Cassava bacterial blight, caused by Xanthomonas axonopodis pv. manihotis (Xam), is the most important bacterial disease affecting this crop. A continuous surveillance of the pathogen population dynamics is required to develop an efficient disease management program. During the 1990s, Xam populations showed high levels of genetic variation and relevant migratory processes that were important determinants of the distribution of the pathogen diversity in Colombia. Aiming to characterize the current population structure of the pathogen and the evolutionary forces that shape these populations, sampling collections were carried out from September 2008 until November 2010 in the Colombian Caribbean Region. One hundred and sixty bacterial isolates were characterized using amplified fragment length polymorphism (AFLP) markers. Additionally, a subset of effector genes were sequenced in some isolates to determine their usefulness in Xam population studies and to provide additional information to that obtained with AFLPs. Virulence patterns of ten isolates were determined in nine cassava accessions. Our results show a complex architecture of population and confirm migratory process previously reported in the Caribbean Region. Chinú, one of the locations sampled, presented remarkable features in population dynamics such as longer genetic distances, higher diversity indices, and a genetically differentiated population when it was compared with other locations. Virulence tests showed that MCOL2215, one of the most cultivated cassava varieties in the Caribbean coast, was susceptible to the majority of Xam isolates tested. This study shows the current condition of populations of Xam in the Caribbean Region of Colombia, and it contributes to improve the existing bacterial blight control practices.
The authors present their experience in the medical treatment of 1, 296 caustic esophageal injuries in children over the last 20 years in two study groups, one comprising the period up to 1989 and the other 1990 to 1996, comparing the different treatments used in each group. The treatment was based fundamentally on dilatations with anterograde mercury bougies, Savary bougies, or retrograde thread-guided bougies with gastrostomy. Pneumatic balloons or stenting procedures have also been employed in the last 3 years. Early fiberendoscopy was used systematically in the second group, which provides a more accurate evaluation of the esophageal lesions. Antibiotic coverage was done systematically during the first 10 days in all serious cases, while steroids were employed routinely only in the last 3 years. The results were similar in both groups, with a dilatation average of 32 in the first and 30 in the second group and an initial dilatation interval of 3 to 4 weeks in both. Using updated exploration and dilatation techniques, we drastically reduced the number of gastrostomies needed for retrograde thread-guided dilatations from 51 in the first group to 5 in the second, consequently improving the patients' life quality. There was no mortality and only five esophageal perforations, which did not require surgical treatment.
Our results support the hypothesis that the component of fecal continence mediated by contraction of the external sphincter depends on a anal external sphincter continence reflex without involving the brain. Presumably, the afferent receptors of this reflex are contact receptors located superficially in the mucosa or submucosa of the distal anal canal. A nonfunctioning anal external sphincter continence reflex would, therefore, result in fecal incontinence (see Video, Supplemental Digital Content 1, http://links.lww.com/DCR/A116).
In this study, we showed that recently diagnosed hypertensive patients have coronary endothelial dysfunction and vasomotor disturbances which are early signs for the development of CAD.
Systemic lupus erythematosus (SLE) affects multiple organs and systems, severely involving the cardiovascular system. The aim of this study was to evaluate the presence of endothelial dysfunction with 13 N-ammonia PET in asymptomatic SLE patients. Methods: We enrolled 16 women with SLE and 16 healthy women. Myocardial blood flow (MBF) was quantified in a 64-slice PET/CT scanner at rest, during a cold pressor test (CPT), and during stress. Endothelium-dependent vasodilation index, %DMBF, and myocardial flow reserve (MFR) were calculated. Results: There were 16 women in the SLE group (mean age 6 SD, 31.4 6 8.3 y) and 16 women in the healthy control group (31.5 6 11.1 y). Mean endothelium-dependent vasodilatation index and %DMBF were significantly lower in SLE patients (1.18 6 0.55 vs. 1.63 6 0.65, P 5 0.04, and 18 6 55 vs. 63 6 65, P 5 0.04, respectively). MFR was also lower in the SLE group (2.41 6 0.59 vs. 2.73 6 0.77, P 5 0.20). Conclusion: SLE patients who are free of active disease present abnormal coronary flow and endothelial dysfunction. It is necessary to develop and intensify treatment strategies directed to CAD in SLE patients.
<p>Oil palm (<em>Elaeis guineensis </em>Jacq.) fruits are classified by shell thickness into three types: <em>dura, pisifera</em>, and <em>tenera</em>, the last one being the product of a <em>dura</em> × <em>pisifera</em> cross. The palm oil industry relies on the use of high-yield <em>tenera</em> plant material for production; however, it is usually generated with female infertile <em>pisifera, </em>so early identification of this trait is very important to oil production and breeding programs. Recently, the mapping and sequencing of the <em>SHELL</em> gene, which is responsible for endocarp formation in oil palms, made it possible to identify two mutations (type SNP, single nucleotide polymorphism) that affect its function and that are useful to developing molecular markers for predicting shell thickness. The aim of this study was to standardize PCR-based methodologies in order to detect the SNP observed in codon 30 and validate it under our <em>E. guineensis</em> biological collections. We achieved the differentiation of SHELL alleles with both allele specific PCR and CAPS with the restriction enzyme <em>Hin</em>dIII in homozygous and heterozygous plants that contained the described mutation, and the prediction was correlated with the phenotype observed in oil palm fruits. These methodologies facilitated the discrimination of plants by fruit type in nursery and pre-nursery stages 24 months before production started, thereby reducing the time and area used in oil palm breeding programs.</p>
The overexpression of RXam1 leads to a reduction in bacterial growth of XamCIO136, suggesting that RXam1 might be implicated in strain-specific resistance. Cassava bacterial blight (CBB) caused by Xanthomonas axonopodis pv. manihotis (Xam) is a prevalent disease in all regions, where cassava is cultivated. CBB is a foliar and vascular disease usually controlled through host resistance. Previous studies have found QTLs explaining resistance to several Xam strains. Interestingly, one QTL called XM5 that explained 13% of resistance to XamCIO136 was associated with a similar fragment of the rice Xa21-resistance gene called PCR250. In this study, we aimed to further identify and characterize this fragment and its role in resistance to CBB. Screening and hybridization of a BAC library using the molecular marker PCR250 as a probe led to the identification of a receptor-like kinase similar to Xa21 and were called RXam1 (Resistance to Xam 1). Here, we report the functional characterization of susceptible cassava plants overexpressing RXam1. Our results indicated that the overexpression of RXam1 leads to a reduction in bacterial growth of XamCIO136. This suggests that RXAM1 might be implicated in strain-specific resistance to XamCIO136.
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