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1.
Optica ; 11(4): 569-576, 2024 Apr 20.
Article in English | MEDLINE | ID: mdl-39006164

ABSTRACT

With histopathology results typically taking several days, the ability to stage tumors during interventions could provide a step change in various cancer interventions. X-ray technology has advanced significantly in recent years with the introduction of phase-based imaging methods. These have been adapted for use in standard labs rather than specialized facilities such as synchrotrons, and approaches that enable fast 3D scans with conventional x-ray sources have been developed. This opens the possibility to produce 3D images with enhanced soft tissue contrast at a level of detail comparable to histopathology, in times sufficiently short to be compatible with use during surgical interventions. In this paper we discuss the application of one such approach to human esophagi obtained from esophagectomy interventions. We demonstrate that the image quality is sufficiently high to enable tumor T staging based on the x-ray datasets alone. Alongside detection of involved margins with potentially life-saving implications, staging tumors intra-operatively has the potential to change patient pathways, facilitating optimization of therapeutic interventions during the procedure itself. Besides a prospective intra-operative use, the availability of high-quality 3D images of entire esophageal tumors can support histopathological characterization, from enabling "right slice first time" approaches to understanding the histopathology in the full 3D context of the surrounding tumor environment.

2.
Opt Express ; 32(4): 4839-4856, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38439226

ABSTRACT

A laboratory X-ray imaging system with a setup that closely resembles commercial micro-CT systems with a fixed source-to-detector distance of ∼90 cm is investigated for single distance propagation-based phase-contrast imaging and computed tomography (CT). The system had a constant source-to-detector distance, and the sample positions were optimized. Initially, a PTFE wire was imaged, both in 2D and 3D, to characterize fringe contrast and spatial resolution for different X-ray source settings and source-to-sample distances. The results were compared to calculated values based on theoretical models and to simulated (wave-optics based) results, with good agreement being found. The optimization of the imaging system is discussed. CT scans of two biological samples, a tissue-engineered esophageal scaffold and a rat heart, were then acquired at the optimum parameters, demonstrating that significant image quality improvements can be obtained with widely available components placed inside fixed-length cabinets through proper optimization of propagation-based phase-contrast.

3.
J Phys D Appl Phys ; 56(45): 45LT02, 2023 Nov 09.
Article in English | MEDLINE | ID: mdl-37601626

ABSTRACT

X-ray phase contrast imaging (XPCI) methods give access to contrast mechanisms that are based on the refractive properties of matter on top of the absorption coefficient in conventional x-ray imaging. Ultra small angle x-ray scattering (USAXS) is a phase contrast mechanism that arises due to multiple refraction events caused by physical features of a scale below the physical resolution of the used imaging system. USAXS contrast can therefore give insight into subresolution structural information, which is an ongoing research topic in the vast field of different XPCI techniques. In this study, we quantitatively compare the USAXS signal retrieved by the beam tracking XPCI technique with the gold standard of the analyzer based imaging XPCI technique using a synchrotron x-ray source. We find that, provided certain conditions are met, the two methods measure the same quantity.

4.
Sci Rep ; 13(1): 8707, 2023 May 29.
Article in English | MEDLINE | ID: mdl-37248325

ABSTRACT

Beam tracking X-ray Phase Contrast Imaging is a "Shack-Hartmann" type approach which uses a pre-sample mask to split the x-rays into "beamlets" which are interrogated by a detector with sufficient resolution. The ultimate spatial resolution is determined by the size of the mask apertures, however achieving this resolution level requires "stepping" the sample or the mask in increments equal to the aperture size ("dithering"). If an array of circular apertures is used (which also provides two-dimensional phase sensitivity) instead of long parallel slits, this stepping needs to be carried out in two directions, which lengthens scan times significantly. We present a mask design obtained by offsetting rows of circular apertures, allowing for two-dimensional sensitivity and isotropic resolution while requiring sample or mask stepping in one direction only. We present images of custom-built phantoms and biological specimens, demonstrating that quantitative phase retrieval and near aperture-limited spatial resolutions are obtained in two orthogonal directions.

5.
Sci Rep ; 12(1): 21336, 2022 12 09.
Article in English | MEDLINE | ID: mdl-36494470

ABSTRACT

We present a flyscan compatible acquisition scheme for three-modal X-Ray Computed Tomography (CT) with two-dimensional phase sensitivity. Our approach is demonstrated using a "beam tracking" setup, through which a sample's attenuation, phase (refraction) and scattering properties can be measured from a single frame, providing three complementary contrast channels. Up to now, such setups required the sample to be stepped at each rotation angle to sample signals at an adequate rate, to prevent resolution losses, anisotropic resolution, and under-sampling artefacts. However, the need for stepping necessitated a step-and-shoot implementation, which is affected by motors' overheads and increases the total scan time. By contrast, our proposed scheme, by which continuous horizontal and vertical translations of the sample are integrated with its rotation (leading to a "cycloidal-spiral" trajectory), is fully compatible with continuous scanning (flyscans). This leads to greatly reduced scan times while largely preserving image quality and isotropic resolution.


Subject(s)
Algorithms , Tomography, X-Ray Computed , X-Rays , Tomography, X-Ray Computed/methods , Artifacts , Phantoms, Imaging
6.
Sci Rep ; 12(1): 20185, 2022 11 23.
Article in English | MEDLINE | ID: mdl-36418420

ABSTRACT

Super-resolution fluorescence microscopy can be achieved by image reconstruction after spatially patterned illumination or sequential photo-switching and read-out. Reconstruction algorithms and microscope performance are typically tested using simulated image data, due to a lack of strategies to pattern complex fluorescent patterns with nanoscale dimension control. Here, we report direct electron-beam patterning of fluorescence nanopatterns as calibration standards for super-resolution fluorescence. Patterned regions are identified with both electron microscopy and fluorescence labelling of choice, allowing precise correlation of predefined pattern dimensions, a posteriori obtained electron images, and reconstructed super-resolution images.


Subject(s)
Electrons , Lighting , Calibration , Microscopy, Fluorescence , Algorithms
7.
Front Psychol ; 13: 946626, 2022.
Article in English | MEDLINE | ID: mdl-36059769

ABSTRACT

Here we present a systematic plan to the experimental study of test-retest reliability in the multitasking domain, adopting the multitrait-multimethod (MTMM) approach to evaluate the psychometric properties of performance in Düker-type speeded multiple-act mental arithmetic. These form of tasks capacitate the experimental analysis of integrated multi-step processing by combining multiple mental operations in flexible ways in the service of the overarching goal of completing the task. A particular focus was on scoring methodology, particularly measures of response speed variability. To this end, we present data of two experiments with regard to (a) test-retest reliability, (b) between-measures correlational structure, (c) and stability (test-retest practice effects). Finally, we compared participants with high versus low performance variability to assess ability-related differences in measurement precision (typically used as proxy to "simulate" patient populations), which is especially relevant in the applied fields of clinical neuropsychology. The participants performed two classic integrated multi-act arithmetic tasks, combining addition and verification (Exp. 1) and addition and comparison (Exp. 2). The results revealed excellent test-retest reliability for the standard and the variability measures. The analysis of between-measures correlational structure revealed the typical pattern of convergent and discriminant relationships, and also, that absolute response speed variability was highly correlated with average speed (r > 0.85), indicating that these measures mainly deliver redundant information. In contrast, speed-adjusted (relativized) variability revealed discriminant validity being correlated to a much lesser degree with average speed, indicating that this measure delivers additional information not already provided by the speed measure. Furthermore, speed-adjusted variability was virtually unaffected by test-retest practice, which makes this measure interesting in situations with repeated testing.

8.
Sci Rep ; 12(1): 3354, 2022 03 01.
Article in English | MEDLINE | ID: mdl-35233022

ABSTRACT

Multi-modal X-ray imaging allows the extraction of phase and dark-field (or "Ultra-small Angle Scatter") images alongside conventional attenuation ones. Recently, scan-based systems using conventional sources that can simultaneously output the above three images on relatively large-size objects have been developed by various groups. One limitation is the need for some degree of spatial coherence, achieved either through the use of microfocal sources, or by placing an absorption grating in front of an extended source. Both these solutions limit the amount of flux available for imaging, with the latter also leading to a more complex setup with additional alignment requirements. Edge-illumination partly overcomes this as it was proven to work with focal spots of up to 100 micron. While high-flux, 100 micron focal spot sources do exist, their comparatively large footprint and high cost can be obstacles to widespread translation. A simple solution consists in placing a single slit in front of a large focal spot source. We used a tunable slit to study the system performance at various effective focal spot sizes, by extracting transmission, phase and dark-field images of the same specimens for a range of slit widths. We show that consistent, repeatable results are obtained for varying X-ray statistics and effective focal spot sizes. As the slit width is increased, the expected reduction in the raw differential phase peaks is observed, compensated for in the retrieval process by a broadened sensitivity function. This leads to the same values being correctly retrieved, but with a slightly larger error bar i.e. a reduction in phase sensitivity. Concurrently, a slight increase in the dark-field signal is also observed.


Subject(s)
Lighting , Microscopy, Phase-Contrast , Radiography , X-Rays
9.
Micromachines (Basel) ; 12(1)2020 Dec 24.
Article in English | MEDLINE | ID: mdl-33374159

ABSTRACT

High resolution dense lines patterned by focused electron beam-induced deposition (FEBID) have been demonstrated to be promising for lithography. One of the challenges is the presence of interconnecting material, which is often carbonaceous, between the lines as a result of the Gaussian line profile. We demonstrate the use of focused electron beam-induced etching (FEBIE) as a scanning electron microscope (SEM)-based direct-write technique for the removal of this interconnecting material, which can be implemented without removing the sample from the SEM for post processing. Secondary electron (SE) imaging has been used to monitor the FEBIE process, and atomic force microscopy (AFM) measurements confirm the fabrication of well separated FEBID lines. We further demonstrate the application of this technique for removing interconnecting material in high resolution dense lines using backscattered electron (BSE) imaging to monitor the process.

10.
Behav Brain Res ; 379: 112366, 2020 02 03.
Article in English | MEDLINE | ID: mdl-31743728

ABSTRACT

Research has demonstrated that stress can exacerbate AD pathology in transgenic mouse models of AD. The purpose of the present studies was to extend this work by determining whether a social stressor, isolation stress, would increase the number of Aß plaques in 5xFAD + transgenic mice in comparison to group-housed controls, and accelerate the onset of cognitive deficits in contextual fear-conditioning. Additionally, we aimed to determine whether the pathological impact of isolation stress could be prevented through exposure to exercise alone or to exercise and an enriched environment throughout the isolation period. Two-month-old 5xFAD + and 5xFAD- animals were isolated or group-housed for two and three months. An additional subset of 5xFAD + mice were housed in isolation, housed in isolation with an exercise wheel, or housed in isolation with an exercise wheel and an enriched environment. Both two and three months of isolation stress significantly increased the number of plaques in the hippocampus of 5xFAD + mice, and three months of isolation increased hippocampal BACE1 expression. Isolated animals also displayed a significant cognitive deficit in contextual fear-conditioning, independent of genotype. Furthermore, neither exercise nor an enriched environment were able to prevent these isolation-induced effects. Understanding how stress impacts the onset and progression of AD is critical, as many individuals endure significant stress over their lifespan, including prolonged social isolation, a societal trend likely to worsen with time.


Subject(s)
Alzheimer Disease , Amyloid Precursor Protein Secretases/metabolism , Aspartic Acid Endopeptidases/metabolism , Cognitive Dysfunction , Hippocampus/metabolism , Physical Conditioning, Animal/physiology , Plaque, Amyloid/metabolism , Social Isolation , Stress, Psychological , Alzheimer Disease/etiology , Alzheimer Disease/metabolism , Alzheimer Disease/prevention & control , Amyloid beta-Peptides/metabolism , Animals , Cognitive Dysfunction/etiology , Cognitive Dysfunction/metabolism , Cognitive Dysfunction/prevention & control , Disease Models, Animal , Environment , Housing, Animal , Male , Mice , Mice, Transgenic , Running/physiology , Stress, Psychological/complications , Stress, Psychological/metabolism , Stress, Psychological/prevention & control
11.
Hum Reprod ; 34(8): 1514-1522, 2019 08 01.
Article in English | MEDLINE | ID: mdl-31348498

ABSTRACT

STUDY QUESTION: How is timing of voice break related to other male pubertal milestones as well as to BMI? SUMMARY ANSWER: We provide a comprehensive temporal analysis of male pubertal milestones, including reproductive hormone dynamics, confirm voice break as a late milestone of male puberty and report a likely causal relationship between higher BMI and earlier age at voice break in men. WHAT IS KNOWN ALREADY: Voice break represents a late pubertal milestone and recalled age at voice break is frequently used in epidemiological studies as a measure of puberty. In contrast, clinical studies use mainly testicular enlargement and/or genital tanner stage as the marker of pubertal onset. However, neither correlation of pubertal milestones nor reproductive hormone dynamics have been assessed in detail previously. Further, although BMI and puberty timing are known to be closely linked, cause and effect between these traits are not known. STUDY DESIGN, SIZE, DURATION: The study included a population-based mixed cross-sectional and longitudinal cohort (2006-2014, COPENHAGEN Puberty Study) of 730 healthy Danish boys. Data for 55 871 male research participants from the 23andMe study were obtained, including genome-wide single nucleotide polymorphism data and age at voice break. PARTICIPANTS/MATERIALS, SETTING, METHODS: We performed a detailed evaluation of pubertal milestones and reproductive hormone levels (study population 1). A Mendelian randomization (MR) approach was used to determine the likely causal link between BMI and timing of voice break (study population 2). MAIN RESULTS AND THE ROLE OF CHANCE: Voice break occurred at mean age 13.6 (95% CI: 13.5-13.8) years. At voice break, mean (95% CI) testosterone levels, LH levels and bi-testicular volume were 10.9 (10.0-11.7) nmol/L, 2.4 (2.2-2.5) IU/L and 24 (23-25) mL, respectively. Voice break correlated moderately strongly with timing of male pubertal milestones, including testicular enlargement, gonadarche, pubarche, sweat odor, axillary hair growth and testosterone above limit of detection (r2 range: 0.43-0.61). Timing of all milestones was negatively associated with age-specific BMI (all P ≤ 0.001). MR analyses inferred likely causal effects of higher BMI on earlier voice break in males (-0.35 years/approximate SD, P < 0.001). LIMITATIONS, REASONS FOR CAUTION: Participation rate of the population-based cohort was 25%. Further, boys that were followed longitudinally were examined approximately every 6 months limiting the time resolution of pubertal milestones. Using adult BMI as exposure instead of prepubertal BMI in the MR analysis and the known inaccuracies of the testosterone immunoassay at low testosterone levels may be further limitations. WIDER IMPLICATIONS OF THE FINDINGS: We provide valuable normative data on the temporal relation of male pubertal milestones. Further, the likely causal relationship between BMI and puberty timing highlights the importance of preventing obesity in childhood. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by Danish Agency for Science, Technology and Innovation (09-067 180); Danish Ministry of the Environment, CeHoS (MST-621-00 065); Capital Region of Denmark (R129-A3966); Ministry of Higher Education and Science (DFF-1331-00 113); Innovation Fund Denmark (InnovationsFonden, 14-2013-4); The International Center for Research and Research Training in Endocrine Disrupting Effects of Male Reproduction and Child Health. B.H., F.R.D., J.R.B.P. and K.K.O. are supported by the Medical Research Council (MC_UU_12015/2). The 23andMe study is supported by the National Human Genome Research Institute of the National Institutes of Health (R44HG006981). Members of the 23andMe Research Team are employees of 23andMe, Inc. and hold stock or stock options in 23andMe. TRIAL REGISTRATION NUMBER: NCT01411527.


Subject(s)
Body Mass Index , Pediatric Obesity/physiopathology , Puberty/physiology , Testosterone/blood , Voice , Adolescent , Age Factors , Child , Denmark , Humans , Longitudinal Studies , Male , Young Adult
12.
Psychol Assess ; 30(3): 339-357, 2018 03.
Article in English | MEDLINE | ID: mdl-28406669

ABSTRACT

We provide a psychometric analysis of commonly used performance indices of the d2 sustained-attention test, and give methodical guidelines and recommendations, based on this research. We examined experimental effects of repeated testing on performance speed and accuracy (omission and commission errors), and further evaluated aspects of test reliability by means of cumulative reliability function (CRF) analysis. These aspects were also examined for a number of alternative (yet commonly used) scoring techniques and valuation methods. Results indicate that performance is sensitive to change, both differentially within (time-on-task) and between (test-retest) sessions. These effects did not severely affect test reliability, since perfect score reliability was observed for measures of speed (and was even preserved with half the test length) while variability and error scores were more problematic with respect to reliability. Notably, limitations particularly hold for commission but less so for omission errors. Our recommendations to researchers and practitioners are that (a) only the speed score (and error-corrected speed score) is eligible for highly reliable assessment, that (b) error scores might be used as a secondary measure (e.g., to check for aberrant behavior), that (c) variability scores might not be used at all. Given the exceptional reliability of performance speed, and (d) test length may be reduced up to 50%, if necessary for time-economic reasons, to serve purposes of population screening and field assessment. (PsycINFO Database Record


Subject(s)
Attention , Psychological Tests , Adult , Female , Humans , Male , Practice Guidelines as Topic , Psychometrics , Reproducibility of Results , Research Design
13.
Gesundheitswesen ; 80(7): 598-605, 2018 Jul.
Article in German | MEDLINE | ID: mdl-27975338

ABSTRACT

OBJECTIVE: To determine mental health service utilization before and after consultation of a psychiatric liaison service ("Support 25") among youths aged 16-24 years suffering from mental disorders and receiving unemployment benefits. METHODS: Longitudinal registration of mental health service use over a 9-month period (N=148); measurement of possible moderators with questionnaires and rating scales. RESULTS: Mental health service utilization increased from initially 22% to 40% and 47.5% 3 and 6 months after receiving individual treatment recommendation. Low-threshold psychosocial counseling was frequented more often than specific psychiatric or psychotherapeutic treatment. Subjects who contacted mental health services showed a trend towards a lower level of psychosocial functioning than subjects who did not seek treatment. Stigma-related factors did not hinder mental health service use. CONCLUSIONS: Despite a high degree of psychiatric morbidity, the surveyed sample of unemployed youths had problems to successfully enter mental health services. Although a substantial increase in service use was observed after receiving psychoeducational information at a psychiatric liaison service, the use of low-threshold counseling predominated. This finding suggests that the mental health system should adapt better to the specific needs of young unemployed, for example, by expanding low-threshold psychiatric pre-treatment offers at vocational centers.


Subject(s)
Counseling , Mental Disorders , Mental Health Services , Unemployment , Adolescent , Adult , Germany , Humans , Referral and Consultation , Young Adult
14.
Nanotechnology ; 28(47): 474002, 2017 Nov 24.
Article in English | MEDLINE | ID: mdl-29027905

ABSTRACT

Nanostructures of platinum-carbon nanocomposite material have been formed by electron-beam induced deposition. These consist of nanodots and nanowires with a minimum size ∼20 nm, integrated within ∼100 nm nanogap n-type silicon-on-insulator transistor structures. The nanodot transistors use ∼20 nm Pt/C nanodots, tunnel-coupled to Pt/C nanowire electrodes, bridging the Si nanogaps. Room-temperature single-electron transistor operation has been measured, and single-electron current oscillations and 'Coulomb diamonds' observed. In nanowire transistors, the temperature dependence from 290 to 8 K suggests that the current is a combination of thermally activated and tunnelling transport of carriers across potential barriers along the current path, and that the Pt/C is p-type at low temperature.

15.
Scand J Med Sci Sports ; 25 Suppl 4: 126-34, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26589126

ABSTRACT

During evolution, mitochondrial DNA haplogroups of arctic populations may have been selected for lower coupling of mitochondrial respiration to ATP production in favor of higher heat production. We show that mitochondrial coupling in skeletal muscle of traditional and westernized Inuit habituating northern Greenland is identical to Danes of western Europe haplogroups. Biochemical coupling efficiency was preserved across variations in diet, muscle fiber type, and uncoupling protein-3 content. Mitochondrial phenotype displayed plasticity in relation to lifestyle and environment. Untrained Inuit and Danes had identical capacities to oxidize fat substrate in arm muscle, which increased in Danes during the 42 days of acclimation to exercise, approaching the higher level of the Inuit hunters. A common pattern emerges of mitochondrial acclimatization and evolutionary adaptation in humans at high latitude and high altitude where economy of locomotion may be optimized by preservation of biochemical coupling efficiency at modest mitochondrial density, when submaximum performance is uncoupled from VO2max and maximum capacities of oxidative phosphorylation.


Subject(s)
Deltoid Muscle/metabolism , Inuit , Mitochondria, Muscle/metabolism , Oxidative Phosphorylation , Quadriceps Muscle/metabolism , White People , Adenosine Triphosphate/biosynthesis , Adult , Cell Respiration , Cold Temperature , DNA, Mitochondrial , Deltoid Muscle/cytology , Denmark/ethnology , Fatty Acids/metabolism , Female , Greenland/ethnology , Haplotypes , Humans , Inuit/genetics , Ion Channels/metabolism , Male , Mitochondrial Proteins/metabolism , Oxidation-Reduction , Oxygen Consumption , Quadriceps Muscle/cytology , Seasons , Skiing/physiology , Thermogenesis , Uncoupling Protein 3 , White People/genetics
16.
Handchir Mikrochir Plast Chir ; 47(3): 155-63, 2015 Jun.
Article in German | MEDLINE | ID: mdl-26084854

ABSTRACT

UNLABELLED: Background/Goal: An arthroscopically assisted management of intra-articular distal radius fractures may improve the quality of reduction. Furthermore, concomitant ligament and triangular fibrocartilage complex injuries can be identified and treated. However, this approach increases the duration of surgery. If severe soft tissue lesions, such as SL-ligament disruptions are treated simultaneously, a longer post-operative immobilisation will be required. The aim of this study was to measure the clinical outcome one year after arthroscopically assisted treatment of intra-articular distal radius fractures. PATIENTS AND METHODS: In a retrospective study from 2011 to 2013 we identified 27 patients with intra-articular distal radius fractures who were treated with volar fixed angle plates in an arthroscopically assisted fashion. The amount of associated injuries, the duration of surgery and the time of immobilisation were documented. One year postoperatively we evaluated 23 of these patients using several scores. Patient satisfaction, range of motion, visual analogue scale and grip strength were assessed using a standardised questionnaire. RESULTS: The mean surgery time was 111 min (60-190 min). On average, we found 1.4 (0-3) associated injuries per patient. Seventy percent (19) of all patients had a triangular fibrocartilage complex lesion, 67% (16) had some degree of scapholunate ligament lesion. The mean number of interventions in addition to the plate fixation was 1.1 per patient (0-3). Among these were debridements of the triangular fibrocartilage complex in 11 cases (41%) and scapholunate ligament repairs in 4 cases (15%). The mean immobilisation time was 22 (0-42) days. At one year after surgery, the mean Mayo wrist score was 79 (65-95) and the DASH score was 12 (0-49). CONCLUSION: The arthroscopically assisted management of intra-articular distal radius fractures helps to identify and treat associated injuries. However, it results in extended surgery and immobilisation time, especially if concomitant intra-articular lesions are treated. In our group of patients, the clinical outcome after one year was nonetheless very good.


Subject(s)
Arthroscopy/methods , Intra-Articular Fractures/surgery , Radius Fractures/surgery , Wrist Injuries/surgery , Adult , Aged , Aged, 80 and over , Algorithms , Female , Follow-Up Studies , Fracture Healing/physiology , Humans , Ligaments, Articular/injuries , Ligaments, Articular/surgery , Male , Middle Aged , Postoperative Care , Retrospective Studies , Treatment Outcome , Triangular Fibrocartilage/injuries , Triangular Fibrocartilage/surgery
17.
Handchir Mikrochir Plast Chir ; 47(3): 175-81, 2015 Jun.
Article in German | MEDLINE | ID: mdl-26084857

ABSTRACT

AIM: Therapy of scapholunate advanced collapse (SLAC) wrist should be guided by the degree of arthritic changes within the radioscaphoid and midcarpal joints (stage 1-3 after Watson). Diagnostic investigations usually include X-ray imaging and wrist arthoscopy. In the present study, the interrater reliability of SLAC wrist stage classification by means of X-ray image analysis was evaluated between radiologists and hand surgeons. Ultimately, the influence of diagnostic wrist arthroscopy on the final stage classification was determined. PATIENTS AND METHODS: Retrospectively, 38 SLAC wrists of 37 patients were included in this study. Conventional X-ray images in a dorso-palmar and lateral view were performed before diagnostic wrist arthroscopy. The degree of carpal collapse on X-rays was determined by 2 radiologists and 2 surgeons (1 board certified hand surgeon, 1 plastic surgeon, both experienced in hand surgery since years). After 14 days the stages were re-evaluated by the surgeons with the digital images from the wrist arthroscopies at hand. RESULTS: While the interrater reliability turned out to be 'weak' amidst the radiologists, it was classified as 'light' among the surgeons. We found a 'weak' and a 'light' interrater reliability between the surgeons and the radiologists. Radiologists tended to assess the degree of severity higher than surgeons. The additional knowledge of the digital arthroscopy images led to a different classification in 55%. When X-rays were assessed in combination with the arthroscopy findings, both stage 1 and stage 3 were diagnosed less frequently. CONCLUSIONS: Our study suggests that interpreting X-ray films alone is an unreliable method to assess the stage of SLAC wrist. We believe that additional diagnostic measures such as wrist arthroscopy are needed to accurately diagnose the SLAC wrist stage.


Subject(s)
Arthroscopy , Disability Evaluation , Joint Dislocations/classification , Joint Dislocations/diagnosis , Ligaments, Articular/injuries , Lunate Bone/injuries , Osteoarthritis/classification , Osteoarthritis/diagnosis , Scaphoid Bone/injuries , Adult , Aged , Cooperative Behavior , Female , Humans , Interdisciplinary Communication , Lunate Bone/surgery , Male , Middle Aged , Observer Variation , Retrospective Studies , Rupture , Scaphoid Bone/surgery
18.
HIV Med ; 16(7): 403-11, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25974723

ABSTRACT

OBJECTIVES: Lipid-based nutrient supplements (LNSs) are increasingly used in HIV programmes in resource-limited settings. However, the possible effects of LNSs on the plasma concentrations of antiretroviral drugs have not been assessed. Here, we aimed to assess the effects of LNSs on plasma efavirenz and nevirapine trough concentrations in Ethiopian adult HIV-infected patients. METHODS: The effects of LNSs were studied in adults initiating antiretroviral therapy (ART) in a randomized trial. Patients with body mass index (BMI) > 17 kg/m(2) (n = 282) received daily supplementation of an LNS containing whey (LNS/w), an LNS containing soy (LNS/s) or no LNS. Trough plasma concentrations of efavirenz and nevirapine were measured at 1 and 2 months. Genotyping for 516 G>T and 983 T>C polymorphisms of the cytochrome P450 (CYP) 2B6 locus was performed. Multilevel linear mixed-effects models were used to assess the associations between LNS and plasma efavirenz and nevirapine concentrations. RESULTS: In patients with BMI > 17 kg/m(2), nevirapine concentrations were lower in the LNS/w and LNS/s groups by a median of -2.3 µg/mL [interquartile range (IQR) -3.9; -0.9 µg/mL; P = 0.002] and -2.1 µg/mL (IQR -3.9; -0.9 µg/mL; P = 0.01), respectively, compared with the group not receiving supplements. There were no differences between groups with respect to efavirenz plasma concentrations. The CYP2B6 516 G>T polymorphism was associated with a 5 µg/mL higher plasma efavirenz concentration compared with the wild type (P < 0.0001), while it was not associated with plasma nevirapine concentrations. CONCLUSIONS: Intake of an LNS was associated with lower plasma nevirapine trough concentrations, indicating possible drug-LNS interactions. The clinical relevance of such reductions in nevirapine exposure is not clear. Plasma efavirenz concentration was not affected by the LNS.


Subject(s)
Benzoxazines/therapeutic use , Black People , Fatty Acids, Essential/administration & dosage , HIV Infections/drug therapy , Nevirapine/blood , Reverse Transcriptase Inhibitors/blood , Adult , Alkynes , Antiretroviral Therapy, Highly Active , Benzoxazines/blood , Cyclopropanes , Cytochrome P-450 CYP2B6/blood , Dietary Supplements , Ethiopia/epidemiology , Female , HIV Infections/blood , Humans , Lipids/administration & dosage , Lipids/blood , Male , Micronutrients/administration & dosage , Nevirapine/therapeutic use , Reverse Transcriptase Inhibitors/therapeutic use , Urban Population
19.
AJNR Am J Neuroradiol ; 36(3): 594-9, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25614474

ABSTRACT

BACKGROUND AND PURPOSE: The Patient Reported Outcomes Measurement Information System is a newly developed outcomes measure promulgated by the National Institutes of Health. This study compares changes in pain and physical function-related measures of this system with changes on the Numeric Rating Pain Scale, Roland Morris Disability Index, and the European Quality of Life scale 5D questionnaire in patients undergoing transformational epidural steroid injections for radicular pain. MATERIALS AND METHODS: One hundred ninety-nine patients undergoing transforaminal epidural steroid injections for radicular pain were enrolled in the study. Before the procedure, they rated the intensity of their pain by using the 0-10 Numeric Rating Pain Scale, Roland Morris Disability Index, and European Quality of Life scale 5D questionnaire. Patients completed the Patient Reported Outcomes Measurement Information System Physical Function, Pain Behavior, and Pain Interference short forms before transforaminal epidural steroid injections and at 3 and 6 months. Seventy and 43 subjects replied at 3- and 6-month follow-up. Spearman rank correlations were used to assess the correlation between the instruments. The minimally important differences were calculated for each measurement tool as an indicator of meaningful change. RESULTS: All instruments were responsive in detecting changes at 3- and 6-month follow-up (P < .0001). There was significant correlation between changes in Patient Reported Outcomes Measurement Information System scores and legacy questionnaires from baseline to 3 months (P < .05). There were, however, no significant correlations in changes from 3 to 6 months with any of the instruments. CONCLUSIONS: The studied Patient Reported Outcomes Measurement Information System domains offered responsive and correlative psychometric properties compared with legacy instruments in a population of patients undergoing transforaminal epidural steroid injections for radicular pain.


Subject(s)
Patient Outcome Assessment , Radiculopathy/drug therapy , Adult , Aged , Disability Evaluation , Female , Humans , Injections, Epidural/methods , Male , Middle Aged , Pain Measurement , Psychometrics , Quality of Life , Self Care , Treatment Outcome , United States
20.
Rev Sci Instrum ; 85(11): 11E117, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25430296

ABSTRACT

Photons in the MeV range emitted from the dense plasma focus (DPF) at the NSTec North Las Vegas Facility have been measured with both neutron-damaged GaAs and natural diamond photoconductive detectors (PCDs). The DPF creates or "pinches" plasmas of various gases (e.g., H2, D2, Ne, Ar., etc.) that have enough energy to create MeV photons from either bremsstrahlung and/or (n,n(')) reactions if D2 gas is used. The high bandwidth of the PCDs enabled the first ever measurement of the fast micro-pinches present in DPF plasmas. Comparisons between a slower more conventional scintillator/photomultiplier tube based nuclear physics detectors were made to validate the response of the PCDs to fast intense MeV photon signals. Significant discrepancies in the diamond PCD responses were evident.

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