Evidence for age-related change in plasma 19-hydroxyandrostenedione

The steroid, 19-hydroxyandrost-4-ene-3, 17-dione (19-hydroxyandrostene-dione, 19-OH-A-dione) has been known to enhance the mineralocorticoid action of aldosterone. To investigate the age-related change in the plasma 19-OH-A-dione concentration, plasma 19-OH-A-dione, androst-4-ene-3, 17-dione (A-dione), aldosterone and cortisol of 38 non-hypertensive healthy subjects (18 young men and 20 aged men) measured by specific radioimmunoassays. The basal plasma 19-OH-A-dione and A-dione concentration in aged men was significantly lower than in young men (P less than 0.01). Moreover, there was found to be a positive correlation between plasma 19-OH-A-dione and A-dione (P less than 0.01). On the other hand, plasma aldosterone and cortisol in aged men showed a tendency to decrease, but no statistical significance compared to young men was observed. This study demonstrated that there was an apparent age-related decrease not only in plasma A-dione, but also in plasma 19-OH-A-dione, an amplifier or aldosterone action.     

Proteolytic processing of Blattella germanica vitellin during early embryo development

In the eggs of the cockroach Blattella germanica, vitellin (Vt) utilization is initiated 4 days postovulation by the proteolytic processing of its three subunits. These reactions yield a specific set of peptides that are consumed by the developing embryo. A yolk proteinase activity, believed central to this processing event, has been investigated. First expressed at day 3 postovulation, just prior to Vt's processing, its specific activity with synthetic substrates increased four-fold to 18-fold through day 6. In addition, a mixing experiment showed that these proteinases(s) can also process Vt's large subunits in vitro. A relationship between Vt processing and proteinase specific activity was also noted with two B. germanica translocation heterozygotes, which displayed differences in the extent of Vt processing. One group of eggs (group A) failed to process any Vt subunit. A second group (B) processed the M_r 102,000 subunit but not the M_r 95,000. A third group (C) processed their Vt normally. Proteinase specific activities in the yolk of translocant's eggs at day 6 mirrored the extent of processing, being highest in group C eggs and effectively absent from the yolk of group A eggs. Eggs defective in Vt processing also contained arrested embryos. It is concluded that the yolk proteinase activity described here participates in Vt processing at day 4 postovulation. Microscopic examination of yolk obtained from eggs of wild type females showed that, as processing began in vivo (day 4), the yolk granules also underwent an abrupt decrease in size from diameters of 15–30 μm to 3–10 μm. Yolk granules of those translocant's eggs that were defective in Vt processing did not undergo this size decrease, suggesting that granule reorganization and Vt proteolysis may be linked functionally.     

A case of glucocorticoid-suppressible hyperaldosteronism with aldosterone producing adenoma

A 34-yr-old woman with hypertension (142/102 mmHg), hypokalemia, high plasma and urinary aldosterone and low plasma renin activity was studied. A left adrenal tumor and enlarged right adrenal gland were demonstrated by adrenal venography. During administration of dexamethasone (2 mg daily, for 3 weeks), urinary aldosterone excretion decreased abruptly from 22.5 to 9-11 micrograms/day, serum potassium increased and blood pressure fell to 120-130/80-90 mmHg. After left adrenalectomy, all manifestations improved with no medication. The resected adrenal gland revealed clear cell adenoma and micronodular adrenocortical hyperplasia. The patient was considered to be a rare case of glucocorticoid-suppressible hyperaldosteronism with an aldosterone-producing adenoma.     

Technical note on the demonstration of rheumatoid factor by immunofluorescence

The authors present a new technic to point out the rheumatoid factor by immunofluorescence and compare this technic and the others to classical technics of agglutination. This technic allows to avoid the absorption of rheumatoid factor in the serological reactions using the immunofluorescence.     

The effect of calcium supplements on plasma alkaline phosphatase and urinary hydroxyproline in postmenopausal women

Although calcium supplements are widely used in the treatment of osteoporosis, their beneficial effect is not conclusively established. We now report some effects of a calcium supplement (1 g/day) given for 6 to 12 weeks to 15 postmenopausal osteoporotic women. The mean fasting urinary hydroxyproline/creatinine ratio decreased from 0.021 +/- 0.002 to 0.015 +/- 0.001 (P less than 0.0025), indicating a significant reduction in bone resorption. The mean plasma alkaline phosphatase fell from 123 +/- 5 U/l to 104 +/- 3.1 U/l (P less than 0.01), probably representing some secondary reduction in bone formation following the inhibition of bone resorption. These results support the concept that calcium supplementation is useful in the treatment of postmenopausal osteoporosis.     

Abscisic acid deficiency prevents development of freezing tolerance in Arabidopsis thaliana (L.) Heynh.

Summary Abscisic acid (ABA) has been implicated as a regulatory factor in plant cold acclimation. In the present work, the cold-acclimation properties of an ABA-deficient mutant (aba) of Arabidopsis thaliana (L.) Heynh. were analyzed. The mutant had apparently lost its capability to cold acclimate: the freezing tolerance of the mutant was not increased by low temperature treatment but stayed at the level of the nonacclimated wild type. The mutational defect could be complemented by the addition of exogenous ABA to the growth medium, restoring freezing tolerance close to the wild-type level. This suggests that ABA might have a central regulatory function in the development of freezing tolerance in plants. Cold acclimation has been previously correlated to the induction of a specific set of proteins that have been suggested to have a role in freezing tolerance. However, these proteins were also induced in the aba mutant by low temperature treatment.     

Porcine brain natriuretic peptide receptor in bovine adrenal cortex

The action of porcine brain natriuretic peptide (pBNP) on the steroidogenesis was investigated in cultured bovine adrenocortical cells. Porcine BNP induced a significant dose-dependent inhibition of both ACTH- and A II-stimulated aldosterone secretion. 10(-8) M and 10(-7) M pBNP also significantly inhibited ACTH-stimulated cortisol and dehydroepiandrosterone (DHEA) secretions. Binding studies of [125I]-pBNP to bovine adrenocortical membrane fractions showed that adrenal cortex had high-affinity and low-capacity pBNP binding sites, with a dissociation constant (Kd) of 1.70 x 10(-10) M and a maximal binding capacity (Bmax) of 19.9 fmol/mg protein. Finally, the 135 Kd radioactive band was specially visualized in the affinity labeling of bovine adrenal cortex with disuccinimidyl suberate (DSS). These results suggest that pBNP may have receptor-mediated suppressive actions on bovine adrenal steroidogenesis, similar to that in atrial natriuretic peptide (ANP).     

Molecular cloning, sequence analysis and expression of a cDNA encoding human type-1 angiotensin II receptor.

We isolated a cDNA encoding type-1 angiotensin II receptor from a human liver cDNA library. The cDNA had an open reading frame encoding a protein of 359 amino acid residues with a relative Mr of 41,060. The deduced amino acid sequence of the human angiotensin II (Ang II) receptor was 95.3% and 94.2% identical to those of bovine and rat type-1 Ang II receptors, respectively, and had a significant similarity with the G protein-coupled receptor. The rank order of the binding to the receptor expressed in COS-7 cells was Ang II greater than Ang III greater than Ang I. The expression of the Ang II receptor mRNA was detected in human liver, lung, adrenal and adrenocortical adenomas but not in adrenomedullary tumor, pheochromocytoma, by Northern blot analysis.     

Study of quercetin and fisetin synergistic effect on breast cancer and potentially involved signaling pathways

Naturally-derived drugs have drawn much attention in recent decades. Efficiency, lower toxicity, and economic reasons are some of their advantages that justify this broad range of administration for different diseases, including cancer. If we can find a specific combination that boosts the effects of their single therapy, leading to synergism effect, increased efficiency, and decreased toxicity, they can act even better. Quercetin and fisetin, two well-known flavonoids, have been used to fight against various cancers. In this study, we investigated their possible synergism quercetin and fisetin on MCF7, MDA-MB-231, BT549, T47D, and 4T1 breast cancer cell lines. Then the optimum combined dose was used to study their impacts on wound healing abilities and clonogenic properties. The real-time qPCR was used to study the expression of their validated downstream effectors in predicted pathways. A significant synergism effect (p < .01, combination index: <1) was observed for all cell lines. Combination therapy was significantly more effective in colony formation (p < .0001) and wound healing assays (p < .001) compared to single therapies. The expression level of potential effectors was also showed a greater change. In vivo study confirmed the in vitro results and showed how significantly (p < .001) their synergism promotes their singular function in inhibiting cancer progression. The breast cancer mouse models receiving combined therapy lived longer with higher average body weight and smaller tumor sizes. These results exhibit that quercetin and fisetin inhibit cancer cell proliferation, migration and colony formation synergistically, and matrix metalloproteinase signaling and apoptotic pathways are relatively responsible for inhibitory activities.