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PubMed2004

Evolutionary and biogeographic patterns of the Badidae (Teleostei: Perciformes) inferred from mitochondrial and nuclear DNA sequence data.

We reconstructed phylogenetic relationships of the family Badidae using both mitochondrial and nuclear nucleotide sequence data to address badid systematics and to evaluate the role of vicariant speciation on their evolution and current distribution. Phy-logenetic hypotheses were derived from complete cytochrome b (1,140 base pairs) sequences of 33 individuals representing 13 badid species, and using three species of Nandidae as outgroups. Additionally, we sequenced the nuclear RAG1 (1,473 base pairs) and Tmo-4C4 (511 base pairs) genes from each of the badid species and one representative of the outgroup. Our molecular data provide the first phylogenetic hypothesis of badid intrarelationships. Analysis of the mitochondrial and nuclear nucleotide sequence data sets resulted in well-supported trees, indicating a basal split between the genera Dario and Badis, and further supporting the division of the genus Badis into five species groups as suggested by a previous taxonomic revision of the Badidae. Within the genus Badis, mitochondrial and nuclear phylogenies differed in the relative position of B. kyar. We also used our molecular phylogeny to test a vicariant speciation hypothesis derived from geological evidence of large-scale changes in drainage patterns in the Miocene affecting the Irrawaddy- and Tsangpo-Brahmaputra drainages, in the southeastern Himalaya. Within both genera, Badis and Dario, we observed a divergence into Irrawaddy- and Tsangpo-Brahmaputra clades. Using a cytb substitution rate of 8.2 x 10(-9) (substitutions x base pair(-1) x year(-1), we tentatively date this vicariant event at the Oligocene-Miocene boundary (19-24Myr). It is concordant with a hypothesized paleo connection of the Tsangpo river with the Irrawaddy drainage that was most likely interrupted during Miocene orogenic events through tectonic uplifts in eastern Tibet. Our data, therefore, indicate a substantial role of vicariant-based speciation shaping the current distribution patterns of badids.

Animals↗

PubMed2002

Computer applications in the search for unrelated stem cell donors.

The majority of patients which are eligible for a blood stem cell transplantation from an allogeneic donor do not have a suitable related donor so that an efficient unrelated donor search is a prerequisite for this treatment. Currently, there are over 7 million volunteer donors in the files of 50 registries in the world and in most countries the majority of transplants are performed from a foreign donor. Evidently, computer and communication technology must play a crucial role in the complex donor search process on the national and international level. This article describes the structural elements of the donor search process and discusses major systematic and technical issues to be addressed in the development and evolution of the supporting telematic systems. The theoretical considerations are complemented by a concise overview over the current state of the art which is given by describing the scope, relevance, interconnection and technical background of three major national and international computer appliances: The German Marrow Donor Information System (GERMIS) and the European Marrow Donor Information System (EMDIS) are interoperable business-to-business e-commerce systems and Bone Marrow Donors World Wide (BMDW) is the basic international donor information desk on the web.

Bone Marrow Transplantation↗

PubMed2005

Effect of the tube diameter distribution on the high-temperature structural modification of bundled single-walled carbon nanotubes.

We present results of a systematic high-resolution transmission electron microscopy study of the thermal evolution of bundled single-walled carbon nanotubes (SWNTs) subjected to approximately 4-h high-temperature heat treatment (HTT) in a vacuum at successively higher temperatures up to 2200 degrees C. We have examined purified SWNT material derived from the HiPCO and ARC processes. These samples were found to thermally evolve along very different pathways that we propose depend on three factors: (1) initial diameter distribution, (2) concomitant tightness of the packing of the tubes in a bundle, and (3) the bundle size. Graphitic nanoribbons (GNR) were found to be the dominant high-temperature filament in ARC material after HTT = 2000 degrees C; they were not observed in any heat-treated HiPCO material. The first two major steps in the thermal evolution of HiPCO and ARC material agree with the literature, i.e., coalescence followed by the formation of multiwall carbon nanotubes (MWNTs). However, ARC material evolves to bundled MWNTs, while HiPCO evolves to isolated MWNTs. In ARC material, we find that the MWNTs collapse into multishell GNRs. The thermal evolution of these carbon systems is discussed in terms of the diameter distribution, nanotube coalescence pathways, C-C bond rearrangement, diffusion of carbon and subsequent island formation, as well as the nanotube collapse driven by van der Waals forces.

Journal Article↗

PubMed1976

Learning objectives in resident training. Objectives in clinical chemistry.

The use of learning objectives has recently found extensive application in the evolution of medical school curricula; however, they have not been utilized systematically in the education of pathology residents. In attempting to define the end-point behavior or objectives of a resident during a rotation in clinical biochemistry, 567 midwestern pathologists, clinical chemists and medical technologists working in chemistry sections rated proposed objectives as essentail, desirable but not essential, or not needed. Twenty-four of 52 objectives were considered essential for the resident to achieve by 75% or more of the respondents. These included 10 of 33 related to technical knowledge, 5 to 10 related to business and supervisory skills, 5 of 5 related to investigative problem solving, and 4 of 4 related to communicating with persons outside of the laboratory. In general, respondents considered knowledge of principles more important than technical skills. Management, business and communicative skills were highly rated.

Chemistry, Clinical↗

PubMed2000

Epistaxis: a review.

Epistaxis, being the commonest ear, nose and throat (ENT) emergency requiring hospital admission, is clearly an important condition--not only to the specialist but also to any general practitioner. This short review looks at the aetiology, associated clinical considerations (especially those of hypertension and hypoxaemia) and evolution of its management. Herein is also suggested a methodical and systematic approach to treating the disorder, both at the level of the accident and emergency department and at that of in-patient care. The patient with epistaxis of a refractory nature is included, too--along with a selection of the options available for treatment.

Cautery↗

PubMed1991

Phylogenetic analysis of Alloglossidium Simer, 1929 (Digenea: Plagiorchiiformes: Macroderoididae) with discussion of the origin of truncated life cycle patterns in the genus.

Alloglossidium comprises 9 species of North American plagiorchiiform digeneans using ictalurid catfish, freshwater crustacea, and hirudinid leeches as definitive hosts. Two hypotheses about the evolution of this array of definitive hosts were examined using phylogenetic systematic analysis. Two most parsimonious trees, based on 15 homologous series derived from morphological data, each indicated the 2 species utilizing ictalurid catfish definitive hosts are basal members of the group, whereas the 2 species using freshwater crayfish definitive hosts and the 5 utilizing leech definitive hosts each comprise relatively derived monophyletic sister groups. The results suggest that species using crustaceans as definitive hosts are derived by life cycle truncation, whereas those using leeches as definitive hosts appear to be derived through a switch from crustaceans to leeches.

Animals↗

PubMed1993

[Sideroses of alveolar macrophages. Analysis of a continuous series of 360 bronchoalveolar lavages].

360 consecutive bronchoalveolar lavage fluids (BAL) were studied using semi-quantitative method described by GOLDE (GOLDE score). 44 hemosiderosis were detected (12%). Most of them corresponded to massive alveolar hemorrhage (AH). Depending on pathological contexts, we distinguished three main groups of AH frequency: a group of high frequency (around 40%), an intermediate group (10%) and a low frequency group with less than 5%. Matching cytological results with clinical and radiological data, revealed that AH was often too late diagnosed because inconstancy of typical clinical and radiological signs. Even with a variable prognosis related to different physiopathological mechanisms, AH evolution is unpredictable. The authors suggest thus BAL cytological examination may systematically include a research of hemosiderosis in AH high frequency groups.

Acquired Immunodeficiency Syndrome↗

PubMed1993

[The Griscelli-Prunieras syndrome: a case report].

It is presented a six-year-old girl with silvered hair syndrome, of Griscelli-Prunieras variety; hereditary sickness with regressive autosomic and distinguished by partial albinism and leukocytic alterations. She presented the acute phase of the sickness distinguished by: hepatosplenomegaly, thrombocytopenia, lymphadenopathy generalized, and systematic infection; it is corroborated how a hemophagocytic syndrome; during her evolution developed pancerebellar syndrome. By laboratory were corroborated: decrease phagocytosis, degranulation 0%, decrease of globulins gamma, neutropenia, skin test of PPD and Candidin negatives, there were not find the giant inclusions in bone marrow leukocyte and peripheric blood that are feature of Chediak-Higashi syndrome. Another alteration that was the distribution of mote of melanin on the hair that in the Griscelli-Prunieras syndrome are six times bigger in the Chediak-Higashi syndrome.

Acute Disease↗

PubMed2001

Chronic lymphocytic leukemia associated with myelodysplastic syndrome and/or chronic myeloid leukemia: evidence for independent clonal chromosomal evolution.

We describe the cytogenetic findings of three cases with simultaneous or sequential development of a B-chronic lymphocytic leukemia (B-CLL) and either a myelodysplastic syndrome (MDS) in 2 cases or a chronic myeloid leukemia (CML) in one case. The coexistence of these two hematologic malignancies leads to questions about their cell of origin. Through analysis of the cytogenetic abnormalities, we studied the derivation of both malignancies. The cytogenetic analyses of these three patients were simultaneously studied from both peripheral blood and bone marrow. Furthermore unstimulated short-time (USSTC) and long-time (72-96 hours) stimulated cultures (LTSC) were systematically performed. In all cases, we have demonstrated the independent bi-clonal evolution. This is the first report ever described for patients with CLPD and MDS and/or MPD shown to arise from distinct chromosomal abnormalities.

Aged↗

PubMed1994

Archaebacterial genomes: eubacterial form and eukaryotic content.

Since the recognition of the uniqueness and coherence of the archaebacteria (sometimes called Archaea), our perception of their role in early evolution has been modified repeatedly. The deluge of sequence data and rapidly improving molecular systematic methods have combined with a better understanding of archaebacterial molecular biology to describe a group that in some ways appears to be very similar to the eubacteria, though in others is more like the eukaryotes. The structure and contents of archaebacterial genomes are examined here, with an eye to their meaning in terms of the evolution of cell structure and function.

Archaea↗

PubMed1993

[Alzheimer's disease followed in a single case].

Descriptions of Alzheimer's disease are usually based on the observation of populations of patients. Their advantage is the systematic analysis of signs and symptoms according to a logical approach enumerating the involvement of neurological, neuropsychological, affective and behavioral fields. Their disadvantage is to neglect the natural evolutive way and the subtle gearing of these diverse aspects of the disease. This paper aspires to bring a complement to the necessary systematic knowledge, by the description of a patient who has been followed regularly every 3 months for 4 and a half years. It describes the evolution as it is lived by the patient and his spouse, and as it is observed by the clinician. Three main facts are inferred. The first is the precocious involvement of two functions particularly affected later: language and the ability of identifying others. The second is with the evolution of the disease the identification, in the neuropsychological domain, of some tests which show no or little alteration, of some others altered from the outset, the majority deteriorating progressively. The third is the observation of a brisk and definitive worsening following a transient ischemic attack, demonstrating the vulnerability of these patients when the disease has reached an advanced stage.

Activities of Daily Living↗

PubMed1998

Analogous enzymes: independent inventions in enzyme evolution.

It is known that the same reaction may be catalyzed by structurally unrelated enzymes. We performed a systematic search for such analogous (as opposed to homologous) enzymes by evaluating sequence conservation among enzymes with the same enzyme classification (EC) number using sensitive, iterative sequence database search methods. Enzymes without detectable sequence similarity to each other were found for 105 EC numbers (a total of 243 distinct proteins). In 34 cases, independent evolutionary origin of the suspected analogous enzymes was corroborated by showing that they possess different structural folds. Analogous enzymes were found in each class of enzymes, but their overall distribution on the map of biochemical pathways is patchy, suggesting multiple events of gene transfer and selective loss in evolution, rather than acquisition of entire pathways catalyzed by a set of unrelated enzymes. Recruitment of enzymes that catalyze a similar but distinct reaction seems to be a major scenario for the evolution of analogous enzymes, which should be taken into account for functional annotation of genomes. For many analogous enzymes, the bacterial form of the enzyme is different from the eukaryotic one; such enzymes may be promising targets for the development of new antibacterial drugs.

Amino Acid Sequence↗

PubMed2005

Phylogenetic analysis of the main neutralization and hemagglutination determinants of all human adenovirus prototypes as a basis for molecular classification and taxonomy.

Human adenoviruses (HAdV) are responsible for a wide spectrum of diseases. The neutralization epsilon determinant (loops 1 and 2) and the hemagglutination gamma determinant are relevant for the taxonomy of HAdV. Precise type identification of HAdV prototypes is crucial for detection of infection chains and epidemiology. epsilon and gamma determinant sequences of all 51 HAdV were generated to propose molecular classification criteria. Phylogenetic analysis of epsilon determinant sequences demonstrated sufficient genetic divergence for molecular classification, with the exception of HAdV-15 and HAdV-29, which also cannot be differentiated by classical cross-neutralization. Precise sequence divergence criteria for typing (<2.5% from loop 2 prototype sequence and <2.4% from loop 1 sequence) were deduced from phylogenetic analysis. These criteria may also facilitate identification of new HAdV prototypes. Fiber knob (gamma determinant) phylogeny indicated a two-step model of species evolution and multiple intraspecies recombination events in the origin of HAdV prototypes. HAdV-29 was identified as a recombination variant of HAdV-15 (epsilon determinant) and a speculative, not-yet-isolated HAdV prototype (gamma determinant). Subanalysis of molecular evolution in hypervariable regions 1 to 6 of the epsilon determinant indicated different selective pressures in subclusters of species HAdV-D. Additionally, gamma determinant phylogenetic analysis demonstrated that HAdV-8 did not cluster with -19 and -37 in spite of their having the same tissue tropism. The phylogeny of HAdV-E4 suggested origination by interspecies recombination between HAdV-B (hexon) and HAdV-C (fiber), as in simian adenovirus 25, indicating additional zoonotic transfer. In conclusion, molecular classification by systematic sequence analysis of immunogenic determinants yields new insights into HAdV phylogeny and evolution.

Adenovirus Infections, Human↗

PubMed1989

Gross morphology and evolution of the mechanoreceptive lateral-line system in teleost fishes.

The morphology and development of the mechanoreceptive lateral-line system in teleost fishes is reviewed, and the systematic distribution of defined types of lateral-line systems is summarized. The importance of an understanding of ontogeny is stressed and the roles of phylogenetic and developmental constraints in the evolution of the lateral-line system are discussed. Four types of head canal systems are identified on the basis of the relative development of the canals and the orientation of the neuromast receptors contained within them. The distribution of these patterns in the four major teleost clades is analyzed. It is suggested that a branched tubule system associated with the head canals is a primitive teleost character, while widened and reduced head canal patterns are convergent functional specializations in many taxa. The trunk canals are contained in a continuous series of lateral-line scales, and eight trunk canal patterns are described in teleosts. Given the correlation of the systematic distribution of the different trunk canal patterns, ecological habit and body shape, it appears that the trunk canals may function as a hydrodynamic monitor in swimming fishes.

Animals↗

PubMed2001

[Genetics and the origin of human races].

In the last decades, the concept of human races was considered scientifically unfounded as it was not confirmed by genetic evidence. None of the racial classifications, which strongly differ in the number of races and their composition, reflects actual genetic similarity and genealogy of human populations inferred from variability of classical markers and DNA regions. Moreover, intercontinental ("interracial") variability was shown to be far lower than that within populations: the former constitutes 7 to 10% and the latter, about 85% of the total genetic variation. It is believed that the low level of differentiation of regional population groups contradicts their race status and suggests a recent origin of humans from one ancestral population. The results of studies of various genetic systems are in agreement with last conclusion rejecting the hypothesis of regional continuity. According to this hypothesis, the populations of continents regarded as large races have developed during long evolution from local types of archaic humans, in particular, Neanderthals. Phenotypic similarity of different, sometimes unrelated, populations united into one "race" is explained by strong selection since race-diagnostic traits characterize body surface and thus are directly subjected to the influence of environmental (primarily climatic) factors. It has been recently established that variability of the most important of these traits, body and hair pigmentation, is largely controlled by one locus (MC1R), which accounts for its high evolutionary lability. Other traits used for race identification are also likely to be labile and controlled by major genes. However, the fact that the currently existing race classifications are groundless does not mean that such classifications are impossible in principle. Commonly used argumentation (races do not exist because populations are not genetically separated) does not hold water. A polytypic species is characterized by genetic continuity of allopatric populations rather than the presence of narrow genetic boundaries between them. Borderlines between races are usually conventional and arbitrary. As to intergroup variation in humans, it is indeed low but comparable with that in some other species. There are no obstacles to the development of genetic systematics of human races.

Biological Evolution↗

PubMed2005

[Hemolytic uremic syndrome as a complication of gemcitabine treatment: report of six cases and review of the literature].

UNLABELLED: Hemolytic uremic syndrome is a rare condition during gemcitabine therapy. METHODS: We report six new cases of hemolytic uremic syndrome related to gemcitabine, three issued from a retrospective study of 136 consecutive patients treated with gemcitabine for which a systematic screening of this side effect has been performed and 29 cases with clinical data available identified in the literature in order to better characterised frequency and clinical presentation of this side effect. RESULTS: In our series, frequency of HUS is 2.2% and is higher than this previously reported (0.015%) or estimated with the data of clinical trials analysed (0.072 %). For 35 cases with clinical data available, the patients were always treated for a local advanced and/or metastatic disease. For our cases and for literature cases, at the time of diagnosis of hemolytic uremic syndrome, mean number of doses received (mean+/-standard deviation. Minimum/maximum)) (personal cases: 26.5+/-6.6. 16/36, literature cases: 21+/-11. 8/54), cumulative dose received (g/m2) (personal cases : 24.5+/-6.3. 16/31.6, literature cases: 21.7+/-12.4. 2.4/54) and duration of treatment (months) (personal cases: 8.2+/-1.9. 5.6/11, literature cases: 8.5+/-4.0. 3/18) are very closed and high individual variations observed for these factors are not consistent with a time and/or dose dependant toxicity. New-onset hypertension or exacerbation of underlying hypertension is the most common clinical manifestation, with mild anemia; thrombocytopenia is inconstant. The degree of severity of renal failure is highly variable. The existence of subacute clinical form with progressive worsening of the symptoms and biological form at the time of diagnosis suggest the interest of a systematic clinical and biological screening of this side effect, before each injection of gemcitabine. Early prognosis is linked to the evolution of hemolytic uremic syndrome and after hemolytic uremic syndrome healing, cancer progression. Treatment include gemcitabine discontinuation, antihypertensive drugs and if necessary fresh frozen plasma. CONCLUSIONS: Systematic clinical and biological screening of hemolytic uremic syndrome during gemcitabine therapy should allow to better know this complication, to recognize and treat it earlier with a potential positive impact for patients.

Aged↗

PubMed1995

The evolution of haematopoietic cytokine/receptor complexes.

The evolutionary expansion of the haematopoietic cytokines and their receptors is characterized by the duplication of both cytokines and receptors. A systematic analysis of primary sequence homology indicates that receptors for gp130-associated cytokines group into signal transducing and non-signal transducing receptors. This observation is consistent with the evolution of the interleukins 6, 11 and 12, granulocyte colony stimulating factor (G-CSF), leukemia inhibitory factor (LIF), oncostatin M, and the ciliary neurotrophic factor complexes from a common ancestral complex which included a homodimer of gp130-like signalling receptors and an interleukin 6 receptor-like non-signalling receptor. Alterations in the components of the complex are proposed to have arisen by receptor duplication and divergence to allow signal transduction via a LIF receptor/gp130 heterodimer, and loss of the non-signalling receptor component in the G-CSF and the LIF lineage. The short-chain haematopoietins and their receptors do not group clearly, although interleukins 4 and 13 grouped together, as did 2 and 10. Internal duplication of the ligand-binding domain appears to have occurred independently in three separate lineages. These observations have implications for the classification of cytokines and receptors, and for the modelling by homology of their structures and interactions.

Amino Acid Sequence↗

PubMed1998

Molecular epidemiology of enteroviruses with special reference to their potential role in the etiology of insulin-dependent diabetes mellitus (IDDM). A review.

BACKGROUND: Several lines of evidence suggest that enterovirus infections may be involved in the etiology of the insulin-dependent diabetes mellitus (IDDM). Often in the literature, a reference is given to specifically diabetogenic strains of enterovirus but there is no systematic assessment about the generation of such strains in the course of evolution or about their abundance among the 64 enterovirus serotypes pathogenic to man. If enteroviruses truly are involved in the etiology of IDDM, a possibility to prevent the disease with enterovirus vaccines might become feasible. In such a situation it would be important to know which serotypes and strains are the most important ones, and whether there would be differences between the strains as regards the pathogenetic mechanisms involved. OBJECTIVE: To present a brief summary of the basic biology of enteroviruses, on existing data of genetic variation of enteroviruses, and on molecular epidemiology of human enteroviruses with special reference to the different epidemiological modes of their putative involvement in the pathogenesis of IDDM. CONCLUSIONS: Like RNA viruses in general, enteroviruses exist as a quasispecies, a mixture of genetic microvariants with a vast potential to adapt to new environments. This means that specifically beta cell-tropic and potentially diabetogenic variants could, in theory, emerge sporadically during systemic infection of any individual. The patterns of genetic diversification of enteroviruses, cocirculation of separate genetic lineages in the human populations, and the assumed geographical restrictions of endemic transmission of the lineages, allow one to hypothesize that populations with a high persisting IDDM incidence might be endemically infected by some specific strains of enteroviruses. However, so far, there is no systematically collected data supporting this hypothesis.

Amino Acid Sequence↗