808 research outputs found
The Changing Presentation of Choledochal Cyst Disease: An Incidental Diagnosis
Background. Choledochal cysts are uncommon biliary lesions. Due to the evolution of imaging and laparoscopic surgery, we sought to describe our last 3 years experience with the presentation and management of choledochal cysts in adults. Methods. A retrospective review of a prospectively established database of adults who were managed for primary choledochal cyst disease between 2005 and 2008 was performed. Results. Between 8/2005 and 8/2008, 14 adults were managed for primary choledochal cyst disease. The average age was 41 years (range 17–86) and 79% were female. Presentations included biliary sepsis (3), pancreatitis (2), abdominal pain (3), or painless jaundice (1). Three patients had the cyst found during laparoscopic cholecystectomy, and two had an incidental finding after CT scan for an unrelated issue. The length of stay for those who had the cyst removed was 7.8 days (range 5–11). There were no operative or post-operative complications. Conclusions. Over the last 3 years 36% of our patients with choledochal cysts presented after incidental finding, either during a laparoscopic operation or after a CT scan for an unrelated problem. Increasing utilization of laparoscopy and CT scan for abdominal complaints has lead to a change in the pattern of presentation
Comparison of Surface Area across the Allograft-Host Junction Site Using Conventional and Navigated Osteotomy Technique.
Bulk allograft reconstruction plays an important role in limb-salvage surgery; however, non-union has been reported in up to 27% of cases. The purpose of this study is to quantify average surface contact areas across simulated intraoperative osteotomies using both free-hand and computer-assisted navigation techniques. Pressure-sensitive paper was positioned between two cut ends of a validated composite sawbone and compression was applied using an eight-hole large fragment dynamic compression plate. Thirty-two samples were analyzed for surface area contact to determine osteotomy congruity. Mean contact area using the free-hand osteotomy technique was equal to 0.21 square inches. Compared with a control of 0.69 square inches, average contact area was found to be 30.5% of optimal surface contact. Mean contact area using computer-assisted navigation was equal to 0.33 square inches. Compared with a control of 0.76 square inches, average contact area was found to be 43.7% of optimal surface contact. Limited contact achieved using standard techniques may play a role in the high rate of observed non-union, and an increase in contact area using computer-assisted navigation may improve rates of bone healing. The development of an oncology software package and navigation hardware may serve an important role in decreasing non-union rates in limb salvage surgery
ASTER, a multinational Earth observing concept
The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is a facility instrument selected for launch in 1998 on the first in a series of spacecraft for NASA's Earth Observing System (EOS). The ASTER instrument is being sponsored and built in Japan. It is a three telescope, high spatial resolution imaging instrument with 15 spectral bands covering the visible through to the thermal infrared. It will play a significant role within EOS providing geological, biological, land hydrological information necessary for intense study of the Earth. The operational capabilities for ASTER, including the necessary interfaces and operational collaborations between the US and Japanese participants, are under development. EOS operations are the responsibility of the EOS Project at NASA's Goddard Space Flight Center (GSFC). Although the primary EOS control center is at GSFC, the ASTER control facility will be in Japan. Other aspects of ASTER are discussed
Epigenetic Mechanism Underlying the Development of Polycystic Ovary Syndrome (PCOS)-Like Phenotypes in Prenatally Androgenized Rhesus Monkeys
The pathogenesis of polycystic ovary syndrome (PCOS) is poorly understood. PCOS-like phenotypes are produced by prenatal androgenization (PA) of female rhesus monkeys. We hypothesize that perturbation of the epigenome, through altered DNA methylation, is one of the mechanisms whereby PA reprograms monkeys to develop PCOS. Infant and adult visceral adipose tissues (VAT) harvested from 15 PA and 10 control monkeys were studied. Bisulfite treated samples were subjected to genome-wide CpG methylation analysis, designed to simultaneously measure methylation levels at 27,578 CpG sites. Analysis was carried out using Bayesian Classification with Singular Value Decomposition (BCSVD), testing all probes simultaneously in a single test. Stringent criteria were then applied to filter out invalid probes due to sequence dissimilarities between human probes and monkey DNA, and then mapped to the rhesus genome. This yielded differentially methylated loci between PA and control monkeys, 163 in infant VAT, and 325 in adult VAT (BCSVD P<0.05). Among these two sets of genes, we identified several significant pathways, including the antiproliferative role of TOB in T cell signaling and transforming growth factor-β (TGF-β) signaling. Our results suggest PA may modify DNA methylation patterns in both infant and adult VAT. This pilot study suggests that excess fetal androgen exposure in female nonhuman primates may predispose to PCOS via alteration of the epigenome, providing a novel avenue to understand PCOS in humans
Thromboembolism After Intramedullary Nailing for Metastatic Bone Lesions.
BACKGROUND: The risk of venous thromboembolism (VTE) in patients undergoing intramedullary nailing for skeletal metastatic disease is currently undefined. The purpose of our study was to determine the risk of thromboembolic events, to define the risk factors for VTE, and to define the rate of wound complications in this population.
METHODS: A retrospective review of surgical databases at three National Cancer Institute (NCI)-designated cancer centers identified 287 patients with a total of 336 impending or pathologic long-bone fractures that were stabilized with intramedullary nailing between February 2001 and April 2013. Statistical analysis was performed utilizing multivariable logistic regression and Fisher exact tests.
RESULTS: The overall rate of VTE was twenty-four (7.1%) of the 336; thirteen (3.9%) were pulmonary embolism (PE), and eleven (3.3%), deep venous thrombosis (DVT). In two patients, adequate anticoagulation data were not available. We found no significant relationship between the type of anticoagulant used and VTE. There was a significant positive correlation found between lung-cancer histology and the development of VTE (p \u3c 0.001) or PE (p \u3c 0.001). The absence of radiation therapy approached significance (p = 0.06) with respect to decreased overall VTE risk. Wound complications were documented for 11 (3.3%) of the operations.
CONCLUSIONS: There is a high rate of VTE among those with skeletal metastatic disease who undergo intramedullary nailing, even while receiving postoperative thromboembolic prophylaxis. Current anticoagulation protocols may be inadequate. Wound-complication risk with anticoagulant use in this population is low and should not be a deterrent to adequate anticoagulant use for this population
Transverse force on a quantized vortex in a superconductor
The total transverse force acting on a quantized vortex in a type-II
superconductor determines the Hall response in the mixed state, yet a consensus
as to its correct form is still lacking. In this paper we present an
essentially exact expression for this force, valid in the superclean limit,
which was obtained by generalizing the recent work by Thouless, Ao, and Niu [D.
J. Thouless, P. Ao, and Q. Niu, Phys. Rev. Lett. 76, 3758 (1996)] on the Magnus
force in a neutral superfluid. We find the transverse force per unit length to
be , where is the sum of the
mass densities of the normal and superconducting components, is a vector
parallel to the line vortex with a magnitude equal to the quantized
circulation, and is the vortex velocity.Comment: 4 pages, Revtex, 1 figur
Percutaneous Liver Biopsy after Living Donor Liver Transplantation Resulting in Fulminant Hepatic Failure: The First Reported Case of Hepatic Compartment Syndrome
A 28-year-old female who underwent live donor liver transplantation 3 years prior presented after percutaneous liver biopsy with abdominal and shoulder pain, nausea, vomiting, and elevated liver enzymes. Computed tomography (CT) showed an intrahepatic and subcapsular hematoma. There was a progressive increase in liver enzymes, bilirubin, and INR and a decline in hemoglobin. Subsequent CT imaging revealed flattening of the portal vein consistent with compression by the enlarging hematoma. Liver failure ensued and the patient required urgent retransplantation. The explant demonstrated ischemic necrosis of greater than 90% of the liver parenchyma. We report this case of “Hepatic Compartment Syndrome” leading to fulminant hepatic failure
Constraining the WMAP9 bispectrum and trispectrum with needlets
We develop a needlet approach to estimate the amplitude of general (including
non-separable) bispectra and trispectra in the cosmic microwave background, and
apply this to the WMAP 9-year data. We obtain estimates for the `orthogonal'
bispectrum mode, yielding results which are consistent with the WMAP 7-year
data. We do not observe the frequency-dependence suggested by the WMAP team's
analysis of the 9-year data. We present 1- constraints on the `local'
trispectrum shape \gnl/10^5= -4.1\pm 2.3, the `' equilateral model
\gnl^{c_1}/10^6= -0.8\pm 2.9, and the constant model \gnl^{\rm{const}}/10^6=
-0.2\pm 1.8, together with a confidence-level upper bound on the
multifield local parameter \taunl<22000. We estimate the bias on these
parameters produced by point sources. The techniques developed in this paper
should prove useful for other datasets such as Planck.Comment: 21 pages - matches published versio
A phase 3, multi-center, multinational, randomized, double-blind, placebo-controlled study to evaluate the efficacy and safety of levofloxacin inhalation solution (APT-1026) in stable cystic fibrosis patients
Rationale
For patients with cystic fibrosis (CF), the use of inhaled antibiotics has become standard of care to suppress chronic Pseudomonas airways infection. There are limited antibiotic options formulated and approved for inhaled use and antibiotic efficacies attenuate over time, making additional inhaled antibiotic classes desirable. APT-1026 (levofloxacin inhalation solution, LIS) is a fluoroquinolone in development for management of chronic P. aeruginosa airways infection in patients with CF.
Objectives
To compare the safety and efficacy of a 28-day course of treatment with LIS 240 mg or placebo BID in persons ≥ 12 years old with CF and chronic P. aeruginosa infection.
Methods
A multinational, randomized (2:1), double-blinded study of LIS and placebo over 28 days in CF patients ≥ 12 years with chronic P. aeruginosa infection. Time to exacerbation was the primary endpoint. FEV1 (% predicted) and patient-reported quality of life were among secondary endpoints.
Main results
Baseline demographics for 330 subjects (LIS = 220) were similar although significantly more patients randomized to LIS had experienced multiple exacerbations in the year prior to study entry. There was no statistically significant difference in protocol-defined pulmonary exacerbations between treatment arms. Relative change in FEV1% predicted from baseline was significantly greater for patients randomized to LIS compared to those randomized to placebo (mean difference 1.31%, p = 0.01 [95% CI 0.27, 2.34%]). LIS was well-tolerated, with dysguesia the most frequent adverse event.
Conclusions
LIS did not demonstrate a difference in time to next exacerbation when compared to placebo. Reasons for this result are discussed but may be due to an imbalance in the frequency of prior pulmonary exacerbations between the two groups. An improvement in FEV1 (% predicted) at 28 days was observed and LIS was well tolerated. LIS is safe and has a potential role in the management of CF patients with chronic P. aeruginosa
AGN Feedback in Galaxy Groups: the Delicate Touch of Self-Regulated Outflows
AGN heating, through massive subrelativistic outflows, might be the key to
solve the long-lasting `cooling flow problem' in cosmological systems. In a
previous paper, we showed that cold accretion feedback and, to a lesser degree,
Bondi self-regulated models are in fact able to quench cooling rates for
several Gyr, at the same time preserving the mainc ool core features, like
observed density and temperature profiles. Is it true also for lighter systems,
such as galaxy groups? The answer is globally yes, although with remarkable
differences. Adopting a modified version of the AMR code FLASH 3.2, we found
that successful 3D simulations with cold and Bondi models are almost convergent
in the galaxy group environment, with mechanical efficiencies in the range
5.e-4 - 1.e-3 and 5.e-2 - 1.e-1, respectively. The evolutionary storyline of
galaxy groups is dominated by a quasi-continuous gentle injection with
sub-Eddington outflows (with mechanical power and velocity around 1.e44 erg/s
and 1.e4 km/s). The cold and hybrid accretion models present, in addition, very
short quiescence periods, followed by moderate outbursts (10 times the previous
phase), which generate a series of 10-20 kpc size cavities with high density
contrast, temperatures similar to the ambient medium and cold rims. After shock
heating, a phase of turbulence promotes gas mixing and diffusion of metals,
which peak along jet-axis (up to 40 kpc) during active phases. At this stage
the tunnel, produced by the enduring outflow (hard to detect in the mock SBx
maps), is easily fragmented, producing tiny buoyant bubbles, typically a few
kpc in size. In contrast to galaxy clusters, the AGN self-regulated feedback
has to be persistent, with a `delicate touch', rather than rare and explosive
strokes. This evolutionary difference dictates in the end that galaxy groups
are not scaled-down versions of clusters.Comment: Accepted by MNRAS; 22 pages, 7 figure
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