Bilateral renal angiomyolipomas with invasion of the renal vein: A case report

An angiomyolipoma (AML) is usually a benign, rare, and, more commonly, a unilateral renal tumour. Bilateral tumours are very rare, particularly in the absence of tuberous sclerosis complex. Only in a few isolated cases have features of malignancy been associated with an AML. We present a unique case of bilateral AMLs mimicking invasive tumours in the absence of any other features of tuberous sclerosis complex

Lyman Break Galaxies Under a Microscope: The Small Scale Dynamics and Mass of an Arc in the Cluster 1E0657-56

Using the near-infrared integral-field spectrograph SPIFFI on the VLT, we have studied the spatially-resolved dynamics in the z=3.2 strongly lensed galaxy 1E0657-56 ``arc+core''. The lensing configuration suggests that the high surface brightness ``core'' is the M=20 magnified central 1 kpc of the galaxy (seen at a spatial resolution of about 200 pc in the source plane), whereas the fainter ``arc'' is a more strongly magnified peripheral region of the same galaxy at about a half-light radius, which otherwise appears to be a typical z=3 Lyman break galaxy. The overall shape of the position-velocity diagram resembles the ``rotation curves'' of the inner few kpcs of nearby L* spiral galaxies. The projected velocities rise rapidly to 75 km/s within the core. This implies a dynamical mass of M_dyn = 10^9.3 M_sun within the central kpc, and suggests that in this system the equivalent of the mass of a present-day L* bulge at the same radius was already in place by z>=3. Approximating the circular velocity of the halo by the measured asymptotic velocity of the rotation curve, we estimate a dark matter halo mass of M_halo = 10^11.7 +/- 0.3, in good agreement with large-scale clustering studies of Lyman break galaxies. The baryonic collapse fraction is low compared to actively star-forming ``BX'' and low-redshift galaxies around z=2, perhaps implying comparatively less gas infall to small radii or efficient feedback. Even more speculatively, the high central mass density might indicate highly dissipative gas collapse in very early stages of galaxy evolution, in approximate agreement with what is expected for ``inside-out'' galaxy formation models.Comment: Accepted for publication in the Astrophysical Journa

Calcium confusion--is the variability in calcium response by Sertoli cells to specific hormones meaningful or simply redundant?

When results of more than ten different studies on hormone-induced calcium signals in Sertoli cells are taken together, a wide variety of responses emerges. The reported changes range from increased concentrations, via no response at all, to decreased calcium concentrations. Minor variations in cell isolation techniques, culture conditions, or techniques for measuring the intracellular calcium could explain some of these differences. However, erratic variations in response are also observed within research groups under very similar experimental conditions. Such 'negative' findings are mainly reported orally and do not further penetrate the scientific community. As hormone-dependent calcium responses evidently may depend very much on the context of the cells, calcium transients would appear to be unreliable bioassay principles with which to detect the primary actions of FSH and effectors such as androgens on Sertoli cells. A more important biological question is whether these sometimes opposed calcium transients are connected with a particular cellular response. To date there is no evidence for such a tight coupling in Sertoli cells, implying that, at least under in vitro conditions, calcium signals might even be redundant altogether. Such calcium variability is probably not unique to Sertoli cells, and the aim of this commentary is to promote an open debate that may help to transform the current state of 'calcium confusion' into a better understanding of the intracellular calcium language

Use of tamoxifen, an antioestrogen, in establishing a need for oestrogen in early pregnancy in the bonnet monkey (Macaca radiata)

Administration of tamoxifen orally (3 mg/kg/day) during the post-ovulatory period from Days 16 to 20 or from Days 18 to 30 of female bonnet monkeys mated between Days 9 and 14 of the cycle resulted in inhibition of pregnancy establishment in 90-100% of monkeys tested. The pregnancy establishment in control female monkeys after exposure to the male during one ovulatory cycle was 66%. The effect of tamoxifen was not due to interference with luteal function because there was no reduction in serum progesterone concentrations after drug treatment. Exogenously administered progesterone could not reverse the inhibitory effect of tamoxifen on pregnancy establishment. The effect of tamoxifen was dose-dependent. We suggest that tamoxifen could be developed as an effective post-ovulatory contraceptive for regulation of female fertility

Antifertility effect of tamoxifen as tested in the female bonnet monkey (Macaca radiata)

The administration of a potent antiestrogen, tamoxifen at a dose of 3 mg/kg body weight/day orally post-coitally to cycling mated bonnet monkeys(Macaca radiata) from days 18-30 of cycle resulted in inhibition of establishment of pregnancy in 9 out of 10 monkeys. Tamoxifen effect was not due to interference with luteal function. The effect was specific to tamoxifen as exogenously administered progesterone could not reverse it. In addition to suggesting a role for estrogen in maintenance of early pregnancy in the primate the present study could be a prelude to the development of an effective post-ovulatory approach for regulation of fertility in the human female

GMRT mini-survey to search for 21-cm absorption in Quasar-Galaxy Pairs at z~0.1

We present the results from our 21-cm absorption survey of a sample of 5 quasar-galaxy pairs (QGPs), with the redshift of the galaxies in the range 0.03<zg<0.18, selected from the SDSS. The HI 21-cm absorption was searched towards the 9 sight lines with impact parameters ranging from 10 to 55 kpc using GMRT. 21-cm absorption was detected only in one case i.e. towards the Quasar (zq=2.625 SDSS J124157.54+633241.6)-galaxy (zg=0.143 SDSS J124157.26+633237.6) pair with the impact parameter 11 kpc. The quasar sight line in this case pierces through the stellar disk of a galaxy having near solar metallicity (i.e (O/H)+12=8.7) and star formation rate uncorrected for dust attenuation of 0.1 M_odot/yr. The quasar spectrum reddened by the foreground galaxy is well fitted with the Milky Way extinction curve (with an Av of 0.44) and the estimated HI column density is similar to the value obtained from 21-cm absorption assuming spin temperature of 100K. Combining our sample with the z<0.1 data available in the literature, we find the detectability of 21-cm absorption with integrated optical depth greater than 0.1 km\s to be 50% for the impact parameter less than 20 kpc. Using the surface brightness profiles and relationship between the optical size and extent of the HI disk known for nearby galaxies, we conclude that in most of the cases of 21-cm absorption non-detection, the sight lines may not be passing through the HI gas. We also find that in comparison to the absorption systems associated with these QGPs, z<1 DLAs with 21-cm absorption detections have lower CaII equivalent widths despite having higher 21-cm optical depths and smaller impact parameters. This suggests that the current sample of DLAs may be a biased population that avoids sight lines through dusty star-forming galaxies. A systematic survey of QGPs is needed to confirm these findings and understand the nature of 21-cm absorbers.Comment: 17 pages, 5 tables, 19 figures, accepted for publication in MNRAS (abstract abridged