Effects of phytoestrogen extracts isolated from flax on hormone production of trophoblast tumour cells Jeg 3 and BeWo.

UNLABELLED: AIM AND SETTING: To test the effects of crude extracts from flax (Linum usitatissimum) on progesterone and estradiol and ERα and ß/PR production in choriocarcinoma cell lines Jeg 3 and BeWo. Tumor trophoblast cells (Jeg 3 and BeWo) were incubated in the presence of different concentrations of the flax crude extracts. Estradiol and progesterone production was measured. Estrogen receptor α and ß as well as progesterone receptor expressions were also assessed. RESULTS: In Jeg 3 cells, progesterone production was downregulated by flax root and leaves extract, while in BeWo cells only flax root extract did manage to downregulate progesterone production. ERß expression was significantly downregulated by flax root and flax leaves extract in both cell lines; on the contrary, ERα expression was increased by flax leaves extract in BeWo cells. PR expression was downregulated by flax leaves extract in Jeg 3 and by flax root extract in BeWo cells. CONCLUSION: Flax extracts derived from leaves and especially from roots can modify progesterone and possibly estradiol production, while at the same time they seem to alter ERß expression. Further studies on animal models and adequately designed retrospective epidemiological studies are imperative to clarify this role upon progesterone.

Effects of phytoestrogen extracts isolated from flax on estradiol production and ER/PR expression in MCF7 breast cancer cells.

BACKGROUND: In this study, we tested the effects of crude extracts from flax (Linum usitatissimum) on the production of estradiol and expression of estrogen receptor (ER) and progesterone receptor (PR) in human breast cancer MCF7 cells. MATERIALS AND METHODS: Isoflavone and lignan extracts from flax plant Linum usitatissimum were obtained, using different extraction methods. Breast carcinoma cells (MCF7) were incubated with various concentrations of the isolated extracts. Untreated MCF7 cells were used as controls. Supernatants were removed at designated times and tested for estradiol with an ELISA method. Furthermore, the effect of phytoestrogen extracts on the production of ERa and ERbeta as well as on PR was examined. RESULTS AND CONCLUSION: Production of estradiol is elevated in MCF7 cells in a concentration-dependent manner after stimulation with isoflavone and lignan extracts from Linum usitatissimum. Expression of ERalpha is up-regulated after stimulation with lower concentrations of lignan extracts from flax plants, unchanged at median concentrations and down-regulated at high concentrations. Expression of ERbeta is down-regulated in a concentration-dependent manner.

Probe selection algorithms with applications in the analysis of microbial communities.

We propose two efficient heuristics for minimizing the number of oligonucleotide probes needed for analyzing populations of ribosomal RNA gene (rDNA) clones by hybridization experiments on DNA microarrays. Such analyses have applications in the study of microbial communities. Unlike in the classical SBH (sequencing by hybridization) procedure, where multiple probes are on a DNA chip, in our applications we perform a series of experiments, each one consisting of applying a single probe to a DNA microarray containing a large sample of rDNA sequences from the studied population. The overall cost of the analysis is thus roughly proportional to the number of experiments, underscoring the need for minimizing the number of probes. Our algorithms are based on two well-known optimization techniques, i.e. simulated annealing and Lagrangian relaxation, and our preliminary tests demonstrate that both algorithms are able to find satisfactory probe sets for real rDNA data.

Ophthalmologic findings in acquired immune deficiency syndrome (AIDS).

Forty-one homosexually active men had ophthalmologic and immunologic evaluations. Four of eight with acquired immune deficiency syndrome (AIDS) had abnormal ocular findings that included cotton-wool spots, retinal hemorrhages, cytomegalovirus, retinitis and conjunctivitis due to cytomegalovirus, and keratoconjunctivitis sicca. The other four patients with AIDS and 33 homosexual male controls had normal ocular examinations. Patients with AIDS and abnormal eye findings had a notably lower total leukocyte count, absolute lymphocyte count, percentage T-helper lymphocytes, helper-suppressor lymphocyte ratio, hematocrit level, and platelet count than patients with AIDS and normal results on eye examination or controls. All patients with AIDS and abnormal eye examination results died; the four other patients with AIDS and normal eye findings remain alive. These observations suggest that ophthalmologic abnormalities are common in patients with AIDS, are associated with severe immunoregulatory abnormalities, and carry a poor prognosis.

Photic maculopathy secondary to short-circuiting of a high-tension electric current.

A 21-year-old man was exposed accidentally to the flash of a high-tension short circuit. He subsequently developed a yellow-gray foveolar lesion with mild central visual loss. Fluorescein angiography demonstrated the area of retinal pigment epithelial disruption and was used to follow its evolution over eight months. The energy level at the retina was estimated at 0.87 Joules/cm2, insufficient to create a thermal burn. Therefore, although the patient suffered thermal facial burns, the foveolar lesion represents a photochemical injury to the retinal pigment epithelium and, hence, is similar to solar retinopathy, eclipse blindness, and arc-welder's retinopathy.