Facial Recognition Task for the Classification of Mild Cognitive Impairment with Ensemble Sparse Classifier.

Conventional methods for detecting mild cognitive impairment (MCI) require cognitive exams and follow-up neuroimaging, which can be time-consuming and expensive. A great need exists for objective and cost-effective biomarkers for the early detection of MCI. This study uses a sequential imaging oddball paradigm to determine if familiar, unfamiliar, or inverted faces are effective visual stimuli for the early detection of MCI. Unlike the traditional approach where the amplitude and latency of certain deflection points of event-related potentials (ERPs) are selected as electrophysiological biomarkers (or features) of MCI, we used the entire ERPs as potential biomarkers and relied on an advanced machine-learning technique, i.e. an ensemble of sparse classifier (ESC), to choose the set of features to best discriminate MCI from healthy controls. Five MCI subjects and eight age-matched controls were given the MoCA exam before EEG recordings in a sensory-deprived room. Traditional time-domain comparisons of averaged ERPs between the two groups did not yield any statistical significance. However, ESC was able to discriminate MCI from controls with 95% classification accuracy based on the averaged ERPs elicited by familiar faces. By adopting advanced machine-learning techniques such as ESC, it may be possible to accurately diagnose MCI based on the ERPs that are specifically elicited by familiar faces.

Non-Invasive, Cost-Effective, Early Diagnosis of Mild Cognitive Impairment in an Outpatient Setting: Pilot Study.

Mild cognitive impairment (MCI) and Alzheimer's Disease (AD) affect millions worldwide, yet no curative treatments for these neuro-degenerative disorders have been developed to date. The current study aims to propose a noninvasive, cost-effective, early diagnostic protocol for individuals suffering with MCI in an outpatient setting. Elderly participants (n=11) were screened for MCI utilizing the Montreal Cognitive Assessment (MoCA) questionnaire preceding a visual stimuli task. Participants were presented with facial stimuli to elicit event related potentials (ERP) while their cortical activity was recorded utilizing electroencephalogram (EEG). Combining regional neurophysiological biomarkers into a multidimensional feature space allowed for differentiation between healthy and MCI participants based on their respective MoCA scores. This study illustrates the feasibility of recording reliable EEG in an outpatient setting while presenting a novel method for diagnosing MCI in elderly (age >60) populations.

Expression of the mitogen-activated protein kinase kinase ZmMEK1 in the primary root of maize.

We have analyzed changes in the distribution and abundance of a mitogen-activated protein kinase kinase (MAPKK) enzyme (EC 2.7.1.37) known as ZmMEK1. in root apices of Zea mays L. under normal growth conditions, and after treatments that alter patterns of proliferation, as a means to assess the potential physiological role of the MAP kinase cascade in growth and development. The ZmMEK1 protein is most abundant within immature tissues such as the roots and leaves of seedlings, and is nearly undetectable in mature leaf tissue. Along the longitudinal axis of growing roots, ZmMEK1 mRNA and protein are abundant throughout the apical 12 mm. Two anti-ZmMEK1 antibody-reactive proteins can be resolved within the apical 4 mm of the root, spatially coinciding with the meristem and distal elongation zone. Phosphatase treatments suggest that both immunoreactive bands are forms of ZmMEK1 that differ in their state of phosphorylation. Expression of ZmMEK1, histone H4 and cyclin-dependent protein kinase (CDK) in roots after 7 days of exposure to low temperature and during a 48-hour recovery period was monitored during the coincident alterations in growth. Levels of ZmMEK1 mRNA and protein within these roots were indistinguishable from those of control roots. However, a slower-migrating form of ZmMEK1 temporally coincided with the observed increase in CDK levels during the transition into proliferative activity. We demonstrate that the ZmMEK1 MAPK activator is expressed and is differentially phosphorylated within the root meristem and distal elongation zone. We suggest that post-translational modifications of the protein regulate the function of ZmMEK1 within the root. Changes in ZmMEK1 phosphorylation state correlate with changes in proliferation in the root apex.

Telehealth's impact on nursing and the development of the interstate compact.

The information age has opened a new era for nursing practice. Advances in telecommunications technology now allow nurses to care for patients and their families in geographic locations throughout the country. This new practice environment challenges many of the assumptions that have created a state-based system of nurse practice acts and licensing. In response to this challenge, the creation of a new mechanism for licensure and practice, the interstate compact, is developing. In this article, the development and regulatory challenges created by telenursing and the interstate compact are discussed.

Identification of a novel phosphorylation motif for CDPKs: phosphorylation of synthetic peptides lacking basic residues at P-3/P-4.

The Ca(2+)-dependent protein kinases (CDPKs) are members of a large subfamily of protein kinases in plants that have been implicated in the control of numerous aspects of plant growth and development. One known substrate of the CDPKs is the ER-located ACA2 calcium pump, which is regulated by phosphorylation of Ser(45). In the present study, a synthetic peptide based on the known regulatory phosphorylation site (RRFRFTANLS(45)KRYEA) was efficiently phosphorylated in vitro by CDPKs but not a plant SNF1-related protein kinase. Phosphorylation of the Ser(45)-ACA2 peptide was surprising because the sequence lacks basic residues at P-3/P-4 (relative to the phosphorylated Ser at position P) that are considered to be essential recognition elements for CDPKs. We demonstrate that phosphorylation of the Ser(45)-ACA2 peptide is dependent on the cluster of basic residues found N-terminal (P-6 to P-9) as well as C-terminal (P + 1/P + 2) to the phosphorylated Ser. The results establish a new general phosphorylation motif for CDPKs: [Basic-Basic-X-Basic]-phi-X(4)-S/T-X-Basic (where phi is a hydrophobic residue). The motif predicts a number of new phosphorylation sites in plant proteins. Evidence is presented that the novel motif may explain the phosphorylation by CDPKs of Ser271 in the aquaporin PM28A.

Octamer-primed sequencing technology: effects of dNTP supplementation.

Octamer-primed sequencing is a directed DNA sequencing strategy that employs the use of a presynthesized octamer primer library. Together with electronic octamer sequencing technology (eOST) it provides a faster, less expensive way to obtain DNA sequence information and can be used as a valuable tool for gap closure in large-scale genomic sequencing. In this paper we discuss the effect of dGTP/TTP supplementation on octamer sequencing. We show that addition of 75 microM dGTP and 5 microM TTP can improve the sequencing success rate by increasing the length and accuracy of generated sequence information. We also discuss the effect of template base composition immediately downstream of the octamer primer on the outcome of octamer sequencing.

Survey of transcripts in the adult Drosophila brain.

BACKGROUND: Classic methods of identifying genes involved in neural function include the laborious process of behavioral screening of mutagenized flies and then rescreening candidate lines for pleiotropic effects due to developmental defects. To accelerate the molecular analysis of brain function in Drosophila we constructed a cDNA library exclusively from adult brains. Our goal was to begin to develop a catalog of transcripts expressed in the brain. These transcripts are expected to contain a higher proportion of clones that are involved in neuronal function. RESULTS: The library contains approximately 6.75 million independent clones. From our initial characterization of 271 randomly chosen clones, we expect that approximately 11% of the clones in this library will identify transcribed sequences not found in expressed sequence tag databases. Furthermore, 15% of these 271 clones are not among the 13,601 predicted Drosophila genes. CONCLUSIONS: Our analysis of this unique Drosophila brain library suggests that the number of genes may be underestimated in this organism. This work complements the Drosophila genome project by providing information that facilitates more complete annotation of the genomic sequence. This library should be a useful resource that will help in determining how basic brain functions operate at the molecular level.

Similarities and differences in the conformation of protein-DNA complexes at the U1 and U6 snRNA gene promoters.

Most small nuclear RNAs (snRNAs) are synthesized by RNA polymerase II, but U6 snRNA is synthesized by RNA polymerase III. In the fruit fly Drosophila melanogaster the RNA polymerase specificity of the snRNA genes is determined by a few nucleotide differences within the proximal sequence element (PSE), a conserved sequence located approximately 40-65 bp upstream of the transcription start site. The PSE is essential for transcription of both RNA polymerase II-transcribed and RNA polymerase III-transcribed snRNA genes and is recognized in Drosophila by a multi-subunit protein factor termed DM:PBP. Previous studies that employed site-specific protein-DNA photocrosslinking indicated that the conformation of the DNA-protein complex is different depending upon whether DM:PBP is bound to a U1 or U6 PSE sequence. These conformational differences of the complex probably represent an early step in determining the selection of the correct RNA polymerase. We have now obtained evidence that DM:PBP modestly bends the DNA upon interacting with the PSE and that the direction of DNA bending is similar for both the U1 and U6 PSEs. Under the assumption that DM:PBP does not significantly twist the DNA, the direction of the bend in both cases is toward the face of the DNA helix contacted by the 45 kDa subunit of DM:PBP. Together with data from partial proteolysis assays, these results indicate that the conformational differences in the complexes of DM:PBP with the U1 and U6 PSEs more likely occur at the protein level rather than at the DNA level.

Octamer-primed sequencing technology: development of primer identification software.

Octamer sequencing technology (OST) is a primer-directed sequencing strategy in which an individual octamer primer is selected from a pre-synthesized octamer primer library and used to sequence a DNA fragment. However, selecting candidate primers from such a library is time consuming and can be a bottleneck in the sequencing process. To accelerate the sequencing process and to obtain high quality sequencing data, a computer program, electronic OST or eOST, was developed to automatically identify candidate primers from an octamer primer library. eOST integrates the base calling software PHRED to provide a quality assessment for target sequences and identifies potential primer binding sites located within a high quality target region. To increase the sequencing success rate, eOST includes a simple dynamic folding algorithm to automatically calculate the free energy and predict the secondary structure within the template in the vicinity of the octamer-binding site. Several parameters were found to be important, including base quality threshold, the window size of the template sequence segment, and the threshold [Delta] G value. OST, coupled with the eOST software, can be used to sequence short DNA fragments or in the finishing assembly stage of large-scale sequencing of genomic DNA.

Effects of psychological distress on blood pressure in adolescents.

This cross-sectional survey measured relationships among blood pressure and measures of psychologic distress, family structure, and economic status in a sample of adolescents exposed to Hurricane Hugo. Spielberger's Anger Scale and Derogatis' Brief Symptom Inventory were used. Data analysis revealed 5% of the 1079 adolescents were hypertensive. Multiple regression analyses revealed the following predictors of higher diastolic blood pressure: African-American race, recipient of subsidized lunch, exposure to Hurricane Hugo, and higher anger-in scores in males. The effects of a catastrophic event such as a hurricane on blood pressure and the effects of introjected anger have implications for both health care consumers and providers.

Guanine-rich telomeric sequences stimulate DNA polymerase activity in vitro.

Guanine-rich oligonucleotides and short telomeric DNA sequences can self-associate into G-quartet stabilized complexes. We discovered that this self-association can occur in sequencing reactions and that higher-order structures stimulate DNA polymerase to synthesize extended DNA strands. Base analogues were used to identify Hoogsteen base pairings as stabilizing forces in these stimulatory DNA structures. Scanning force microscopy confirmed that quartet-DNA was formed from these oligomers and that these extended, four-stranded structures could be bound by DNA polymerase. Since guanine quartet-stabilized structures are proposed to exist in vivo, such structures may stimulate DNA polymerization in vivo.

A polyadenylylation-specific RNA-contact site on the surface of the bifunctional vaccinia virus RNA modifying protein VP39 that is distinct from the mRNA 5' end-binding "cleft".

VP39 is a bifunctional mRNA-modifying protein that acts as both an mRNA cap-specific 2'-O-methyltransferase and a processivity factor for VP55, the vaccinia poly(A) polymerase catalytic subunit. Although regions of the protein surface required for methyltransferase function are well defined, it has been unclear whether the protein polyadenylylation function requires direct RNA contact and, if so, where the contact site(s) might be located on the protein surface. Here, we show that the VP55-VP39 heterodimer forms a stable complex with a 50mer oligonucleotide bearing a U2-N25-U motif, as opposed to the U2-N15-U motif that is optimal for stable complex formation with VP55 alone. An oligonucleotide bearing a U2-N25-U motif in which the downstream U residue is replaced with 4thioU can be efficiently photocrosslinked to VP39, but only in the context of the VP55-VP39 heterodimer. By partial proteolysis of end-labeled VP39, the site of oligonucleotide photocrosslinking was localized to the region of VP39 between residues Lys90 and Arg122. Peptide microsequencing and confirmatory mutagenesis identified the side-chain of Arg107 as the photocrosslinking site. Substitution of this residue with lysine abolished photocrosslinking entirely, consistent with the established RNA binding role of arginine in other RNA-binding proteins. This study provides clear evidence for a polyadenylylation-specific RNA-contact site on the surface of VP39, which is distinct from the RNA-binding methyltransferase "cleft" characterized in recent crystallographic and biochemical studies.

Effects of traumatic events, social support, and self-efficacy on adolescents' self-health assessments.

The purpose of this study was to examine the relationship between adolescents' exposure to traumatic events and their self-health assessments, and to examine the protective effects of social support and self-efficacy on this relationship. Survey results (N = 1,427) indicated that experiencing violent and nonviolent negative life events and being exposed to a disaster were inversely associated with adolescents' positive health assessments. As social support and self-efficacy decreased, adolescents' health assessments worsened. Female and Black adolescents had less favorable health assessments than their male and White counterparts. Findings suggest that traumatic events are predictive of adolescents' health assessments and that social support and self-efficacy prevent adolescents' health assessments from declining following traumatic events.

Molecular cloning and characterization of maize ZmMEK1, a protein kinase with a catalytic domain homologous to mitogen- and stress-activated protein kinase kinases.

Mitogen- or stress-activated protein kinase kinases (M/SAPKKs) are dual-specificity protein kinases that are components of highly conserved signal transduction pathways. A cDNA clone (ZmMEK1) was isolated from a Zea mays (L.) root tip library. ZmMEK1 contains a complete open reading frame, encoding a 355-amino-acid protein with an estimated molecular mass of 39,874 Da. The predicted protein contains the 11 catalytic sub-domains conserved in all protein kinases, and a version of the sub-domain VIII S/TxxxS/TxVGT motif that is characteristic of M/SAPKK proteins (EC 2.7.1.37). The catalytic domain of ZmMEK1 is most closely related (65% identity) to the tomato M/SAPKK homolog LeMEK1, but exhibits similar identity (39-60%) to M/SAPKKs from other plants, animals and fungi. Northern blotting revealed ZmMEK1 mRNA in maize seedling roots and coleoptiles; in mature plants transcripts were detected in stems and low levels in leaves. Transcription of ZmMEK1 mRNA was also affected by environmental stimuli. The catalytic domain of ZmMEK1 was expressed as a glutathione-S-transferase (GST) fusion protein in Escherichia coli. Nanogram quantities of the purified fusion protein reacted with anti-M/SAPKK antibodies on immunoblots. In vitro, the GST-ZmMEK1 fusion protein undergoes autophosphorylation, and will phosphorylate myelin basic protein, but will not phosphorylate histone H1. ZmMEK1 encodes an enzyme that is structurally and functionally similar to other M/SAPKK proteins.

DNA recognition properties of the N-terminal DNA binding domain within the large subunit of replication factor C.

Replication Factor C (RFC) is a five-subunit protein complex required for eukaryotic DNA replication and repair. The large subunit within this complex contains a C-terminal DNA binding domain which provides specificity for PCNA loading at a primer-template and a second, N-terminal DNA binding domain of unknown function. We isolated the N-terminal DNA binding domain from Drosophila melanogaster and defined the region within this polypeptide required for DNA binding. The DNA determinants most efficiently recognized by both the Drosophila minimal DNA binding domain and the N-terminal half of the human large subunit consist of a double-stranded DNA containing a recessed 5' phosphate. DNA containing a recessed 5' phosphate was preferred 5-fold over hairpined DNA containing a recessed 3' hydroxyl. Combined with existing data, these DNA binding properties suggest a role for the N-terminal DNA binding domain in the recognition of phosphorylated DNA ends.

Octamer-primed cycle sequencing using dye-terminator chemistry.

Octamer Sequencing Technology, OST, is a method of DNA sequencing using single octamer oligonucleotides to prime cycle sequencing reactions. This sequencing strategy is faster than a traditional primer-walking strategy, since access to this optimized octamer library eliminates delays associated with designing and synthesizing gene specific primers. In this report, OST has been optimized for fluorescent, dye-terminator cycle sequencing reactions to facilitate parallel processing of samples. The successful adaptation of OST to an automated sequencing platform and the design of and access to an octamer library are critical steps towards developing an efficient 'closed-loop' DNA sequencing system.