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101.
Bacterial blight (BB), caused by Xanthomonas oryzae pv. oryzae, is a major disease of rice managed largely through the deployment of resistance genes. Xa38, a BB resistance gene identified from Oryza nivara acc. IRGC 81825, was mapped on chromosome 4L in a 38.4-kb region. The closely linked markers for this gene, identified earlier, were simple sequence repeat marker RM17499 and sequence-tagged site markers developed from loci Os04g53060 and Os04g53120. Marker Os04g53060 is dominant while the other two markers show smaller size differences difficult to resolve accurately on agarose gel. Based on gene annotation, three nucleotide binding site?Cleucine-rich repeat genes present in the target region were cloned from O. nivara and sequenced. One of the loci, LOC_Os04g53050, had a 48-base-pair deletion in O. nivara acc. IRGC 81825 compared to the cultivated rice. Primers were designed around the deletion and the resulting marker is codominant and easy to score in agarose gel. The newly designed marker co-segregated with Xa38, amplifying products of 269?bp in O. nivara and 317?bp in cultivated rice. This marker could be more useful for marker-assisted selection than ones reported earlier.  相似文献   
102.

Background

The Notch signaling pathway is an evolutionary conserved signal transduction pathway involved in embryonic patterning and regulation of cell fates during development and self-renewal. Recent studies have demonstrated that this pathway is integral to a complex system of interactions, involving as well other signal transduction pathways, and implicated in distinct human diseases. Delta-like 1 (Dll1) is one of the known ligands of the Notch receptors. The role of the Notch ligands is less well understood. Loss-of-function of Dll1 leads to embryonic lethality, but reduction of Delta-like 1 protein levels has not been studied in adult stage.

Methodology/Principal Findings

Here we present the haploinsufficient phenotype of Dll1 and a missense mutant Dll1 allele (Dll1C413Y). Haploinsufficiency leads to a complex phenotype with several biological processes altered. These alterations reveal the importance of Dll1 mainly in metabolism, energy balance and in immunology. The animals are smaller, lighter, with altered fat to lean ratio and have increased blood pressure and a slight bradycardia. The animals have reduced cholesterol and triglyceride levels in blood. At the immunological level a subtle phenotype is observed due to the effect and fine-tuning of the signaling network at the different levels of differentiation, proliferation and function of lymphocytes. Moreover, the importance of the proteolytic regulation of the Notch signaling network emphasized.

Conclusions/Significance

In conclusion, slight alterations in one player of Notch signaling alter the entire organism, emphasizing the fine-tuning character of this pathway in a high number of processes.  相似文献   
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An improved method for the isolation of normal immunoglobulin E is described. The method is based on the use of an immunoadsorbent formed by the mechanical entrapment of antibodies against a myeloma immunoglobulin E into a lattice of a highly cross-linked macroporous polyacrylamide gel. Normal immunoglobulin E was isolated from an immunoglobulin E-rich serum pool as well as from an individual healthy donor. The isolated immunoglobulin E was contaminated with about 20% of immunoglobulin G. An antiserum against normal immunoglobulin E was prepared by immunizing rabbits with the isolated immunoglobulin E.  相似文献   
106.
The quinacrine mustard fluorescence patterns of the metaphase chromosomes of different tissues of the same plant species were found to be identical. Similar studies of the chromosome regions on human material gave the same result.  相似文献   
107.
Abstract An artificial glycoconjugate containing, as a ligand, the deacylated carbohydrate backbone of a recombinant Chlamydia -specific lipopolysaccharide was used as a solid-phase antigen in ELISA to measure antibodies against chlamydial LPS. The specificity and reproducibility of the assay was shown by using a panel of prototype monoclonal antibodies representing the spectrum of antibodies also occuring in patient sera. These mAbs recognized Chlamydia -specific epitopes [ α 2→8-linked disaccharide of 3-deoxy- d - manno -octulosonic acid (Kdo) or the trisaccharide α Kdo-(2→8)-→Kdo] or those shared between chlamydial and Re-type LPS ( α Kdo, α →4-linked Kdo disacccharide). The assay was used to measure IgG, IgA and IgM antibodies against chlamydial LPS in patients with genital or respiratory tract infections. In comparison to the results obtained with sera from blood donors, it became evident that both types of infection result in significant changes in the profile of LPS antibodies.  相似文献   
108.
Mutations in the X chromosomal tRNA 2′?O?methyltransferase FTSJ1 cause intellectual disability (ID). Although the gene is ubiquitously expressed affected individuals present no consistent clinical features beyond ID. In order to study the pathological mechanism involved in the aetiology of FTSJ1 deficiency-related cognitive impairment, we generated and characterized an Ftsj1 deficient mouse line based on the gene trapped stem cell line RRD143. Apart from an impaired learning capacity these mice presented with several statistically significantly altered features related to behaviour, pain sensing, bone and energy metabolism, the immune and the hormone system as well as gene expression. These findings show that Ftsj1 deficiency in mammals is not phenotypically restricted to the brain but affects various organ systems. Re-examination of ID patients with FTSJ1 mutations from two previously reported families showed that several features observed in the mouse model were recapitulated in some of the patients. Though the clinical spectrum related to Ftsj1 deficiency in mouse and man is variable, we suggest that an increased pain threshold may be more common in patients with FTSJ1 deficiency. Our findings demonstrate novel roles for Ftsj1 in maintaining proper cellular and tissue functions in a mammalian organism.  相似文献   
109.
Ochratoxin A (OTA) is a mycotoxin mainly produced by a number of species of Aspergillus, commonly found in warm and tropical climates. OTA poses risks for the human health because of its nephrotoxic, teratogenic, immunotoxic and neurotoxic activity. The mycotoxin, classified as possible human carcinogen (Group 2B) by the IARC, naturally occurs in a wide range of foods, including wine, where the main producer is A. carbonarius. The aim of this work was the validation of a procedure for the analysis of OTA in Piedmontese red and white wines produced after vintage 2003 and 2004, in relationship with the limit of 2.0 microg l(-1) introduced by European Union for wine, must or grape juice (Regulation CE N. 123/2005). An analytical method based on immunoaffinity column (IAC) for clean-up and liquid chromatography with fluorescence detection (LC-FLD) was used to determine the occurrence of OTA in wines. Detection limit (LOD) and quantification Limit (LOQ) were 7.18 pg/ml and 9.31 pg/ml based on statistical method (IUPAC). Average recoveries of OTA from wine samples spiked at levels from 0.1 to 10 ng/ml ranged from 90.8% to 92.4%, with relative standard deviations (RSDs) between 2.64 and 2.71%. Repeatability limit was 8.73 pg/ml for samples spiked with 0.1 ng/ml of OTA. Ninety-one Denomination of Controlled Origin (DOC) wines were analysed, including 41 Barbera (red), 38 Dolcetto (red), and 16 white wines, such as Erbaluce, Cortese and Roero Arneis. The study focused on wines commercialized in Italian supermarkets and wine shops. The white wines resulted, as expected, less contaminated than the red ones. Wines produced after vintage 2003, a season particularly conducive to the growth of A. carbonorius, contained higher levels of OTA than the wines produced in 2004. The samples, resulting positive, contained a concentration of OTA highly inferior to the threshold limits introduced by the European Union. The sample of the highest level of OTA was a Dolcetto produced in 2004, with 1.10 ng/ml of mycotoxin.  相似文献   
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