Use and comparison of serologic assays to detect anti-Neospora caninum antibodies in farmed red deer (Cervus elaphus).

Neospora caninum is a protozoan parasite that cause abortion in different ruminant species, including red deer ( Cervus elaphus). There are no validated assays to be performed with sera from red deer. At the present work, we evaluated the agreement among indirect fluorescent antibody test (IFAT), competitive inhibition ELISA based on a recombinant protein (ciELISA tSAG1) and immunoblot (IB) to detect anti- N. caninum antibodies in a red deer herd that presented reproductive losses due to N. caninum. In addition, we analyzed the relationship between the serologic results and 15 hinds were analyzed by IFAT, ciELISA tSAG1 and IB to detect anti- N. caninum antibodies. In the three assays, the cut-off established for cattle was used. Besides, sera were analyzed by IFAT to detect anti- Toxoplasma gondii antibodies. The hinds were monitored by ultrasound scanning during the gestational period to detect abortions. Gwet's agreement coefficient (AC1) and the percentage of agreement were used to estimate the agreement between pairs of assays. Chi-square test and odds ratio (OR) were used for the statistical association between abortion and seropositivity to N. caninum or to T. gondii. The N. caninum seropositivity rate was 53.9% (62/115), 57.4% (66/115) and 55.7% (64/115) for IFAT, ciELISA tSAG1 and IB, respectively. The AC1 and percentage of agreement were 0.760% and 87.8% for the pair ciELISA tSAG1 /IFAT, 0.793% and 89.6% for the pair IFAT/IB, and 0.966% and 98.3% for the pair IB/ciELISA tSAG1. The T. gondii seropositivity rate was 53.0% (61/115). Seropositive hinds to N. caninum were more likely to abort than seronegative hinds by the 3 assays. The OR for the association between N. caninum seropositivity and abortion was 72.70, 22.96 and 83.24 when ciELISA tSAG1, IFAT or IB assays were used, respectively. between T. gondii seropositivity and abortion. The three serologic assays were useful to detect N. caninum infected hinds. The validation of the assays for use in red deer would be an improvement for diagnosis of neosporosis in this species.

Engineered variants of human glutamic acid decarboxylase (GAD) and autoantibody epitope recognition.

Of the two homologous forms of glutamic acid decarboxylase, GAD65 and GAD67, only GAD65 is a common target of autoimmunity. Epitope profiles of autoantibodies to GAD65 (GADA) in 140 type 1 diabetes, adult-onset diabetes mellitus (AODM), and thyroid diseases (TD) were studied. Probes were GAD65, GAD65/67 hybrids (displaying separately GAD65 residues 1-95, 96-444, and 445-585), delta GAD65 (a truncated GAD65 spanning residues 69-585), and GAD67. delta GAD65 and GAD65 detected 137 and 125 positive patients, respectively. The hybrids reacted with 113 sera and in 3 cases disclosed cryptic epitopes. Eighteen patients reacted with GAD67, indicating GAD65-GAD67 cross-reactivity. Most patients recognized both middle and C-terminal epitopes, had low reactivity against N-terminal epitopes, and seldom displayed reactivity limited to the N or C terminus. Compared with type 1 and AODM, TD patients showed a greater prevalence of multiple reactivity and higher incidence of GAD67 positivity.

[Accuracy of an the ear oximeter Biox-III and its sensitivity to carboxyhemoglobin in Mexico City]. / Exactitud del oxímetro de oído (Biox-III) en la ciudad de México y su sensibilidad a la carboxihemoglobina.

Ear oximeters estimate arterial oxygen saturation (Sa02) measuring the characteristics of light transmission through the ear lobe. We tested the accuracy of a new ear oximeter (Biox-III) in Mexico City comparing its estimates (Sa02OXI) with Sa02 measured by a Co-Oximeter, in a simultaneously taken arterial blood sample. We used two indexes in the arterial sample: Sa02 of the total hemoglobin (Sa02T) given directly by the Co-Oximeter and Sa02 of the hemoglobin available for oxygenation (Sa02A) which corrects for the presence of carboxyhemoglobin and metahemoglobin. We studied 21 subjects with a total of 100 simultaneous samples with a Sa02T ranging from 36.2% to 97.2%. The samples were obtained with the subjects resting, during light exercise, during rebreathing and increasing the Fi02. Spearman and Pearson's correlation coefficients between Sa02OXI and Sa02A were 0.97, and between Sa02OXI and Sa02T were 0.96. Lineal regression equations were: Sa02T = 2.047 (Sa02OXI) -8.5 and Sa02A = 1.102 (Sa02OXI) -9.32. Slopes of the equations and correlation coefficients were statistically significant (P less than 0.001). Mean error of Sa02OXI compared with Sa02T (Sa02T-Sa02OXI) was -4.4% and compared with Sa02A (Sa02A-Sa02OXI) was -0.4%, with a standard deviation of 3.4% and 3.5% respectively. In the presence of carboxyhemoglobin the ear oximeter overestimates Sa02T but not Sa02A. Measurement error increases during rebreathing maybe because error increases at low Sa02 and because of the delay in oximeter's response in a situation of a continuously falling Sa02. Ear oximeter Biox-III estimates Sa02 in Mexico City as accurately as the Biox-IIA at sea level. Sa02 measurement is quick, easy, continuous and non-invasive, which increase its potential clinical and research application.