Search

Objective: To estimate the incidence, prevalence, and correlates of atrial fibrillation (AF) in a global population with rheumatic heart disease (RHD). Methods: Bibliographic databases were searched to identify all published studies providing data on AF in patients with RHD. Random-effects meta-analysis method was used to pool estimates. Results: Eighty-three studies were included, reporting data from 75,637 participants with RHD in 42 countries. The global prevalence of AF in RHD was 32.8% (range: 4.3%–79.9%). It was higher in severe valvular disease (30.8% vs 20.7%, p = 0.009), in severe mitral valve disease compared to severe aortic disease (30.4% vs 6.3%, p = 0.038). The global cumulative incidence of AF in patients with RHD was 4.8%, 11.4%, 13.2%, and 30.8% at 1, 2, 5, and 10 years of follow-up, respectively. From comparison between patients with and without AF, AF was associated with increased age (mean difference [MD]: 9.5 years; 95% CI: 7.8–1.3), advanced heart failure (odds ratio [OR]: 4.4; 95% CI 2.1–9.3), tricuspid valve involvement (OR: 4.0; 95% CI: 3.0–5.3), history of thromboembolism (OR: 6.2; 95% CI: 3.4–11.4), highly sensitive C-reactive protein (MD: 5.5 mg/dL; 95% CI: 1.2–9.8), systolic pulmonary arterial pressure (MD: 3.6 mmHg; 95% CI: 0.8–6.3), right atrium pressure (MD: 1.5 mmHg; 95% CI: 1.0–2.0), and left atrium diameter (MD: 8.1 mm; 95% CI: 5.5–10.7). Conclusions: About one-third of patients with RHD have AF, with an incidence which almost triples every five years after diagnosis. Factors associated with AF include age, advanced heart failure, thromboembolism, and few cardiac hemodynamics parameters.

Objective: To distinguish components of vulnerable atherosclerotic plaque by imaging their energy response using spectral CT and comparing images with histology.Methods: After spectroscopic calibration using phantoms of plaque surrogates, excised human carotid atherosclerotic plaques were imaged using MARS CT using a photon-processing detector with a silicon sensor layer and microfocus X-ray tube (50 kVp, 0.5 mA) at 38-μm voxel size. The plaques were imaged, sectioned and re-imaged using four threshold energies: 10, 16, 22 and 28 keV; then sequentially stained with modified Von Kossa, Perl's Prussian blue and Oil-Red O, and photographed. Relative Hounsfield units across the energies were entered into a linear algebraic material decomposition model to identify the unknown plaque components.Results: Lipid, calcium, iron and water-like components of plaque have distinguishable energy responses to X-ray, visible on spectral CT images. CT images of the plaque surface correlated very well with histological photographs. Calcium deposits (>1,000 μm) in plaque are larger than iron deposits (<100 μm), but could not be distinguished from each other within the same voxel using the energy range available.Conclusions: Spectral CT displays energy information in image form at high spatial resolution, enhancing the intrinsic contrast of lipid, calcium and iron within atheroma.Key Points: Spectral computed tomography offers new insights into tissue characterisation. Components of vulnerable atherosclerotic plaque are spectrally distinct with intrinsic contrast. Spectral CT of excised atherosclerotic plaques can display iron, calcium and lipid. Calcium deposits are larger than iron deposits in atheroma. Spectral CT may help in the non-invasive detection of vulnerable plaques. [ABSTRACT FROM AUTHOR]

Objective: Spectral CT differs from dual-energy CT by using a conventional X-ray tube and a photon-counting detector. We wished to produce 3D spectroscopic images of mice that distinguished calcium, iodine and barium.Methods: We developed a desktop spectral CT, dubbed MARS, based around the Medipix2 photon-counting energy-discriminating detector. The single conventional X-ray tube operated at constant voltage (75 kVp) and constant current (150 microA). We anaesthetised with ketamine six black mice (C57BL/6). We introduced iodinated contrast material and barium sulphate into the vascular system, alimentary tract and respiratory tract as we euthanised them. The mice were preserved in resin and imaged at four detector energy levels from 12 keV to 42 keV to include the K-edges of iodine (33.0 keV) and barium (37.4 keV). Principal component analysis was applied to reconstructed images to identify components with independent energy response, then displayed in 2D and 3D.Results: Iodinated and barium contrast material was spectrally distinct from soft tissue and bone in all six mice. Calcium, iodine and barium were displayed as separate channels on 3D colour images at <55 microm isotropic voxels.Conclusion: Spectral CT distinguishes contrast agents with K-edges only 4 keV apart. Multi-contrast imaging and molecular CT are potential future applications. [ABSTRACT FROM AUTHOR]

INTRODUCTION: l'infirmité motrice cérébrale (IMC) désigne un ensemble de troubles permanents de la posture et du mouvement lié à une atteinte cérébrale non progressive survenue sur le cerveau en développement du f'tus ou du nourrisson. Les troubles de la croissance sont fréquents chez les enfants souffrant d'infirmité motrice cérébrale et sont liés à des problèmes nutritionnels et non nutritionnels. METHODES: nous avons mené une étude transversale analytique dans l'unité de neuropédiatrie de l'Hôpital Gynéco-Obstétrique et Pédiatrique de Yaoundé (HGOPY) du 02 janvier 2014 au 30 juin 2014. Ce travail comportait deux volets, d'une part comparer les différents indices anthropométriques des enfants en fonction du type d'IMC et d'autre part, comparer la croissance staturo-pondérale du groupe d'enfants atteints d'IMC à celle d'un groupe d'enfants témoins appariés selon le sexe et l'âge. Les mesures anthropométriques étaient réalisées suivant les recommandations de l'OMS. Les moyennes de z-score des différents indices anthropométriques étaient calculées et comparées dans les deux groupes. RESULTATS: au total 134 cas et 134 témoins répondant à aux critères d'inclusion ont été recrutés. Le sexe ratio était de 1,62. L'âge moyen des enfants était de 2,65 (SD 2,5) ans. La tétraparésie spastique était la forme clinique la plus représentée, 55,2% des cas présentaient des troubles de l'alimentation. Quatorze (12,3%) cas souffraient d'émaciation contre 2,7% des témoins, 29 (22,2%) des cas souffraient d'insuffisance pondérale contre 4 (3%) témoins, 42 (31,3%) des cas souffraient de retard statural contre 1 (0,7%) dans le groupe témoin. L'insuffisance pondérale et le retard de croissance statural étaient plus marqués chez les enfants présentant la forme mixte d'IMC, tandis que l'émaciation prédominait chez les enfants atteints de la forme choréoathétosique. Les différents indices anthropométriques étaient d'autant plus abaissés que le niveau d'invalidité était élevé. CONCLUSION: la malnutrition est donc très fréquente dans la population d'enfants souffrant d'IMC. Cette croissance sous optimale est plus marquée chez les patients présentant la forme mixte de paralysie cérébrale et la tétraparésie spastique ainsi que chez ceux présentant un déficit moteur sévère et des troubles nutritionnels. La prise en charge de l'enfant infirme moteur cérébral devrait intégrer une prise en charge nutritionnelle.

Abstract Background Increasing rates of postpartum haemorrhage in developed countries over the past two decades are not explained by corresponding changes in risk factors and conjecture has been raised that maternal obesity may be responsible. Few studies investigating risk factors for PPH have included BMI or investigated PPH risk among nulliparous women. The aim of this study was to determine in a cohort of nulliparous women delivering at term whether overweight and obesity are independent risk factors for major postpartum haemorrhage (PPH ≥1000ml) after vaginal and caesarean section delivery. Methods The study population was nulliparous singleton pregnancies delivered at term at National Women’s Hospital, Auckland, New Zealand from 2006 to 2009 (N=11,363). Multivariable logistic regression was adjusted for risk factors for major PPH. Results There were 7238 (63.7%) women of normal BMI, 2631 (23.2%) overweight and 1494 (13.1%) obese. Overall, PPH rates were increased in overweight and obese compared with normal-weight women (n=255 [9.7%], n=233 [15.6%]), n=524 [7.2%], p Conclusion Nulliparous obese women have a twofold increase in risk of major PPH compared to women with normal BMI regardless of mode of delivery. Higher rates of PPH among obese women are not attributable to their higher rates of caesarean delivery. Obesity is an important high risk factor for PPH, and the risk following vaginal delivery is emphasised. We recommend in addition to standard practice of active management of third stage of labour, there should be increased vigilance and preparation for PPH management in obese women.

A generalized form of Landauer's bound on the dissipative cost of classical information processing in quantum-mechanical systems is proved using a new approach. This approach sidesteps some prominent objections to standard proofs of Landauer's bound-broadly interpreted here as a nonzero lower bound on the amount of energy that is irreversibly transferred from a physical system to its environment for each bit of information that is lost from the system-while establishing a far more general result. Specializations of our generalized Landauer bound for ideal and non-ideal information processing operations, including but not limited to the simplified forms for erasure and logical operations most familiar from the literature, are presented and discussed. These bounds, taken together, enable reconsideration of the links between logical reversibility, physical reversibility, and conditioning of operations in contexts that include but are far more general than the thermodynamic model systems that are most widely invoked in discussions of Landauer's Principle. Because of the strategy used to prove the generalized bounds and these specializations, this work may help to illuminate and resolve some longstanding controversies related to dissipation in computation.

Objective: To determine whether novel multi-energy spectral photon-counting computed tomography (SPCCT) imaging can detect and differentiate between monosodium urate (MSU), calcium pyrophosphate (CPP), and hydroxyapatite (HA) crystal deposits ex vivo., Methods: A finger with a subcutaneous gouty tophus and a calcified knee meniscus excised at the time of surgery were obtained. The finger was imaged using plain x-ray, dual-energy CT (DECT), and multi-energy SPCCT. Plain x-ray and multi-energy SPCCT images of the meniscus were acquired. For validation purposes, samples of the crystals were obtained from the tophus and meniscus, and examined by polarized light microscopy and/or x-ray diffraction. As further validation, synthetic crystal suspensions of MSU, CPP, and HA were scanned using multi-energy SPCCT., Results: Plain x-ray of the gouty finger revealed bone erosions with overhanging edges. DECT and multi-energy SPCCT both showed MSU crystal deposits; SPCCT was able to show finer detail. Plain x-ray of the calcified meniscus showed chondrocalcinosis consistent with CPP, while SPCCT showed and differentiated CPP and HA., Conclusion: Multi-energy SPCCT can not only detect, differentiate, and quantify MSU crystal deposits in a gouty finger ex vivo, but also specifically detect, identify, and quantify CPP within an osteoarthritic meniscus, and distinguish them from HA crystal deposits. There is potential for multi-energy SPCCT to become useful in the diagnosis of crystal arthropathies., (© 2019, American College of Rheumatology.)

Building from the cow up refers to the construction of a barn for which the foundations are the cow and her behavior, comfort, health, safety, and performance. The stall area must allow a cow to stand with all 4 feet on a comfortable bed; to rest in natural wide, narrow, short, or long positions; and to recline and rise with natural forward lunging motions. There must be no hazards that may cause injury, pain, fear, or frustration. To achieve these goals, the dimensions of a cow, her natural behaviors, and the space she occupies must be known., (Copyright © 2018 Elsevier Inc. All rights reserved.)

It is important to maximize tiestall comfort by designing and building for the cow. Optimizing cow comfort improves cow health and productivity, leading to greater producer satisfaction. Tiestall housing is the name given to dairy cattle housing where the cows are individually tethered in distinct stalls. Stalls must be designed to accommodate the size of the cow and to provide freedom of movement to reduce hock lesions while maintaining clean stalls. The stall also must accommodate easy access to feed and water as part of the stall design., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Acidification is a practical way of preserving the bacteriological quality of milk so that it can be fed to calves under free-access conditions. The objectives of this study were to evaluate how milk replacer acidification and free-access feeding affect dairy calf behavior during the first week of life. Sixteen Holstein male calves were purchased at birth and transported to the University of Guelph Kemptville Campus Dairy Education and Research Centre. Calves were randomly assigned to 1 of 4 milk feeding programs: (1) free-access (ad libitum) feeding of acidified milk replacer (22% crude protein and 17% fat, 150 g/L; FA); (2) restricted (6 L/d, 150 g/L) feeding of acidified milk replacer (RA); (3) free-access feeding of nonacidified milk replacer (FN); and (4) restricted feeding of nonacidified milk replacer (RN). Formic acid was used to acidify milk replacer to a target pH between 4.0 and 4.5. Video recordings of each calf at 1, 2, and 6 d were analyzed continuously over 24 h for all occurrences of each behavior in the ethogram. Feeding behavior observations were organized into sucking bouts, from which feeding behavior outcome variables were calculated. Calves consuming acidified milk replacer demonstrated more fragmented feeding patterns, characterized by more pauses within a sucking bout (FA, FN, RA, and RN calves = 12.4, 4.4, 13.7, and 11.9 pauses/bout, respectively) and longer sucking bout duration (FA, FN, RA, and RN calves = 8.8, 5.2, 9.3, and 8.1 min/bout, respectively), than calves fed nonacidified milk replacer. Restricted-fed calves tended to have longer sucking bouts and performed more within-bout sucks (FA, FN, RA, and RN calves = 10.7, 5.8, 13.5, and 14.1, respectively) and pauses than free-access calves. Acidification and free-access feeding did not affect lying duration. Calves assigned to the acidified feeding treatments tended to perform more grooming behavior than those fed nonacidified milk replacer (FA, FN, RA, and RN calves = 0.9, 0.5, 0.8, and 0.6 h/d, respectively). Free-access feeding did not affect grooming duration. The observed differences in feeding and grooming behavior suggest that acidification to a pH between 4.0 and 4.5 may have altered the palatability of milk replacer. Calves assigned to the acidified milk replacer feeding treatments did not, however, show avoidance toward this feedstuff during the first week of life., (Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Introduction: The neuronal ceroid lipofuscinoses (NCLs; Batten disease) are a group of fatal neurodegenerative lysosomal storage diseases of children caused by various mutations in a range of genes. Forms associated with mutations in two of these, CLN5 and CLN6, are being investigated in well-established sheep models. Brain atrophy leading to psychomotor degeneration is among the defining features, as is regional progressive ossification of the inner cranium. Ongoing viral-mediated gene therapy trials in these sheep are yielding encouraging results. In vivo assessment of brain atrophy is integral to the longitudinal monitoring of individual animals and provides robust data for translation to treatments for humans., Methods: Computed tomography (CT)-based three-dimensional reconstruction of the intracranial volume (ICV) over time reflects the progression of cortical brain atrophy, verifying the use of ICV measurements as a surrogate measure for brain size in ovine NCL., Results: ICVs of NCL-affected sheep increase for the first few months, but then decline progressively between 5 and 13 months in CLN5 -/- sheep and 11-15 months in CLN6 -/- sheep. Cerebral ventricular volumes are also increased in affected animals. To facilitate ICV measures, the radiodensities of ovine brain tissue and cerebrospinal fluid were identified. Ovine brain tissue exhibited a Hounsfield unit (HU) range of (24; 56) and cerebrospinal fluid a HU range of (-12; 23)., Conclusions: Computed tomography scanning and reconstruction verify that brain atrophy ovine CLN5 NCL originates in the occipital lobes with subsequent propagation throughout the whole cortex and these regional differences are reflected in the ICV loss., (© 2018 Lincoln University. Brain and Behavior published by Wiley Periodicals, Inc.)

Objective: We aimed to determine whether multienergy spectral photon-counting CT could distinguish between clinically relevant calcium crystals at clinical x-ray energy ranges. Energy thresholds of 15, 22, 29, and 36 keV and tube voltages of 50, 80, and 110 kVp were selected. Images were analyzed to assess differences in linear attenuation coefficients between various concentrations of calcium hydroxyapatite (54.3, 211.7, 808.5, and 1169.3 mg/cm 3 ) and calcium oxalate (2000 mg/cm 3 )., Conclusion: The two lower concentrations of hydroxyapatite were distinguishable from oxalate at all energy thresholds and tube voltages, whereas discrimination at higher concentrations depended primarily on the energy thresholds used. Multienergy spectral photon-counting CT shows promise for distinguishing these calcium crystals.

Background and Objective: To describe the clinical features, management, and immediate outcomes of patients with subretinal abscesses secondary to methicillin-resistant Staphylococcus aureus (MRSA) endogenous endophthalmitis., Patients and Methods: Eleven eyes of seven patients were identified by retrospective chart review. Demographics, initial presentation, examination findings, imaging, cultures, treatments, and short-term outcomes were reviewed., Results: Eleven eyes of seven patients presented with subretinal abscesses secondary to MRSA endogenous endophthalmitis. Four had history of recurrent MRSA infections or active soft-tissue ulceration. Six underwent vitreous tap for culture without growth. Three had positive blood cultures for MRSA. Six received empiric therapy with intravenous vancomycin, one received oral trimethoprim-sulfamethoxazole, and six received intravitreal vancomycin. Consolidation of abscesses was seen within days of initial treatment. Visual outcomes were contingent on abscess location and time to initial treatment., Conclusion: Prompt diagnosis and systemic antibiotic therapy is paramount in the treatment of this rare presentation. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:134-142.]., (Copyright 2017, SLACK Incorporated.)

The objectives of this study were to evaluate the effects of free-access acidified milk replacer feeding on the pre- and postweaning health of dairy and veal calves. Individually housed calves were systematically assigned at birth to 1 of 2 feeding programs: free-access feeding (ad libitum) of acidified milk replacer (ACD, n=249) or traditional restricted feeding (3L fed twice daily) of milk replacer (RES, n=249). Calves were fed milk replacer containing 24% crude protein and 18% fat. Acidified milk replacer was prepared to a target pH between 4.0 and 4.5 using formic acid. Calves were weaned off milk replacer at approximately 6wk of age. Weaning occurred over 5d, and during this weaning period, ACD calves had access to milk replacer for 12h/d and RES calves were offered only one feeding of milk replacer (3 L) daily. Calves were monitored daily for signs of disease. Fecal consistency scores were assigned each week from birth until weaning. A subset of calves was systematically selected for fecal sampling at 3 time points between 7 and 27d of age. Fecal samples were analyzed for enterotoxigenic Escherichia coli F5, Cryptosporidium parvum, rotavirus, and coronavirus. Hip width, hip height, body length, heart girth, and body weight were measured at birth and weaning. Postweaning body weight measurements were collected from the heifers at approximately 8mo of age. Postweaning body weight and carcass grading information was collected from the veal calves at slaughter once a live weight between 300 and 350kg had been achieved. The odds of ACD calves being treated for a preweaning disease event tended to be lower than that of the RES calves (1.2 vs. 5.2%, respectively). Preweaning mortality, postweaning disease treatment, and postweaning mortality did not differ between feeding treatments. The ACD feeding treatment supported greater preweaning average daily gain (0.59 vs. 0.43kg/d) and structural growth than RES feeding. Postweaning average daily gain and carcass characteristics were similar for ACD and RES calves. These results indicate that free-access acidified milk replacer feeding tended to support improved health, and greater body weight gain and structural growth during the preweaning period; these effects did not persist in the postweaning period. The growth advantage observed before weaning in the ACD calves likely disappeared due to the weaning methods used., (Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Objectives: To quantify iodine uptake in articular cartilage as a marker of glycosaminoglycan (GAG) content using multi-energy spectral CT., Methods: We incubated a 25-mm strip of excised osteoarthritic human tibial plateau in 50 % ionic iodine contrast and imaged it using a small-animal spectral scanner with a cadmium telluride photon-processing detector to quantify the iodine through the thickness of the articular cartilage. We imaged both spectroscopic phantoms and osteoarthritic tibial plateau samples. The iodine distribution as an inverse marker of GAG content was presented in the form of 2D and 3D images after applying a basis material decomposition technique to separate iodine in cartilage from bone. We compared this result with a histological section stained for GAG., Results: The iodine in cartilage could be distinguished from subchondral bone and quantified using multi-energy CT. The articular cartilage showed variation in iodine concentration throughout its thickness which appeared to be inversely related to GAG distribution observed in histological sections., Conclusions: Multi-energy CT can quantify ionic iodine contrast (as a marker of GAG content) within articular cartilage and distinguish it from bone by exploiting the energy-specific attenuation profiles of the associated materials., Key Points: • Contrast-enhanced articular cartilage and subchondral bone can be distinguished using multi-energy CT. • Iodine as a marker of glycosaminoglycan content is quantifiable with multi-energy CT. • Multi-energy CT could track alterations in GAG content occurring in osteoarthritis.

The energy information acquired using spectral X-ray detectors allows noninvasive identification and characterization of chemical components of a material. To achieve this, it is important that the energy response of the detector is calibrated. The established techniques for energy calibration are not practical for routine use in pre-clinical or clinical research environment. This is due to the requirements of using monochromatic radiation sources such as synchrotron, radio-isotopes, and prohibitively long time needed to set up the equipment and make measurements. To address these limitations, we have developed an automated technique for calibrating the energy response of the pixels in a spectral X-ray detector that runs with minimal user intervention. This technique uses the X-ray tube voltage (kVp) as a reference energy, which is stepped through an energy range of interest. This technique locates the energy threshold where a pixel transitions from not-counting (off) to counting (on). Similarly, we have developed a technique for calibrating the energy response of individual pixels using X-ray fluorescence generated by metallic targets directly irradiated with polychromatic X-rays, and additionally γ-rays from (241)Am. This technique was used to measure the energy response of individual pixels in CdTe-Medipix3RX by characterizing noise performance, threshold dispersion, gain variation and spectral resolution. The comparison of these two techniques shows the energy difference of 1 keV at 59.5 keV which is less than the spectral resolution of the detector (full-width at half-maximum of 8 keV at 59.5 keV). Both techniques can be used as quality control tools in a pre-clinical multi-energy CT scanner using spectral X-ray detectors.

Purpose of Review: The healthcare system creates a vast amount of data that are utilized by a wide variety of entities for a multitude of purposes. Physicians have traditionally been unable to control who has access to their data or how their data are used. The widespread adoption of the Electronic Health Record (EHR) by physicians will create a larger and more valuable healthcare data market with broad implications for the healthcare system. It is, therefore, important for physicians to understand the evolving healthcare data market and the importance of maintaining ownership of and control over their electronic health data., Recent Findings: Several entities, including private health insurance companies, federal payers, medical societies, and pharmaceutical companies are increasingly utilizing healthcare data to drive reimbursement policies and commercial initiatives., Summary: Given the critical importance that EHR data will play in multiple aspects of the healthcare industry, it is in physicians' interest to maintain ownership and control of the healthcare data that they generate. It would be prudent for physicians to exercise caution before relinquishing data rights to entities that may sell the data to payers or other customers with whom physicians' interests may not be aligned.

Spectral molecular imaging is a new X-ray-based imaging technology providing highly specific 3D imaging at high spatial resolution that has the potential to measure disease activity and response to treatment noninvasively. The ability to identify and quantify components of tissue and biomarkers of disease activity derive from the properties of the photon-processing detector. Multiple narrow sections of the energy spectrum are sampled simultaneously, providing a range of energy dependent Hounsfield units. As each material has a specific measurable X-ray spectrum, spectroscopic imaging allows for multiple materials to be quantified and differentiated from each other simultaneously. The technology, currently in its infancy, is set to grow rapidly, much as magnetic resonance did. The critical clinical applications have not yet been established, but it is likely to play a major role in identifying and directing treatment for unstable atherosclerotic plaque, assessing activity and response to treatment of a range of inflammatory diseases, and monitoring biomarkers of cancer and its treatment. If combined with Positron-emission tomography (PET), spectral molecular imaging could have a far greater effective role in cancer diagnosis and treatment monitoring than PET-CT does at present. It is currently used for small animal and specimen imaging. There are many challenges to be overcome before spectral imaging can be introduced into clinical medicine - these include technological improvements to detector design, bonding to the semiconductor layer, image reconstruction and display software, identifying which biomarkers are of most relevance to the disease in question, and accelerating drug discovery enabled by the new capabilities provided by spectral imaging., (Copyright © 2014 John Wiley & Sons, Ltd.)

Purpose: To report the clinical and pathologic findings in a patient with a primary Acanthamoeba subretinal abscess., Methods: A healthy 40-year-old man was evaluated and treated for a subretinal abscess. A subretinal aspirate was evaluated using hematoxylin-eosin stains and polymerase chain reaction., Results: Results of the histologic examination of the subretinal aspirate demonstrated numerous Acanthamoeba cysts. The diagnosis was confirmed by polymerase chain reaction. The infection was treated with local and systemic antimicrobials. The visual acuity remained stable, and there was no local or systemic spread of the infection., Conclusion: To the authors' knowledge, this is the first biopsy-proven case of primary subretinal abscess because of Acanthamoeba. Acanthamoeba should be considered in the differential diagnosis of a subretinal abscess, even in the absence of systemic or corneal symptoms. Aggressive treatment can prevent serious ocular and systemic complications.

Purpose: To determine the potential of spectral computed tomography (CT) with Medipix3 for quantifying fat, calcium, and iron in soft tissues within small animal models and surgical specimens of diseases such as fatty liver (metabolic syndrome) and unstable atherosclerosis., Methods: The spectroscopic method was applied to tomographic data acquired using a micro-CT system incorporating a Medipix3 detector array with silicon sensor layer and microfocus x-ray tube operating at 50 kVp. A 10 mm diameter perspex phantom containing a fat surrogate (sunflower oil) and aqueous solutions of ferric nitrate, calcium chloride, and iodine was imaged with multiple energy bins. The authors used the spectroscopic characteristics of the CT number to establish a basis for the decomposition of soft tissue components. The potential of the method of constrained least squares for quantifying different sets of materials was evaluated in terms of information entropy and degrees of freedom, with and without the use of a volume conservation constraint. The measurement performance was evaluated quantitatively using atheroma and mouse equivalent phantoms. Finally the decomposition method was assessed qualitatively using a euthanized mouse and an excised human atherosclerotic plaque., Results: Spectral CT measurements of a phantom containing tissue surrogates confirmed the ability to distinguish these materials by the spectroscopic characteristics of their CT number. The assessment of performance potential in terms of information entropy and degrees of freedom indicated that certain sets of up to three materials could be decomposed by the method of constrained least squares. However, there was insufficient information within the data set to distinguish calcium from iron within soft tissues. The quantification of calcium concentration and fat mass fraction within atheroma and mouse equivalent phantoms by spectral CT correlated well with the nominal values (R(2) = 0.990 and R(2) = 0.985, respectively). In the euthanized mouse and excised human atherosclerotic plaque, regions of calcium and fat were appropriately decomposed according to their spectroscopic characteristics., Conclusions: Spectral CT, using the Medipix3 detector and silicon sensor layer, can quantify certain sets of up to three materials using the proposed method of constrained least squares. The system has some ability to independently distinguish calcium, fat, and water, and these have been quantified within phantom equivalents of fatty liver and atheroma. In this configuration, spectral CT cannot distinguish iron from calcium within soft tissues.

Simplified analysis systems that offer the performance of benchtop instruments but the convenience of portability are highly desirable. We have developed novel, miniature devices that feature visual inspection readout of a target's concentration from a ~1 μL volume of solution introduced into a microfluidic channel. Microchannels are constructed within an elastomeric material, and channel surfaces are coated with receptors to the target. When a solution is flowed into the channel, the target cross-links multiple receptors on the surface, resulting in constriction of the first few millimeters of the channel and stopping of flow. Quantitation is performed by measuring the distance traveled by the target solution in the channel before flow stops. A key advantage of our approach is that quantitation is accomplished by simple visual inspection of the channel, without the need for complex detection instrumentation. We have tested these devices using the model system of biotin as a receptor and streptavidin as the target. We have also characterized three factors that influence flow distance: solution viscosity, device thickness, and channel height. We found that solution capillary flow distance scales with the negative logarithm of target concentration and have detected streptavidin concentrations as low as 1 ng/mL. Finally, we have identified and evaluated a plausible mechanism wherein time-dependent channel constriction in the first few millimeters leads to concentration-dependent flow distances. Their simplicity coupled with performance makes these "flow valve" systems especially attractive for a host of analysis applications.

Purpose: To assess accuracy of ultrasonographic (US) follow-up of distal ureteral calculi by using computed tomography (CT) and conventional radiography (kidneys, ureters, and bladder) as reference standards., Materials and Methods: The study was approved by the Regional Ethics Committee, and written informed consent was obtained. One hundred fifty-eight patients with CT-diagnosed symptomatic ureteral calculi, for whom follow-up imaging was ordered, were enrolled from February 2006 to December 2008. Six were excluded, having not met study entry criteria, with 121 men (mean age, 49 years; range, 20-91 years) and 31 women (mean age, 44 years; range, 34-77 years) completing the protocol with adequate reference standard imaging. Targeted transabdominal US occurred coincidently with follow-up CT (n = 92) or radiography (n = 60), with US evaluation prospectively compared considering sensitivity and specificity. Statistical analysis was performed with a χ(2) test, t test, or paired t test, as appropriate., Results: Results of nine US examinations were nondiagnostic because of inadequate ureteral visualization, and among these, two cases showed residual distal calculi. Of the remaining 143 patients, 33 had residual distal calculi, all visualized with US. There was a single false-positive study, giving sensitivity, including nondiagnostic US examinations, of 94.3% (95% confidence interval [CI]: 80.8%, 99.3%) and specificity of 99.1% (95% CI: 95.3%, 100%). All calculi appeared hyperechoic with posterior acoustic shadowing. Additional diagnostic features included presence of a hypoechoic rim and Doppler twinkle artifact. Mean stone length was 7.2 mm ± 2.6 (standard deviation) (range, 4-18 mm). Mean ureteral length visualized was 36.4 mm (range, 12-77 mm), with calculi positioned at a mean of 13.1 mm ± 11.2 (range, 0-40 mm) from the ureterovesical junction (UVJ). Nondiagnostic results were more likely with bladder volume of 110 mL or less (eight [16%] of 50 vs one [1%] of 102, P = .0009)., Conclusion: Ureteral calculi within 35 mm of the UVJ can be accurately followed-up by using transabdominal US, which substantially reduces patient radiation burden., (© RSNA, 2011.)

Purpose: The purpose of this study was to determine the incidence of infectious endophthalmitis after intravitreal injection of antivascular endothelial growth factor medications using 2% topical lidocaine gel anesthesia., Methods: Retrospective chart review of 4690 consecutive intravitreal injections of antivascular endothelial growth factor medications using 2% topical lidocaine gel anesthesia. All patients had at least 6 weeks of follow-up., Results: A total of 608 patients underwent intravitreal injection of antivascular endothelial growth factor medications during the study period. There were 428 injections of pegaptanib sodium, 1841 injections of bevacizumab, and 2421 injections of ranibizumab. There were no cases of infectious endophthalmitis. The per-injection infection rate was 0.0% (95% confidence interval, 0.0-0.06%)., Conclusion: The incidence of infectious endophthalmitis after intravitreal injection of antivascular endothelial growth factor medications using 2% topical lidocaine gel anesthesia is low.

Infants with mild postnatal renal dilatation but without vesicoureteral reflux pose a challenge. For how long and in what way should they be followed? From May 1989 to December 2006, we prospectively followed 1,795 pregnancies in which the foetal renal pelvis measured 4 mm or greater. Voiding cystourethrography (VCUG) and renal ultrasound were performed on 1,315 infants at 6 weeks of age. Our study group comprised 208 (167 male) infants with normal VCUG findings who had a renal pelvis of 6-11 mm. We followed them for 1-17 years (mean 11 years). Medical and radiological records were reviewed to determine any urinary symptoms and final outcome. They underwent, on average, four further imaging tests. The renal dilatation had resolved by 24 months in approximately 70%. Urinary tract infection (UTI) developed in 16 (8%). Calyceal dilatation was more likely in those developing UTI (P=0.02). Twenty-two (10.6%) had a radiologically demonstrated urinary tract abnormality. Of the five who had renal scarring or severe obstruction, four became symptomatic. Most infants with mild postnatal renal dilatation can be investigated with only one further sonogram at 24 months of age. Mild postnatal renal dilatation is associated with subsequent UTI or renal tract abnormality in 18%. Severe renal abnormality occurred in 2.4%.

Freshwater lakes and ponds present an ecological interface between humans and a variety of host organisms. They are a habitat for the larval stage of many insects and may serve as a medium for intraspecies and interspecies transmission of viruses such as avian influenza A virus. Furthermore, freshwater bodies are already known repositories for disease-causing viruses such as Norwalk Virus, Coxsackievirus, Echovirus, and Adenovirus. While RNA virus populations have been studied in marine environments, to this date there has been very limited analysis of the viral community in freshwater. Here we present a survey of RNA viruses in Lake Needwood, a freshwater lake in Maryland, USA. Our results indicate that just as in studies of other aquatic environments, the majority of nucleic acid sequences recovered did not show any significant similarity to known sequences. The remaining sequences are mainly from viral types with significant similarity to approximately 30 viral families. We speculate that these novel viruses may infect a variety of hosts including plants, insects, fish, domestic animals and humans. Among these viruses we have discovered a previously unknown dsRNA virus closely related to Banna Virus which is responsible for a febrile illness and is endemic to Southeast Asia. Moreover we found multiple viral sequences distantly related to Israeli Acute Paralysis virus which has been implicated in honeybee colony collapse disorder. Our data suggests that due to their direct contact with humans, domestic and wild animals, freshwater ecosystems might serve as repositories of a wide range of viruses (both pathogenic and non-pathogenic) and possibly be involved in the spread of emerging and pandemic diseases.

The lack of sensitive, specific, multiplexable assays for most human proteins is the major technical barrier impeding development of candidate biomarkers into clinically useful tests. Recent progress in mass spectrometry-based assays for proteotypic peptides, particularly those with specific affinity peptide enrichment, offers a systematic and economical path to comprehensive quantitative coverage of the human proteome. A complete suite of assays, e.g. two peptides from the protein product of each of the approximately 20,500 human genes (here termed the human Proteome Detection and Quantitation project), would enable rapid and systematic verification of candidate biomarkers and lay a quantitative foundation for subsequent efforts to define the larger universe of splice variants, post-translational modifications, protein-protein interactions, and tissue localization.

Objective: The purpose of this study was to describe normal sonographic appearances of the endometrium in asymptomatic women after elective termination of pregnancy (TOP) and to determine whether sonographic findings are discriminatory in symptomatic women after TOP., Methods: Sonographic parameters were compared in prospectively recruited women after elective TOP. The first 38 were asymptomatic. In a later group, 105 had symptoms suggestive of retained products of conception (RPOC). Endometrial thickness, cavity irregularity, echogenicity of cavity contents, color Doppler flow, and resistive indices (RIs) were assessed. In the symptomatic group, sonographic findings were correlated with symptoms and histologic results., Results: There was a marked overlap in sonographic appearances between the groups. The endometrial cavity is commonly irregular and thickened and may show prominent color Doppler flow in women with an uneventful course as well as in women with histologically proven RPOC. Differences between asymptomatic and symptomatic women were only seen for: endometrial thickness (10.8 mm [range, 1-29 mm] versus 15.3 mm [range, 1.8-34 mm]; P = .0005), and cavity irregularity was greater in symptomatic women (P = .001). Color Doppler flow mean RIs were similar. Symptoms were similar in women proceeding to curettage versus no curettage; no significant relationship was found between individual symptoms and sonographic parameters. Chorionic villi were seen in 47 of 56 women (84%) with positive histologic results., Conclusions: Sonographic appearances and symptoms correlate poorly with each other and with histologic results. Sonography has limited benefits in triaging women with suspected RPOC after TOP in the first trimester. Our findings support a more conservative approach to suspected RPOC after TOP.

Objectives: Assessing fetal liver size might be useful in monitoring the effectiveness of the treatment of diabetes in pregnancy. We aimed to assess the reproducibility of fetal liver-length measurement in pregnant women with diabetes., Methods: From 3 April 2006 to 5 December 2006, we assessed intraobserver and interobserver variation of fetal liver-length measurements on 55 sonograms in 44 pregnant women with diabetes, 34 of whom had gestational diabetes. The mean maternal age was 33 years, the mean maternal weight was 92 kg and the mean body mass index (BMI) was 33.7 kg/m(-2). The effect of covariates BMI, gestational age and maternal age on the reproducibility of fetal liver length was assessed by calculating intraobserver SD ratios. We compared liver length with abdominal circumference and gestational age. Nine of 12 sonographers scanned, on average, six women (range, 3-12) as the first sonographer, and all 12 sonographers scanned, on average, four women (range, 1-10) as the second sonographer. The data were analyzed using a hierarchical linear model., Results: Measurement of fetal liver length was reproducible. The intraobserver SD was 3.06 (95% CI, 2.68-3.59) mm; the interobserver SD was 2.17 (95% CI, 0.59-4.83) mm; the intraobserver correlation was 0.77 (95% CI, 0.63-0.87), and the interobserver correlation was 0.84 (95% CI, 0.51-0.99). The covariate effects were minimal, the SD for a 1-unit increase in the covariate was 1.06 for gestational age, 0.98 for BMI, and 0.97 for maternal age., Conclusions: Measurement of fetal liver length in the diabetic pregnancy is reproducible. It is worthy of further investigation as a parameter for monitoring the effectiveness of treatment of the diabetic pregnancy., (Copyright (c) 2008 ISUOG)

Background: Most emerging health threats are of zoonotic origin. For the overwhelming majority, their causative agents are RNA viruses which include but are not limited to HIV, Influenza, SARS, Ebola, Dengue, and Hantavirus. Of increasing importance therefore is a better understanding of global viral diversity to enable better surveillance and prediction of pandemic threats; this will require rapid and flexible methods for complete viral genome sequencing., Results: We have adapted the SISPA methodology 123 to genome sequencing of RNA and DNA viruses. We have demonstrated the utility of the method on various types and sources of viruses, obtaining near complete genome sequence of viruses ranging in size from 3,000-15,000 kb with a median depth of coverage of 14.33. We used this technique to generate full viral genome sequence in the presence of host contaminants, using viral preparations from cell culture supernatant, allantoic fluid and fecal matter., Conclusion: The method described is of great utility in generating whole genome assemblies for viruses with little or no available sequence information, viruses from greatly divergent families, previously uncharacterized viruses, or to more fully describe mixed viral infections.

Objectives: To determine the major sources of error in ultrasonographic assessment of fetal weight and whether they have changed over the last decade., Methods: We performed a prospective observational study in 1991 and again in 2000 of a mixed-risk pregnancy population, estimating fetal weight within 7 days of delivery. In 1991, the Rose and McCallum formula was used for 72 deliveries. Inter- and intraobserver agreement was assessed within this group. Bland-Altman measures of agreement from log data were calculated as ratios. We repeated the study in 2000 in 208 consecutive deliveries, comparing predicted and actual weights for 12 published equations using Bland-Altman and percentage error methods. We compared bias (mean percentage error), precision (SD percentage error), and their consistency across the weight ranges., Results: 95% limits of agreement ranged from - 4.4% to + 3.3% for inter- and intraobserver estimates, but were - 18.0% to 24.0% for estimated and actual birth weight. There was no improvement in accuracy between 1991 and 2000. In 2000 only six of the 12 published formulae had overall bias within 7% and precision within 15%. There was greater bias and poorer precision in nearly all equations if the birth weight was < 1,000 g., Conclusions: Observer error is a relatively minor component of the error in estimating fetal weight; error due to the equation is a larger source of error. Improvements in ultrasound technology have not improved the accuracy of estimating fetal weight. Comparison of methods of estimating fetal weight requires statistical methods that can separate out bias, precision and consistency. Estimating fetal weight in the very low birth weight infant is subject to much greater error than it is in larger babies., (Copyright (c) 2007 ISUOG. Published by John Wiley & Sons, Ltd.)