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PubMed1989

Improving medical communication with facsimile (fax) transmission.

Facsimile machines (fax) used intensely in business, send copies of documents from one location to another. The medical potential for fax has not been fully explored. A general background in fax and the potential uses for fax between hospitals and within hospitals are described. Fax permits small hospitals to share the resources of larger hospitals and permits a large hospital to share resources more efficiently among its departments. The cost of a fax unit is small compared with the amount of work and time it can save. Clinics and private physicians may also find fax units cost effective. Fax boards, which provide fax capability to personal computers, are also described. The use of fax could streamline the process of patient transfer, telephone patient consultation, medical records retrieval, ECG interpretation, central information distribution, retrieval of medical literature, inpatient pharmacy orders, etc.

Copying Processes↗

PubMed2004

A model to facilitate reflective thinking in clinical nursing education.

A qualitative, contextual, exploratory and descriptive design for theory generation was used to develop a model to facilitate reflective thinking in clinical nursing education (Mouton & Marais, 1990:43; Mouton, 1996: 103-109; Chinn & Kramer 1991:79-120). A model was developed within the existing frameworks of theory generation. Wilson (1963:23-39) and Gift (1997:75,76) provided a theoretical framework for a concept analysis of reflective thinking in phase one of the study. Further conceptual meaning was attained through a perceptual survey where twelve nurse educators participated in a focus group interview with regard to how reflective thinking can be facilitated in clinical nursing education. Classification of the main concepts and sub-concepts was made through a conceptualisation process within Dickoff, James and Wiedenbach's (1968:415-435) theoretical framework using the six elements of practice theory. Concluding relation statements were inferred through deductive analysis and synthesis after conceptualisation of each main concept. The relation statements provided the basis for model description (Chinn & Kramer, 1991:107-125). Definitions of the main concepts and sub-concepts were described using the basic rules by (Rossouw, 2001:10-11; Cohen & Copi, 1994:192-195). The adapted educational process from five learning theories provided a framework through which the procedure to facilitate reflective thinking in clinical nursing education was described. Lastly, the model was evaluated using the pre-determined criteria by Chinn and Kramer (1991:128-137) and refined by experts in qualitative research and theory generation. Guidelines were developed which do not form part of this article. Theoretical validity was ensured. Recommendations, limitations, challenging hypothesis and a conclusion were made.

Decision Making↗

PubMed1997

The mouse Plk gene: structural characterization, chromosomal localization and identification of a processed Plk pseudogene.

The Plk gene encodes a serine/threonine protein kinase believed to be important for the normal progression of mammalian cells through the cell cycle. In this paper, we report the genomic organization of the mouse Plk gene. The mouse Plk gene encompasses 16 kb of the mouse genome and is organised into 10 exons. Based on homology with the human PLK1 promoter region, the putative mouse promoter region includes a CCAAT motif but lacks the conventional TATA motif. The proposed promoter region contains consensus binding sites for several transcriptional regulators, including Sp1 and AP2. In addition to the active copy of Plk, Plk exists as a processed pseudogene. Using RFLP analysis, we have localized the active Plk gene to mouse Chromosome 7 and the processed pseudogene to mouse Chromosome 5. Southern blot analysis of DNA from a limited number of other mammalian species suggests that the duplication is confined to the mouse. Parsimony analysis suggests that the gene duplication leading to the mouse Plk pseudogene occurred after the rat-mouse split.

Animals↗

PubMed2006

A quantitative model of error accumulation during PCR amplification.

The amplification of target DNA by the polymerase chain reaction (PCR) produces copies which may contain errors. Two sources of errors are associated with the PCR process: (1) editing errors that occur during DNA polymerase-catalyzed enzymatic copying and (2) errors due to DNA thermal damage. In this study a quantitative model of error frequencies is proposed and the role of reaction conditions is investigated. The errors which are ascribed to the polymerase depend on the efficiency of its editing function as well as the reaction conditions; specifically the temperature and the dNTP pool composition. Thermally induced errors stem mostly from three sources: A+G depurination, oxidative damage of guanine to 8-oxoG and cytosine deamination to uracil. The post-PCR modifications of sequences are primarily due to exposure of nucleic acids to elevated temperatures, especially if the DNA is in a single-stranded form. The proposed quantitative model predicts the accumulation of errors over the course of a PCR cycle. Thermal damage contributes significantly to the total errors; therefore consideration must be given to thermal management of the PCR process.

Base Sequence↗

PubMed1988

Characterization, evolutionary relationships, and chromosome location of processed mouse HPRT pseudogene.

Studies on a cell line with amplified copies of the mouse hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene and HPRT gene transfer experiments revealed the existence of a nonfunctional HPRT-related sequence in the mouse genome. This sequence was isolated and found to be a processed HPRT pseudogene. With the exception of a small internal deletion, the pseudogene is believed to comprise a complete reverse transcript of HPRT mRNA, although the 3' end of the pseudogene was lost in the cloning process. A probe from a region flanking the mouse pseudogene was used to investigate the evolutionary relationships of mammalian HPRT pseudogenes. The pseudogenes in mouse and Chinese hamster appear to have a common origin, but no homology to any of the four known human HPRT pseudogenes was detected. A pseudogene-linked restriction fragment length polymorphism was used to map the pseudogene to the distal end of mouse chromosome 17.

Animals↗

PubMed2005

History of the Tfam gene in primates.

Tfam is a single copy nuclear gene mapping on chromosome 10 in human and mouse, 20 in rat and 12 in Presbytis cristata. It encodes for an HMG (high-mobility-group) protein showing a high affinity with the two transcriptional promoters and other mitochondrial DNA regions. It is an activator of mitochondrial transcription acting in the presence of mitochondrial RNA polymerase and of transcription factor B. Other interesting features of Tfam gene in human and rat are reported such as the existence of a smaller isoform, originated by an alternative splicing mechanism of the exon 5 (delta5 isoform) and the presence of different processed pseudogenes in addition to the active copy of the gene. In order to widen knowledge about Tfam gene and the appearance of some of its properties in the evolutionary history of primates, we have studied some aspects of this gene in different species. In particular we have determined its chromosomal localization, suggesting that its locus is highly conserved; we have searched for the presence of the delta5 isoform, demonstrating that it is present only in hominids; we have provided evidence of Tfam processed pseudogenes in the majority of the analysed genomes. Sequence data from this article have been deposited in the EMBL nucleotide database.

Animals↗

PubMed1995

The gray-scale ink-jet printer: value in making hard copies of digital images.

Referring physicians often are supplied with copies of images to illustrate a report of the findings of a radiologic study or so that the radiologist can retain the original images. The increasing costs of production, film, and recovery of chemicals have enhanced the requirement for a clean, low-cost dry printing process. An ink-jet gray-scale paper printer (Unitone, Scitex Medical Systems, Bedford, MA) can print high-quality (300 dots per inch [dpi]) images with an effective 10-bit gray scale range by using the Hertz continuous ink-jet method [1-3], which does not require the use of a darkroom or hazardous chemicals. Several types of media (matte paper, glossy paper, transparency film) with a printing area of 26.9 x 43.7 cm (10.6 x 17.4 inches) may be used. The consumables are approximately 50-70% less expensive than the cost of silver halide film, providing a cost advantage over film for referral and archival copies. The results of an initial evaluation of the ink-jet printer at our institution are reported here.

Computer Peripherals↗

PubMed2025

Assessing construct reliability through open-ended survey response analysis.

Online surveys often include quantitative attention checks, but inattentive participants might also be identified using their qualitative responses. We used the software Turnitin™ to assess the originality of open-ended responses in four mixed-method surveys that included validated multi-item rating scales (i.e., constructs). Across surveys, 18-35% of participants (n =  3,771) were identified as having copied responses from online sources. We assessed indicator reliability and internal consistency reliability and found that both were lower for participants identified as using copied text versus those who wrote more original responses. Those who provided more original responses also provided more consistent responses to the validated scales, suggesting that these participants were more attentive. We conclude that this process can be used to screen open-ended responses from online surveys. We encourage future research to replicate this screening process using similar tools, investigate strategies to reduce copying behaviour, and explore the motivation of participants to search for information online, including what sources they find compelling.

Adult↗

PubMed2006

Peroxisome biogenesis: where Arf and coatomer might be involved.

The present review summarizes recent observations on binding of Arf and COPI coat to isolated rat liver peroxisomes. The general structural and functional features of both Arf and coatomer were considered along with the requirements and dependencies of peroxisomal Arf and coatomer recruitment. Studies on the expression of mammalian Pex11 proteins, mainly Pex11alpha and Pex11beta, intimately related to the process of peroxisome proliferation, revealed a sequence of individual steps including organelle elongation/tubulation, formation of membrane and matrix protein patches segregating distinct proteins from each other, development of membrane constrictions and final membrane fission. Based on the similarities of the processes leading to cargo selection and concentration on Golgi membranes on the one hand and to the formation of peroxisomal protein patches on the other hand, an implication of Arf and COPI in distinct processes of peroxisomal proliferation is hypothesized. Alternatively, peroxisomal Arf/COPI might facilitate the formation of COPI-coated peroxisomal vesicles functioning in cargo transport and retrieval from peroxisomes to the ER. Recent observations suggesting transport of Pex3 and Pex19 during early steps of peroxisome biogenesis from the ER to peroxisomes inevitably propose such a retrieval mechanism, provided the ER to peroxisome pathway is based on transporting vesicles.

ADP-Ribosylation Factors↗

PubMed2004

Executive dysfunction and visuospatial ability among depressed elders in a community setting.

Visuospatial ability is frequently compromised among elderly depressed patients, but it is unclear whether the impairment is a consequence of a visuospatial memory deficit or of an executive dysfunction that impacts visuospatial ability. The Boston Qualitative Scoring System is a method of scoring the Rey-Osterrieth Complex Figure (ROCF) that assesses the process used to draw the figure, the executive aspect of the task, as well as the accuracy and location of the completed elements. The hypotheses that executive scores as measured by the BQSS would separate diagnostic groups and that executive function would mediate the relationship between depression and nonverbal recall were tested using a between groups design with elderly depressed volunteers (N = 31) and healthy controls (N = 31). Participants were screened for other Axis I disorders with the Structured Clinical Interview for DSM-IV Diagnosis, diagnosed for major depression per DSM-IV criteria, and administered the ROCF. The copy and recall drawings were scored using BQSS criteria, and scores were grouped into executive and drawing scores from both copy and recall phases. Executive scores during the copy phase and drawing scores from the recall phase separated the diagnostic groups [F(1,59), = 4.14, P = .05] and [F(1,59) = 6.88, P = .01], respectively. Follow-up ANCOVAS showed that copy Planning, the score that quantified the process by which the figure was drawn, separated the diagnostic groups. Planning also mediated the association between depression and the percent of the figure recalled after the short delay (Z = 1.84, P < .05). The significance of the depression-to-recall pathway was eliminated when Planning was controlled for, but Planning remained related to percent recalled [B = -6.90, P < .007]. A dimension of executive dysfunction, represented here by Planning, may be one underlying source of the observed decline in nonverbal recall among elderly depressed patients. This result is consistent with the theory that dysfunction of the prefrontal cortex is a critical feature of late-life depression.

Aged↗

PubMed2000

Evolution of different subfamilies of mariner elements within the medfly genome inferred from abundance and chromosomal distribution.

The abundance and distribution pattern of eight mariner elements from three different subfamilies in the genome of the medfly Ceratitis capitata were determined. The copy numbers, as determined by slot-blot analysis, were very different for these elements. Their abundance did not change significantly within the native, the ancient or the newly derived populations, indicating that the rapid colonization process of the medfly had not affected the copy number of mariner elements. The distribution of the mariner elements was analyzed using fluorescent in situ hybridization (FISH) with charge-coupled device (CCD) camera analysis. The pattern of distribution in euchromatin and heterochromatin varied greatly and was distinctive and specific for each element. The implications of these findings are discussed and it is concluded that they generally support the hypothesis of a transposition/selection model in which the abundance and distribution patterns of these elements are regulated primarily by selection against deleterious effects due to meiotic ectopic recombination, while genetic drift would have played a minor role.

Animals↗

PubMed1987

A model of evolution for accumulating genetic information.

By taking into account recent knowledge of multigene families and other repetitive DNA sequences, a model of evolution by gene duplication for accumulating genetic information is studied. Genetic information is defined as the sum of distinct functions that the gene family can perform. A coefficient, "genetic diversity" is defined and used in this study, that is highly correlated with genetic information. Initially, a multigene family with a few gene copies is assumed, and natural selection starts to work on this gene family to increase genetic diversity contained in the gene family. As an important mechanism, unequal crossing-over is incorporated. Together with mutation, it is responsible for supplying genetic variability among individuals for selection to work. A specific model, in which individuals with less genetic diversity are selectively disadvantageous, has been studied in detail. Through approximate theoretical analysis and extensive Monte Carlo studies, it has been shown that the system is an extremely efficient way to accumulate genetic information. For attaining one gene, the genetic load is much smaller under this model than under the traditional model of natural selection. The model may be applied to the process of origin of multigene families with diverse copy members such as those of immunoglobulin or cytochrome P450. In general, the process of creating new genes by duplication might be somewhere between the present and the traditional models.

Biological Evolution↗

PubMed1978

Effects of orienting tasks on recognition of chess positions.

Two experiments using a levels-of-processing paradigm were performed to demonstrate the existence and usefulness of a semantic component in chess knowledge. Experiment I compared forced-choice recognition of chess positions after a structural task (piece counting) as opposed to a semantic task (choosing a move). Recognition accuracy, confidence, and familiarity ratings all showed a facilitation effect in the semantic condition. By including an orienting task that did not encourage semantic processing but still allowed pattern-matching operations to occur (copying a board), Experiment II demonstrated that this task effect was a genuine enhancement of memory due to meaningful processing. One again, the processing of meaningful relations in the semantic task (positional evaluation) produced a higher level of recognition performance than did the more structural processing. These results suggest that aspects of meaning have some input into the processes that generate the memory representation of a chess position.

Cognition↗

PubMed1994

Human cytomegalovirus infection increases the number of ouabain-binding sites in human fibroblasts.

Infection of permissive human embryo fibroblasts (MRC-5) with human cytomegalovirus (HCMV) increased the number of copies of the Na+,K(+)-ATPase (the Na+ pump) in the plasma membrane, measured as ouabain-binding sites. The increase was preceded by cell enlargement by about 24 hr, becoming significant between 48 and 72 hr after infection. Reduction in Na+ or Cl- concentration in the culture media immediately after infection partially prevented the increase in the number of ouabain-binding sites. The effect was reversible upon restoring Cl- or Na+ to the incubation medium, but withdrawal of either ion at 24 or 48 hr PE failed to prevent the increase in the number of binding sites. These results suggest that the processes that resulted in the increase of copies of the Na+,K(+)-ATPase required both Na+ and Cl- during the first 24 hr PE. Amiloride and ethylisopropylamiloride, two inhibitors of Na+ transport mechanisms of the plasma membrane have been previously shown to reduce the amount of virus yields and to prevent the onset of cytomegaly (Fons et al., 1991, Proc. Soc. Exp. Biol. Med. 196, 89-96). We show here that these agents partially block the increase in ouabain-binding sites caused by HCMV infection.

Amiloride↗

PubMed2004

Effects of mutations in an HIV-1 gag gene containing a 107-codon tandem repeat in the matrix region on assembly and processing of the protein product.

It has been demonstrated previously that a human immunodeficiency virus (HIV) type 1 Gag mutant (MA2) with a tandem repeat of 107-matrix codons in the matrix domain could direct virus particle assembly and budding [Wang et al. (2000c): J Med Virol 61:423-432]. Since the regions involved functionally in HIV Gag assembly and transport have been mapped to the matrix domain, it was interesting to test the effects of the duplicated matrix-coding sequence on Gag assembly, transport, and virus processing of some assembly-defective HIV matrix mutants. In this study, a number of HIV matrix mutations were introduced into either the proximal or distal copy of the duplicated matrix-coding sequence. Assembly, release, processing, and subcellular localization of the Gag mutants were analyzed by transient expression in 293T cells. The result indicates that the budding defect of HIV matrix mutants could be moderately or significantly reversed when the additional 107-matrix codons were present; however, these matrix double mutations affected significantly the virus particle processing. Mislocalized matrix mutants could also be redistributed to a certain degree in the presence of the duplicated matrix copy. Although the subcellular distribution patterns of the matrix mutants did not correlate completely with the budding efficiency, the data suggest that the budding defect caused by the matrix mutations could be masked to some extent by the duplicated matrix coding sequence.

Cell Culture Techniques↗

PubMed2001

Replication slippage involves DNA polymerase pausing and dissociation.

Genome rearrangements can take place by a process known as replication slippage or copy-choice recombination. The slippage occurs between repeated sequences in both prokaryotes and eukaryotes, and is invoked to explain microsatellite instability, which is related to several human diseases. We analysed the molecular mechanism of slippage between short direct repeats, using in vitro replication of a single-stranded DNA template that mimics the lagging strand synthesis. We show that slippage involves DNA polymerase pausing, which must take place within the direct repeat, and that the pausing polymerase dissociates from the DNA. We also present evidence that, upon polymerase dissociation, only the terminal portion of the newly synthesized strand separates from the template and anneals to another direct repeat. Resumption of DNA replication then completes the slippage process.

Binding Sites↗

PubMed1995

Clinical aspects of direct digital mammography.

Since 1990, computed radiography (CR) has been used routinely in our symptomatic mammography service, imaging approximately 2,000 patients per year. Careful selection of the appropriate image processing parameters results in high-quality images of diagnostic value equivalent to conventional film-screen mammograms. Problems encountered included dust artifacts, black films, and white films, but these constituted only a very small proportion of images obtained and the remedies are discussed. Hard-copy reporting is used and improved image presentation is considered. New processing algorithms and the development of soft-copy reporting at dedicated workstations are expected in the near future.

Algorithms↗

PubMed2005

Transcribed processed pseudogenes in the human genome: an intermediate form of expressed retrosequence lacking protein-coding ability.

Pseudogenes, in the case of protein-coding genes, are gene copies that have lost the ability to code for a protein; they are typically identified through annotation of disabled, decayed or incomplete protein-coding sequences. Processed pseudogenes (PPsigs) are made through mRNA retrotransposition. There is overwhelming genomic evidence for thousands of human PPsigs and also dozens of human processed genes that comprise complete retrotransposed copies of other genes. Here, we survey for an intermediate entity, the transcribed processed pseudogene (TPPsig), which is disabled but nonetheless transcribed. TPPsigs may affect expression of paralogous genes, as observed in the case of the mouse makorin1-p1 TPPsig. To elucidate their role, we identified human TPPsigs by mapping expressed sequences onto PPsigs and, reciprocally, extracting TPPsigs from known mRNAs. We consider only those PPsigs that are homologous to either non-mammalian eukaryotic proteins or protein domains of known structure, and require detection of identical coding-sequence disablements in both the expressed and genomic sequences. Oligonucleotide microarray data provide further expression verification. Overall, we find 166-233 TPPsigs ( approximately 4-6% of PPsigs). Proteins/transcripts with the highest numbers of homologous TPPsigs generally have many homologous PPsigs and are abundantly expressed. TPPsigs are significantly over-represented near both the 5' and 3' ends of genes; this suggests that TPPsigs can be formed through gene-promoter co-option, or intrusion into untranslated regions. However, roughly half of the TPPsigs are located away from genes in the intergenic DNA and thus may be co-opting cryptic promoters of undesignated origin. Furthermore, TPPsigs are unlike other PPsigs and processed genes in the following ways: (i) they do not show a significant tendency to either deposit on or originate from the X chromosome; (ii) only 5% of human TPPsigs have potential orthologs in mouse. This latter finding indicates that the vast majority of TPPsigs is lineage specific. This is likely linked to well-documented extensive lineage-specific SINE/LINE activity. The list of TPPsigs is available at: http://www.biology.mcgill.ca/faculty/harrison/tppg/bppg.tov (or) http:pseudogene.org.

Amino Acid Sequence↗