587 research outputs found
Demographic characteristics of patients with extrapulmonary tuberculosis in Germany
The aim of the present study was to determine the demographics of patients with extrapulmonary tuberculosis in Germany. Data on 26,302 tuberculosis cases from a national survey carried out during the period 1996-2000 were analysed. The crude proportion of tuberculosis patients with extrapulmonary manifestations was 21.6%. Extrapulmonary tuberculosis was most likely among females, children aged <15 yrs and persons originating from Africa and Asia. Females tended to be more likely to have any form of extrapulmonary tuberculosis than males, except pleural tuberculosis. The strength of this association was strongest in the age range 25-64 yrs and less pronounced amongst the oldest patients. Children were particularly prone to the development of lymphatic and meningeal tuberculosis, whereas the likelihood of genitourinary tuberculosis increased with increasing age. Asian and African patients were generally more likely than persons from other areas to have lymphatic, osteoarticular, meningeal and miliary tuberculosis. The analysis shows important differences, by age, sex and origin, in the likelihood of a tuberculosis patient presenting with extrapulmonary tuberculosis. Since the relative contribution of the foreign-born to tuberculosis in low-prevalence countries is rising, extrapulmonary tuberculosis must be taken into account more often in the differential diagnostic work-up of these patients, particularly among those originating from Asia and Africa
Enhanced collectivity in 74Ni
The neutron-rich nucleus 74Ni was studied with inverse-kinematics inelastic
proton scattering using a 74Ni radioactive beam incident on a liquid hydrogen
targetat a center-of-mass energy of 80 MeV. From the measured de-excitation
gamma-rays, the population of the first 2+ state was quantified. The
angle-integrated excitation cross section was determined to be 14(4) mb. A
deformation length of delta = 1.04(16) fm was extracted in comparison with
distorted wave theory, which suggests that the enhancement of collectivity
established for 70Ni continues up to 74Ni. A comparison with results of shell
model and quasi-particle random phase approximation calculations indicates that
the magic character of Z = 28 or N = 50 is weakened in 74Ni
Measurement of excited states in 40Si and evidence for weakening of the N=28 shell gap
Excited states in 40Si have been established by detecting gamma-rays
coincident with inelastic scattering and nucleon removal reactions on a liquid
hydrogen target. The low excitation energy, 986(5) keV, of the 2+[1] state
provides evidence of a weakening in the N=28 shell closure in a neutron-rich
nucleus devoid of deformation-driving proton collectivity.Comment: accepted for publication in PR
Comparing methods for estimating patient‐specific treatment effects in individual patient data meta‐analysis
Meta-analysis of individual patient data (IPD) is increasingly used to synthesize data from multiple trials. IPD meta-analysis offers several advantages over
meta-analyzing aggregate data, including the capacity to individualize treatment
recommendations. Trials usually collect information on many patient characteristics. Some of these covariates may strongly interact with treatment (and thus
be associated with treatment effect modification) while others may have little
effect. It is currently unclear whether a systematic approach to the selection of
treatment-covariate interactions in an IPD meta-analysis can lead to better estimates of patient-specific treatment effects. We aimed to answer this question
by comparing in simulations the standard approach to IPD meta-analysis (no
variable selection, all treatment-covariate interactions included in the model)
with six alternative methods: stepwise regression, and five regression methods that perform shrinkage on treatment-covariate interactions, that is, least
absolute shrinkage and selection operator (LASSO), ridge, adaptive LASSO,
Bayesian LASSO, and stochastic search variable selection. Exploring a range
of scenarios, we found that shrinkage methods performed well for both continuous and dichotomous outcomes, for a variety of settings. In most scenarios, these methods gave lower mean squared error of the patient-specific
treatment effect as compared with the standard approach and stepwise regression. We illustrate the application of these methods in two datasets from
cardiology and psychiatry. We recommend that future IPD meta-analysis that
aim to estimate patient-specific treatment effects using multiple effect modifiers should use shrinkage methods, whereas stepwise regression should be
avoided
A prospective observational study comparing a non-operator dependent automatic PWV analyser to pulse pressure, in assessing arterial stiffness in hemodialysis.
BACKGROUND: Chronic kidney disease (CKD) accelerates vascular stiffening related to age. Arterial stiffness may be evaluated measuring the carotid-femoral pulse wave velocity (PWV) or more simply, as recommended by KDOQI, monitoring pulse pressure (PP). Both correlate to survival and incidence of cardiovascular disease. PWV can also be estimated on the brachial artery using a Mobil-O-Graph; a non-operator dependent automatic device. The aim was to analyse whether, in a dialysis population, PWV obtained by Mobil-O-Graph (MogPWV) is more sensitive for vascular aging than PP.
METHODS: A cohort of 143 patients from 4 dialysis units has been followed measuring MogPWV and PP every 3 to 6 months and compared to a control group with the same risk factors but an eGFR > 30 ml/min.
RESULTS: MogPWV contrarily to PP did discriminate the dialysis population from the control group. The mean difference translated in age between the two populations was 8.4 years. The increase in MogPWV, as a function of age, was more rapid in the dialysis group. 13.3% of the dialysis patients but only 3.0% of the control group were outliers for MogPWV. The mortality rate (16 out of 143) was similar in outliers and inliers (7.4 and 8.0%/year). Stratifying patients according to MogPWV, a significant difference in survival was seen. A high parathormone (PTH) and to be dialysed for a hypertensive nephropathy were associated to a higher baseline MogPWV.
CONCLUSIONS: Assessing PWV on the brachial artery using a Mobil-O-Graph is a valid and simple alternative, which, in the dialysis population, is more sensitive for vascular aging than PP. As demonstrated in previous studies PWV correlates to mortality. Among specific CKD risk factors only PTH is associated with a higher baseline PWV.
TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02327962
Two-neutron knockout from neutron-deficient Ar, S, and Si
Two-neutron knockout reactions from nuclei in the proximity of the proton
dripline have been studied using intermediate-energy beams of neutron-deficient
Ar, S, and Si. The inclusive cross sections, and also the
partial cross sections for the population of individual bound final states of
the Ar, S and Si knockout residues, have been determined
using the combination of particle and -ray spectroscopy. Similar to the
two-proton knockout mechanism on the neutron-rich side of the nuclear chart,
these two-neutron removal reactions from already neutron-deficient nuclei are
also shown to be consistent with a direct reaction mechanism.Comment: Phys. Rev. C, rapid communication, in pres
An Innovative Non-Linear Prediction Model for Clinical Benefit in Women with Newly Diagnosed Breast Cancer Using Baseline FDG-PET/CT and Clinical Data
Objectives: We aimed to develop a novel non-linear statistical model integrating primary tumor features on baseline [18F]-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT), molecular subtype, and clinical data for treatment benefit prediction in women with newly diagnosed breast cancer using innovative statistical techniques, as opposed to conventional methodological approaches. Methods: In this single-center retrospective study, we conducted a comprehensive assessment of women newly diagnosed with breast cancer who had undergone a FDG-PET/CT scan for staging prior to treatment. Primary tumor (PT) volume, maximum and mean standardized uptake value (SUVmax and SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured on PET/CT. Clinical data including clinical staging (TNM) but also PT anatomical site, histology, receptor status, proliferation index, and molecular subtype were obtained from the medical records. Overall survival (OS), progression-free survival (PFS), and clinical benefit (CB) were assessed as endpoints. A logistic generalized additive model was chosen as the statistical approach to assess the impact of all listed variables on CB. Results: 70 women with newly diagnosed breast cancer (mean age 63.3 ± 15.4 years) were included. The most common location of breast cancer was the upper outer quadrant (40.0%) in the left breast (52.9%). An invasive ductal adenocarcinoma (88.6%) with a high tumor proliferation index (mean ki-67 expression 35.1 ± 24.5%) and molecular subtype B (51.4%) was by far the most detected breast tumor. Most PTs displayed on hybrid imaging a greater volume (12.8 ± 30.4 cm3) with hypermetabolism (mean ± SD of PT maximum SUVmax, SUVmean, MTV, and TLG, respectively: 8.1 ± 7.2, 4.9 ± 4.4, 12.7 ± 30.4, and 47.4 ± 80.2). Higher PT volume (p < 0.01), SUVmax (p = 0.04), SUVmean (p = 0.03), and MTV (<0.01) significantly compromised CB. A considerable majority of patients survived throughout this period (92.8%), while five women died (7.2%). In fact, the OS was 31.7 ± 14.2 months and PFS was 30.2 ± 14.1 months. A multivariate prediction model for CB with excellent accuracy could be developed using age, body mass index (BMI), T, M, PT TLG, and PT volume as predictive parameters. PT volume and PT TLG demonstrated a significant influence on CB in lower ranges; however, beyond a specific cutoff value (respectively, 29.52 cm3 for PT volume and 161.95 cm3 for PT TLG), their impact on CB only reached negligible levels. Ultimately, the absence of distant metastasis M displayed a strong positive impact on CB far ahead of the tumor size T (standardized average estimate 0.88 vs. 0.4). Conclusions: Our results emphasized the pivotal role played by FDG-PET/CT prior to treatment in forecasting treatment outcomes in women newly diagnosed with breast cancer. Nevertheless, careful consideration is required when selecting the methodological approach, as our innovative statistical techniques unveiled non-linear influences of predictive biomarkers on treatment benefit, highlighting also the importance of early breast cancer diagnosis.Peer Reviewe
Evolution of the energy spacing in odd-mass K, Cl and P isotopes for
The energy of the first excited state in the neutron-rich N=28 nucleus 45Cl
has been established via in-beam gamma-ray spectroscopy following proton
removal. This energy value completes the systematics of the
E(1/2^+_1)-E(3/2^+_1) level spacing in odd-mass K, Cl and P isotopes for
N=20-28. The results are discussed in the framework of shell-model calculations
in the sd-fp model space. The contribution of the central, spin-orbit and
tensor components is discussed from a calculation based on a proton single-hole
spectrum from G-matrix and pi + rho meson exchange potentials. A composite
model for the proton 0d_{3/2}-1s_{1/2} single-particle energy shift is
presented.Comment: Phys. Rev. C, in pres
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