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51.
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Unbiased pattern detection in microarray data series   总被引:1,自引:0,他引:1  
MOTIVATION: Following the advent of microarray technology in recent years, the challenge for biologists is to identify genes of interest from the thousands of genetic expression levels measured in each microarray experiment. In many cases the aim is to identify pattern in the data series generated by successive microarray measurements. RESULTS: Here we introduce a new method of detecting pattern in microarray data series which is independent of the nature of this pattern. Our approach provides a measure of the algorithmic compressibility of each data series. A series which is significantly compressible is much more likely to result from simple underlying mechanisms than series which are incompressible. Accordingly, the gene associated with a compressible series is more likely to be biologically significant. We test our method on microarray time series of yeast cell cycle and show that it blindly selects genes exhibiting the expected cyclic behaviour as well as detecting other forms of pattern. Our results successfully predict two independent non-microarray experimental studies.  相似文献   
53.
Zusammenfassung Vfn. empfiehlt die Einführung des Punktzählverfahrens als quantitative Methode in die Histochemie und zeigt Möglichkeiten für dessen Anwendung auf. Das Verfahren eignet sich sehr gut für solche histochemischen. Untersuchungen, bei denen mit Relativwerten gearbeitet werden kann, sowie zu vergleichenden Untersuchungen. Die an das Objekt zu stellenden und die von der Methode her bestimmten Voraussetzungen für die Anwendung des Punktzählverfahrens werden besprochen. An Hand eines Beispiels werden Anregungen zur variationsstatistischen Auswertung des gewonnenen Zahlenmaterials vermittelt.  相似文献   
54.

Background

Diagnosis of urogenital schistosomiasis by microscopy and serological tests may be elusive in travelers due to low egg load and the absence of seroconversion upon arrival. There is need for a more sensitive diagnostic test. Therefore, we developed a real-time PCR targeting the Schistosoma haematobium-specific Dra1 sequence.

Methodology/Principal Findings

The PCR was evaluated on urine (n = 111), stool (n = 84) and serum samples (n = 135), and one biopsy from travelers and migrants with confirmed or suspected schistosomiasis. PCR revealed a positive result in 7/7 urine samples, 11/11 stool samples and 1/1 biopsy containing S. haematobium eggs as demonstrated by microscopy and in 22/23 serum samples from patients with a parasitological confirmed S. haematobium infection. S. haematobium DNA was additionally detected by PCR in 7 urine, 3 stool and 5 serum samples of patients suspected of having schistosomiasis without egg excretion in urine and feces. None of these suspected patients demonstrated other parasitic infections except one with Blastocystis hominis and Entamoeba cyst in a fecal sample. The PCR was negative in all stool samples containing S. mansoni eggs (n = 21) and in all serum samples of patients with a microscopically confirmed S. mansoni (n = 22), Ascaris lumbricoides (n = 1), Ancylostomidae (n = 1), Strongyloides stercoralis (n = 1) or Trichuris trichuria infection (n = 1). The PCR demonstrated a high specificity, reproducibility and analytical sensitivity (0.5 eggs per gram of feces).

Conclusion/Significance

The real-time PCR targeting the Dra1 sequence for S. haematobium-specific detection in urine, feces, and particularly serum, is a promising tool to confirm the diagnosis, also during the acute phase of urogenital schistosomiasis.  相似文献   
55.
56.
Motivated by linkage data and the hypothesis that angiogenesis plays a functional role in rheumatoid arthritis (RA), Jacq and colleagues present a family-based, multi-stage, candidate gene association study in French and European Caucasians in a paper on the association of the ITGAV rs3738919-C variant allele with RA (C-containing genotypes: odds ratio 1.94, confidence interval 1.3 to 2.9, P = 0.002). Support comes from a recent genome-wide study, which on its own would have missed identifying the association. Further research into the associating variant will require detailed haplotype analysis, verification in further studies, and research involving intermediate phenotypes or direct functional experiments. This new RA risk factor supports the role of angiogenesis in the disease.  相似文献   
57.
Ohne ZusammenfassungDissertation der Naturwissenschaftlichen Fakultät der Universität Frankfurt (1958). Jetzige Adresse der Verfasserin: Dr.L. Bloss, Tuskegee Institute, Ala. USA.  相似文献   
58.
Oxidation of the reactive site methionine (Met) in α-1-proteinase inhibitor (α-1-PI) to methionine sulfoxide (Met(O)) is known to cause depletion of its elastase inhibitory activity. To estimate the selectivity of different oxidants in converting Met to Met(O) in α-1-PI, we measured the molar ratio Met(O)/α-1-PI at total inactivation. This ratio was determined to be 1.2 for both the myeloperoxidase/H2O2/chloride system and the related compound NH2Cl. With taurine monochloramine, another myeloperoxidase-related oxidant, 1.05 mol Met(O) were generated per mol α-1-PI during inactivation. These oxidants attack preferentially one Met residue in α-1-PI, which is identical with Met 358, as concluded from the parallelism of loss of elastase inhibitory activity and oxidation of Met. A similar high specificity for Met oxidation was determined for the xanthine oxidase-derived oxidants. In contrast, the ratio found for ozone and m-chloroperoxybenzoic acid was 6.0 and 5.0, respectively, indicating oxidation of additional Met residues besides the reactive site Met in α-1-PI, i.e. unselective action of these oxidants. Further studies were performed on the efficiency of oxidants for total depletion of the elastase inhibitory capacity of α-1-PI. Ozone and m-chloroperoxybenzoic acid were 10-fold less effective and the superoxide anion/hydroxyl radicals were 30–50-fold less effective to inactivate the elastase inhibitory activity as compared to the myeloperoxidase-derived oxidants. The myeloperoxidase-related oxidants are discussed as important regulators of α-1-PI activity in vivo.  相似文献   
59.
5 new taxa are described and illustrated; their position within the subgenus is discussed:T. hirta W. Till & L. Hromadnik,T. cotagaitensis L. Hromadnik,T. caliginosa W. Till, andT. gilliesii Baker subsp.polysticha W. Till & L. Hromadnik are members of a group includingT. myosura Grisebach exBaker,T. mandonii E. Morren exMez in DC.,T. retorta Grisebach exBaker em.Grisebach andT. andicola Gillies exBaker. T. brealitoensis L. Hromadnik is related toT. angulosa Mez in DC. but distinct and possibly of hybrid origin.
  相似文献   
60.
The extracellular 373-kDa PehA heme peroxidase of Pseudomonas putida KT2440 has two enzymatic domains which depend on heme cofactor for their peroxidase activity. A null pehA mutant was generated to examine the impact of PehA in rhizosphere colonization competence and the induction of plant systemic resistance (ISR). This mutant was not markedly hampered in colonization efficiency. However, increase in pehA dosage enhanced colonization fitness about 30 fold in the root and 900 fold in the root apex. In vitro assays with purified His-tagged enzymatic domains of PehA indicated that heme-dependent peroxidase activity was required for the enhancement of root tip colonization. Evaluation of live/dead cells confirmed that overexpression of pehA had a positive effect on bacterial cell viability. Following root colonization of rice plants by KT2440 strain, the incidence of rice blast caused by Magnaporthe oryzae was reduced by 65% and the severity of this disease was also diminished in comparison to non-treated plants. An increase in the pehA dosage was also beneficial for the control of rice blast as compared with gene inactivation. The results suggest that PehA helps P. putida to cope with the plant-imposed oxidative stress leading to enhanced colonization ability and concomitant ISR-elicitation.  相似文献   
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