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Background and Purpose-Prognostic significance of low-density lipoprotein cholesterol (LDL-C) in intracranial hemorrhage (ICH) is unclear. The objective of this study was to determine the association between LDL-C and mortality in ICH. Methods-Consecutive patients (nϭ88) presenting with ICH were included in the study. Lipid profile was obtained during the first hours after admission. We analyzed the impact of LDL-C on 90-day mortality using the Hazard Rate (HR) crude, analysis crude for trend by Mantel-Haenszel Test, Multiple Cox Proportional Hazards model, and analysis of survival curves. Association between LDL-C and severity markers of ICH were explored using Spearman correlation coefficient. Results-Low LDL-C levels were independently associated with death after intracranial hemorrhage (HRϭ3.07 (95% CI:1.04 to 9.02; Pϭ0.042) in multivariable analysis after controlling for confounding factors. Analysis for trend showed a significant association (XtϭϪ2.144; Pϭ0.032) by Mantel-Haenszel Test. Spearman analysis showed no correlation between LDL-C and variables that are markers of ICH severity: NIH score (rϭϪ0.091; Pϭ0.400), GCS score (rϭ0.136; Pϭ0.207), ICH volume (rϭ0.140; Pϭ0.192), and length of stay (rϭϪ0.111; Pϭ0.308). Conclusions-Low levels of LDL-C are independently associated with an increased risk of death in patients with brain hemorrhage. We have not found evidences that the levels of LDL-C can act as a biological marker of severity.

Babesia bovis msa-1 and msa-2c genes belong to the variable merozoite surface antigen gene family. These genes code for antigenic proteins present on the merozoite surface (MSA) and are involved in the parasite invasion to the bovine erythrocyte. Previous studies carried out on MSA-1 have evidenced antigen allelic variation in B. bovis isolates from similar endemic regions, as well as in isolates from different geographic regions of the world (Argentina, Australia, Israel). Studies conducted on MSA-2c, however, have shown that this antigen is widely conserved on isolates from distinct geographic regions. In this study, it was hypothesized that MSA-1 and MSA-2c antigens would contain common epitopes despite the presence of nucleotide sequence differences found in 13 B. bovis isolates and strains collected in geographically distant regions of Mexico. Bioinformatics analysis of the primary structure from DNA fragments derived from PCR amplification, cloning, and sequencing of msa-1 and msa-2c genes from the 13 B. bovis populations revealed that the msa-1 gene product present in the various isolates tested is less conserved among isolates obtained within a similar geographic region in Mexico (51-99.7% sequence identity). Results obtained by immunoblot analysis of B. bovis protein extracts reacted with a monoclonal antibody to MSA-1 42-kDa antigen, conclusively showed cross-reactive common epitopes only in Mexican isolates having high sequence identity (>/=99%, eight isolates). Sequence analysis and multiple alignment of deduced MSA-2c demonstrated a high degree of sequence identity (90-100%) among the Mexican B. bovis isolates and strains. Immunoblot results using a polyclonal antibody to MSA-2c reacted against the protein extracts recognized conserved epitopes in at least nine of the B. bovis isolates. The results obtained in this study agree with those previously reported by other researchers and confirm that, based in sequence identity conservation in Mexican B. bovis isolates and strains so far collected and analyzed, MSA-2c represents an ideal antigen worth evaluating as a vaccine candidate.

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Variable merozoite surface antigens of Babesia bovis are exposed glycoproteins having a role in erythrocyte invasion. Members of this gene family include msa-1 and msa-2 (msa-2c, msa-2a(1), msa-2a(2), and msa-2b). Small subunit ribosomal (ssr)RNA gene is subject to evolutive pressure and has been used in phylogenetic studies. To determine the phylogenetic relationship among B. bovis Mexican isolates using different genetic markers, PCR amplicons, corresponding to msa-1, msa-2c, msa-2b, and ssrRNA genes, were cloned and plasmids carrying the corresponding inserts were sequenced. Comparative analysis of nucleotide and deduced amino acid sequences revealed distinct degrees of variability and identity among the coding gene sequences obtained from 12 geographically different B. bovis isolates and a reference strain. Overall sequence identities of 47.7%, 72.3%, 87.7%, and 94% were determined for msa-1, msa-2b, msa-2c, and ssrRNA, respectively. A robust phylogenetic tree was obtained with msa-2b sequences. The phylogenetic analysis suggests that Mexican B. bovis isolates group in clades not concordant with the Mexican geography. However, the Mexican isolates group together in an American clade separated from the Australian clade. Sequence heterogeneity in msa-1, msa-2b, and msa-2c coding regions of Mexican B. bovis isolates present in different geographical regions can be a result of either differential evolutive pressure or cattle movement from commercial trade.