Early postnatal GABAA receptor modulation reverses deficits in neuronal maturation in a conditional neurodevelopmental mouse model of DISC1.

Exploring drug targets based on disease-associated molecular mechanisms during development is crucial for the generation of novel prevention and treatment strategies for neurodevelopmental psychiatric conditions. We report that prefrontal cortex (PFC)-specific postnatal knockdown of DISC1 via in utero electroporation combined with an inducible knockdown expression system drives deficits in synaptic GABAA function and dendritic development in pyramidal neurons, as well as abnormalities in sensorimotor gating, albeit without profound memory deficits. We show for the first time that DISC1 is specifically involved in regulating cell surface expression of α2 subunit-containing GABAA receptors in immature developing neurons, but not after full maturation. Notably, pharmacological intervention with α2/3 subtype-selective GABAA receptor positive allosteric modulators during the early postnatal period ameliorates dendritic deficits and behavioral abnormalities induced by knockdown of DISC1. These findings highlight a critical role of DISC1-mediated disruption of postnatal GABA signaling in aberrant PFC maturation and function.

Risk factors for Nipah virus encephalitis in Bangladesh.

Nipah virus (NiV) is a paramyxovirus that causes severe encephalitis in humans. During January 2004, twelve patients with NiV encephalitis (NiVE) were identified in west-central Bangladesh. A case-control study was conducted to identify factors associated with NiV infection. NiVE patients from the outbreak were enrolled in a matched case-control study. Exact odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by using a matched analysis. Climbing trees (83% of cases vs. 51% of controls, OR 8.2, 95% CI 1.25-infinity) and contact with another NiVE patient (67% of cases vs. 9% of controls, OR 21.4, 95% CI 2.78-966.1) were associated with infection. We did not identify an increased risk for NiV infection among persons who had contact with a potential intermediate host. Although we cannot rule out person-to-person transmission, case-patients were likely infected from contact with fruit bats or their secretions.

Cloning and characterization of the novel gene for mast cell carboxypeptidase A.

No gene for a hematopoietic cell carboxypeptidase has previously been characterized. Mast cell carboxypeptidase A (MC-CPA) is a prominent secretory granule marker of mast cell differentiation and phenotype. The 32-kb human MC-CPA gene was isolated, localized to chromosome 3, and found to contain 11 exons. No significant homology was found between the 5' flanking region of the MC-CPA gene and those of three rat pancreatic carboxypeptidase genes (carboxypeptidase A1 and A2, and carboxypeptidase B [CPB]). In contrast, the intron/exon organization of the MC-CPA gene was conserved, most closely resembling the CPB gene. MC-CPA is unique among carboxypeptidases in having a CPA-like substrate-binding pocket and enzymatic activity despite overall protein and gene structures more similar to CPB. Evolutionary tree analysis of the carboxypeptidase gene family showed that, before the mammalian species radiation, a common MC-CPA/CPB ancestor diverged by gene duplication from the lineage leading to CPA, and then underwent another gene duplication to form separate but similar gene structures for MC-CPA and CPB. MC-CPA mRNA was prominent in dispersed lung cells enriched for mast cells but was undetectable in other nontransformed populations of several lineages, demonstrating that transcription of MC-CPA, a novel carboxypeptidase gene, provides a specific molecular marker for mast cells among normal hematopoietic cell populations.

Benefits and Challenges of Teaching Nursing Online: Exploring Perspectives of Different Stakeholders.

BACKGROUND: Recruiting and retaining faculty to teach courses is crucial for online nursing programs to succeed. The purpose of this study was to gain a fuller understanding of the benefits and challenges of teaching nursing courses online by exploring the perspectives of faculty, administrators, and instructional designers at three schools of nursing in the southeastern United States. METHOD: This qualitative multiple case study explored perspectives of 21 participants from different stakeholder groups. Researchers used cross-case analysis and determined emerging themes in data collected from interviews, course demonstrations, and course documents. RESULTS: Data analysis revealed themes regarding benefits and challenges for nursing instructors in (a) teaching strategies, (b) instructor availability, (c) training and support, and (d) institutional issues. CONCLUSION: This study found gaps in perspectives between participant groups that indicated a need for institutions to address communication issues, training program objectives, and institutional policies and procedures regarding online course design and delivery to promote faculty success and satisfaction. [J Nurs Educ. 2016;55(8):433-440.].

The risk for early-adulthood anxiety and depressive disorders in adolescents with anxiety and depressive disorders.

BACKGROUND: Various studies find relationships among anxiety and depressive disorders of adolescence and adulthood. This study prospectively examines the magnitude of longitudinal associations between adolescent and adult anxiety or depressive disorders. METHODS: An epidemiologically selected sample of 776 young people living in upstate New York received DSM-based psychiatric assessments in 1983, 1985, and 1992 using structured interviews. The magnitude of the association between adolescent and adult anxiety or depressive disorders was quantified using odds ratios generated from logistic regression analyses and from a set of latent Markov analyses. We focus on longitudinal associations among narrowly defined DSM anxiety or depressive disorders. RESULTS: In simple logistic models, adolescent anxiety or depressive disorders predicted an approximate 2- to 3-fold increased risk for adulthood anxiety or depressive disorders. There was evidence of specificity in the course of simple and social phobia but less specificity in the course of other disorders. Results from the analyses using latent variables suggested that while most adolescent disorders were no longer present in young adulthood, most adult disorders were preceded by adolescent disorders. CONCLUSIONS: An anxiety or depressive disorder during adolescence confers a strong risk for recurrent anxiety or depressive disorders during early adulthood. Most anxiety and depressive disorders in young adults may be preceded by anxiety or depression in adolescence.

Mitochondrial DNA and Y chromosome-specific polymorphisms in the Seminole Tribe of Florida.

Mitochondrial DNA (mtDNA) sequence variation was examined in 37 Seminoles from Florida by polymerase chain reaction amplification and high resolution restriction endonuclease analysis. The Y chromosome TaqI restriction fragment length polymorphisms detected by the probes 49a, 49f, and 12f2 were examined in the 26 males of this group. Analysis of the mtDNA revealed that all four Native American haplogroups (A, B, C and D) were present in the Seminoles encompassing about 95% of the Seminole mtDNAs. No European mtDNAs were found among the Seminoles, but two mtDNAs (about 5%) were members of the African-specific haplogroup L1, thus indicating that a limited number of African women were incorporated in the Seminole tribe. Analysis of Y chromosome haplotypes supports the hypothesis that haplotypes 18 and 63 are the most likely founding Native American Y chromosome haplotypes from Asia. However, 11% of the Seminole Y chromosomes represented haplotypes generally attributed to Europeans, though none harbored standard African haplotypes. These findings support historical evidence that the Seminole tribe has integrated individuals of European and African ancestry, but suggests that the sex ratio of nonnatives from different continents may have varied.

(-)-Spiro[1-azabicyclo[2.2.2]octane-3,5'-oxazolidin-2'-one], a conformationally restricted analogue of acetylcholine, is a highly selective full agonist at the alpha 7 nicotinic acetylcholine receptor.

Neuronal nicotinic acetylcholine receptors are members of the ligand-gated ion channel receptor superfamily and may play important roles in modulating neurotransmission, cognition, sensory gating, and anxiety. Because of its distribution and abundance in the CNS, the alpha 7 nicotinic receptor is a strong candidate to be involved in some of these functions. In this paper we describe the synthesis and in vitro profile of AR-R17779, (-)-spiro[1-azabicyclo[2.2. 2]octane-3,5'-oxazolidin-2'-one] (4a), a potent full agonist at the rat alpha 7 nicotinic receptor, which is highly selective for the rat alpha 7 nicotinic receptor over the alpha 4 beta 2 subtype. Preliminary SAR of AR-R17779 presented here indicate that there is little scope for modification of this rigid molecule as even minor changes result in significant loss of the alpha 7 nicotinic receptor affinity.

Mitochondrial DNA sequence analysis of four Alzheimer's and Parkinson's disease patients.

The mitochondrial DNA (mtDNA) sequence was determined on 3 patients with Alzheimer's disease (AD) exhibiting AD plus Parkinson's disease (PD) neuropathologic changes and one patient with PD. Patient mtDNA sequences were compared to the standard Cambridge sequence to identify base changes. In the first AD+PD patient, 2 of the 15 nucleotide substitutions may contribute to the neuropathology, a nucleotide pair (np) 4336 transition in the tRNA(Gln) gene found 7.4 times more frequently in patients than in controls, and a unique np 721 transition in the 12S rRNA gene which was not found in 70 other patients or 905 controls. In the second AD+PD patient, 27 nucleotide substitutions were detected, including an np 3397 transition in the ND1 gene which converts a conserved methionine to a valine. In the third AD+PD patient, 2 polymorphic base substitutions frequently found at increased frequency in Leber's hereditary optic neuropathy patients were observed, an np 4216 transition in ND1 and an np 13708 transition in the ND5 gene. For the PD patient, 2 novel variants were observed among 25 base substitutions, an np 1709 substitution in the 16S rRNA gene and an np 15851 missense mutation in the cytb gene. Further studies will be required to demonstrate a causal role for these base substitutions in neurodegenerative disease.

Benzodiazepine site inverse agonists can selectively inhibit subtypes of the GABAA receptor.

Using the two-electrode voltage-clamp technique, we have evaluated the effects of several inverse agonists on GABA current amplitude in Xenopus oocytes. Oocytes were injected with cRNA coding for primate alpha 1, alpha 2, or alpha 3 subunits in combination with beta 1 gamma 2, beta 2 gamma 2, or beta 3 gamma 2 subunits. In the presence of CGS 8216, we observed greater inhibition in alpha 1 beta 1 gamma 2, alpha 1 beta 2 gamma 2, alpha 1 beta 3 gamma 2, and alpha 3 beta 1 gamma 2 subunit combinations than in other subunit combinations (p < 0.022). DMCM also showed subunit selective inhibition (p < 0.035) whereas FG 7142 did not (p > 0.075). The above findings indicate that drug structure, alpha subunits, and beta subunits interact to influence the magnitude of inhibition of GABAA R subtypes.

Alpha subunits influence Zn block of gamma 2 containing GABAA receptor currents.

The two-electrode voltage-clamp technique was used to evaluate Zn block of current activated by gamma-aminobutyric acid (GABA) in Xenopus oocytes injected with cRNA coding for alpha 1 beta 3 gamma 2, alpha 2 beta 3 gamma 2, or alpha 3 beta 3 gamma 2 subunits of the GABAA receptor (GABAAR). cDNA coded for the human form of alpha 1, alpha 2, beta 3 and gamma 2L subunits. alpha 3 subunit cDNA was obtained from an African green monkey library. Zn significantly inhibited the current evoked by application of GABA. Maximal inhibition was greater in alpha 2- and alpha 3- containing GABAARs than in alpha 1-containing GABAARs (51 +/- 1% and 53 +/- 2% vs 19 +/- 2%, respectively). The IC50 for Zn was smaller in alpha 1 than in alpha 2 or alpha 3 GABAARs (1.2 +/- 0.3 microM vs 7 +/- 1 and 9 +/- 1 microM, respectively). Zn shifted the concentration-response curve of GABA to the right in a parallel manner. These data suggest that Zn reduces the amplitude of current evoked at gamma 2 subunit containing GABAARs through an allosteric mechanism.

Nicotinic agonists competitively antagonize serotonin at mouse 5-HT3 receptors expressed in Xenopus oocytes.

The 5-HT3 receptor (5-HT3R) is part of a superfamily of ligand-gated ion channels which includes nicotinic acetylcholine receptors (nAChR). cRNA derived from the long isoform cloned mouse 5-HT3R was used to drive expression of 5-HT3Rs in Xenopus oocytes. 5-HT-induced currents were monitored using two-electrode voltage-clamp. Eight nicotinic agonists, including ACh and nicotine, but not alpha-anatoxin, were found to antagonize 5-HT-induced currents. With the exception of 3-(2,4)-dimethoxybenzylidene-anabaseine (DMXB-anabaseine; GTS-21) this antagonism appeared to be competitive since it could be overcome by increasing concentrations of 5-HT. Potency of 5-HT3 antagonism was comparable to reported values for nAChR alpha7 activation. These results confirm the notion of families of receptors and further indicate that strong similarities can exist in some critical binding domains.

Discriminating depression and anxiety in youth: a role for diagnostic criteria.

OBJECTIVE: To test the hypothesis that anxiety and depression in youth, as in adults, become increasingly discriminable when youth meet criteria for an emotional disorder. METHOD: The study uses cross-sectional data at two points in time from a large (n = 776) community sample of youths, aged eight to twenty. Associations between major depression and five anxiety disorders (overanxious, obsessive compulsive and separation anxiety disorders, and social and simple phobias) are examined by symptom scale and diagnosis. RESULTS: Anxiety and depression are moderately correlated, and substantially comorbid by diagnostic category. Symptoms are more discriminable among youths with diagnoses of at least one emotional disorder than among those without. A single factor accounts for symptoms among the non-diagnosed but multiple factors are required for the diagnosed group. CONCLUSIONS: Anxiety and depression are discriminable among youth who meet criteria for a specific emotional disorder but more highly associated among youths without such a diagnosis. This suggests that in youth, as has been shown in adults, depression and anxiety become increasingly discriminable as emotional psychopathology becomes more severe.

Comparative use of biomedical services and traditional healing options by American Indian veterans.

OBJECTIVE: This study described service use among American Indian veterans, compared use patterns across biomedical care and traditional healing options, and tested whether utilization varied as a function of need or availability. METHODS: A cross-sectional survey of 621 male combat veterans selected from tribal rolls was conducted between 1992 and 1995 in American Indian reservation communities in the Southwest and in the Northern Plains. Measures included assessments of demographic characteristics, physical and mental health conditions, and self-reports of any use during the past year of Veterans Administration (VA), Indian Health Service (IHS), and other biomedical services as well as participation in traditional ceremonies and use of indigenous healing options. RESULTS: Tribal groups were similar in sociodemographic characteristics and in number of health problems and mental and substance use problems during the past year. The same types of services from IHS were available to the two groups, and the geographic distance to these services was similar. VA facilities were more readily available in the Northern Plains than in the Southwest, where they were far from reservation boundaries. Use of IHS services was similar for the two tribal groups, but use of VA services was significantly less in the Southwest. Overall, biomedical services were used more in the Northern Plains, reflecting greater use of VA facilities. However, these differences in overall health service disappeared when traditional healing options were considered. Use of traditional healing was greater in the Southwest, offsetting lower biomedical service use. CONCLUSIONS: When the full array of options is examined, service use functions according to need for health care, but the kind of services used varies according to availability.

Psychosocial predictors of maternal depressive symptoms, parenting attitudes, and child behavior in single-parent families.

The purposes of the study were to identify psychosocial predictors of depressive symptoms among low-income, single mothers and to investigate the effects of maternal psychosocial factors, depressive symptoms, and parenting attitudes on children's behavior. In-home interviews were conducted with 225 mothers to obtain data on their everyday stressors, coping strategies, social resources, depressive symptoms, and parenting attitudes, as well as reports of their children's behavior. High depressive symptoms occurred among 59.6% of the women. Higher depressive symptoms were associated with greater everyday stressors, fewer social resources, and greater use of avoidance coping. Neither social resources nor coping strategies buffered the relationship between everyday stressors and depressive symptoms. Maternal depressive symptoms predicted parenting attitudes. Parenting attitudes, in turn, predicted child behavior. These findings suggest that depressive symptoms are indirectly associated with mothers' reports of child behavior through their influence on parenting attitudes.

Cloning of the cDNA and gene of mouse mast cell protease-6. Transcription by progenitor mast cells and mast cells of the connective tissue subclass.

The cDNA and gene for mouse mast cell protease-6 (MMCP-6) have been sequenced and show MMCP-6 to be translated as a prepro-enzyme with a 21-amino acid hydrophobic leader peptide, a 10-amino acid activation peptide, and a 245-amino acid mature enzyme. The mature form of the enzyme has 73% amino acid sequence identity with human and dog mast cell tryptases. The MMCP-6 gene includes 6 exons, with a total span of 1.8 kilobases. A 208-base pair intron was defined which separates the 5'-untranslated sequence of MMCP-6 from the translation initiation codon, thereby presenting a gene organization which distinguishes tryptic serine proteases from chymotryptic serine proteases of the mast cell secretory granule. By RNA blot analysis with a gene-specific probe, MMCP-6 has a unique subclass distribution in being transcribed in mouse connective tissue mast cells but undetectable in mucosal mast cells. MMCP-6 is the first serine protease of any class to be shown to be significantly transcribed in progenitor, bone marrow-derived mast cells, which can reconstitute both mucosal mast cell and connective tissue mast cell populations in mast cell-deficient mice.

The association between Type A behavior and change in coronary risk factors among young adults.

The association of Type A/B behavior pattern and changes in blood pressure, total serum cholesterol, serum triglyceride, body mass, and smoking was estimated in a cohort of 375 young Black and White men and women from a rural county in Central Kentucky between 1978-79 and 1985-88. Type A participants experienced significant increases in systolic (2.90 +/- 1.29 mmHg) and diastolic (3.80 +/- 1.17 mmHg) blood pressure and in cigarette smoking (3.26 +/- 0.89 cigarettes per day) over the eight-year follow-up period, but Type B participants experienced no change. Type A and B individuals showed similar changes in total serum cholesterol, serum triglyceride, or body mass. Differences between behavioral types in blood pressure were present for women but not men, and for Blacks but not for Whites. These findings suggest a possible significance of the Type A pattern for the development of cardiovascular risk of young adults.

Human alpha and beta subunits contribute to the EC50 for GABA at the GABAA receptor expressed in Xenopus oocytes.

The GABAA receptor/ionophore complex (GABAAR) may be composed of at least alpha, beta, and gamma subunits. Alpha subunits can influence the concentration of GABA at which a half maximal current response is elicited (EC50). There are no data to suggest that beta subunits can also influence this pharmacological property of the GABAAR. We examined the influence of human derived beta and alpha subunits on the EC50 for GABA. Nine different subunit combinations were evaluated: alpha 1, alpha 2, alpha 3 in combination with beta 1 gamma 2, beta 2 gamma 2, and beta 3 gamma 2. cRNA coding for these subunit combinations was injected into Xenopus oocytes that were subsequently recorded from using the two electrode voltage-clamp technique. A two-way analysis of variance showed that both alpha and beta subunits interact to influence the EC50 of GABAARs. The EC50 for alpha 3 changed significantly with beta subunits. The EC50 for alpha 2 was significantly different in beta 3 compared to beta 1 and beta 2 subunits, while the EC50 for alpha 1 was not significantly different between beta subunits. These findings suggests that other pharmacological and physiological properties may also be determined by interactions between alpha and beta subunits.

Point mutations in the M2 region of the alpha, beta, or gamma subunit of the GABAA channel that abolish block by picrotoxin.

Site-directed mutagenesis and the two-electrode voltage-clamp techniques were used to evaluate the site of action of picrotoxin on rat alpha 1 beta 2 gamma 2 containing GABAA receptors expressed in Xenopus oocytes. Following a sequence comparison between GABAA subunits and the picrotoxin-insensitive glycine beta subunit, the following mutations were made near the center of the M2 region of the alpha 1, beta 2, and gamma 2 GABAA subunits: alpha 1(T261F/T267A), beta 2(T246F/T252A), and gamma 2(T271F/T277A). Wild type (alpha 1 beta 2 gamma 2) GABA channels had an IC50 for picrotoxin of 1.3 +/- O.3 microM. In contrast, alpha 1 beta 2 gamma 2 channels that contained any one of the mutated alpha 1, beta 2, or gamma 2 subunits produced currents that were insensitive to picrotoxin (0.1-100 microM). The single mutant beta 2(T246F), in combination with wild type alpha and gamma subunits, also conferred picrotoxin-insensitivity. In contrast, combinations containing beta 2(T252A) were blocked by picrotoxin with an IC50 of 1.4 +/- 0.4 microM. In some instances, the EC50 to GABA was slightly altered in the mutant receptors; but no change was observed in EC50 or potentiation by the allosteric modulator, alprazolam. The data in this study suggest that picrotoxin's site of action is within the channel pore; however the mechanism by which picrotoxin blocks current remains unknown.

Physicians' psychologic reactions to malpractice litigation.

A questionnaire investigating the psychologic sequelae of malpractice litigation was administered to sued and nonsued physicians through a major malpractice insurer in a rural southern state. Factor analysis showed clusters of symptoms, including psychologic trauma, job strain, shame/doubt, and active coping. Psychologic stress decreased with time (but did not return to baseline after 2 years), with winning a case, and with increased age. Stress was increased among those with cases pending or multiple suits. Female physicians used more active coping strategies, and being in a high-risk specialty led to greater job strain and active coping, regardless of litigation experience. Malpractice litigation is a major life trauma that should be dealt with as any other trauma, including use of positive coping strategies such as knowledge of the psychologic sequelae, cognitive reframing, and collegial and personal support systems.