1,721 research outputs found
Laparoscopic surgery for Crohn’s disease: a meta-analysis of perioperative complications and long term outcomes compared with open surgery
BACKGROUND: Previous meta-analyses have had conflicting conclusions regarding the differences between laparoscopic and open techniques in patients with Crohn’s Disease. The objective of this meta-analysis was to compare outcomes in patients with Crohn’s disease undergoing laparoscopic or open surgical resection. METHODS: A literature search of EMBASE, MEDLINE, The Cochrane Central Register of Controlled Trials and the US National Institute of Health’s Clinical Trials Registry was completed. Randomized clinical trials and non-randomized comparative studies were included if laparoscopic and open surgical resections were compared. Primary outcomes assessed included perioperative complications, recurrence requiring surgery, small bowel obstruction and incisional hernia. RESULTS: 34 studies were included in the analysis, and represented 2,519 patients. Pooled analysis showed reduced perioperative complications in patients undergoing laparoscopic resection vs. open resection (Risk Ratio 0.71, 95% CI 0.58 – 0.86, P = 0.001). There was no evidence of a difference in the rate of surgical recurrence (Rate Ratio 0.78, 95% CI 0.54 – 1.11, P = 0.17) or small bowel obstruction (Rate Ratio 0.63, 95% CI 0.28 – 1.45, P = 0.28) between techniques. There was evidence of a decrease in incisional hernia following laparoscopic surgery (Rate Ratio 0.24, 95% CI 0.07 – 0.82, P = 0.02). CONCLUSIONS: This is the largest review in this topic. The results of this analysis are based primarily on non-randomized studies and thus have significant limitations in regards to selection bias, confounding, lack of blinding and potential publication bias. Although we found evidence of decreased perioperative complications and incisional hernia in the laparoscopic group, further randomized controlled trials, with adequate follow up, are needed before strong recommendations can be made
A Herschel study of Planetary Nebulae
We present Herschel PACS and SPIRE images of the dust shells around the
planetary nebulae NGC 650, NGC 6853, and NGC 6720, as well as images showing
the dust temperature in their shells. The latter shows a rich structure, which
indicates that internal extinction in the UV is important despite the highly
evolved status of the nebulae.Comment: 2 pages, 1 figure, 2012, proceedings IAU Symposium 283 Planetary
Nebulae: An Eye to the Futur
Impostorism and anxiety contribute to burnout among resident physicians
Purpose: Physician burnout is an issue that has come to the forefront in the past decade. While many factors contribute to burnout the impact of impostorism and self-doubt has largely been ignored. We investigated the relationship of anxiety and impostorism to burnout in postgraduate medical learners. Materials and methods: Postgraduate learners in four diverse training programs: Family Medicine (FM), Paediatric Medicine (PM), Anesthesiology (AN), and General Surgery (GS) were surveyed to identify the incidence of impostorism (IP), anxiety, and burnout. IP, anxiety, and burnout were evaluated using the Clance Impostor Phenomenon Scale (CIPS), Maslach Burnout Inventory-Human Services Survey (MBI-HSS), and the General Anxiety Disorder-7 (GAD-7) questionnaires, respectively. Burnout was defined as meeting burnout criteria on all three domains. Relationships between IP, anxiety, and burnout were explored. Results: Two hundred and sixty-nine residents responded to the survey (response rate 18.8%). Respondents were distributed evenly between specialties (FM = 24.9%, PM = 33.1%, AN = 20.4%, GS = 21.6%). IP was identified in 62.7% of all participants. The average score on the CIPS was 66.4 (SD = 14.4), corresponding to ‘frequent feelings of impostorism.’ Female learners were at higher risk for IP (RR = 1.27, 95% CI: 1.03–1.57). Burnout, as defined by meeting burnout criteria on all three subscales, was detected in 23.3% of respondents. Significant differences were seen in burnout between specialties (p = 0.02). GS residents were more likely to experience burnout (31.7%) than PM and AN residents (26.7 and 10.0%, respectively, p = 0.02). IP was an independent risk factor for both anxiety (RR = 3.64, 95% CI:1.96–6.76) and burnout (RR = 1.82, 95% CI: 1.07–3.08). Conclusions: Impostorism is commonly experienced by resident learners independent of specialty and contributes to learner anxiety and burnout. Supervisors and Program Directors must be aware of the prevalence of IP and the impact on burnout. Initiatives to mitigate IP may improve resident learner wellness and decrease burnout in postgraduate learners
Analysis of the correlation dimension for inertial particles
We obtain an implicit equation for the correlation dimension which describes cluster- ing of inertial particles in a complex flow onto a fractal measure. Our general equation involves a propagator of a nonlinear stochastic process in which the velocity gradient of the fluid appears as additive noise. When the long-time limit of the propagator is considered our equation reduces to an existing large-deviation formalism from which it is difficult to extract concrete results. In the short-time limit, however, our equation reduces to a solvability condition on a partial differential equation. In the case where the inertial particles are much denser than the fluid, we show how this approach leads to a perturbative expansion of the correlation dimension, for which the coefficients can be obtained exactly and in principle to any order. We derive the perturbation series for the correlation dimension of inertial particles suspended in three-dimensional spatially smooth random flows with white-noise time correlations, obtaining the first 33 non-zero coefficients exactly
A Phase II Trial of the Epothilone B Analog Ixabepilone (BMS-247550) in Patients with Metastatic Melanoma
Ixabepilone (BMS-247550), an epothilone B analog, is a microtubule stabilizing agent which has shown activity in several different tumor types and preclinical models in melanoma. In an open label, one-arm, multi-center phase II trial the efficacy and toxicity of this epothilone was investigated in two different cohorts: chemotherapy-naïve (previously untreated) and previously treated patients with metastatic melanoma.Eligible patients had histologically-confirmed stage IV melanoma, with an ECOG performance status of 0 to 2. Ixabepilone was administered at a dose of 20 mg/m(2) on days 1, 8, and 15 during each 28-day cycle. The primary endpoint was response rate (RR); secondary endpoints were time to progression (TTP) and toxicity. Twenty-four patients were enrolled and 23 were evaluable for response. Initial serum lactate dehydrogenase (LDH) levels were elevated in 6/11 (55%) of the previously treated and in 5/13 (38%) of the previously untreated patients. No complete or partial responses were seen in either cohort. One patient in the previously treated group developed neutropenia and fatal septic shock. Seventeen patients (8 in the previously untreated group and 9 in the previously treated group) progressed after 2 cycles, whereas six patients (3 in each group) had stable disease after 2-6 cycles. Median TTP was 1.74 months in the previously untreated group (95% CI = 1.51 months, upper limit not estimated) and 1.54 months in the previously treated group (95% CI = 1.15 months, 2.72 months). Grade 3 and/or 4 toxicities occurred in 5/11 (45%) of previously untreated and in 5/13 (38%) of previously treated patients and included neutropenia, peripheral neuropathy, fatigue, diarrhea, and dyspnea.Ixabepilone has no meaningful activity in either chemotherapy-naïve (previously untreated) or previously treated patients with metastatic melanoma. Further investigation with ixabepilone as single agent in the treatment of melanoma is not warranted.Clinical Trials.gov NCT00036764
Intragenic Meiotic Crossovers Generate Novel Alleles with Transgressive Expression Levels
Meiotic recombination is an evolutionary force that generates new genetic diversity upon which selection can act. Whereas multiple studies have assessed genome-wide patterns of recombination and specific cases of intragenic recombination, few studies have assessed intragenic recombination genome-wide in higher eukaryotes. We identified recombination events within or near genes in a population of maize recombinant inbred lines (RILs) using RNA-sequencing data. Our results are consistent with case studies that have shown that intragenic crossovers cluster at the 5\u27 ends of some genes. Further, we identified cases of intragenic crossovers that generate transgressive transcript accumulation patterns, that is, recombinant alleles displayed higher or lower levels of expression than did nonrecombinant alleles in any of ~100 RILs, implicating intragenic recombination in the generation of new variants upon which selection can act. Thousands of apparent gene conversion events were identified, allowing us to estimate the genome-wide rate of gene conversion at SNP sites (4.9 X 10-5). The density of syntenic genes (i.e., those conserved at the same genomic locations since the divergence of maize and sorghum) exhibits a substantial correlation with crossover frequency, whereas the density of nonsyntenic genes (i.e., those which have transposed or been lost subsequent to the divergence of maize and sorghum) shows little correlation, suggesting that crossovers occur at higher rates in syntenic genes than in nonsyntenic genes. Increased rates of crossovers in syntenic genes could be either a consequence of the evolutionary conservation of synteny or a biological process that helps to maintain synteny
Remnant gas in evolved circumstellar disks: Herschel PACS observations of 10-100 Myr old disk systems
We present Herschel PACS spectroscopy of the [OI] 63 micron gas-line for
three circumstellar disk systems showing signs of significant disk evolution
and/or planet formation: HR 8799, HD 377 and RX J1852.3-3700. [OI] is
undetected toward HR 8799 and HD 377 with 3 sigma upper limits of 6.8 x 10^-18
W m^-2 and 9.9 x 10^-18 W m^-2 respectively. We find an [OI] detection for RX
J1852.3-3700 at 12.3 +- 1.8 x 10^-18 W m^-2. We use thermo-chemical disk models
to model the gas emission, using constraints on the [OI] 63 micron, and
ancillary data to derive gas mass upper limits and constrain gas-to-dust
ratios. For HD 377 and HR 8799, we find 3 sigma upper limits on the gas mass of
0.1-20 Mearth. For RX J1852.3-3700, we find two distinct disk scenarios that
could explain the detection of [OI] 63 micron and CO(2-1) upper limits reported
from the literature: (i) a large disk with gas co-located with the dust (16-500
AU), resulting in a large tenuous disk with ~16 Mearth of gas, or (ii) an
optically thick gas disk, truncated at ~70 AU, with a gas mass of 150 Mearth.
We discuss the implications of these results for the formation and evolution of
planets in these three systems.Comment: Accepted for publication in ApJ, 8 pages ApJ style (incl.
references), 2 figures, 4 table
Methods and Compositions Based on Culturing Microorganisms in Low Sedimental Fluid Shear Conditions
The benefits of applying a low sedimental fluid shear environment to manipulate microorganisms were examined. Microorganisms obtained from a low sedimental fluid shear culture, which exhibit modified phenotypic and molecular genetic characteristics, are useful for the development of novel and improved diagnostics, therapeutics, vaccines, and bio-industrial products. Furthermore, application of low sedimental fluid conditions to microorganisms permits identification of molecules uniquely expressed under these conditions, providing a basis for the design of new therapeutic targets
Association of atypical femoral fractures with bisphosphonate use by patients with varus hip geometry
- …