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21.
Background
Biclustering has emerged as a powerful algorithmic tool for analyzing measurements of gene expression. A number of different methods have emerged for computing biclusters in gene expression data. Many of these algorithms may output a very large number of biclusters with varying degrees of overlap. There are no systematic methods that create a two-dimensional layout of the computed biclusters and display overlaps between them. 相似文献22.
Differences in the time course of proximal and distal airway response to inhaled histamine studied by synchrotron radiation CT. 总被引:1,自引:0,他引:1
Sam Bayat Liisa Porra Heikki Suhonen Christian Nemoz Pekka Suortti Anssi R A Sovij?rvi 《Journal of applied physiology》2006,100(6):1964-1973
We studied the kinetics of proximal and distal bronchial response to histamine aerosol in healthy anesthetized and mechanically ventilated rabbits up to 60 min after histamine administration using a novel xenon-enhanced synchrotron radiation computed tomography imaging technique. Individual proximal airway constriction was assessed by measuring the luminal cross-sectional area. Distal airway obstruction was estimated by measuring the ventilated alveolar area after inhaled xenon administration. Respiratory system conductance was assessed continuously. Proximal airway cross-sectional area decreased by 57% of the baseline value by 20 min and recovered gradually but incompletely within 60 min. The ventilated alveolar area decreased immediately after histamine inhalation by 55% of baseline value and recovered rapidly thereafter. The results indicate that the airway reaction to inhaled histamine and the subsequent recovery are significantly slower in proximal than in distal bronchi in healthy rabbit. The findings suggest that physiological reaction mechanisms to inhaled histamine in the airway walls of large and small bronchi are not similar. 相似文献
23.
Characterization of 3-chlorobenzoate degrading aerobic bacteria isolated under various environmental conditions 总被引:2,自引:0,他引:2
Krooneman J Sliekers AO Pedro Gomes TM Forney LJ Gottschal JC 《FEMS microbiology ecology》2000,32(1):53-59
The rates of bacterial growth in nature are often restricted by low concentrations of oxygen or carbon substrates. In the present study the metabolic properties of 24 isolates that had been isolated using various concentrations of 3-chlorobenzoate, benzoate and oxygen as well as using continuous culture at high and low growth rates were determined to investigate the effects of these parameters on the metabolism of monoaromatic compounds. Bacteria were enriched from different sampling sites and subsequently isolated. In batch culture this was done both under low oxygen (2% O(2)) and air-saturated concentrations. Chemostat enrichments were performed under either oxygen or 3-chlorobenzoate limiting conditions. Bacteria metabolizing aromatics with gentisate or protocatechuate as intermediates (gp bacteria) as well as bacteria metabolizing aromatic compounds via catechols (cat bacteria) were isolated from batch cultures when either benzoate or 3CBA were used as C sources, regardless of the enrichment conditions applied. In contrast, enrichments performed in chemostats at low dilution rates resulted in gp-type organisms only, whereas at high dilution rates cat-type organisms were enriched, irrespective of the oxygen and 3-chlorobenzoate concentration used during enrichment. It is noteworthy that the gp-type of bacteria possessed relatively low μ(max) values on 3CBA and benzoate along with relatively high substrate and oxygen affinities for these compounds. This is in contrast with cat-type of bacteria, which seemed to be characterized by high maximum specific growth rates on the aromatic substrates and relatively high apparent half saturation constants. In contrast, bacteria degrading chlorobenzoate via gentisate or protocatechuate may possibly be better adapted to conditions leading to growth at reduced rates such as low oxygen and low substrate concentrations. 相似文献
24.
RG Lockie AB Schultz SJ Callaghan CA Jordan TM Luczo MD Jeffriess 《Biology of sport / Institute of Sport》2015,32(1):41-51
There is little research investigating relationships between the Functional Movement Screen (FMS) and athletic performance in female athletes. This study analyzed the relationships between FMS (deep squat; hurdle step [HS]; in-line lunge [ILL]; shoulder mobility; active straight-leg raise [ASLR]; trunk stability push-up; rotary stability) scores, and performance tests (bilateral and unilateral sit-and-reach [flexibility]; 20-m sprint [linear speed]; 505 with turns from each leg; modified T-test with movement to left and right [change-of-direction speed]; bilateral and unilateral vertical and standing broad jumps; lateral jumps [leg power]). Nine healthy female recreational team sport athletes (age = 22.67 ± 5.12 years; height = 1.66 ± 0.05 m; body mass = 64.22 ± 4.44 kilograms) were screened in the FMS and completed the afore-mentioned tests. Percentage between-leg differences in unilateral sit-and-reach, 505 turns and the jumps, and difference between the T-test conditions, were also calculated. Spearman''s correlations (p ≤ 0.05) examined relationships between the FMS and performance tests. Stepwise multiple regressions (p ≤ 0.05) were conducted for the performance tests to determine FMS predictors. Unilateral sit-and-reach positive correlated with the left-leg ASLR (r = 0.704-0.725). However, higher-scoring HS, ILL, and ASLR related to poorer 505 and T-test performance (r = 0.722-0.829). A higher-scored left-leg ASLR related to a poorer unilateral vertical and standing broad jump, which were the only significant relationships for jump performance. Predictive data tended to confirm the correlations. The results suggest limitations in using the FMS to identify movement deficiencies that could negatively impact athletic performance in female team sport athletes. 相似文献
25.
BP ONeill TM Habermann TE Witzig M Rodriguez 《Cancer immunology, immunotherapy : CII》1999,16(3):211-215
Five patients at risk for primary central nervous system lymphoma (PCNSL) recurrence were treated with high-dose methylprednisolone,
(HDMP) to prevent ‘trafficking’ of malignant lymphocytes into the central nervous system (CNS). HDMP was chosen because of
its ability to stabilize the ‘blood brain barrier (BBB)’. Three men with newly diagnosed PCNSL, ages 62, 76 and 78 y, whose
survival was projected to be 6.6 months, began treatment after achieving complete response (CR) to initial radiation therapy
alone and survived 27, 37 and 59 months after treatment. In none was death from recurrent disease in CNS but one patient did
die of systemic non-Hodgkin’s lymphoma (NHL) five years after PCNSL diagnosis. A 20 y old man was treated with HDMP after
successful combined modality therapy and is alive 75+months after initial diagnosis without evidence of disease recurrence.
A 34 y old man relapsed after combined modality initial treatment and failed to respond to HDMP when treatment was begun after
unsuccessful salvage therapy; he died of disease 12 months after initial diagnosis. There were no treatment complications.
The promising results in this pilot study from the basis for a North Central Cancer Treatment Group (NCCTG) 96-73-51, a Phase
2 clinical trial of brain radiotherapy and HDMP for PCNSL patients 70 y of age and older, a group of patients at high risk
for toxicity from intensive combined modality therapy. 相似文献
26.
Introduction
Management of osteoarthritis (OA) includes the use of non-pharmacological and pharmacological therapies. Although walking is commonly recommended for reducing pain and increasing physical function in people with OA, glucosamine sulphate has also been used to alleviate pain and slow the progression of OA. This study evaluated the effects of a progressive walking program and glucosamine sulphate intake on OA symptoms and physical activity participation in people with mild to moderate hip or knee OA. 相似文献27.
Amrita Pati Cecilia Vasquez-Robinet Lenwood S Heath Ruth Grene TM Murali 《BMC bioinformatics》2006,7(1):218-14
Background
Modeling of cis-elements or regulatory motifs in promoter (upstream) regions of genes is a challenging computational problem. In this work, set of regulatory motifs simultaneously present in the promoters of a set of genes is modeled as a biclique in a suitably defined bipartite graph. A biologically meaningful co-occurrence of multiple cis-elements in a gene promoter is assessed by the combined analysis of genomic and gene expression data. Greater statistical significance is associated with a set of genes that shares a common set of regulatory motifs, while simultaneously exhibiting highly correlated gene expression under given experimental conditions. 相似文献28.
Miguel?Lacerda Penny?L?Moore Nobubelo?K?Ngandu Michael?Seaman Elin?S?Gray Ben?Murrell Mohan?Krishnamoorthy Molati?Nonyane Maphuti?Madiga Constantinos?Kurt?Wibmer Daniel?Sheward Robert?T?Bailer Hongmei?Gao Kelli?M?Greene Salim?S?Abdool?Karim John?R?Mascola Bette?TM?Korber David?C?Montefiori Lynn?Morris Carolyn?Williamson Cathal?SeoigheEmail author the CAVD-NSDP Consortium 《Virology journal》2013,10(1):347
Background
Identification of the epitopes targeted by antibodies that can neutralize diverse HIV-1 strains can provide important clues for the design of a preventative vaccine.Methods
We have developed a computational approach that can identify key amino acids within the HIV-1 envelope glycoprotein that influence sensitivity to broadly cross-neutralizing antibodies. Given a sequence alignment and neutralization titers for a panel of viruses, the method works by fitting a phylogenetic model that allows the amino acid frequencies at each site to depend on neutralization sensitivities. Sites at which viral evolution influences neutralization sensitivity were identified using Bayes factors (BFs) to compare the fit of this model to that of a null model in which sequences evolved independently of antibody sensitivity. Conformational epitopes were identified with a Metropolis algorithm that searched for a cluster of sites with large Bayes factors on the tertiary structure of the viral envelope.Results
We applied our method to ID50 neutralization data generated from seven HIV-1 subtype C serum samples with neutralization breadth that had been tested against a multi-clade panel of 225 pseudoviruses for which envelope sequences were also available. For each sample, between two and four sites were identified that were strongly associated with neutralization sensitivity (2ln(BF)?>?6), a subset of which were experimentally confirmed using site-directed mutagenesis.Conclusions
Our results provide strong support for the use of evolutionary models applied to cross-sectional viral neutralization data to identify the epitopes of serum antibodies that confer neutralization breadth.29.
Entomopathogenic nematodes (EPN) are efficient biological pest control agents. Population genetics studies on EPN are seldom
known. Therefore, it is of interest to evaluate the significance of molecular sampling method (MSM) for accuracy, time needed, and
cost effectiveness over traditional sampling method (TSM). The study was conducted at the Mohican Hills golf course at the state
of Ohio where the EPN H. bacteriophora has been monitored for 18 years. The nematode population occupies an area of
approximately 3700 m2 with density range from 0.25-2 per gram soil. Genetic diversity of EPN was studied by molecular sampling
method (MSM) and traditional sampling method (TSM) using the mitochondrial gene pcox1. The MSM picked 88% in compared to
TSM with only 30% of sequenced cox 1 gene. All studied genetic polymorphism measures (sequence and haplotype) showed high
levels of genetic diversity of MSM over TSM. MSM minimizes the chance of mitochondrial genes amplification from non target
organisms (insect or other contaminating microorganisms). Moreover, it allows the sampling of more individuals with a reliable
and credible representative sample size. Thus, we show that MSM supersedes TSM in labour intensity, time consumption and
requirement of no special experience and efficiency. 相似文献
30.
Yvonne P de Visser Frans J Walther El Houari Laghmani Hester Boersma Arnoud van der Laarse Gerry TM Wagenaar 《Respiratory research》2009,10(1):1-16