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PubMed1999

[Medical data in pathology--evaluation of a large collection. (530,000 diagnoses coded in SNOMED II)].

The paper is describing the design and the performance of the computerized system, from its introduction in 1982 until the present day. The first device, using the MUMPS language on a mini-computer, followed by a VAX computer with terminals have been replaced in 1996 by an application program, using ORACLE, based on the client-server concept. The content and the particularities of the different data groups are discussed, concerning the functional components of the data bank: 'PATIENTS', 'SPECIMEN', 'SENDERS', 'REPORT' and 'DIAGNOSES'. By means of examples, we demonstrate the chronological evolution of the registration of persons, the distribution of the diagnoses according to the organ systems, the possibilities to combine various lesions and an algorithm to assure that a given lesion is registered only once per patient. In first place, the efficiency and the reliability of manual coding by a pathologist using the Systematized Nomenclature of Medicine (SNOMED; 2nd edition [1979/1982]) is discussed. The data bank currently contains 530,000 diagnoses, distributed among on SNOMED's five main modules, obtained from 1500 autopsies, 140,000 surgical and 180,000 cytological specimens. Concluding the article, an analysis is made of desirable developments in the future with the aim of a better integration of the acquired information in routine work and an enhanced use of the medical content for epidemiological research or statistical analysis.

Abstracting and Indexing↗

PubMed2003

[Preneoplastic anal lesions and anal canal carcinoma].

Anal canal cancer rate is relatively high among HIV-positive patients, particularly in homosexual men, where it is twice that of HIV-negative homosexual men. As for uterine cervix cancer, it is possible that anal canal cancer is linked to human papillomaviruses (HPV): in fact, its oncogenic serotypes are found in 60% of tumours. Most of anal mucosa in HIV-positive patients is infected by HPV. It causes Anal Squamous Intraepithelial Lesions (ASTI): low grade and high grade squamous intraepithelial lesions, which can probably progress to invasive anal cancer. In the anal mucosa, HPV induces clinically flat condylomata. They generally are invisible and revealed only by acetic acid application. Sixty percent of seropositive gay men and 26% of seropositive women have anal ASTI. This rate is higher than in the general population. A decreasing of systemic and local immunity and so probable interactions between HPV and HIV could explain the frequency of anal ASTI among seropositive patients. Introduction of highly active antiretroviral therapy does not really influence the evolution of anal dysplasia. Screening of preneoplastic lesion is possible with anal Pap smear, and when it is positive, patients must undergo high resolution anuscopy. Cost effectiveness analyses indicate that only the highest risk group (HIV-positive gay men) should have anal screening. Only high grade squamous intraepithelial lesions have to he systematically treated, low grade squamous intraepithelial lesions could he simply followed up. The best treatment of anal dysplasia is surgical excision, with careful follow-up, because of high recurrence rate among seropositive patients.

Anal Canal↗

PubMedDate not supplied

[Endocrinological aspects of acquired immunodeficiency syndrome (AIDS)].

The acquired immunodeficiency syndrome (AIDS) is a severe disease. Lung, brain and digestive complaints that result in opportunistic infections and neoplasms are the most documented. The endocrine disorders, the description of which is recent on the basis of post-mortem data, motivated some authors to undertake studies in order to evaluate endocrine function in patients infected with human immunodeficiency virus (HIV). An increase in serum cortisol level due to stress adaptation in the early stage of the disease is reported, whereas peripheral adrenal insufficiency, although unusual, appears in the late stage. Hypogonadism is common in men with HIV infection but its origin is discussed, central or peripheral. The thyroid function is generally preserved, but low T3 syndrome which correlates with bad prognosis may be observed. Anterior hypopituitarism, which is rare, hyponatremia more frequent because of its etiopathogenic factors in AIDS, constant and precocious hyperprolactinemia, are noticed. The episodes of asymptomatic or severe hypoglycemia may be explained by inanition and side effects of drugs. The non-specificity of the clinical manifestations of endocrine dysfunction masked by the classic signs of AIDS, shouldn't make forget the systematic search of glandular abnormalities as soon as an evocative symptomatology is conspicuous. The mechanisms of endocrine complications are badly known, but opportunistic infections, drugs, particularities related to the structure of HIV and interleukin 1 (IL1) surely play a role. The recognition of endocrine disorders is essential for optimal therapy because, unknown, their evolution is dramatic.

Acquired Immunodeficiency Syndrome↗

PubMedDate not supplied

[Menetrier's disease and edematous syndrome (author's transl)].

The authors report a case of Menetrier's disease revealed in a 51 years woman before oedomas by systematic gastroscopy. Somes particularities of this case authorize to argue problems put by this disease: a thyroid nodule treated by L + triodothyronin; an eosinophilia; a biological study of gastric secretion, gastrin and intrinsec factor level; an hormonal, immunologic and genetic exploration; an histochimic and ultra-structural study of operative portion; its favorable evolution after total gastrectomy.

Edema↗

PubMed1993

Mixed anxiety depression. For and against.

The subject of mixed anxiety depression has been the topic of a somewhat confused discussion. At one point, it was held that anxiety and depression were both manifestations of an underlying affective disorder, but systematic work by Martin Roth and others clearly demonstrated that anxiety disorders could be separated from depressive disorders via a multivariate scale. Interestingly, spontaneous panic attacks were among the highest loading items on this scale. Nonetheless, it was plain that many patients were simultaneously anxious and depressed. Interest then grew in understanding the evolution of these syndromes over time. In general, anxiety syndromes antecede depressive syndromes, although there are many exceptions. For instance, some people only develop panic attacks when in the midst of a depressive episode. To attempt to understand these complexities, detailed family studies have been attempted with often contradictory results. We shall present family study data indicating that patients with comorbid panic disorder and depression have different familial patterns from those with panic disorder alone. In addition, a practical question is whether there exist patients, primarily in private settings, who present with symptoms of anxiety and depression but do not meet full criteria for any of the currently defined syndromes. Such patients are often referred to as subsyndromal or subthreshold patients. Epidemiological data indicates that such patients exist and that their symptomatology is associated with social and functional impairment. Recently the DSM IV field trial has specifically addressed this issue by clinical investigations of primary care and psychiatric facilities. These results will be reported.

Anxiety Disorders↗

PubMed2002

Molecular systematics of the Jacks (Perciformes: Carangidae) based on mitochondrial cytochrome b sequences using parsimony, likelihood, and Bayesian approaches.

The Carangidae represent a diverse family of marine fishes that include both ecologically and economically important species. Currently, there are four recognized tribes within the family, but phylogenetic relationships among them based on morphology are not resolved. In addition, the tribe Carangini contains species with a variety of body forms and no study has tried to interpret the evolution of this diversity. We used DNA sequences from the mitochondrial cytochrome b gene to reconstruct the phylogenetic history of 50 species from each of the four tribes of Carangidae and four carangoid outgroup taxa. We found support for the monophyly of three tribes within the Carangidae (Carangini, Naucratini, and Trachinotini); however, monophyly of the fourth tribe (Scomberoidini) remains questionable. A sister group relationship between the Carangini and the Naucratini is well supported. This clade is apparently sister to the Trachinotini plus Scomberoidini but there is uncertain support for this relationship. Additionally, we examined the evolution of body form within the tribe Carangini and determined that each of the predominant clades has a distinct evolutionary trend in body form. We tested three methods of phylogenetic inference, parsimony, maximum-likelihood, and Bayesian inference. Whereas the three analyses produced largely congruent hypotheses, they differed in several important relationships. Maximum-likelihood and Bayesian methods produced hypotheses with higher support values for deep branches. The Bayesian analysis was computationally much faster and yet produced phylogenetic hypotheses that were very similar to those of the maximum-likelihood analysis.

Animals↗

PubMed2006

Highly conserved syntenic blocks at the vertebrate Hox loci and conserved regulatory elements within and outside Hox gene clusters.

Hox genes in vertebrates are clustered, and the organization of the clusters has been highly conserved during evolution. The conservation of Hox clusters has been attributed to enhancers located within and outside the Hox clusters that are essential for the coordinated "temporal" and "spatial" expression patterns of Hox genes in developing embryos. To identify evolutionarily conserved regulatory elements within and outside the Hox clusters, we obtained contiguous sequences for the conserved syntenic blocks from the seven Hox loci in fugu and carried out a systematic search for conserved noncoding sequences (CNS) in the human, mouse, and fugu Hox loci. Our analysis has uncovered unusually large conserved syntenic blocks at the HoxA and HoxD loci. The conserved syntenic blocks at the human and mouse HoxA and HoxD loci span 5.4 Mb and 4 Mb and contain 21 and 19 genes, respectively. The corresponding regions in fugu are 16- and 12-fold smaller. A large number of CNS was identified within the Hox clusters and outside the Hox clusters spread over large regions. The CNS include previously characterized enhancers and overlap with the 5' global control regions of HoxA and HoxD clusters. Most of the CNS are likely to be control regions involved in the regulation of Hox and other genes in these loci. We propose that the regulatory elements spread across large regions on either side of Hox clusters are a major evolutionary constraint that has maintained the exceptionally long syntenic blocks at the HoxA and HoxD loci.

Animals↗

PubMed2005

The flexible evolutionary anchorage-dependent Pardee's restriction point of mammalian cells: how its deregulation may lead to cancer.

Living cells oscillate between the two states of quiescence and division that stand poles apart in terms of energy requirements, macromolecular composition and structural organization and in which they fulfill dichotomous activities. Division is a highly dynamic and energy-consuming process that needs be carefully orchestrated to ensure the faithful transmission of the mother genotype to daughter cells. Quiescence is a low-energy state in which a cell may still have to struggle hard to maintain its homeostasis in the face of adversity while waiting sometimes for long periods before finding a propitious niche to reproduce. Thus, the perpetuation of single cells rests upon their ability to elaborate robust quiescent and dividing states. This led yeast and mammalian cells to evolve rigorous Start [L.H. Hartwell, J. Culotti, J. Pringle, B.J. Reid, Genetic control of the cell division cycle in yeast, Science 183 (1974) 46-51] and restriction (R) points [A.B. Pardee, A restriction point for control of normal animal cell proliferation, Proc. Natl. Acad. Sci. U. S. A. 71 (1974) 1286-1290], respectively, that reduce deadly interferences between the two states by enforcing their temporal insulation though still enabling a rapid transition from one to the other upon an unpredictable change in their environment. The constitutive cells of multi-celled organisms are extremely sensitive in addition to the nature of their adhering support that fluctuates depending on developmental stage and tissue specificity. Metazoan evolution has entailed, therefore, the need for exceedingly flexible anchorage-dependent R points empowered to assist cells in switching between quiescence and division at various times, places and conditions in the same organism. Programmed cell death may have evolved concurrently in specific contexts unfit for the operation of a stringent R point that increase the risk of deadly interferences between the two states (as it happens notably during development). But, because of their innate flexibility, anchorage-dependent R points have also the ability to readily adjust to a changing structural context so as to give mutated cells a chance to reproduce, thereby encouraging tumor genesis. The Rb and p53 proteins, which are regulated by the two products of the Ink4a-Arf locus [C.J. Sherr, The INK4a/ARF network in tumor suppression, Nat. Rev., Mol. Cell Biol. 2 (2001) 731-737], govern separable though interconnected pathways that cooperate to restrain cyclin D- and cyclin E-dependent kinases from precipitating untimely R point transit. The expression levels of the Ink4a and Arf proteins are especially sensitive to changes in cellular shape and adhesion that entirely remodel at the time when cells shift between quiescence and division. The Arf proteins further display an extremely high translational sensitivity and can activate the p53 pathway to delay R point transit, but, only when released from the nucleolus, 'an organelle formed by the act of building a ribosome' [T. Mélèse, Z. Xue, The nucleolus: an organelle formed by the act of building a ribosome, Curr. Opin. Cell Biol. 7 (1995) 319-324]. In this way, the Ink4a/Rb and Arf/p53 pathways emerge as key regulators of anchorage-dependent R point transit in mammalian cells and their deregulation is, indeed, a rule in human cancers. Thus, by selecting the nucleolus to mitigate cell cycle control by the Arf proteins, mammalian cells succeeded in forging a highly flexible R point enabling them to match cell division with a growth rate imposed by factors controlling nucleolar assembling, such as nutrients and adhesion. It is noteworthy that nutrient control of critical size at Start in budding yeast has been shown recently to be governed by a nucleolar protein interaction network [P. Jorgensen, J.L. Nishikawa, B.-J. Breitkreutz, M. Tyers, Systematic identification of pathways that couple cell growth and division in yeast, Science 297 (2002) 395-400].

ADP-Ribosylation Factors↗

PubMed1992

The origin and evolution of activity analysis.

Practitioners of occupational therapy in the early 1900s selected therapeutic activities with an intuitive understanding of their characteristics and operations. The term activity analysis and the methodology for breaking down and examining tasks scientifically, however, were borrowed from industry during World War I. Methods originally used in time and motion study of jobs were applied to vocational retraining and therapeutic crafts; later, they were applied to a broader range of activities. The most systematic early use of activity analysis was in occupational therapy for physical dysfunction, particularly in military hospitals. Development of the concept was gradual until the 1970s, when the delineation of theoretical frames of reference for practice led to important changes. Today, activity analysis is viewed as a multifaceted process that involves both generic and specific components.

Ergonomics↗

PubMed2004

Application of proteomics in phylogenetic and evolutionary studies.

There are few papers that deal specifically with evolutionary studies and proteomics. However, applying proteomics to these studies promises to open new perspectives apropos the construction of phylogenetic trees and the detection of evolutionary changes. Principles and methods of phylogenetic systematics could be used to compare and evaluate proteomes. This would permit the detection and characterization of specific proteins that have evolutionary value in defining monophyly, paraphyly, and polyphyly.

Algorithms↗

PubMed1996

Chemical-Shift-Selective Acquisition of Multiple-Quantum-Filtered 23Na Signal

Equations describing the multiple-quantum (MQ) signal produced by an MQ pulse sequence are systematically derived in both absence and presence of refocusing RF pulses. When the RF pulses in an MQ pulse sequence satisfy certain conditions, these equations may be arranged in a factorized form. The off-resonance effects on the MQ signal due to chemical shift can then be analyzed separately during the preparation and evolution times. Using the reformulated equations, the dependence of the amplitude of an MQ signal on the phase shift induced by the resonance offset during the preparation and evolution times is demonstrated. By use of the new equations, it is shown that the off-resonance effects, occurring during both the preparation and evolution times, may be described in terms of the same physical process, i.e., interference between echo and antiecho. In applying the off-resonance effects for the elimination of the MQ signal in the presence of chemical shift, it is possible to suppress the MQ signal over a wider off-resonance bandwidth by use of the nonrefocused preparation and evolution times than by use of a single time. Furthermore, by taking an alternative approach in deriving the equations, the interference between echo and antiecho due to the resonance offset is shown to be insensitive to the flip angle of the creation RF pulse (usually the second pi/2 RF pulse). The theoretical findings were experimentally verified by use of a phantom containing sodium in agarose.

Journal Article↗

PubMed1975

Symmetries of genetic code-doublets.

The fact that 64 base triplets code only about 20 essential amino acids implies a strong degeneracy of certain base doublets. It is shown that the set of degenerate base doublets and the set of non-degenerate base doublets are highlly structured. A mathematical formalism is introduced which allows a systematic description of the consequences of an exchange of bases in a doublet. By this formalism it is shown that the two mentioned set have in fact the same structure.

Biological Evolution↗

PubMed2001

Calculation of radiation-induced DNA damage from photons and tritium beta-particles. Part I: Model formulation and basic results.

Radiation-induced damage in nucleosomal DNA was modelled by Monte Carlo means. An atomistic representation of DNA with a first hydration shell was used. DNA single- and double-strand break (SSB and DSB) yields were calculated for 137Cs photons, x-rays and tritium beta-particles. Monte Carlo-generated electron tracks for liquid water were used to model energy deposition. Chemical evolution of a track and interactions between species and DNA following water radiolysis were modelled in an encounter-controlled manner. The effects of varying the scavenging capacity of the environment, the extent of DNA protection by histones and the setting of a threshold for direct energy depositions on DNA break yields were all systematically studied. DSB complexity was assessed in terms of DNA breaks and base damage accompanying a DSB. Model parameters were adjusted to make predictions consistent with experimental data on DSB yields and yield modification by a variety of factors including changing DNA conformation and incorporation of scavengers. An embedded model of nucleosomal DNA by histones was required to explain experimentally observed modification of DSB yield by removal of bound histones. Complex DSB, defined as DSB accompanied by an additional strand breakage, exhibited high association with base damage. It is shown that hydroxyl radical interactions with bases are a major contributor to DSB complexity. On average there were 1.15 and 2.69 OH-base interactions accompanying simple and complex DSB, respectively for 137Cs. Over 80% of complex DSB had at least one OH-base interaction associated with a DNA break.

Beta Particles↗

PubMed2006

[Recurrence of hepatitis C virus (HCV) infection after liver transplantation for HCV-related disease: host factors and viral factors implicated in the occurrence and the severity of HCV recurrence].

Cirrhosis due to chronic infection by hepatitis C virus (HCV), associated or not to a primary hepatocarcinoma, has become the first indication of liver transplantation. Graft reinfection by HCV is considered to be systematic while its prognosis is variable from one patient to another. A better knowledge of factors implicated in the occurrence and severity of hepatitis C recurrence is crucial in order to make optimal patients' monitoring. This article aims to present available data in this field, clarifying the role of viral factors (viral load, genotype, evolution of viral quasispecies) and host-related factors (immune response) which could take part in the development of hepatitis C recurrence.

Carcinoma, Hepatocellular↗

PubMed1995

Origins of amino acids in the early solar system.

Synthesis of meteoritic amino acids probably took place in the aqueous sub-surface regions of one or more asteroid-sized parent bodies. Starting material for those reactions apparently consisted of a population of more simple compounds including a suite of aliphatic precursors characterised by (1) complete structural diversity, (2) prevalence of branched- over straight-chain species, (3) exponential decrease in abundance with increasing C number, (4) large enrichment in D, and, probably, (5) systematic decrease in 13C/12C with increasing C number. Those properties were apparently acquired during synthesis of the precursors by ion-molecule reactions in a presolar molecular cloud.

Amino Acids↗

PubMed2002

[Optic pathway gliomas in neurofibromatosis type I. Longitudinal study of 30 cases in two multidisciplinary practices].

UNLABELLED: The aim of this study was to analyse the outcome of optic pathway gliomas in 30 children with neurofibromatosis type 1, the indications of treatment, and the follow-up and screening protocol. PATIENTS AND METHODS: All patients with a minimal two years follow-up (median six years, range two to 19 years), in two multidisciplinary consultations of Saint-Vincent-de-Paul (Paris) and Purpan (Toulouse) hospitals, were included in the study. In our series, we practiced systematic screening MRI in children under six years' of age or with neuropsychological deficiency that may imply an unreliable ophthalmological examination. RESULTS: Thirty-seven percent (11 patients) had progressive ophthalmological signs and were treated, and 63% (19 patients) were not progressive. Our study confirmed that most of optic pathway gliomas were stable during evolution, but rare cases may have bad prognosis. CONCLUSION: Our study supported the importance of close ophthalmological follow-up during childhood for which screening methods are discussed. There is a consensus to limit treatment for patients with progressive ophthalmological symptoms.

Adolescent↗

PubMed2005

Phylogeny and life histories of the 'Insectivora': controversies and consequences.

The evolutionary relationships of the eutherian order Insectivora (Lipotyphla sensu stricto) are the subject of considerable debate. The difficulties in establishing insectivore phylogeny stem from their lack of many shared derived characteristics. The grouping is therefore something of a 'wastebasket' taxon. Most of the older estimates of phylogeny, based on morphological evidence, assumed insectivore monophyly. More recently, molecular phylogenies argue strongly against monophyly, although they differ in the extent of polyphyly inferred for the order. I review the history of insectivore phylogenetics and systematics, focussing on the relationships between the six extant families (Erinaceidae--hedgehogs and moonrats, Talpidae - moles and desmans, Soricidae - shrews, Solenodontidae--solenodons, Tenrecidae--tenrecs and otter-shrews and Chrysochloridae--golden moles). I then examine how these various phylogenetic hypotheses influence the results of comparative analyses and our interpretation of insectivore life-history evolution. I assess which particular controversies have the greatest effect on results, and discuss the implications for comparative analyses where the phylogeny is controversial. I also explore and suggest explanations for certain insectivore life-history trends: increased gestation length and litter size in tenrecs, increased encephalization in moles, and the mixed fast and slow life-history strategies in solenodons. Finally, I consider the implications for comparative analyses of the recent strongly supported phylogenetic hypothesis of an endemic African clade of mammals that includes the insectivore families of tenrecs and golden moles.

Animals↗

PubMed2002

Multiple origins of polyploidy in the phylogeny of southern African barbs (Cyprinidae) as inferred from mtDNA markers.

The cyprinid genus Barbus, with more than 800 nominal species, is an apparently polyphyletic assemblage to which a number of unrelated species, groups and/or assemblages have been assigned. It includes species that exhibit three different ploidy levels: diploid, tetraploid and hexaploid. Several lineages of the family Cyprinidae constitute a major component of the African freshwater ichthyofauna, having about 500 species, and fishes assigned to the genus 'Barbus' have the most species on the continent. We used complete sequences of the mitochondrial cytochrome b gene in order to infer phylogenetic relationships between diploid, tetraploid and hexaploid species of 'Barbus' occurring in southern Africa, the only region where representatives of all of the three ploidy levels occur. The results indicate that most of the lineages are incorrectly classified in the genus 'Barbus'. The southern African tetraploids probably originated from southern African diploids. They constitute a monophyletic group distinct from tetraploids occurring in the Euro-Mediterranean region (Barbus sensu stricto). The 'small' African diploid species seem to be paraphyletic, while the 'large' African hexaploid barbs species are of a single, recent origin and form a monophyletic group. The evidence of multiple, independent origins of polyploidy occurring in the African cyprinine cyprinids thus provides a significant contribution to the knowledge on the systematic diversity of these fishes, and warrants a thorough taxonomic reorganization of the genus.

Africa, Southern↗