360 research outputs found
Indications for flexible fiberoptic bronchoscopy and its safety in the very elderly
Aim. To evaluate the indications and the safety of fiberoptic bronchoscopy (FOB) with bronchoalveolar lavage (BAL), protected specimen brushing (PSB), endobronchial biopsy (EBB), and transbronchial biopsy (TBB) in a population of very elderly patients. Methods. We performed a retrospective study of all adult patients, aged 50 years or older, who underwent FOB in the Bronchology Unit of the University of Parma Hospital between 1 January, 2003 and 31 April, 2005. Bronchoscopy records of 436 consecutive patients, including 191 patients, 75 yrs of age and older ("very elderly"; =>75 yrs), were reviewed. Results. Patients aged 75 years were no different with regard to gender, BMI, baseline FEV1/FVC ratio, baseline SaO2, and blood pressure. The primary indication in patients aged <75 years, was to assist in the diagnosis of a pulmonary mass of unknown aetiology (33%) and to remove secretions in the very elderly patients (31%). Indications for FOB and sampling procedures in the two groups were similar. Approximately 30% of patients in each group required supplemental oxygen during the procedure and fever occurred in 9.2% and 10.3% of patients, respectively.Hypertension and bleeding were relatively rare and did not occur more often in the very elderly. Conclusions. Indication for FOB did not vary with age and adverse events in both groups were uncommon and generally not severe
Bacteria causing important diseases of citrus utilise distinct modes of pathogenesis to attack a common host.
The barley a-thionin promotor is rich in negative regulatory motifs and directs tissue-specific expression of a reporter gene in tobacco.
The promoter of the barley α-thionin gene (1.6 kb) fused to the ÎČ-glucuronidase (GUS) gene directs temporally-controled, tissue-specific expression in the endosperm of transgenic tobacco. The nucleotide sequence of this promoter shows negative regulatory motifs which have been functionally analyzed in other gene
Rapid and sensitive detection of Citrus Bacterial Canker by loop-mediated isothermal amplification combined with simple visual evaluation methods
<p>Abstract</p> <p>Background</p> <p>Citrus Bacterial Canker (CBC) is a major, highly contagious disease of citrus plants present in many countries in Asia, Africa and America, but not in the Mediterranean area. There are three types of Citrus Bacterial Canker, named A, B, and C that have different genotypes and posses variation in host range within citrus species. The causative agent for type A CBC is <it>Xanthomonas citri </it>subsp. <it>citri</it>, while <it>Xanthomonas fuscans </it>subsp. <it>aurantifolii</it>, strain B causes type B CBC and <it>Xanthomonas fuscans </it>subsp. <it>aurantifolii </it>strain C causes CBC type C. The early and accurate identification of those bacteria is essential for the protection of the citrus industry. Detection methods based on bacterial isolation, antibodies or polymerase chain reaction (PCR) have been developed previously; however, these approaches may be time consuming, laborious and, in the case of PCR, it requires expensive laboratory equipment. Loop-mediated isothermal amplification (LAMP), which is a novel isothermal DNA amplification technique, is sensitive, specific, fast and requires no specialized laboratory equipment.</p> <p>Results</p> <p>A loop-mediated isothermal amplification assay for the diagnosis of Citrus Bacterial Canker (CBC-LAMP) was developed and evaluated. DNA samples were obtained from infected plants or cultured bacteria. A typical ladder-like pattern on gel electrophoresis was observed in all positive samples in contrast to the negative controls. In addition, amplification products were detected by visual inspection using SYBRGreen and using a lateral flow dipstick, eliminating the need for gel electrophoresis. The sensitivity and specificity of the assay were evaluated in different conditions and using several sample sources which included purified DNA, bacterium culture and infected plant tissue. The sensitivity of the CBC-LAMP was 10 fg of pure <it>Xcc </it>DNA, 5 CFU in culture samples and 18 CFU in samples of infected plant tissue. No cross reaction was observed with DNA of other phytopathogenic bacteria. The assay was capable of detecting CBC-causing strains from several geographical origins and pathotypes.</p> <p>Conclusions</p> <p>The CBC-LAMP technique is a simple, fast, sensitive and specific method for the diagnosis of Citrus Bacterial Canker. This method can be useful in the phytosanitary programs of the citrus industry worldwide.</p
Searching for Molecular Markers for Salt Tolerance in Rhodes Grass (\u3ci\u3eChloris gayana\u3c/i\u3e Kunth)
Rhodes grass (Chloris gayana Kunth), a C4 forage grass, is regarded as salttolerant and exhibits intra- and inter-cultivar variability for this trait. Plants of cv Boma were selected for salt tolerance at the seedling and adult stages, cloned and characterized by RAPD and AFLP amplification patterns. Both techniques were equally efficient for fingerprinting these clones. More bands were obtained by AFLP but the ratio of polymorphic bands and the proportion present only in tolerant clones were the same by both methods. These bands, along with those exclusive for sensitive clones could be useful as markers for assisted selection
The role of vascular endothelial growth factor and matrix metalloproteinases in canine lymphoma: in vivo and in vitro study
Ectopic expression of GmNHX3 and GmNHX1, encoding two Glycine max Na+/H+ vacuolar antiporters, improves water deficit tolerance in Arabidopsis thaliana
The importance of Na+/H+ antiporters in salt tolerance in plants has been demonstrated in many studies, but much less is known about their protective role during drought stress. To study their possible contribution to water deficit tolerance, two closely related soybean Na+/H+ antiporters belonging to the intracellular NHX exchanger protein family, GmNHX3 and GmNHX1, were evaluated in transgenic Arabidopsis thaliana. A. thaliana plants ectopically expressing GmNHX3 or GmNHX1 displayed a more drought-tolerant phenotype compared to wild-type plants, which was accompanied by an increase in relative water content and chlorophyll content during stress conditions. Both GmHNX1 and GmHNX3 transgenic lines accumulated higher amounts of Na+ and K+ cations, showed increased antioxidant enzyme activities and less membrane damage due to lipid peroxidation under water deficit, as compared to non-transformed plants. Furthermore, plants expressing GmNHX3 showed an increased sensitivity to abscisic acid as deduced from stomatal closure and seed germination inhibition studies. Finally, a significant up-regulation of abiotic stress-related genes was observed in both transgenic lines compared to wild-type plants in response to abscisic acid and mannitol treatments. These results demonstrate that GmNHX3 and GmNHX1 antiporters confer protection during drought stress in A. thaliana and hence are potential genetic targets to improve drought tolerance in soybean and other crops
Determinants of postnatal spleen tissue regeneration and organogenesis
Abstract The spleen is an organ that filters the blood and is responsible for generating blood-borne immune responses. It is also an organ with a remarkable capacity to regenerate. Techniques for splenic auto-transplantation have emerged to take advantage of this characteristic and rebuild spleen tissue in individuals undergoing splenectomy. While this procedure has been performed for decades, the underlying mechanisms controlling spleen regeneration have remained elusive. Insights into secondary lymphoid organogenesis and the roles of stromal organiser cells and lymphotoxin signalling in lymph node development have helped reveal similar requirements for spleen regeneration. These factors are now considered in the regulation of embryonic and postnatal spleen formation, and in the establishment of mature white pulp and marginal zone compartments which are essential for spleen-mediated immunity. A greater understanding of the cellular and molecular mechanisms which control spleen development will assist in the design of more precise and efficient tissue grafting methods for spleen regeneration on demand. Regeneration of organs which harbour functional white pulp tissue will also offer novel opportunities for effective immunotherapy against cancer as well as infectious diseases
Characterization and analysis of thionin genes
The general designation of thionins has been proposed for a family of homologous proteins that have been isolated from different tissues in a wide range of plant taxa and have been variously named purothionins, viscotoxins, crambins, etc. (see Garcia-Olmedo et al., 1989). The possible involvement of thionins in plant defense was first suggested, on the basis of their in vitro toxicity to plant pathogens, by Fernandez de Caleya et al., (1972). Those observations had been prompted by earlier reports concerning the antimicrobial properties of these polypeptides (Stuart and Harris, 1942; Balls and Harris, 1944). Work on the thionins, which has been actively pursued over the past half-century, has been recently reviewed in detail (Garcia-Olmedo et al., 1989). For this reason, earlier work will only be partially summarized in the present chapter, which will focus on recent developments concerning thionin genes and their potential role in plant defense mechanisms
Controlled synthesis of the DSF cellâcell signal is required for biofilm formation and virulence in Xanthomonas campestris
Virulence of the black rot pathogen Xanthomonas campestris pv. campestris (Xcc) is regulated by cellâcell signalling involving the diffusible signal factor DSF. Synthesis and perception of DSF require products of genes within the rpf cluster (for regulation of pathogenicity factors). RpfF directs DSF synthesis whereas RpfC and RpfG are involved in DSF perception. Here we have examined the role of the rpf/DSF system in biofilm formation in minimal medium using confocal laser-scanning microscopy of GFP-labelled bacteria. Wild-type Xcc formed microcolonies that developed into a structured biofilm. In contrast, an rpfF mutant (DSF-minus) and an rpfC mutant (DSF overproducer) formed only unstructured arrangements of bacteria. A gumB mutant, defective in xanthan biosynthesis, was also unable to develop the typical wild-type biofilm. Mixed cultures of gumB and rpfF mutants formed a typical biofilm in vitro. In contrast, in mixed cultures the rpfC mutant prevented the formation of the structured biofilm by the wild-type and did not restore wild-type biofilm phenotypes to gumB or rpfF mutants. These effects on structured biofilm formation were correlated with growth and disease development by Xcc strains in Nicotiana benthamiana leaves. These findings suggest that DSF signalling is finely balanced during both biofilm formation and virulence
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