 dB with r equal to 0.82. CONCLUSIONS: The repeat reliability of the mfVEP was good (approximately 1.6dB); in fact, it was better than that typically obtained with static automated perimetry (approximately 2.7dB). Repeat testing on separate days added surprisingly little to the variability seen with repeat testing within the same session.