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At least 253 records · Page 14Linked to original sources
PubMed1999

Comparison of ZP3 protein sequences among vertebrate species: to obtain a consensus sequence for immunocontraception.

The deduced ZP3 amino acid (aa) sequences of 13 vertebrate species namely mouse, hamster, rabbit, pig, porcine, cow, dog, cat, human, bonnet, marmoset, carp, and frog were compared using the PILEUP and PRETTY alignment programs (GCG, Wisconsin, USA). The published aa sequences obtained from 13 vertebrate species indicated the overall evolutionarily conservation in the N-terminus, central region, and C-terminus of the ZP3 polypeptide. More variations of ZP3 polypeptide sequences were seen in the alignments of carp and frog from the 11 mammalian species making the leader sequence more prominent. The canonical furin proteolytic processing signal at the C-terminus was found in all the ZP3 polypeptide sequences except of carp and frog. In the central region, the ZP3 deduced aa sequences of all the 13 vertebrate species aligned well, and six relatively conserved sequences were found. There are 11 conserved cysteine residues in the central region across all species including carp and frog, indicating that these residues have longer evolutionary history. The ZP3 aa sequence similarities were examined using the GAP program (GCG). The highest aa similarities are observed between the members of the same order within the class mammalia, and also (95.4%) between pig (ungulata) and rabbit (lagomorpha). The deduced ZP3 aa sequences per se may not be enough to build a phylogenetic tree.

Amino Acid Sequence↗
PubMed1997

Disaster planning: meeting the challenge of 'killer' tornadoes.

In many areas of the country, tornadoes represent a major concern for hospitals in preparing disaster plans. Like all such plans, the hope is that they will not have to be put to use. But last spring, in areas of Arkansas and Texas, damage and casualties from twisters made national headlines and put the disaster plans of a number of hospitals to the test. For example, as part of the country's worst tornado outbreak since March 1994, twisters that tore through Arkansas from southwest to northeast on the afternoon of Saturday, March 1, killed 25 and injured hundreds. The tornadoes left a path of damaged buildings and downed trees more than 200 miles long. Three persons died in the Little Rock suburb of College Station. Warning sirens and TV and radio broadcasts a few minutes before the tornadoes hit were able to give area residents time to take cover, reducing the number of casualties. On May 27, tornadoes that hit three central Texas counties killed 32 people and left hundreds homeless. The small town of Jarrell was flattened by winds of up to 270 mph. In Cedar Park, about 20 miles south of Jarrell, a grocery store was demolished and a nearby shopping center had roofs torn off. Fortunately, there were relatively few injuries. In the area immediately around Jarrell, hospitals reported 33 casualties treated. The small number of injuries may have been the result of a large number of deaths, one official speculated. In this report, we'll give details on how nine hospitals in the affected areas dealt with tornado emergencies and how their disaster plans were carried out.

Arkansas↗
PubMed1992

[Structural typology assay of principal anticancer agents on the basis of molecular fragmentation].

The developed formula of 58 anticancer agents used in therapeutic or still in clinical essays were treated by molecular connectivity matrix method. This technic allows the search and the automatically count of structural fragments of the different studied molecules. Then it has been possible to build a spanning tree (Prim's arborescent skeleton) which gathers the different molecules and permits to put a priori new structures.

Antineoplastic Agents↗
PubMed2004

Predicting survival causes after out of hospital cardiac arrest using data mining method.

BACKGROUND: The prognosis of life for patients with heart failure remains poor. By using data mining methods, the purpose of this study was to evaluate the most important criteria for predicting patient survival and to profile patients to estimate their survival chances together with the most appropriate technique for health care. METHODS: Five hundred and thirty three patients who had suffered from cardiac arrest were included in the analysis. We performed classical statistical analysis and data mining analysis using mainly Bayesian networks. RESULTS: The mean age of the 533 patients was 63 (+/- 17) and the sample was composed of 390 (73 %) men and 143 (27 %) women. Cardiac arrest was observed at home for 411 (77 %) patients, in a public place for 62 (12 %) patients and on a public highway for 60 (11 %) patients. The belief network of the variables showed that the probability of remaining alive after heart failure is directly associated to five variables: age, sex, the initial cardiac rhythm, the origin of the heart failure and specialized resuscitation techniques employed. CONCLUSIONS: Data mining methods could help clinicians to predict the survival of patients and then adapt their practices accordingly. This work could be carried out for each medical procedure or medical problem and it would become possible to build a decision tree rapidly with the data of a service or a physician. The comparison between classic analysis and data mining analysis showed us the contribution of the data mining method for sorting variables and quickly conclude on the importance or the impact of the data and variables on the criterion of the study. The main limit of the method is knowledge acquisition and the necessity to gather sufficient data to produce a relevant model.

Bayes Theorem↗
PubMed2004

[The research on the karyotypes of six species in the genus Eremias from China].

Based on the Giemsa-dyeing karyotypes and silver-staining bands of 15 populations from different localities in China belonging to 6 species of the genus Eremias , We found all species studied have 19 pairs of chromosomes, the size of chromosomes reduces gradually and there are no marked differences between the arranged pairs of macrochromosomes except the last pair of microchromosome. There are the same karyotype formula as 2n=38=36I+2m with NF=38 in E. argus, E. multiocellata, E. velox, E. arguta and E. grammica; but the karyotype formula of E. vermiculata is different as 2n=38=12V+2sI+22I+2m with NF=50. The NOR are all located on one small pair in female of E. velox, and E. arguta , in male of E. grammica and E. vermiculata ,and in both male and female of E. multiocellata. We have not found two or more than two pairs of NOR. Having one pair of NOR may be common in Genus Eremias and also the trait of Eremias. We speculate that the derivation of the karyotype of E. vermiculata had two possible way: one experienced the stage of triploid, and later the Robertsonian transposal of chromosomes; the other way was through the inversions between the arms on the chromosome and the phenomenon of inversions might occur during or subsequently after the upheaval of the Tibet and Qinghai plateau and the founding of the Tianshan . With regard to the trend of the evolution of chromosomes in the lizards ([1]), the karyotype of E. vermiculata is more advanced. Making specialties of E. vermiculata will help in building the phylogenic tree of Eremias. In both male and female of the species studied, the heteromorphic sex-chromosomes were not found.

Animals↗
PubMedDate not supplied

[The manipulation of information of developed formulas for the study of structure-activity relationships. Application to antiparasitic agents].

Beside traditional univariate methods of pharmacochemical (pharmacomodulation...), and of molecular pharmacology ("binding"...) most global approach (multivariate) of structure-activity and structure-toxicity relationships may been in action with processing implement. Developed formula may been treated by different algorithmic methods as molecular connectivity matrix which use atoms, bindings, chemical functions, fragments, of any molecule. This technique allows to research and to automatically count structural fragments of molecule, different in their chemical aspect but having the same port of activity. So, with this profile of fragments it is possible to build a spanning tree (PRIM'S arborescent skeleton) and to place a priori on it, new structures with other properties to value their activity level in the designed field. We applied these techniques to 50 most prescribed antiparasitic active principles.

Information Systems↗
PubMedDate not supplied

Decision analysis in the clinical and imaging diagnosis of acute cholecystitis.

The importance of clinical, laboratory and imaging data in the diagnosis of acute cholecystitis (AC) was studied in 825 patients with right upper quadrant pain hospitalized in the Surgical Clinic of the Fundeni Hospital--Bucharest, between January 1, 1986 and June 30, 1988. A number of 21 parameters were analysed in each case. Of these 825 patients, 259 were considered after surgery as AC. These 259 cases were divided, after the microscopical examination of the surgically-obtained specimens, into two groups: 1) pathologically confirmed AC (137 cases) and 2) pathologically non-confirmed AC (122 cases). The importance of every parameter in establishing a histologically confirmed diagnosis of AC was determined by the diagnostic probability calculated according to Bayes'theorem. The hierarchy of the value of parameters in the diagnosis of AC was based on their capacity to distinguish between the cases histologically confirmed and those detected on surgery, but without microscopically demonstrated changes of AC. The same decision criterion was used in building the decision trees in the exploration of the cases of presumed AC. In the 825 cases with right upper quadrant pain, the main and most frequent cause was chronic calculous cholecystitis (31.8%), followed by AC pathologically confirmed (16.6%), AC non-confirmed (14.7%) and chronic acalculous cholecystitis (12.4%). The most useful parameters in distinguishing between pathologically confirmed AC and pathologically non-confirmed AC were: 1) sudden onset of pain; 2) mild resistance to abdominal palpation; 3) frank peritoneal irritation; 4) stone impacted in the gallbladder neck (ultrasonography); 5) fever; 6) palpable gallbladder; 7) lithiasis (ultrasonography); 8) gallbladder wall with double outline (ultrasonography). Ultrasonography supplied a diagnostic probability of 85% for the correct diagnosis of AC in cases without a clinical picture suggestive for AC. The decision tree analysis supported the same conclusion: only ultrasonography gives a good distinction between pathologically confirmed AC and pathologically non-confirmed AC.

Acute Disease↗
PubMed1993

Protein structure prediction: selecting salient features from large candidate pools.

We introduce a parallel approach, "DT-SELECT," for selecting features used by inductive learning algorithms to predict protein secondary structure. DT-SELECT is able to rapidly choose small, nonredundant feature sets from pools containing hundreds of thousands of potentially useful features. It does this by building a decision tree, using features from the pool, that classifies a set of training examples. The features included in the tree provide a compact description of the training data and are thus suitable for use as inputs to other inductive learning algorithms. Empirical experiments in the protein secondary-structure task, in which sets of complex features chosen by DT-SELECT are used to augment a standard artificial neural network representation, yield surprisingly little performance gain, even though features are selected from very large feature pools. We discuss some possible reasons for this result.

Algorithms↗
PubMed1994

Turning medical data into decision-support knowledge.

Advances in information collection and analysis are reaching the point of providing physicians with the help of computer-based assistants. These systems will provide rapid second opinions to physicians in a clinical setting as well as assist them in the analysis of large sets of patient descriptions for research purposes. This paper presents INC2.5 as such a decision-support system. INC2.5 extracts information from databases of previously seen patients to build a decision tree which is used to predict the outcome of new patients on a chosen variable. The concept of matching new patients with the most similar previously seen patient, on which INC2.5 is based, can be easily understood by its users. Further adding to INC2.5's ease of use is its flexibility in allowing users to customize decision trees to their liking. In order to convey the uncertainty of the environment, INC2.5 presents all decisions with a confidence factor.

Classification↗
PubMed1993

Cell interactions underlying Purkinje cell replacement by neural grafting in the pcd mutant cerebellum.

The results obtained with neuronal grafting in an animal model of heredo-degenerative ataxia (the pcd mutant mouse) have been extremely useful to unmask new aspects of neural plasticity. The grafted embryonic Purkinje cells invade the deficient molecular layer of the host by migrating radially through adult Bergmann fibers. There, they start building their dendritic trees and, by promoting the axonal sprouting of specific adult neuronal population in a timed sequence, they receive appropriate synaptic contacts, starting ten days after grafting. Twenty-one days after grafting, the grafted Purkinje cells have acquired their adult dendritic pattern and synaptic investment. Both the detailed timetable and the nature of the cellular interactions between embryonic and adult neural cells are remarkably similar to those occurring during normal development. These results raise the possibility that embryonic Purkinje cells can induce in adult neural cells a new type of plasticity, that of recreating a permissive microenvironment for the synaptic integration of the grafted neurons, leading to the anatomical restoration of the cortical circuit of the mutant cerebellum.

Animals↗
PubMed1984

[Use of the personal computer for the study of biological images].

In order to study anatomical structures, a computerized system was developed to build planar and tree-dimensional models. The hardware utilizes an external synchronizing telecamera to magnify the image on a personal computer monitor screen, which is utilized as a cartesian plain, to extract the x-y co-ordinates of some reference points from the image. The computer stores and utilizes them to evaluate geometrical parameters (area and volume) and to build planar or tree-dimensional models.

Computers↗
PubMed2001

Strontium isotopes reveal distant sources of architectural timber in Chaco Canyon, New Mexico.

Between A.D. 900 and 1150, more than 200,000 conifer trees were used to build the prehistoric great houses of Chaco Canyon, New Mexico, in what is now a treeless landscape. More than one-fifth of these timbers were spruce (Picea) or fir (Abies) that were hand-carried from isolated mountaintops 75-100 km away. Because strontium from local dust, water, and underlying bedrock is incorporated by trees, specific logging sites can be identified by comparing (87)Sr/(86)Sr ratios in construction beams from different ruins and building periods to ratios in living trees from the surrounding mountains. (87)Sr/(86)Sr ratios show that the beams came from both the Chuska and San Mateo (Mount Taylor) mountains, but not from the San Pedro Mountains, which are equally close. Incorporation of logs from two sources in the same room, great house, and year suggest stockpiling and intercommunity collaboration at Chaco Canyon. The use of trees from both the Chuska and San Mateo mountains, but not from the San Pedro Mountains, as early as A.D. 974 suggests that selection of timber sources was driven more by regional socioeconomic ties than by a simple model of resource depletion with distance and time.

Journal Article↗
PubMed2001

Body building and concurrent mass loss: flight adaptations in tree sparrows.

Environmental changes are responsible for the evolution of flexible physiology and the extent of phenotypic plasticity in the regulation of birds' organ size has not been appreciated until recently. Rapid reversible physiological changes during different life-history stages are virtually only known from long-distance migrants, and few studies have focused on less extreme aspects of organ flexibility. During moult, birds suffer from increased wing loading due to wing-area reductions, which may impair flight ability. A previous study found that tree sparrows' escape flight (Passer montanus) is unaffected during moult, suggesting compensatory aptness. We used non-invasive techniques to study physiological adaptations to increased wing loading in tree sparrows. As wing area was reduced during natural moult the ratio of pectoral-muscle size to body mass increased. When moult was completed this ratio decreased. We show experimentally a novel, strategic, organ-flexibility pattern. Unlike the general pattern, where body mass is positively coupled to pectoral-muscle size, tree sparrows responded within 7 days to reductions in wing area by reducing body mass concurrently with an increase in pectoral-muscle size. This rapid flexibility in a non-migratory species probably reflects the paramount importance and long history of flight in birds.

Adaptation, Physiological↗
PubMed2000

Anatomy of protein structures: visualizing how a one-dimensional protein chain folds into a three-dimensional shape.

Here, we depict the anatomy of protein structures in terms of the protein folding process. Via an iterative, top-down dissecting procedure, tertiary structures are spliced down to reveal their anatomy: first, to produce domains (defined by visual three-dimensional inspection criteria); then, hydrophobic folding units (HFU); and, at the end of a multilevel process, a set of building blocks. The resulting anatomy tree organization not only clearly depicts the organization of a one-dimensional polypeptide chain in three-dimensional space but also straightforwardly describes the most likely folding pathway(s). Comparison of the tree with the formation of the hydrophobic folding units through combinatorial assembly of the building blocks illustrates how the chain folds in a sequential or a complex folding pathway. Further, the tree points to the kinetics of the folding, whether the chain is a fast or a slow folder, and the probability of misfolding. Our ability to successfully dissect the protein into an anatomy tree illustrates that protein folding is a hierarchical process and further validates a building blocks protein folding model.

Actins↗
PubMed2000

A binary spelling interface with random errors.

An algorithm for design of a spelling interface based on a modified Huffman's algorithm is presented. This algorithm builds a full binary tree that allows to maximize an average probability to reach a leaf where a required character is located when a choice at each node is made with possible errors. A means to correct errors (a delete-function) and an optimization method to build this delete-function into the binary tree are also discussed. Such a spelling interface could be successfully applied to any menu-orientated alternative communication system when a user (typically, a patient with devastating neuromuscular handicap) is not able to express an intended single binary response, either through motor responses or by using of brain-computer interfaces, with an absolute reliability.

Algorithms↗
PubMed2005

Geographical traceability of West Liguria extravirgin olive oils by the analysis of volatile terpenoid hydrocarbons.

This study aimed at evaluating if the volatile terpenoid hydrocarbons of extravirgin olive oils from West Liguria, a North Italy region, could trace their geographical origin. If terpenoid hydrocarbons were individually considered, three compounds, i.e. alpha-copaene, alpha-muurolene and alpha-farnesene, allowed building a simple decision tree and discriminating oils produced in West Liguria from oils produced in other Mediterranean regions. Moreover, the multivariate analysis allowed building West Liguria class-models with high predictive ability, confirming the fundamental role of the volatile terpenoid hydrocarbons for the geographical characterisation of West Liguria oils.

Gas Chromatography-Mass Spectrometry↗
PubMed2002

Observation of assembly of fluorescent Si nanoparticles under the influence of electric current.

A silicon substrate patterned by an oxide is immersed in an alcohol solution of low-doped 1-nm Si nanoparticles. Reverse biasing draws particles to the substrate, mostly along the conducting current paths. Scanning electron and fluorescence microscopy show a tree-like network on the substrate. Avoidance of closed loops and preference for an angle of branching of 90 degrees-120 degrees are observed. The building block of the tree network is not individual particles but spherical particle aggregates approximately 150 nm in diameter.

Colloids↗