Seroepidemiology of Toxoplasma gondii infection in women of child-bearing age in central Ethiopia.

BACKGROUND: Toxoplasma gondii infections during pregnancy can result in abortion or congenital defects. Prevalence and risk factors of toxoplasmosis in women of child-bearing age in Ethiopia are unknown. The current study was conducted with the objectives of estimating the seroprevalence and potential risk factors in acquiring T. gondii infection by women of child-bearing age in Central Ethiopia. METHODS: A cross-sectional study was conducted from March 2011 to September 2011. Sera of 425 women were analyzed by indirect enzyme linked immunosorbent assay (ELISA). A questionnaire survey was administered for all study participants to gather information on risk factors. RESULTS: The study revealed that anti- T. gondii IgG antibodies were detected in 81.4% of the samples of which 78.4% were positive for only IgG and 3.06% positive for both IgG and IgM antibodies. Seroprevalence of IgM antibodies to T. gondii (4.0%, 95% CI: 2.14, 5.86) was suggestive of recent infections. Of the 213 pregnant women 9 (4.2 %) were IgM reactive. Out of 17 potential risk factors investigated, univariate logistic regression showed significant association of T. gondii infection with study area, age, pregnancy status, raw vegetable consumption, source of water, presence of cats at home, contact with cats, HIV status and precaution during cats' feces cleaning (P ≤ 0.05). The final logistic regression model revealed that: the probability of acquiring T. gondii infection by women of Debre-Zeit was 4.46 times (95% CI of adjusted odds ratio [aOR]: 1.67, 11.89; P =0.003) higher compared to women of Ambo, pregnant women were twice (95% CI aOR: 1.13, 3.59; P = 0.018) more likely to be seropositive than non-pregnant women and women who consume raw vegetable were at increased risk of infection (aOR = 2.21, 95% CI: 1.03, 4.78; P = 0.043) than women who didn't consume. CONCLUSION: The seroprevalence of T. gondii infection in women of child-bearing age in Central Ethiopia is high. Study area, pregnancy and raw vegetable consumption are risk factors to acquire T. gondii infection. Educational program, antenatal screening of pregnant women and further epidemiological studies to uncover the economic and health impact of toxoplasmosis are suggested.

HU content and dynamics in Escherichia coli during the cell cycle and at different growth rates.

DNA-binding proteins play an important role in maintaining bacterial chromosome structure and functions. Heat-unstable (HU) histone-like protein is one of the most abundant of these proteins and participates in all major chromosome-related activities. Owing to its low sequence specificity, HU fusions with fluorescent proteins were used for general staining of the nucleoid, aiming to reveal its morphology and dynamics. We have exploited a single chromosomal copy of hupA-egfp fusion under the native promoter and used quantitative microscopy imaging to investigate the amount and dynamics of HUα in Escherichia coli cells. We found that in steady-state growing populations the cellular HUα content is proportional to the cell size, whereas its concentration is size independent. Single-cell live microscopy imaging confirmed that the amount of HUα exponentially increases during the cell cycle, but its concentration is maintained constant. This supports the existence of an auto-regulatory mechanism underlying the HUα cellular level, in addition to reflecting the gene copy number. Both the HUα amount and concentration strongly increase with the cell growth rate in different culture media. Unexpectedly, the HU/DNA stoichiometry also remarkably increases with the growth rate. This last finding may be attributed to a higher requirement for maintaining the chromosome structure in nucleoids with higher complexity.