Flow cytometric detection of Mycobacterium avium subsp. paratuberculosis-specific antibodies in experimentally infected and naturally exposed calves.

A desirable test to diagnose infections with Mycobacterium avium subsp. paratuberculosis facilitates identification of infected cattle prior to the state of M. avium subsp. paratuberculosis shedding. This study aimed at adjusting a flow cytometry (FC)-based assay, using intact M. avium subsp. paratuberculosis bacteria as the antigen, for diagnosis of M. avium subsp. paratuberculosis infections in calves. Serum samples were collected from experimentally infected (n = 12) and naturally exposed (n = 32) calves. Samples from five calves from positive dams were analyzed to determine the dynamics of maternal antibodies. Samples from adult cattle with defined infection status served as the standard (18 M. avium subsp. paratuberculosis shedders, 22 M. avium subsp. paratuberculosis free). After preadsorption with Mycobacterium phlei, sera were incubated with M. avium subsp. paratuberculosis and M. avium subsp. avium bacterial suspensions, respectively, followed by the separate detection of bovine IgG, IgG1, IgG2, and IgM attached to the bacterial surface. M. avium subsp. paratuberculosis-specific sample/positive (S/P) ratios were compared to enzyme-linked immunosorbent assay (ELISA) S/P ratios. In adult cattle, the FC assay for IgG1 had a sensitivity of 78% at a specificity of 100%. Maternally acquired antibodies could be detected in calves up to 121 days of life. While all but two sera taken at day 100 ± 10 postnatum from naturally exposed calves tested negative, elevated S/P ratios (IgG and IgG1) became detectable from 44 and 46 weeks postinoculation onwards in two calves infected experimentally. Even with the optimized FC assay, M. avium subsp. paratuberculosis-specific antibodies can only occasionally be detected in infected calves less than 12 months of age. The failure to detect such antibodies apparently reflects the distinct immunobiology of M. avium subsp. paratuberculosis infections rather than methodological constraints.

Risk stratification for subclavian artery angioplasty: is there an increased rate of restenosis after stent implantation?

PURPOSE: To compare long-term patency after balloon angioplasty of stenotic or occluded subclavian arteries with and without adjunctive stenting and to identify independent risk factors for restenosis after balloon angioplasty. METHODS: In a retrospective cohort study, 115 consecutive patients (65 women; mean age 60 years, interquartile range 53-68) who underwent PTA for atherosclerotic subclavian artery obstruction within a 15-year period were included. Among these, 26 (23%) consecutive patients had Palmaz stents routinely implanted since 1996. Follow-up investigation was performed in the year 2000. Patency during the median 44-month follow-up period (interquartile range 18-69 months, minimum 12) was evaluated by oscillography, blood pressure measurement, and color-coded duplex sonography. The predictive value of possible risk factors for restenosis was assessed in a multivariate model controlling for cardiovascular comorbidities and angiographic data. RESULTS: PTA success was achieved in 98 (85%) patients, 72 (81%) of 89 undergoing angioplasty alone and all 26 with stents. Complete occlusion of the vessel and long lesions (> or = 2 cm) correlated with a lower success rate. One-year patency was 76% in unstented arteries and 95% in stented lesions due to better primary technical success, but at 4 years, the patency rates were 59% in arteries with stents and 68% in arteries without. Long lesions, residual stenosis after PTA, and stent implantation were independent predictors for restenosis after successful intervention. CONCLUSIONS: Subclavian arterial stent implantation is associated with better 1-year patency than PTA due to improved technical success, but intermediate and long-term outcomes are less favorable, as instent restenosis frequently occurs.

[The cerebrospinal fluid from healthy pigs and pigs with central nervous system diseases]. / Untersuchung des Liquor cerebrospinalis bei gesunden und zentralnervös erkrankten Schweinen.

CSF samples were taken from 50 healthy pigs of both sexes and cytologically and biochemically examined. With the aid of regression calculations it was investigated, whether deep freezing of CSF samples influences the laboratory results. The parameters glucose, urea, creatinine, total protein, magnesium, anorganic phosphate, AST and AP were in good agreement with the values of the original samples exhibiting only slight variations. Minor age relationship was only seen with respect to the two enzymes LDH and HBDH. A linear relationship was found between values in CSF and in serum of the parameters urea, creatinine, sodium and potassium. CSF examination should include cell count, Pandy's test and bacteriological investigation as well as the determination of the levels of the enzymes LDH and HBDH. The activity of the enzymes AST and ALT increases along with the severity of the tissue damage (meningitis). The specific gravity increases similarly to the total protein level in cases of chronic compression of the spinal cord, and Pandy's test becomes positive. However, CSF glucose levels are partly reduced in animals with central nervous symptoms. The levels of the enzymes AP and CK are often increased in central nervous disturbances, but do not admit drawing a conclusion on the degree of damage.