Human brucellosis in South Africa: Public health and diagnostic pitfalls

Human brucellosis in South Africa (SA) is under-diagnosed and under-reported. This is because many clinicians have little or no experience in managing affected patients, and in part because of the nonspecific and insidious nature of the disease. A case of human brucellosis caused by Brucella melitensis in a patient from the Western Cape Province of SA is described, and the resulting exposure of staff members at two medical microbiology laboratories, as well as the public health investigation that was conducted, are discussed. The objective of this article is to highlight the need for strengthening integration between public health, medical and veterinary services and exposing deficiencies in public health, veterinary and laboratory practices

Generalized Lévy walks and the role of chemokines in migration of effector CD8+ T cells.

Chemokines have a central role in regulating processes essential to the immune function of T cells, such as their migration within lymphoid tissues and targeting of pathogens in sites of inflammation. Here we track T cells using multi-photon microscopy to demonstrate that the chemokine CXCL10 enhances the ability of CD8+ T cells to control the pathogen Toxoplasma gondii in the brains of chronically infected mice. This chemokine boosts T-cell function in two different ways: it maintains the effector T-cell population in the brain and speeds up the average migration speed without changing the nature of the walk statistics. Notably, these statistics are not Brownian; rather, CD8+ T-cell motility in the brain is well described by a generalized Lévy walk. According to our model, this unexpected feature enables T cells to find rare targets with more than an order of magnitude more efficiency than Brownian random walkers. Thus, CD8+ T-cell behaviour is similar to Lévy strategies reported in organisms ranging from mussels to marine predators and monkeys, and CXCL10 aids T cells in shortening the average time taken to find rare targets

Preparation of symmetrical and non-symmetrical fluorene sulfonamide scaffolds

Methods for the preparation of symmetrical and non-symmetrical 2,7-disubstituted 9H-fluorene derivatives are described

Synthesis of dibenzylamino-1-methylcyclohexanol and dibenzylamino-1-trifluoromethylcyclohexanol isomers

The isomers of dibenzylamino-1-methylcyclohexan-1-ol and dibenzylamino-1-trifluoromethylcyclohexan-1-ol have been prepared. The stereochemistry of these compounds was unequivocally assigned through a combination of NMR spectroscopy and single crystal X-ray analysis. The cis-isomer of 3-N,N-dibenzylamino-1-trifluoromethylcyclohexanol and its derivatives display an unusual conformational behaviour in both solution-phase and the solid-state, where the amino group usually adopts an axial conformation

Resolved SPLASH Chemodynamics in Andromeda's PHAT Stellar Halo and Disk: On the Nature of the Inner Halo Along the Major Axis

Stellar kinematics and metallicity are key to exploring formation scenarios for galactic disks and halos. In this work, we characterized the relationship between kinematics and photometric metallicity along the line-of-sight to M31's disk. We combined optical HST/ACS photometry from the Panchromatic Hubble Andromeda Treasury (PHAT) survey with Keck/DEIMOS spectra from the Spectroscopic and Photometric Landscape of Andromeda's Stellar Halo (SPLASH) survey. The resulting sample of 3536 individual red giant branch stars spans 4-19 projected kpc, making it a useful probe of both the disk and inner halo. We separated these stars into disk and halo populations by modeling the line-of-sight velocity distributions as a function of position across the disk region, where 70.9% stars have a high likelihood of belonging to the disk and 17.1% to the halo. Although stellar halos are typically thought to be metal-poor, the kinematically identified halo contains a significant population of stars (29.4%) with disk-like metallicity ([Fe/H]$_{\rm phot} \sim -0.10$). This metal-rich halo population lags the gaseous disk to a similar extent as the rest of the halo, indicating that it does not correspond to a canonical thick disk. Its properties are inconsistent with those of tidal debris originating from the Giant Stellar Stream merger event. Moreover, the halo is chemically distinct from the phase-mixed component previously identified along the minor axis (i.e., away from the disk), implying contributions from different formation channels. These metal-rich halo stars provide direct chemodynamical evidence in favor of the previously suggested "kicked-up'' disk population in M31's inner stellar halo.Comment: Submitted to AJ. Conclusions on page 20. 18 figures, 2 tables, 4 appendice

Elemental abundances in M31: Individual and Coadded Spectroscopic [Fe/H] and [{\alpha}/Fe] throughout the M31 Halo with SPLASH

We present spectroscopic chemical abundances of red giant branch (RGB) stars in Andromeda (M31), using medium resolution ($R\sim6000$) spectra obtained via the Spectroscopic and Photometric Landscape of Andromeda's Stellar Halo (SPLASH) survey. In addition to individual chemical abundances, we coadd low signal-to-noise ratio (S/N) spectra of stars to obtain a high enough to measure average [Fe/H] and [$\alpha$/Fe] abundances. We obtain individual and coadded measurements for [Fe/H] and [$\alpha$/Fe] for M31 halo stars, covering a range of 9--180 kpc in projected radius from the center of M31. With these measurements, we greatly increase the number of outer halo ($R_{\mathrm{proj}} > 50$ kpc) M31 stars with spectroscopic [Fe/H] and [$\alpha$/Fe], adding abundance measurements for 45 individual stars and 33 coadds from a pool of an additional 174 stars. We measure the spectroscopic metallicity ([Fe/H]) gradient, finding a negative radial gradient of $-0.0050\pm0.0003$ for all stars in the halo, consistent with gradient measurements obtained using photometric metallicities. Using the first measurements of [$\alpha$/Fe] for M31 halo stars covering a large range of projected radii, we find a positive gradient ($+0.0026\pm0.0004$) in [$\alpha$/Fe] as a function of projected radius. We also explore the distribution in [Fe/H]--[$\alpha$/Fe] space as a function of projected radius for both individual and coadded measurements in the smooth halo, and compare these measurements to those stars potentially associated with substructure. These spectroscopic abundance distributions highlight the substantial evidence that M31 has had an appreciably different formation and merger history compared to our own Galaxy.Comment: Submitted to Ap

Identification of Globular Cluster Stars in RAVE data II: Extended tidal debris around NGC 3201

We report the identification of extended tidal debris potentially associated with the globular cluster NGC 3201, using the RAdial Velocity Experiment (RAVE) catalogue. We find the debris stars are located at a distance range of 1–7 kpc based on the forthcoming RAVE distance estimates. The derived space velocities and integrals of motion show interesting connections to NGC 3201, modulo uncertainties in the proper motions. Three stars, which are among the four most likely candidates for NGC 3201 tidal debris, are separated by 80° on the sky yet are well matched by the 12 Gyr, [Fe/H] = −1.5 isochrone appropriate for the cluster. This is the first time tidal debris around this cluster has been reported over such a large spatial extent, with implications for the cluster's origin and dynamical evolution

Decreased galectin-3 expression in prostate cancer

BACKGROUND Galectin-3 is a carbohydrate-binding protein whose level of expression has been shown to be correlated with metastatic potential in a number of different tumor types. The purpose of this investigation was to examine galectin-3 expression in several tumorigenic and nontumorigenic prostate cell lines and prostate tissue samples. METHODS The expression of galectin-3 in cell lines and tissue samples was evaluated by tissue immunohistochemistry and Western blot analysis. RESULTS Human cell lines PC-3M, PC-3, DU-145, PrEC-1, and MCF10A demonstrated the presence of galectin-3. Galectin-3 was not detected in TSU-pr1 and LNCaP by Western blot analysis. We furthered our studies by examining a series of human prostate tissue samples for expression of galectin-3. Overall, approximately 60–70% of the normal tissue examined demonstrated heterogenous expression of galectin-3. In stage II tumors, however, there was a dramatic decrease in galectin-3 expression in both PIN and tumor sections, with only 10.5% (2/19) of these samples expressing this protein. Stage III tumors also demonstrated a decreased expression of galectin-3, although this downregulation was not as dramatic, with 35% of PIN samples and 52% of tumor tissue expressing galectin-3 ( P < 0.01). CONCLUSIONS These data demonstrate that galectin-3 is downregulated in prostate cancer. The altered downregulation pattern of galectin-3 observed between tumor stages suggests different roles for galectin-3 in the progression of prostate cancer. Prostate 44:118–123, 2000. © 2000 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34754/1/4_ftp.pd

CHROMOSPHERICALLY ACTIVE STARS in the RAVE SURVEY. II. YOUNG DWARFS in the SOLAR NEIGHBORHOOD

© 2017. The American Astronomical Society. All rights reserved. A large sample of over 38,000 chromospherically active candidate solar-like stars and cooler dwarfs from the RAVE survey is addressed in this paper. An improved activity identification with respect to the previous study was introduced to build a catalog of field stars in the solar neighborhood with an excess emission flux in the calcium infrared triplet wavelength region. The central result of this work is the calibration of the age-activity relation for main-sequence dwarfs in a range from a few 10 Myr up to a few Gyr. It enabled an order of magnitude age estimation of the entire active sample. Almost 15,000 stars are shown to be younger than 1 Gyr and ∼2000 younger than 100 Myr. The young age of the most active stars is confirmed by their position off the main sequence in the J - K versus N UV - V diagram showing strong ultraviolet excess, mid-infrared excess in the J - K versus W 1 - W 2 diagram, and very cool temperatures (J - K < 0.7). They overlap with the reference pre-main-sequence RAVE stars often displaying X-ray emission. The activity level increasing with the color reveals their different nature from the solar-like stars and probably represents an underlying dynamo-generating magnetic fields in cool stars. Of the RAVE objects from DR5, 50% are found in the TGAS catalog and supplemented with accurate parallaxes and proper motions by Gaia. This makes the database of a large number of young stars in a combination with RAVE's radial velocities directly useful as a tracer of the very recent large-scale star formation history in the solar neighborhood. The data are available online in the Vizier database