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Murrell GA, Maddali S, Horovitz L, Oakley SP, Warren RF. The effects of time course after anterior cruciate ligament injury in correlation with meniscal and cartilage loss. Am J Sports Med 2001; 29:9-14. [PMID: 11206263 DOI: 10.1177/03635465010290012001] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In this study, 130 consecutive patients with anterior cruciate ligament insufficiency who were undergoing ligament reconstruction underwent arthroscopic examination at the time of reconstruction, and any loss of meniscal or chondral integrity was documented in a systematic fashion. In these patients, a greater proportion of the medial meniscus was lost compared with the lateral meniscus (16% versus 5%). On average, 6 cm2 of the articular cartilage was damaged (5.2 cm2) or lost (0.8 cm2), with the area of damage and loss greatest on the medial femoral condyle. Patients whose injuries had occurred more than 2 years before the examination had more than sixfold greater cartilage loss and damage compared with those whose injuries had occurred within the past 2 months. Meniscal loss was associated with a threefold increase in cartilage damage or loss. The group of patients with meniscal loss whose initial anterior cruciate ligament injury occurred more than 2 years before examination exhibited 18 times the amount of cartilage loss or damage as did the group that had no meniscal loss and whose injury occurred less than 1 month before examination.
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Mestre JR, Rivadeneira DE, Mackrell PJ, Duff M, Stapleton PP, Mack-Strong V, Maddali S, Smyth GP, Tanabe T, Daly JM. Overlapping CRE and E-box promoter elements can independently regulate COX-2 gene transcription in macrophages. FEBS Lett 2001; 496:147-51. [PMID: 11356200 DOI: 10.1016/s0014-5793(01)02422-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Macrophage cyclooxygenase-2 (COX-2) transcription is mediated through the collaboration of different promoter elements. Here, the role of an overlapping cyclic AMP responsive element (CRE)/E-box was investigated. Nuclear proteins bound both the CRE and E-box, which synergized with other promoter elements to induce COX-2 transcription. Endotoxin induced binding of nuclear proteins to the CRE and E-box and each element independently induced higher COX-2 transcription levels than the overlapping CRE/E-box. Transcription factors associated with the CRE binding complex included c-Jun and CRE binding protein and with the E-box binding complex USF-1; their overexpression significantly induced COX-2 transcription. Therefore, both CRE and E-box promoter elements regulate COX-2 transcription in macrophages.
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Maddali S, Calvo-Almazan I, Almer J, Kenesei P, Park JS, Harder R, Nashed Y, Hruszkewycz SO. Sparse recovery of undersampled intensity patterns for coherent diffraction imaging at high X-ray energies. Sci Rep 2018; 8:4959. [PMID: 29563508 PMCID: PMC5862902 DOI: 10.1038/s41598-018-23040-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 03/05/2018] [Indexed: 11/09/2022] Open
Abstract
Coherent X-ray photons with energies higher than 50 keV offer new possibilities for imaging nanoscale lattice distortions in bulk crystalline materials using Bragg peak phase retrieval methods. However, the compression of reciprocal space at high energies typically results in poorly resolved fringes on an area detector, rendering the diffraction data unsuitable for the three-dimensional reconstruction of compact crystals. To address this problem, we propose a method by which to recover fine fringe detail in the scattered intensity. This recovery is achieved in two steps: multiple undersampled measurements are made by in-plane sub-pixel motion of the area detector, then this data set is passed to a sparsity-based numerical solver that recovers fringe detail suitable for standard Bragg coherent diffraction imaging (BCDI) reconstruction methods of compact single crystals. The key insight of this paper is that sparsity in a BCDI data set can be enforced by recognising that the signal in the detector, though poorly resolved, is band-limited. This requires fewer in-plane detector translations for complete signal recovery, while adhering to information theory limits. We use simulated BCDI data sets to demonstrate the approach, outline our sparse recovery strategy, and comment on future opportunities.
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Kandel S, Maddali S, Allain M, Hruszkewycz SO, Jacobsen C, Nashed YSG. Using automatic differentiation as a general framework for ptychographic reconstruction. OPTICS EXPRESS 2019; 27:18653-18672. [PMID: 31252805 PMCID: PMC6825598 DOI: 10.1364/oe.27.018653] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Coherent diffraction imaging methods enable imaging beyond lens-imposed resolution limits. In these methods, the object can be recovered by minimizing an error metric that quantifies the difference between diffraction patterns as observed, and those calculated from a present guess of the object. Efficient minimization methods require analytical calculation of the derivatives of the error metric, which is not always straightforward. This limits our ability to explore variations of basic imaging approaches. In this paper, we propose to substitute analytical derivative expressions with the automatic differentiation method, whereby we can achieve object reconstruction by specifying only the physics-based experimental forward model. We demonstrate the generality of the proposed method through straightforward object reconstruction for a variety of complex ptychographic experimental models.
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Maddali S, Rodeo SA, Barnes R, Warren RF, Murrell GA. Postexercise increase in nitric oxide in football players with muscle cramps. Am J Sports Med 1998; 26:820-4. [PMID: 9850785 DOI: 10.1177/03635465980260061401] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Nitric oxide, a free radical inter- and intracellular messenger molecule, is important in exercise physiology. This study tested the hypothesis that serum nitric oxide concentrations change after strenuous exercise with severe generalized muscle cramps. The study group consisted of 77 professional football players in preseason training. All players' concentrations of serum nitrite and of other serum chemicals were determined during their preseason evaluations and compared with the concentrations in 40 serum samples taken from 25 of those same players who required intravenous rehydration for severe generalized muscle cramps after a training session. Player weight and percentage of body fat were significantly higher in players who received intravenous fluids than in players who did not. The serum of players requiring intravenous hydration showed evidence of skeletal muscle breakdown (increases in lactate dehydrogenase, creatinine phosphokinase, aspartate aminotransferase, and alanine aminotransferase) and of dehydration (elevations in protein, blood urea nitrogen, and cholesterol). The major finding, however, was a nearly 300% increase in serum nitrite concentrations in players requiring rehydration. There were no correlations between concentrations of nitrate and of any of the other serum chemicals. These data support the hypothesis that large amounts of nitric oxide are synthesized in professional football players after strenuous exercise with severe muscle cramps. The study design did not allow us to determine whether this increase in nitric oxide was due to exercise or muscle cramps or both, but it does provide a basis for evaluating these relationships.
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Strong VE, Winter J, Yan Z, Smyth GP, Mestre JR, Maddali S, Schaefer PA, Yurt RW, Stapleton PP, Daly JM. Prostaglandin E2 receptors EP2 and EP4 are down-regulated in human mononuclear cells after injury. Surgery 2001; 130:249-55. [PMID: 11490357 DOI: 10.1067/msy.2001.115901] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Recent characterization of prostaglandin receptor subtypes shows that each is critical to cellular functions and operates through separate signaling pathways that may explain differing effects of prostanoids. This study aimed to determine whether prostaglandin receptors EP2 and EP4 are modulated after injury and to evaluate the effect of prostaglandin E(2) (PGE(2)) addition and blockade on EP receptor expression. METHODS Peripheral blood mononuclear cells (PBMCs) isolated from 10 patients sustaining fracture or burn injury and 10 control subjects were stimulated with lipopolysaccharide +/- NS-398, an inhibitor of PGE(2) production. Samples were evaluated for production of PGE(2), tumor necrosis factor--alpha, and leukotriene B(4) as well as mRNA expression of EP receptors and COX-2. EP receptor expression was also evaluated after treating control PBMCs with PGE(2). RESULTS PBMCs from injured patients exhibited significant increases in PGE(2) production and COX-2 mRNA compared with control subjects, and these increases were inhibited by NS-398. In contrast, EP2 and EP4 receptors were markedly down-regulated after injury and NS-398 restored expression to control levels. Decreased EP2 and EP4 receptor expression after injury was replicated by coincubation of PBMCs with PGE(2). CONCLUSIONS Specific PGE(2) receptors are down-regulated after injury and NS-398 reverses this response. Furthermore, PGE(2) mediates EP2 and EP4 down-regulation. These data suggest that specific EP receptor subtypes may provide critical targets for augmenting the immune response after injury in humans.
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MESH Headings
- Adult
- Aged
- Burns/immunology
- Burns/metabolism
- Cyclooxygenase 2
- Cyclooxygenase 2 Inhibitors
- Cyclooxygenase Inhibitors/pharmacology
- Dinoprostone/analysis
- Dinoprostone/biosynthesis
- Down-Regulation/drug effects
- Down-Regulation/immunology
- Female
- Fractures, Bone/immunology
- Fractures, Bone/metabolism
- Gene Expression/drug effects
- Gene Expression/immunology
- Humans
- In Vitro Techniques
- Isoenzymes/genetics
- Leukocytes, Mononuclear/immunology
- Leukocytes, Mononuclear/metabolism
- Leukotriene B4/analysis
- Leukotriene B4/biosynthesis
- Lipopolysaccharide Receptors/genetics
- Lipopolysaccharides/pharmacology
- Male
- Membrane Proteins
- Middle Aged
- Nitrobenzenes/pharmacology
- Prostaglandin-Endoperoxide Synthases/genetics
- RNA, Messenger/analysis
- Receptors, Prostaglandin E/genetics
- Receptors, Prostaglandin E/immunology
- Receptors, Prostaglandin E/metabolism
- Receptors, Prostaglandin E, EP2 Subtype
- Receptors, Prostaglandin E, EP4 Subtype
- Signal Transduction/immunology
- Sulfonamides/pharmacology
- Tumor Necrosis Factor-alpha/analysis
- Tumor Necrosis Factor-alpha/biosynthesis
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Darooei M, Khan F, Rehan M, Zubeda S, Jeyashanker E, Annapurna S, Shah A, Maddali S, Hasan Q. MED12 somatic mutations encompassing exon 2 associated with benign breast fibroadenomas and not breast carcinoma in Indian women. J Cell Biochem 2018; 120:182-191. [DOI: 10.1002/jcb.27293] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 06/26/2018] [Indexed: 12/17/2022]
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Maddali S, Li P, Pateras A, Timbie D, Delegan N, Crook AL, Lee H, Calvo-Almazan I, Sheyfer D, Cha W, Heremans FJ, Awschalom DD, Chamard V, Allain M, Hruszkewycz SO. General approaches for shear-correcting coordinate transformations in Bragg coherent diffraction imaging. Part I. J Appl Crystallogr 2020. [DOI: 10.1107/s1600576720001363] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
This two-part article series provides a generalized description of the scattering geometry of Bragg coherent diffraction imaging (BCDI) experiments, the shear distortion effects inherent in the 3D image obtained from presently used methods and strategies to mitigate this distortion. Part I starts from fundamental considerations to present the general real-space coordinate transformation required to correct this shear, in a compact operator formulation that easily lends itself to implementation with available software packages. Such a transformation, applied as a final post-processing step following phase retrieval, is crucial for arriving at an undistorted, correctly oriented and physically meaningful image of the 3D crystalline scatterer. As the relevance of BCDI grows in the field of materials characterization, the available sparse literature that addresses the geometric theory of BCDI and the subsequent analysis methods are generalized here. This geometrical aspect, specific to coherent Bragg diffraction and absent in 2D transmission CDI experiments, gains particular importance when it comes to spatially resolved characterization of 3D crystalline materials in a reliable nondestructive manner. This series of articles describes this theory, from the diffraction in Bragg geometry to the corrections needed to obtain a properly rendered digital image of the 3D scatterer. Part I of this series provides the experimental BCDI community with the general form of the 3D real-space distortions in the phase-retrieved object, along with the necessary post-retrieval correction method. Part II builds upon the geometric theory developed in Part I with the formalism to correct the shear distortions directly on an orthogonal grid within the phase-retrieval algorithm itself, allowing more physically realistic constraints to be applied. Taken together, Parts I and II provide the X-ray science community with a set of generalized BCDI shear-correction techniques crucial to the final rendering of a 3D crystalline scatterer and for the development of new BCDI methods and experiments.
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Li P, Maddali S, Pateras A, Calvo-Almazan I, Hruszkewycz S, Cha W, Chamard V, Allain M. General approaches for shear-correcting coordinate transformations in Bragg coherent diffraction imaging. Part II. J Appl Crystallogr 2020. [DOI: 10.1107/s1600576720001375] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
X-ray Bragg coherent diffraction imaging (BCDI) has been demonstrated as a powerful 3D microscopy approach for the investigation of sub-micrometre-scale crystalline particles. The approach is based on the measurement of a series of coherent Bragg diffraction intensity patterns that are numerically inverted to retrieve an image of the spatial distribution of the relative phase and amplitude of the Bragg structure factor of the diffracting sample. This 3D information, which is collected through an angular rotation of the sample, is necessarily obtained in a non-orthogonal frame in Fourier space that must be eventually reconciled. To deal with this, the approach currently favored by practitioners (detailed in Part I) is to perform the entire inversion in conjugate non-orthogonal real- and Fourier-space frames, and to transform the 3D sample image into an orthogonal frame as a post-processing step for result analysis. In this article, which is a direct follow-up of Part I, two different transformation strategies are demonstrated, which enable the entire inversion procedure of the measured data set to be performed in an orthogonal frame. The new approaches described here build mathematical and numerical frameworks that apply to the cases of evenly and non-evenly sampled data along the direction of sample rotation (i.e. the rocking curve). The value of these methods is that they rely on the experimental geometry, and they incorporate significantly more information about that geometry into the design of the phase-retrieval Fourier transformation than the strategy presented in Part I. Two important outcomes are (1) that the resulting sample image is correctly interpreted in a shear-free frame and (2) physically realistic constraints of BCDI phase retrieval that are difficult to implement with current methods are easily incorporated. Computing scripts are also given to aid readers in the implementation of the proposed formalisms.
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Darooei M, Poornima S, Salma BU, Iyer GR, Pujar AN, Annapurna S, Shah A, Maddali S, Hasan Q. Pedigree and BRCA gene analysis in breast cancer patients to identify hereditary breast and ovarian cancer syndrome to prevent morbidity and mortality of disease in Indian population. Tumour Biol 2017; 39:1010428317694303. [PMID: 28231738 DOI: 10.1177/1010428317694303] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Global burden of breast cancer is expected to increase to >2 million new cases every year by 2030 and 10% of these are likely to have hereditary breast and ovarian cancer syndrome. Identifying these individuals by pedigree and BRCA1/2 mutation analyses will enable us to offer targeted mutation testing and appropriate counseling. This study from a tertiary care hospital showed that of the 127 breast cancer patients on treatment during 2014-2015, 24 of them fulfilled the criteria of hereditary breast and ovarian cancer syndrome after detailed verbal autopsy and pedigree analysis, and BRCA1 and 2 next-generation sequencing done after pre-test counseling revealed mutations in 13 cases (54%), these included 9 BRCA1 mutations (69%) and 4 BRCA2 mutation (31%). Subsequent post-test counseling recommended targeted mutation analysis for 64 high-risk members in these 13 families with pathogenic mutations, which will help in surveillance for early detection, appropriate management, and prevention of the disease by decreasing the burden to both family and nation. Results from this preliminary study highlight the importance of genetic counseling, pedigree analysis, and genetic testing. It can be recommended that all oncology units should have a genetic counseling service for providing appropriate support to oncologists, patients, and families to prevent unnecessary testing; however, breast cancer screening program is incomplete without evaluating for hereditary breast and ovarian cancer syndrome.
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Ulvestad A, Hruszkewycz SO, Holt MV, Hill MO, Calvo-Almazán I, Maddali S, Huang X, Yan H, Nazaretski E, Chu YS, Lauhon LJ, Rodkey N, Bertoni MI, Stuckelberger ME. Multimodal X-ray imaging of grain-level properties and performance in a polycrystalline solar cell. JOURNAL OF SYNCHROTRON RADIATION 2019; 26:1316-1321. [PMID: 31274460 PMCID: PMC6613129 DOI: 10.1107/s1600577519003606] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 02/14/2019] [Indexed: 06/09/2023]
Abstract
The factors limiting the performance of alternative polycrystalline solar cells as compared with their single-crystal counterparts are not fully understood, but are thought to originate from structural and chemical heterogeneities at various length scales. Here, it is demonstrated that multimodal focused nanobeam X-ray microscopy can be used to reveal multiple aspects of the problem in a single measurement by mapping chemical makeup, lattice structure and charge collection efficiency simultaneously in a working solar cell. This approach was applied to micrometre-sized individual grains in a Cu(In,Ga)Se2 polycrystalline film packaged in a working device. It was found that, near grain boundaries, collection efficiency is increased, and that in these regions the lattice parameter of the material is expanded. These observations are discussed in terms of possible physical models and future experiments.
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Erukkambattu J, Prabhala S, Miryala S, Maddali S, Tanikella R. Occult B-Cell Lymphoma Associated With Hemophagocytic Syndrome: A Case Report. J Hematol 2014. [DOI: 10.14740/jh176w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Duff M, Smyth GP, Mestre JR, Yan ZP, Cruz V, Maddali S, Matsuda T, Stapleton PP, Daly JM. Cyclo-oxygenase inhibitor and interferon-γ act synergistically to reduce melanoma growth and improve survival in a murine model. Ir J Med Sci 2002. [DOI: 10.1007/bf03170085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Murrell GAC, Maddali S, Rodeo SA, Barnes R, Warren RF. Muscle cramps in American Football players. J Sci Med Sport 1999. [DOI: 10.1016/s1440-2440(99)80151-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Maddali LS, Maddali S. Pattern of malignancies in geriatric patients. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.19650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
19650 Background: Information regarding pattern of malignancies in geriatric patients in India is not readily available. Methods: Between 1st January 1999 and 31st December 2006 we encountered 832 geriatric patients among a total of 3748 cases. Analysis was done with respect to age, sex and disease. Results: Geriatric patients constituted 832/3748 (22.20%) of our work load. Males 432 (51.92%) Females 400 (48.08%). Hematologic malignancies 214 (25.72%) Solid tumors 618 (74.28%). male preponderance in Hematologic malignancies 141/214 (66.89%); female preponderance in solid tumors 327/618 (52.91%). Top 7 malignancies: Males (432)-NSCLC 60 (13.89%) Prostate 57 (13.19%) NHL 48 (11.11%) Myeloma 39 (9.03%) CLL 31 (7.18%) HNSCC 30 (6.94%) Colon 26 (6.02%); Females (400)- Breast 147 (36.75%) Ovary 50 (12.50%) Uterus 44 (11.00%) NHL 25 (6.25%) Colon 20 (5.00%) NSCLC 11 (2.75%) CML 10 (2.50%). Age groups: (65–70) yrs-517 (62.13%) males 254, females 263; (71–80) yrs-264 (31.73%) males 152 females 112; (81–90) yrs-48 (5.78%) males 24, females 24; >91yrs-3 (0.36%) males 2 female 1. Top 5 malignancies in each age & sex group: Males, (65–70) yrs, 254: NSCLC 39 NHL 30 Prostate 29 Myeloma 24 Colon 19; (71–80) yrs, 152: Prostate 20 NSCLC 19 NHL 17 CLL 15 HNSCC 14; (81–90) yrs, 24: Prostate 7 Myeloma 2 CLL 2 CML 2 AML 2; Females, (65–70) yrs, 263: Breast 99 Ovary 37 Uterus 30 colon 13 NHL 13; (71–80) yrs, 112: Breast 41 Ovary 12 NHL 11 Uterus 10 CLL 9; (81–90) yrs, 24: Breast 7 Uterus 4 CLL 2 Renal cell carcinoma 2 Ovary 1. Conclusions: Solid tumors are the predominant malignancies in geriatric patients 618/832 (74.28%). B Cell neoplasms constitute bulk of the hematologic neoplasms 173/214 (80.84%). Sarcomas are uncommon 20/832 (2.40%). Important solid tumors: Prostate, NSCLC, Colon and HNSCC in males; Breast, Ovary, Uterus and colon in females. Age group (65–70) yrs is the major group 517/832 (62.13%) followed by significant age group (71–80) yrs 264/832 (31.73%). It is imperative to employ curative strategies for malignancies in this ever expanding population. No significant financial relationships to disclose.
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Kandel S, Maddali S, Nashed YSG, Hruszkewycz SO, Jacobsen C, Allain M. Efficient ptychographic phase retrieval via a matrix-free Levenberg-Marquardt algorithm. OPTICS EXPRESS 2021; 29:23019-23055. [PMID: 34614577 PMCID: PMC8327924 DOI: 10.1364/oe.422768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 06/04/2021] [Accepted: 06/04/2021] [Indexed: 06/13/2023]
Abstract
The phase retrieval problem, where one aims to recover a complex-valued image from far-field intensity measurements, is a classic problem encountered in a range of imaging applications. Modern phase retrieval approaches usually rely on gradient descent methods in a nonlinear minimization framework. Calculating closed-form gradients for use in these methods is tedious work, and formulating second order derivatives is even more laborious. Additionally, second order techniques often require the storage and inversion of large matrices of partial derivatives, with memory requirements that can be prohibitive for data-rich imaging modalities. We use a reverse-mode automatic differentiation (AD) framework to implement an efficient matrix-free version of the Levenberg-Marquardt (LM) algorithm, a longstanding method that finds popular use in nonlinear least-square minimization problems but which has seen little use in phase retrieval. Furthermore, we extend the basic LM algorithm so that it can be applied for more general constrained optimization problems (including phase retrieval problems) beyond just the least-square applications. Since we use AD, we only need to specify the physics-based forward model for a specific imaging application; the first and second-order derivative terms are calculated automatically through matrix-vector products, without explicitly forming the large Jacobian or Gauss-Newton matrices typically required for the LM method. We demonstrate that this algorithm can be used to solve both the unconstrained ptychographic object retrieval problem and the constrained "blind" ptychographic object and probe retrieval problems, under the popular Gaussian noise model as well as the Poisson noise model. We compare this algorithm to state-of-the-art first order ptychographic reconstruction methods to demonstrate empirically that this method outperforms best-in-class first-order methods: it provides excellent convergence guarantees with (in many cases) a superlinear rate of convergence, all with a computational cost comparable to, or lower than, the tested first-order algorithms.
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Maddali LS, Maddali S. Multiple primary neoplasms involving the breast. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.10786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
10786 Background: Multiple Primary Neoplasms (MPN) are being identified with increasing frequency in Breast cancer patients. We studied MPN involving Breast cancer as at least one primary for (1) incidence and (2) identifying. subsets with special features. Methods: 83 patients with MPN were identified among 3378 patients seen between January 1st 1999 and 31st December 2005. (2.15%). 40 of these had Breast primary (48.19%). which form the basis of the present report. One or both primaries were identified during this period. But in some cases with primaries in remote past, available documentation was accepted. Results: Breast cancer was the Index cancer 31/40 (77.50%)and second primary in 9/40 (22.50%). Among the index cancers, 4/31 cases (12.90%) were synchronous and 27/31 (87.10%) were metachronous. 100% of the second primary in breast group were metachronous. Breast-Breast MPN 15/40 (37.50%) and Breast-Non breast MPN 25/40 (62.50%). Mean ages for Breast-Breast MPN 47.33 years, Synchronous tumors 38.66 yrs, metachronous tumors 58.20 yrs, Breast-Non Breast MPN 55.44 yrs. Mortality for Breast-Breast MPN as a group was 73.33%, synchronous tumors (2/3) 66.67%, metachronous tumors (10/12) 83.33%, Breast-Non Breast MPN, metachronous tumors (13/24) 54.17%. When the interval between index and second primary was studied, the Breast-Breast MPN mortality was (7/9) 77.78% for 2 yrs or less duration, (3/3) 100% for more than 2yrs. For Breast-NonBreast MPN, mortality was (6/9) 66.67% for duration of 2 yrs or less and (7/15) 46.67% for more than 2 yrs. The common malignancies associated in the index Breast cancer group were from Ovary (6),Thyroid (2),pancreas (2), Hematologic neoplasms (3) Upper Aero Digestive Tract (2). The second primary Breast cancer group had primaries in ovary (2), colon (2), hematologic (3) neoplasms. Conclusions: Breast-Breast MPN are seen in younger patients with higher mortality than Breast-Non Breast MPN. In the Breast-Non Breast MPN group, longer interval between the primaries is associated with lower mortality. There were no major differences between the Index Breast cancer group and Breast Second Primary group. Mortality appeared to be determined by the nature of the Non Breast Primary. No significant financial relationships to disclose.
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Murrell GAC, Maddali S, Horovitz L, Warren RF. The effects of time since injury and meniscal loss on cartilage integrity in anterior cruciate ligament insufficient knees. J Sci Med Sport 1999. [DOI: 10.1016/s1440-2440(99)80164-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Bertaux N, Allain M, Weizeorick J, Park JS, Kenesei P, Shastri SD, Almer J, Highland MJ, Maddali S, Hruszkewycz SO. Sub-pixel high-resolution imaging of high-energy x-rays inspired by sub-wavelength optical imaging. OPTICS EXPRESS 2021; 29:35003-35021. [PMID: 34808946 DOI: 10.1364/oe.438945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 09/06/2021] [Indexed: 06/13/2023]
Abstract
We have developed and demonstrated an image super-resolution method-XR-UNLOC: X-Ray UNsupervised particle LOCalization-for hard x-rays measured with fast-frame-rate detectors that is an adaptation of the principle of photo-activated localization microscopy (PALM) and stochastic optical reconstruction microscopy (STORM), which enabled biological fluorescence imaging at sub-optical-wavelength scales. We demonstrate the approach on experimental coherent Bragg diffraction data measured with 52 keV x-rays from a nanocrystalline sample. From this sample, we resolve the fine fringe detail of a high-energy x-ray Bragg coherent diffraction pattern to an upsampling factor of 16 of the native pixel pitch of 30 μm of a charge-integrating fastCCD detector. This was accomplished by analysis of individual photon locations in a series of "nearly-dark" instances of the diffraction pattern that each contain only a handful of photons. Central to our approach was the adaptation of the UNLOC photon fitting routine for PALM/STORM to the hard x-ray regime to handle much smaller point spread functions, which required a different statistical test for photon detection and for sub-pixel localization. A comparison to a photon-localization strategy used in the x-ray community ("droplet analysis") showed that XR-UNLOC provides significant improvement in super-resolution. We also developed a metric by which to estimate the limit of reliable upsampling with XR-UNLOC under a given set of experimental conditions in terms of the signal-to-noise ratio of a photon detection event and the size of the point spread function for guiding future x-ray experiments in many disciplines where detector pixelation limits must be overcome.
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Maddali LS, Maddali S. Multiple primary cancers involving nonbreast sites. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.e12033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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