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Haptoglobin and transferrin (TF) types were determined for 134 patients with leukaemia of the four most common types: acute lymphocytic (ALL), chronic lymphocytic (CLL), acute myelocytic (AML) and chronic myelocytic leukaemia (CML). The phenotype HP1 was found to have an increased incidence in the total patient group due to an increased incidence in those with AML, ALL and CML compared with controls, but not in those with CLL. Although tests of association applied to each of the samples of the four common types of leukaemia produced no significant chi 2 values, they did indicate that the relative incidence (RI) was just under 2 for the groupings of the acute forms ALL and AML, the myelocytic forms AML and CML and for the combination of ALL, AML and CML, respectively. All these associations were statistically significant (p less than 0.05). Analysis of TF subtypes and leukaemia indicated a significantly increased frequency of TF C1C1 among leukaemia patients compared with controls (p less than 0.005). Analysis of the samples of each of the four common types suggested that while the RI was raised in all but ALL patients, the association was significant only in AML patients (p less than 0.05). However, when the two myelocytic types were combined the RI was 2.3 and the association was highly significant (p less than 0.005). No such association could be detected in the lymphocytic forms.  相似文献   
3.
Abstract Microbial transformation of N , N -dimethyl- p -phenylene diamine (DMPDA), a microbial product formed from the fungicide fenaminosulf ( p -dimethylaminobenzenediazo sodium sulfonate) was studied by enriching microbes in soils treated with the amine. Microorganisms isolated from DMPDA-treated soil belonged to the genera of Micrococcus, Alcaligenes , and Corynebacterium . Of the various isolates, Alcaligenes DM4 showed maximal growth on DMPDA utilizing it as sources of carbon and nitrogen. When grown in mineral salts basal medium containing 0.05% DMPDA to serve as carbon and nitrogen sources, Alcaligenes DM4 grew exponentially up to 18 h. Even though the characterization of the complete pathway of microbial degradation of DMPDA could not be carried out due to the auto-oxidation of the compound, the initial transformation product of DMPDA by Alcaligenes DM4 has been identified as a dimer. The dimer is generated into the culture medium presumably by the extra-cellular oxidase of Alcaligenes DM4. It is suggested that the risk-benefit evaluation on the use of fenaminosulf is to be made taking into consideration the microbial transformations of the fungicide.  相似文献   
4.
Beta-catenin is linked with colorectal cancer (CRC). Therefore, it is of interest to design and develop novel compounds to combat CRC. Hence, we document compounds (chlorogenic acid, gallic acid, protocatechuic acid, quercetin and vanillic acid) from Lycopersicon esculentum with optimal binding features for further consideration.  相似文献   
5.
A mixture of sphingomyelin (SM) and cholesterol (Chol) exhibits a characteristic lipid raft domain of the cell membranes that provides a platform to which various signal molecules as well as virus and bacterial proteins are recruited. Several proteins capable of specifically binding either SM or Chol have been reported. However, proteins that selectively bind to SM/Chol mixtures are less well characterized. In our screening for proteins specifically binding to SM/Chol liposomes, we identified a novel ortholog of Pleurotus ostreatus, pleurotolysin (Ply)A, from the extract of edible mushroom Pleurotus eryngii, named PlyA2. Enhanced green fluorescent protein (EGFP)-conjugated PlyA2 bound to SM/Chol but not to phosphatidylcholine/Chol liposomes. Cell surface labeling of PlyA2-EGFP was abolished after sphingomyelinase as well as methyl-β-cyclodextrin treatment, removing SM and Chol, respectively, indicating that PlyA2-EGFP specifically binds cell surface SM/Chol rafts. Tryptophan to alanine point mutation of PlyA2 revealed the importance of C-terminal tryptophan residues for SM/Chol binding. Our results indicate that PlyA2-EGFP is a novel protein probe to label SM/Chol lipid domains both in cell and model membranes.  相似文献   
6.
This article demonstrates the use of mixed effects models for characterizing individual and sample average growth curves based on serial anthropometric data. These models are advancement over conventional general linear regression because they effectively handle the hierarchical nature of serial growth data. Using body weight data on 70 infants in the Born in Bradford study, we demonstrate how a mixed effects model provides a better fit than a conventional regression model. Further, we demonstrate how mixed effects models can be used to explore the influence of environmental factors on the sample average growth curve. Analyzing data from 183 infant boys (aged 3–15 months) from rural South India, we show how maternal education shapes infant growth patterns as early as within the first 6 months of life. The presented analyses highlight the utility of mixed effects models for analyzing serial growth data because they allow researchers to simultaneously predict individual curves, estimate sample average curves, and investigate the effects of environmental exposure variables. Am J Phys Anthropol, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
7.
Two-dimensional gas chromatography coupled with time-of-flight mass spectrometry is a powerful tool for identifying and quantifying chemical components in complex mixtures. It is often used to analyze gasoline, jet fuel, diesel, bio-diesel and the organic fraction of bio-crude/bio-oil. In most of those analyses, the first dimension of separation is non-polar, followed by a polar separation. The aqueous fractions of bio-crude and other aqueous samples from biofuels production have been examined with similar column combinations. However, sample preparation techniques such as derivatization, solvent extraction, and solid-phase extraction were necessaryprior to analysis. In this study, aqueous fractions obtained from the hydrothermal liquefaction of algae were characterized by two-dimensional gas chromatography coupled with time-of-flight mass spectrometry without prior sample preparation techniques using a polar separation in the first dimension followed by a non-polar separation in the second. Two-dimensional plots from this analysis were compared with those obtained from the more traditional column configuration. Results from qualitative characterization of the aqueous fractions of algal bio-crude are discussed in detail. The advantages of using a polar separation followed by a non-polar separation for characterization of organics in aqueous samples by two-dimensional gas chromatography coupled with time-of-flight mass spectrometry are highlighted.  相似文献   
8.
Interactions between enamel matrix proteins are important for enamel biomineralization. In recent in situ studies, we showed that the N-terminal proteolytic product of ameloblastin co-localized with amelogenin around the prism boundaries. However, the molecular mechanisms of such interactions are still unclear. Here, in order to determine the interacting domains between amelogenin and ameloblastin, we designed four ameloblastin peptides derived from different regions of the full-length protein (AB1, AB2 and AB3 at N-terminus, and AB6 at C-terminus) and studied their interactions with recombinant amelogenin (rP172), and the tyrosine-rich amelogenin polypeptide (TRAP). A series of amelogenin Trp variants (rP172(W25), rP172(W45) and rP172(W161)) were also used for intrinsic fluorescence spectroscopy. Fluorescence spectra of rP172 titrated with AB3, a peptide encoded by exon 5 of ameloblastin, showed a shift in λmax in a dose-dependent manner, indicating molecular interactions in the region encoded by exon 5 of ameloblastin. Circular dichroism (CD) spectra of amelogenin titrated with AB3 showed that amelogenin was responsible for forming α-helix in the presence of ameloblastin. Fluorescence spectra of amelogenin Trp variants as well as the spectra of TRAP titrated with AB3 showed that the N-terminus of amelogenin is involved in the interaction between ameloblastin and amelogenin. We suggest that macromolecular co-assembly between amelogenin and ameloblastin may play important roles in enamel biomineralization.  相似文献   
9.
Effects of pre-treatment with the alcoholic extract of I. tinctoria (500 mg/kg body wt/day, p.o. for 21 days) on liver antioxidant defense system during acute hepatitis induced by D-galactosamine (D-GalN)/endotoxin (LPS extracted by phenol water method from E. coli serotype 0111.B4; 300 mg and 30 micrograms/kg body wt/day, i.p., 18 hr before the assay) were investigated on the activities of enzymic antioxidants such as superoxide dismutase, catalase, glutathione peroxidase and glutathione-s-transferase, and levels of total reduced glutathione in the liver of normal and experimental groups of male albino rats. Since lipid peroxidation and associated membrane damage is a key feature of D-galN/LPS-induced liver injury, the levels of lipid peroxides, was estimated and used as an index of oxidative stress. D-GalN/endotoxin-induced hepatic damage was manifested by a significant decrease in the activities of antioxidant enzymes, decreased glutathione levels and increased levels of lipid peroxides. I. tinctoria pre-treated rats showed considerable protection against D-galN/endotoxin, induced oxidative stress as evidenced by a significant increase in the activities of all the antioxidant enzymes studied and significant decrease in the levels of lipid peroxides. Results indicate that pretreatment with I. tinctoria extract in rats is very effective in reducing D-GalN/endotoxin-induced oxidative stress suggesting an antioxidant effect.  相似文献   
10.
An in vitro propagation protocol has been developed for Excoecaria agallocha L. (Euphorbiaceae), a mangrove species. Nodal segments were used for axillary shoot proliferation. One shoot from each node of binodal explants was observed 3 weeks after inoculation. The best axillary sprouting was seen on a newly formulated medium containing BA, Zeatin and IBA in concentrations of 13.3 μM, 4.65 μM and 1.23 μM, respectively. The new medium, first used in this study, has a specific composition of major nutrients, MS micronutrients and iron compounds. Nodal segments from rooted cuttings and seedlings responded better than those of mature tree explants. Multiple shoot induction was complemented with efficient shoot elongation, and repeated subculture of binodal segments from axillary shoots resulted in 10–12 shoots per explant in 3 months. Rooting was achieved by growing shoots in the new medium with 0.23 μM IBA. Regenerated plants were successfully acclimatized to the natural environment, and about 85% of plantlets survived under ex vitro conditions. This is the first report of micropropagation in the genus Excoecaria and also in mangrove tree species. Received: 11 August 1997 / Revision received: 10 February 1998 / Accepted: 2 March 1998  相似文献   
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