367 research outputs found
Stellar masses and disk properties of Lupus young stellar objects traced by velocity-aligned stacked ALMA 13CO and C18O spectra
In recent ALMA surveys, the gas distributions and velocity structures of most
of the protoplanetary disks can still not be imaged at high S/N due to the
short integration time. In this work, we re-analyzed the ALMA 13CO (3-2) and
C18O (3-2) data of 88 young stellar objects in Lupus with the velocity-aligned
stacking method to enhance S/N and to study the kinematics and disk properties
traced by molecular lines. This method aligns spectra at different positions in
a disk based on the projected Keplerian velocities at their positions and then
stacks them. This method enhances the S/N ratios of molecular-line data and
allows us to obtain better detections and to constrain dynamical stellar masses
and disk orientations. We obtain 13CO detections in 41 disks and C18O
detections in 18 disks with 11 new detections in 13CO and 9 new detections in
C18O after applying the method. We estimate the disk orientations and the
dynamical stellar masses from the 13CO data. Our estimated dynamical stellar
masses correlate with the spectroscopic stellar masses, and in a subsample of
16 sources, where the inclination angles are better constrained, the two masses
are in a good agreement within the uncertainties and with a mean difference of
0.15 Msun. With more detections of fainter disks, our results show that high
gas masses derived from the 13CO and C18O lines tend to be associated with high
dust masses estimated from the continuum emission. Nevertheless, the scatter is
large (0.9 dex), implying large uncertainties in deriving the disk gas mass
from the line fluxes. We find that with such large uncertainties it is expected
that there is no correlation between the disk gas mass and the mass accretion
rate with the current data. Deeper observations to detect disks with gas masses
<1E-5 Msun in molecular lines are needed to investigate the correlation between
the disk gas mass and the mass accretion rate.Comment: Submitted to A&
Long-term follow-up of Philadelphia chromosome-positive (Ph+) chronic myeloid leukaemia (CML) in children and adolescents managed at a single institution over a 20-year period
Chronic myeloid leukaemia (CML) is rare in childhood. In our Institution we managed 30 consecutive Ph+CML patients aged <18 years, according to our adults’ guidelines. Patients with HLA-identical related donor (RD) underwent stem cell transplant (SCT). Since 1989, patients without RD were systematically treated with -interferon (IFN) (median dosage: 6 MU/day). Of 18/19 evaluable patients, 17 (94.5%) achieved haematologic response (HR), 11/17 (65%) cytogenetic response (CyR), complete (CCyR) in 4 (23.5%). Three patients remain in CCyR, 2 achieved BCR-ABL transcript disappearance. Of 13 patients without CCyR, 5 underwent SCT, 4 switched to STI571, 4 progressed. All patients receiving STI571 in chronic phase (CP) obtained sustained CCyR and 3 a persistent molecular response. 8-year survival among IFN-treated patients, censored or not for subsequent therapies, is 62% and 63%. Overall, 13/30 patients underwent SCT: 5 HLA-identical-RD, 5 matched unrelated donor, 2 mismatched-RD, 1 unrelated mismatched umbilical cord blood. Eight allotransplanted patients (6/6 in 1st CP) are in cytogenetic and molecular remission with 8-year survival of 61% from SCT and 69% from diagnosis.
In our 20-year experience, the use of IFN in children without matched RD led to prolonged cytogenetic and molecular responses and long-term survival, without impairing the outcome of subsequent SCT
Can patients with epilepsy become bone marrow donors? A case report of allogeneic hematopoietic stem transplantation from child with seizures
Hematopoietic stem cell (HSC) transplantation is an important treatment option for malignant and non-malignant hematopoietic disorder in adults and children. For long time epilepsy was temporary exclusion condition to voluntary donation, and donors had to be medication or seizure free. It is still unclear if people with history of epilepsy are indeed potential eligible donors, even if a significant increased risk of adverse events in these donors has not been demonstrated. We studied a 10-year-old boy with symptomatic focal epilepsy who was the only available donor for his monozycote twin, suffering from acute lymphoblastic leukemia. A total of 3.39 x 108/kg HSCs were collected and reinfused to the leukemic brother after conditioning treatment. At the end of follow-up, our epilepsy patient had no consequences and his brother is in complete remission of the disease at 3 years from the transplant procedure. Our observation confirms that a patient with epilepsy can be a donor, without consequences for himself and for the recipient
An ALMA Survey of Protoplanetary Disks in the Orionis Cluster
The Orionis cluster is important for studying protoplanetary disk
evolution, as its intermediate age (3-5 Myr) is comparable to the median
disk lifetime. We use ALMA to conduct a high-sensitivity survey of dust and gas
in 92 protoplanetary disks around Orionis members with
. Our observations cover the 1.33 mm continuum
and several CO lines: out of 92 sources, we detect 37 in the mm
continuum and six in CO, three in CO, and none in CO.
Using the continuum emission to estimate dust mass, we find only 11 disks with
, indicating that after only a few Myr of
evolution most disks lack sufficient dust to form giant planet cores. Stacking
the individually undetected continuum sources limits their average dust mass to
5 lower than that of the faintest detected disk, supporting theoretical
models that indicate rapid dissipation once disk clearing begins. Comparing the
protoplanetary disk population in Orionis to those of other
star-forming regions supports the steady decline in average dust mass and the
steepening of the - relation with age; studying these
evolutionary trends can inform the relative importance of different disk
processes during key eras of planet formation. External photoevaporation from
the central O9 star is influencing disk evolution throughout the region: dust
masses clearly decline with decreasing separation from the photoionizing
source, and the handful of CO detections exist at projected separations
pc. Collectively, our findings indicate that giant planet formation is
inherently rare and/or well underway by a few Myr of age.Comment: 16 pages, 9 figures; published in AJ; The full machine readable
tables can be obtained by downloading and extracting the gzipped tar source
file listed under "Other formats.
Subcellular localization of the five members of the human steroid 5α-reductase family
In humans the steroid 5a-reductase (SRD5A) family comprises five integral membrane enzymes that carry out reduction of a double bond in
lipidic substrates: D4-3-keto steroids, polyprenol and trans-enoyl CoA. The best-characterized reaction is the conversion of testosterone into the
more potent dihydrotestosterone carried out by SRD5A1-2. Some controversy exists on their possible nuclear or endoplasmic reticulum
localization.
We report the cloning and transient expression in HeLa cells of the five members of the human steroid 5a-reductase family as both N- and Cterminus
green fluorescent protein tagged protein constructs. Following the intrinsic fluorescence of the tag, we have determined that the
subcellular localization of these enzymes is in the endoplasmic reticulum, upon expression in HeLa cells. The presence of the tag at either end of
the polypeptide chain can affect protein expression and, in the case of trans enoyl-CoA reductase, it induces the formation of protein aggregates
Metabolomics as a Powerful Tool for Molecular Quality Assessment of the Fish Sparus aurata
The molecular profiles of perchloric acid solutions extracted from the flesh of Sparus aurata fish specimens, produced according to different aquaculture systems, have been investigated. The 1H-NMR spectra of aqueous extracts are indicative of differences in the metabolite content of fish reared under different conditions that are already distinguishable at their capture, and substantially maintain the same differences in their molecular profiles after sixteen days of storage under ice. The fish metabolic profiles are studied by top-down chemometric analysis. The results of this exploratory investigation show that the fish metabolome accurately reflects the rearing conditions. The level of many metabolites co-vary with the rearing conditions and a few metabolites are quantified including glycogen (stress indicator), histidine, alanine and glycine which all display significant changes dependent on the aquaculture system and on the storage times
New insights into the nature of transition disks from a complete disk survey of the Lupus star forming region
Transition disks with large dust cavities around young stars are promising
targets for studying planet formation. Previous studies have revealed the
presence of gas cavities inside the dust cavities hinting at recently formed,
giant planets. However, many of these studies are biased towards the brightest
disks in the nearby star forming regions, and it is not possible to derive
reliable statistics that can be compared with exoplanet populations. We present
the analysis of 11 transition disks with large cavities (>20 AU radius) from a
complete disk survey of the Lupus star forming region, using ALMA Band 7
observations at 0.3" (22-30 AU radius) resolution of the 345 GHz continuum,
13CO and C18O 3-2 observations and the Spectral Energy Distribution of each
source. Gas and dust surface density profiles are derived using the
physical-chemical modeling code DALI. This is the first study of transition
disks of large cavities within a complete disk survey within a star forming
region. The dust cavity sizes range from 20-90 AU radius and in three cases, a
gas cavity is resolved as well. The deep drops in gas density and large dust
cavity sizes are consistent with clearing by giant planets. The fraction of
transition disks with large cavities in Lupus is ~11%, which is inconsistent
with exoplanet population studies of giant planets at wide orbits. Furthermore,
we present a hypothesis of an evolutionary path for large massive disks
evolving into transition disks with large cavities.Comment: 29 pages, 15 figures, Accepted by Ap
Twenty years of the Italian Fanconi Anemia Registry: where we stand and what remains to be learned
The natural history of Fanconi anemia remains hard to establish because of its rarity and its heterogeneous clinical presentation; since 1994, the Italian Fanconi Anemia Registry has collected clinical, epidemiological and genetic data of Italian Fanconi Anemia patients. This registry includes 180 patients with a confirmed diagnosis of Fanconi anemia who have either been enrolled prospectively, at diagnosis, or later on. After enrollment, follow-up data were periodically collected to assess the clinical course, possible complications and long-term survival; the median follow up was 15.6 years. The main goal of the study was to describe the natural history of Fanconi anemia, focusing on the following variables: family history, disease presentation, development of hematological manifestations, development of malignancies, occurrence of hematopoietic stem cell transplantation and survival. Typical morphological and/or hematological abnormalities and/or growth retardation were the most common manifestations at diagnosis; the majority of patients (77%) exhibited hematological abnormalities at the initial presentation, and almost all (96%) eventually developed hematological manifestations. More than half of the patients (57%) underwent a bone-marrow transplant. The occurrence of cancer was quite rare at diagnosis, whereas the cumulative incidence of malignancies at 10, 20 and 30 years was 5%, 8% and 22%, respectively, for hematological cancers and 1%, 15% and 32%, respectively, for solid tumors. Overall survival at 10, 20 and 30 years were 88%, 56% and 37%, respectively; the main causes of death were cancer, complications of the hematological presentation and complications of transplantation. These data clearly confirm the detrimental outcome of Fanconi anemia, with no major improvement in the past decades
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