411 research outputs found
Treatment of a Severe Pediatric Lyell Syndrome with Amniotic Membrane: Case Report and Histological Findings
Background:
Lyell Syndrome (TEN, Toxic epidermal necrolysis) represents a medical emergency particularly in pediatric patients in whom the massive skin damage can quickly lead to multi-organ dysfunction and death. Prompt restoration of the physiologic mucosal/cutaneous barrier is mandatory. The use of amniotic membranes has been described in the treatment of ophthalmic Lyell Syndrome, but its use has not yet been adopted for the management of larger cutaneous wounds.
Study Hypothesis:
Here we report the use of amniotic membranes in a pediatric case of severe Lyell Syndrome with complete skin surface, ocular and mucosal involvement with life threating presentation.
Methods:
A 7-year old female was admitted to our Burn Centre for severe cutaneous/mucosal exfoliation (100% Total body surface area, TBSA) as a result of an adverse reaction to ibuprofen administration. Supportive fluid administration, cardiac-pulmonary assistance and pain management were complemented by serial grafting of amniotic membranes on all affected areas to provide coverage of the exfoliated skin/mucosa. Biopsies were obtained to monitor histological skin changes.
Results:
The patient showed an excellent response to amniotic membrane treatment, with rapid restoration of mucosal and cutaneous layers in the grafted areas. This resulted in a decreased need for dressing changes, avoidance of additional surgeries and a reduced dependence on supportive therapy. Lower pain levels than usually expected led to a reduced need for narcotic pain medications and allowed for early physical rehabilitation and a short hospital stay. Histology confirmed evidence of topical immune-modulation in treated areas (reduction of inflammatory infiltrate).
Conclusion:
As we tested in numerously TEN and burn pediatric injuries Amniotic membranes with their regenerative and immune-modulatory effects may represent an life saving treatment even in the worst cases of pediatric Lyell syndrome
Giant outburst from the supergiant fast X-ray transient IGR J17544-2619: accretion from a transient disc?
Supergiant fast X-ray transients (SFXTs) are high mass X-ray binaries
associated with OB supergiant companions and characterised by an X-ray flaring
behaviour whose dynamical range reaches 5 orders of magnitude on timescales of
a few hundred to thousands of seconds. Current investigations concentrate on
finding possible mechanisms to inhibit accretion in SFXTs and explain their
unusually low average X-ray luminosity. We present the Swift observations of an
exceptionally bright outburst displayed by the SFXT IGR J17544-2619 on 2014
October 10 when the source achieved a peak luminosity of erg
s. This extends the total source dynamic range to 10, the
largest (by a factor of 10) recorded so far from an SFXT. Tentative evidence
for pulsations at a period of 11.6 s is also reported. We show that these
observations challenge, for the first time, the maximum theoretical luminosity
achievable by an SFXT and propose that this giant outburst was due to the
formation of a transient accretion disc around the compact object.Comment: Accepted for publication in Astronomy and Astrophysics Letters. 5
pages, 5 figures, 2 table
The first Suzaku observation of SGR 1806-20
The soft gamma-ray repeater SGR 1806-20 has been attracting a lot of
attention owing to the fact that in December 2004 it emitted the most powerful
giant flare ever observed. Here we present the results of the first Suzaku
observation of SGR 1806-20, that seems to have reached a state characterized by
a flux close to the pre-flare level and by a relatively soft spectrum. Despite
this, the source remained quite active, as testified by several short bursts
observed by Suzaku. We discuss the broadband spectral properties of SGR 1806-20
in the context of the magnetar model, considering its recent theoretical
developments.Comment: 3 pages, 1 figure. Proceedings of the conference "40 Years of
Pulsars, Millisecond Pulsars, Magnetars and More", Montreal, August 12-17
2007. AIP, in pres
Our distorted view of magnetars: application of the Resonant Cyclotron Scattering model
The X-ray spectra of the magnetar candidates are customarily fitted with an
empirical, two component model: an absorbed blackbody and a power-law. However,
the physical interpretation of these two spectral components is rarely
discussed. It has been recently proposed that the presence of a hot plasma in
the magnetosphere of highly magnetized neutron stars might distort, through
efficient resonant cyclotron scattering, the thermal emission from the neutron
star surface, resulting in the production of non-thermal spectra. Here we
discuss the Resonant Cyclotron Scattering (RCS) model, and present its XSPEC
implementation, as well as preliminary results of its application to Anomalous
X-ray Pulsars and Soft Gamma-ray Repeaters.Comment: 5 pages, 5 color figures; Astrophysics & Space Science, in press
("Isolated Neutron Stars"; London, UK
Magnetar-like X-ray Bursts from an Anomalous X-ray Pulsar
Anomalous X-ray Pulsars (AXPs) are a class of rare X-ray pulsars whose energy
source has been perplexing for some 20 years. Unlike other, better understood
X-ray pulsars, AXPs cannot be powered by rotation or by accretion from a binary
companion, hence the designation ``anomalous.'' AXP rotational and radiative
properties are strikingly similar to those of another class of exotic objects,
the Soft Gamma Repeaters (SGRs). However, the defining property of SGRs, namely
their low-energy gamma-ray and X-ray bursts, have heretofore not been seen in
AXPs. SGRs are thought to be ``magnetars,'' young neutron stars powered by the
decay of an ultra-high magnetic field. The suggestion that AXPs are magnetars
has been controversial. Here we report the discovery, from the direction of AXP
1E 1048-5937, of two X-ray bursts that have many properties similar to those of
SGR bursts. These events imply a close relationship between AXPs and SGRs, with
both being magnetars.Comment: 14 pages, 2 figures, accepted for publication in Nature. Note: The
content of this paper is embargoed until 1900 hrs London time / 1400 US
Eastern Time on Sept 1
SGR 0418+5729: a low-magnetic-field magnetar
Soft gamma-ray repeaters and anomalous X-ray pulsars are a small (but
growing) group of X-ray sources characterized by the emission of short bursts
and by a large variability in their persistent flux. They are believed to be
magnetars, i.e. neutron stars powered by extreme magnetic fields 1E14-1E15 G).
We found evidence for a magnetar with a low magnetic field, SGR 0418+5729,
recently detected after it emitted bursts similar to those of soft gamma-ray
repeaters. New X-ray observations show that its dipolar magnetic field cannot
be greater than 8E12 G, well in the range of ordinary radio pulsars, implying
that a high surface dipolar magnetic field is not necessarily required for
magnetar-like activity. The magnetar population may thus include objects with a
wider range of magnetic-field strengths, ages and evolutionary stages than
observed so far.Comment: 4 pages, 2 figures; to appear in the Proceedings of the Pulsar
Conference 2010, Chia, Sardinia (Italy), 10-15 October 201
A first look with Chandra at SGR 1806-20 after the Giant Flare: significant spectral softening and rapid flux decay
We report on the results of a ~30 ks Chandra pointing of the soft gamma-ray
repeater SGR 1806-20, the first X-ray observation with high spectral resolution
performed after the 2004 December 27 Giant Flare. The source was found in a
bursting active phase and with a significantly softer spectrum than that of the
latest observations before the Giant Flare. The observed flux in the 2-10 keV
range was ~2.2 x10^-11 erg/s/cm^2, about 20% lower than that measured three
months before the event. This indicates that, although its giant flare was ~100
times more intense than those previously observed in two other soft gamma-ray
repeaters, the post flare X-ray flux decay of SGR 1806-20 has been much faster.
The pulsed fraction was about 3%, a smaller value than that observed before the
flare. We discuss the different properties of the post-flare evolution of SGR
1806-20 in comparison to those of SGR 1900+14 and interpret the results as a
strong evidence that a magnetospheric untwisting occurred (or is occurring)
after the Giant Flare.Comment: accepted for publication on ApJ Letter
Anatomical study and clinical implication of perivascular fascia of the radial artery
The characteristics of the fascial tissue that surround a vascular bundle are rarely described in any anatomical textbook and often neglected in the histological description of a vascular structure. The ability of a vascular structure to adapt to any body movement, to maintain its calibre against external pressure preserving its functional role is guarantee by this perivascular fascia. Wrist ganglions are the most common masses localized on the dorsal and volar aspect of the wrist. The herniation of the synovial sac or a split in the synovial epithelium of the volar wrist joint produce a ganglion that is able to distort and compress the radial artery. Authors present the case of 24 years old man with a mucinous cyst originated from the volar wrist joint that was grown inside the vascular fascia of the radial artery and extended up to the middle portion of the forearm. Clinical sintomatology of pain and tenderness was justify by the temporary partial decrease of the arterial lumen and occlusion of the satellite veins. To better understand the clinical relevance of these fascial tissue a microscopical study of serial sections of the radial artery in 20 cadaveric upper limbs was performed (EE, Azan-Mallory, Weigert). The mean area of the perivascular fascia was 13596,3 mm, the mean minimum and maximum thickness of this area was 73 and 389 micron. The mean thickness of the fibrous tissue of the perivascular fascia was 26,21 micron. During the raising of a forearm pedicled radial artery flap or during the surgical excision of volar wrist ganglions the surgeon has to mobilize the radial artery thanks to the integrity of its perivascular fascia. The fascia surrounding the radial artery and satellite veins represented a inestensive sleeve that compelled the mucinous cyst to grow flattened proximally until its complete erniation and superficial radial nerve dislocation in the middle of the forearm. Other clinical implications of the alteration of the radial perivascular fascia are described
Use of adipose derived stem cells in Treacher Collins syndrome
Objective: Treacher Collins syndrome (TCS) is a rare congenital disorder of craniofacial development. TCS occurs with an incidence of 1:50,000, and more than 60% of TCS cases have no previous family history and arise as the result of de novo mutations. The high rate of de novo mutations, together with the extreme variability in the degree to which individuals can be affected, makes the provision of genetic counseling extremely complicated. Consequently, every case of TCS is unique and needs to be assessed individually. Patients with TCS frequently undergo multiple reconstructive surgeries from birth through adulthood, which rarely are fully corrective in the long-term. The nascent field of regenerative medicine offers the promise to improve some of these treatments. In particular, structural fat grafting (SFG) seems to be a good strategy not only to restore the normal volume and contour of the face, but also to provide a source of adipose-derived stem cells (ADSCs) with a multilineage differentiation potential. In this work, we present genetical analyses of ADSC affected by TCS. Materials and methods: ADSCs from were analyzed for their stemness properties and shared many characteristics with those of a healthy subject. Screening of the genome of the TCS patient using array-Comparative Genomic Hybridization allowed us to identify some chromosomal imbalances that are probably associated with TCS. Results: We found that some alterations, involving the TIMELESS gene, were usually associated with embryonic stem cells. Conclusions: With the aim to improve the final results, we need to consider combining knowledge of genetic alterations and expression profiles as a fundamental step before starting with surgical procedures
Structured self-monitoring of blood glucose is associated with more appropriate therapeutic interventions than unstructured self-monitoring: A novel analysis of data from the PRISMA trial
Aims: To investigate the relationship between single therapeutic interventions and indicators of glycemic control in the PRISMA trial, a large study comparing the effects of intensive structured SMBG (ISM) vs. active control (AC) in non-insulin-treated type 2 diabetes (T2D). Methods: Information was collected at four time points, corresponding to months 3, 6, 9, and 12 and visits 2, 3, 4, and 5, respectively. Data on therapeutic interventions, HbA1c levels and the number of hypoglycemic episodes at each visit were analyzed. Results: Intensification of drug therapy occurred in 20.3% vs. 15.6%, and no change in 71.8% vs. 78.7% of visits for the ISM and AC groups, respectively. On the other hand, de-intensification and redistribution of drugs and/or drug dose occurred in a similar proportion of visits. Intensification of drug therapy in both groups was associated with significant reductions in HbA1c vs. the previous visit, while de-intensification of therapy led to a significant increase in HbA1c in the AC group only. Conclusions. Our data strongly support that structured SMBG has clinical value in reducing HbA1c in non-insulin-treated T2D and suggest that this clinical benefit may be mediated by more appropriate and timely changes in drug therapy
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