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31.
This study was undertaken to develop a new Gram-staining machine controlled by a micro-controller and to investigate the quality
of slides that were stained in the machine. The machine was designed and produced by the authors. It uses standard 220 V AC.
Staining, washing, and drying periods are controlled by a timer built in the micro-controller. A software was made that contains
a certain algorithm and time intervals for the staining mode. One-hundred and forty smears were prepared fromEscherichia coli, Staphylococcus aureus, Neisseria sp., blood culture, trypticase soy broth, direct pus and sputum smears for comparison studies. Half of the slides in each
group were stained with the machine, the other half by hand and then examined by four different microbiologists. Machine-stained
slides had a higher clarity and less debris than the hand-stained slides (p<0.05). In hand-stained slides, some Gram-positive organisms showed poor Gram-positive staining features (p<0.05). In conclusion, we suggest that Gram staining with the automatic machine increases the staining quality and helps to
decrease the work load in a busy diagnostic laboratory. 相似文献
32.
The Genotoxic Effect of the New Acaricide Etoxazole 总被引:2,自引:1,他引:1
Rencüzogğullari E. Basriİla H. Kayraldiz A. Arslan M. Budak Diler S. Topaktas¸ M. 《Russian Journal of Genetics》2004,40(11):1300-1304
Etoxazole is a member of the diphenyl oxazoline class of insecticide, which was newly developed for use on pome fruits, cotton and strawberries as an acaricide. In the present study, genotoxic effects of acaricide etoxazole (ETX) (miticide/ovicide) were investigated using chromosome aberration (CA) test, sister chromatid exchange (SCE) test, and micronucleus test in human lymphocytes. ETX induced the CAs at all concentrations (5, 10, and 20 g/ml) for 24 h and also induced the CA at the highest concentration (20 g/ml) for 48 h only. The inducing the CAs for 48 h treatment period was dose-dependent. In addition, it induced the SCE at all concentrations and treatment periods in a dose-dependent manner as well. Although ETX decreased the mitotic index (MI) at all concentrations and treatment periods dose-dependently, it did not decrease the replication index (RI) when compared to the negative and solvent controls. In addition, ETX induced the micronucleus at all concentrations except 5 g/ml for 48 h. This inducing was dose-dependent as well. It can be concluded that ETX has a potential genotoxic effects in cultured human peripheral lymphocytes. 相似文献
33.
The Smith-Waterman algorithm for local sequence alignment is one of the most important techniques in computational molecular biology. This ingenious dynamic programming approach was designed to reveal the highly conserved fragments by discarding poorly conserved initial and terminal segments. However, the existing notion of local similarity has a serious flaw: it does not discard poorly conserved intermediate segments. The Smith-Waterman algorithm finds the local alignment with maximal score but it is unable to find local alignment with maximum degree of similarity (e.g. maximal percent of matches). Moreover, there is still no efficient algorithm that answers the following natural question: do two sequences share a (sufficiently long) fragment with more than 70% of similarity? As a result, the local alignment sometimes produces a mosaic of well-conserved fragments artificially connected by poorly-conserved or even unrelated fragments. This may lead to problems in comparison of long genomic sequences and comparative gene prediction as recently pointed out by Zhang et al. (Bioinformatics, 15, 1012-1019, 1999). In this paper we propose a new sequence comparison algorithm (normalized local alignment ) that reports the regions with maximum degree of similarity. The algorithm is based on fractional programming and its running time is O(n2log n). In practice, normalized local alignment is only 3-5 times slower than the standard Smith-Waterman algorithm. 相似文献
34.
CaGE: cardiac gene expression knowledgebase 总被引:4,自引:0,他引:4
Bober M Wiehe K Yung C Onal Suzek T Lin M Baumgartner W Winslow R 《Bioinformatics (Oxford, England)》2002,18(7):1013-1014
CaGE is a Cardiac Gene Expression knowledgebase we have developed to facilitate the analysis of genes important to human cardiac function. CaGE integrates the functionality of the LocusLink database with data from several human cardiac expression libraries, phenotypic data from OMIM and data from large-scale microarray gene expression studies to create a knowledgebase of gene expression in human cardiac tissue. The knowledgebase is fully searchable via the web using several intuitive query interfaces. Results can be displayed in several concise easy to navigate formats. AVAILABILITY: CaGE is located at http://www.cage.wbmei.jhu.edu 相似文献
35.
Four different derivatives of aromatic sulfonamides have been synthesized: 1,2-bis[(4-sulfonamidobenzamide)ethoxy]ethane (SBAM), 1,2-bis[(4-sulfonamidobenzoate)ethoxy]ethane, 1,2-bis[(2,4-dichloro-5-sulfonamidobenzamide)ethoxy]ethane, and 1,2-bis[(2,4-dichloro-5-sulfonamidobenzoate)ethoxy]ethane. SBAM is a most potent inhibitor on ciliary epithelium carbonic anhydrase and is approximately 13 times more active against carbonic anhydrase isoform II than against isoform I. 相似文献
36.
37.
In this study, the antimicrobial effects of monophosphazenes such as SM ipemphos and amphos were examined on bacterial and yeast strains. In addition, the biological effects of these compounds were tested on the lipid level of Saccharomyces cerevisiae and Candida albicans cells. The SM has an antimicrobial effect on the bacterial and yeast strains within the range of 100 and 1500 microg. When the concentration was increased, the inhibition zone expanded on the growth media ( p < 0.01; p < 0.001). The ipemphos did not affect the bacterial and yeast cells in the 100 and 600 microg range. In addition, the amphos did not show an antimicrobial effect on the bacterial cells between 100 and 300 microg or on yeast cells at any of the administered concentrations. In vitro media, the biological effects of these molecules were compared with vitamin E, melatonin and fish oil on the yeast cells. We have found that monophosphazenes have growth effects on the cells in vitro media. The lipid level of S. cerevisiae cells was decreased by 300 microg doses of vitamin E, fish oil, and ipemphos (respectively; p < 0.05, p < 0.01, and p < 0. 001). In addition, the lipid levels of the same yeast cells were depressed by 1000-microg doses in all supplemented groups. However, it was observed that the highest decrease in lipid level of S. cerevisiae cells occurred in the amphos group ( p < 0.001). The lipid levels of the C. albicans cells were significantly reduced ( p < 0.01) by 300 microg of amphos and melatonin. In contrast, the vitamin E and fish oil significantly raised ( p < 0.01; p < 0.001) the lipid level of the same yeast cell, as compared with the control. In addition, the lipid level of these cells was increased by administration of 1000 microg vitamin E, and melatonin ( p < 0.01). In conclusion, while high concentrations of ipemphos and amphos have an antimicrobial effect on bacterial and yeast cells, amphos did not affect the yeast cells. While ipemphos and amphos increased cell growth in media, they reduced the lipid level of C. albicans and S. cerevisiae. In addition, the antioxidants such as vitamin E, melatonin, and fish oils affected the lipid level of yeast cells. 相似文献
38.
Miodownik Saul; Melendez Jose; Carlon Vittoria Arslan; Burda Brian 《Journal of applied physiology》1998,84(6):2177-2182
Themethanol-burning lung model has been used as a technique for generatinga predictable ratio of carbon dioxide production (CO2) to oxygen consumption(O2) or respiratoryquotient (RQ). Although an accurate RQ can be generated, quantitativelypredictable and adjustableO2 andCO2 cannot be generated. Wedescribe a new burner device in which the combustion rate of methanolis always equal to the infusion rate of fuel over an extended range ofO2 concentrations. This permitsthe assembly of a methanol-burning lung model that is usable withO2 concentrations up to 100% and provides continuously adjustable and quantitativeO2 (69-1,525 ml/min)and CO2 (46-1,016ml/min) at a RQ of 0.667. 相似文献
39.
Genetic variants in LEP,LEPR, and MC4R explain 30% of severe obesity in children from a consanguineous population
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40.
Fatih Arslan Joo Y. Hong Vydehi Kanneganti Sei-Kyoung Park Susan W. Liebman 《PLoS genetics》2015,11(1)
Prions are self-perpetuating conformational variants of particular proteins. In yeast, prions cause heritable phenotypic traits. Most known yeast prions contain a glutamine (Q)/asparagine (N)-rich region in their prion domains. [PSI+], the prion form of Sup35, appears de novo at dramatically enhanced rates following transient overproduction of Sup35 in the presence of [PIN+], the prion form of Rnq1. Here, we establish the temporal de novo appearance of Sup35 aggregates during such overexpression in relation to other cellular proteins. Fluorescently-labeled Sup35 initially forms one or a few dots when overexpressed in [PIN+] cells. One of the dots is perivacuolar, colocalizes with the aggregated Rnq1 dot and grows into peripheral rings/lines, some of which also colocalize with Rnq1. Sup35 dots that are not near the vacuole do not always colocalize with Rnq1 and disappear by the time rings start to grow. Bimolecular fluorescence complementation failed to detect any interaction between Sup35-VN and Rnq1-VC in [PSI
+][PIN
+] cells. In contrast, all Sup35 aggregates, whether newly induced or in established [PSI
+], completely colocalize with the molecular chaperones Hsp104, Sis1, Ssa1 and eukaryotic release factor Sup45. In the absence of [PIN+], overexpressed aggregating proteins such as the Q/N-rich Pin4C or the non-Q/N-rich Mod5 can also promote the de novo appearance of [PSI
+]. Similar to Rnq1, overexpressed Pin4C transiently colocalizes with newly appearing Sup35 aggregates. However, no interaction was detected between Mod5 and Sup35 during [PSI+] induction in the absence of [PIN
+]. While the colocalization of Sup35 and aggregates of Rnq1 or Pin4C are consistent with the model that the heterologous aggregates cross-seed the de novo appearance of [PSI
+], the lack of interaction between Mod5 and Sup35 leaves open the possibility of other mechanisms. We also show that Hsp104 is required in the de novo appearance of [PSI+] aggregates in a [PIN
+]-independent pathway. 相似文献