444 research outputs found
Reconstruction of the gastric passage by a side-to-side gastrogastrostomy after failed vertical-banded gastroplasty: a case report
INTRODUCTION: Vertical-banded gastroplasty, a technique that is commonly performed in the treatment of morbid obesity, represents a nonadjustable restrictive procedure which reduces the volume of the upper stomach by a vertical stapler line. In addition, a textile or silicone band restricts food passage through the stomach. CASE PRESENTATION: A 71-year-old woman presented with a severe gastric stenosis 11 years after vertical gastroplasty. We describe a side-to-side gastrogastrostomy as a safe surgical procedure to restore the physiological gastric passage after failed vertical-banded gastroplasty. CONCLUSION: Occasionally, restrictive procedures for morbid obesity cannot be converted into an alternative bariatric procedure to maintain weight control. This report demonstrates that a side-to-side gastrogastrostomy is a feasible and safe procedure
Failure of erythromycin to eliminate airway colonization with ureaplasma urealyticum in very low birth weight infants
BACKGROUND: Airway colonization of mechanically ventilated very low birth weight infants (birth weight < 1500 grams) by Ureaplasma urealyticum (Uu) is associated with an increased risk of bronchopulmonary dysplasia (BPD). While Uu is sensitive to erythromycin in vitro, the efficacy of intravenous (IV) erythromycin to eliminate Uu from the airways has not been studied. METHODS: 17 very low birth weight infants with Uu positive tracheal aspirate (TA) cultures were randomized to either 5 (8 infants) or 10 days (9 infants) of IV erythromycin lactobionate (40 mg/kg/day in 3 divided doses). Tracheal aspirate cultures for Uu were performed on days 0, 5, 10 and 15. RESULTS: Intravenous erythromycin failed to eliminate airway colonization in a large proportion of infants regardless of whether they received 5 or 10 days of treatment. Ureaplasma urealyticum was isolated from 4/15 (27%) of TAs obtained at 5 days, 5/12 TAs (42%) obtained at 10 days and 6/11(55%) TAs obtained at 15 days (combined group data). CONCLUSIONS: Erythromycin administered IV does not eliminate Uu from the airways in a large proportion of infants. Failure of erythromycin to eliminate Uu from the airways may contribute to the lack of efficacy of this drug in reducing the incidence of BPD in very low birth weight infants
A systematic variation of the stellar initial mass function in early-type galaxies
Much of our knowledge of galaxies comes from analysing the radiation emitted
by their stars. It depends on the stellar initial mass function (IMF)
describing the distribution of stellar masses when the population formed.
Consequently knowledge of the IMF is critical to virtually every aspect of
galaxy evolution. More than half a century after the first IMF determination,
no consensus has emerged on whether it is universal in different galaxies.
Previous studies indicated that the IMF and the dark matter fraction in galaxy
centres cannot be both universal, but they could not break the degeneracy
between the two effects. Only recently indications were found that massive
elliptical galaxies may not have the same IMF as our Milky Way. Here we report
unambiguous evidence for a strong systematic variation of the IMF in early-type
galaxies as a function of their stellar mass-to-light ratio, producing
differences up to a factor of three in mass. This was inferred from detailed
dynamical models of the two-dimensional stellar kinematics for the large
Atlas3D representative sample of nearby early-type galaxies spanning two orders
of magnitude in stellar mass. Our finding indicates that the IMF depends
intimately on a galaxy's formation history.Comment: 4 pages, 2 figures, LaTeX. Accepted for publication as a Nature
Letter. More information about our Atlas3D project is available at
http://purl.org/atlas3
Recommended from our members
DNA methylation-based biological age, genome-wide average DNA methylation, and conventional breast cancer risk factors.
DNA methylation-based biological age (DNAm age), as well as genome-wide average DNA methylation, have been reported to predict breast cancer risk. We aimed to investigate the associations between these DNA methylation-based risk factors and 18 conventional breast cancer risk factors for disease-free women. A sample of 479 individuals from the Australian Mammographic Density Twins and Sisters was used for discovery, a sample of 3354 individuals from the Melbourne Collaborative Cohort Study was used for replication, and meta-analyses pooling results from the two studies were conducted. DNAm age based on three epigenetic clocks (Hannum, Horvath and Levine) and genome-wide average DNA methylation were calculated using the HumanMethylation 450 K BeadChip assay data. The DNAm age measures were positively associated with body mass index (BMI), smoking, alcohol drinking and age at menarche (all nominal P < 0.05). Genome-wide average DNA methylation was negatively associated with smoking and number of live births, and positively associated with age at first live birth (all nominal P < 0.05). The association of DNAm age with BMI was also evident in within-twin-pair analyses that control for familial factors. This study suggests that some lifestyle and hormonal risk factors are associated with these DNA methylation-based breast cancer risk factors, and the observed associations are unlikely to be due to familial confounding but are likely causal. DNA methylation-based risk factors could interplay with conventional risk factors in modifying breast cancer risk
Deletion of L-Selectin Increases Atherosclerosis Development in ApoE−/− Mice
Atherosclerosis is an inflammatory disease characterized by accumulation of leukocytes in the arterial intima. Members of the selectin family of adhesion molecules are important mediators of leukocyte extravasation. However, it is unclear whether L-selectin (L-sel) is involved in the pathogenesis of atherosclerosis. In the present study, mice deficient in L-selectin (L-sel−/−) animals were crossed with mice lacking Apolipoprotein E (ApoE−/−). The development of atherosclerosis was analyzed in double-knockout ApoE/L-sel (ApoE−/− L-sel−/−) mice and the corresponding ApoE−/− controls fed either a normal or a high cholesterol diet (HCD). After 6 weeks of HCD, aortic lesions were increased two-fold in ApoE−/− L-sel−/− mice as compared to ApoE−/− controls (2.46%±0.54% vs 1.28%±0.24% of total aortic area; p<0.05). Formation of atherosclerotic lesions was also enhanced in 6-month-old ApoE−/− L-sel−/− animals fed a normal diet (10.45%±2.58% vs 1.87%±0.37%; p<0.05). In contrast, after 12 weeks of HCD, there was no difference in atheroma formation between ApoE−/− L-sel−/− and ApoE−/− mice. Serum cholesterol levels remained unchanged by L-sel deletion. Atherosclerotic plaques did not exhibit any differences in cellular composition assessed by immunohistochemistry for CD68, CD3, CD4, and CD8 in ApoE−/− L-sel−/− as compared to ApoE−/− mice. Leukocyte rolling on lesions in the aorta was similar in ApoE−/− L-sel−/− and ApoE−/− animals. ApoE−/− L-sel−/− mice exhibited reduced size and cellularity of peripheral lymph nodes, increased size of spleen, and increased number of peripheral lymphocytes as compared to ApoE−/− controls. These data indicate that L-sel does not promote atherosclerotic lesion formation and suggest that it rather protects from early atherosclerosis
Wave Equation Numerical Resolution: a Comprehensive Mechanized Proof of a C Program
We formally prove correct a C program that implements a numerical scheme for
the resolution of the one-dimensional acoustic wave equation. Such an
implementation introduces errors at several levels: the numerical scheme
introduces method errors, and floating-point computations lead to round-off
errors. We annotate this C program to specify both method error and round-off
error. We use Frama-C to generate theorems that guarantee the soundness of the
code. We discharge these theorems using SMT solvers, Gappa, and Coq. This
involves a large Coq development to prove the adequacy of the C program to the
numerical scheme and to bound errors. To our knowledge, this is the first time
such a numerical analysis program is fully machine-checked.Comment: No. RR-7826 (2011
Uniform electron gases
We show that the traditional concept of the uniform electron gas (UEG) --- a
homogeneous system of finite density, consisting of an infinite number of
electrons in an infinite volume --- is inadequate to model the UEGs that arise
in finite systems. We argue that, in general, a UEG is characterized by at
least two parameters, \textit{viz.} the usual one-electron density parameter
and a new two-electron parameter . We outline a systematic
strategy to determine a new density functional across the
spectrum of possible and values.Comment: 8 pages, 2 figures, 5 table
Bone mineral density measurement and osteoporosis treatment after a fragility fracture in older adults: regional variation and determinants of use in Quebec
BACKGROUND: Osteoporosis (OP) is a skeletal disorder characterized by reduced bone strength and predisposition to increased risk of fracture, with consequent increased risk of morbidity and mortality. It is therefore an important public health problem. International and Canadian associations have issued clinical guidelines for the diagnosis and treatment of OP. In this study, we identified potential predictors of bone mineral density (BMD) testing and OP treatment, which include place of residence. METHODS: Our study was a retrospective population-based cohort study using data from the Quebec Health Insurance Board. The studied population consisted of all individuals 65 years and older for whom a physician claimed a consultation for a low velocity vertebral, hip, wrist, or humerus fracture in 1999 and 2000. Individuals were considered to have undergone BMD testing if there was a claim for such a procedure within two years following a fracture. They were considered to have received an OP treatment if there was at least one claim to Quebec's health insurance plan (RAMQ) for OP treatment within one year following a fracture. We performed descriptive analyses and logistic regressions by gender. Predictors included age, site of fracture, social status, comorbidity index, prior BMD testing, prior OP treatment, long-term glucocorticoid use, and physical distance to BMD device. RESULTS: The cohort, 77% of which was female, consisted of 25,852 individuals with fragility fractures. BMD testing and OP treatment rates were low and gender dependent (BMD: men 4.6%; women 13.1%; OP treatment: men 9.9%; women 29.7%). There was an obvious regional variation, particularly in BMD testing, ranging from 0 to 16%. Logistic regressions demonstrate that individuals living in long term care facilities received less BMD testing. Patients who had suffered from vertebral fractures, or who had received prior OP treatment or BMD testing, regardless of gender, subsequently received more BMD testing and OP treatments. Furthermore, increasing the distance between a patient's residence and BMD facility precluded likelihood of BMD testing. CONCLUSION: BMD testing rate was extremely low but not completely explained by reduced physical access; gender, age, social status, prior BMD testing and OP treatment were all important predictors for future BMD testing and OP treatment
Functional imaging studies of cognition using 99mTc-HMPAO SPECT: empirical validation using the n-back working memory paradigm
{Purpose} Functional activation protocols are widely applied for the study of brain-cognition relations. Only few take advantage of the intrinsic characteristics of SPECT, particularly those allowing cognitive assessment outside of the camera, in settings close to the standard clinical or laboratory ones. The purpose of the study was to assess the feasibility of a split-dose activation protocol with 99mTc-HMPAO using low irradiation dose. {Materials and methods} A two-scans protocol was applied to 12 healthy young volunteers using 270 MBq of 99mTc-HMPAO per scan, with each image associated to a particular experimental condition of the verbal {n}-back working memory task (0-back, 2-back). Subtraction method was used to identify regional brain activity related to the task. {Results} Voxel-wise statistical analysis showed left lateralized activity associated with the 2-back task, compared to the 0-back task. Activated regions, mainly prefrontal and parietal, were similar to those observed in previous fMRI and 15O-PET studies. {Conclusion} The results support the use of 99mTc-HMPAO SPECT for the investigation of brain-cognition relations and demonstrate the feasibility of optimal quality images despite low radiopharmaceutical doses. The findings also acknowledge the use of HMPAO as a radioligand to capture neuro-energetic modulations linked to cognitive activity. They encourage extending the application of the described activation protocol to clinical populations
New genetic loci implicated in fasting glucose homeostasis and their impact on type 2 diabetes risk.
Levels of circulating glucose are tightly regulated. To identify new loci influencing glycemic traits, we performed meta-analyses of 21 genome-wide association studies informative for fasting glucose, fasting insulin and indices of beta-cell function (HOMA-B) and insulin resistance (HOMA-IR) in up to 46,186 nondiabetic participants. Follow-up of 25 loci in up to 76,558 additional subjects identified 16 loci associated with fasting glucose and HOMA-B and two loci associated with fasting insulin and HOMA-IR. These include nine loci newly associated with fasting glucose (in or near ADCY5, MADD, ADRA2A, CRY2, FADS1, GLIS3, SLC2A2, PROX1 and C2CD4B) and one influencing fasting insulin and HOMA-IR (near IGF1). We also demonstrated association of ADCY5, PROX1, GCK, GCKR and DGKB-TMEM195 with type 2 diabetes. Within these loci, likely biological candidate genes influence signal transduction, cell proliferation, development, glucose-sensing and circadian regulation. Our results demonstrate that genetic studies of glycemic traits can identify type 2 diabetes risk loci, as well as loci containing gene variants that are associated with a modest elevation in glucose levels but are not associated with overt diabetes
- …