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Relationship between the concentrations of estriol sulfate and estrone sulfate in human breast cyst fluid.

Estriol-3-sulfate (E3S) is present in human breast cyst fluid (BCF) in median levels of 8.7-10.4 nmol/L, yet is barely detectable in the serum (less than 0.034 nmol/L). The source of this huge concentration of E3S is unknown. It may accumulate from blood by active transport or be synthesized and concentrated within the cyst. Since estrone sulfate (E1S) and its possible precursor, dehydroepiandrosterone sulfate (DHEAS) are elevated in BCF, E3S may originate via 16 alpha-hydroxylation of E1S. The present study examined the correlations between the levels of DHEAS and E1S with those of E3S in BCF. The sodium and potassium ions were also quantified and related to the steroid concentrations. By linear regression analysis of log-normalized data there was a highly significant correlation between the concentrations of E1S and E3S (n = 355, r = 0.690, P less than 0.001) and between DHEAS and E3S (n = 361, r = 0.577, P less than 0.001). The BCF were classified according to their K/Na ion ratios: type 1, greater than 1.0, type II, less than 0.25, and type III, 0.25-1.0. By Student's t test, the concentrations of E3S differed between each BCF Type (P less than 0.002). This was also true for E1S and DHEAS. Type 1 cysts were associated with the highest estrogen sulfate levels and type II with the lowest levels. The possible physiological importance of this observation resides in reports that the BCF type expressing the highest steroid concentrations has been related to an aporcine-like epithelial lining of the cyst wall and a somewhat higher risk for developing breast cancer. The results suggest that E3S in BCF may originate from E1S, but alternate mechanisms are not precluded.

Aryl Hydrocarbon Hydroxylases

Relationships between androgen and estrogen sulfates in breast cyst fluid.

In 28 breast cyst fluids obtained from 20 patients (age 29-65 years) sodium, potassium and the sulfates (S) of estrone (E1), estradiol (E2), dehydroepiandrosterone (DHEA) and androsterone (A) were determined. The radioimmunoassays (RIA) used were validated for this particular biological fluid. According to electrolyte ratio (Na+/K+) the cyst fluids were subdivided into two groups: the first with low (less than 3) (n = 16) and the other with high (greater than 3) (n = 12) values. Markedly higher steroid sulfate levels were observed in the first group, the mean levels being: 147.7 nmol/l, 54.6 nmol/l, 108.1 mumol/l and 158.0 mumol/l for E1S, E2S, DHEAS and AS respectively. The mean levels in the second group were: 13.6 nmol/l, 6.7 nmol/l, 68.8 mumol/l and 33.6 mumol/l for E1S, E2S, DHEAS and AS, respectively. In the first group only E1S and E2S levels were significantly correlated (r = 0.51; P less than 0.05). Conversely, the steroid sulfate levels were significantly correlated with each other in the group with high electrolyte ratio. These data have confirmed preceding results and have clearly shown that breast cyst fluids with low electrolyte ratio contain more E2S than the other group. This finding might be correlated with the fact that patients with these breast cysts lined by with apocrine epithelium may be at a greater risk of breast cancer than those with the other type.

Adult

Estrone sulfate and dehydroepiandrosterone sulfate concentrations in normal subjects and men with cirrhosis.

Circulation levels of estrone sulfate (E1S) and dehydroepiandrosterone sulfate (DHAS) have been measured in plasma using a radioimmunoassay for estrone and dehydroepiandrosterone following extraction and hydrolysis of the sulfate. The mean +/- SE concentrations of E1S and DHAS in normal men were 458 +/- 25 pg/ml and 1.45 +/- 0.19 micrograms/ml, respectively. In normal women the values for days 5-7 of the cycle were 880 +/- 117 pg/ml and 1.25 +/- 0.12 micrograms/ml which were not different than the values for days 20-22 of 1195 +/- 176 pg/ml and 1.58 +/- 0.29 micrograms/ml. The mean values in post-menopausal women were 250 +/- 33 pg/ml and 0.47 +/- 0.07 micrograms/ml, both lower than the values in young women. In a group of cirrhotic men the mean values were 325 +/- 55 pg/ml and 0.38 +/- 0.12 micrograms/ml, both significantly lower than the normal values. This suggests a defect in sulfurylation in men with hepatic cirrhosis.

Adult

Structural difference at the active site of dibucaine resistant variant of human plasma cholinesterase.

Human plasma cholinesterase from five different genotypes -- E1U E1U, E1U E1A, E1A E1A, E1U E1S, E1A E1S, and E1U E1U C5+ -- was purified 8,000 fold from serum by a two-step procedure involving chromatography on DEAE-cellulose and preparative disc electrophoresis. The esterases were labeled with diisopropyl-1, 3-C14-fluorophosphate (DFP) aminoethylated, and digested by trypsin. The trytic digests were subjected to high voltage electrophoresis, and the radioactive peptides were detected by radioautography. Comparison of the peptides revealed different electrophoretic mobilities of the usual and atypical (dibucaine resistant) plasma cholinesterase peptides. The results are consistent with a structural abnormality of the active center in the variant enzyme. No difference was observed an the esteratic site of the enzyme with C5 component.

Binding Sites

Population genetic studies of the Aka pygmies (Central Africa): a survey of red cell and serum enzymes.

Blood samples collected in a single Pygmy tribe, the Aka, living in Bokoka district (Central African Empire) were investigated with respect to the phenotype and gene frequencies of the following 12 enzyme systems: acid phosphatase, adenosine deaminase, adenylate kinase, carbonic anhydrase, esterase D, glucose-6-phosphate dehydrogenase, malate dehydrogenase, phosphoglucomutase 1, phosphoglucomutase 2, phosphogluconate dehydrogenase, superoxide dismutase and serum cholinesterase variants (locus E1 and E2). The data obtained in the study of genetic polymorphisms of this isolated and inbred population show a specific pattern with the following characteristics: the very low frequency of PGDB and pa alleles; the existence of two rare PGM variants at the PGM2 locus, typical PGM26Pyg (4.2%) and PGM29 (0.2%); the high frequency of the pr allele (10.8%) and CAII2 (8.22%) and ESD2 genes (18.4%). Furthermore, at the G6PD locus four distinct alleles have been found: the negroid GdA- (4%) and GdA+ (16%), the common GdB+ (79.2%)--, and the rare Gd+Ibadan Austin (0.7%). Cholinesterase typings disclosed the presence of the uncommon E1f and E1s genes distributed within a single breeding unit. The results are compared with other data previously reported on South African Khoisan and some Negroid populations; the particular genetic background of Pygmies is discussed.

Black People

Characterization of the antibody response to three different versions of the HTLV-I envelope protein expressed by recombinant vaccinia viruses: induction of neutralizing antibody.

Recombinant vaccinia viruses (RVV) designated RVV E1, RVV E2, and RVV E3, were constructed to express three different versions of the human T cell leukemia virus type I (HTLV-I) envelope proteins to determine which configuration elicits an optimal antibody response. RVV E1 expressed the native HTLV-I envelope proteins gp46 (surface protein) and gp21 (transmembrane protein), while RVV E2 expressed the envelope precursor with the proteolytic cleavage site deleted. The RVV E3 construct expressed only the external surface glycoprotein, gp46. Radioimmunoprecipitation and FACS analysis confirmed that the appropriate envelope proteins were expressed by RVV E1-, E2-, and E3-infected cells. Immunization studies were carried out using Balb/c, A/J, and C57BL/6 strains of mice. Balb/c mice responded poorly to immunization with all of the three RVV constructs. C57BL/6 mice produced neutralizing antibodies in response to immunization with all three constructs, whereas A/J mice developed neutralizing antibodies only when immunized with the RVV E1s construct. The results indicate that the humoral immune responses depend on the form of HTLV-I envelope proteins expressed by each RVV.

Animals

[Rheological studies of interphase adsorption layers of lysozyme at phase separation liquid boundaries].

Rheological studies of thin layers of biopolymers provide a principally new approach to the studies of the structure and functions of biomembranes. Rheological properties of interphase adsorption layers of lysozyme at different concentrations, temperatures and at the border with various carbohydrates. The values of moduli of fast elastic deformation E1s, slow elastic deformation E2s, equilibrium module of elasticity Es, viscosity of elastic aftereffect, plastic viscosity eta 0s and eta s for the interphase layers of lysozyme at liquid borders show that the interphase adsorption layers were solidlike, and the moduli of dimeric structure evaluated as volume ones correspond to the characteristics of normal elastomeres.

Adsorption

Beyond the CO-FT regulatory module: E1 and PHYA emerge as players in photoperiodic regulation of flowering in legumes.

The legume family (Fabaceae) is the third largest in plants and includes several crop species that are able to fix nitrogen, promote soil health, and contribute to food security worldwide. Recent progress in legume genetics and genomics allowed the identification of photoperiod-dependent flowering loci, which were incorporated into specific signalling networks. Functional characterization of these regulators revealed new roles for known photoreceptors such as phytochrome A, and it also identified legume-specific B3 domain transcriptional factors (E1 and E1-like proteins). This suggests some diversification from the traditional CONSTANS-FLOWERING LOCUS T module present in other angiosperms. Although most of the findings discussed herein pertain to species from the two main legume clades, the Galegoids (e.g. alfalfa, clover, and pea) and the Phaseoloids (e.g. common bean, soybean, cowpea, and pigeon pea), research on flowering regulation in the basal Genistoid clade (e.g. lupins) will also be addressed. We propose that functional diversification of photoperiod-dependent flowering strategies in the different legume species could have contributed to their environmental adaptation and allowed their geographical expansion and success worldwide.

Photoperiod