RESUMEN
BACKGROUND: Symmetric dimethylarginine (SDMA) is a methylated arginine derived from intranuclear methylation of l-arginine by protein-arginine methyltransferase and released into circulation after proteolysis. It is primarily eliminated by renal excretion, and its concentration is highly correlated with glomerular filtration rate (GFR) in animals and humans and is an earlier indicator of kidney dysfunction than serum creatinine concentration (sCr). OBJECTIVES: To evaluate and quantify the effects of IV fluid therapy (IF) or intermittent hemodialysis (IH) on renal function in a randomized group of dogs previously diagnosed with International Renal Interest Society (IRIS) stage 4 chronic kidney disease (CKD). ANIMALS: Twenty-four client-owned dogs with naturally occurring CKD. METHODS: Serum from 14 dogs treated by IH and 10 dogs treated with IF was submitted for measurement of sCr and SDMA. Dogs in each treatment group received up to 5 treatment sessions, administered 48 hours apart. RESULTS: Significant differences (P ≤ .05) were seen between treatment groups, but dogs from the IH group were the most affected based on SDMA (P < .001), sCr (P < .001), and blood urea (P < .001) concentrations. Furthermore, for each 10% increase in urea reduction ratio, there was a 6.2 µg/dL decrease in SDMA (P = .002). CONCLUSIONS AND CLINICAL IMPORTANCE: Although SDMA is dialyzable biomarker and despite its removal by IH, SDMA correlates better with renal function than does sCr in dogs with CKD undergoing IF and IH.
Asunto(s)
Arginina/análogos & derivados , Enfermedades de los Perros/sangre , Diálisis Renal/veterinaria , Insuficiencia Renal Crónica/veterinaria , Animales , Arginina/sangre , Perros , Femenino , Masculino , Insuficiencia Renal Crónica/sangreRESUMEN
STUDY DESIGN: A descriptive study of the association between diffuse idiopathic skeletal hyperostosis (DISH) and kyphosis. OBJECTIVE: To investigate the association of DISH with Cobb angle of kyphosis in a large cohort of older subjects from the Health Aging and Body Composition Study. SUMMARY OF BACKGROUND DATA: DISH and thoracic kyphosis are well-defined radiographical findings in spines of older individuals. Characteristics of DISH (ossifications between vertebral segments) reflect changes of spine anatomy and physiology that may be associated with Cobb angle of kyphosis. METHODS: Using data from 1172 subjects aged 70 to 79 years, we measured DISH and Cobb angle of kyphosis from computed tomographic lateral scout scans. Characteristics of participants with and without DISH were assessed using the χ² and t tests. Association between DISH and Cobb angle was analyzed using linear regression. Cobb angle and DISH relationship was assessed at different spine levels (thoracic and lumbar). RESULTS: DISH was identified on computed tomographic scout scan in 152 subjects with 101 cases in only the thoracic spine and 51 in both thoracic and lumbar spine segments. The mean Cobb angle of kyphosis in the analytic sample was 31.3° (standard deviation = 11.2). The presence of DISH was associated with a greater Cobb angle of 9.1° and 95% confidence interval (95% CI) (5.6-12.6) among African Americans and a Cobb angle of 2.9° and 95% CI (0.5-5.2) among Caucasians compared with those with no DISH. DISH in the thoracic spine alone was associated with a greater Cobb angle of 10.6° and 95% CI (6.5-14.7) in African Americans and a Cobb angle of 3.8° and 95% CI (1.0-6.5) in Caucasians compared with those with no DISH. CONCLUSION: DISH is associated with greater Cobb angle of kyphosis, especially when present in the thoracic spine alone. The association of DISH with Cobb angle is stronger within the African American population.
Asunto(s)
Hiperostosis Esquelética Difusa Idiopática/complicaciones , Hiperostosis Esquelética Difusa Idiopática/diagnóstico por imagen , Cifosis/complicaciones , Cifosis/diagnóstico por imagen , Negro o Afroamericano , Anciano , Estudios Transversales , Femenino , Humanos , Hiperostosis Esquelética Difusa Idiopática/etnología , Cifosis/etnología , Vértebras Lumbares/diagnóstico por imagen , Masculino , Radiografía , Vértebras Torácicas/diagnóstico por imagen , Población BlancaRESUMEN
Leifsonia xyli subsp. xyli, the causal agent of ratoon stunting disease in sugarcane, is a xylem-limited, nutritionally fastidious, slow growing, gram-positive coryneform bacterium. Because of the difficulties in growing this bacterium in pure culture, little is known about the molecular mechanisms of pathogenesis. Currently, the genome sequence of L. xyli subsp. xyli is being completed by the Agronomical and Environmental Genomes group from the Organization for Nucleotide Sequencing and Analysis in Brazil. To complement this work, we produced 712 Lxx::Tn4431 transposon mutants and sequenced flanking regions from 383 of these, using a rapid polymerase chain reaction-based approach. Tn4431 insertions appeared to be widespread throughout the L. xyli subsp. xyli genome; however, there were regions that had significantly higher concentrations of insertions. The Tn4431 mutant library was screened for individuals unable to colonize sugarcane, and one noncolonizing mutant was found. The mutant contained a transposon insertion disrupting two open reading frames (ORF), one of which had homology to an integral membrane protein from Mycobacterium leprae. Sequencing of the surrounding regions revealed two operons, pro and cyd, both of which are believed to play roles in disease. Complementation studies were carried out using the noncolonizing Lxx::Tn4431 mutant. The noncolonizing mutant was transformed with a cosmid containing 40 kbp of wild-type sequence, which included the two ORF disrupted in the mutant, and several transformants were subsequently able to colonize sugarcane. However, analysis of each of these transformants, before and after colonization, suggests that they have all undergone various recombinant events, obscuring the roles of these ORF in L. xyli subsp. xyli pathogenesis.