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PubMed2004

[Acute STEMI in old and very old patients. The real life].

OBJECTIVES: From a prospective multicenter registry, we evaluated in three non-academic interventional cardiologic centers (Alsace/France), the coverage and the feasibility of the percutaneous coronary angioplasty (PTCA) in the acute phase of STEMI in the elderly (patients 75-years old and more). METHODS: We studied clinical characteristics and angiographic data of patients older than 75 years, and the PTCA results: the revascularisation rates and the intrahospital events were analysed. These data were compared with those of the younger patients and confronted with the literature data. RESULTS: Of a total of 1672 patients admitted for a STEMI, 342 (20.45%) were older than 75 years. These patients represented a high-risk group with a high proportion of women (50%), and many co-morbidities (e.g.: hypertension and diabetes mellitus), and three-vessel disease was found more often than in younger patients. Mortality rate was high in this subgroup and always more severe as compared to younger subjects, but remains variable according to the initial clinical profile. The global mortality was 20.47% but fell to 5.41% if we excluded the patients with cardiogenic shock, in Killip III and after resuscitation. PTCA is a coronary reperfusion technique particularly indicated in the management of the elderly presenting a STEMI. It is an effective technique in term of revascularisation, the reperfusion success (exclusively TIMI III flow) was indeed raised in the elderly even though it is lower than in younger patients (93.88 vs 97.18%). It is a quickly accessible technique, cath-lab accessibility provided, allowing a fast reperfusion and reducing hospitalization to a minimum. The management of the elderly presenting a STEMI has to focus on reducing the preadmission delay since this subgroup of patients hesitates to call the emergency (SMUR) when presenting an acute coronary symptomatology. The shorter the delay till admittance, the better the outcome. CONCLUSION: PTCA is a technique particularly indicated in the elderly in Alsace because of regional specificities: first of all geographic (proximity of the SMUR for virtually all the population of Alsace), and secondly the medical infrastructure since the strategy of exclusive primary PTCA is granted by numerous interventional cardiologic teams. In Alsace, the proportion of elderly patients (> or = 75 years) is going to increase significantly with a parallel rise of STEMI--"a frightening perspective". We have to take into account this evolution, this reperfusion technique presenting numerous advantages and very few complications.

Aged↗
PubMed2006

Olfactory shifts parallel superspecialism for toxic fruit in Drosophila melanogaster sibling, D. sechellia.

Olfaction in the fruit fly Drosophila melanogaster is increasingly understood, from ligand-receptor-neuron combinations to their axonal projection patterns into the antennal lobe . Drosophila thus offers an excellent opportunity to study the evolutionary and ecological dynamics of olfactory systems. We compared the structure and function of the generalist D. melanogaster with that of specialist D. sechellia, which oviposits exclusively on morinda fruit . Our analyses show that whereas the fruit's headspace was dominated by acids, antennae responded most strongly to hexanoates. D. sechellia exhibited an extraordinarily strong response to methyl hexanoate (MeHex). Behaviorally, D. sechellia was much more attracted to these morinda fruit volatiles than was D. melanogaster. The high sensitivity to MeHex was paralleled by a 2.5x-3 x overrepresentation of MeHex neurons on the antenna and a concordant 2.9 x increase in volume of the corresponding glomerulus as compared to D. melanogaster. In addition, the MeHex neuron exhibited an extreme sensitivity down to femtograms of its ligand. In contrast, no peripherally mediated shift was found paralleling D. sechellia's increased attraction to acids. These findings are a demonstration of evolution acting at several levels in the olfactory circuitry in mediating a fruit fly's unique preference for fruit toxic to its sibling species .

Adaptation, Physiological↗
PubMed2005

Is low mood an adaptation? Evidence for subtypes with symptoms that match precipitants.

BACKGROUND: Although severe depression is dysfunctional, the capacity to experience normal low mood may be useful in certain fitness-threatening situations. Moreover, if specific kinds of situations recurred often enough in the course of evolution, natural selection may have shaped partially differentiated subtypes of low mood that are parallel to the subtypes of anxiety that protect against different kinds of danger. To test this hypothesis, we examined how symptoms of low mood differ depending upon the precipitating situation, and whether these differences match expectations of symptoms useful in each kind of situation. METHOD: 337 subjects who experienced a period of low mood within the last year wrote accounts describing perceived causes of their low mood and they filled out the CES-D depression inventory. Seven symptom scales were derived from analysis of CES-D data. Independent judges blindly coded the accounts into one of six precipitant categories. RESULTS: Different untoward situations were associated with different symptoms that were predicted to be useful in those situations. Social losses (death of a loved one, romantic breakups, and social isolation) were associated with greater crying and arousal. Failure to reach a goal, stress, and winter seasons were associated with more fatigue and pessimism. DISCUSSION: These results suggest that natural selection shaped not only a generic state of low mood but also partially differentiated subtypes shaped to cope with specific situations that were associated with fitness losses among our ancestors.

Adaptation, Psychological↗
PubMed1997

Dual-color fluorescence cross-correlation spectroscopy for multicomponent diffusional analysis in solution.

The present paper describes a new experimental scheme for following diffusion and chemical reaction systems of fluorescently labeled molecules in the nanomolar concentration range by fluorescence correlation analysis. In the dual-color fluorescence cross-correlation spectroscopy provided here, the concentration and diffusion characteristics of two fluorescent species in solution as well as their reaction product can be followed in parallel. By using two differently labeled reaction partners, the selectivity to investigate the temporal evolution of reaction product is significantly increased compared to ordinary one-color fluorescence autocorrelation systems. Here we develop the theoretical and experimental basis for carrying out measurements in a confocal dual-beam fluorescence correlation spectroscopy setup and discuss conditions that are favorable for cross-correlation analysis. The measurement principle is explained for carrying out DNA-DNA renaturation kinetics with two differently labeled complementary strands. The concentration of the reaction product can be directly determined from the cross-correlation amplitude.

DNA↗
PubMed1999

The human homologue of Caenorhabditis elegans CED-6 specifically promotes phagocytosis of apoptotic cells.

A key feature of the process of programmed cell death (apoptosis) is the efficiency with which the dying cells are recognized and engulfed by phagocytes [1]. Apoptotic cells are rapidly cleared either by neighbouring cells acting as semi-professional phagocytes or by experts of the macrophage line, so that an inflammatory response is avoided [2]. The Caenorhabditis elegans gene ced-6 is required for efficient engulfment of apoptotic cells [3] and is one of a group of genes that define two partially redundant parallel pathways for the engulfment process [4] [5]. These pathways may be conserved across evolution, as two other engulfment genes have human homologues. A CED-5 homologue is part of a human CrkII-DOCK180-Rac signaling pathway proposed to mediate cytoskeletal reorganization [6] [7] [8] and a CED-7 homologue is similar to the ABC transporters [9] [10]. Here, we report the cloning and characterization of human CED-6, a human homologue of C. elegans CED-6. The 34 kDa hCED-6 protein is expressed in most tissues, some human cancer cells, and in primary human macrophages. We developed an assay that quantitates the phagocytic activity of mammalian macrophages: the number of apoptotic cells that have been internalized is measured by the uptake of lacZ-positive apoptotic cells by adherent transgenic macrophages. The results of this assay demonstrate that overexpression of hCED-6 promotes phagocytosis only of apoptotic cells and suggest that hCED-6 is the mammalian orthologue of C. elegans CED-6 and is a part of a highly conserved pathway that specifically mediates the phagocytosis of apoptotic cells.

Animals↗
PubMed2005

New aspects of the electroadsorption of ethyl xanthate on copper electrodes.

The interaction of the ethyl xanthate (EX) anion with a copper electrode in a borate buffer solution, pH 9.2, has been investigated by cyclic voltammetry (CV), electrochemical quartz crystal microbalance (EQCM), electrochemical impedance spectroscopy (EIS), and measurements of contact angle (CA) under controlled potential. The results obtained allow establishing that, in the potential range from -0.80 and -0.60 V, two parallel reactions were characterized. These reactions were the ethyl xanthate electroadsorption and the hydrogen evolution reaction (HER). This last reaction has not been described by previous authors. Besides, the EIS measurements show that the mechanism of the HER on copper electrodes is not affected by the presence of a ethyl xanthate species. The EQCM study shows that in the electrodesorption process the departure of each ethyl xanthate species from the copper electrode is accompanied with the simultaneous entry of four to five water molecules. This fact is in accordance with the number of copper atoms involved in the adsorption of one ethyl xanthate species.

Journal Article↗
PubMed2004

Retinoic acid influences anteroposterior positioning of epidermal sensory neurons and their gene expression in a developing chordate (amphioxus).

In developing chordates, retinoic acid (RA) signaling patterns the rostrocaudal body axis globally and affects gene expression locally in some differentiating cell populations. Here we focus on development of epidermal sensory neurons in an invertebrate chordate (amphioxus) to determine how RA signaling influences their rostrocaudal distribution and gene expression (for AmphiCoe, a neural precursor gene; for amphioxus islet and AmphiERR, two neural differentiation genes; and for AmphiHox1, -3, -4, and -6). Treatments with RA or an RA antagonist (BMS009) shift the distribution of developing epidermal neurons anteriorly or posteriorly, respectively. These treatments also affect gene expression patterns in the epidermal neurons, suggesting that RA levels may influence specification of neuronal subtypes. Although colinear expression of Hox genes is well known for the amphioxus central nervous system, we find an unexpected comparable colinearity for AmphiHox1, -3, -4, and -6 in the developing epidermis; moreover, RA levels affect the anteroposterior extent of these Hox expression domains, suggesting that RA signaling controls a colinear Hox code for anteroposterior patterning of the amphioxus epidermis. Thus, in amphioxus, the developing peripheral nervous system appears to be structured by mechanisms parallel to those that structure the central nervous system. One can speculate that, during evolution, an ancestral deuterostome that structured its panepidermal nervous system with an RA-influenced Hox code gave rise to chordates in which this patterning mechanism persisted within the epidermal elements of the peripheral nervous system and was transferred to the neuroectoderm as the central nervous system condensed dorsally.

Animals↗
PubMed1988

Antiviral agents targeted to interact with viral capsid proteins and a possible application to human immunodeficiency virus.

The tertiary structure of most icosahedral viral capsid proteins consists of an eight-stranded antiparallel beta-barrel with a hydrophobic interior. In a group of picornaviruses, this hydrophobic pocket can be filled by suitable organic molecules, which thereby stop viral uncoating after attachment and penetration into the host cell. The antiviral activity of these agents is probably due to increased rigidity of the capsid protein, which inhibits disassembly. The hydrophobic pocket may be an essential functional component of the protein and, therefore, may have been conserved in the evolution of many viruses from a common precursor. Since eight-stranded anti-parallel beta-barrels, with a topology as in viral capsid proteins, are not generally found for other proteins involved in cell metabolism, this class of antiviral agents is likely to be more virus-specific and less cytotoxic. Furthermore, the greatest conservation of viral capsid proteins occurs within this pocket, whereas the least conserved part is the antigenic exterior. Thus, compounds that bind to such a pocket are likely to be effective against a broader group of serologically distinct viruses. Discovery of antiviral agents of this type will, therefore, depend on designing compounds that can enter and fit snugly into the hydrophobic pocket of a particular viral capsid protein. The major capsid protein, p24, of human immunodeficiency virus would be a likely suitable target.

Antiviral Agents↗
PubMed2000

Phylogenetic analysis of GBV-C/hepatitis G virus.

Comparison of 33 epidemiologically distinct GBV-C/hepatitis G virus complete genome sequences suggests the existence of four major phylogenetic groupings that are equally divergent from the chimpanzee isolate GBV-C(tro) and have distinct geographical distributions. These four groupings are not consistently reproduced by analysis of the virus 5'-noncoding region (5'-NCR), or of individual genes or subgenomic fragments with the exception of the E2 gene as a whole or of 200-600 nucleotide fragments from its 3' half. This region is upstream of a proposed anti-sense reading frame and contains conserved potential RNA secondary structures that may be capable of directing the internal initiation of translation. Phylogenetic analysis of this region from certain South African isolates is consistent with previous analysis of the 5'-NCR suggesting that these belong to a fifth group. The geographical distribution of virus variants is consistent with a long evolutionary history that may parallel that of pre-historic human migrations, implying that the long-term evolution of this RNA virus is extremely slow.

5' Untranslated Regions↗
PubMed2003

Mixed myelodysplastic syndrome and myeloproliferative disorder with bone marrow and pulmonary fibrosis: the role of megakaryocytes.

The case of an 80-year-old woman displaying myelodysplastic syndrome evolving into a myeloproliferative disorder with myelofibrosis and pulmonary fibrosis, is reported. This case is characterized by an initial presentation of a myelodysplastic syndrome with normal karyotype and moderate fibrosis, its evolution towards a myeloproliferative disorder with myelofibrosis and the worsening of pulmonary fibrosis in parallel to the acceleration of the myeloproliferative disorder and myelofibrosis. These features and the high concentration of plasma platelet factor-4 suggest a role of megakaryocyte/platelet degranulation in the development of fibrosis.

Aged↗
PubMed2004

A dissociation of motion and spatial-pattern vision in the avian telencephalon: implications for the evolution of "visual streams".

The ectostriatum is a large visual structure in the avian telencephalon. Part of the tectofugal pathway, the ectostriatum receives a large ascending thalamic input from the nucleus rotundus, the homolog of the mammalian pulvinar complex. We investigated the effects of bilateral lesions of the ectostriatum in pigeons on visual motion and spatial-pattern perception tasks. To test motion perception, we measured performance on a task requiring detection of coherently moving random dots embedded in dynamic noise. To test spatial-pattern perception, we measured performance on the detection of a square wave grating embedded in static noise. A double dissociation was revealed. Pigeons with lesions to the caudal ectostriatum showed a performance deficit on the motion task but not the grating task. In contrast, pigeons with lesions to the rostral ectostriatum showed a performance deficit on the grating task but not the motion task. Thus, in the avian telencephalon, there is a separation of visual motion and spatial-pattern perception as there is in the mammalian telencephalon. However, this separation of function is in the targets of the tectofugal pathway in pigeons rather than in the thalamofugal pathway as described in mammals. The implications of these findings with respect to the evolution of the visual system are discussed. Specifically, we suggest that the principle of parallel visual streams originated in the tectofugal pathway rather than the thalamofugal pathway.

Analysis of Variance↗
PubMed1977

Changes in Cuban health care: an argument against technological pessimism.

Since the popular revolution in 1959, alterations in the organization and delivery of health care in Cuba have paralleled the country's broader political, economic, and social changes. This paper discusses the evolution of the Cuban health care system during the past seventeen years within the wider context of societal development. The authors compare three "snapshots" of Cuba, the first in 1959, the second in 1970, and the last in 1976, and touch upon such issues as the organization of health care delivery, the recruitment and socialization of health workers, and aspects of the process of receiving health care. They point out that the Cuban experience should be of particular interest to the developing world. For though it is true that a larger portion of Cuban national resources has been directed to the health and social services than in other developing countries, nonetheless, it was largely through the reorganization and equalization of the prerevolutionary health care system that improvement in the health status of the population was achieved. It appears that Cuba could well serve as an example for those who are skeptical about the possibility of combining technical development with improvement in the humane quality of care.

Cuba↗
PubMedDate not supplied

History of pediatric oncology.

Pediatric oncology emerged as a subspeciality in the United States of America following the observations in 1948 of Farber and his associates of the benefits of chemotherapy for acute leukemia. The establishment of national cooperative chemotherapy groups furthered its development. More recently, the subspeciality has been recognized by the American Board of Pediatrics. Even more recently, training programs for the subspecialty have been given accreditation. Parallel to development of the specialty in the United States has been a similar evolution of pediatric oncology in Europe.

Antineoplastic Agents↗
PubMed2001

Architecture of the sperm cell of Psilotum.

In this correlated SEM (scanning electron microscope) and TEM (transmission electron microscope) investigation, we describe architectural details of the multiflagellated sperm cell of Psilotum nudum. Comparisons with other pteridophytes are made to (1) assess the placement of Psilotum among pteridophyte taxa and (2) evaluate structural modifications of sperm cells during land plant evolution. The released spermatozoid of Psilotum coils 2.0 revolutions and is outlined by a parallel band of up to 190 microtubules. The elongated nucleus is highly compacted and parallels the cellular coils with numerous mitochondria and starch-laden plastids distributed along its length. Along the anterior coil is an elaborate locomotory apparatus that includes ∼36 flagella that are inserted into the cell by basal bodies. Subtending the basal bodies is the multilayered structure, which consists of a long narrow lamellar strip and an overlying band of microtubules. An elongated anterior mitochondrion underlies the multilayered structure. Additional amyloplasts and mitochondria are aggregated along the anterior coil in association with the locomotory apparatus, while a fibrous band encircles the leading edge of the cell. Salient features of this cell, including details of the locomotory apparatus, structure and position of organelles, and arrangement of the spline, are shared by spermatozoids of Equisetum and ferns (including eusporangiate and leptosporangiate taxa). Thus, this study provides morphological support for the hypothesis that Psilotum nudum is a member of an assemblage that includes ferns and Equisetum. However, the less streamlined architecture of Psilotum gametes and the lack of architectural features shared with any specific taxon examined to date suggest that Psilotum is an early divergent fern, with relatively remote affinities to Ophioglossaceae and Equisetaceae.

Journal Article↗
PubMed2002

Differential gene expression analysis in a rabbit model of osteoarthritis induced by anterior cruciate ligament (ACL) section.

Osteoarthritis (OA) is the most common of all joint diseases to affect mankind and is characterized by the degradation of articular cartilage. The low availability of normal and pathologic human cartilage and the inability to study the early stages of the disease in humans has led to the development of numerous animal models of OA. The aim of our study was to establish gene expression profiles during the progression of a rabbit model of OA induced by anterior cruciate ligament (ACL) section. Semiquantitative RT-PCR was used to follow expression of several relevant molecules (type II and X collagens, aggrecan, osteonectin, betaig-h3, BiP, TIMP-1, MMP-1, -3, -13, aggrecanase-1, -2) during development of OA in articular cartilage. In parallel, we monitored the activities of collagenase, caseinase, phospholipase A2 and glycosyltransferases (xylosyl-, galactosyl-, glucuronyl- and N-acetyl-galactosaminyl-transferase). Novel cDNA clones for rabbit type X collagen, aggrecanase-1 and -2, osteonectin and BiP were constructed to obtain species-specific primers. Ours result show that MMP-13 (collagenase-3) gene expression increased dramatically early after ACL surgery and remained high thereafter. An increase in MMP-1 (collagenase-1) and MMP-3 expression was also noted with an absence of variation for TIMP-1 expression. In addition, the global MMPs activities paralleled the MMP gene expression. These data together characterize at the molecular level the evolution of OA in this rabbit model. Furthermore, we have undertaken a search for identifying differentially expressed genes in normal and OA cartilage in this model, by differential display RT-PCR. We present here preliminary results with the determination of the best technical conditions to obtain reproducible electrophoresis patterns of differential display RT-PCR.

Aggrecans↗
PubMed1991

The clinical differential diagnosis of dementia: concept and methodology.

Dementia is a rather heterogeneous syndrome. This heterogeneity is expressed in the diversity of its clinical characteristics and its evolution and in the underlying etiologic factors. Unfortunately, these divisions do not run in parallel. Therefore, considerable diversity exists in the manifestations of each pathologic entity, thus making a clinical diagnosis of dementia type an educated guess at best. The need for biologic markers of the various entities is stressed in this article.

Alzheimer Disease↗
PubMed1986

Identification and its vicissitudes, as observed in the neuroses.

This paper is an attempt to catalogue the different modes of identification which become manifest in the interaction between analyst and analysand. To this end the author employs a frame of reference suggested by the Kleinian concept of projective identification, focusing particularly on the integration of the projective and introjective moments of the identification with the communications circuit linking the self and the internal and external objects. Clinical material from two cases illustrates the vicissitudes of the processes of internalization and externalization as well as their different identificatory outcomes. The predominant quality of the identification in neuroses is differentiated from the characteristics observed in psychotic states. Finally the quality of identification is assessed in the context of symbolic function quality. A parallel is drawn between the progressive and regressive movements in identification processes, and the evolution or involution of symbol structure.

Adult↗
PubMed1980

[Food consumption in relation to size of collectivity. Parallel time trends (author's transl)].

The consumption of the French with respect to the size of parishes and its evolution from 1965 to 1974 can be investigated, thanks to the survey of Institut National de la Statistique et des Etudes Economiques on food consumption of a representative sample of households. During this period, with regard to the growing size of parishes and with respect to time, the percentage of lipidic calories has been raising, chiefly from the decrease in the consumption of vegetable foods which carries with it, at the same time, a decrease of the intake of glucids, dietary fibers and of the total energy intake. The shortcomings of data collecting explain only a small part of the discrepancies observed.

Diet↗