Sporadic, Nontrauma-Related, Desmoid Tumor of the Pancreas: A Rare Disease—Case Report and Literature Review

Desmoid tumors (DTs) are neoplasms of fibroblastic origin characterized by lack of a capsule. They are nonmetastatic and locally aggressive. Intraabdominal DTs are often observed in familial adenomatous polyposis and Gardner syndrome or subsequent to localized traumatic injury. Sporadic forms are defined as nontrauma- or nongenetic-related DTs. Isolated, sporadic pancreatic DTs have been considered anecdotal, with only 9 cases described in the literature. We report the case of a 68-year-old man with a case of sporadic cystic DT localized to the pancreatic tail. The tumor was discovered incidentally during computerized tomography performed for an unrelated condition. The patient was asymptomatic; however, biopsy was performed on the clinical suspicion of cystic cancer of the pancreas. Pathology analysis showed fibroblastic proliferation, and the diagnosis of DT was confirmed by immunohistochemical staining for beta-catenin. The patient underwent resection with no further treatment and remain disease-free 60 months after surgery

Complete repair of dystrophic skeletal muscle by mesoangioblasts with enhanced migration ability

Efficient delivery of cells to target tissues is a major problem in cell therapy. We report that enhancing delivery of mesoangioblasts leads to a complete reconstitution of downstream skeletal muscles in a mouse model of severe muscular dystrophy (α-sarcoglycan ko). Mesoangioblasts, vessel-associated stem cells, were exposed to several cytokines, among which stromal- derived factor (SDF) 1 or tumor necrosis factor (TNF) α were the most potent in enhancing transmigration in vitro and migration into dystrophic muscle in vivo. Transient expression of α4 integrins or L-selectin also increased several fold migration both in vitro and in vivo. Therefore, combined pretreatment with SDF-1 or TNF-α and expression of α4 integrin leads to massive colonization (>50%) followed by reconstitution of >80% of α-sarcoglycan–expressing fibers, with a fivefold increase in efficiency in comparison with control cells. This study defines the requirements for efficient engraftment of mesoangioblasts and offers a new potent tool to optimize future cell therapy protocols for muscular dystrophies

Observational hints of radial migration in disc galaxies from CALIFA

Context. According to numerical simulations, stars are not always kept at their birth galactocentric distances but they have a tendency to migrate. The importance of this radial migration in shaping galactic light distributions is still unclear. However, if radial migration is indeed important, galaxies with different surface brightness (SB) profiles must display differences in their stellar population properties. Aims: We investigate the role of radial migration in the light distribution and radial stellar content by comparing the inner colour, age, and metallicity gradients for galaxies with different SB profiles. We define these inner parts, avoiding the bulge and bar regions and up to around three disc scale lengths (type I, pure exponential) or the break radius (type II, downbending; type III, upbending). Methods: We analysed 214 spiral galaxies from the CALIFA survey covering different SB profiles. We made use of GASP2D and SDSS data to characterise the light distribution and obtain colour profiles of these spiral galaxies. The stellar age and metallicity profiles were computed using a methodology based on full-spectrum fitting techniques (pPXF, GANDALF, and STECKMAP) to the Integral Field Spectroscopic CALIFA data. Results: The distributions of the colour, stellar age, and stellar metallicity gradients in the inner parts for galaxies displaying different SB profiles are unalike as suggested by Kolmogorov-Smirnov and Anderson-Darling tests. We find a trend in which type II galaxies show the steepest profiles of all, type III show the shallowest, and type I display an intermediate behaviour. Conclusions: These results are consistent with a scenario in which radial migration is more efficient for type III galaxies than for type I systems, where type II galaxies present the lowest radial migration efficiency. In such a scenario, radial migration mixes the stellar content, thereby flattening the radial stellar properties and shaping different SB profiles. However, in light of these results we cannot further quantify the importance of radial migration in shaping spiral galaxies, and other processes, such as recent star formation or satellite accretion, might play a role

Physics of ULIRGs with MUSE and ALMA: The PUMA project: III. Incidence and properties of ionised gas disks in ULIRGs, associated velocity dispersion, and its dependence on starburstiness

CONTEXT: A classical scenario suggests that ultra-luminous infrared galaxies (ULIRGs) transform colliding spiral galaxies into a spheroid-dominated early-type galaxy. Recent high-resolution simulations have instead shown that, under some circumstances, rotation disks can be preserved during the merging process or rapidly regrown after coalescence. Our goal is to analyse in detail the ionised gas kinematics in a sample of ULIRGs to infer the incidence of gas rotational dynamics in late-stage interacting galaxies and merger remnants. AIMS: We analysed integral field spectrograph MUSE data of a sample of 20 nearby (z < 0.165) ULIRGs (with 29 individual nuclei) as part of the Physics of ULIRGs with MUSE and ALMA (PUMA) project. We used multi-Gaussian fitting techniques to identify gaseous disk motions and the 3D-Barolo tool to model them. METHODS: We found that 27% (8 out of 29) individual nuclei are associated with kiloparsec-scale disk-like gas motions. The rest of the sample displays a plethora of gas kinematics, dominated by winds and merger-induced flows, which makes the detection of rotation signatures difficult. On the other hand, the incidence of stellar disk-like motions is ∼2 times larger than gaseous disks, as the former are probably less affected by winds and streams. The eight galaxies with a gaseous disk present relatively high intrinsic gas velocity dispersion (σ0 ∈ [30 − 85] km s−1), rotationally supported motions (with gas rotation velocity over velocity dispersion vrot/σ0 ∼ 1 − 8), and dynamical masses in the range (2 − 7)×1010 M⊙. By combining our results with those of local and high-z disk galaxies (up to z ∼ 2) from the literature, we found a significant correlation between σ0 and the offset from the main sequence (δMS), after correcting for their evolutionary trends. RESULTS: Our results confirm the presence of kiloparsec-scale rotating disks in interacting galaxies and merger remnants in the PUMA sample, with an incidence going from 27% (gas) to ≲50% (stars). Their gas σ0 is up to a factor of ∼4 higher than in local normal main sequence galaxies, similar to high-z starbursts as presented in the literature; this suggests that interactions and mergers enhance the star formation rate while simultaneously increasing the velocity dispersion in the interstellar medium

Probing the Star Formation Main Sequence down to 10810^{8} M⊙_\odot at 1.0<z<3.01.0<z<3.0

We investigate the star formation main sequence (MS) (SFR-M$_{\star}$) down to 10$^{8-9}\mathrm{M}_\odot$ using a sample of 34,061 newly-discovered ultra-faint ($27\lesssim i \lesssim 30$ mag) galaxies at $1<z<3$ detected in the GOODS-N field. Virtually these galaxies are not contained in previous public catalogs, effectively doubling the number of known sources in the field. The sample was constructed by stacking the optical broad-band observations taken by the HST/GOODS-CANDELS surveys as well as the 25 ultra-deep medium-band images gathered by the GTC/SHARDS project. Our sources are faint (average observed magnitudes $\sim28.2$ mag, $\sim27.9$ mag), blue (UV-slope $\sim-1.9$), star-forming (rest-frame colors $\sim0.10$ mag, $\sim0.17$ mag) galaxies. These observational characteristics are identified with young (mass-weighted age $\sim0.014$ Gyr) stellar populations subject to low attenuations ($\sim0.30$ mag). Our sample allows us to probe the MS down to $10^{8.0}\,\mathrm{M}_\odot$ at $z=1$ and $10^{8.5}\,\mathrm{M}_\odot$ at $z=3$, around 0.6 dex deeper than previous analysis. In the low-mass galaxy regime, we find an average value for the slope of 0.97 at $1<z<2$ and 1.12 at $2<z<3$. Nearly $\sim$60% of our sample presents stellar masses in the range $10^{6-8}$ M$_\odot$ between $1<z<3$. If the slope of the MS remained constant in this regime, the sources populating the low-mass tail of our sample would qualify as starburst galaxies.Comment: 34 pages, 16 figures, 9 tables. Accepted for publication to Ap

The PUMA project. III. Incidence and properties of ionised gas disks in ULIRGs, associated velocity dispersion and its dependence on starburstiness

A classical scenario suggests that ULIRGs transform colliding spiral galaxies into a spheroid dominated early-type galaxy. Recent high-resolution simulations have instead shown that, under some circumstances, rotation disks can be preserved during the merging process or rapidly regrown after coalescence. Our goal is to analyze in detail the ionised gas kinematics in a sample of ULIRGs to infer the incidence of gas rotational dynamics in late-stage interacting galaxies and merger remnants. We analysed MUSE data of a sample of 20 nearby (z<0.165) ULIRGs, as part of the "Physics of ULIRGs with MUSE and ALMA" (PUMA) project. We found that 27% individual nuclei are associated with kpc-scale disk-like gas motions. The rest of the sample displays a plethora of gas kinematics, dominated by winds and merger-induced flows, which make the detection of rotation signatures difficult. On the other hand, the incidence of stellar disk-like motions is ~2 times larger than gaseous disks, as the former are probably less affected by winds and streams. The eight galaxies with a gaseous disk present relatively high intrinsic gas velocity dispersion (sigma = 30-85 km/s), rotationally-supported motions (with gas rotation velocity over velocity dispersion vrot/sigma > 1-8), and dynamical masses in the range (2-7)x1e10 Msun. By combining our results with those of local and high-z disk galaxies from the literature, we found a significant correlation between sigma and the offset from the main sequence (MS), after correcting for their evolutionary trends. Our results confirm the presence of kpc-scale rotating disks in interacting galaxies and merger remnants, with an incidence going from 27% (gas) to ~50% (stars). The ULIRGs gas velocity dispersion is up to a factor of ~4 higher than in local normal MS galaxies, similar to high-z starbursts as presented in the literature

The Fornax3D project: Environmental effects on the assembly of dynamically cold disks in Fornax cluster galaxies

We apply a population-orbit superposition method to 16 galaxies in the Fornax cluster observed with MUSE/VLT in the context of the Fornax3D project. By fitting the luminosity distribution, stellar kinematics, and age and metallicity maps simultaneously, we obtained the internal stellar orbit distribution, as well as the age and metallicity distribution of stars on different orbits for each galaxy. Based on the model, we decompose each galaxy into a dynamically cold disk (orbital circularity $\lambda_z\ge0.8$) and a dynamically hot non-disk component (orbital circularity $\lambda_z<0.8$), and obtain the surface-brightness, age, and metallicity radial profiles of each component. The galaxy infall time into the cluster is strongly correlated with galaxy cold-disk age with older cold disks in ancient infallers. We quantify the infall time $t_{\rm infall}$ of each galaxy with its cold-disk age using a correlation calibrated with TNG50 cosmological simulations. For galaxies in the Fornax cluster, we found that the luminosity fraction of cold disk in galaxies with $t_{\rm infall}>8$ Gyr are a factor of $\sim 4$ lower than in more recent infallers while controlling for total stellar mass. Nine of the 16 galaxies have spatially extended cold disks, and most of them show positive or zero age gradients; stars in the inner disk are $\sim 2-5$ Gyr younger than that in the outer disk, in contrast to the expectation of inside-out growth. Our results indicate that the assembly of cold disks in galaxies is strongly affected by their infall into clusters, by either removal of gas in outer regions or even tidally stripping or heating part of the pre-existing disks. Star formation in outer disks can stop quickly after the galaxy falls into the cluster, while star formation in the inner disks can last for a few Gyrs more, building the positive age gradient measured in cold disks.Comment: 31 pages, 32 figures, Accepted to A&

Delving deep: a population of extremely dusty dwarfs observed by JWST

We take advantage of the NIRCam photometric observations available as part of the Cosmic Evolution Early Release Science survey (CEERS) to identify and analyse very red sources in an effort to discover very dusty star forming galaxies. We select red galaxies as objects with a S/N>3 at 4.4 $\mu$m and a S/N<2 in all JWST and HST filters at $\lambda\leq2\mu$m, which corresponds to [F200W]-[F444W]>1.2 considering CEERS depths. This selection is ideal to identify very dusty (Av>1 mag) galaxies with stellar masses between $10^6$ to $10^{10}\, \rm M_{\odot}$ at z<5, more massive dusty galaxies at z=5-18 and galaxies at z>18 due to the Lyman absorption, independently of their dust extinction. Our sample of F200W-dropouts contains no strong candidates at z>6.5, instead it consists almost completely (~81%) of z<2 low-mass galaxies, with a median stellar mass of $10^{7.3} \rm M_{\odot}$. These galaxies show an exceptional dust extinction with median value of Av=4.9 mag, completely unexpected given their low stellar mass. The remaining galaxies, which are at z1), but they are generally more massive $>10^{7.5}\rm M_{\odot}$.Comment: 30 pages, 1 table, 19 figures, accepted for publication in A&

Expectations of the size evolution of massive galaxies at 3≤z≤63 \leq z \leq 6 from the TNG50 simulation: the CEERS/JWST view

We present a catalog of about 25,000 images of massive ($M_{\star} \ge 10^9 M_{\odot}$) galaxies at redshift $3 \leq z \leq 6$ from the TNG50 cosmological simulation, tailored for observations at multiple wavelengths carried out with JWST. The synthetic images were created with the SKIRT radiative transfer code, including the effects of dust attenuation and scattering. The noiseless images were processed with the mirage simulator to mimic the Near Infrared Camera (NIRCam) observational strategy (e.g., noise, dithering pattern, etc.) of the Cosmic Evolution Early Release Science (CEERS) survey. In this paper, we analyze the predictions of the TNG50 simulation for the size evolution of galaxies at $3 \leq z \leq 6$ and the expectations for CEERS to probe that evolution. In particular, we investigate how sizes depend on wavelength, redshift, mass, and angular resolution of the images. We find that the effective radius accurately describes the three-dimensional half-mass radius of TNG50 galaxies. Sizes observed at 2~$\mu$m are consistent with those measured at 3.56~$\mu$m at all redshifts and masses. At all masses, the population of higher-$z$ galaxies is more compact than their lower-$z$ counterparts. However, the intrinsic sizes are smaller than the mock observed sizes for the most massive galaxies, especially at $z \lesssim 4$. This discrepancy between the mass and light distribution may point to a transition in the galaxy morphology at $z$=4-5, where massive compact systems start to develop more extended stellar structures.Comment: Accepted for publication in ApJ (20 pages, 12 figures). Data publicly released at https://www.tng-project.org/costantin22 and at https://www.lucacostantin.com/OMEG