A Combined Strategy to Improve the Development of a Coral Antivenom Against Micrurus spp

Accidents involving Micrurus snakes are not the most common ones but are noteworthy due to their severity. Victims envenomed by Micrurus snakes are at high risk of death and therefore must be treated with coral antivenom. In Brazil, the immunization mixture used to fabricate coral antivenom contains Micrurus frontalis and Micrurus corallinus venoms, which are difficult to be obtained in adequate amounts. Different approaches to solve the venom limitation problem have been attempted, including the use of synthetic and recombinant antigens as substitutes. The present work proposes a combined immunization protocol, using priming doses of M. frontalis venom and booster doses of synthetic B-cell epitopes derived from M. corallinus toxins (four three-finger toxins-3FTX; and one phospholipase A₂-PLA₂) to obtain coral antivenom in a rabbit model. Immunized animals elicited a humoral response against both M. frontalis and M. corallinus venoms, as detected by sera reactivity in ELISA and Western Blot. Relevant cross-reactivity of the obtained sera with other Micrurus species (Micrurus altirostris, Micrurus lemniscatus, Micrurus spixii, Micrurus surinamensis) venoms was also observed. The elicited antibodies were able to neutralize PLA₂ activity of both M. frontalis and M. corallinus venoms. In vivo, immunized rabbit sera completely protected mice from a challenge with 1.5 median lethal dose (LD₅₀) of M. corallinus venom and 50% of mice challenged with 1.5 LD₅₀ of M. frontalis venom. These results show that this combined protocol may be a suitable alternative to reduce the amount of venom used in coral antivenom production in Brazil.

Osteoporotic alterations in a group of different ethnicity Brazilian postmenopausal women: An observational study

OBJECTIVES

To compare peripheral bone mineral density alterations among Brazilian postmenopausal women from three ethnic groups considering age and body mass index influence; to correlate their bone mineral density with the mandibular cortical index (MCI); and to evaluate the influence of age, body mass index and ethnicity in the MCI using risk factor analysis.

BACKGROUND

Osteoporosis risk is known to have ethical influences. However, little is known about the differences in ethnicity in radiomorphometric indices.

MATERIALS AND METHODS

A total of 150 postmenopausal women with different ethnicities (Caucasian, Asian and Afro-descendant) who underwent peripheral dual X-ray absorptiometry and panoramic examination were included. Bone mineral density and MCI were assessed. Adjusted odds ratio analyses were performed on bone density and MCI considering the effect of age, ethnicity and body mass index. The correlations between the MCI and the dual X-ray absorptiometry results were made.

RESULTS

Old age, low body mass index and non-Afro-descendant were associated with low bone density. Compared with Afro-descendants, Asians and Caucasians have higher chances of having decreased bone mass. For the MCI, statistical analysis showed that age is the only variable associated with osteoporotic alterations in the mandible. Furthermore, an inverse correlation was found between the MCI and the T-scores.

CONCLUSION

Bone density is higher in Brazilian Afro-descendant women than in Caucasians and Asians. Patient's age is associated with bone density and the MCI. The mandibular cortical index is inversely correlated with the peripheral densitometry results within the study ethnic population.