Study of serum levels of superoxide dismutase in preeclampsia and eclampsia: role of the test as a predictive tool

AIM: To report serum levels of superoxide dismutase in women with preeclampsia and eclampsia. To document the use of the value as a predictive tool for deciding the time of onset of subsequent convulsions with fulminating eclampsia and use of the value as a marker for obstetric intervention in clinical severe preeclampsia and eclampsia. METHODS: Superoxide dismutase concentration was measured in a consecutive study in sera of women admitted in obstetric ward for preeclampsia and eclampsia, and compared with sera of normotensive, healthy pregnant women in third trimester. Three mL venous blood was subjected to superoxide dismutase estimation by pyrogallol autoxidation method. RESULTS: We found statistically significant difference (P < 0.05) in mean superoxide dismutase levels of normotensive pregnant women; and preeclamptic and eclamptic subjects, no statistically significant difference was found in between value of enzyme in preeclampsia and eclampsia (P > 0.05). Superoxide dismutase levels in two pregnancy outcomes; live births and still births, shows significant difference (P < 0.05), being 1.03 U/mL and 0.52 U/mL, respectively. The comparison of values before delivery and after delivery showed highly statistically significant difference (P < 0.001) in both groups separately. The cut-off value of serum superoxide dismutase 0.52 U/mL has sensitivity 68.5%, specificity 59.5% and negative predictive value of 78.6%, for predicting the fetal death as outcome of pregnancy with severe grade of disease. CONCLUSION: We found low levels of serum superoxide dismutase, less than 0.52 U/mL, being the predecessor of fulminating eclampsia. Our results support this predictive value of serum superoxide dismutase level as important in deciding the time of intervention as termination of pregnancy.     

Lipid raft microdomains: a gateway for compartmentalized trafficking of Ebola and Marburg viruses

Spatiotemporal aspects of filovirus entry and release are poorly understood. Lipid rafts act as functional platforms for multiple cellular signaling and trafficking processes. Here, we report the compartmentalization of Ebola and Marburg viral proteins within lipid rafts during viral assembly and budding. Filoviruses released from infected cells incorporated raft-associated molecules, suggesting that viral exit occurs at the rafts. Ectopic expression of Ebola matrix protein and glycoprotein supported raft-dependent release of filamentous, virus-like particles (VLPs), strikingly similar to live virus as revealed by electron microscopy. Our findings also revealed that the entry of filoviruses requires functional rafts, identifying rafts as the site of virus attack. The identification of rafts as the gateway for the entry and exit of filoviruses and raft-dependent generation of VLPs have important implications for development of therapeutics and vaccination strategies against infections with Ebola and Marburg viruses.     

Mutational effects on protein folding stability and antigenicity: the case of streptococcal pyrogenic exotoxin A

The influence of mutationally induced changes in protein folding on development of effective neutralizing antibodies during vaccination remains largely unexplored. In this study, we probed how mutational substitutions of streptococcal pyrogenic exotoxin A (SPEA), a model bacterial superantigen, affect native conformational stability and antigenicity. Stability changes for the toxin variants were determined using circular dichroism and fluorescence measurements, and scanning calorimetry. Self-association was assayed by dynamic light scattering. Inactivated SPEA proteins containing particular combinations of mutations elicited antibodies in HLA-DQ8 transgenic mice that neutralized SPEA superantigenicity in vitro, and protected animals from lethal toxin challenge. However, a highly destabilized cysteine-free mutant of SPEA did not provide effective immunity, nor did an irreversibly denatured version of an otherwise effective mutant protein. These results suggest that protein conformation plays a significant role in generating effective neutralizing antibodies to this toxin, and may be an important factor to consider in vaccine design.     

Alveolar distraction: analysis of 10 cases

OBJECTIVE: The purpose of this study was to evaluate intraoperative and postoperative complications of alveolar distraction and outcome. STUDY DESIGN: Ten patients with alveolar ridge deficiencies were treated with alveolar distraction osteogenesis by means of intraosseous distractors (Lead system, Stryker Leibenger, Kalamazoo, Mich). The deficiencies were caused by atrophy after periodontal disease or atrophy after tooth extraction (n = 6), benign tumor resection (n = 2), trauma (n = l), or oligodontia in a case of ectodermal dysplasia (n = l). The location of the defects was the anterior mandible (7), posterior mandible (1), and anterior maxilla (2). The mean follow-up was 1.8 years, with a range of 10 months to 3 years. RESULTS: The mean alveolar distraction achieved in 10 cases was 8.7 mm (5-15 mm). The intraoperative and postoperative problems encountered were lingual (n = 3) and palatal (n = 2) displacement of the distracted segment, fracture of the distracted segment in a very thin alveolar bone (n = 1), and intraoperative bleeding (n = 1). CONCLUSION: Overall complication rate was 70%. However, most of the complications were minor and eliminated easily. Implant success rate was 85%.     

Correlation of body temperature with protection against staphylococcal enterotoxin B exposure and use in determining vaccine dose-schedule

The immunoprotective potential of a recombinant vaccine against the incapacitating effect of aerosolized staphylococcal enterotoxin B (SEB) in nonhuman primates is reported. SEB belongs to a family of structurally related superantigens responsible for serious, life threatening pathologies. Injecting the recombinant SEB vaccine did not induce temperature elevation in rhesus monkeys, a classical symptom of toxic-shock syndrome. No temperature elevation was noted following injection with control tetanus toxoid. In addition to 100% survival, we observed a clear correlation between vaccine dose and mitigation of temperature elevation after a lethal SEB aerosol challenge. We conclude that the recombinant SEB vaccine is non-pyrogenic and that monitoring changes in body temperature is an important biomarker of toxic shock in a primate animal model.