N-terminal DNA-binding domains contribute to differential DNA-binding specificities of NF-kappa B p50 and p65

We previously reported that either oxidation or alkylation of NF-kappa B in vitro abrogates DNA binding. We used this phenomenon to help elucidate structural determinants of NF-kappa B binding. We now demonstrate that Cys-62 of NF-kappa B p50 mediates the redox effect and lies within an N-terminal region required for DNA binding but not for dimerization. Several point mutations in this region confer a transdominant negative binding phenotype to p50. The region is highly conserved in all Rel family proteins, and we have determined that it is also critical for DNA binding of NF-kappa B p65. Replacement of the N-terminal region of p65 with the corresponding region from p50 changes its DNA-binding specificity towards that of p50. These data suggest that the N-terminal regions of p50 and p65 are critical for DNA binding and help determine the DNA-binding specificities of p50 and p65. We have defined within the N-terminal region a sequence motif, R(F/G)(R/K)YXCE, which is present in Rel family proteins and also in zinc finger proteins capable of binding to kappa B sites. The potential significance of this finding is discussed.     

The clinical platform for the 17beta-estradiol vaginal releasing ring

All women, regardless of race, culture, or socioeconomic background, experience urogenital atrophy as a result of hypoestrogenism from the menopause. As women go through the aging cycle, their vaginal and urethral epithelium become progressively deprived of estrogen and the tissue loses epithelial thickness, rugation, moisture, vasculature, and elasticity. The pH increases to above 5, infections in the urinary tract and vagina become more prevalent and cytologic study reflects loss of estrogen by a decrease in superficial cells and an increase in basal and parabasal cells. Replacement of estrogen to reverse these changes is the standard of care, with recent attention focused on the local delivery of estrogen by the vaginal route. The first vaginal ring delivery system of estrogen to the urogenital tract recently has been introduced, with the data confirming efficacy and safety of this delivery method for the treatment of urogenital atrophy. In addition, data on the 17beta-estradiol-releasing ring also support excellent patient acceptance of this local vaginal delivery system of estrogen therapy.     

The tissue distribution of porcine 17 beta-estradiol dehydrogenase and its induction by progesterone

Porcine 17 beta-estradiol dehydrogenase (EDH) was recently purified and cloned. It catalyzes the NAD(+)-dependent oxidation of estradiol to estrone 360-fold more efficiently than the back reaction with NADPH. The 32 kDa EDH is cut from an 80 kDa primary translation product with a multidomain structure unknown for other hydroxysteroid dehydrogenases. The highest EDH activities and strongest immunoreactions are found in liver (hepatocytes) and kidney (proximal tubuli) followed by uterus (luminal and glandular epithelium), lung (bronchial epithelium). Progesterone treatment of ovariectomized gilts stimulates oxidative EDH activity in uterus, anterior pituitary, skeletal muscle (diaphragm) and kidney. Constitutive levels of EDH activity were seen in the adrenals, the lung and the liver.     

2-Hydroxy-4-glutathion-S-yl-17beta-estradiol and 2-hydroxy-1-glutathion-S-yl-17beta-estradiol produce oxidative stress and renal toxicity in an animal model of 17beta-estradiol-mediated nephrocarcinogenicity

Measuring the vertical displacement of the center of mass (COM) of the body during walking may provide useful information about the energy required to walk. Four methods of varying complexity to estimate the vertical displacement of the COM were compared in 25 able-bodied, female subjects. The first method, the sacral marker method, utilized an external marker on the sacrum as representative of the COM of the body. The second method, the reconstructed pelvis method, which also utilized a marker over the sacrum, theoretically controlled for pelvic tilt motion. The third method, the segmental analysis method, involved measuring motion of the trunk and limb segments. The fourth method, the forceplate method, involved estimating the COM displacement from ground reaction force measurements. A two-tailed paired t-test within an ANOVA showed no statistically significant difference between the sacral marker and the reconstructed pelvis methods (p = 0.839). There was also no statistically significant difference between the sacral marker and the segmental analysis method (p = 0.119) or between the reconstructed pelvis and the segmental analysis method (p = 0.174). It follows that the first method, which is the most simple, can provide essentially the same estimate of the vertical displacement of the COM as the more complicated second and third measures. The forceplate method produced data with a lower range and a different distribution than the other three methods. There was a statistically significant difference between the forceplate method and the other methods (p < 0.01 for each of the three comparisons). The forceplate method provides information that is statistically significantly different from the results of the kinematic methods. The magnitude of the difference is large enough to be physiologically significant and further studies to define the sources of the differences and the relative validity of the two approaches are warranted.     

The fate of 17 beta-estradiol in the plasma of premenopausal and postmenopausal patients with cancer

The patterns of radioactive estrogen metabolities in the plasma of patients with a variety of malignancies were determined after the injection of physiological amounts of 17 beta-estradiol-6,7-3H or of estrone-6,7-3H. The metabolites were separated and isolated from the plasma by the following procedures: a) alumina chromatography, b) modified Brown procedure, and c) gas liquid chromatography. This study showed that the conjugated state of the estrogens varied with the subjects's age. There was a dramatic decrease in the relative quantity of the plasma free estrogens which are converted to sulfates as the age of the patient increased. This change was noted just prior to menopause, suggesting that there are alterations in the conjugation of plasma estrogens which are detectable before clinical menopause.     

Effects of 17 beta-estradiol on nitric oxide and ventricular myocardium metabolism

BACKGROUND: Arrhythmias are frequent pathology in patients with chronic hemodialysis. We evaluated whether a relatively new technique, signal averaging, could be useful in predicting the development of complex arrhythmias in these patients. METHODS: Thirty-three patients, 18 male and 15 female, subjected to thrice weekly chronic hemodialytic treatment with various dialysis techniques, were studied. Exclusion criteria were the presence of antiarrhythmic and inotropic treatment. The following examinations were carried out in all patients: a Holter dynamic electrocardiography for a duration of 24 hours, begun on the day of dialysis, high resolution ECG pre- and post-dialysis to find out if there were any ventricular late potential (VLP). Four hundred beats were examined in order to obtain a background noise of less than 0.7 microV and a better definition of the signal. The following parameters were considered significant for the presence of VLP: a) filtered QRS duration > 120 msec; b) the root mean square of the signal expressed in the terminal portion of QRS (RMS) < 25 microV) high frequency low amplitude signals duration (HFLA) > 40 msec. A positive value in two of these parameters was considered indicative of the presence of VLP. In addition various pre and post-dialysis indices of dialytic efficiency and a mono and two-dimensional echocardiogram with pulsed and color Doppler were carried out. Of the 33 patients studied, ten were excluded because they presented too high a background noise at the high resolution ECG. Of the remaining 23 patients, 13 (56%) presented VLP and nine of these (69%) presented complex arrhythmias. Of the ten patients without VLP, 5 (50%) presented complex arrhythmias. The incidence of arrhythmias was highest during the last two hours of dialysis and in the two hours following it. The patients were then divided into two groups (A and B) according to the ejection fraction (EF) found at the echocardiogram. Group A was composed of 17 patients of whom 8 (47%) presented complex arrhythmias; group B (EF < 45%) was composed of the remaining six patients, who all presented complex arrhythmias. In group A nine patients (53%) out of 17 had LVP, in group B four out of six (66%) had it. All the patients except one presented an increase in the thickness of the ventricular wall and alterations of Doppler transmitral filling rate. Left ventricular hypertrophy was diagnosed in 22 out of the 23 patients. Four patients also had chronic ischaemic heart disease; of these three had LVP. There was no correlation between the presence of LVP and the hemodialytic indices and between the latter and complex arrhythmias. CONCLUSIONS: Our study showed that arrhythmias are more frequent in patients with LVP before dialysis than in those without. The difference was statistically significant (p < 0.006); the incidence of arrhythmias was higher in patients with FE < 45% (p < 0.001). The majority of patients (95%) had left ventricular hypertrophy; only four (17%) had ischaemic heart disease too. It is highly probable that the presence of LVP in our patients can be attributed to hypertension and subsequent left ventricular hypertrophy. As patients with LVP at the end of dialysis had a greater incidence of arrhythmias than those without LVP, we suggest that this method could be useful as a first screening in dialysed patients.     

Comparison between urinary pyridinium cross-links and hydroxylysine glycosides in monitoring the effects of ovariectomy and 17 beta-estradiol replacement in aged rats

This study was undertaken to assess the sensitivity of hydroxylysylpyridinoline (HP), lysylpyridinoline (LP), galactosylhydroxylysine (GHyl) and glucosylgalactosylhydroxylysine (GGHyl) to monitor bone response to estrogen deficiency and replacement by comparing their excretory patterns in ovariectomized aged (11-14 months old) rats. The ovariectomized (OVX) rats were randomized into two groups: (1) OVX plus vehicle; (2) OVX plus 17 beta-estradiol (17-beta E, 10 micrograms/kg, s.c., 4 days/week). Treatment with 17-beta E started immediately after OVX and continued for 60 days. The collagen catabolites were measured in urine for 1 month before OVX and thereafter for 60 days. In temporal coincidence with urine collection, bone area and bone mineral density (BMD) of lumbar vertebrae, femoral diaphysis and distal metaphysis were measured by dual-energy X-ray absorptiometry. In the untreated rats, BMD of the femoral metaphysis and lumbar vertebrae decreased significantly and the urinary excretion of LP, HP, GHyl and GGHyl increased with different patterns. In the treated rats, 17-beta E replacement prevented the increment in LP excretion, partially prevented the increase in HP excretion, but had no effect on the excretion of GHyl and GGHyl. In conclusion pyridinolines and glycosides have different sensitivities to the bone response to OVX. Glycoside excretion after OVX also reflects metabolic processes not strictly related to bone loss and, in contrast with LP, is not sensitive to estrogen replacement.     

DNA-binding properties of the yeast transcriptional activator, Gcr1p

In Saccharomyces cerevisiae the GCRI gene product is required for high-level expression of genes encoding glycolytic enzymes. In this communication, we extend our analysis of the DNA binding properties of Gcr1p. The DNA-binding domain of Gcr1p binds DNA with high affinity. The apparent dissociation constant of the Gcr1p DNA-binding domain for one of its specific binding sites (TTTCAGCTTCCTCTAT) is 2.9 x 10(-10) M. However, competition experiments showed that Gcr1p binds this site in vitro with a low degree of specificity. We measured a 33-fold difference between the ability of specific competitor and DNA of random sequence to inhibit the formation of nucleoprotein complexes between Gcr1p and a radiolabeled DNA probe containing its binding site. DNA band-shift experiments, utilizing probes of constant length in which the positions of Gcr1p-binding sites are varied relative to the ends, indicated that Gcr1p-DNA nucleoprotein complexes contain bent DNA. The implications of these findings in terms of the combinatorial interactions that occur at the upstream activating sequence elements of genes encoding glycolytic enzymes are discussed.     

Role of gender and vascular endothelium in rat aorta response to 17 beta-estradiol

Estrogen supplementation in postmenopausal women offers significant cardiovascular protection. The mechanism for this benefit is unclear but may be due to an interaction of estrogen with the blood vessel wall (vascular smooth muscle and endothelium). We examined the response of weight-matched female and male endothelium-intact and -denuded aortae to 17 beta-estradiol, its interaction with noradrenaline, and the effect of N-nitro-L-arginine. Estradiol produced relaxation responses that were significantly greater in female endothelium-intact preparations. This response was sensitive to N-nitro-L-arginine, while the response to 17 beta-estradiol in male endothelum-intact and both female and male endothelum-denuded preparations was resistant. Estradiol also inhibited contractions to noradrenaline, which was more pronounced in the female endothelium-intact aortic rings. These data imply that estradiol interacts preferentially with the female vascular endothelium, but there exists an endothelium-independent process that can also be activated in the male aorta. Further studies are warranted to elucidate these differential mechanisms.     

The effect of 17 beta-estradiol and endothelin 1 on prostacyclin and thromboxane production in human endothelial cell cultures

The authors present an account on a neonate with dextro-lateral renal venous thrombosis. They focus attention on the diagnostic and therapeutic procedure and compare it with available data from the literature. Contrary to data in the literature, they did not observe in the acute stage of renal venous thrombosis signs of disseminated intravascular coagulation in peripheral blood. It did not prove possible to elucidate the action of any of the factors leading to the development of renal venous thrombosis. After evidence of permanent functional loss of the right kidney nephrectomy was performed. Histopathological examination provided evidence of obliterating thrombosis of the renal veins with partial recanalization and calcifications. The authors emphasize the necessity of early diagnosis of renal venous thrombosis and adequate treatment based on the revealed findings.     

In vitro growth of skin fibroblasts of patients with atypical ductal hyperplasia of the breast: effects of 17 beta-estradiol

In this work we investigated the growth of skin fibroblasts, in vitro cultured, drawn from women suffering Atypical Ductal Hyperplasia (I.D.A.) and from healthy women (controls). Whether in basic conditions or after administration of 17, beta-estradiol, in single of repeated dose, cellular growth was valued. The results obtained show that skin fibroblasts drawn from women suffering I.D.A. treated with 100 microliters/ml of estradiol (effective dose), have an increase of the growth. Moreover the increase of the growth seems to be bequest to "effective dose" but not to the number of administrations.     

Effect of 17beta-estradiol on somatostatin receptor expression and inhibitory effects on growth hormone and prolactin release in rat pituitary cell cultures

Predictions of the minimal size an organism must have to swim along stimulus gradients were used to compare the relative advantages of sensory systems employing spatial (simultaneous) and temporal (sequential) gradient detection mechanisms for small free-swimming bacteria, leading to the following conclusions: 1) there are environmental conditions where spatial detection mechanisms can function for smaller organisms than can temporal mechanisms, 2) temporal mechanisms are superior (have a smaller size limit) for the difficult conditions of low concentration and shallow gradients, but 3) observed bacterial chemotaxis occurs mostly under conditions where spatial mechanisms have a smaller size limit, and 4) relevant conditions in the natural environment favor temporal mechanisms in some cases and spatial mechanisms in others. Thus, sensory ecology considerations do not preclude free-swimming bacteria from employing spatial detection mechanisms, as has been thought, and microbiologists should be on the lookout for them. If spatial mechanisms do not occur, the explanation should be sought elsewhere.