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Smith A, Glynn AC, Shankar A, McDermott C, McCallion N. A Review of the Parenteral Nutrition Supply Service in an Irish Neonatal Unit. IRISH MEDICAL JOURNAL 2018; 111:778. [PMID: 30450889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Background Neonatal Intensive Care (NICU) patients have individual nutritional requirements often requiring Patient Specific Parenteral Nutrition (PSPN). From October 2015, the national PSPN compounding service availability changed from 7 days per week service to 5 days per week (i.e. no weekend and limited bank holiday ordering available). The aim of this study was to examine the introduction of a 5 day only PSPN supply on neonatal patient parenteral nutrition availability in a tertiary NICU. Methods We performed a prospective assessment of the provision of a 5 day rather than 7 day ordering of PSPN over a one month period (June 2017). Results Fifteen neonatal patients received a cumulative 89 days of PN during June 2017. 10 (66%) patients received PSPN during this time period. There was same day availability of PSPN in 62 of 89 days of PN (69%). Conclusion Thorough education and training will help prescribers to make appropriate PSPN ordering decisions. Improvements to available stock bags may reduce the amount of PSPN that is required but a 7 day PSPN ordering service would improve efficient provision of clinically indicated PSPN to premature infants in NICU in Ireland.
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Smith A, Shankar A, Collins A, Tarrant A, Boyle MA. The Triangular Sign, a Useful Diagnostic Marker for Biliary Atresia: A Case Series of Three Irish Infants. IRISH MEDICAL JOURNAL 2018; 111:776. [PMID: 30450888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Background The triangular cord (TC) sign is the appearance of a triangular shaped echogenic density visualised immediately cranial to the portal vein bifurcation on ultrasonographic examination. Several studies have reported that this ultrasonographic sign is a reliable and helpful marker in identifying Biliary Atresia (BA). Aims To report the identification of the TC sign in three infants with BA in the Rotunda Hospital, Dublin. Methods A retrospective chart review was performed to evaluate the clinical presentation and imaging of the three patients with positive TC sign and BA. Discussion Timely, accurate diagnosis of BA is essential to minimise morbidity and optimise patient outcome. The TC is a valuable ultrasonographic sign to aid early diagnosis of BA.
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Nimkar S, Valvi C, Kadam D, Rewari BB, Kinikar A, Gupte N, Suryavanshi N, Deluca A, Shankar A, Golub J, Bollinger R, Gupta A, Marbaniang I, Mave V. Loss to follow-up and mortality among HIV-infected adolescents receiving antiretroviral therapy in Pune, India. HIV Med 2018; 19:395-402. [PMID: 29573312 DOI: 10.1111/hiv.12605] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/12/2018] [Indexed: 11/29/2022]
Abstract
OBJECTIVES India has the highest number of HIV-infected adolescents in Asia, but little is known about their treatment outcomes. We assessed rates and factors associated with loss to follow-up (LTFU) and mortality among Indian adolescents. METHODS The analysis included adolescents (10-19 years old) starting antiretroviral therapy (ART) between 2005 and 2014 at BJ Government Medical College, Pune, India. LTFU was defined as missing more than three consecutive monthly visits. The competing-risks method was used to calculate subdistribution hazard ratios (SHRs) of predictors for LTFU, with death as the competing risk. Cox proportional hazard models were used to identify predictors of mortality. RESULTS Of 717 adolescents starting ART, 402 with complete data were included in the analysis. Of these, 61% were male and 80% were perinatally infected, and the median baseline CD4 count was 174 cells/μL. LTFU and mortality rates were 4.4 and 4.9/100-person years, respectively. Cumulative LTFU incidence increased from 6% to 15% over 6 years. Age ≥ 15 years [adjusted SHR (aSHR) 2.44; 95% confidence interval (CI) 1.18-5.02] was a risk factor for LTFU. Cumulative mortality increased from 9.5% to 17.9% over 6 years. World Health Organization (WHO) stages III and IV [adjusted hazard ratio (aHR) 2.26; 95% CI: 1.14-4.48] and an increase in CD4 count by 100 cells/μL (aHR: 0.59; 95% CI: 0.43-0.83) were associated with mortality. CONCLUSIONS A third of adolescents had been lost to follow-up or died by follow-up year 6. Older age was a risk factor for LTFU and advanced clinical disease for death. Strategies to improve retention counselling for older adolescents and closer clinical monitoring of all adolescents must be considered.
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Krebs J, Shankar A, Bednarek DR, Rudin S. Gantry rotational motion-induced blur in cone-beam computed tomography. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2018; 10573:105734B. [PMID: 29928070 PMCID: PMC6004603 DOI: 10.1117/12.2293580] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
As neuro-endovascular image-guided interventions (EIGIs) make use of higher resolution detectors, gantry rotational motion-induced blur becomes more noticeable in acquired projections as well as reconstructed images by reducing the visibility of vascular and device features whose visualization could be critical in the treatment of vascular pathology. Motion-induced blur in projections views is a function of an object's position in the field-of-view (FOV), gantry rotational speed, and frame capture or exposure time. In this work different frame rates were used to investigate the effects of blurring from individual projections on the reconstructed image. To test the effects of these parameters on reconstructed images, a regular pattern phantom of small objects was simulated and projection views were generated at various different frame rates for a given simulated rotational velocity. The reconstruction was made using a linear interpolation of filtered backprojections. Images reconstructed from lower frame rates showed significant blurring in the azimuthal direction, increasingly worse towards the periphery of the image. However, those reconstructed from higher frame rates showed significantly less blur throughout the entire FOV. While lower frame rates could be used with slower gantry speeds this would increase the risk of voluntary or involuntary patient motion contributing to blur over the entire FOV. A high frame rate used with high gantry speeds could reliable provide images without gantry-motion blur while reducing the risk of patient-motion blur. Frame rates exceeding 2000 fps available with photon counting detectors such as the X-counter Actaeon1 are available.
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Shankar A, Krebs J, Bednarek DR, Rudin S. Evaluation of a new photon-counting imaging detector (PCD) with various acquisition modes. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2018; 10573:105734Y. [PMID: 29881136 PMCID: PMC5987190 DOI: 10.1117/12.2294629] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The prospect of improved low noise, high speed, and dual-energy imaging that may be associated with the use of photon-counting imaging detectors (PCD) has motivated this evaluation of a newly upgraded version of a prototype PCD. The XCounter Actaeon was evaluated in its four acquisition modes each based upon varying signal processing firmware including a mode with charge sharing correction that enables neighboring pixels that share the energy from one incident x-ray photon detection to be counted only once at the proper summed energy in the pixel with the largest charge deposition. Since this PCD is a CdTe-based direct detector with 100 μm pixels, such charge sharing for typical medical x-ray energy photons may occur frequently and must be corrected to achieve more accurate counts. This charge sharing correction is achieved with an Anti-Coincidence Circuit (ACC) which prevents double pixel counting from one event as well as prevents counting from either event if they are below a preset threshold. Various physical parameters of the PCD were evaluated including linearity, sensitivity, pulse pile-up effects, dark noise, spatial resolution, noise power spectrum, and detective quantum efficiency.
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Valente R, Lykoudis P, Tamburrino D, Inama M, Passas I, Toumpanakis C, Luong TV, Davidson B, Imber C, Malagò M, Rahman SH, Shankar A, Sharma D, Caplin M, Fusai G. Major postoperative complications after pancreatic resection for P-NETS are not associated to earlier recurrence. Eur J Surg Oncol 2017; 43:2119-2128. [PMID: 28821361 DOI: 10.1016/j.ejso.2017.07.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 07/17/2017] [Accepted: 07/17/2017] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The oncological impact of surgical complications has been studied in visceral and pancreatic cancer. AIM To investigate the impact of complications on tumour recurrence after resections for pancreatic neuroendocrine tumours. METHODS We have retrospectively analysed 105 consecutive resections performed at the Royal Free London Hospital from 1998 to 2014, and studied the long-term outcome of nil-minor (<3) versus major (≥3) Clavien-Dindo complications (CD) on disease-free (DFS) and overall survival (OS). RESULTS The series accounted for 41 (39%) pancreaticoduodenectomies, two (1.9%) central, 48 (45.7%) distal pancreatectomies, eight (7.6%) enucleations, four (3.8%) total pancreatectomies. Sixteen (15.2%) were extended to adjacent organs, 13 (12.3%) to minor liver resections. Postoperative complications presented in 43 (40.1%) patients; CD grade 1 or 2 in 23 (21.9%), grades ≥3 in 20 (19%). Among 25 (23.8%) pancreatic fistulas, 14 (13.3%) were grades B or C. Thirty-four (32.4%) patients developed exocrine, and 31 (29.5%) endocrine insufficiency. Seven patients died during a median 27 (0-175) months follow up. Thirty-day mortality was 0.9%. OS was 94.1% at 5 years. Thirty tumours recurred within 11.7 (0.8-141.5) months. DFS was 44% at 5 years. At univariate analysis, high-grade complications were not associated with shorter DFS (p = 0.744). At multivariate analysis, no parameter was independent predictor for DFS or OS. The comparison of nil-minor versus major complications showed no DFS difference (p = 0.253). CONCLUSION From our series, major complications after P-NETs resection are not associated to different disease recurrence; hence do not require different follow up or adjuvant regimens.
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Bulwer C, Conn R, Shankar A, Ferrau F, Kapur S, Ederies A, Korbonits M, Spoudeas HA. Cabergoline-related impulse control disorder in an adolescent with a giant prolactinoma. Clin Endocrinol (Oxf) 2017; 86:862-864. [PMID: 28346715 DOI: 10.1111/cen.13339] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 03/19/2017] [Accepted: 03/22/2017] [Indexed: 11/30/2022]
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Shankar A, Dracham C, Ghoshal S, Grover S. Prevalence of depression and anxiety disorder in cancer patients: An institutional experience. Indian J Cancer 2017; 53:432-434. [PMID: 28244477 DOI: 10.4103/0019-509x.200651] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIM This study aimed to screen the patients with various malignancies for the presence of depressive disorders and anxiety disorder using standardized rating scales. MATERIALS AND METHODS Five hundred and thirty-four (n = 534) patients attending the radiotherapy outpatient services completed the Patient Health Questionnaire-9 and Generalized Anxiety Disorder-7 (GAD-7) Questionnaire. RESULTS About half (n = 248; 46.4%) of the patients had psychiatric morbidity either in the form of depressive disorder or in the form of GAD. Higher stage of malignancy (from early, advanced to metastasis) was associated with higher prevalence of depressive disorder and GAD. The presence of psychiatric morbidity, especially anxiety disorder, was associated with being from low socioeconomic status. CONCLUSION The present study suggests that psychiatric morbidity in the form of depressive and anxiety disorders is very common among patients with malignancies. Accordingly, there is a need for close liaison between oncologists and mental health professionals to improve the outcome of patients with various malignancies.
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Russ M, Shankar A, Setlur Nagesh SV, Ionita CN, Bednarek DR, Rudin S. Focal spot size reduction using asymmetric collimation to enable reduced anode angles with a conventional angiographic x-ray tube for use with high resolution detectors. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2017; 10132. [PMID: 28603334 DOI: 10.1117/12.2253724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The high-resolution requirements for neuro-endovascular image-guided interventions (EIGIs) necessitate the use of a small focal-spot size; however, the maximum tube output limits for such small focal-spot sizes may not enable sufficient x-ray fluence after attenuation through the human head to support the desired image quality. This may necessitate the use of a larger focal spot, thus contributing to the overall reduction in resolution. A method for creating a higher-output small effective focal spot based on the line-focus principle has been demonstrated and characterized. By tilting the C-arm gantry, the anode-side of the x-ray field-of-view is accessible using a detector placed off-axis. This tilted central axis diminishes the resultant focal spot size in the anode-cathode direction by the tangent of the effective anode angle, allowing a medium focal spot to be used in place of a small focal spot with minimal losses in resolution but with increased tube output. Images were acquired of two different objects at the central axis, and with the C-arm tilted away from the central axis at 1° increments from 0°-7°. With standard collimation settings, only 6° was accessible, but using asymmetric extended collimation a maximum of 7° was accessed for enhanced comparisons. All objects were positioned perpendicular to the anode-cathode direction and images were compared qualitatively. The increasing advantage of the off-axis focal spots was quantitatively evidenced at each subsequent angle using the Generalized Measured-Relative Object Detectability metric (GM-ROD). This anode-tilt method is a simple and robust way of increasing tube output for a small field-of-view detector without diminishing the overall apparent resolution for neuro-EIGIs.
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Russ M, Shankar A, Setlur Nagesh SV, Ionita CN, Bednarek DR, Rudin S. A CMOS-based high resolution fluoroscope (HRF) detector prototype with 49.5 μm pixels for use in endovascular image guided interventions (EIGI). PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2017; 10132. [PMID: 28615792 DOI: 10.1117/12.2253745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
X-ray detectors to meet the high-resolution requirements for endovascular image-guided interventions (EIGIs) are being developed and evaluated. A new 49.5-micron pixel prototype detector is being investigated and compared to the current suite of high-resolution fluoroscopic (HRF) detectors. This detector featuring a 300-micron thick CsI(Tl) scintillator, and low electronic noise CMOS readout is designated the HRF-CMOS50. To compare the abilities of this detector with other existing high resolution detectors, a standard performance metric analysis was applied, including the determination of the modulation transfer function (MTF), noise power spectra (NPS), noise equivalent quanta (NEQ), and detective quantum efficiency (DQE) for a range of energies and exposure levels. The advantage of the smaller pixel size and reduced blurring due to the thin phosphor was exemplified when the MTF of the HRF-CMOS50 was compared to the other high resolution detectors, which utilize larger pixels, other optical designs or thicker scintillators. However, the thinner scintillator has the disadvantage of a lower quantum detective efficiency (QDE) for higher diagnostic x-ray energies. The performance of the detector as part of an imaging chain was examined by employing the generalized metrics GMTF, GNEQ, and GDQE, taking standard focal spot size and clinical imaging parameters into consideration. As expected, the disparaging effects of focal spot unsharpness, exacerbated by increasing magnification, degraded the higher-frequency performance of the HRF-CMOS50, while increasing scatter fraction diminished low-frequency performance. Nevertheless, the HRF-CMOS50 brings improved resolution capabilities for EIGIs, but would require increased sensitivity and dynamic range for future clinical application.
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Shankar A, Safronov AP, Beketov I. Encapsulation of metallic iron magnetic nanoparticles by polyacrylamide in water suspensions. CHIMICA TECHNO ACTA 2017. [DOI: 10.15826/chimtech.2017.4.3.01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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Shankar A, Safronov AP, Beketov I. Encapsulation of metallic iron magnetic nanoparticles by polyacrylamide in water suspensions. CHIMICA TECHNO ACTA 2017. [DOI: 10.15826/chimtech/2017.4.3.01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Shankar A, Allan CLM, Smyth D, Jardine D. Cardiac cephalgia: a diagnostic headache. Intern Med J 2016; 46:1219-1221. [PMID: 27734618 DOI: 10.1111/imj.13217] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 04/10/2016] [Accepted: 04/14/2016] [Indexed: 11/27/2022]
Abstract
A 73-year-old man presented with a 6-month history of exertional headaches. Exercise tolerance test demonstrated progressive ischaemic changes concomitant with worsening headache. Cardiac cephalgia was diagnosed and his symptoms resolved after coronary artery bypass surgery. Cardiac cephalgia may occasionally present as exertional headache without chest symptoms.
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Rai DP, Chettri S, Shankar A, Patra PK, Thapa RK. A Comparative Study of 1D Monatomic Fe-chain and 3D Fe-bulk within the Density Functional Theory (DFT). ACTA ACUST UNITED AC 2016. [DOI: 10.13189/nn.2016.040301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Shankar A, Rai D, Chettri S, Khenata R, Thapa R. FP-LAPW calculations of the elastic, electronic and thermoelectric properties of the filled skutterudite CeRu4Sb12. J SOLID STATE CHEM 2016. [DOI: 10.1016/j.jssc.2016.05.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Shankar A, Russ M, Vijayan S, Bednarek D, Rudin S. TU-FG-209-02: Effective Elimination of Aliased Signal Using An Apodized Aperture Pixel Design. Med Phys 2016. [DOI: 10.1118/1.4957572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Vijayan S, Xiong Z, Shankar A, Rudin S, Bednarek D. TU-D-209-02: A Backscatter Point Spread Function for Entrance Skin Dose Determination. Med Phys 2016. [DOI: 10.1118/1.4957503] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Russ M, Shankar A, Lau A, Bednarek D, Rudin S. TU-FG-209-05: Demonstration of the Line Focus Principle Using the Generalized Measured-Relative Object Detectability (GM-ROD) Metric. Med Phys 2016. [DOI: 10.1118/1.4957575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Rana R, Jain A, Shankar A, Bednarek DR, Rudin S. Scatter estimation and removal of anti-scatter grid-line artifacts from anthropomorphic head phantom images taken with a high resolution image detector. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2016. [PMID: 28649162 DOI: 10.1117/12.2216833] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
In radiography, one of the best methods to eliminate image-degrading scatter radiation is the use of anti-scatter grids. However, with high-resolution dynamic imaging detectors, stationary anti-scatter grids can leave grid-line shadows and moiré patterns on the image, depending upon the line density of the grid and the sampling frequency of the x-ray detector. Such artifacts degrade the image quality and may mask small but important details such as small vessels and interventional device features. Appearance of these artifacts becomes increasingly severe as the detector spatial resolution is improved. We have previously demonstrated that, to remove these artifacts by dividing out a reference grid image, one must first subtract the residual scatter that penetrates the grid; however, for objects with anatomic structure, scatter varies throughout the FOV and a spatially differing amount of scatter must be subtracted. In this study, a standard stationary Smit-Rontgen X-ray grid (line density - 70 lines/cm, grid ratio - 13:1) was used with a high-resolution CMOS detector, the Dexela 1207 (pixel size - 75 micron) to image anthropomorphic head phantoms. For a 15 × 15cm FOV, scatter profiles of the anthropomorphic head phantoms were estimated then iteratively modified to minimize the structured noise due to the varying grid-line artifacts across the FOV. Images of the anthropomorphic head phantoms taken with the grid, before and after the corrections, were compared demonstrating almost total elimination of the artifact over the full FOV. Hence, with proper computational tools, anti-scatter grid artifacts can be corrected, even during dynamic sequences.
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Russ M, Shankar A, Jain A, Setlur Nagesh SV, Ionita CN, Scott C, Karim KS, Bednarek DR, Rudin S. Quantitative comparison using Generalized Relative Object Detectability (G-ROD) metrics of an amorphous selenium detector with high resolution Microangiographic Fluoroscopes (MAF) and standard flat panel detectors (FPD). PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2016; 9783. [PMID: 28615795 DOI: 10.1117/12.2216733] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
A novel amorphous selenium (a-Se) direct detector with CMOS readout has been designed, and relative detector performance investigated. The detector features include a 25μm pixel pitch, and 1000μm thick a-Se layer operating at 10V/μm bias field. A simulated detector DQE was determined, and used in comparative calculations of the Relative Object Detectability (ROD) family of prewhitening matched-filter (PWMF) observer and non-prewhitening matched filter (NPWMF) observer model metrics to gauge a-Se detector performance against existing high resolution micro-angiographic fluoroscopic (MAF) detectors and a standard flat panel detector (FPD). The PWMF-ROD or ROD metric compares two x-ray imaging detectors in their relative abilities in imaging a given object by taking the integral over spatial frequencies of the Fourier transform of the detector DQE weighted by an object function, divided by the comparable integral for a different detector. The generalized-ROD (G-ROD) metric incorporates clinically relevant parameters (focal-spot size, magnification, and scatter) to show the degradation in imaging performance for detectors that are part of an imaging chain. Preliminary ROD calculations using simulated spheres as the object predicted superior imaging performance by the a-Se detector as compared to existing detectors. New PWMF-G-ROD and NPWMF-G-ROD results still indicate better performance by the a-Se detector in an imaging chain over all sphere sizes for various focal spot sizes and magnifications, although a-Se performance advantages were degraded by focal spot blurring. Nevertheless, the a-Se technology has great potential to provide breakthrough abilities such as visualization of fine details including of neuro-vascular perforator vessels and of small vascular devices.
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Shaaban S, Alsulami M, Arbab SA, Ara R, Shankar A, Iskander A, Angara K, Jain M, Bagher-Ebadian H, Achyut BR, Arbab AS. Targeting Bone Marrow to Potentiate the Anti-Tumor Effect of Tyrosine Kinase Inhibitor in Preclinical Rat Model of Human Glioblastoma. ACTA ACUST UNITED AC 2016; 12:69-81. [PMID: 27429653 DOI: 10.3923/ijcr.2016.69.81] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Antiangiogenic agents caused paradoxical increase in pro-growth and pro-angiogenic factors and caused tumor growth in glioblastoma (GBM). It is hypothesized that paradoxical increase in pro-angiogenic factors would mobilize Bone Marrow Derived Cells (BMDCs) to the treated tumor and cause refractory tumor growth. The purposes of the studies were to determine whether whole body irradiation (WBIR) or a CXCR4 antagonist (AMD3100) will potentiate the effect of vatalanib (a VEGFR2 tyrosine kinase inhibitor) and prevent the refractory growth of GBM. Human GBM were grown orthotopically in three groups of rats (control, pretreated with WBIR and AMD3100) and randomly selected for vehicle or vatalanib treatments for 2 weeks. Then all animals underwent Magnetic Resonance Imaging (MRI) followed by euthanasia and histochemical analysis. Tumor volume and different vascular parameters (plasma volume (vp), forward transfer constant (Ktrans), back flow constant (kep), extravascular extracellular space volume (ve) were determined from MRI. In control group, vatalanib treatment increased the tumor growth significantly compared to that of vehicle treatment but by preventing the mobilization of BMDCs and interaction of CXCR4-SDF-1 using WBIR and ADM3100, respectively, paradoxical growth of tumor was controlled. Pretreatment with WBIR or AMD3100 also decreased tumor cell migration, despite the fact that ADM3100 increased the accumulation of M1 and M2 macrophages in the tumors. Vatalanib also increased Ktrans and ve in control animals but both of the vascular parameters were decreased when the animals were pretreated with WBIR and AMD3100. In conclusion, depleting bone marrow cells or CXCR4 interaction can potentiate the effect of vatalanib.
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Rai DP, Shankar A, Sandeep S, Ghimire MP, Khenata R, Thapa RK. Correction: Study of the enhanced electronic and thermoelectric (TE) properties of ZrxHf1−x−yTayNiSn: a first principles study. RSC Adv 2016. [DOI: 10.1039/c6ra90008a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Correction for ‘Study of the enhanced electronic and thermoelectric (TE) properties of ZrxHf1−x−yTayNiSn: a first principles study’ by D. P. Rai et al., RSC Adv., 2015, 5, 95353–95359.
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Poisson LM, Suhail H, Singh J, Datta I, Denic A, Labuzek K, Hoda MN, Shankar A, Kumar A, Cerghet M, Elias S, Mohney RP, Rodriguez M, Rattan R, Mangalam AK, Giri S. Untargeted Plasma Metabolomics Identifies Endogenous Metabolite with Drug-like Properties in Chronic Animal Model of Multiple Sclerosis. J Biol Chem 2015; 290:30697-712. [PMID: 26546682 DOI: 10.1074/jbc.m115.679068] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Indexed: 12/20/2022] Open
Abstract
We performed untargeted metabolomics in plasma of B6 mice with experimental autoimmune encephalitis (EAE) at the chronic phase of the disease in search of an altered metabolic pathway(s). Of 324 metabolites measured, 100 metabolites that mapped to various pathways (mainly lipids) linked to mitochondrial function, inflammation, and membrane stability were observed to be significantly altered between EAE and control (p < 0.05, false discovery rate <0.10). Bioinformatics analysis revealed six metabolic pathways being impacted and altered in EAE, including α-linolenic acid and linoleic acid metabolism (PUFA). The metabolites of PUFAs, including ω-3 and ω-6 fatty acids, are commonly decreased in mouse models of multiple sclerosis (MS) and in patients with MS. Daily oral administration of resolvin D1, a downstream metabolite of ω-3, decreased disease progression by suppressing autoreactive T cells and inducing an M2 phenotype of monocytes/macrophages and resident brain microglial cells. This study provides a proof of principle for the application of metabolomics to identify an endogenous metabolite(s) possessing drug-like properties, which is assessed for therapy in preclinical mouse models of MS.
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Tansey RJ, Benjamin-Laing H, Jassim S, Liekens K, Shankar A, Haddad FS. Successful return to high-level sports following early surgical repair of combined adductor complex and rectus abdominis avulsion. Bone Joint J 2015; 97-B:1488-92. [DOI: 10.1302/0301-620x.97b11.32924] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Hip and groin injuries are common in athletes who take part in high level sports. Adductor muscle tendon injuries represent a small but important number of these injuries. Avulsion of the tendons attached to the symphysis pubis has previously been described: these can be managed both operatively and non-operatively. We describe an uncommon variant of this injury, namely complete avulsion of the adductor sleeve complex: this includes adductor longus, pectineus and rectus abdominis. We go on to describe a surgical technique which promotes a full return to the pre-injury level of sporting activity. Over a period of ten years, 15 high-level athletes with an MRI-confirmed acute adductor complex avulsion injury (six to 34 days old) underwent surgical repair. The operative procedure consisted of anatomical re-attachment of the avulsed tissues in each case and mesh reinforcement of the posterior inguinal wall in seven patients. All underwent a standardised rehabilitation programme, which was then individualised to be sport-specific. One patient developed a superficial wound infection, which was successfully treated with antibiotics. Of the 15 patients, four complained of transient local numbness which resolved in all cases. All patients (including seven elite athletes) returned to their previous level of participation in sport. Cite this article: Bone Joint J 2015;97-B:1488–92.
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Novitsky Y, Fayezizadeh M, Majumder A, Yee S, Petro C, Orenstein S, Woeste G, Reinisch A, Bechstein WO, Rosen M, Carbonell A, Cobb W, Bauer J, Selzer D, Chao J, Harmaty M, Poulose B, Matthews B, Goldblatt M, Jacobsen G, Rosman C, Hansson B, Prabhu A, Fathi A, Skipworth J, Younis I, Floyd D, Shankar A, Olmi S, Cesana G, Ciccarese F, Uccelli M, Carrieri D, Castello G, Legnani G, Lyo V, Irwin C, Xu X, Harris H, Zuvela M, Galun D, Petrovic J, Palibrk I, Koncar I, Basaric D, Tian W, Fei Y, Pittman M, Jones E, Schwartz J, Mikami D, Perrakis A, Knüttel D, Klein P, Croner RS, Hohenberger W, Perrakis E, Müller V, Grande M, Villa M, Lisi G, Esser A, De Sanctis F, Petrella G, Birolini C, Miranda JS, Tanaka EY, Utiyama EM, Rasslan S, Shi Y, Guo XB, Zhuo HQ, Li LP, Liu HJ, Bauder A, Gerety P, Epps G, Pannucci C, Fischer J, Kovach S. Incisional Hernia: Difficult Cases 2. Hernia 2015; 19 Suppl 1:S105-11. [PMID: 26518784 DOI: 10.1007/bf03355335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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