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Laparoscopic Adjustable Gastric Banding and Hypoglycemia
Obesity is commonplace, and surgical treatment usually includes Roux-en-Y gastric bypasses (RYGBs). RYGBs have the most documented side effects including vitamin deficiencies, rebound weight gain, and symptomatic hypoglycemia; fewer series exist describing hypoglycemia following other bariatric operations. We reviewed all patients undergoing laparoscopic adjustable gastric banding (LAGB) at our institution between 2008 and 2012. Three patients were identified to have symptomatic hypoglycemia following LAGB. Mean time from surgery was 33 months (range 14–45 months), and mean weight loss was 32.7 kg (range 15.9–43.1 kg). None of the patients had preexisting diabetes. Therefore, symptomatic hypoglycemia should be investigated irrespective of bariatric operation
A Modern Cohort of Duodenal Obstruction Patients: Predictors of Delayed Transition to Full Enteral Nutrition
Background:. A common site for neonatal intestinal obstruction is the duodenum. Delayed establishment of enteral nutritional autonomy continues to challenge surgeons and, since early institution of nutritional support is critical in postoperative newborns, identification of patients likely to require alternative nutritional support may improve their outcomes. Therefore, we aimed to investigate risk factors leading to delayed establishment of full enteral nutrition in these patients. Methods:. 87 patients who were surgically treated for intrinsic duodenal obstructions from 1998 to 2012 were reviewed. Variables were tested as potential risk factors. Median time to full enteral nutrition was estimated using the Kaplan-Meier method. Independent risk factors of delayed transition were identified using the multivariate Cox proportional hazards regression model. Results:. Median time to transition to full enteral nutrition was 12 days (interquartile range: 9–17 days). Multivariate Cox analysis identified three significant risk factors for delayed enteral nutrition: gestational age (GA) ≤ 35 weeks (P < .001), congenital heart disease (CHD) (P = .02), and malrotation (P = .03). Conclusions:. CHD and Prematurity are most commonly associated with delayed transition to full enteral nutrition. Thus, in these patients, supportive nutrition should strongly be considered pending enteral nutritional autonomy
Creating a low-dimensional quantum gas using dark states in an inelastic evanescent-wave mirror
We discuss an experimental scheme to create a low-dimensional gas of
ultracold atoms, based on inelastic bouncing on an evanescent-wave mirror.
Close to the turning point of the mirror, the atoms are transferred into an
optical dipole trap. This scheme can compress the phase-space density and can
ultimately yield an optically-driven atom laser. An important issue is the
suppression of photon scattering due to ``cross-talk'' between the mirror
potential and the trapping potential. We propose that for alkali atoms the
photon scattering rate can be suppressed by several orders of magnitude if the
atoms are decoupled from the evanescent-wave light. We discuss how such dark
states can be achieved by making use of circularly-polarized evanescent waves.Comment: 8 pages, 4 figure
Neural correlates of enhanced visual short-term memory for angry faces: An fMRI study
Copyright: © 2008 Jackson et al.Background: Fluid and effective social communication requires that both face identity and emotional expression information are encoded and maintained in visual short-term memory (VSTM) to enable a coherent, ongoing picture of the world and its players. This appears to be of particular evolutionary importance when confronted with potentially threatening displays of emotion - previous research has shown better VSTM for angry versus happy or neutral face identities.Methodology/Principal Findings: Using functional magnetic resonance imaging, here we investigated the neural correlates of this angry face benefit in VSTM. Participants were shown between one and four to-be-remembered angry, happy, or neutral faces, and after a short retention delay they stated whether a single probe face had been present or not in the previous display. All faces in any one display expressed the same emotion, and the task required memory for face identity. We find enhanced VSTM for angry face identities and describe the right hemisphere brain network underpinning this effect, which involves the globus pallidus, superior temporal sulcus, and frontal lobe. Increased activity in the globus pallidus was significantly correlated with the angry benefit in VSTM. Areas modulated by emotion were distinct from those modulated by memory load.Conclusions/Significance: Our results provide evidence for a key role of the basal ganglia as an interface between emotion and cognition, supported by a frontal, temporal, and occipital network.The authors were supported by a Wellcome Trust grant (grant number 077185/Z/05/Z) and by BBSRC (UK) grant BBS/B/16178
Arp 220: A Post-starburst Galaxy with Little Current Star Formation outside of Its Nuclear Disks
The ultraluminous infrared galaxy Arp 220 is a late-stage merger with several tidal structures in the outskirts and two very compact, dusty nuclei that show evidence for extreme star formation and host at least one active galactic nucleus (AGN). New and archival high-resolution images taken by the Hubble Space Telescope provide a state-of-the-art view of the structures, dust, and stellar clusters in Arp 220. These images cover the near-ultraviolet, optical, and near-infrared in both broad- and narrowband filters. We find that ∼90% of the H α emission arises from a shock-ionized bubble emanating from the AGN in the western nucleus, while the nuclear disks dominate the Pa β emission. Four very young (∼3–6 Myr) but lower-mass (≲10 ^4 M _⊙ ) clusters are detected in H α within a few arcseconds of the nuclei, but they produce less than 1% of the line emission. We see little evidence for a population of massive clusters younger than 100 Myr anywhere in Arp 220, unlike previous reports in the literature. From the masses and ages of the detected clusters, we find that star formation took place more or less continuously starting approximately a few gigayears ago with a moderate rate between ≈3 and 12 M _⊙ yr ^−1 . Approximately 100 Myr ago, star formation shut off suddenly everywhere (possibly due to a merging event), except in the nuclear disks. A very recent flicker of weak star formation produced the four young, low-mass clusters, while the rest of the galaxy appears to have remained in a post-starburst state. Cluster ages indicate that the tidal structures on the west side of the galaxy are older than those on the east side, but all appear to predate the shutoff of star formation. Arp 220 has many of the characteristics expected of a “shocked post-starburst galaxy,” since most of the system has been in a post-starburst state for the past ∼100 Myr and the detected H α emission arises from shocked rather than photoionized gas
Comparison of CT and integrated PET-CT based radiation therapy planning in patients with malignant pleural mesothelioma
<p>Abstract</p> <p>Background</p> <p>When combined with adequate tumoricidal doses, accurate target volume delineation remains to be the one of the most important predictive factors for radiotherapy (RT) success in locally advanced or medically inoperable malignant pleural mesothelioma (MPM) patients. Recently, 18-fluorodeoxyglucose positron emission tomography (PET) has demonstrated significant improvements in diagnosis and accurate staging of MPM. However, role of additional PET data has not been studied in RT planning (RTP) of patients with inoperable MPM or in those who refuse surgery. Therefore, we planned to compare CT with co-registered PET-CT as the basis for delineating target volumes in these patients group.</p> <p>Methods</p> <p>Retrospectively, the CT and co-registered PET-CT data of 13 patients with histologically proven MPM were utilized to delineate target volumes separately. For each patient, target volumes (gross tumor volume [GTV], clinical target volume [CTV], and planning target volume [PTV]) were defined using the CT and PET-CT fusion data sets. The PTV was measured in two ways: PTV1 was CTV plus a 1-cm margin, and PTV2 was GTV plus a 1-cm margin. We analyzed differences in target volumes.</p> <p>Results</p> <p>In 12 of 13 patients, compared to CT-based delineation, PET-CT-based delineation resulted in a statistically significant decrease in the mean GTV, CTV, PTV1, and PTV2. In these 12 patients, mean GTV decreased by 47.1% ± 28.4%, mean CTV decreased by 38.7% ± 24.7%, mean PTV1 decreased by 31.1% ± 23.1%, and mean PTV2 decreased by 40.0% ± 24.0%. In 4 of 13 patients, hilar lymph nodes were identified by PET-CT that was not identified by CT alone, changing the nodal status of tumor staging in those patients.</p> <p>Conclusion</p> <p>This study demonstrated the usefulness of PET-CT-based target volume delineation in patients with MPM. Co-registration of PET and CT information reduces the likelihood of geographic misses, and additionally, significant reductions observed in target volumes may potentially allow escalation of RT dose beyond conventional limits potential clinical benefits in tumor control rates, which needs to be tested in future studies.</p
An unbiased ranking of murine dietary models based on their proximity to human metabolic dysfunction-associated steatotic liver disease (MASLD)
Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease, encompasses steatosis and metabolic dysfunction-associated steatohepatitis (MASH), leading to cirrhosis and hepatocellular carcinoma. Preclinical MASLD research is mainly performed in rodents; however, the model that best recapitulates human disease is yet to be defined. We conducted a wide-ranging retrospective review (metabolic phenotype, liver histopathology, transcriptome benchmarked against humans) of murine models (mostly male) and ranked them using an unbiased MASLD ‘human proximity score’ to define their metabolic relevance and ability to induce MASH-fibrosis. Here, we show that Western diets align closely with human MASH; high cholesterol content, extended study duration and/or genetic manipulation of disease-promoting pathways are required to intensify liver damage and accelerate significant (F2+) fibrosis development. Choline-deficient models rapidly induce MASH-fibrosis while showing relatively poor translatability. Our ranking of commonly used MASLD models, based on their proximity to human MASLD, helps with the selection of appropriate in vivo models to accelerate preclinical research
Isolation and Characterization of Intestinal Epithelial Cells from Normal and SIV-Infected Rhesus Macaques
Impairment of intestinal epithelial barriers contributes to the progression of HIV/SIV infection and leads to generalized HIV-induced immune-cell activation during chronic infection. Rhesus macaques are the major animal model for studying HIV pathogenesis. However, detailed characterization of isolated rhesus epithelial cells (ECs) from intestinal tissues is not well defined. It is also not well documented whether isolated ECs had any other cell contaminants from intestinal tissues during the time of processing that might hamper interpretation of EC preparations or cultures. In this study, we identify and characterize ECs based on flow cytometry and immunohistochemistry methods using various enzymatic and mechanical isolation techniques to enrich ECs from intestinal tissues. This study shows that normal healthy ECs differentially express HLA-DR, CD23, CD27, CD90, CD95 and IL-10R markers. Early apoptosis and upregulation of ICAM-1 and HLA-DR in intestinal ECs are thought to be the key features in SIV mediated enteropathy. The data suggest that intestinal ECs might be playing an important role in mucosal immune responses by regulating the expression of different important regulatory and adhesion molecules and their function
A systematic review of the psychometric properties of self-report research utilization measures used in healthcare
<p>Abstract</p> <p>Background</p> <p>In healthcare, a gap exists between what is known from research and what is practiced. Understanding this gap depends upon our ability to robustly measure research utilization.</p> <p>Objectives</p> <p>The objectives of this systematic review were: to identify self-report measures of research utilization used in healthcare, and to assess the psychometric properties (acceptability, reliability, and validity) of these measures.</p> <p>Methods</p> <p>We conducted a systematic review of literature reporting use or development of self-report research utilization measures. Our search included: multiple databases, ancestry searches, and a hand search. Acceptability was assessed by examining time to complete the measure and missing data rates. Our approach to reliability and validity assessment followed that outlined in the <it>Standards for Educational and Psychological Testing</it>.</p> <p>Results</p> <p>Of 42,770 titles screened, 97 original studies (108 articles) were included in this review. The 97 studies reported on the use or development of 60 unique self-report research utilization measures. Seven of the measures were assessed in more than one study. Study samples consisted of healthcare providers (92 studies) and healthcare decision makers (5 studies). No studies reported data on acceptability of the measures. Reliability was reported in 32 (33%) of the studies, representing 13 of the 60 measures. Internal consistency (Cronbach's Alpha) reliability was reported in 31 studies; values exceeded 0.70 in 29 studies. Test-retest reliability was reported in 3 studies with Pearson's <it>r </it>coefficients > 0.80. No validity information was reported for 12 of the 60 measures. The remaining 48 measures were classified into a three-level validity hierarchy according to the number of validity sources reported in 50% or more of the studies using the measure. Level one measures (n = 6) reported evidence from any three (out of four possible) <it>Standards </it>validity sources (which, in the case of single item measures, was all applicable validity sources). Level two measures (n = 16) had evidence from any two validity sources, and level three measures (n = 26) from only one validity source.</p> <p>Conclusions</p> <p>This review reveals significant underdevelopment in the measurement of research utilization. Substantial methodological advances with respect to construct clarity, use of research utilization and related theory, use of measurement theory, and psychometric assessment are required. Also needed are improved reporting practices and the adoption of a more contemporary view of validity (<it>i.e.</it>, the <it>Standards</it>) in future research utilization measurement studies.</p
Star clusters near and far; tracing star formation across cosmic time
© 2020 Springer-Verlag. The final publication is available at Springer via https://doi.org/10.1007/s11214-020-00690-x.Star clusters are fundamental units of stellar feedback and unique tracers of their host galactic properties. In this review, we will first focus on their constituents, i.e.\ detailed insight into their stellar populations and their surrounding ionised, warm, neutral, and molecular gas. We, then, move beyond the Local Group to review star cluster populations at various evolutionary stages, and in diverse galactic environmental conditions accessible in the local Universe. At high redshift, where conditions for cluster formation and evolution are more extreme, we are only able to observe the integrated light of a handful of objects that we believe will become globular clusters. We therefore discuss how numerical and analytical methods, informed by the observed properties of cluster populations in the local Universe, are used to develop sophisticated simulations potentially capable of disentangling the genetic map of galaxy formation and assembly that is carried by globular cluster populations.Peer reviewedFinal Accepted Versio
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