Total AR Research Articles

Content and relative composition of some phytochemicals in diploid, tetraploid and hexaploid Triticum species with potential nutraceutical properties

Seven cultivated Triticum species or subspecies (Triticum monococcum, Triticum turgidum ssp dicoccum, T. turgidum ssp. durum, T. turgidum ssp turanicum, Triticum timopheevii, Triticum aestivum and Triticum zhukovskyi) were compared for their contents of bioactive compounds, mainly 5-n-alkylresorcinols (ARs). Multivariate analysis of variance and principal component analysis were used to evaluate the differences in the phytochemical profiles and to establish the relationships among variables. Significant differences were observed for both total phenol (TP) and AR content. The highest AR level (377 μg/g) was observed in Triticum dicoccum, which also exhibited the highest variability for these compounds (298–436 μg/g). By contrast, the lowest AR content (286 μg/g) was found in Triticum durum. C21:0 was the main homologue chain in all the samples, its value ranging between 54.5% in T. durum and 41.2% in T. aestivum. The T. dicoccum and T. monococcum wheats had relatively low amounts of TP, whereas Triticum turanicum (215 mg/kg), T. timopheevii (250 mg/kg) and T. zhukovskyi (286 mg/kg) had approximately 3-fold higher TP levels. These results suggest that there are opportunities for breeding wheat varieties with superior health benefits and for promoting the use of ancient Triticum crops as novel sources of healthy food.

Testicular Development in Mice Lacking Receptors for Follicle Stimulating Hormone and Androgen

Post-natal testicular development is dependent on gonadotrophin and androgen stimulation. Follicle stimulating hormone (FSH) acts through receptors (FSHR) on the Sertoli cell to stimulate spermatogenesis while androgens promote testis growth through receptors (AR) on the Sertoli cells, Leydig cells and peritubular myoid cells. In this study we have examined the effects on testis development of ablating FSHRs (FSHRKO mice) and/or ARs ubiquitously (ARKO mice) or specifically on the Sertoli cells (SCARKO mice). Cell numbers were measured using stereological methods. In ARKO mice Sertoli cell numbers were reduced at all ages from birth until adulthood. FSHR ablation also caused small reductions in Sertoli cell numbers up to day 20 with more marked effects seen in the adult. Germ cell numbers were unaffected by FSHR and/or AR ablation at birth. By day 20 ubiquitous AR or FSHR ablation caused a marked reduction in germ cell numbers with a synergistic effect of losing both receptors (germ cell numbers in FSHRKO.ARKO mice were 3% of control). Germ cell numbers in SCARKO mice were less affected. By adulthood, in contrast, clear synergistic control of germ cell numbers had become established between the actions of FSH and androgen through the Sertoli cells. Leydig cell numbers were normal on day 1 and day 5 in all groups. By day 20 and in adult animals total AR or FSHR ablation significantly reduced Leydig cell numbers but Sertoli cell specific AR ablation had no effect. Results show that, prior to puberty, development of most testicular parameters is more dependent on FSH action than androgen action mediated through the Sertoli cells although androgen action through other cells types is crucial. Post-pubertally, germ cell numbers and spermatogenesis are dependent on FSH and androgen action through the Sertoli cells.

The relationship of testosterone and AR CAG repeat genotype with knee extensor muscle function of young and older men

The inter-relationship between muscle strength and serum testosterone is not fully understood, and may be confounded or influenced by age. The polymorphism of androgen receptor gene CAG number (AR CAGn) could also influence these variables. The study examined the relationship between total testosterone (TT), free testosterone (FT) and AR CAGn with the muscle strength of young (YM, 18–30yrs, n=82) and older (OM, 60–70yrs, n=101) Caucasian men. Knee extensor strength was measured isometrically and isokinetically, and thigh and whole-body lean mass of the OM was determined by DXA. TT and serum hormone binding globulin (SHBG) were assayed by ELISA and used to calculate FT. AR CAGn was determined using polymerase chain reaction and microchip electrophoresis. OM were weaker than YM (−20 to −29%, all P<0.001), and serum androgens were lower (TT, −13%; FT, −13%; both P<0.001). TT was unrelated to any strength measurement in YM or OM. In the OM only, FT had a weak positive association with all three strength measures (r2=4.1–9.3%, P<0.036) and both whole body and thigh lean mass (r2=6.1–8.6%; P<0.013). Muscle strength was unrelated to AR CAGn for either the YM or OM, or when data were collapsed across both age groups (age normalised strength). Lean mass in the older cohort was also independent of AR CAGn. In conclusion, FT, but not TT or AR CAGn, was positively associated with muscle strength, but only as values declined with age.

Ligand-independent activation of the androgen receptor by insulin-like growth factor-I and the role of the MAPK pathway in skeletal muscle cells.

In this study, the roles of the p38 MAPK, ERK1/2 and JNK signaling pathway in IGF-I-induced AR induction and activation were examined. C2C12 cells were treated with IGF-I in the absence or presence of various inhibitors of p38 MAPK (SB203580), ERK1/2 (PD98059), and JNK (SP600125). Inhibition of the MAPK pathway with SB203580, PD98059, or SP600125 significantly decreased IGF-I-induced AR phosphorylation and total AR protein expression. IGF-I-induced nuclear fraction of total AR and phosphorylated AR were significantly inhibited by SB203580, PD98059, or SP600125. Furthermore, IGF-I-induced AR mRNA and skeletal alpha-actin mRNA were blocked by those inhibitors in dose-dependent manner. Confocal images showed that IGF-I-induced AR nuclear translocation from cytosol was significantly blocked by SB203580, PD98059, or SP600125, suggesting that the MAPK pathway regulates IGF-I-induced AR nuclear localization in skeletal muscle cells. The present results suggest that the MAPK pathways are required for the ligand-independent activation of AR by IGF-I in C2C12 skeletal muscle cells.

Insulin-like growth factor-I induces androgen receptor activation in differentiating C2C12 skeletal muscle cells.

The modulating effect of IGF-I on the regulation of AR gene expression and activation in skeletal muscle cells remains poorly understood. In this study, the effects of IGF-I treatment on AR induction and activation in the absence of AR ligands were examined. Differentiating C2C12 cells were treated with different concentrations (0-250 ng/ml) of IGF-I or for various periods of time (0-60 min) of 250 ng/ml IGF-I. Treatment of C2C12 cells with IGF-I resulted in a dose- and time-dependent increase in total AR and phosphorylated AR (Ser 213). IGF-I treatment also led to significantly increased AR mRNA expression when compared with the control. The levels of skeletal alpha-actin and myogenin mRNA, known target genes of AR, were also significantly upregulated after 5 or 10 min of treatment with IGF-I. Confocal images revealed that IGF-I stimulated nuclear localization of AR in the absence of ligands. In addition, an electrophoretic mobility shift assay indicated that IGF-I stimulated the AR DNA binding activity in a time-dependent manner. The present results suggest that IGF-I stimulates the expression and activation of AR by ligand-independent mechanism in differentiating C2C12 mouse skeletal muscle cells.

Direct Quantitative Determination of Total Arsenic in Natural Hotwaters by Anodic Stripping Voltammetry at the Rotating Lateral Gold Electrode

A simple, rapid, selective and sensitive differential pulse anodic stripping voltammetric (DPASV) technique for the direct quantitative determination of inorganic total arsenic in natural hotwater was developed. The electrochemical de- termination of total arsenic has been carried out at the novel rotating lateral gold electrode in hydrochloric acid solution (37 % w/w). The analysis was performed with a special gold electrode whose active surface was located on the side. Re- productivity of measurement was achieved by the conditioning of the gold electrode. This was done every day before the measurements as well as when the background current varied strongly from measurement to measurement. The determina- tion limit of 0.5 � g L -1 was achieved with 10 mL sample solution. The total arsenic concentration was made by appropri- ate selection of the deposition potential. During the deposition step, the total arsenic content was reduced at -1200 mV by nascent hydogen to As o . During the subsequent voltammetric determination, the preconcentration As o was again oxidized to determine the level. The method was applied successfully to the direct quantitative determination of total inorganic ar- senic in hotwater. In order to show the accuracy of the results developed from voltammetric technique, the values obtained were compared with those obtained from inductively coupled plasma mass spectrometry (ICP-MS).

The Self-Inversion of the Sign of Circular Polarization in “Halo” Microwave Sources

The large active region AR NOAA 5200 from October 1988 is used to investigate the concept of the “halo,” a magnetosphere-like structure above the active region. This structure is studied by using radio spectral polarization observations with high spatial resolution obtained mainly with the radio telescope RATAN-600. In the case of AR 5200 the halo emission accounted for >50% of the total AR emission. The results of the analysis of the observational data and of the model calculations allow us to reach the following conclusions: (1) The halo is a large, nonstructured, source of emission with a size of the total AR, with the emission centered at the dividing (neutral) line of polarities of the bipolar sunspot group. (2) The emission spectrum allows us to distinguish two components: a thermal part and a nonthermal part. The presence of two components implies that there are two populations of particles with different energy levels in the emission region. The phenomenon of inversion of the polarized halo radio emission could be explained by the influence of propagation conditions inside the source. The term “self-inversion” is introduced. The maximum in the halo density flux spectrum at wavelengths of 5 –10 cm may be explained by scattering resulting from the strong suppression of the emissivity of nonthermal electrons at these and longer wavelengths.

Active region AR484 tracking with Solar Feature Catalogue

This paper presents a morphological analysis of the active region NOAA AR 484 as well as its intensity and magnetic field variations associated with flare occurrences. The active region is tracked during a one solar rotation with the automated technique used in Solar Feature Catalogue (SFC). The location and intensity parameters of region AR484 were extracted from 1 minute cadence Hα solar images from the Big Bear observatory (BBSO), SOHO/EIT images in Fe XII, 195 Å and the SOHO/MDI magnetograms. During the whole period of tracking from October, 19 until November, 11, 2003 the AR484 produced many flares of different significance including a few X-class flares. We investigate the total AR intensity variations in each band leading to a flare production and compare these with the magnetic field changes before and during a flare for five flares of different significance. Based on this comparison the key parameters defining the region activity in a flare production are found that include the resulting, or excess, flux and the ratio between areas covered by negative and positive pixels. These parameters can be used for a preliminary pre-flare classification of active regions in addition to other classifiers associated with a magnetic field.

Long-term exposure of tumor necrosis factor alpha causes hypersensitivity to androgen and anti-androgen withdrawal phenomenon in LNCaP prostate cancer cells.

One of the mechanisms through which prostate cancers relapse during anti-androgen therapy may involve adaptation to low concentrations of androgen induced by anti-androgen therapies. Recent studies from our laboratory have reported that tumor necrosis factor-alpha (TNFalpha) is secreted from prostate cancer epithelial cells and LNCaP cells. We hypothesized that TNFalpha changes androgen-sensitivity in LNCaP cells. We cultured LNCaP cells for more than 3 months in the presence of 50 ng/ml TNFalpha and established TNFalpha-resistant LNCaP cells (LN-TR2). Sensitivity to androgen was examined by the cell proliferation assay. We also transfected LNCaP and LN-TR2 cells with a luciferase reporter plasmid driven by prostate-specific antigen (PSA) promoter and compared PSA promoter activity. Nuclear localization of AR protein that binds to target genes was also examined by Western blotting. LN-TR2 cells had increased sensitivity to dihydrotestosterone (DHT) (i.e., proliferation and PSA promoter activation) than LNCaP cells. Total AR mRNA and AR protein levels were decreased in LN-TR2 cells. However, LN-TR2 cells demonstrated increased levels of nuclear AR compared to LNCaP cells. At 1 nM DHT, the anti-androgen bicalutamide stimulated LN-TR2 and inhibited LNCaP proliferation. Long-term exposure of TNFalpha causes hypersensitivity to DHT in LNCaP and this was associated with increased nuclear AR protein. Furthermore, hypersensitivity to androgen caused anti-androgen withdrawal phenomenon in the presence of DHT although bicalutamide itself did not stimulate LNCaP proliferation without androgen. This result may be one possible mechanism for the anti-androgen withdrawal phenomenon.

Stepwise postglacial migration of benthic foraminifera into the abyssal northeastern Norwegian Sea

Accumulation rates of individual species (SpecAR) and relative abundances (percentages) of benthic foraminifera of an AMS 14C-dated high resolution sediment core from the Norwegian Seas (water depth: 2707 m) provide a record of the faunal fluctuations from the last glacial maximum across the Weichselian deglaciation to the Holocene. During glacial times, the total foraminifera accumulation remains at a very low level (< 100 specimens cm−2 kyr−1) and is dominated by two endofaunal species: Oridorsalis umbonatus (Reuss) and Siphotextularia rolshauseni (Phleger and Parker) and reworked specimens of the genus Elphidium. The following deglaciation period exhibits an increase of the AR of the total fauna at 14 kyr B.P. The species distribution is marked by the last appearance of S. rolshauseni and the first postglacial appearance of suspension feeding Cibicidoides wuellerstorfi (Schwager) 13 kyr B.P. The absolute maximum of benthic foraminiferal AR (2750 spec cm−2 kyr−1 occurred near 9 kyr B.P. at the end of the deglaciation. This maximum also marks the re-appearance of the agglutinating species Cribrostomoides subglobosus (Sars). The post-glacial interval is characterized by a twofold reduction of the total accumulation of benthic foraminifera. The species distribution shows two new species: Ammobaculites agglutinans (d'Orbigny, at 6 kyr B.P.) and Epistominella exigua (Brady, at 3.5 kyr B.P.). The total AR indicates benthic activity during glacial times was at a low level. It was significantly higher during the Holocene with an abrupt increase of benthic foraminiferal abundance from 10 to 9 kyr B.P. The Stepwise re-invasion into the postglacial deep-sea environment maybe related to specific habitat preference.

Beta adrenergic and muscarinic receptors in compensatory cardiac hypertrophy of the adult rat

The beta adrenergic (beta AR) and muscarinic (MR) receptors have been quantitated in parallel, using 125I-pindolol and 3H-quinuclidinylbenzilate, in a model of compensatory left ventricular (LV) hypertrophy (LVH), which developed in rats 4-6 weeks after an abdominal aortic stenosis. Since aortic banding resulted in a pronounced LVH of 62%, the results were expressed both in terms of density (fmol/mg protein) and quantity (fmol per LV). In addition, competition curves using either a specific beta 1-antagonist or isoproterenol or carbachol allowed the determination of the two beta AR subtypes and of the low and high affinity sites (defined by the inhibitory constant Ki) for both beta 1AR and MR. In LVH, receptor density decreased for each of total beta AR, beta 1AR subtype, high affinity (Ki 6-8 nM) beta 1AR sites (from 26 +/- 2 to 19 +/- 3 fmol/mg protein, P < 0.05), total MR and high affinity (Ki 12 nM) MR sites (from 63 +/- 6 to 40 +/- 4 fmol/mg protein, P < 0.001). The beta AR and MR densities dropped in parallel so that the MR/beta AR ratio remained unchanged. In sharp contrast (because the LVs were bigger) the quantities of total beta AR, beta 1AR subtype, beta 1AR high affinity sites, total MR and MR high affinity sites per LV were unmodified.(ABSTRACT TRUNCATED AT 250 WORDS)

Arthrography: past, present, and future.

Technological advances in arthroscopy and the imaging techniques of sonography, CT, and surface-coil MR have had a substantial impact on conventional arthrographic procedures in the past decade. An individual’s perception of the usefulness of arthrography is influenced by personal interests and those of orthopedic colleagues, referral patterns, access to newer imaging techniques, and recently published data. A survey was done to assess the current and future status of arthrography in relationship to its past use. A questionnaire was sent to 1 46 radiologists who were interested in arthrography. Replies were received from 67% (98/146). The respondents, almost two-thirds of whom were members of the International Skeletal Society, were from 13 countries; 77% (75/98) practiced in the United States or Canada. Seventy-eight percent (76/98) considered their practice to be primarily academic, 1 6% (1 6/98) were hospitalbased nonacademic radiologists, and 6% (6/98) had primarily an office practice. The 98 respondents, representing 92 departments, performed or supervised a total of more than 33,000 arthrograms each year (i.e., for each respondent, 337 per year or six to seven per week). The number of arthrograms performed during the past 5-1 0 years decreased approximately 20% overall; 30% of departments experienced a decrease, and 15% experienced an increase. The decline in examinations was greater in academic centers, perhaps reflecting the fact that arthrography was a relatively new technique 1 0 years ago and was used by fewer private practitioners. Knee examinations accounted for 55% of all arthrograms currently performed. The number of knee studies done during the past 5-1 0 years decreased 50% overall; 85% of respondents experienced a decrease, 1 0% had no change, and only 5% showed an increase. All respondents mentioned arthroscopy as the major factor resulting in this decline. Those practicing in prepaid systems, such as a health maintenance organization or the British Health Service, generally experienced less reduction, and this was attributed to different economic considerations in orthopedic practice. Some arthrographers thought that their only orthopedic referrals were patients with relative contraindications to arthroscopy, such as those who were debilitated, elderly, or overweight; or those who had medicolegal problems or refused arthroscopy. A majority of respondents thought that knee arthrography would continue to decline. A minority thought that continued emphasis on cost containment and the growth of health maintenance organizations would result in a modest increase. A general concern was that arthrography, particularly of the knee, would suffer because of a lack of adequate experience among recent trainees and current radiology residents. Few respondents thought that CT or CT-arthrography would play a significant role in assessment of knee problems in the foreseeable future. On the other hand, noninvasive MR imaging was thought by many to be an excellent technique for assessing the menisci and probably the cruciate ligaments. Those respondents with personal experience in MR imaging of the knee had a throughput of two to three patients per hour and an accuracy that was thought to be almost equivalent to that for arthrography. Some thought that MR imaging, despite its present cost, eventually would replace both arthroscopy and arthrography as the technique of choice for assessment of suspected internal knee injuries. Shoulder arthrograms accounted for 20% of the total ar-

ANDROGEN INSENSITIVITY (AI) IN 43 PATIENTS: CLASSIFICATION BASED ON CLINICAL AND ANDROGEN RECEPTORS (AR) PHENOTYPES

Androgen binding was studied in genital skin fibroblasts (GSF) established from XY patients with testes displaying signs of complete androgen insensitivity syndrome (CAIS, n = 14) and partial AIS (n = 29). Total whole-cell AR concentration (Bmax) in GSF strains derived from 31 normal circumcised boy's was 775 ± 185 × 10−18 mol/μg DNA (mean ± SD). The AR phenotype was receptor-negative in 79% of CAIS patients; however, the remaining 21% in this series had supranormal AR concentrations (mean 1840, range 1541 - 2072 × 10−18 mol/μg DNA). Further studies on these cell strains showed stable androgen binding at 40°C, normal dissociation rate for the AR complex, appropriate GSF cytosol sedimentation on sucrose density gradients in the presence of molybdate and 60% binding of the androgen ligand located in the nuclei. Only 7% of GSF strains from patients with PAIS were AR-negative; mean ± SD concentration of AR in the remainder was 837 ± 315 × 10−18 mol/μg DNA. No PAIS cell strain contained a supranormal AR concentration. More than 90% of AR-positive cell strains (including those with supranormal AR levels) responded by further augmenting total cellular AR concentration following prolonged androgen preincubation of GSF. This AR phenotype is not the result of a mutation affecting the gene coding for the AR protein.

Concentration and cellular distribution of androgen receptor in human prostatic neoplasia: Can estrogen treatment increase androgen receptor content?

The concentration of androgen receptor in cytosol (free and total sites) and nuclear fractions from benign (28 specimens) and malignant prostatic tissue from treated (16 specimens) and untreated patients (10 specimens) were assayed using [ 3H]methyltrienolone ( 3H R-1881) as ligand under conditions which stabilize AR and prevent binding of 3H R-1881 to progesterone receptor. It was found that optimum results were obtained when sodium molybdate (10mM) was added after separation of the nuclear pellet rather than during tissue homogenization; when cytosol and nuclear exchange assays were carried out at 15°C rather than at 0°C; and when hydroxylapatite was used to separate free and bound steroid in the nuclear assay. Although AR values were variable in both BPH and carcinoma tissue, certain patterns of concentration, occupancy, and cellular distribution were observed in different patient groups. In BPH and untreated carcinoma tissue, the mean occupancy of cytosol AR by endogenous androgens was high, but the mean nuclear AR concentration was higher in BPH than in carcinoma tissue. Androgen receptor concentrations in tissue from orchiectomized patients were consistent with the effects of androgen deprivation: total cell AR was depleted, and a higher proportion was present as free cytosol AR. However, in tissue from most patients who had been treated with diethylstilbestrol (DES) on a long-term basis, total cell AR values were high. Although most of the AR was present as free cytosol AR, in three of four patients who had been treated with both orchiectomy and DES, the concentrations of bound cytosol AR and nuclear AR were similar to those in untreated patients.

The effect of therapy on the concentration and occupancy of androgen receptors in human prostatic cytosol.

With a protamine sulphate precipitation method, total and free cytosol AR was assayed in BPH and prostatic carcinoma tissue, in order to investigate possible differences in AR concentration that might relate to the histo-pathology of the tissue or to endocrine manipulation of the patients. Similar ranges of total cytosol AR concentrations were observed in BPH and untreated prostatic carcinoma, but the latter tended to have a higher proportion of apparently free sites. Moreover, the proportion of "free" sites in the untreated carcinoma tissue appeared to be related to the proportion of poorly differentiated carcinoma in the specimen. In patients whose endogenous androgen levels had been lowered by treatment, the proportion of free sites tended to be higher, but a considerable proportion of sites appeared to be still occupied. Carcinoma tissue from some estrogen-treated patients had high cytosol AR concentrations. It is suggested that, in some treated patients, androgens of adrenal origin may occupy some AR sites and that some carcinomas may contain a considerable concentration of nonfunctional AR.