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There is a need for a rapid bioassay to assess estrogen pollutants in water. This study evaluates the use of Fourier Transform Infrared Imaging Spectroscopy (FT-IRIS) as a screening tool for estrogenic effects on estrogen receptor positive breast cancer cells, MCF-7 cells. FT-IRIS acquired spectra revealed a dose response in the carbohydrate and or serine/tyrosine region in single MCF-7 cells after a 48-hour incubation with 17β-estradiol. This response was found to be comparable to that of a validated E-Screen assay, which utilizes the same cells and is 6 days in duration. These data provide support for further validation of this spectroscopic assay.

The degradation of the mixture of steroid hormones including seven estrogens (17α-estradiol, 17β-estradiol, 17α-dihydroequilin, 17α-ethinyl estradiol, estriol, estrone and equilin) and five progestins (levonorgestrel, gestodene, trimegestrone, medrogestone and progesterone) by ozonation in aqueous solution is investigated. The ozonation process provides high removal (up to 100%) of hormones and estrogenicity in the treated water. Computational methods such as quantum chemistry calculations (QCCs) are applied to interpret the observed results. Quantum chemistry descriptors computed for steroid hormones explain the nature of the reactions and differences in reactivities between estrogen and progestin hormones within the framework of the Density Functional Theory (DFT). Computed molecular descriptors were combined with physical properties to develop qualitative structure activity relationship (QSAR) models (using multiple linear regression algorithm). The developed models have correlation coefficients ( R 2 ) of 0.994 for estrogens and 0.997 for progestins, and could be used to predict the removal efficiencies for similar compounds. The frontier molecular orbitals (the HOMO and the LUMO) have a major impact on the reactivity of steroid hormones. The susceptibility of certain functional groups to ozone and possible reactive sites for all steroids was discussed by Frontier Molecular Orbital approach.

Background Streptococcus pneumoniae is a common respiratory pathogen and a major causative agent of respiratory infections, including otitis media (OM). Pneumococcal biofilms have been demonstrated on biopsies of the middle ear mucosa in children receiving tympanostomy tubes, supporting the hypothesis that chronic OM may involve biofilm development by pathogenic bacteria as part of the infectious process. To better understand pneumococcal biofilm formation six low-passage encapsulated nasopharyngeal isolates of S. pneumoniae were assessed over a six-eight day period in vitro. Results Multiparametric analysis divided the strains into two groups. Those with a high biofilm forming index (BFI) were structurally complex, exhibited greater lectin colocalization and were more resistant to azithromycin. Those with a low BFI developed less extensive biofilms and were more susceptible to azithromycin. dsDNA was present in the S. pneumoniae biofilm matrix in all strains and treatment with DNase I significantly reduced biofilm biomass. Since capsule expression has been hypothesized to be associated with decreased biofilm development, we also examined expression of cpsA, the first gene in the pneumococcal capsule operon. Interestingly, cpsA was downregulated in biofilms in both high and low BFI strains. Conclusion All pneumococcal strains developed biofilms that exhibited extracellular dsDNA in the biofilm matrix, however strains with a high BFI correlated with greater carbohydrate-associated structural complexity and antibiotic resistance. Furthermore, all strains of S. pneumoniae showed downregulation of the cpsA gene during biofilm growth compared to planktonic culture, regardless of BFI ranking, suggesting downregulation of capsule expression occurs generally during adherent growth.

The interactome networks of innate immune molecules operating in the early process of Trypanosoma cruzi infection of human cells are unknown. Here we show that T. cruzi regulates the defensin alpha-1 interactome network and that human defensin alpha-1 plays a fundamental role in the initiation of cellular responses to T. cruzi. We demonstrate that human epithelial cells respond to early infection by up regulating the expression and secretion of defensin alpha-1, which causes trypanosome membrane pore formation and depolarization to inhibit T. cruzi motility, which prevents cellular infection. The pores formed in the flagellar membrane of the invasive trypanosomes cause the detachment of the flagellum from the trypanosome body to abolish trypanosome motility, which is required for trypanosome cell entry. This is the first report elucidating the defensin alpha-1 interactome network and showing that defensin alpha-1 disrupts the T. cruzi flagellum to compromise trypanosome motility and prevent cellular infection. Thus, defensin alpha-1 possesses remarkably distinct modes of activity against protozoan parasites than bacteria and viruses, and its actions may provide insights for the development of new anti-trypanosomal strategies. This work was supported by NIH grants AI080580 and AI007281.

The mechanisms of innate immunity against protozoan parasites that cause significant diseases are very limited. Here we show that human defensin α-1 plays a fundamental role in the initiation of innate immune responses to Trypanosoma cruzi. We demonstrate that human epithelial cells respond to early T. cruzi infection by up-regulating the expression and secretion of defensin α-1, which inhibits T. cruzi motility and prevents cellular infection. Human defensin α-1 inhibits trypomastigote motility of T. cruzi and infection at low micromolar concentrations, and this requires direct association of the defensin α-1 with the invasive trypanosome, which causes membrane depolarization and pore formation in the flagellar membrane. Moreover, defensin α-1 alters the flagellar axonemes, breaks both the flagellar membrane that attaches the flagellum to the trypanosome body and the flagellum thereby restricting trypanosome motility, which is required for trypanosome membrane penetration during cell entry. This is the first report showing that defensin α-1 disrupts the T. cruzi flagellum to compromise trypanosome motility and prevents cellular infection. Thus, defensin α-1 possess remarkably distinct modes of activity against protozoan parasites than bacteria and viruses, and their function may provide insights for the development of new antitrypanosomal strategies (supported by NIH grants AI AI080580 and AI007281)

The duration of immunity following vancella-zoster vaccination in healthy children remains a critical issue. In a 3-year study of 140 OKA/Merck vaccine recipients, duration of immunity was assessed by two measures. The first was persistence of varicellazoster antibody measured by modified fluorescent antibody to membrane antigen test. Thirty-six toddler vaccinees 12 to 24 months of age had sera obtained at 6 weeks, 1 year, and 2 years. Geometric mean titer ± SD at 6 weeks was 57.7 ± 2.9; at 1 year, it was 12.4 ± 3.9; at 2 years, it was 9.9 ± 3.9. Repeated-measures analysis of variance showed a significant overall decrease in antibody titer with time (F = 30.62, P < .001). Post hoc comparisons indicated that the 6-week and 1-year titers were significantly different (P < .001), but the difference between 1 and 2 years was not (P = .138). Clinical reinfections were also examined for 3 years after vaccination. Suspected varicella cases were confirmed by a fourfold or more increase in titer. Of 84 toddlers, 68 were exposed one or more times, and 6 became reinfected. Of 49 siblings, 45 were exposed, and one became reinfected. All 7 children had < 70 vesicles and 6 of 7 were afebrile. No cases of zoster occurred. It is concluded that OKA/Merck varicella-zoster vaccination leads to antibody persistence for 2 years and the few reinfections that do occur are greatly attenuated.

To the Editor.— We regret that in our paper "Renal Ultrasound Evaluation of Urinary Tract Infections in Children" (Pediatrics 1986;78:871-878) we neglected to mention that cinical data on the 64 children in our "first series" had been previously published in Pediatric Infectious Disease (1985;4:656-662). Readers interested in further epidemiologic data on these children should consult the earlier study.