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PubMed1999

The logic of play in psychoanalysis.

The paper puts forward the idea that play is at work all the time in psychoanalysis. The play element functions continuously to sustain a paradoxical reality where things may be real and not real at the same time. This paradox is what allows the work of psychoanalysis to take place. The concept of play covers different activities with complex interrelations, and general definitions may be misleading. The essential element is the framework that makes the paradoxical reality possible. The logical structure of the play framework is investigated, and the paper clarifies the relations between the play frame, transference and enactment. Play and humour are compared. Spontaneity is the essence of both, and the criterion for analytic validity in both cases is whether they deepen the analytic process. The tragic and ironic aspects of psychoanalysis are related to the intrinsic connection between play and loss. The relation between play and games is discussed. The rule-bound quality of games can block more exploratory kinds of play, but it may be necessary to accept this, in order for analysis to feel safe enough. Clinical material illustrates the importance of the play framework, both in a case marked by prolonged hostile and negative states of mind, and in others where more straightforward playfulness was possible.

Hostility↗

PubMed2005

[Health monitoring on a federal level. Approaches and perspectives].

An assessment of the existing elements of a health monitoring system in Germany is given. Based on the analysis of deficits, the necessity for a comprehensive health monitoring system is recognised. The authors suggest starting points for the development of such a system in Germany by integrating different actors and taking into account different interests. The proposed system is based on a modular principle and allows for continuity as well as flexibility. As one key element in this monitoring system, a longitudinal health study is suggested, which allows the observation of developments in health matters as well as the evaluation of health policy actions. A plan for the step-wise development and testing of the health monitoring system is presented. Cooperation and data networking are essential elements. Whereas the flexible parts of the monitoring system should be financed by interested partners and customers, a basic sustainable financial support is a prerequisite. This paper provides arguments for the implementation of a health monitoring system and the need for long-term funding.

Cohort Studies↗

PubMed2002

Possible involvement of copper(II) in Alzheimer disease.

The beta-amyloid (Abeta) peptide is a principal component of insoluble amyloid plaques that are characteristic neuropathological features of Alzheimer disease (AD). The amyloid peptide also exists as a normal soluble protein that undergoes a pathogenic transition to an aggregated, fibrous form. This transition can be affected by extraneous proteinaceous elements and nonproteinaceous elements such as copper ions, which may promote aggregation and/or stabilization of the fibrils. Copper has been found in abnormally high concentrations in amyloid plaques and AD-affected neuropil, and copper-selective chelators have been shown to dissolve Abeta peptide from postmortem brain specimens. Although Cu(2+) is an essential element for life and the function of numerous enzymes is basic to neurobiology, free or incorrectly bound Cu(2+) can also catalyze generation of the most damaging radicals, such as hydroxyl radical, giving a chemical modification of the protein, alternations in protein structure and solubility, and oxidative damage to surrounding tissue.

Alzheimer Disease↗

PubMed2005

Nondestructive pollution exposure assessment in the European hedgehog (Erinaceus europaeus): I. Relationships between concentrations of metals and arsenic in hair, spines, and soil.

Conventional metal exposure assessment in terrestrial mammals is generally based on organ analyses of sacrificed animals. Few studies on mammals use nondestructive methodologies despite the growing ethical concern over the use of destructive sampling. Nondestructive methods involve minimal stress to populations and permit successive biomonitoring of the same populations and individuals. In the present study we assessed metal exposure of hedgehogs (Erinaceus europaeus) by investigating relationships between concentrations of metals (Ag, Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) and As in soil samples and in hair and spines of hedgehogs. Samples were collected in seven study sites along a metal pollution gradient, characterized by decreasing total soil Ag, As, Cd, Cu, Ni, and Pb concentrations with increasing distance from a nonferrous metallurgic factory. For a number of elements, soil contamination was related both to distance to the smelter and to habitat. Soil concentrations were positively related to levels in hair and spines for Ag, As, Cd, and Pb and thus to hedgehog exposure. Metal concentrations in soil did not relate to metal concentrations in hair and spines for essential elements (e.g., Cu, Fe, Mn, Ni, and Zn), except Co in hair and soil. Our results demonstrate that, at least for nonessential elements, concentrations in soils can be used to predict contamination of these elements in hedgehogs or vice versa. Furthermore, hedgehog exposure increased toward the smelter and was higher for hedgehogs foraging in grasslands than for animals foraging in the forest. Moreover, we believe that hair and spines are promising tools in terrestrial wildlife exposure assessment studies of metals and As.

Analysis of Variance↗

PubMed2005

Acquisition of a stable structure by yeast ribosomal P0 protein requires binding of P1A-P2B complex: in vitro formation of the stalk structure.

Saccharomyces cerevisiae ribosomal stalk consists of five proteins: P0 protein, with molecular mass of 34 kDa, and four small, 11 kDa, P1A, P1B, P2A and P2B acidic proteins, which form a pentameric complex P0-(P1A-P2B)/(P1B-P2A). This structure binds to a region of 26S rRNA termed GTPase-associated domain and plays a crucial role in protein synthesis. The consecutive steps leading to the formation of the stalk structure have not been fully elucidated and the function of individual P-proteins in the assembling of the stalk and protein synthesis still remains elusive. We applied an integrated approach in order to examine all the P-proteins with respect to stalk assembly. Several in vitro methods were utilized to mimic protein self-organization in the cell. Our efforts resulted in reconstitution of the whole recombinant stalk in solution as well as on the ribosomal particle. On the basis of our analysis, it can be inferred that the P1A-P2B protein complex may be regarded as the key element in stalk formation, having structural and functional importance, whereas P1B-P2A protein complex is implicated in regulation of stalk function. The mechanism of quaternary structure formation could be described as a sequential co-folding/association reaction of an oligomeric system with P0-(P1A-P2B) protein complex as an essential element in the acquisition of a stable quaternary structure of the ribosomal stalk. On the other hand, the P1B-P2A complex is not involved in the cooperative stalk formation and our results indicate an increased rate of protein synthesis due to the latter protein pair.

Dimerization↗

PubMed2003

Critical analysis of clinical research reporting in pediatric surgery: justifying the need for a new standard.

BACKGROUND/PURPOSE: Clinical practice in surgery relies heavily on observational data in which accurate and nonbiased reporting is critical. This study aims to assess the adequacy of clinical research reporting in pediatric surgery and to develop a means to raise the standard of such reporting. METHODS: The authors analyzed all observational studies published in The Journal of Pediatric Surgery from 1997 to 2002 (n = 300). Studies were assessed for 16 baseline criteria essential for the nonbiased reporting of clinical data (details regarding surgeons, cases, interventions, and statistical methods). Seven additional criteria pertaining to comparison methods were assessed in studies using controls. RESULTS: Ninety-five percent of all studies were retrospective, and only 25% utilized a control group. Most studies met less than half of the essential reporting criteria (mean, 7.6 of 16 baseline criteria; 3.3 of 7 comparison criteria). Reporting deficiencies were found in all major aspects of study design and statistical analysis. CONCLUSIONS: More rigorous reporting of clinical data in pediatric surgery could increase the clinical utility of published results. The authors have identified the fundamental elements essential to nonbiased reporting of clinical research data in surgery. Implementation of mandatory peer-review guidelines based on these principles could set a new standard for clinical reporting in surgery.

Bibliometrics↗

PubMed1998

Characterization of HSE sequences in human Hsp40 gene: structural and promoter analysis.

We have recently cloned a gene of Hsp40, a human homologue of bacterial DnaJ. Here we describe the structural and promoter analysis of human Hsp40 gene. Analysis of Hsp40 transcripts by 5' and 3' RACE suggested that they have different 3' ends, and primer extension studies revealed that the major transcription initiation site was localized 47 bp upstream of the ATG translation initiation codon. Promoter analysis using deletion derivatives defined a minimal region which was active in response to heat shock. The region contained the consensus heat shock element (HSE) sequences. The factor bound to these sequences was suggested to be a heat shock factor 1 (HSF1) by gel mobility supershift assay. In vivo footprinting and promoter analysis revealed that the HSEs in 5' upstream region of human Hsp40 gene were composed of eight contiguous (A/G)GAAN motifs and were essential for heat shock response. These results indicate that Hsp40 is a real heat shock protein. It is also shown that the HSE found in the first intron might not be the essential element for heat shock response.

Base Sequence↗

PubMed1995

Transcriptional regulation of the cholesteryl ester transfer protein gene by the orphan nuclear hormone receptor apolipoprotein AI regulatory protein-1.

We have defined a 105-base pair tissue-restricted promoter for the cholesteryl ester transfer protein (CETP) gene that contains a nuclear hormone receptor response element essential for transcriptional activity. DNaseI protection and electrophoretic mobility shift assays showed specific binding of nuclear extracts from HepG2 (hepatic) and Caco-2 (intestinal) cells (expressing cell types) to 3 sites (designated A (-26 to -57), B (-59 to -87), and C (-93 to -118)) within the 105-base pair minimal promoter element between -138 and -33. Mutagenesis studies indicated that the function of the promoter was dependent upon synergistic interactions between transcription factors bound to these sites. Mutation of site C reduced transcription by 50 and 80%, respectively, in HepG2 and Caco-2 cells, and electrophoretic mobility shift assays showed that nuclear hormone receptors, including ARP-1 and its homologue Ear-3/COUP-TF, were occupants of site C in both of these cell types. Overexpression of ARP-1 or Ear-3/COUP-TF with CETP promoter/chloramphenicol acetyltransferase gene reporter plasmids repressed transcriptional activity of the CETP promoter containing sequences up to -300, but activated transcription in the context of larger constructs containing sequences up to -636. Thus ARP-1 may assume a dichotomous role as both a transcriptional repressor and a transcriptional activator dependent on the promoter context. In addition, the architecture of the CETP gene promoter suggests that its expression is under the control of multiple transcriptional signaling pathways mediated by inducible transcription factors as well as nuclear hormone receptors.

3T3 Cells↗

PubMed1996

Full genetic rescue of adenosine deaminase-deficient mice through introduction of the human gene.

We have shown recently that adenosine deaminase (ADA)-deficient mice die perinatally with severe liver cell degeneration. In addition to enzyme substitution, we report the restoration of viability through introduction of the human ADA gene. The ADA gene is subject to complex developmental and tissue-specific regulation. To include the cis-regulatory elements necessary for correct regulation of the human ADA gene, a large transgenic locus constituting the human ADA gene with 10 kb of 5' and 4 kb of 3' flanking sequences was generated by co-injection of two overlapping DNA fragments into murine zygotes. Probably as a result of extrachromosomal (homologous) recombination between the fragments, one of the two transgenic lines contained a reconstituted, functional human ADA gene. As in man, human ADA expression generally was low in these transgenic mice, but high in the thymus, spleen and gastro-duodenal part of the gut. Apparently, all cis-regulatory elements essential for a human expression pattern were incorporated in the transgene and were functional in the murine background. Similarly to man, the upper alimentary tract of the transgenic mice revealed low human ADA activity in contrast to extremely high levels of murine ADA. The human gene probably lacks the cis-regulatory elements that target high level murine ADA expression to the murine upper alimentary tract. ADA-deficient mice rescued by introduction of the human ADA transgene appeared histologically and immunologically normal. Apparently, human ADA can complement murine ADA in all tissues, even in the epithelium of the upper alimentary tract where human ADA activity is as much as 70-fold lower than murine ADA activity in wild-type mice. Clearly, the lethal phenotype of ADA-deficient mice is due to the absence of ADA.

Adenosine Deaminase↗

PubMed1976

Competency-based education.

The essential elements of a P/CBDE program include the delineation of role-derived dietetic competencies, which are publicly stated in behavioral terms. The criteria used to measure the accomplishment of these competencies are criterion-referenced, and the student acquires the competencies at his own rate. Much confusion exists in differentiating between the essential characteristics and implementation modes. The use of modern technology and modular packaging of learning experiences does not automatically lead to a P/CBDE program. These are merely tools. The clear identification of competencies, objectives, and performance criteria are the essence of P/CBDE. Currently, dietetic educators are formulating competencies for their own programs. A national group of "experts" will need to be convened to develop competencies for the profession as a whole.

Clinical Competence↗

PubMed1992

Basic principles of immunology (immune response) for hemapheresis practitioners.

Advances in medical knowledge and technology have identified the essential elements involved in the human immune system, their relationships and interactions, and offer more advanced concepts in the design, function, and maintenance of immune response. Immune response begins with the earliest progenitor cell and transfers its legacy of protection through white blood cells and the complement system. A basic understanding of immunology is essential to the hemapheresis practitioner as new treatment regimens requiring hemapheresis interventions develop.

Antibody Formation↗

PubMed1999

Interactions at the NH2-terminal interface of cardiac troponin I modulate myofilament activation.

Cardiac troponin I (cTnI) is an essential element in activation of myofilaments by Ca2+ binding to cardiac troponin C (cTnC). Yet, its role in transduction of the Ca2+ binding signal to cardiac troponin T (cTnT) and tropomyosin-actin remain poorly understood. We have recently discovered that regions of cTnI C-terminal to a previously defined inhibitory peptide are essential for full inhibitory activity and Ca(2+)-sensitivity of cardiac myofilaments (Rarick et al., 1997). However, apart from its role in structural binding to cTnC, there is little knowledge concerning the role of the N-terminus of cTnI in the activation and regulation of cardiac myofilaments. To address this question, we generated wild-type mouse cardiac TnI (WT-cTnI; 211 residues) and two N-terminal deletion mutants of mouse cTnI, cTnI54-211 (missing 53 residues), and cTnI80-211 (missing 79 residues). The cTnI54-211 mutant retained the ability to bind to cTnT, but lost the ability to bind to cTnC, whereas the cTnI80-211 mutant lost the ability to bind to cTnT, but bound weakly to cTnC. Both mutants bound to F-actin. In the absence of Ca2+, cTnI54-211 was able to inhibit the unregulated MgATPase activity of myofibrils lacking endogenous cTnI-cTnC to the same extent as WT-cTnI, whereas cTnI80-211 had some impairment of its inhibitory capability. Reconstitution with cTnI54-211/cTnC complex did not restore Ca(2+)-activation of myofibrillar MgATPase activity at all, however, the cTnI80-211/cTnC complex restored Ca(2+)-activation to nearly 50% of that obtained with WT-cTnI/cTnC. These data provide the first evidence of a significant function of a cTnT-binding domain on cTnI. They also indicate that the structural cTnC binding site on cTnI is required for Ca(2+)-dependent activation of cardiac myofilaments, and that cTnT binding to the N-terminus of cTnI is a negative regulator of activation.

Actin Cytoskeleton↗

PubMed2004

Comparison of two monitoring systems for Cu and Mo in the Swedish environment.

Bio-geochemical samples (BGS) are roots of certain aquatic plants and mosses suitable for monitoring elements dissolved in stream water. The moose, a wild ruminant living in most parts of Sweden, represents higher trophic level and another manifestation of bioavailability. By analyzing BGS (n approximately 33600) and moose liver (n approximately 2400), a systematic survey has been performed in the terrestrial environment of Sweden. Cu and Mo are essential elements for life, and their presence is especially important for the Cu-dependent processes in ruminants. The availability of Cu and Mo as monitored in BGS and moose was visualized in the form of maps and subjected to further statistical analysis. The medians, with lower and upper quartiles indicated as intervals, for the country as a whole were: moose liver, Cu = 34 (20-59), Mo = 0.82 (0.58-1.06) mg kg(-1) wet weight; BGS, Cu = 50 (35-77), Mo = 9.0 (5.3-18.0) mg kg(-1) dry weight. The ranges of medians for the 22 Swedish counties were: moose liver, Cu = (20-62), Mo = (0.54-1.18) mg kg(-1) wet weight; BGS, Cu = (28-115), Mo = (5-47) mg kg(-1) dry weight. The relationships between the counties and the connections between the monitoring variables were elucidated by principal component analysis (PCA). It was demonstrated that two monitoring systems could give divergent results. An unexpectedly strong negative correlation was found between the county medians for Cu in BGS and moose liver. A possible explanation, based on the interaction between Cu and Mo in moose, could not be verified.

Animals↗

PubMed1999

Identification of cis-regulatory elements required for endosperm expression of the rice storage protein glutelin gene GluB-1.

Rice storage protein glutelin genes are coordinately regulated during seed development. A previous 5' deletion analysis using transgenic tobacco revealed that the minimum 5' region necessary for endosperm specificity was within -245 bp of the transcription start site, and included the AACA and GCN4 motifs that are highly conserved in the 5'-flanking regions of all glutelin genes. In this paper, the sequence elements essential for endosperm-specific expression are characterized in stable transgenic tobacco plants by both loss-of-function and gain-of-function experiments using this minimum promoter. Base substitution analysis shows that the proximal AACA motif between -73 and -61, and the GCN4 motif between -165 and -158 act as critical elements. An ACGT motif between -81 and -75, and Skn-I-like elements between -173 and -169 also play important roles in controlling the seed-specific expression. When the distal region between -245 and -145 containing the AACA and the GCN4 motifs or the proximal region between -113 and -46 containing the ACGT and AACA motifs is fused to a truncated promoter (-90 to +9) of the CaMV 35S gene fused to the beta-glucuronidase (GUS) reporter gene, high levels of seed-specific expression are observed in these fusions, thereby indicating that either pair of motifs is sufficient to confer seed expression in these fusions. However, when substituted for by the CaMV 35S core promoter (-46 to +1), seed expression is abolished, suggesting that the sequence between -90 and -46 of the CaMV 35S promoter containing G-box-like motif (as-1 element) is required for such specific expression in addition to AACA and GCN4 motifs. Therefore, we conclude that at least three cis-regulatory elements, the AACA motif, GCN4 motif and ACGT motif, are necessary to mediate endosperm expression of the GluB-1 glutelin gene.

Base Sequence↗

PubMed2004

Interaction of selenium compounds with zinc finger proteins involved in DNA repair.

As an essential element, selenium is present in enzymes from several families, including glutathione peroxidases, and is thought to exert anticarcinogenic properties. A remarkable feature of selenium consists of its ability to oxidize thiols under reducing conditions. Thus, one mode of action recently suggested is the oxidation of thiol groups of metallothionein, thereby providing zinc for essential reactions. However, tetrahedral zinc ion complexation to four thiolates, similar to that found in metallothionein, is present in one of the major classes of transcription factors and other so-called zinc finger proteins. Within this study we investigated the effect of selenium compounds on the activity of the formamidopyrimidine-DNA glycosylase (Fpg), a zinc finger protein involved in base excision repair, and on the DNA-binding capacity and integrity of xeroderma pigmentosum group A protein (XPA), a zinc finger protein essential for nucleotide excision repair. The reducible selenium compounds phenylseleninic acid, phenylselenyl chloride, selenocystine, ebselen, and 2-nitrophenylselenocyanate caused a concentration-dependent decrease of Fpg activity, while no inhibition was detected with fully reduced selenomethionine, methylselenocysteine or some sulfur-containing analogs. Furthermore, reducible selenium compounds interfered with XPA-DNA binding and released zinc from the zinc finger motif, XPAzf. Zinc release was even evident at high glutathione/oxidised glutathine ratios prevailing under cellular conditions. Finally, comparative studies with metallothionein and XPAzf revealed similar or even accelerated zinc release from XPAzf. Altogether, the results indicate that zinc finger motifs are highly reactive towards oxidizing selenium compounds. This could affect gene expression, DNA repair and, thus, genomic stability.

Animals↗

PubMed1985

Mineral X disease interactions.

The ability of animals to cope with infection may be influenced by mineral nutrition, in particular Mg and P of the macroelements and Zn, Fe, Cu and Se of the trace elements. Deficiencies of Zn, Fe, Cu and Se have resulted in a lowered resistance to disease either through an impaired immune response or faulty leukocyte function. The role of Se in bactericidal action of the phagocytes is associated with oxidative functions believed important for killing phagocytized bacteria. The role of these and other essential elements in disease prevention is an important area of animal nutrition research.

Anemia, Hypochromic↗

PubMed2002

When enough is enough: a conceptual basis for fair and defensible practice performance assessment.

INTRODUCTION: An essential element of practice performance assessment involves combining the results of various procedures in order to see the whole picture. This must be derived from both objective and subjective assessment, as well as a combination of quantitative and qualitative assessment procedures. Because of the severe consequences an assessment of practice performance may have, it is essential that the procedure is both defensible to the stakeholders and fair in that it distinguishes well between good performers and underperformers. LESSONS FROM COMPETENCE ASSESSMENT: Large samples of behaviour are always necessary because of the domain specificity of competence and performance. The test content is considerably more important in determining which competency is being measured than the test format, and it is important to recognise that the process of problem-solving process is more idiosyncratic than its outcome. It is advisable to add some structure to the assessment but to refrain from over-structuring, as this tends to trivialise the measurement. IMPLICATIONS FOR PRACTICE PERFORMANCE ASSESSMENT: A practice performance assessment should use multiple instruments. The reproducibility of subjective parts should not be increased by over-structuring, but by sampling through sources of bias. As many sources of bias may exist, sampling through all of them may not prove feasible. Therefore, a more project-orientated approach is suggested using a range of instruments. At various timepoints during any assessment with a particular instrument, questions should be raised as to whether the sampling is sufficient with respect to the quantity and quality of the observations, and whether the totality of assessments across instruments is sufficient to see 'the whole picture'. This policy is embedded within a larger organisational and health care context.

Clinical Competence↗

PubMed1984

Effect of the 21-bp repeat upstream element on in vitro transcription from the early and late SV40 promoters.

The role of the 21-bp repeat region [simian virus 40 (SV40) coordinates 40-103] on early and late SV40 promoter functions has been investigated in vitro using a variety of mutated templates. Using either a HeLa whole cell extract or a S100 extract, we analyzed the transcripts by quantitative S1 nuclease mapping. GC-rich motifs contained in the 21-bp direct repeat constituted an essential element for efficient early transcription in vitro in agreement with previous in vivo results. These GC-rich motifs act in a non-polar fashion, since inversion of the 21-bp region did not reduce early transcription. Some point mutations in the 22-bp imperfectly repeated sequence, that drastically reduce initiations from the early promoter in vivo, had little effect in vitro, indicating that all the functions of these GC-rich motifs cannot be reproduced in vitro at present. The requirement for the 21-bp repeat region was less stringent when the concentration of the early promoter sequence was increased, which suggests that its function may be to facilitate the recognition of the 'weak' SV40 early TATA box. The multiple late start sites were accurately used in vitro and the GC-rich motifs contained in the 21-bp repeat region were an important element for efficient in vitro initiation of transcription from the late promoter, irrespective of their orientation. However, the effect of the 21-bp repeat region on late initiations decreased strikingly with increasing distance to the start sites, although it was still detectable over a distance of 220 bp. Under the present in vitro conditions, the 72-bp repeat region stimulates weakly both early and late transcription.

Chromosome Deletion↗