Data Access Based on a Guide Map of the Underwater Wireless Sensor Network.

PubMed

Wei, Zhengxian; Song, Min; Yin, Guisheng; Song, Houbing; Wang, Hongbin; Ma, Xuefei; Cheng, Albert M K

2017-10-17

Underwater wireless sensor networks (UWSNs) represent an area of increasing research interest, as data storage, discovery, and query of UWSNs are always challenging issues. In this paper, a data access based on a guide map (DAGM) method is proposed for UWSNs. In DAGM, the metadata describes the abstracts of data content and the storage location. The center ring is composed of nodes according to the shortest average data query path in the network in order to store the metadata, and the data guide map organizes, diffuses and synchronizes the metadata in the center ring, providing the most time-saving and energy-efficient data query service for the user. For this method, firstly the data is stored in the UWSN. The storage node is determined, the data is transmitted from the sensor node (data generation source) to the storage node, and the metadata is generated for it. Then, the metadata is sent to the center ring node that is the nearest to the storage node and the data guide map organizes the metadata, diffusing and synchronizing it to the other center ring nodes. Finally, when there is query data in any user node, the data guide map will select a center ring node nearest to the user to process the query sentence, and based on the shortest transmission delay and lowest energy consumption, data transmission routing is generated according to the storage location abstract in the metadata. Hence, specific application data transmission from the storage node to the user is completed. The simulation results demonstrate that DAGM has advantages with respect to data access time and network energy consumption.

Automatic identification of IASLC-defined mediastinal lymph node stations on CT scans using multi-atlas organ segmentation

NASA Astrophysics Data System (ADS)

Hoffman, Joanne; Liu, Jiamin; Turkbey, Evrim; Kim, Lauren; Summers, Ronald M.

2015-03-01

Station-labeling of mediastinal lymph nodes is typically performed to identify the location of enlarged nodes for cancer staging. Stations are usually assigned in clinical radiology practice manually by qualitative visual assessment on CT scans, which is time consuming and highly variable. In this paper, we developed a method that automatically recognizes the lymph node stations in thoracic CT scans based on the anatomical organs in the mediastinum. First, the trachea, lungs, and spines are automatically segmented to locate the mediastinum region. Then, eight more anatomical organs are simultaneously identified by multi-atlas segmentation. Finally, with the segmentation of those anatomical organs, we convert the text definitions of the International Association for the Study of Lung Cancer (IASLC) lymph node map into patient-specific color-coded CT image maps. Thus, a lymph node station is automatically assigned to each lymph node. We applied this system to CT scans of 86 patients with 336 mediastinal lymph nodes measuring equal or greater than 10 mm. 84.8% of mediastinal lymph nodes were correctly mapped to their stations.

Simultaneous mapping of pan and sentinel lymph nodes for real-time image-guided surgery.

PubMed

Ashitate, Yoshitomo; Hyun, Hoon; Kim, Soon Hee; Lee, Jeong Heon; Henary, Maged; Frangioni, John V; Choi, Hak Soo

2014-01-01

The resection of regional lymph nodes in the basin of a primary tumor is of paramount importance in surgical oncology. Although sentinel lymph node mapping is now the standard of care in breast cancer and melanoma, over 20% of patients require a completion lymphadenectomy. Yet, there is currently no technology available that can image all lymph nodes in the body in real time, or assess both the sentinel node and all nodes simultaneously. In this study, we report an optical fluorescence technology that is capable of simultaneous mapping of pan lymph nodes (PLNs) and sentinel lymph nodes (SLNs) in the same subject. We developed near-infrared fluorophores, which have fluorescence emission maxima either at 700 nm or at 800 nm. One was injected intravenously for identification of all regional lymph nodes in a basin, and the other was injected locally for identification of the SLN. Using the dual-channel FLARE intraoperative imaging system, we could identify and resect all PLNs and SLNs simultaneously. The technology we describe enables simultaneous, real-time visualization of both PLNs and SLNs in the same subject.

A prospective investigation of fluorescence imaging to detect sentinel lymph nodes at robotic-assisted endometrial cancer staging.

PubMed

Paley, Pamela J; Veljovich, Dan S; Press, Joshua Z; Isacson, Christina; Pizer, Ellen; Shah, Chirag

2016-07-01

The accuracy of sentinel lymph node mapping has been shown in endometrial cancer, but studies to date have primarily focused on cohorts at low risk for nodal involvement. In our practice, we acknowledge the lack of benefit of lymphadenectomy in the low-risk subgroup and omit lymph node removal in these patients. Thus, our aim was to evaluate the feasibility and accuracy of sentinel node mapping in women at sufficient risk for nodal metastasis warranting lymphadenectomy and in whom the potential benefit of avoiding nodal procurement could be realized. To evaluate the detection rate and accuracy of fluorescence-guided sentinel lymph node mapping in endometrial cancer patients undergoing robotic-assisted staging. One hundred twenty-three endometrial cancer patients undergoing sentinel lymph node sentinel node mapping using indocyanine green were prospectively evaluated. Two mL (1.0 mg/mL) of dye were injected into the cervical stroma divided between the 2-3 and 9-10 o'clock positions at the time of uterine manipulator placement. Before hysterectomy, the retroperitoneal spaces were developed and fluorescence imaging was used for sentinel node detection. Identified sentinel nodes were removed and submitted for touch prep intraoperatively, followed by permanent assessment with routine hematoxylin and eosin levels. Patients then underwent hysterectomy, bilateral salpingo-oophorectomy, and completion bilateral pelvic and periaortic lymphadenectomy based on intrauterine risk factors determined intraoperatively (tumor size >2 cm, >50% myometrial invasion, and grade 3 histology). Of 123 patients enrolled, at least 1 sentinel node was detected in 119 (96.7%). Ninety-nine patients (80%) had bilateral pelvic or periaortic sentinel nodes detected. A total of 85 patients met criteria warranting completion lymphadenectomy. In 14 patients (16%) periaortic lymphadenectomy was not feasible, and the mean number of pelvic nodes procured was 13 (6-22). Of the 71 patients undergoing pelvic and periaortic lymphadenectomy, the mean nodal count was 23.2 (8-51). Of patients undergoing lymphadenectomy, 10.6% had lymph node metastasis on final hematoxylin and eosin evaluation. Notably, the sentinel node was the only positive node in 44% of cases. There were no cases in which final pathology of the sentinel node was negative and metastatic disease was detected upon completion lymphadenectomy in the non-sentinel nodes (no false negatives), yielding a sensitivity of 100%. Of the 14 sentinel nodes ultimately found to harbor metastases, 3 were negative on touch prep, yielding a sensitivity of 78.6% for intraoperative detection of sentinel node involvement. In all 3 of the false-negative touch preps, final pathology detected a single micrometastasis (0.24 mm, 1.4 mm, 1.5 mm). As expected, there were no false-positive results, yielding a specificity of 100%. No complications related to sentinel node mapping or allergic reactions to the dye were encountered. Intraoperative sentinel node mapping using fluorescence imaging with indocyanine green in endometrial cancer patients is feasible and yields high detection rates. In our pilot study, sentinel node mapping identified all women with Stage IIIC disease. Low false-negative rates are encouraging, and if confirmed in multi-institutional trials, this approach would be anticipated to reduce the morbidity, operative times, and costs associated with complete pelvic and periaortic lymphadenectomy. Copyright © 2015 Elsevier Inc. All rights reserved.

Sentinel lymph node biopsy in the management of early-stage cervical carcinoma.

PubMed

Diaz, John P; Gemignani, Mary L; Pandit-Taskar, Neeta; Park, Kay J; Murray, Melissa P; Chi, Dennis S; Sonoda, Yukio; Barakat, Richard R; Abu-Rustum, Nadeem R

2011-03-01

We aimed to determine the sentinel lymph node detection rates, accuracy in predicting the status of lymph node metastasis, and if pathologic ultrastaging improves the detection of micrometastases and isolated tumor cells at the time of primary surgery for cervical cancer. A prospective, non-randomized study of women with early-stage (FIGO stage IA1 with lymphovascular space involvement--IIA) cervical carcinoma was conducted from June 2003 to August 2009. All patients underwent an intraoperative intracervical blue dye injection. Patients who underwent a preoperative lymphoscintigraphy received a 99m Tc sulfur colloid injection in addition. All patients underwent sentinel lymph node (SLN) identification followed by a complete pelvic node and parametrial dissection. SLN were evaluated using our institutional protocol that included pathologic ultrastaging. SLN mapping was successful in 77 (95%) of 81 patients. A total of 316 SLN were identified, with a median of 3 SLN per patient (range, 0-10 SLN). The majority (85%) of SLN were located at three main sites: the external iliac (35%); internal iliac (30%); and obturator (20%). Positive lymph nodes (LN) were identified in 26 (32%) patients, including 21 patients with positive SLN. Fifteen of 21 patients (71%) had SLN metastasis detected on routine processing. SLN ultrastaging detected metastasis in an additional 6/21 patients (29%). Two patients had grossly positive LN at exploration, and mapping was abandoned. Three of 26 (12%) patients had successful SLN mapping; however, the SLN failed to identify the metastatic LN. Of these 3 false negative cases, 2 patients had a metastatic parametrial node as the only positive LN with multiple negative pelvic nodes including negative SLN. One patient with stage IA1 disease and lymphovascular invasion had unilateral SLN mapping and a metastatic common iliac LN identified on completion lymphadenectomy of the contralateral side that did not map. The 4 (5%) patients with unsuccessful mapping included 1 who had grossly positive nodes identified at the time of laparotomy; the remaining 3 occurred during each surgeon's initial SLN mapping learning phase. SLN mapping in early-stage cervical carcinoma yields high detection rates. Ultrastaging improves micrometastasis detection. Parametrectomy and side-specific lymphadenectomy (in cases of failed mapping) remain important components of the surgical management of selected cases. Copyright © 2010 Elsevier Inc. All rights reserved.

Contrast-enhanced ultrasound mapping of sentinel lymph nodes in oral tongue cancer-a pilot study.

PubMed

Gvetadze, Shalva R; Xiong, Ping; Lv, Mingming; Li, Jun; Hu, Jingzhou; Ilkaev, Konstantin D; Yang, Xin; Sun, Jian

2017-03-01

To assess the usefulness of contrast-enhanced ultrasound (CEUS) with peritumoral injection of microbubble contrast agent for detecting the sentinel lymph nodes for oral tongue carcinoma. The study was carried out on 12 patients with T1-2cN0 oral tongue cancer. A radical resection of the primary disease was planned; a modified radical supraomohyoid neck dissection was reserved for patients with larger lesions (T2, n = 8). The treatment plan and execution were not influenced by sentinel node mapping outcome. The Sonovue ™ contrast agent (Bracco Imaging, Milan, Italy) was utilized. After detection, the position and radiologic features of the sentinel nodes were recorded. The identification rate of the sentinel nodes was 91.7%; one patient failed to demonstrate any enhanced areas. A total of 15 sentinel nodes were found in the rest of the 11 cases, with a mean of 1.4 nodes for each patient. The sentinel nodes were localized in: Level IA-1 (6.7%) node; Level IB-11 (73.3%) nodes; Level IIA-3 (20.0%) nodes. No contrast-related adverse effects were observed. For oral tongue tumours, CEUS is a feasible and potentially widely available approach of sentinel node mapping. Further clinical research is required to establish the position of CEUS detection of the sentinel nodes in oral cavity cancers.

A critical assessment on the role of sentinel node mapping in endometrial cancer.

PubMed

Bogani, Giorgio; Ditto, Antonino; Martinelli, Fabio; Signorelli, Mauro; Perotto, Stefania; Lorusso, Domenica; Raspagliesi, Francesco

2015-10-01

Endometrial cancer is the most common gynecologic malignancy in the developed countries. Although the high incidence of this occurrence no consensus, about the role of retroperitoneal staging, still exists. Growing evidence support the safety and efficacy of sentinel lymph node mapping. This technique is emerging as a new standard for endometrial cancer staging procedures. In the present paper, we discuss the role of sentinel lymph node mapping in endometrial cancer, highlighting the most controversies features.

Absorption Reconstruction Improves Biodistribution Assessment of Fluorescent Nanoprobes Using Hybrid Fluorescence-mediated Tomography

PubMed Central

Gremse, Felix; Theek, Benjamin; Kunjachan, Sijumon; Lederle, Wiltrud; Pardo, Alessa; Barth, Stefan; Lammers, Twan; Naumann, Uwe; Kiessling, Fabian

2014-01-01

Aim: Fluorescence-mediated tomography (FMT) holds potential for accelerating diagnostic and theranostic drug development. However, for proper quantitative fluorescence reconstruction, knowledge on optical scattering and absorption, which are highly heterogeneous in different (mouse) tissues, is required. We here describe methods to assess these parameters using co-registered micro Computed Tomography (µCT) data and nonlinear whole-animal absorption reconstruction, and evaluate their importance for assessment of the biodistribution and target site accumulation of fluorophore-labeled drug delivery systems. Methods: Besides phantoms with varying degrees of absorption, mice bearing A431 tumors were imaged 15 min and 48 h after i.v. injection of a fluorophore-labeled polymeric drug carrier (pHPMA-Dy750) using µCT-FMT. The outer shape of mice and a scattering map were derived using automated segmentation of the µCT data. Furthermore, a 3D absorption map was reconstructed from the trans-illumination data. We determined the absorption of five interactively segmented regions (heart, liver, kidney, muscle, tumor). Since blood is the main near-infrared absorber in vivo, the absorption was also estimated from the relative blood volume (rBV), determined by contrast-enhanced µCT. We compared the reconstructed absorption with the rBV-based values and analyzed the effect of using the absorption map on the fluorescence reconstruction. Results: Phantom experiments demonstrated that absorption reconstruction is possible and necessary for quantitative fluorescence reconstruction. In vivo, the reconstructed absorption showed high values in strongly blood-perfused organs such as the heart, liver and kidney. The absorption values correlated strongly with the rBV-based absorption values, confirming the accuracy of the absorption reconstruction. Usage of homogenous absorption instead of the reconstructed absorption map resulted in reduced values in the heart, liver and kidney, by factors of 3.5, 2.1 and 1.4, respectively. For muscle and subcutaneous tumors, which have a much lower rBV and absorption, absorption reconstruction was less important. Conclusion: Quantitative whole-animal absorption reconstruction is possible and can be validated in vivo using the rBV. Usage of an absorption map is important when quantitatively assessing the biodistribution of fluorescently labeled drugs and drug delivery systems, to avoid a systematic underestimation of fluorescence in strongly absorbing organs, such as the heart, liver and kidney. PMID:25157277

Multi Robot Path Planning for Budgeted Active Perception with Self-Organising Maps

DTIC Science & Technology

2016-10-04

Multi- Robot Path Planning for Budgeted Active Perception with Self-Organising Maps Graeme Best1, Jan Faigl2 and Robert Fitch1 Abstract— We propose a...optimise paths for a multi- robot team that aims to maximally observe a set of nodes in the environment. The selected nodes are observed by visiting...regions, each node has an observation reward, and the robots are constrained by travel budgets. The SOM algorithm jointly selects and allocates nodes

Lymphatic drainage in renal cell carcinoma: back to the basics.

PubMed

Karmali, Riaz J; Suami, Hiroo; Wood, Christopher G; Karam, Jose A

2014-12-01

Lymphatic drainage in renal cell carcinoma (RCC) is unpredictable, however, basic patterns can be observed in cadaveric and sentinel lymph node mapping studies in patients with RCC. The existence of peripheral lymphovenous communications at the level of the renal vein has been shown in mammals but remains unknown in humans. The sentinel lymph node biopsy technique can be safely applied to map lymphatic drainage patterns in patients with RCC. Further standardisation of sentinel node biopsy techniques is required to improve the clinical significance of mapping studies. Understanding lymphatic drainage in RCC may lead to an evidence-based consensus on the surgical management of retroperitoneal lymph nodes. © 2014 The Authors. BJU International © 2014 BJU International.

Consistency mapping of 16 lymph node stations in gastric cancer by CT-based vessel-guided delineation of 255 patients.

PubMed

Xu, Shuhang; Feng, Lingling; Chen, Yongming; Sun, Ying; Lu, Yao; Huang, Shaomin; Fu, Yang; Zheng, Rongqin; Zhang, Yujing; Zhang, Rong

2017-06-20

In order to refine the location and metastasis-risk density of 16 lymph node stations of gastric cancer for neoadjuvant radiotherapy, we retrospectively reviewed the initial images and pathological reports of 255 gastric cancer patients with lymphatic metastasis. Metastatic lymph nodes identified in the initial computed tomography images were investigated by two radiologists with gastrointestinal specialty. A circle with a diameter of 5 mm was used to identify the central position of each metastatic lymph node, defined as the LNc (the central position of the lymph node). The LNc was drawn at the equivalent location on the reference images of a standard patient based on the relative distances to the same reference vessels and the gastric wall using a Monaco® version 5.0 workstation. The image manipulation software Medi-capture was programmed for image analysis to produce a contour and density atlas of 16 lymph node stations. Based on a total of 2846 LNcs contoured (31-599 per lymph node station), we created a density distribution map of 16 lymph node drainage stations of the stomach on computed tomography images, showing the detailed radiographic delineation of each lymph node station as well as high-risk areas for lymph node metastasis. Our mapping can serve as a template for the delineation of gastric lymph node stations when defining clinical target volume in pre-operative radiotherapy for gastric cancer.

Lymphatic mapping with fluorescence navigation using indocyanine green and axillary surgery in patients with primary breast cancer.

PubMed

Takeuchi, Megumi; Sugie, Tomoharu; Abdelazeem, Kassim; Kato, Hironori; Shinkura, Nobuhiko; Takada, Masahiro; Yamashiro, Hiroyasu; Ueno, Takayuki; Toi, Masakazu

2012-01-01

The indocyanine green fluorescence (ICGf) navigation method provides real-time lymphatic mapping and sentinel lymph node (SLN) visualization, which enables the removal of SLNs and their associated lymphatic networks. In this study, we investigated the features of the drainage pathways detected with the ICGf navigation system and the order of metastasis in axillary nodes. From April 2008 to February 2010, 145 patients with clinically node-negative breast cancer underwent SLN surgery with ICGf navigation. The video-recorded data from 79 patients were used for lymphatic mapping analysis. We analyzed 145 patients with clinically node-negative breast cancer who underwent SLN surgery with the ICGf navigation system. Fluorescence-positive SLNs were identified in 144 (99%) of 145 patients. Both single and multiple routes to the axilla were identified in 47% of cases using video-recorded lymphatic mapping data. An internal mammary route was detected in 6% of the cases. Skip metastasis to the second or third SLNs was observed in 6 of the 28 node-positive patients. We also examined the strategy of axillary surgery using the ICGf navigation system. We found that, based on the features of nodal involvement, 4-node resection could provide precise information on the nodal status. The ICGf navigation system may provide a different lymphatic mapping result than computed tomography lymphography in clinically node-negative breast cancer patients. Furthermore, it enables the identification of lymph nodes that do not accumulate indocyanine green or dye adjacent to the SLNs in the sequence of drainage. Knowledge of the order of nodal metastasis as revealed by the ICGf system may help to personalize the surgical treatment of axilla in SLN-positive cases, although additional studies are required. © 2012 Wiley Periodicals, Inc.

Synthesis of a novel polyamidoamine dendrimer conjugating with alkali blue as a lymphatic tracer and study on the lymphatic targeting in vivo.

PubMed

Yang, Rui; Xia, Suxia; Ye, Tiantian; Yao, Jianhua; Zhang, Ruizhi; Wang, Shujun; Wang, Siling

2016-09-01

In this study, a novel lymphatic tracer polyamidoamin-alkali blue (PAMAM-AB) was synthesized in order to evaluate the intra-lymphatic targeting ability and lymphatic tropism of PAMAM-AB after subcutaneous administration. UV-Vis, FT-IR, NMR and HPLC characterization were performed to prove the successful synthesis of PAMAM-AB. The calculated AB payload of PAMAM-AB conjugate was seven per dendrimer molecule (27.16% by weight). Hydrolysis stability of PAMAM-AB in vitro was evaluated, which was stable in PBS and human plasma. Lymphatic tracing were studied to determine the blue-stained intensity of PAMAM-AB in right popliteral lymph nodes (PLNs), iliac lymph nodes (ILNs) and para-aortic lymph nodes (PALNs) after subcutaneous administration. The pharmacokinetics and biodistribution of PAMAM-AB in mice were investigated. PLNs, ILNs and PALNs could be obviously blue-stained within 10 min after PAMAM-AB administration, and displayed a more rapid lymphatic absorption, a higher AUC value in lymph nodes and a longer lymph nodes residence time compared with methylene blue solution (MB-S), MB water-in-oil microemulsion (MB-ME), MB multiple microemulsion (MB-MME). Enhanced lymphatic drainage from the injection site and uptake into lymph of PAMAM-AB indicated that PAMAM-AB possesses the double function of lymphatic tracing and lymphatic targeting, and suggested the potential for the development of lymphatic targeting vectors or as a lymphatic tracer in its own right.

Sentinel lymph node mapping in minimally invasive surgery: Role of imaging with color-segmented fluorescence (CSF).

PubMed

Lopez Labrousse, Maite I; Frumovitz, Michael; Guadalupe Patrono, M; Ramirez, Pedro T

2017-09-01

Sentinel lymph node mapping, alone or in combination with pelvic lymphadenectomy, is considered a standard approach in staging of patients with cervical or endometrial cancer [1-3]. The goal of this video is to demonstrate the use of indocyanine green (ICG) and color-segmented fluorescence when performing lymphatic mapping in patients with gynecologic malignancies. Injection of ICG is performed in two cervical sites using 1mL (0.5mL superficial and deep, respectively) at the 3 and 9 o'clock position. Sentinel lymph nodes are identified intraoperatively using the Pinpoint near-infrared imaging system (Novadaq, Ontario, CA). Color-segmented fluorescence is used to image different levels of ICG uptake demonstrating higher levels of perfusion. A color key on the side of the monitor shows the colors that coordinate with different levels of ICG uptake. Color-segmented fluorescence may help surgeons identify true sentinel nodes from fatty tissue that, although absorbing fluorescent dye, does not contain true nodal tissue. It is not intended to differentiate the primary sentinel node from secondary sentinel nodes. The key ranges from low levels of ICG uptake (gray) to the highest rate of ICG uptake (red). Bilateral sentinel lymph nodes are identified along the external iliac vessels using both standard and color-segmented fluorescence. No evidence of disease was noted after ultra-staging was performed in each of the sentinel nodes. Use of ICG in sentinel lymph node mapping allows for high bilateral detection rates. Color-segmented fluorescence may increase accuracy of sentinel lymph node identification over standard fluorescent imaging. The following are the supplementary data related to this article. Copyright © 2017 Elsevier Inc. All rights reserved.

Hybrid lymph node imaging using 64Cu-labeled mannose-conjugated human serum albumin with and without indocyanine green.

PubMed

Kang, Choong Mo; An, Gwang Il; Choe, Yearn Seong

2015-10-01

Human serum albumin (HSA), which has 58 Lys residues, one Cys residue, and indocyanine green (ICG) adsorption sites, can be used as a multifunctional platform for the development of hybrid imaging probes. In this study, we prepared 64Cu-labeled mannose-conjugated HSA with and without ICG ([64Cu]1-ICG and [64Cu]1, respectively) and compared hybrid PET/near-infrared fluorescence (NIRF) imaging with positron emission tomography (PET)/Cerenkov luminescence (CL) imaging of lymph nodes (LNs). 1,4,7,10-Tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid (DOTA)/mannose-conjugated HSA (1) was synthesized by conjugating mannose molecules to Lys residues and a DOTA molecule to a Cys residue of HSA. Compound 1 was then labeled with Cu ([64Cu]1), and the resulting [64Cu]1 was adsorbed with ICG ([64Cu]1-ICG). PET/NIRF or PET/CL imaging and subsequent biodistribution studies were performed in ICR mice after injection of the probes into the foot pads. The numbers of mannose and DOTA molecules conjugated to HSA were 7.17 ± 0.49 and 0.95 ± 0.18, respectively. The site-specific conjugation of one DOTA molecule to HSA was sufficient for 64Cu-labeling with high efficiency (96.0 ± 1.1%). PET/NIRF and PET/CL imaging and subsequent biodistribution studies demonstrated that the probes were avidly taken up by the popliteal LNs (PO), with a slightly higher uptake ratio of the PO to the lumbar LNs by [64Cu]1. In-vivo studies suggest that [64Cu]1 has more specific and selective binding to mannose receptors in the PO than [64Cu]1-ICG.

Fluorescence-guided mapping of sentinel lymph nodes in gynecological malignancies

NASA Astrophysics Data System (ADS)

Hirsch, Ole; Szyc, Łukasz; Muallem, Mustafa Zelal; Ignat, Iulia; Chekerov, Radoslav; Macdonald, Rainer; Sehouli, Jalid; Braicu, Ioana; Grosenick, Dirk

2017-07-01

We have successfully applied a custom-made handheld fluorescence camera for intraoperative fluorescence detection of indocyanine green in a feasibility study on sentinel lymph node mapping in patients with vulvar, cervical, endometrial and ovarian cancer.

Revealing Fermi arcs and Weyl nodes in MoTe2 by quasiparticle interference mapping

NASA Astrophysics Data System (ADS)

Deng, Peng; Xu, Zhilin; Deng, Ke; Zhang, Kenan; Wu, Yang; Zhang, Haijun; Zhou, Shuyun; Chen, Xi

2017-06-01

A Weyl semimetal exhibits unique properties with Weyl nodes in the bulk and Fermi arcs on the surface. Recently, MoTe2 was found to be a type-II Weyl semimetal, providing a platform for realizing these Weyl physics. Here, we report visualization of topological surface states on the surface of MoTe2 using a scanning tunneling microscope. Scattering between topological states forms quasiparticle interference (QPI) patterns in the Fourier transform of conductance maps. The complete existence of topological surface states in energy momentum space is revealed by d I /d V mapping. By comparing QPI results with a first-principles calculation, we further unveil the locations of Weyl nodes in the surface Brillouin zone. Our work provides spectroscopic information in the unoccupied states, especially those around the Weyl nodes energy, demonstrating the node-arc correlation in Weyl semimetals.

Comparative Effects of Computer-Based Concept Maps, Refutational Texts, and Expository Texts on Science Learning

ERIC Educational Resources Information Center

Adesope, Olusola O.; Cavagnetto, Andy; Hunsu, Nathaniel J.; Anguiano, Carlos; Lloyd, Joshua

2017-01-01

This study used a between-subjects experimental design to examine the effects of three different computer-based instructional strategies (concept map, refutation text, and expository scientific text) on science learning. Concept maps are node-link diagrams that show concepts as nodes and relationships among the concepts as labeled links.…

F-18 labelled PSMA-1007: biodistribution, radiation dosimetry and histopathological validation of tumor lesions in prostate cancer patients.

PubMed

Giesel, Frederik L; Hadaschik, B; Cardinale, J; Radtke, J; Vinsensia, M; Lehnert, W; Kesch, C; Tolstov, Y; Singer, S; Grabe, N; Duensing, S; Schäfer, M; Neels, O C; Mier, W; Haberkorn, U; Kopka, K; Kratochwil, C

2017-04-01

The prostate-specific membrane antigen (PSMA) targeted positron-emitting-tomography (PET) tracer 68 Ga-PSMA-11 shows great promise in the detection of prostate cancer. However, 68 Ga has several shortcomings as a radiolabel including short half-life and non-ideal energies, and this has motivated consideration of 18 F-labelled analogs. 18 F-PSMA-1007 was selected among several 18 F-PSMA-ligand candidate compounds because it demonstrated high labelling yields, outstanding tumor uptake and fast, non-urinary background clearance. Here, we describe the properties of 18 F-PSMA-1007 in human volunteers and patients. Radiation dosimetry of 18 F-PSMA-1007 was determined in three healthy volunteers who underwent whole-body PET-scans and concomitant blood and urine sampling. Following this, ten patients with high-risk prostate cancer underwent 18 F-PSMA-1007 PET/CT (1 h and 3 h p.i.) and normal organ biodistribution and tumor uptakes were examined. Eight patients underwent prostatectomy with extended pelvic lymphadenectomy. Uptake in intra-prostatic lesions and lymph node metastases were correlated with final histopathology, including PSMA immunostaining. With an effective dose of approximately 4.4-5.5 mSv per 200-250 MBq examination, 18 F-PSMA-1007 behaves similar to other PSMA-PET agents as well as to other 18 F-labelled PET-tracers. In comparison to other PSMA-targeting PET-tracers, 18 F-PSMA-1007 has reduced urinary clearance enabling excellent assessment of the prostate. Similar to 18 F-DCFPyL and with slightly slower clearance kinetics than PSMA-11, favorable tumor-to-background ratios are observed 2-3 h after injection. In eight patients, diagnostic findings were successfully validated by histopathology. 18 F-PSMA-1007 PET/CT detected 18 of 19 lymph node metastases in the pelvis, including nodes as small as 1 mm in diameter. 18 F-PSMA-1007 performs at least comparably to 68 Ga-PSMA-11, but its longer half-life combined with its superior energy characteristics and non-urinary excretion overcomes some practical limitations of 68 Ga-labelled PSMA-targeted tracers.

Concordance between peri-areolar blue dye and peri-incisional radiotracer injections for sentinel node mapping in patients with a history of primary breast cancer excisonal biopsy.

PubMed

Mehrabibahar, M; Azizi, S; Jangjoo, A; Saremi, E; Kakhki, V R Dabbagh; Sadeghi, R; Chicken, D W; Keshtgar, M

2014-01-01

We evaluated the concordance between peri-areolar blue dye and peri-incisional radiotracer injections for axillary sentinel node mapping of patients with the history of previous breast lesion excisional biopsy. 80 patients with the history of previous excisional biopsy of the breast lesions were included. All patients received two injections of 99mTc-antimony sulfide colloid in both ends of incision line in an intradermal fashion. 2 mL patient blue V dye was injection to all patients in the peri-areolar area of the index quadrant after induction of anesthesia. All blue or hot nodes were harvested as sentinel lymph nodes. At least one sentinel node could be detected during surgery in 79 patients. In total 94 sentinel nodes were detected. All detected sentinel nodes were hot. In three patients sentinel nodes were detected by gamma probe but not blue dye. The tumor location in all of these patients was in the upper lateral quadrant and the incision line was extended into the axillary tail of the breast in all of them. 91 out of 94 sentinel nodes were stained blue, which amounts to 95.8% concordance between blue dye and radiotracer on a per node analysis. Single peri-areolar injection in the index quadrant would suffice for sentinel node mapping of patients with history of excisional biopsy. Care should be taken in patients with large excisional biopsy in the extreme proximity to axilla.

Mediastinal lymph node detection and station mapping on chest CT using spatial priors and random forest

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Jiamin; Hoffman, Joanne; Zhao, Jocelyn

2016-07-15

Purpose: To develop an automated system for mediastinal lymph node detection and station mapping for chest CT. Methods: The contextual organs, trachea, lungs, and spine are first automatically identified to locate the region of interest (ROI) (mediastinum). The authors employ shape features derived from Hessian analysis, local object scale, and circular transformation that are computed per voxel in the ROI. Eight more anatomical structures are simultaneously segmented by multiatlas label fusion. Spatial priors are defined as the relative multidimensional distance vectors corresponding to each structure. Intensity, shape, and spatial prior features are integrated and parsed by a random forest classifiermore » for lymph node detection. The detected candidates are then segmented by the following curve evolution process. Texture features are computed on the segmented lymph nodes and a support vector machine committee is used for final classification. For lymph node station labeling, based on the segmentation results of the above anatomical structures, the textual definitions of mediastinal lymph node map according to the International Association for the Study of Lung Cancer are converted into patient-specific color-coded CT image, where the lymph node station can be automatically assigned for each detected node. Results: The chest CT volumes from 70 patients with 316 enlarged mediastinal lymph nodes are used for validation. For lymph node detection, their system achieves 88% sensitivity at eight false positives per patient. For lymph node station labeling, 84.5% of lymph nodes are correctly assigned to their stations. Conclusions: Multiple-channel shape, intensity, and spatial prior features aggregated by a random forest classifier improve mediastinal lymph node detection on chest CT. Using the location information of segmented anatomic structures from the multiatlas formulation enables accurate identification of lymph node stations.« less

Towards optical spectroscopic anatomical mapping (OSAM) for lesion validation in cardiac tissue (Conference Presentation)

NASA Astrophysics Data System (ADS)

Singh-Moon, Rajinder P.; Zaryab, Mohammad; Hendon, Christine P.

2017-02-01

Electroanatomical mapping (EAM) is an invaluable tool for guiding cardiac radiofrequency ablation (RFA) therapy. The principle roles of EAM is the identification of candidate ablation sites by detecting regions of abnormal electrogram activity and lesion validation subsequent to RF energy delivery. However, incomplete lesions may present interim electrical inactivity similar to effective treatment in the acute setting, despite efforts to reveal them with pacing or drugs, such as adenosine. Studies report that the misidentification and recovery of such lesions is a leading cause of arrhythmia recurrence and repeat procedures. In previous work, we demonstrated spectroscopic characterization of cardiac tissues using a fiber optic-integrated RF ablation catheter. In this work, we introduce OSAM (optical spectroscopic anatomical mapping), the application of this spectroscopic technique to obtain 2-dimensional biodistribution maps. We demonstrate its diagnostic potential as an auxiliary method for lesion validation in treated swine preparations. Endocardial lesion sets were created on fresh swine cardiac samples using a commercial RFA system. An optically-integrated catheter console fabricated in-house was used for measurement of tissue optical spectra between 600-1000nm. Three dimensional, Spatio-spectral datasets were generated by raster scanning of the optical catheter across the treated sample surface in the presence of whole blood. Tissue optical parameters were recovered at each spatial position using an inverse Monte Carlo method. OSAM biodistribution maps showed stark correspondence with gross examination of tetrazolium chloride stained tissue specimens. Specifically, we demonstrate the ability of OSAM to readily distinguish between shallow and deeper lesions, a limitation faced by current EAM techniques. These results showcase the OSAMs potential for lesion validation strategies for the treatment of cardiac arrhythmias.

Multiadaptive Plan (MAP) IMRT to Accommodate Independent Movement of the Prostate and Pelvic Lymph Nodes

DTIC Science & Technology

2013-06-01

08-1-0358 TITLE: Multiadaptive Plan (MAP) IMRT to Accommodate Independent Movement of the Prostate and Pelvic Lymph Nodes PRINCIPAL...AND SUBTITLE Multi-Adaptive Plan (MAP) IMRT to Accommodate Independent 5a. CONTRACT NUMBER W81XWH-08-1-0358 Movement of the Prostate and...multi-adaptive plan (MAP) IMRT to accommodate independent movement of the two targeted tumor volumes. In this project, we evaluated two adaptive

Peripherally Administered Nanoparticles Target Monocytic Myeloid Cells, Secondary Lymphoid Organs and Tumors in Mice

PubMed Central

Kourtis, Iraklis C.; Hirosue, Sachiko; de Titta, Alexandre; Kontos, Stephan; Stegmann, Toon; Hubbell, Jeffrey A.; Swartz, Melody A.

2013-01-01

Nanoparticles have been extensively developed for therapeutic and diagnostic applications. While the focus of nanoparticle trafficking in vivo has traditionally been on drug delivery and organ-level biodistribution and clearance, recent work in cancer biology and infectious disease suggests that targeting different cells within a given organ can substantially affect the quality of the immunological response. Here, we examine the cell-level biodistribution kinetics after administering ultrasmall Pluronic-stabilized poly(propylene sulfide) nanoparticles in the mouse. These nanoparticles depend on lymphatic drainage to reach the lymph nodes and blood, and then enter the spleen rather than the liver, where they interact with monocytes, macrophages and myeloid dendritic cells. They were more readily taken up into lymphatics after intradermal (i.d.) compared to intramuscular administration, leading to ∼50% increased bioavailability in blood. When administered i.d., their distribution favored antigen-presenting cells, with especially strong targeting to myeloid cells. In tumor-bearing mice, the monocytic and the polymorphonuclear myeloid-derived suppressor cell compartments were efficiently and preferentially targeted, rendering this nanoparticulate formulation potentially useful for reversing the highly suppressive activity of these cells in the tumor stroma. PMID:23626707

Peripherally administered nanoparticles target monocytic myeloid cells, secondary lymphoid organs and tumors in mice.

PubMed

Kourtis, Iraklis C; Hirosue, Sachiko; de Titta, Alexandre; Kontos, Stephan; Stegmann, Toon; Hubbell, Jeffrey A; Swartz, Melody A

2013-01-01

Nanoparticles have been extensively developed for therapeutic and diagnostic applications. While the focus of nanoparticle trafficking in vivo has traditionally been on drug delivery and organ-level biodistribution and clearance, recent work in cancer biology and infectious disease suggests that targeting different cells within a given organ can substantially affect the quality of the immunological response. Here, we examine the cell-level biodistribution kinetics after administering ultrasmall Pluronic-stabilized poly(propylene sulfide) nanoparticles in the mouse. These nanoparticles depend on lymphatic drainage to reach the lymph nodes and blood, and then enter the spleen rather than the liver, where they interact with monocytes, macrophages and myeloid dendritic cells. They were more readily taken up into lymphatics after intradermal (i.d.) compared to intramuscular administration, leading to ∼50% increased bioavailability in blood. When administered i.d., their distribution favored antigen-presenting cells, with especially strong targeting to myeloid cells. In tumor-bearing mice, the monocytic and the polymorphonuclear myeloid-derived suppressor cell compartments were efficiently and preferentially targeted, rendering this nanoparticulate formulation potentially useful for reversing the highly suppressive activity of these cells in the tumor stroma.

Biodistribution and safety of a live attenuated tetravalent dengue vaccine in the cynomolgus monkey.

PubMed

Ravel, Guillaume; Mantel, Nathalie; Silvano, Jeremy; Rogue, Alexandra; Guy, Bruno; Jackson, Nicholas; Burdin, Nicolas

2017-10-13

The first licensed dengue vaccine is a recombinant, live, attenuated, tetravalent dengue virus vaccine (CYD-TDV; Sanofi Pasteur). This study assessed the biodistribution, shedding, and toxicity of CYD-TDV in a non-human primate model as part of the nonclinical safety assessment program for the vaccine. Cynomolgus monkeys were given one subcutaneous injection of either one human dose (5log 10 CCID 50 /serotype) of CYD-TDV or saline control. Study endpoints included clinical observations, body temperature, body weight, food consumption, clinical pathology, immunogenicity, and post-mortem examinations including histopathology. Viral load, distribution, persistence, and shedding in tissues and body fluids were evaluated by quantitative reverse transcriptase polymerase chain reaction. The subcutaneous administration of CYD-TDV was well tolerated. There were no toxicological findings other than expected minor local reactions at the injection site. A transient low level of CYD-TDV viral RNA was detected in blood and the viral genome was identified primarily at the injection site and in the draining lymph nodes following immunization. These results, together with other data from repeat-dose toxicity and neurovirulence studies, confirm the absence of toxicological concern with CYD-TDV and corroborate clinical study observations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Network geometry inference using common neighbors

NASA Astrophysics Data System (ADS)

Papadopoulos, Fragkiskos; Aldecoa, Rodrigo; Krioukov, Dmitri

2015-08-01

We introduce and explore a method for inferring hidden geometric coordinates of nodes in complex networks based on the number of common neighbors between the nodes. We compare this approach to the HyperMap method, which is based only on the connections (and disconnections) between the nodes, i.e., on the links that the nodes have (or do not have). We find that for high degree nodes, the common-neighbors approach yields a more accurate inference than the link-based method, unless heuristic periodic adjustments (or "correction steps") are used in the latter. The common-neighbors approach is computationally intensive, requiring O (t4) running time to map a network of t nodes, versus O (t3) in the link-based method. But we also develop a hybrid method with O (t3) running time, which combines the common-neighbors and link-based approaches, and we explore a heuristic that reduces its running time further to O (t2) , without significant reduction in the mapping accuracy. We apply this method to the autonomous systems (ASs) Internet, and we reveal how soft communities of ASs evolve over time in the similarity space. We further demonstrate the method's predictive power by forecasting future links between ASs. Taken altogether, our results advance our understanding of how to efficiently and accurately map real networks to their latent geometric spaces, which is an important necessary step toward understanding the laws that govern the dynamics of nodes in these spaces, and the fine-grained dynamics of network connections.

INDIRECT COMPUTED TOMOGRAPHIC LYMPHOGRAPHY FOR ILIOSACRAL LYMPHATIC MAPPING IN A COHORT OF DOGS WITH ANAL SAC GLAND ADENOCARCINOMA: TECHNIQUE DESCRIPTION.

PubMed

Majeski, Stephanie A; Steffey, Michele A; Fuller, Mark; Hunt, Geraldine B; Mayhew, Philipp D; Pollard, Rachel E

2017-05-01

Sentinel lymph node mapping can help to direct surgical oncologic staging and metastatic disease detection in patients with complex lymphatic pathways. We hypothesized that indirect computed tomographic lymphography (ICTL) with a water-soluble iodinated contrast agent would successfully map lymphatic pathways of the iliosacral lymphatic center in dogs with anal sac gland carcinoma, providing a potential preoperative method for iliosacral sentinel lymph node identification in dogs. Thirteen adult dogs diagnosed with anal sac gland carcinoma were enrolled in this prospective, pilot study, and ICTL was performed via peritumoral contrast injection with serial caudal abdominal computed tomography scans for iliosacral sentinel lymph node identification. Technical and descriptive details for ICTL were recorded, including patient positioning, total contrast injection volume, timing of contrast visualization, and sentinel lymph nodes and lymphatic pathways identified. Indirect CT lymphography identified lymphatic pathways and sentinel lymph nodes in 12/13 cases (92%). Identified sentinel lymph nodes were ipsilateral to the anal sac gland carcinoma in 8/12 and contralateral to the anal sac gland carcinoma in 4/12 cases. Sacral, internal iliac, and medial iliac lymph nodes were identified as sentinel lymph nodes, and patterns were widely variable. Patient positioning and timing of imaging may impact successful sentinel lymph node identification. Positioning in supported sternal recumbency is recommended. Results indicate that ICTL may be a feasible technique for sentinel lymph node identification in dogs with anal sac gland carcinoma and offer preliminary data to drive further investigation of iliosacral lymphatic metastatic patterns using ICTL and sentinel lymph node biopsy. © 2017 American College of Veterinary Radiology.

Sentinel node mapping in endometrial cancer following Hysteroscopic injection of tracers: A single center evaluation over 200 cases.

PubMed

Martinelli, Fabio; Ditto, Antonino; Signorelli, Mauro; Bogani, Giorgio; Chiappa, Valentina; Lorusso, Domenica; Scaffa, Cono; Recalcati, Dario; Perotto, Stefania; Haeusler, Edward; Raspagliesi, Francesco

2017-09-01

To analyze detection-rate(DR) and diagnostic-accuracy (A) of sentinel-nodes(SLNs) mapping following hysteroscopic-injection of tracer. To compare DR and A between tracers: ICG and Tc99m. Evaluation of endometrial-cancer patients who underwent SLNs mapping after hysteroscopic-peritumoral-injection of tracer±lymphadenectomy. Analysis of DR (overall-bilateral-aortic) and A in the entire cohort and comparison between tracers. 202 procedures were performed from January/2005 to February/2017. Mean age:60years (28-82); mean BMI: 26.8 kg/m 2 (15-47). In 133 cases (65.8%) hysterectomy and mapping procedure were performed laparoscopically. The overall-DR of the technique was 93.2% (179/192) (10 cases were excluded: 9 for technical-equipment failure; 1 for vagal reaction). Bilateral pelvic mapping was found in 59.7% of cases (107/179) and was more frequent in the ICG group (72.8% vs 53.3%; p: 0.012). In 50.8% of cases (91/179) SLNs were mapped both in pelvic and aortic nodes, and in 5 cases (2.8%) only in the aortic area. The mean number of detected SLNs was 3.7 (1-8). 22 patients (12.3%) had nodal involvement: 10-(45.5%)-macrometastases; 5-(22.7%)-micrometastases; 7-(31.8%)-ITCs. In 6 cases (27.3%) only aortic nodes were positive; in 5 cases (22.7%) both pelvic and aortic nodes and in 11 cases (50%) only pelvic nodes were involved. Three false-negative results were found, all in the Tc99m group. All had isolated aortic metastases with negative pelvic nodes. Overall-sensitivity was 86.4% (95%CI: 68.4-100) and overall-negative-predictive-value (NPV) was 96.4% (95%CI 86.7-100). No differences in terms of overall-DR, overall-sensitivity and overall-NPV were found between the two tracers. Hysteroscopic-injection of tracer for SLNs mapping in endometrial cancer is as accurate as cervical injection with a higher DR in the aortic area. ICG improves bilateral-DR. Further investigation is warranted on this topic. Copyright © 2017 Elsevier Inc. All rights reserved.

Laparoscopic Sentinel Lymph Node Mapping with Indocyanine Green Using the iSpies Platform: Initial Experience Argentina.

PubMed

Di Guilmi, Julian; Darin, Maria Cecilia; Toscano, Maria; Maya, Gustavo

To demonstrate the initial experience in Argentina using the iSpies indocyanine green (ICG) platform in sentinel lymph node mapping in patients with early-stage cervical cancer. Step-by-step demonstration of the technique using a video and pictures (educative video) (Canadian Task Force classification III). Laparoscopic and robotic sentinel lymph node mapping using ICG has been shown to be safe and feasible; however, in developing countries, the opportunities to use fluorescent imaging through a minimally invasive approach are very limited, given the cost restrictions of acquiring the near-infrared technology and the fluorescent dyes. A 47-year-old woman presented with a stage IB1 squamous cervical cancer. Physical examination revealed a 1.5-cm tumor without evidence of parametrial involvement. Magnetic resonance imaging did not show any evidence of metastatic disease. The patient underwent laparoscopic radical hysterectomy with sentinel lymph node mapping. On laparoscopic exposure of the pelvic spaces, a cervical injection of ICG (1 mL superficial and deep) was administered using a spinal needle at the 3 o'clock and 9 o'clock positions. Sentinel lymph node mapping was then performed using the ICG (Pulsion Medical Systems, Feldkirchen, Germany) and an iSpies near-infrared camera (Karl Storz Endoskope, Tuttlingen, Germany). Bilateral sentinel lymph nodes were detected on the left external iliac artery and in the right obturator space. Both were confirmed ex vivo. The total operative time was 170 minutes. No intraoperative or postoperative complications were reported, and the patient was discharged at 48 hours after surgery. Estimated blood loss was minimal. Sentinel lymph node mapping alone is not the standard of care in our institution, and thus bilateral lymphadenectomy was performed. Ultrastaging is routinely performed when a sentinel lymph node is evaluated. Final pathology revealed a tumor confined to the cervix, with tumor-free margins, and a total of 10 lymph nodes that were negative for any evidence of disease. Disadvantages of this technology compared with the Pinpoint ICG system (Novadaq Technologies; Bonita Springs, FL) is the lack of simultaneous white vision and fluorescence ICG detection, and the to manually change normal vision to infrared vision. An advantage of the Storz iSpies system is its availability in our country, considering that the technology developed by Novadaq is not yet approved in Argentina. Although ICG sentinel lymph node mapping is becoming a standard of care [1,2], a lack of ICG dye or laparoscopic near-infrared technologies could be a deterrent to its use in developing countries. A focus on expanding this technology in countries with limited resources would allow patients the opportunity to avoid the morbidity associated with full lymphadenectomy. Copyright © 2017 American Association of Gynecologic Laparoscopists. Published by Elsevier Inc. All rights reserved.

One-Step Nucleic Acid Amplification (OSNA): A fast molecular test based on CK19 mRNA concentration for assessment of lymph-nodes metastases in early stage endometrial cancer.

PubMed

Fanfani, Francesco; Monterossi, Giorgia; Ghizzoni, Viola; Rossi, Esther D; Dinoi, Giorgia; Inzani, Frediano; Fagotti, Anna; Gueli Alletti, Salvatore; Scarpellini, Francesca; Nero, Camilla; Santoro, Angela; Scambia, Giovanni; Zannoni, Gian F

2018-01-01

The aim of the current study is to evaluate the detection rate of micro- and macro-metastases of the One-Step Nucleic Acid Amplification (OSNA) compared to frozen section examination and subsequent ultra-staging examination in early stage endometrial cancer (EC). From March 2016 to June 2016, data of 40 consecutive FIGO stage I EC patients were prospectively collected in an electronic database. The sentinel lymph node mapping was performed in all patients. All mapped nodes were removed and processed. Sentinel lymph nodes were sectioned and alternate sections were respectively examined by OSNA and by frozen section analysis. After frozen section, the residual tissue from each block was processed with step-level sections (each step at 200 micron) including H&E and IHC slides. Sentinel lymph nodes mapping was successful in 29 patients (72.5%). In the remaining 11 patients (27.5%), a systematic pelvic lymphadenectomy was performed. OSNA assay sensitivity and specificity were 87.5% and 100% respectively. Positive and negative predictive values were 100% and 99% respectively, with a diagnostic accuracy of 99%. As far as frozen section examination and subsequent ultra-staging analysis was concerned, we reported sensitivity and specificity of 50% and 94.4% respectively; positive and negative predictive values were 14.3% and 99%, respectively, with an accuracy of 93.6%. In one patient, despite negative OSNA and frozen section analysis of the sentinel node, a macro-metastasis in 1 non-sentinel node was found. The combination of OSNA procedure with the sentinel lymph node mapping could represent an efficient intra-operative tool for the selection of early-stage EC patients to be submitted to systematic lymphadenectomy.

Axillary reverse mapping with indocyanine green or isosulfan blue demonstrate similar crossover rates to radiotracer identified sentinel nodes.

PubMed

Foster, Deshka; Choy, Nicole; Porter, Catherine; Ahmed, Shushmita; Wapnir, Irene

2018-03-01

Sentinel lymph node (SLN) resection is imperative for breast cancer staging. Axillary reverse mapping (ARM) can preserve arm draining nodes and lymphatics during surgery. ARM is generally performed with isosulfan blue (ISB), restricting its use for concurrent SLN biopsy. Indocyanine green (ICG) could serve as an alternative to ISB for ARM procedures. SLN mapping and biopsy was performed via periareolar injection of 99 technetium-sulfur colloid ( 99m TcSc, TSC). ISB and ICG were injected in the upper arm. Blue-stained lymphatics or nodes were visualized in the axilla; ICG was identified using the SPY Elite® system. Twenty-three patients underwent SLN biopsy with or without axillary node dissection and ARM procedures. Twenty of these patients had at least one hot node; 12 patients had SLNs that were only hot, 6 hot/blue/fluorescent, and 2 hot/fluorescent. Overall, crossover of ARM agents with SLNs occurred in 8 cases. Inspection of the axillary cavity after SLN biopsy revealed fluorescent lymphatics and nodes remaining in 14 and 7 patients, respectively. Blue lymphatics and blue nodes were detected in fewer cases. Nearly one-third of patients showed crossover between breast and arm draining nodes, which provides insight as to why some patients develop lymphedema symptoms after SLN biopsy. ICG and ISB identify similar numbers of SLNs. As such ICG could substitute for ISB in ARM procedures. © 2017 Wiley Periodicals, Inc.

Dealing with Liars: Misbehavior Identification via Rényi-Ulam Games

NASA Astrophysics Data System (ADS)

Kozma, William; Lazos, Loukas

We address the problem of identifying misbehaving nodes that refuse to forward packets in wireless multi-hop networks. We map the process of locating the misbehaving nodes to the classic Rényi-Ulam game of 20 questions. Compared to previous methods, our mapping allows the evaluation of node behavior on a per-packet basis, without the need for energy-expensive overhearing techniques or intensive acknowledgment schemes. Furthermore, it copes with colluding adversaries that coordinate their behavioral patterns to avoid identification and frame honest nodes. We show via simulations that our algorithms reduce the communication overhead for identifying misbehaving nodes by at least one order of magnitude compared to other methods, while increasing the identification delay logarithmically with the path size.

Flexible embedding of networks

NASA Astrophysics Data System (ADS)

Fernandez-Gracia, Juan; Buckee, Caroline; Onnela, Jukka-Pekka

We introduce a model for embedding one network into another, focusing on the case where network A is much bigger than network B. Nodes from network A are assigned to the nodes in network B using an algorithm where we control the extent of localization of node placement in network B using a single parameter. Starting from an unassigned node in network A, called the source node, we first map this node to a randomly chosen node in network B, called the target node. We then assign the neighbors of the source node to the neighborhood of the target node using a random walk based approach. To assign each neighbor of the source node to one of the nodes in network B, we perform a random walk starting from the target node with stopping probability α. We repeat this process until all nodes in network A have been mapped to the nodes of network B. The simplicity of the model allows us to calculate key quantities of interest in closed form. By varying the parameter α, we are able to produce embeddings from very local (α = 1) to very global (α --> 0). We show how our calculations fit the simulated results, and we apply the model to study how social networks are embedded in geography and how the neurons of C. Elegans are embedded in the surrounding volume.

A pilot study of lymph node mapping with indocyanine green in robotic gastrectomy for gastric cancer.

PubMed

Lan, Yuan-Tzu; Huang, Kuo-Hung; Chen, Ping-Hsien; Liu, Chien-An; Lo, Su-Shun; Wu, Chew-Wun; Shyr, Yi-Ming; Fang, Wen-Liang

2017-01-01

Robotic gastrectomy has become increasingly popular in the treatment of gastric cancer, especially in Asian countries. The use of indocyanine green fluorescence has been reported in lymphatic mapping for gastric cancer in laparoscopic gastrectomy; however, there have been few reports regarding the use of indocyanine green in robotic gastrectomy. From January 2011 to March 2016, a total of 79 patients underwent robotic gastrectomy for gastric cancer. Among them, intraoperative subserosal injection (n = 9) or preoperative submucosal injection (n = 5) of indocyanine green with near-infrared imaging was performed in 14 patients, and the other 65 patients underwent robotic gastrectomy without the use of indocyanine green. There was no significant difference in the operative time, total number of retrieved lymph nodes, operative blood loss, and postoperative hospital stay between the patients who underwent robotic gastrectomy with or without indocyanine green fluorescence. For each lymph node station, there was significantly more number of retrieved lymph nodes in the indocyanine green group than in the no-indocyanine green group at the greater curvature side of the low body (#4d) to the infrapyloric region (#6) of the stomach. Five of the 14 patients who received an indocyanine green injection for lymphatic mapping had lymph node metastasis, and metastatic lymph nodes were located in the lymph node stations as detected by indocyanine green fluorescence during surgery. Indocyanine green fluorescence with near-infrared imaging is feasible and is a promising method of lymphatic mapping in robotic gastrectomy for gastric cancer. In future studies, larger patient numbers and long-term follow-up are required.

Computed tomographic atlas for the new international lymph node map for lung cancer: A radiation oncologist perspective.

PubMed

Lynch, Rod; Pitson, Graham; Ball, David; Claude, Line; Sarrut, David

2013-01-01

To develop a reproducible definition for each mediastinal lymph node station based on the new TNM classification for lung cancer. This paper proposes an atlas using the new international lymph node map used in the seventh edition of the TNM classification for lung cancer. Four radiation oncologists and 1 diagnostic radiologist were involved in the project to put forward a reproducible radiologic description for the lung lymph node stations. The International Association for the Study of Lung Cancer lymph node definitions for stations 1 to 11 have been described and illustrated on axial computed tomographic scan images using a certified radiotherapy planning system. This atlas will assist both diagnostic radiologists and radiation oncologists in accurately defining the lymph node stations on computed tomographic scan in patients diagnosed with lung cancer. Copyright © 2013 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

Sentinel lymph node detection in gynecologic malignancies by a handheld fluorescence camera

NASA Astrophysics Data System (ADS)

Hirsch, Ole; Szyc, Lukasz; Muallem, Mustafa Zelal; Ignat, Iulia; Chekerov, Radoslav; Macdonald, Rainer; Sehouli, Jalid; Braicu, Ioana; Grosenick, Dirk

2017-02-01

Near-infrared fluorescence imaging using indocyanine green (ICG) as a tracer is a promising technique for mapping the lymphatic system and for detecting sentinel lymph nodes (SLN) during cancer surgery. In our feasibility study we have investigated the application of a custom-made handheld fluorescence camera system for the detection of lymph nodes in gynecological malignancies. It comprises a low cost CCD camera with enhanced NIR sensitivity and two groups of LEDs emitting at wavelengths of 735 nm and 830 nm for interlaced recording of fluorescence and reflectance images of the tissue, respectively. With the help of our system, surgeons can observe fluorescent tissue structures overlaid onto the anatomical image on a monitor in real-time. We applied the camera system for intraoperative lymphatic mapping in 5 patients with vulvar cancer, 5 patients with ovarian cancer, 3 patients with cervical cancer, and 3 patients with endometrial cancer. ICG was injected at four loci around the primary malignant tumor during surgery. After a residence time of typically 15 min fluorescence images were taken in order to visualize the lymph nodes closest to the carcinomas. In cases with vulvar cancer about half of the lymph nodes detected by routinely performed radioactive SLN mapping have shown fluorescence in vivo as well. In the other types of carcinomas several lymph nodes could be detected by fluorescence during laparotomy. We conclude that our low cost camera system has sufficient sensitivity for lymphatic mapping during surgery.

Near infrared imaging to identify sentinel lymph nodes in invasive urinary bladder cancer

NASA Astrophysics Data System (ADS)

Knapp, Deborah W.; Adams, Larry G.; Niles, Jacqueline D.; Lucroy, Michael D.; Ramos-Vara, Jose; Bonney, Patty L.; deGortari, Amalia E.; Frangioni, John V.

2006-02-01

Approximately 12,000 people are diagnosed with invasive transitional cell carcinoma of the urinary bladder (InvTCC) each year in the United States. Surgical removal of the bladder (cystectomy) and regional lymph node dissection are considered frontline therapy. Cystectomy causes extensive acute morbidity, and 50% of patients with InvTCC have occult metastases at the time of diagnosis. Better staging procedures for InvTCC are greatly needed. This study was performed to evaluate an intra-operative near infrared fluorescence imaging (NIRF) system (Frangioni laboratory) for identifying sentinel lymph nodes draining InvTCC. NIRF imaging was used to map lymph node drainage from specific quadrants of the urinary bladder in normal dogs and pigs, and to map lymph node drainage from naturally-occurring InvTCC in pet dogs where the disease closely mimics the human condition. Briefly, during surgery NIR fluorophores (human serum albumen-fluorophore complex, or quantum dots) were injected directly into the bladder wall, and fluorescence observed in lymphatics and regional nodes. Conditions studied to optimize the procedure including: type of fluorophore, depth of injection, volume of fluorophore injected, and degree of bladder distention at the time of injection. Optimal imaging occurred with very superficial injection of the fluorophore in the serosal surface of the moderately distended bladder. Considerable variability was noted from dog to dog in the pattern of lymph node drainage. NIR fluorescence was noted in lymph nodes with metastases in dogs with InvTCC. In conclusion, intra-operative NIRF imaging is a promising approach to improve sentinel lymph node mapping in invasive urinary bladder cancer.

Lymphatic mapping and sentinel node biopsy in ovarian tumors: a study using intra-operative Tc-99m-Phytate and lymphoscintigraphy imaging.

PubMed

Hassanzadeh, Malihe; Hosseini Farahabadi, Elham; Yousefi, Zohreh; Kadkhodayan, Sima; Zarifmahmoudi, Leili; Sadeghi, Ramin

2016-09-07

Experience on sentinel node mapping in ovarian tumors is very limited. We evaluated the sentinel node concept in ovarian tumors using intra-operativeTc-99m-Phytate injection and lymphoscintigraphy imaging. Thirty-five patients with a pelvic mass due to an ovarian pathology were included in the study. The radiotracer was injected just after laparotomy and before removal of the tumor either beneath the normal cortex (10 patients) or in the utero-ovarian and suspensory ligaments of the ovary just beneath the peritoneum two injections of the radiotracer (25 patients). For malignant masses, the sentinel nodes were identified using a hand held gamma probe. Then standard pelvic and para-aortic lymphadenectomy was performed. In case of benign pathologies or borderline ovarian tumors on frozen section, lymphadenectomy was not performed. The morning after surgery, all patients were sent for lymphoscintigraphy imaging of the abdomen and pelvis. Sentinel node was identified only in 4 patients of the cortical injection group. At least one sentinel node could be identified in 21 patients of the sub-peritoneal group. Sentinel nodes were identified only in the para-aortic area in 21, pelvic/para-aortic areas in 2, and pelvic only area in 2 patients. Three patients had lymph node involvement and all had involved sentinel nodes (no false negative case). Sentinel node mapping using intra-operative injection of the radiotracer (in the utero-ovarian and suspensory ligaments of the ovary just beneath the peritoneum) is feasible in ovarian tumors. Technical aspects of this method should be explored in larger multicenter studies in the future.

Inclusive jet cross sections in proton-proton collisions at 7.0 TeV center-of-mass energy with the ATLAS detector at the Large Hadron Collider

NASA Astrophysics Data System (ADS)

Park-Martinez, Jayne Irene

The purpose of this study was to assess the effects of node-link mapping on students' meaningful learning and conceptual change in a 1-semester introductory life-science course. This study used node-link mapping to integrate and apply the National Research Council's (NRC, 2005) three principles of human learning: engaging students' prior knowledge, fostering their metacognition, and supporting their formulation of a scientific conceptual framework. The study was a quasi-experimental, pretest-posttest, control group design. The sample consisted of 68 primarily freshmen non-science majors enrolled in two intact sections of the targeted course. Both groups received the same teacher-centered instruction and student-centered activities designed to promote meaningful learning and conceptual change; however, the activity format differed. Control group activities were written; treatment group activities were node-link mapped. Prior to instruction, both groups demonstrated equivalent knowledge and misconceptions associated with genetics and evolution (GE), and ecology and environmental science (EE). Mean differences, pre-to-post instruction, on the GE and EE meaningful learning exam scores and the EE conceptual change inventory scores between the writing group (control) and the node-link mapping group (treatment) were analyzed using repeated measures MANOVAs. There were no significant mean pre-to-post differences between groups with respect to meaningful learning in the GE or EE units, or conceptual change in the EE unit. However, independent of group membership, the overall mean pre-to-post increases in meaningful learning and conceptual change were significant. These findings suggest that both node-link mapping and writing, when used in conjunction with the National Research Council's (NRC, 2005) three principles of human learning, can promote meaningful learning and conceptual change. The only significant interaction found with respect to meaningful learning, conceptual change, and learning styles (Kolb, 2005) was a positive effect of node-link mapping on converger's meaningful learning. However, that result was probably an artifact of small sample size rather than a true treatment effect. No other significant interactions were found. These results suggest that all students, regardless of their learning style, can benefit from either node-link mapping or writing to promote meaningful learning and conceptual change in general life-science courses.

Heterogeneous delays making parents synchronized: A coupled maps on Cayley tree model

NASA Astrophysics Data System (ADS)

Singh, Aradhana; Jalan, Sarika

2014-06-01

We study the phase synchronized clusters in the diffusively coupled maps on the Cayley tree networks for heterogeneous delay values. Cayley tree networks comprise of two parts: the inner nodes and the boundary nodes. We find that heterogeneous delays lead to various cluster states, such as; (a) cluster state consisting of inner nodes and boundary nodes, and (b) cluster state consisting of only boundary nodes. The former state may comprise of nodes from all the generations forming self-organized cluster or nodes from few generations yielding driven clusters depending upon on the parity of heterogeneous delay values. Furthermore, heterogeneity in delays leads to the lag synchronization between the siblings lying on the boundary by destroying the exact synchronization among them. The time lag being equal to the difference in the delay values. The Lyapunov function analysis sheds light on the destruction of the exact synchrony among the last generation nodes. To the end we discuss the relevance of our results with respect to their applications in the family business as well as in understanding the occurrence of genetic diseases.

System and method for image mapping and visual attention

NASA Technical Reports Server (NTRS)

Peters, II, Richard A. (Inventor)

2010-01-01

A method is described for mapping dense sensory data to a Sensory Ego Sphere (SES). Methods are also described for finding and ranking areas of interest in the images that form a complete visual scene on an SES. Further, attentional processing of image data is best done by performing attentional processing on individual full-size images from the image sequence, mapping each attentional location to the nearest node, and then summing attentional locations at each node.

System and method for image mapping and visual attention

NASA Technical Reports Server (NTRS)

Peters, II, Richard A. (Inventor)

2011-01-01

A method is described for mapping dense sensory data to a Sensory Ego Sphere (SES). Methods are also described for finding and ranking areas of interest in the images that form a complete visual scene on an SES. Further, attentional processing of image data is best done by performing attentional processing on individual full-size images from the image sequence, mapping each attentional location to the nearest node, and then summing all attentional locations at each node.

Sentinel lymph node mapping reduces practice pattern variations in surgical staging for endometrial adenocarcinoma: A before and after study.

PubMed

Liu, Christina Y; Elias, Kevin M; Howitt, Brooke E; Lee, Larissa J; Feltmate, Colleen M

2017-05-01

To examine the effects of universal sentinel lymph node mapping on the use of nodal staging in endometrial adenocarcinoma. Two approaches to laparoscopic staging for endometrial adenocarcinoma were compared using a before and after study design. The before cohort underwent selective lymphadenectomy from January 1, 2014-October 1, 2015 while the after cohort underwent universal sentinel lymph node (SLN) mapping from October 2, 2015-September 29, 2016. The before cohort comprised 215 patients and the after cohort 166 patients. In women undergoing SLN mapping, a sentinel node was identified at least unilaterally in 146/153 cases (95.4%), and bilaterally in 114/153 (74.5%) of cases. Pelvic nodes were removed in 35.8% of the before cohort versus 92.2% of the after cohort (p<0.0001) with more nodal evaluation among both low risk (9.6% vs. 91%, p<0.0001) and high risk cases (66% vs. 94%, p<0.0001). While the proportion of low risk cases diagnosed with nodal involvement did not significantly change (0.9% to 3.1%, p=0.32), there was a trend toward more diagnoses of nodal involvement in high risk cases (5% to 13.2%, p=0.06). Mean number of pelvic lymph nodes removed (15 vs. 4, p<0.0001), mean operative time (181min vs. 137min, p<0.0001), estimated blood loss (80ml vs. 56ml, p=0.004), and rate of post-operative complications (13% vs. 5.2%, p=0.04) all decreased after the adoption of SLN dissection. Universal sentinel lymph node dissection for laparoscopic endometrial cancer staging reduces heterogeneity in surgeon staging practice, increases nodal detection, and lowers post-operative complications. Copyright © 2017 Elsevier Inc. All rights reserved.

Parallel definition of tear film maps on distributed-memory clusters for the support of dry eye diagnosis.

PubMed

González-Domínguez, Jorge; Remeseiro, Beatriz; Martín, María J

2017-02-01

The analysis of the interference patterns on the tear film lipid layer is a useful clinical test to diagnose dry eye syndrome. This task can be automated with a high degree of accuracy by means of the use of tear film maps. However, the time required by the existing applications to generate them prevents a wider acceptance of this method by medical experts. Multithreading has been previously successfully employed by the authors to accelerate the tear film map definition on multicore single-node machines. In this work, we propose a hybrid message-passing and multithreading parallel approach that further accelerates the generation of tear film maps by exploiting the computational capabilities of distributed-memory systems such as multicore clusters and supercomputers. The algorithm for drawing tear film maps is parallelized using Message Passing Interface (MPI) for inter-node communications and the multithreading support available in the C++11 standard for intra-node parallelization. The original algorithm is modified to reduce the communications and increase the scalability. The hybrid method has been tested on 32 nodes of an Intel cluster (with two 12-core Haswell 2680v3 processors per node) using 50 representative images. Results show that maximum runtime is reduced from almost two minutes using the previous only-multithreaded approach to less than ten seconds using the hybrid method. The hybrid MPI/multithreaded implementation can be used by medical experts to obtain tear film maps in only a few seconds, which will significantly accelerate and facilitate the diagnosis of the dry eye syndrome. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Musician Map: visualizing music collaborations over time

NASA Astrophysics Data System (ADS)

Yim, Ji-Dong; Shaw, Chris D.; Bartram, Lyn

2009-01-01

In this paper we introduce Musician Map, a web-based interactive tool for visualizing relationships among popular musicians who have released recordings since 1950. Musician Map accepts search terms from the user, and in turn uses these terms to retrieve data from MusicBrainz.org and AudioScrobbler.net, and visualizes the results. Musician Map visualizes relationships of various kinds between music groups and individual musicians, such as band membership, musical collaborations, and linkage to other artists that are generally regarded as being similar in musical style. These relationships are plotted between artists using a new timeline-based visualization where a node in a traditional node-link diagram has been transformed into a Timeline-Node, which allows the visualization of an evolving entity over time, such as the membership in a band. This allows the user to pursue social trend queries such as "Do Hip-Hop artists collaborate differently than Rock artists".

Application of Approximate Pattern Matching in Two Dimensional Spaces to Grid Layout for Biochemical Network Maps

PubMed Central

Inoue, Kentaro; Shimozono, Shinichi; Yoshida, Hideaki; Kurata, Hiroyuki

2012-01-01

Background For visualizing large-scale biochemical network maps, it is important to calculate the coordinates of molecular nodes quickly and to enhance the understanding or traceability of them. The grid layout is effective in drawing compact, orderly, balanced network maps with node label spaces, but existing grid layout algorithms often require a high computational cost because they have to consider complicated positional constraints through the entire optimization process. Results We propose a hybrid grid layout algorithm that consists of a non-grid, fast layout (preprocessor) algorithm and an approximate pattern matching algorithm that distributes the resultant preprocessed nodes on square grid points. To demonstrate the feasibility of the hybrid layout algorithm, it is characterized in terms of the calculation time, numbers of edge-edge and node-edge crossings, relative edge lengths, and F-measures. The proposed algorithm achieves outstanding performances compared with other existing grid layouts. Conclusions Use of an approximate pattern matching algorithm quickly redistributes the laid-out nodes by fast, non-grid algorithms on the square grid points, while preserving the topological relationships among the nodes. The proposed algorithm is a novel use of the pattern matching, thereby providing a breakthrough for grid layout. This application program can be freely downloaded from http://www.cadlive.jp/hybridlayout/hybridlayout.html. PMID:22679486

Application of approximate pattern matching in two dimensional spaces to grid layout for biochemical network maps.

PubMed

Inoue, Kentaro; Shimozono, Shinichi; Yoshida, Hideaki; Kurata, Hiroyuki

2012-01-01

For visualizing large-scale biochemical network maps, it is important to calculate the coordinates of molecular nodes quickly and to enhance the understanding or traceability of them. The grid layout is effective in drawing compact, orderly, balanced network maps with node label spaces, but existing grid layout algorithms often require a high computational cost because they have to consider complicated positional constraints through the entire optimization process. We propose a hybrid grid layout algorithm that consists of a non-grid, fast layout (preprocessor) algorithm and an approximate pattern matching algorithm that distributes the resultant preprocessed nodes on square grid points. To demonstrate the feasibility of the hybrid layout algorithm, it is characterized in terms of the calculation time, numbers of edge-edge and node-edge crossings, relative edge lengths, and F-measures. The proposed algorithm achieves outstanding performances compared with other existing grid layouts. Use of an approximate pattern matching algorithm quickly redistributes the laid-out nodes by fast, non-grid algorithms on the square grid points, while preserving the topological relationships among the nodes. The proposed algorithm is a novel use of the pattern matching, thereby providing a breakthrough for grid layout. This application program can be freely downloaded from http://www.cadlive.jp/hybridlayout/hybridlayout.html.

In vivo photoacoustic and ultrasonic mapping of rat sentinel lymph nodes with a modified commercial ultrasound imaging system

NASA Astrophysics Data System (ADS)

Erpelding, Todd N.; Kim, Chulhong; Pramanik, Manojit; Guo, Zijian; Dean, John; Jankovic, Ladislav; Maslov, Konstantin; Wang, Lihong V.

2010-02-01

Sentinel lymph node biopsy (SLNB) has become the standard method for axillary staging in breast cancer patients, relying on invasive identification of sentinel lymph nodes (SLNs) following injection of blue dye and radioactive tracers. While SLNB achieves a low false negative rate (5-10%), it is an invasive procedure requiring ionizing radiation. As an alternative to SLNB, ultrasound-guided fine needle aspiration biopsy has been tested clinically. However, ultrasound alone is unable to accurately identify which lymph nodes are sentinel. Therefore, a non-ionizing and noninvasive detection method for accurate SLN mapping is needed. In this study, we successfully imaged methylene blue dye accumulation in vivo in rat axillary lymph nodes using a Phillips iU22 ultrasound imaging system adapted for photoacoustic imaging with an Nd:YAG pumped, tunable dye laser. Photoacoustic images of rat SLNs clearly identify methylene blue dye accumulation within minutes following intradermal dye injection and co-registered photoacoustic/ultrasound images illustrate lymph node position relative to surrounding anatomy. To investigate clinical translation, the imaging depth was extended up to 2.5 cm by adding chicken breast tissue on top of the rat skin surface. These results raise confidence that photoacoustic imaging can be used clinically for accurate, noninvasive SLN mapping.

Function Allocation in a Robust Distributed Real-Time Environment

DTIC Science & Technology

1991-12-01

fundamental characteristic of a distributed system is its ability to map individual logical functions of an application program onto many physical nodes... how much of a node’s processor time is scheduled for function processing. IMC is the function- to -function communication required to facilitate...indicator of how much excess processor time a node has. The reconfiguration algorithms use these variables to determine the most appropriate node(s) to

A graph theoretic approach to scene matching

NASA Technical Reports Server (NTRS)

Ranganath, Heggere S.; Chipman, Laure J.

1991-01-01

The ability to match two scenes is a fundamental requirement in a variety of computer vision tasks. A graph theoretic approach to inexact scene matching is presented which is useful in dealing with problems due to imperfect image segmentation. A scene is described by a set of graphs, with nodes representing objects and arcs representing relationships between objects. Each node has a set of values representing the relations between pairs of objects, such as angle, adjacency, or distance. With this method of scene representation, the task in scene matching is to match two sets of graphs. Because of segmentation errors, variations in camera angle, illumination, and other conditions, an exact match between the sets of observed and stored graphs is usually not possible. In the developed approach, the problem is represented as an association graph, in which each node represents a possible mapping of an observed region to a stored object, and each arc represents the compatibility of two mappings. Nodes and arcs have weights indicating the merit or a region-object mapping and the degree of compatibility between two mappings. A match between the two graphs corresponds to a clique, or fully connected subgraph, in the association graph. The task is to find the clique that represents the best match. Fuzzy relaxation is used to update the node weights using the contextual information contained in the arcs and neighboring nodes. This simplifies the evaluation of cliques. A method of handling oversegmentation and undersegmentation problems is also presented. The approach is tested with a set of realistic images which exhibit many types of sementation errors.

Fluorescence spectroscopy using indocyanine green for lymph node mapping

NASA Astrophysics Data System (ADS)

Haj-Hosseini, Neda; Behm, Pascal; Shabo, Ivan; Wârdell, Karin

2014-02-01

The principles of cancer treatment has for years been radical resection of the primary tumor. In the oncologic surgeries where the affected cancer site is close to the lymphatic system, it is as important to detect the draining lymph nodes for metastasis (lymph node mapping). As a replacement for conventional radioactive labeling, indocyanine green (ICG) has shown successful results in lymph node mapping; however, most of the ICG fluorescence detection techniques developed are based on camera imaging. In this work, fluorescence spectroscopy using a fiber-optical probe was evaluated on a tissue-like ICG phantom with ICG concentrations of 6-64 μM and on breast tissue from five patients. Fiber-optical based spectroscopy was able to detect ICG fluorescence at low intensities; therefore, it is expected to increase the detection threshold of the conventional imaging systems when used intraoperatively. The probe allows spectral characterization of the fluorescence and navigation in the tissue as opposed to camera imaging which is limited to the view on the surface of the tissue.

Ultrafast and scalable cone-beam CT reconstruction using MapReduce in a cloud computing environment.

PubMed

Meng, Bowen; Pratx, Guillem; Xing, Lei

2011-12-01

Four-dimensional CT (4DCT) and cone beam CT (CBCT) are widely used in radiation therapy for accurate tumor target definition and localization. However, high-resolution and dynamic image reconstruction is computationally demanding because of the large amount of data processed. Efficient use of these imaging techniques in the clinic requires high-performance computing. The purpose of this work is to develop a novel ultrafast, scalable and reliable image reconstruction technique for 4D CBCT∕CT using a parallel computing framework called MapReduce. We show the utility of MapReduce for solving large-scale medical physics problems in a cloud computing environment. In this work, we accelerated the Feldcamp-Davis-Kress (FDK) algorithm by porting it to Hadoop, an open-source MapReduce implementation. Gated phases from a 4DCT scans were reconstructed independently. Following the MapReduce formalism, Map functions were used to filter and backproject subsets of projections, and Reduce function to aggregate those partial backprojection into the whole volume. MapReduce automatically parallelized the reconstruction process on a large cluster of computer nodes. As a validation, reconstruction of a digital phantom and an acquired CatPhan 600 phantom was performed on a commercial cloud computing environment using the proposed 4D CBCT∕CT reconstruction algorithm. Speedup of reconstruction time is found to be roughly linear with the number of nodes employed. For instance, greater than 10 times speedup was achieved using 200 nodes for all cases, compared to the same code executed on a single machine. Without modifying the code, faster reconstruction is readily achievable by allocating more nodes in the cloud computing environment. Root mean square error between the images obtained using MapReduce and a single-threaded reference implementation was on the order of 10(-7). Our study also proved that cloud computing with MapReduce is fault tolerant: the reconstruction completed successfully with identical results even when half of the nodes were manually terminated in the middle of the process. An ultrafast, reliable and scalable 4D CBCT∕CT reconstruction method was developed using the MapReduce framework. Unlike other parallel computing approaches, the parallelization and speedup required little modification of the original reconstruction code. MapReduce provides an efficient and fault tolerant means of solving large-scale computing problems in a cloud computing environment.

Ultrafast and scalable cone-beam CT reconstruction using MapReduce in a cloud computing environment

PubMed Central

Meng, Bowen; Pratx, Guillem; Xing, Lei

2011-01-01

Purpose: Four-dimensional CT (4DCT) and cone beam CT (CBCT) are widely used in radiation therapy for accurate tumor target definition and localization. However, high-resolution and dynamic image reconstruction is computationally demanding because of the large amount of data processed. Efficient use of these imaging techniques in the clinic requires high-performance computing. The purpose of this work is to develop a novel ultrafast, scalable and reliable image reconstruction technique for 4D CBCT/CT using a parallel computing framework called MapReduce. We show the utility of MapReduce for solving large-scale medical physics problems in a cloud computing environment. Methods: In this work, we accelerated the Feldcamp–Davis–Kress (FDK) algorithm by porting it to Hadoop, an open-source MapReduce implementation. Gated phases from a 4DCT scans were reconstructed independently. Following the MapReduce formalism, Map functions were used to filter and backproject subsets of projections, and Reduce function to aggregate those partial backprojection into the whole volume. MapReduce automatically parallelized the reconstruction process on a large cluster of computer nodes. As a validation, reconstruction of a digital phantom and an acquired CatPhan 600 phantom was performed on a commercial cloud computing environment using the proposed 4D CBCT/CT reconstruction algorithm. Results: Speedup of reconstruction time is found to be roughly linear with the number of nodes employed. For instance, greater than 10 times speedup was achieved using 200 nodes for all cases, compared to the same code executed on a single machine. Without modifying the code, faster reconstruction is readily achievable by allocating more nodes in the cloud computing environment. Root mean square error between the images obtained using MapReduce and a single-threaded reference implementation was on the order of 10−7. Our study also proved that cloud computing with MapReduce is fault tolerant: the reconstruction completed successfully with identical results even when half of the nodes were manually terminated in the middle of the process. Conclusions: An ultrafast, reliable and scalable 4D CBCT/CT reconstruction method was developed using the MapReduce framework. Unlike other parallel computing approaches, the parallelization and speedup required little modification of the original reconstruction code. MapReduce provides an efficient and fault tolerant means of solving large-scale computing problems in a cloud computing environment. PMID:22149842

Intraoperative sentinel node identification in early stage cervical cancer using a combination of radiolabeled albumin injection and isosulfan blue dye injection.

PubMed

Martínez-Palones, José M; Gil-Moreno, Antonio; Pérez-Benavente, María A; Roca, Isabel; Xercavins, Jordi

2004-03-01

We investigated the feasibility of sentinel lymph node identification using radioisotopic lymphatic mapping with technetium-99m-labeled human serum albumin and isosulfan blue dye injection in patients undergoing radical hysterectomy with pelvic lymphadenectomy for treatment of early cervical cancer. Between September 2000 and October 2002, 25 patients with cervical cancer FIGO stage I (n=24) or stage II (n=1) underwent sentinel lymph node detection with preoperative lymphoscintigraphy (technetium-99m colloid albumin injection around the tumor) and intraoperative lymphatic mapping with blue dye and a handheld or laparoscopic gamma probe. Complete pelvic or paraaortic lymphadenectomy was performed in all cases by open surgery or laparoscopic surgery. In 23 evaluable patients, a total of 51 sentinel lymph nodes were detected by lymphoscintigraphy (mean 2.21 nodes per patient). Intraoperatively, 61 sentinel lymph nodes were identified, with a mean of 2.52 nodes per patient by gamma probe and a mean of 1.94 nodes per patient after isosulfan blue injection. Forty percent of sentinel nodes were found in the interiliac region and 25% in the external iliac area. Microscopic nodal metastases (four nodes) were confirmed in 12% of cases. All these lymph nodes were previously detected as sentinel lymph nodes. The remaining 419 nodes after pelvic lymphadenectomy were histologically negative. Sentinel lymph node identification with technetium-99m-labeled nanocolloid combined with blue dye injection is feasible and showed a 100% negative predictive value, and potentially identified women in whom lymph node dissection can be avoided.

Multifunctional Polymer Microbubbles for Advanced Sentinel Lymph Node Imaging and Mapping

DTIC Science & Technology

2012-03-01

undesired PMA attached to microbubble surface. Figure 1: One-pot polymer -lipid microbubbles. (a) Synthesis of thiolated poly(acrylic acid) with...Award Number: W81XWH-11-1-0215 TITLE: Multifunctional Polymer Microbubbles for Advanced Sentinel...February 2012 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Multifunctional Polymer Microbubbles for Advanced Sentinel Lymph Node Imaging and Mapping 5b

Sentinel lymph node mapping in endometrial cancer: a systematic review and meta-analysis.

PubMed

Lin, Hefeng; Ding, Zheyuan; Kota, Vishnu Goutham; Zhang, Xiaoming; Zhou, Jianwei

2017-07-11

Endometrial cancer is the most frequent tumor in the female reproductive system, while the sentinel lymph node (SLN) mapping for diagnostic efficacy of endometrial cancer is still controversial. This meta-analysis was conducted to evaluate the diagnostic value of SLN in the assessment of lymph nodal involvement in endometrial cancer. Forty-four studies including 2,236 cases were identified. The pooled overall detection rate was 83% (95% CI: 80-86%). The pooled sensitivity was 91% (95% CI: 87-95%). The bilateral pelvic node detection rate was 56% (95% CI: 48-64%). Use of indocyanine green (ICG) increased the overall detection rate to 93% (95% CI: 89-96%) and robotic-assisted surgery also increased the overall detection rate to 86% (95% CI: 79-93%). In summary, our meta-analysis provides strong evidence that sentinel node mapping is an accurate and feasible method that performs well diagnostically for the assessment of lymph nodal involvement in endometrial cancer. Cervical injection, robot-assisted surgery, as well as using ICG, optimized the sensitivity and detection rate of the technique. Sentinel lymph mapping may potentially leading to a greater utilization by gynecologic surgeons in the future.

A quantitative approach to measure road network information based on edge diversity

NASA Astrophysics Data System (ADS)

Wu, Xun; Zhang, Hong; Lan, Tian; Cao, Weiwei; He, Jing

2015-12-01

The measure of map information has been one of the key issues in assessing cartographic quality and map generalization algorithms. It is also important for developing efficient approaches to transfer geospatial information. Road network is the most common linear object in real world. Approximately describe road network information will benefit road map generalization, navigation map production and urban planning. Most of current approaches focused on node diversities and supposed that all the edges are the same, which is inconsistent to real-life condition, and thus show limitations in measuring network information. As real-life traffic flow are directed and of different quantities, the original undirected vector road map was first converted to a directed topographic connectivity map. Then in consideration of preferential attachment in complex network study and rich-club phenomenon in social network, the from and to weights of each edge are assigned. The from weight of a given edge is defined as the connectivity of its end node to the sum of the connectivities of all the neighbors of the from nodes of the edge. After getting the from and to weights of each edge, edge information, node information and the whole network structure information entropies could be obtained based on information theory. The approach has been applied to several 1 square mile road network samples. Results show that information entropies based on edge diversities could successfully describe the structural differences of road networks. This approach is a complementarity to current map information measurements, and can be extended to measure other kinds of geographical objects.

Efficient algorithms for dilated mappings of binary trees

NASA Technical Reports Server (NTRS)

Iqbal, M. Ashraf

1990-01-01

The problem is addressed to find a 1-1 mapping of the vertices of a binary tree onto those of a target binary tree such that the son of a node on the first binary tree is mapped onto a descendent of the image of that node in the second binary tree. There are two natural measures of the cost of this mapping, namely the dilation cost, i.e., the maximum distance in the target binary tree between the images of vertices that are adjacent in the original tree. The other measure, expansion cost, is defined as the number of extra nodes/edges to be added to the target binary tree in order to ensure a 1-1 mapping. An efficient algorithm to find a mapping of one binary tree onto another is described. It is shown that it is possible to minimize one cost of mapping at the expense of the other. This problem arises when designing pipelined arithmetic logic units (ALU) for special purpose computers. The pipeline is composed of ALU chips connected in the form of a binary tree. The operands to the pipeline can be supplied to the leaf nodes of the binary tree which then process and pass the results up to their parents. The final result is available at the root. As each new application may require a distinct nesting of operations, it is useful to be able to find a good mapping of a new binary tree over existing ALU tree. Another problem arises if every distinct required binary tree is known beforehand. Here it is useful to hardwire the pipeline in the form of a minimal supertree that contains all required binary trees.

[Role of sentinel lymph nodes and lymphatic mapping of colorectal cancer].

PubMed

Ivanov, K; Kolev, N; Ignatov, V; Temelkov, T; Madzhov, R

2005-01-01

The accuracy of staging of colorectal cancer is dependable of number of lymph nodes, colected and investegated from the pathologist. Moreover 50% of newfounded cases with colorectal cancer are diagnosed as I or II stage of the desease. Between 15% and 20% of these patients develop regional or distant metastases around 5 years after the examination, despite of the radical surgery. This may be due to pathological "understaging" (decrease of the stage), becouse of missed micrometastases, which size often is smaller than 5 mm. High accurate and specific pathologoanatomical methods for "ultrastaging" are cost-expensive, therefore their selective application to labeled sentinel lymph nodes has a economical benefit and saves a time. Moreover it is decreasing the understaging effect, assosiated with convectional pathologoanatomical investigaton. In the future, the technical progress will develop the intensive competiton between the sentinel lymph node mapping and the improved imaging diagnostic techniques as flurodeoxyglucose (18FDG), positron emision tomography (PET), or the other molecular imaging techniques. Unfortunately, the limited spatial resolution of these techniques, do not allow to be used for tumor staging as sentinel lymph node techniques. Therefore the sentinel lymphnode mapping become the choice of the lymphnode staging technique.

Mapping to Irregular Torus Topologies and Other Techniques for Petascale Biomolecular Simulation

PubMed Central

Phillips, James C.; Sun, Yanhua; Jain, Nikhil; Bohm, Eric J.; Kalé, Laxmikant V.

2014-01-01

Currently deployed petascale supercomputers typically use toroidal network topologies in three or more dimensions. While these networks perform well for topology-agnostic codes on a few thousand nodes, leadership machines with 20,000 nodes require topology awareness to avoid network contention for communication-intensive codes. Topology adaptation is complicated by irregular node allocation shapes and holes due to dedicated input/output nodes or hardware failure. In the context of the popular molecular dynamics program NAMD, we present methods for mapping a periodic 3-D grid of fixed-size spatial decomposition domains to 3-D Cray Gemini and 5-D IBM Blue Gene/Q toroidal networks to enable hundred-million atom full machine simulations, and to similarly partition node allocations into compact domains for smaller simulations using multiple-copy algorithms. Additional enabling techniques are discussed and performance is reported for NCSA Blue Waters, ORNL Titan, ANL Mira, TACC Stampede, and NERSC Edison. PMID:25594075

Saliency Detection via Absorbing Markov Chain With Learnt Transition Probability.

PubMed

Lihe Zhang; Jianwu Ai; Bowen Jiang; Huchuan Lu; Xiukui Li

2018-02-01

In this paper, we propose a bottom-up saliency model based on absorbing Markov chain (AMC). First, a sparsely connected graph is constructed to capture the local context information of each node. All image boundary nodes and other nodes are, respectively, treated as the absorbing nodes and transient nodes in the absorbing Markov chain. Then, the expected number of times from each transient node to all other transient nodes can be used to represent the saliency value of this node. The absorbed time depends on the weights on the path and their spatial coordinates, which are completely encoded in the transition probability matrix. Considering the importance of this matrix, we adopt different hierarchies of deep features extracted from fully convolutional networks and learn a transition probability matrix, which is called learnt transition probability matrix. Although the performance is significantly promoted, salient objects are not uniformly highlighted very well. To solve this problem, an angular embedding technique is investigated to refine the saliency results. Based on pairwise local orderings, which are produced by the saliency maps of AMC and boundary maps, we rearrange the global orderings (saliency value) of all nodes. Extensive experiments demonstrate that the proposed algorithm outperforms the state-of-the-art methods on six publicly available benchmark data sets.

Scanning elastic scattering spectroscopy detects metastatic breast cancer in sentinel lymph nodes

NASA Astrophysics Data System (ADS)

Austwick, Martin R.; Clark, Benjamin; Mosse, Charles A.; Johnson, Kristie; Chicken, D. Wayne; Somasundaram, Santosh K.; Calabro, Katherine W.; Zhu, Ying; Falzon, Mary; Kocjan, Gabrijela; Fearn, Tom; Bown, Stephen G.; Bigio, Irving J.; Keshtgar, Mohammed R. S.

2010-07-01

A novel method for rapidly detecting metastatic breast cancer within excised sentinel lymph node(s) of the axilla is presented. Elastic scattering spectroscopy (ESS) is a point-contact technique that collects broadband optical spectra sensitive to absorption and scattering within the tissue. A statistical discrimination algorithm was generated from a training set of nearly 3000 clinical spectra and used to test clinical spectra collected from an independent set of nodes. Freshly excised nodes were bivalved and mounted under a fiber-optic plate. Stepper motors raster-scanned a fiber-optic probe over the plate to interrogate the node's cut surface, creating a 20×20 grid of spectra. These spectra were analyzed to create a map of cancer risk across the node surface. Rules were developed to convert these maps to a prediction for the presence of cancer in the node. Using these analyses, a leave-one-out cross-validation to optimize discrimination parameters on 128 scanned nodes gave a sensitivity of 69% for detection of clinically relevant metastases (71% for macrometastases) and a specificity of 96%, comparable to literature results for touch imprint cytology, a standard technique for intraoperative diagnosis. ESS has the advantage of not requiring a pathologist to review the tissue sample.

Laparoscopic Sentinel Node Mapping in Endometrial Cancer After Hysteroscopic Injection of Indocyanine Green.

PubMed

Martinelli, Fabio; Ditto, Antonino; Bogani, Giorgio; Signorelli, Mauro; Chiappa, Valentina; Lorusso, Domenica; Haeusler, Edward; Raspagliesi, Francesco

2017-01-01

To report the detection rate (DR) of sentinel lymph nodes (SLNs) in endometrial cancer (EC) patients after hysteroscopic injection of indocyanine green (ICG) and laparoscopic near-infrared (L-NIR) fluorescence mapping. Prospectively collected data (Canadian Task Force classification II-2). Gynecologic oncology referral center. Consecutive patients with apparent early-stage endometrioid EC scheduled for surgical treatment: total laparoscopic hysterectomy, bilateral salpingo-oophorectomy, SLN mapping. The mapping technique consisted in an intraoperative hysteroscopic peritumoral injection of 5 mg ICG followed by L-NIR fluorescence mapping. Evaluations of the SLN DR and sites of mapping were performed. A total of 57 procedures was performed. Patient mean age was 60 years (range, 28-80) and mean body mass index was 28.2 kg/m 2 (range, 19-43). At least 1 SLN was detected in 89.5% of the whole population (51/57). After the first 16 cases, L-NIR camera technical improvement led to a 95% DR (39/41). The mean number of harvested SLNs was 4.1 (range. 1-8), and in 47% of cases SLNs mapped to aortic nodes (24/51). Bilateral pelvic mapping was found in 74.5% of cases (38/51). Three patients had SLN metastases: 1 in the pelvic area only, 1 both in the pelvic and aortic area, and 1 presented with 2 metastatic aortic SLNs with negative pelvic SLNs. Overall, 2 of 3 node-positive patients (67%) had aortic SLN involvement. No adverse events were reported. Laparoscopic SLN mapping after the hysteroscopic injection of ICG has comparable DRs with both radioactive tracer series and ICG series with cervical injection, overcoming the need for radioactive substances. Hysteroscopic injection leads to a higher mapping in the aortic area compared with cervical injection. Further investigation is warranted on this topic. Copyright © 2016 AAGL. Published by Elsevier Inc. All rights reserved.

Sentinel node detection in cervical cancer with (99m)Tc-phytate.

PubMed

Silva, Lucas B; Silva-Filho, Agnaldo L; Traiman, Paulo; Triginelli, Sérgio A; de Lima, Carla Flávia; Siqueira, Cristiano Ferrari; Barroso, Adelanir; Rossi, Telma Maria F F; Pedrosa, Moises Salgado; Miranda, Dairton; Melo, José Renan Cunha

2005-05-01

The aim of this study was to investigate the feasibility of sentinel lymph node (SLN) identification using radioisotopic lymphatic mapping with technetium-99 m-labeled phytate in patients undergoing radical hysterectomy with pelvic lymphadenectomy for treatment of early cervical cancer. Between July 2001 and February 2003, 56 patients with cervical cancer FIGO stage I (n = 53) or stage II (n = 3) underwent sentinel lymph node detection with preoperative lymphoscintigraphy ((99m)Tc-labeled phytate injected into the uterine cervix, at 3, 6, 9, and 12 o'clock, at a dose of 55-74 MBq in a volume of 0.8 ml) and intraoperative lymphatic mapping with a handheld gamma probe. Radical hysterectomy was aborted in three cases because parametrial invasion was found intraoperatively and we performed only sentinel node resection. The remaining 53 patients underwent radical hysterectomy with complete pelvic lymphadenectomy. Sentinel nodes were detected using a handheld gamma-probe and removed for pathological assessment during the abdominal radical hysterectomy and pelvic lymphadenectomy. One or more sentinel nodes were detected in 52 out of 56 eligible patients (92.8%). A total of 120 SLNs were detected by lymphoscintigraphy (mean 2.27 nodes per patient) and intraoperatively by gamma probe. Forty-four percent of SLNs were found in the external iliac area, 39% in the obturator region, 8.3% in interiliac region, and 6.7% in the common iliac area. Unilateral sentinel nodes were found in thirty-one patients (59%). The remaining 21 patients (41%) had bilateral sentinel nodes. Microscopic nodal metastases were confirmed in 17 (32%) cases. In 10 of these patients, only SLNs had metastases. The 98 sentinel nodes that were negative on hematoxylin and eosin were submitted to cytokeratin immunohistochemical analysis. Five (5.1%) micrometastases were identified with this technique. The sensitivity of the sentinel node was 82.3% (CI 95% = 56.6-96.2) and the negative predictive value was 92.1% (CI 95% = 78.6-98.3). The accuracy of sentinel node in predicting the lymph node status was 94.2%. Preoperative lymphoscintigraphy and intraoperative lymphatic mapping with (99m)Tc-labeled phytate are effective in identifying sentinel nodes in patients undergoing radical hysterectomy and to select women in whom lymph node dissection can be avoided.

Factors controlling nanoparticle pharmacokinetics: an integrated analysis and perspective.

PubMed

Moghimi, S M; Hunter, A C; Andresen, T L

2012-01-01

Intravenously injected nanoparticulate drug carriers provide a wide range of unique opportunities for site-specific targeting of therapeutic agents to many areas within the vasculature and beyond. Pharmacokinetics and biodistribution of these carriers are controlled by a complex array of interrelated core and interfacial physicochemical and biological factors. Pertinent to realizing therapeutic goals, definitive maps that establish the interdependency of nanoparticle size, shape, and surface characteristics in relation to interfacial forces, biodistribution, controlled drug release, excretion, and adverse effects must be outlined. These concepts are critically evaluated and an integrated perspective is provided on the basis of the recent application of nanoscience approaches to nanocarrier design and engineering. The future of this exciting field is bright; some regulatory-approved products are already on the market and many are in late-phase clinical trials. With concomitant advances in extensive computational knowledge of the genomics and epigenomics of interindividual variations in drug responses, the boundaries toward development of personalized nanomedicines can be pushed further.

The efficacy of sentinel lymph node mapping with indocyanine green in cervical cancer.

PubMed

Kim, Ju-Hyun; Kim, Dae-Yeon; Suh, Dae-Shik; Kim, Jong-Hyeok; Kim, Yong-Man; Kim, Young-Tak; Nam, Joo-Hyun

2018-03-09

Lymph node metastasis is a significant predictive factor for disease recurrence and survival in cervical cancer patients. Given the importance of lymph node metastasis, it is imperative that patients harboring metastasis are identified and can undergo appropriate treatment. Sentinel lymph node (SLN) mapping has drawn attention as a lymph node mapping technique. We evaluated the feasibility and efficacy of (SLN) mapping using indocyanine green (ICG) in cervical cancer. We performed a single-center, retrospective study of 103 surgically treated cervical cancer patients who underwent SLN mapping. After using ICG to detect SLN during surgery, we removed the SLNs followed by laparoscopic or robotic-assisted radical surgery and bilateral pelvic lymphadenectomy. Stage IB1 was the most common (61.17%). At least one SLN was detected in all cases. Eighty-eight patients (85.44%) had bilateral pelvic SLNs. The mean number of SLN per patient was 2.34. The side-specific sensitivity was 71.43%, the specificity was 100%, the negative predictive value (NPV) was 93.98%, and the false negative rate (FNR) was 28.57%. In cases of tumors smaller than 2 cm with negative lymph node metastasis on imaging, the study revealed a side-specific sensitivity of 100%, a specificity of 100%, a NPV of 100%, and a FNR of 0%. Large tumor size (≥ 4 cm), a previous history of a loop electrosurgical excision procedure (LEEP), depth of invasion (≥ 50%), the microscopic parametrial (PM) invasion, and vaginal extension were significantly associated with the false-negative detection of SLN. Moreover, the microscopic PM invasion was the only risk factor of the false-negative detection of SLN in multivariate analysis. SLN mapping with ICG in cervical cancer is feasible and has high detection rate. The sensitivity of 100% was high enough to perform SLN biopsy alone in an early stage in which the tumor is less than 2 cm, with no lymphadenopathy on image examination. However, for large or invasive tumors, we would have to be cautious about performing SLN biopsy alone. Retrospectively registered 2017-0600.

Lymphatic Mapping and Sentinel Lymph Node Biopsy in Women With Squamous Cell Carcinoma of the Vulva: A Gynecologic Oncology Group Study

PubMed Central

Levenback, Charles F.; Ali, Shamshad; Coleman, Robert L.; Gold, Michael A.; Fowler, Jeffrey M.; Judson, Patricia L.; Bell, Maria C.; De Geest, Koen; Spirtos, Nick M.; Potkul, Ronald K.; Leitao, Mario M.; Bakkum-Gamez, Jamie N.; Rossi, Emma C.; Lentz, Samuel S.; Burke, James J.; Van Le, Linda; Trimble, Cornelia L.

2012-01-01

Purpose To determine the safety of sentinel lymph node biopsy as a replacement for inguinal femoral lymphadenectomy in selected women with vulvar cancer. Patients and Methods Eligible women had squamous cell carcinoma, at least 1-mm invasion, and tumor size ≥ 2 cm and ≤ 6 cm. The primary tumor was limited to the vulva, and there were no groin lymph nodes that were clinically suggestive of cancer. All women underwent intraoperative lymphatic mapping, sentinel lymph node biopsy, and inguinal femoral lymphadenectomy. Histologic ultra staging of the sentinel lymph node was prescribed. Results In all, 452 women underwent the planned procedures, and 418 had at least one sentinel lymph node identified. There were 132 node-positive women, including 11 (8.3%) with false-negative nodes. Twenty-three percent of the true-positive patients were detected by immunohistochemical analysis of the sentinel lymph node. The sensitivity was 91.7% (90% lower confidence bound, 86.7%) and the false-negative predictive value (1-negative predictive value) was 3.7% (90% upper confidence bound, 6.1%). In women with tumor less than 4 cm, the false-negative predictive value was 2.0% (90% upper confidence bound, 4.5%). Conclusion Sentinel lymph node biopsy is a reasonable alternative to inguinal femoral lymphadenectomy in selected women with squamous cell carcinoma of the vulva. PMID:22753905

Sentinel Lymph Node Biopsy for Cutaneous Head and Neck Melanoma: Mapping the Parotid Gland.

PubMed

Picon, Antonio I; Coit, Daniel G; Shaha, Ashok R; Brady, Mary S; Boyle, Jay O; Singh, Bhuvanesh B; Wong, Richard J; Busam, Klaus J; Shah, Jatin P; Kraus, Dennis H

2016-12-01

Sentinel lymph node biopsy (SLNB) for primary cutaneous head and neck melanoma (CHNM) has been shown to be successful and is the current standard of care for intermediate-thickness melanoma. We evaluated our experience with CHNM associated with SLNB mapping to the region of the parotid gland. Retrospective review of a prospectively collected melanoma database identified 1014 CHNMs. Two-hundred twenty-three patients underwent SLNB, and 72 (32%) had mapping in the region of the parotid gland between May 1995 and June 2003. The mean number of SLNs per patient was 2.5. A sentinel lymph node (SLN) was successfully identified in 94% of patients, and in 12%, the SLN was positive for metastatic disease. Biopsy of intraparotid SLNs was performed in 51.4% and of periparotid SLNs in 26.4%, and a superficial parotidectomy was performed in 22.2%. Ten patients were found to have lymph nodes in the parotid region with metastatic disease (eight identified by SLNB), and two (20%) patients developed intraparotid lymph node recurrence in the setting of a negative SLNB. Same-basin recurrence in SLN-negative patients was 3.3% with a median follow-up of 26 months. Facial nerve dysfunction was identified in seven (10%) patients. Facial nerve function returned to preoperative status in all patients. SLNB for patients with primary CHNM mapping to the parotid gland can be performed with a high degree of accuracy and a low morbidity consisting of temporary facial nerve paresis.

A pilot study to assess near infrared laparoscopy with indocyanine green (ICG) for intraoperative sentinel lymph node mapping in early colon cancer.

PubMed

Currie, A C; Brigic, A; Thomas-Gibson, S; Suzuki, N; Moorghen, M; Jenkins, J T; Faiz, O D; Kennedy, R H

2017-11-01

Previous attempts at sentinel lymph node (SLN) mapping in colon cancer have been compromised by ineffective tracers and the inclusion of advanced disease. This study evaluated the feasibility of fluorescence detection of SLNs with indocyanine green (ICG) for lymphatic mapping in T1/T2 clinically staged colonic malignancy. Consecutive patients with clinical T1/T2 stage colon cancer underwent endoscopic peritumoral submucosal injection of indocyanine green (ICG) for fluorescence detection of SLN using a near-infrared (NIR) camera. All patients underwent laparoscopic complete mesocolic excision surgery. Detection rate and sensitivity of the NIR-ICG technique were the study endpoints. Thirty patients mean age = 68 years [range = 38-80], mean BMI = 26.2 (IQR = 24.7-28.6) were studied. Mesocolic sentinel nodes (median = 3/patient) were detected by fluorescence within the standard resection field in 27/30 patients. Overall, ten patients had lymph node metastases, with one of these patients having a failed SLN procedure. Of the 27 patients with completed SLN mapping, nine patients had histologically positive lymph nodes containing malignancy. 3/9 had positive SLNs with 6 false negatives. In five of these false negative patients, tumours were larger than 35 mm with four also being T3/T4. ICG mapping with NIR fluorescence allowed mesenteric detection of SLNs in clinical T1/T2 stage colonic cancer. CLINICALTRIALS.GOV: ID: NCT01662752. Copyright © 2017 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

SpicyNodes Radial Map Engine

NASA Astrophysics Data System (ADS)

Douma, M.; Ligierko, G.; Angelov, I.

2008-10-01

The need for information has increased exponentially over the past decades. The current systems for constructing, exploring, classifying, organizing, and searching information face the growing challenge of enabling their users to operate efficiently and intuitively in knowledge-heavy environments. This paper presents SpicyNodes, an advanced user interface for difficult interaction contexts. It is based on an underlying structure known as a radial map, which allows users to manipulate and interact in a natural manner with entities called nodes. This technology overcomes certain limitations of existing solutions and solves the problem of browsing complex sets of linked information. SpicyNodes is also an organic system that projects users into a living space, stimulating exploratory behavior and fostering creative thought. Our interactive radial layout is used for educational purposes and has the potential for numerous other applications.

Meta-analysis of aberrant lymphatic drainage in recurrent breast cancer.

PubMed

Ahmed, M; Baker, R; Rubio, I T

2016-11-01

Sentinel node biopsy (SNB) in recurrent breast cancer offers targeted axillary staging compared with axillary lymph node dissection (ALND) or no treatment. The evidence for lymphatic mapping in recurrent breast cancer is reviewed, focusing on aberrant drainage and its implications for patient management. A meta-analysis of studies evaluating lymphatic mapping in recurrent breast cancer was performed. Outcomes included sentinel node identification, aberrant lymphatic pathways and metastatic node rates in aberrant drainage and ipsilateral axilla. Pooled odds ratios (ORs) and 95 per cent confidence intervals (c.i.) were estimated using fixed-effect analyses, or random-effects analyses in the event of statistically significant heterogeneity. Seven studies reported data on lymphatic mapping in 1053 patients with recurrent breast cancer. The intraoperative sentinel node identification rate was 59·6 (95 per cent c.i. 56·7 to 62·6) per cent, and significantly greater when the original axillary surgery was SNB compared with ALND (OR 2·97, 95 per cent c.i. 1·66 to 5·32). The rate of aberrant lymphatic drainage identification was 25·7 (23·0 to 28·3) per cent, and significantly greater when the original axillary surgery was ALND (OR 0·27, 0·19 to 0·38). The metastatic sentinel node rate was 10·4 (8·6 to 12·3) per cent, and a significantly greater metastatic nodal burden was identified in the ipsilateral axilla (OR 6·31, 1·03 to 38·79). Lymphatic mapping is feasible in recurrent breast cancer. It avoids ALND in over 50 per cent of patients who have undergone SNB, and allows the 4 per cent of patients with metastatically involved aberrant nodes to receive targeted surgical and adjuvant therapies. © 2016 BJS Society Ltd Published by John Wiley & Sons Ltd.

FIGO stage IIIC endometrial cancer identification among patients with complex atypical hyperplasia, grade 1 and 2 endometrioid endometrial cancer: laparoscopic indocyanine green sentinel lymph node mapping versus frozen section of the uterus, why get around the problem?

PubMed

Papadia, Andrea; Gasparri, Maria Luisa; Siegenthaler, Franziska; Imboden, Sara; Mohr, Stefan; Mueller, Michael D

2017-03-01

To compare two surgical strategies used to identify lymph node metastases in patients with preoperative diagnosis of complex atypical hyperplasia (CAH), grade 1 and 2 endometrial cancer (EC). Data on patients with preoperative diagnosis of CAH, grade 1 and 2 EC undergoing laparoscopic indocyanine green (ICG) sentinel lymph node (SLN) mapping followed by frozen section of the uterus were collected. When risk factors were identified at frozen section, patients were subjected to a systematic lymphadenectomy. False negative (FN) rates, negative predictive values (NPV), positive predictive values (PPV) and correlation with stage IIIC EC were calculated for the systematic lymphadenectomy based on frozen section of the uterus and for the SLN mapping. Six (9.5%) out of 63 patients had lymph nodal metastases. Based on frozen section of the uterus, 22 (34.9%) and 15 (22.2%) patients underwent a pelvic and a pelvic and paraaortic lymphadenectomy, respectively. Five patients with stage IIIC disease were identified with a FN rate of 16.7% and a NPV and PPV of 97.6 and 27.3%, respectively. Overall and bilateral detection rates of ICG SLN mapping were 100 and 97.6%, respectively; no FN were recorded. The identification of patients with stage IIIC disease with ICG SLN mapping showed a NPV and PPV of 100%. Correlation between indication to lymphadenectomy and stage IIIC disease was poor (κ = 0.244) when based on frozen section of the uterus and excellent (κ = 1) when based on SLN mapping. ICG SLN mapping reduces the number of unnecessary systematic lymphadenectomies and the risk of underdiagnosing patients with metastatic lymph nodes.

Multifunctional Polymer Microbubbles for Advanced Sentinel Lymph Node Imaging and Mapping

DTIC Science & Technology

2012-06-01

of thiolated poly(acrylic acid) with fluorescein attached. (b) Bright field image of large bubbles stabilized by polymer and phospholipid...Page 1 of 6 AD_________________ Award Number: W81XWH-11-1-0215 TITLE:   Multifunctional Polymer Microbubbles for Advanced... Polymer Microbubbles for Advanced Sentinel Lymph Node Imaging and Mapping 5b. GRANT NUMBER W81XWH-11-1-0215   5c. PROGRAM ELEMENT NUMBER 6

Sentinel lymph node accumulation of Lymphoseek and Tc-99m-sulfur colloid using a “2-day” protocol☆

PubMed Central

Wallace, Anne M.; Hoh, Carl K.; Limmer, Karl K.; Darrah, Denise D.; Schulteis, Gery; Vera, David R.

2014-01-01

Lymphoseek is a receptor-binding radiopharmaceutical specifically designed for sentinel lymph node (SLN) mapping. We conducted a clinical trial which measured the injection site clearance and sentinel lymph node accumulation after a single intradermal injection of Lymphoseek or unfiltered [99mTc]sulfur colloid (TcSC) using a “2-day” protocol for SLN mapping of breast cancer. Eleven patients with breast cancer participated in this study. Five patients received an intradermal administration of 1.0 nmol of 99mTc-labeled Lymphoseek; SLN mapping was performed on four subjects within 19 to 27 h. Six subjects received an intradermal administration of TcSC; SLN mapping was performed on five subjects within 18 to 26 h. Lymphoseek exhibited a significantly (P<.001) faster injection site clearance than TcSC. The mean Lymphoseek clearance half-time was 2.18±1.09 h compared to 57.4±92.8 h for TcSC. The mean sentinel lymph node uptake of Lymphoseek (1.5±1.7%) and TcSC (3.5±3.1%) was statistically equivalent (P=.213). When an intradermal injection is employed, Lymphoseek demonstrated faster injection site clearance than unfiltered [99mTc]sulfur colloid and persistent SLN accumulation for at least 24 h. PMID:19647175

Monte Carlo simulation of photon migration in a cloud computing environment with MapReduce

PubMed Central

Pratx, Guillem; Xing, Lei

2011-01-01

Monte Carlo simulation is considered the most reliable method for modeling photon migration in heterogeneous media. However, its widespread use is hindered by the high computational cost. The purpose of this work is to report on our implementation of a simple MapReduce method for performing fault-tolerant Monte Carlo computations in a massively-parallel cloud computing environment. We ported the MC321 Monte Carlo package to Hadoop, an open-source MapReduce framework. In this implementation, Map tasks compute photon histories in parallel while a Reduce task scores photon absorption. The distributed implementation was evaluated on a commercial compute cloud. The simulation time was found to be linearly dependent on the number of photons and inversely proportional to the number of nodes. For a cluster size of 240 nodes, the simulation of 100 billion photon histories took 22 min, a 1258 × speed-up compared to the single-threaded Monte Carlo program. The overall computational throughput was 85,178 photon histories per node per second, with a latency of 100 s. The distributed simulation produced the same output as the original implementation and was resilient to hardware failure: the correctness of the simulation was unaffected by the shutdown of 50% of the nodes. PMID:22191916

Accurate Analysis of the Change in Volume, Location, and Shape of Metastatic Cervical Lymph Nodes During Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takao, Seishin, E-mail: takao@mech-me.eng.hokudai.ac.jp; Tadano, Shigeru; Taguchi, Hiroshi

2011-11-01

Purpose: To establish a method for the accurate acquisition and analysis of the variations in tumor volume, location, and three-dimensional (3D) shape of tumors during radiotherapy in the era of image-guided radiotherapy. Methods and Materials: Finite element models of lymph nodes were developed based on computed tomography (CT) images taken before the start of treatment and every week during the treatment period. A surface geometry map with a volumetric scale was adopted and used for the analysis. Six metastatic cervical lymph nodes, 3.5 to 55.1 cm{sup 3} before treatment, in 6 patients with head and neck carcinomas were analyzed inmore » this study. Three fiducial markers implanted in mouthpieces were used for the fusion of CT images. Changes in the location of the lymph nodes were measured on the basis of these fiducial markers. Results: The surface geometry maps showed convex regions in red and concave regions in blue to ensure that the characteristics of the 3D tumor geometries are simply understood visually. After the irradiation of 66 to 70 Gy in 2 Gy daily doses, the patterns of the colors had not changed significantly, and the maps before and during treatment were strongly correlated (average correlation coefficient was 0.808), suggesting that the tumors shrank uniformly, maintaining the original characteristics of the shapes in all 6 patients. The movement of the gravitational center of the lymph nodes during the treatment period was everywhere less than {+-}5 mm except in 1 patient, in whom the change reached nearly 10 mm. Conclusions: The surface geometry map was useful for an accurate evaluation of the changes in volume and 3D shapes of metastatic lymph nodes. The fusion of the initial and follow-up CT images based on fiducial markers enabled an analysis of changes in the location of the targets. Metastatic cervical lymph nodes in patients were suggested to decrease in size without significant changes in the 3D shape during radiotherapy. The movements of the gravitational center of the lymph nodes were almost all less than {+-}5 mm.« less

Resource utilization model for the algorithm to architecture mapping model

NASA Technical Reports Server (NTRS)

Stoughton, John W.; Patel, Rakesh R.

1993-01-01

The analytical model for resource utilization and the variable node time and conditional node model for the enhanced ATAMM model for a real-time data flow architecture are presented in this research. The Algorithm To Architecture Mapping Model, ATAMM, is a Petri net based graph theoretic model developed at Old Dominion University, and is capable of modeling the execution of large-grained algorithms on a real-time data flow architecture. Using the resource utilization model, the resource envelope may be obtained directly from a given graph and, consequently, the maximum number of required resources may be evaluated. The node timing diagram for one iteration period may be obtained using the analytical resource envelope. The variable node time model, which describes the change in resource requirement for the execution of an algorithm under node time variation, is useful to expand the applicability of the ATAMM model to heterogeneous architectures. The model also describes a method of detecting the presence of resource limited mode and its subsequent prevention. Graphs with conditional nodes are shown to be reduced to equivalent graphs with time varying nodes and, subsequently, may be analyzed using the variable node time model to determine resource requirements. Case studies are performed on three graphs for the illustration of applicability of the analytical theories.

EdgeMaps: visualizing explicit and implicit relations

NASA Astrophysics Data System (ADS)

Dörk, Marian; Carpendale, Sheelagh; Williamson, Carey

2011-01-01

In this work, we introduce EdgeMaps as a new method for integrating the visualization of explicit and implicit data relations. Explicit relations are specific connections between entities already present in a given dataset, while implicit relations are derived from multidimensional data based on shared properties and similarity measures. Many datasets include both types of relations, which are often difficult to represent together in information visualizations. Node-link diagrams typically focus on explicit data connections, while not incorporating implicit similarities between entities. Multi-dimensional scaling considers similarities between items, however, explicit links between nodes are not displayed. In contrast, EdgeMaps visualize both implicit and explicit relations by combining and complementing spatialization and graph drawing techniques. As a case study for this approach we chose a dataset of philosophers, their interests, influences, and birthdates. By introducing the limitation of activating only one node at a time, interesting visual patterns emerge that resemble the aesthetics of fireworks and waves. We argue that the interactive exploration of these patterns may allow the viewer to grasp the structure of a graph better than complex node-link visualizations.

Risk of Subclinical Micrometastatic Disease in the Supraclavicular Nodal Bed According to the Anatomic Distribution in Patients With Advanced Breast Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reed, Valerie K.; Cavalcanti, Jose L.; Strom, Eric A.

Purpose: To determine the anatomic distribution of gross supraclavicular nodes within the supraclavicular fossa using 2-deoxy-2-[F-18] fluoro-d-glucose (FDG) positron emission tomography/computed tomography (PET/CT) scans, and to evaluate likely coverage of specific regions of the supraclavicular fossa using standard radiation fields. Methods and Materials: We identified 33 patients with advanced or metastatic breast cancer who had a PET/CT scan demonstrating hypermetabolic supraclavicular lymph nodes in 2005. The locations of the involved lymph nodes were mapped onto a single CT set of images of the supraclavicular fossa. These lymph nodes were also mapped onto the treatment-planning CT dataset of 4 patients treatedmore » in our institution (2 patients with biopsy-proven supraclavicular nodes and 2 patients with clinically negative supraclavicular nodes). Results: We were able to determine the distribution of 52 supraclavicular lymph nodes in 32 patients. Of 32 patients, 28 (87%) had a history of metastatic disease, and 2 patients had isolated nodal recurrences. Five patients had supraclavicular nodes posterior to the vertebral body transverse process, and several lymph nodes were in close proximity to the medial field border, raising the possibility of geographic miss in these areas. Conclusions: In patients with locally advanced disease, increased coverage of the supraclavicular fossa medially and posteriorly may be warranted.« less

Use of sentinel node mapping for cancer of the colon: 'to map or not to map".

PubMed

Thomas, Kristen A; Lechner, Jonathan; Shen, Perry; Waters, Gregory S; Geisinger, Kim R; Levine, Edward A

2006-07-01

Sentinel lymph node (SLN) mapping has become a cornerstone of oncologic surgery because it is a proven method for identifying nodal disease in melanoma and breast cancer. In addition, it can ameliorate the surgical morbidity secondary to lymphadenectomy. However, experience with SLN mapping for carcinoma of the colon and other visceral malignancies is limited. This study represents an update to our initial pilot experience with SLN mapping for carcinoma of the colon. Consenting patients over the age of 18 diagnosed with adenocarcinoma of the colon were included in this study. At the time of operation, 1 to 2 mL of isosulfan blue was injected with a 25-gauge needle into the subserosa at 4 sites around the edge of the palpable tumor. The SLN was identified visually and excised followed by a standard lymphadenectomy and surgical resection. SLNs were evaluated by standard hematoxylin and eosin (H&E) evaluation as well as immunohistochemical (IHC) techniques for carcinoembryonic antigen and cytokeratin if the H&E was negative. Sixty-nine patients underwent SLN mapping. A SLN was identified in 93 per cent (64 of 69) of patients. Nodal metastases were identified in 38 per cent (26 of 69) of patients overall. In 5 patients, the only positive node identified was the SLN, 2 of which were positive by IHC criteria alone. Therefore, 3 per cent (2 of 69) of patients were upstaged by SLN mapping. This technique was 100 per cent specific while being 46 per cent sensitive. Fourteen patients had false-negative SLNs. Metastasis to regional lymph nodes remains the key prognostic factor for colon cancer. SLN mapping is feasible for colon cancer and can identify a subset of patients who could benefit from adjuvant chemotherapy. Although SLN mapping did not alter the surgical management of colon cancer, it does make possible a more focused and cost-effective pathologic evaluation of nodal disease. We do not suggest routine utilization of SLN mapping for colon cancer, but we believe that the data supports proceeding with a national trial.

Studies on the biodistribution of dextrin nanoparticles

NASA Astrophysics Data System (ADS)

Gonçalves, C.; Ferreira, M. F. M.; Santos, A. C.; Prata, M. I. M.; Geraldes, C. F. G. C.; Martins, J. A.; Gama, F. M.

2010-07-01

The characterization of biodistribution is a central requirement in the development of biomedical applications based on the use of nanoparticles, in particular for controlled drug delivery. The blood circulation time, organ biodistribution and rate of excretion must be well characterized in the process of product development. In this work, the biodistribution of recently developed self-assembled dextrin nanoparticles is addressed. Functionalization of the dextrin nanoparticles with a DOTA-monoamide-type metal chelator, via click chemistry, is described. The metal chelator functionalized nanoparticles were labelled with a γ-emitting 153Sm3 + radioisotope and the blood clearance rate and organ biodistribution of the nanoparticles were obtained. The effect of PEG surface coating on the blood clearance rate and organ biodistribution of the nanoparticles was also studied.

A Specific Mapping Study Using Fluorescence Sentinel Lymph Node Detection in Patients with Intermediate- and High-risk Prostate Cancer Undergoing Extended Pelvic Lymph Node Dissection.

PubMed

Nguyen, Daniel P; Huber, Philipp M; Metzger, Tobias A; Genitsch, Vera; Schudel, Hans H; Thalmann, George N

2016-11-01

Sentinel lymph node (SLN) detection techniques have the potential to change the standard of surgical care for patients with prostate cancer. We performed a lymphatic mapping study and determined the value of fluorescence SLN detection with indocyanine green (ICG) for the detection of lymph node metastases in intermediate- and high-risk patients undergoing radical prostatectomy and extended pelvic lymph node dissection. A total of 42 patients received systematic or specific ICG injections into the prostate base, the midportion, the apex, the left lobe, or the right lobe. We found (1) that external and internal iliac regions encompass the majority of SLNs, (2) that common iliac regions contain up to 22% of all SLNs, (3) that a prostatic lobe can drain into the contralateral group of pelvic lymph nodes, and (4) that the fossa of Marcille also receives significant drainage. Among the 12 patients who received systematic ICG injections, 5 (42%) had a total of 29 lymph node metastases. Of these, 16 nodes were ICG positive, yielding 55% sensitivity. The complex drainage pattern of the prostate and the low sensitivity of ICG for the detection of lymph node metastases reported in our study highlight the difficulties related to the implementation of SNL techniques in prostate cancer. There is controversy about how extensive lymph node dissection (LND) should be during prostatectomy. We investigated the lymphatic drainage of the prostate and whether sentinel node fluorescence techniques would be useful to detect node metastases. We found that the drainage pattern is complex and that the sentinel node technique is not able to replace extended pelvic LND. Copyright © 2016. Published by Elsevier B.V.

Method of and apparatus for modeling interactions

DOEpatents

Budge, Kent G.

2004-01-13

A method and apparatus for modeling interactions can accurately model tribological and other properties and accommodate topological disruptions. Two portions of a problem space are represented, a first with a Lagrangian mesh and a second with an ALE mesh. The ALE and Lagrangian meshes are constructed so that each node on the surface of the Lagrangian mesh is in a known correspondence with adjacent nodes in the ALE mesh. The interaction can be predicted for a time interval. Material flow within the ALE mesh can accurately model complex interactions such as bifurcation. After prediction, nodes in the ALE mesh in correspondence with nodes on the surface of the Lagrangian mesh can be mapped so that they are once again adjacent to their corresponding Lagrangian mesh nodes. The ALE mesh can then be smoothed to reduce mesh distortion that might reduce the accuracy or efficiency of subsequent prediction steps. The process, from prediction through mapping and smoothing, can be repeated until a terminal condition is reached.

Sentinel lymph node mapping in gynecological oncology

PubMed Central

Du, Jiang; Li, Yaling; Wang, Qing; Batchu, Nasra; Zou, Junkai; Sun, Chao; Lv, Shulan; Song, Qing; Li, Qiling

2017-01-01

The intraoperative mapping of sentinel lymph nodes (SLNs) is part of the treatment strategy for a number of types of tumor. To retrospectively compare results from the mapping of pelvic SLNs for gynecological oncology, using distinct dyes, the present review was conducted to determine the clinical significance of SLN mapping for gynecological oncology. In addition, the present study aimed at identifying an improved choice for SLN mapping tracers in clinical application. Each dye exhibits demerits when applied in the clinical environment. The combination of radioisotopes and blue dyes was identified to exhibit the most accurate detection rate of SLN drainage of gynecological oncology. However, contrast agents were unable to identify whether a SLN is positive or negative for metastasis prior to pathologic examination; additional studies are required. PMID:29344213

MROrchestrator: A Fine-Grained Resource Orchestration Framework for MapReduce Clusters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, Bikash; Prabhakar, Ramya; Kandemir, Mahmut

2012-01-01

Efficient resource management in data centers and clouds running large distributed data processing frameworks like MapReduce is crucial for enhancing the performance of hosted applications and boosting resource utilization. However, existing resource scheduling schemes in Hadoop MapReduce allocate resources at the granularity of fixed-size, static portions of nodes, called slots. In this work, we show that MapReduce jobs have widely varying demands for multiple resources, making the static and fixed-size slot-level resource allocation a poor choice both from the performance and resource utilization standpoints. Furthermore, lack of co-ordination in the management of mul- tiple resources across nodes prevents dynamic slotmore » reconfigura- tion, and leads to resource contention. Motivated by this, we propose MROrchestrator, a MapReduce resource Orchestrator framework, which can dynamically identify resource bottlenecks, and resolve them through fine-grained, co-ordinated, and on- demand resource allocations. We have implemented MROrches- trator on two 24-node native and virtualized Hadoop clusters. Experimental results with a suite of representative MapReduce benchmarks demonstrate up to 38% reduction in job completion times, and up to 25% increase in resource utilization. We further show how popular resource managers like NGM and Mesos when augmented with MROrchestrator can hike up their performance.« less

Mapping of nodal disease in locally advanced prostate cancer: Rethinking the clinical target volume for pelvic nodal irradiation based on vascular rather than bony anatomy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shih, Helen A.; Harisinghani, Mukesh; Zietman, Anthony L.

2005-11-15

Purpose: Toxicity from pelvic irradiation could be reduced if fields were limited to likely areas of nodal involvement rather than using the standard 'four-field box.' We employed a novel magnetic resonance lymphangiographic technique to highlight the likely sites of occult nodal metastasis from prostate cancer. Methods and Materials: Eighteen prostate cancer patients with pathologically confirmed node-positive disease had a total of 69 pathologic nodes identifiable by lymphotropic nanoparticle-enhanced MRI and semiquantitative nodal analysis. Fourteen of these nodes were in the para-aortic region, and 55 were in the pelvis. The position of each of these malignant nodes was mapped to amore » common template based on its relation to skeletal or vascular anatomy. Results: Relative to skeletal anatomy, nodes covered a diffuse volume from the mid lumbar spine to the superior pubic ramus and along the sacrum and pelvic side walls. In contrast, the nodal metastases mapped much more tightly relative to the large pelvic vessels. A proposed pelvic clinical target volume to encompass the region at greatest risk of containing occult nodal metastases would include a 2.0-cm radial expansion volume around the distal common iliac and proximal external and internal iliac vessels that would encompass 94.5% of the pelvic nodes at risk as defined by our node-positive prostate cancer patient cohort. Conclusions: Nodal metastases from prostate cancer are largely localized along the major pelvic vasculature. Defining nodal radiation treatment portals based on vascular rather than bony anatomy may allow for a significant decrease in normal pelvic tissue irradiation and its associated toxicities.« less

Biodistribution detection of Photofrin porfimer sodium and benzoporphyrin derivative using a fiber optic sensor and ratio fluorometry

NASA Astrophysics Data System (ADS)

Vari, Sandor G.; Papazoglou, Theodore G.; Papaioannou, Thanassis; Stavridi, Marigo; Pergadia, Vani R.; Fishbein, Michael C.; van der Veen, Maurits J.; Thomas, Reem; Grundfest, Warren S.

1994-03-01

Laser induced fluorescence spectroscopy (LIFS) was used to detect the presence of PHOTOFRINR porfimer sodium and Benzoporphyrin derivative-monoacid, ring A (BPD-MA) in various tissues. Lobund Wistar rats (n equals 49) inoculated with rat prostatic adenocarcinoma (PA-III) were injected with PHOTOFRINR porfimer sodium (7.5 - 0.25 mg/kg) and BPD (0.50 - 25 mg/kg) intravenously. A Helium-Cadmium laser (442 nm) was used as an excitation source. Our study showed that the amount of PHOTOFRINR porfimer sodium and BPD-MA which localizes in the metastatic lymph nodes is higher than in tumor and all other healthy tissues. Laser induced fluorescence spectroscopy may be a feasible method to detect the distribution of photosensitizers or other fluorescent compounds in vivo.

Designing liposomal adjuvants for the next generation of vaccines.

PubMed

Perrie, Yvonne; Crofts, Fraser; Devitt, Andrew; Griffiths, Helen R; Kastner, Elisabeth; Nadella, Vinod

2016-04-01

Liposomes not only offer the ability to enhance drug delivery, but can effectively act as vaccine delivery systems and adjuvants. Their flexibility in size, charge, bilayer rigidity and composition allow for targeted antigen delivery via a range of administration routes. In the development of liposomal adjuvants, the type of immune response promoted has been linked to their physico-chemical characteristics, with the size and charge of the liposomal particles impacting on liposome biodistribution, exposure in the lymph nodes and recruitment of the innate immune system. The addition of immunostimulatory agents can further potentiate their immunogenic properties. Here, we outline the attributes that should be considered in the design and manufacture of liposomal adjuvants for the delivery of sub-unit and nucleic acid based vaccines. Copyright © 2015 Elsevier B.V. All rights reserved.

Virtual optical network mapping and core allocation in elastic optical networks using multi-core fibers

NASA Astrophysics Data System (ADS)

Xuan, Hejun; Wang, Yuping; Xu, Zhanqi; Hao, Shanshan; Wang, Xiaoli

2017-11-01

Virtualization technology can greatly improve the efficiency of the networks by allowing the virtual optical networks to share the resources of the physical networks. However, it will face some challenges, such as finding the efficient strategies for virtual nodes mapping, virtual links mapping and spectrum assignment. It is even more complex and challenging when the physical elastic optical networks using multi-core fibers. To tackle these challenges, we establish a constrained optimization model to determine the optimal schemes of optical network mapping, core allocation and spectrum assignment. To solve the model efficiently, tailor-made encoding scheme, crossover and mutation operators are designed. Based on these, an efficient genetic algorithm is proposed to obtain the optimal schemes of the virtual nodes mapping, virtual links mapping, core allocation. The simulation experiments are conducted on three widely used networks, and the experimental results show the effectiveness of the proposed model and algorithm.

Large-scale seismic waveform quality metric calculation using Hadoop

NASA Astrophysics Data System (ADS)

Magana-Zook, S.; Gaylord, J. M.; Knapp, D. R.; Dodge, D. A.; Ruppert, S. D.

2016-09-01

In this work we investigated the suitability of Hadoop MapReduce and Apache Spark for large-scale computation of seismic waveform quality metrics by comparing their performance with that of a traditional distributed implementation. The Incorporated Research Institutions for Seismology (IRIS) Data Management Center (DMC) provided 43 terabytes of broadband waveform data of which 5.1 TB of data were processed with the traditional architecture, and the full 43 TB were processed using MapReduce and Spark. Maximum performance of 0.56 terabytes per hour was achieved using all 5 nodes of the traditional implementation. We noted that I/O dominated processing, and that I/O performance was deteriorating with the addition of the 5th node. Data collected from this experiment provided the baseline against which the Hadoop results were compared. Next, we processed the full 43 TB dataset using both MapReduce and Apache Spark on our 18-node Hadoop cluster. These experiments were conducted multiple times with various subsets of the data so that we could build models to predict performance as a function of dataset size. We found that both MapReduce and Spark significantly outperformed the traditional reference implementation. At a dataset size of 5.1 terabytes, both Spark and MapReduce were about 15 times faster than the reference implementation. Furthermore, our performance models predict that for a dataset of 350 terabytes, Spark running on a 100-node cluster would be about 265 times faster than the reference implementation. We do not expect that the reference implementation deployed on a 100-node cluster would perform significantly better than on the 5-node cluster because the I/O performance cannot be made to scale. Finally, we note that although Big Data technologies clearly provide a way to process seismic waveform datasets in a high-performance and scalable manner, the technology is still rapidly changing, requires a high degree of investment in personnel, and will likely require significant changes in other parts of our infrastructure. Nevertheless, we anticipate that as the technology matures and third-party tool vendors make it easier to manage and operate clusters, Hadoop (or a successor) will play a large role in our seismic data processing.

Pervasive Radio Mapping of Industrial Environments Using a Virtual Reality Approach

PubMed Central

Nedelcu, Adrian-Valentin; Machedon-Pisu, Mihai; Talaba, Doru

2015-01-01

Wireless communications in industrial environments are seriously affected by reliability and performance issues, due to the multipath nature of obstacles within such environments. Special attention needs to be given to planning a wireless industrial network, so as to find the optimum spatial position for each of the nodes within the network, and especially for key nodes such as gateways or cluster heads. The aim of this paper is to present a pervasive radio mapping system which captures (senses) data regarding the radio spectrum, using low-cost wireless sensor nodes. This data is the input of radio mapping algorithms that generate electromagnetic propagation profiles. Such profiles are used for identifying obstacles within the environment and optimum propagation pathways. With the purpose of further optimizing the radio planning process, the authors propose a novel human-network interaction (HNI) paradigm that uses 3D virtual environments in order to display the radio maps in a natural, easy-to-perceive manner. The results of this approach illustrate its added value to the field of radio resource planning of industrial communication systems. PMID:26167533

Pervasive Radio Mapping of Industrial Environments Using a Virtual Reality Approach.

PubMed

Nedelcu, Adrian-Valentin; Machedon-Pisu, Mihai; Duguleana, Mihai; Talaba, Doru

2015-01-01

Wireless communications in industrial environments are seriously affected by reliability and performance issues, due to the multipath nature of obstacles within such environments. Special attention needs to be given to planning a wireless industrial network, so as to find the optimum spatial position for each of the nodes within the network, and especially for key nodes such as gateways or cluster heads. The aim of this paper is to present a pervasive radio mapping system which captures (senses) data regarding the radio spectrum, using low-cost wireless sensor nodes. This data is the input of radio mapping algorithms that generate electromagnetic propagation profiles. Such profiles are used for identifying obstacles within the environment and optimum propagation pathways. With the purpose of further optimizing the radio planning process, the authors propose a novel human-network interaction (HNI) paradigm that uses 3D virtual environments in order to display the radio maps in a natural, easy-to-perceive manner. The results of this approach illustrate its added value to the field of radio resource planning of industrial communication systems.

Sentinel lymph node biopsy from the vantage point of an oncologic surgeon.

PubMed

Wilson, Lori L

2009-01-01

Sentinel lymph node biopsy has greatly influenced the surgical management of clinically localized primary melanoma. Lymphatic mapping and sentinel lymph node biopsy have been used for the selective management of the draining regional lymph node basin of primary cutaneous melanoma. Oncologic surgeons have adopted this procedure to selectively identify occult nodal status in melanoma patients who are at a higher risk of regional metastasis. The current standard of treatment of tumor-positive sentinel lymph node metastasis is immediate completion lymphadenectomy, but considerable debate surrounds the utility of this procedure. This contribution reviews development, technical aspects, selective management of the lymph node basin, and sentinel lymph node biopsy techniques.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karakaya, Mahmut; Qi, Hairong

This paper addresses the communication and energy efficiency in collaborative visual sensor networks (VSNs) for people localization, a challenging computer vision problem of its own. We focus on the design of a light-weight and energy efficient solution where people are localized based on distributed camera nodes integrating the so-called certainty map generated at each node, that records the target non-existence information within the camera s field of view. We first present a dynamic itinerary for certainty map integration where not only each sensor node transmits a very limited amount of data but that a limited number of camera nodes ismore » involved. Then, we perform a comprehensive analytical study to evaluate communication and energy efficiency between different integration schemes, i.e., centralized and distributed integration. Based on results obtained from analytical study and real experiments, the distributed method shows effectiveness in detection accuracy as well as energy and bandwidth efficiency.« less

A grid matrix-based Raman spectroscopic method to characterize different cell milieu in biopsied axillary sentinel lymph nodes of breast cancer patients.

PubMed

Som, Dipasree; Tak, Megha; Setia, Mohit; Patil, Asawari; Sengupta, Amit; Chilakapati, C Murali Krishna; Srivastava, Anurag; Parmar, Vani; Nair, Nita; Sarin, Rajiv; Badwe, R

2016-01-01

Raman spectroscopy which is based upon inelastic scattering of photons has a potential to emerge as a noninvasive bedside in vivo or ex vivo molecular diagnostic tool. There is a need to improve the sensitivity and predictability of Raman spectroscopy. We developed a grid matrix-based tissue mapping protocol to acquire cellular-specific spectra that also involved digital microscopy for localizing malignant and lymphocytic cells in sentinel lymph node biopsy sample. Biosignals acquired from specific cellular milieu were subjected to an advanced supervised analytical method, i.e., cross-correlation and peak-to-peak ratio in addition to PCA and PC-LDA. We observed decreased spectral intensity as well as shift in the spectral peaks of amides and lipid bands in the completely metastatic (cancer cells) lymph nodes with high cellular density. Spectral library of normal lymphocytes and metastatic cancer cells created using the cellular specific mapping technique can be utilized to create an automated smart diagnostic tool for bench side screening of sampled lymph nodes. Spectral library of normal lymphocytes and metastatic cancer cells created using the cellular specific mapping technique can be utilized to develop an automated smart diagnostic tool for bench side screening of sampled lymph nodes supported by ongoing global research in developing better technology and signal and big data processing algorithms.

Biomechanics Simulations Using Cubic Hermite Meshes with Extraordinary Nodes for Isogeometric Cardiac Modeling

PubMed Central

Gonzales, Matthew J.; Sturgeon, Gregory; Segars, W. Paul; McCulloch, Andrew D.

2016-01-01

Cubic Hermite hexahedral finite element meshes have some well-known advantages over linear tetrahedral finite element meshes in biomechanical and anatomic modeling using isogeometric analysis. These include faster convergence rates as well as the ability to easily model rule-based anatomic features such as cardiac fiber directions. However, it is not possible to create closed complex objects with only regular nodes; these objects require the presence of extraordinary nodes (nodes with 3 or >= 5 adjacent elements in 2D) in the mesh. The presence of extraordinary nodes requires new constraints on the derivatives of adjacent elements to maintain continuity. We have developed a new method that uses an ensemble coordinate frame at the nodes and a local-to-global mapping to maintain continuity. In this paper, we make use of this mapping to create cubic Hermite models of the human ventricles and a four-chamber heart. We also extend the methods to the finite element equations to perform biomechanics simulations using these meshes. The new methods are validated using simple test models and applied to anatomically accurate ventricular meshes with valve annuli to simulate complete cardiac cycle simulations. PMID:27182096

Distributed Sensor Fusion for Scalar Field Mapping Using Mobile Sensor Networks.

PubMed

La, Hung Manh; Sheng, Weihua

2013-04-01

In this paper, autonomous mobile sensor networks are deployed to measure a scalar field and build its map. We develop a novel method for multiple mobile sensor nodes to build this map using noisy sensor measurements. Our method consists of two parts. First, we develop a distributed sensor fusion algorithm by integrating two different distributed consensus filters to achieve cooperative sensing among sensor nodes. This fusion algorithm has two phases. In the first phase, the weighted average consensus filter is developed, which allows each sensor node to find an estimate of the value of the scalar field at each time step. In the second phase, the average consensus filter is used to allow each sensor node to find a confidence of the estimate at each time step. The final estimate of the value of the scalar field is iteratively updated during the movement of the mobile sensors via weighted average. Second, we develop the distributed flocking-control algorithm to drive the mobile sensors to form a network and track the virtual leader moving along the field when only a small subset of the mobile sensors know the information of the leader. Experimental results are provided to demonstrate our proposed algorithms.

Motion planning with complete knowledge using a colored SOM.

PubMed

Vleugels, J; Kok, J N; Overmars, M

1997-01-01

The motion planning problem requires that a collision-free path be determined for a robot moving amidst a fixed set of obstacles. Most neural network approaches to this problem are for the situation in which only local knowledge about the configuration space is available. The main goal of the paper is to show that neural networks are also suitable tools in situations with complete knowledge of the configuration space. In this paper we present an approach that combines a neural network and deterministic techniques. We define a colored version of Kohonen's self-organizing map that consists of two different classes of nodes. The network is presented with random configurations of the robot and, from this information, it constructs a road map of possible motions in the work space. The map is a growing network, and different nodes are used to approximate boundaries of obstacles and the Voronoi diagram of the obstacles, respectively. In a second phase, the positions of the two kinds of nodes are combined to obtain the road map. In this way a number of typical problems with small obstacles and passages are avoided, and the required number of nodes for a given accuracy is within reasonable limits. This road map is searched to find a motion connecting the given source and goal configurations of the robot. The algorithm is simple and general; the only specific computation that is required is a check for intersection of two polygons. We implemented the algorithm for planar robots allowing both translation and rotation and experiments show that compared to conventional techniques it performs well, even for difficult motion planning scenes.

Predictive model of outcome of targeted nodal assessment in colorectal cancer.

PubMed

Nissan, Aviram; Protic, Mladjan; Bilchik, Anton; Eberhardt, John; Peoples, George E; Stojadinovic, Alexander

2010-02-01

Improvement in staging accuracy is the principal aim of targeted nodal assessment in colorectal carcinoma. Technical factors independently predictive of false negative (FN) sentinel lymph node (SLN) mapping should be identified to facilitate operative decision making. To define independent predictors of FN SLN mapping and to develop a predictive model that could support surgical decisions. Data was analyzed from 2 completed prospective clinical trials involving 278 patients with colorectal carcinoma undergoing SLN mapping. Clinical outcome of interest was FN SLN(s), defined as one(s) with no apparent tumor cells in the presence of non-SLN metastases. To assess the independent predictive effect of a covariate for a nominal response (FN SLN), a logistic regression model was constructed and parameters estimated using maximum likelihood. A probabilistic Bayesian model was also trained and cross validated using 10-fold train-and-test sets to predict FN SLN mapping. Area under the curve (AUC) from receiver operating characteristics curves of these predictions was calculated to determine the predictive value of the model. Number of SLNs (<3; P = 0.03) and tumor-replaced nodes (P < 0.01) independently predicted FN SLN. Cross validation of the model created with Bayesian Network Analysis effectively predicted FN SLN (area under the curve = 0.84-0.86). The positive and negative predictive values of the model are 83% and 97%, respectively. This study supports a minimum threshold of 3 nodes for targeted nodal assessment in colorectal cancer, and establishes sufficient basis to conclude that SLN mapping and biopsy cannot be justified in the presence of clinically apparent tumor-replaced nodes.

Mapping Patterns of Ipsilateral Supraclavicular Nodal Metastases in Breast Cancer: Rethinking the Clinical Target Volume for High-risk Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jing, Hao; Wang, Shu-Lian, E-mail: wsl20040118@yahoo.com; Li, Jing

2015-10-01

Purpose: To map the location of metastatic supraclavicular (SCV) lymph nodes (LNMs) in breast cancer patients with SCV node involvement and determine whether and where the radiation therapy clinical target volume (CTV) of this region could be modified in high-risk subsets. Methods and Materials: Fifty-five patients with metastatic SCV LNMs were eligible for geographic mapping and atlas coverage analysis. All LNMs and their epicenters were registered proportionally by referencing the surrounding landmarks onto simulation computed tomography images of a standard patient. CTVs based on selected SCV atlases, including the one by the Radiation Therapy Oncology Group (RTOG) were contoured. Amore » modified SCV CTV was tried and shown to have better involved-node coverage and thus theoretically improved prophylaxis in this setting. Results: A total of 50 (91%) and 45 (81.8%) patients had LNMs in the medial and lateral SCV subregions, respectively. Also, 36 patients (65.5%) had LNMs located at the junction of the jugular-subclavian veins. All nodes were covered in only 25.5% to 41.8% of patients by different atlases. The RTOG atlas covered all nodes in 25.5% of patients. Stratified by the nodes in all the patients as a whole, 49.2% to 81.3% were covered, and the RTOG atlas covered 62.6%. The lateral and posterior borders were the most overlooked locations. Modification by extending the borders to natural anatomic barriers allowed the new CTV to cover all the nodes in 81.8% of patients and encompass 96.1% of all the nodes. Conclusions: According to the distribution of SCV LNMs, the extent of existing atlases might not be adequate for potential metastatic sites in certain groups of patients. The extension of the lateral and posterior CTV borders in high-risk or recurrent patients might be a reasonable approach for increasing coverage. However, additional data in more homogeneous populations with localized disease are needed before routine application.« less

Sulfonation of Tyrosine as a Method To Improve Biodistribution of Peptide-Based Radiotracers: Novel 18F-Labeled Cyclic RGD Analogues.

PubMed

Haskali, Mohammad B; Denoyer, Delphine; Noonan, Wayne; Culinane, Carleen; Rangger, Christine; Pouliot, Normand; Haubner, Roland; Roselt, Peter D; Hicks, Rodney J; Hutton, Craig A

2017-04-03

Control of the biodistribution of radiolabeled peptides has proven to be a major challenge in their application as imaging agents for positron emission tomography (PET). Modification of peptide hydrophilicity in order to increase renal clearance has been a common endeavor to improve overall biodistribution. Herein, we examine the effect of site-specific sulfonation of tyrosine moieties in cyclic(RGDyK) peptides as a means to enhance their hydrophilicity and improve their biodistribution. The novel sulfonated cyclic(RGDyK) peptides were conjugated directly to 4-nitrophenyl 2-[ 18 F]fluoropropionate, and the biodistribution of the radiolabeled peptides was compared with that of their nonsulfonated, clinically relevant counterparts, [ 18 F]GalactoRGD and [ 18 F]FPPRGD2. Site-specific sulfonation of the tyrosine residues was shown to increase hydrophilicity and improve biodistribution of the RGD peptides, despite contributing just 79 Da toward the MW, compared with 189 Da for both the "Galacto" and mini-PEG moieties, suggesting this may be a broadly applicable approach to enhancing biodistribution of radiolabeled peptides.

Comparison of prevalence estimation of Mycobacterium avium subsp. paratuberculosis infection by sampling slaughtered cattle with macroscopic lesions vs. systematic sampling.

PubMed

Elze, J; Liebler-Tenorio, E; Ziller, M; Köhler, H

2013-07-01

The objective of this study was to identify the most reliable approach for prevalence estimation of Mycobacterium avium ssp. paratuberculosis (MAP) infection in clinically healthy slaughtered cattle. Sampling of macroscopically suspect tissue was compared to systematic sampling. Specimens of ileum, jejunum, mesenteric and caecal lymph nodes were examined for MAP infection using bacterial microscopy, culture, histopathology and immunohistochemistry. MAP was found most frequently in caecal lymph nodes, but sampling more tissues optimized the detection rate. Examination by culture was most efficient while combination with histopathology increased the detection rate slightly. MAP was detected in 49/50 animals with macroscopic lesions representing 1.35% of the slaughtered cattle examined. Of 150 systematically sampled macroscopically non-suspect cows, 28.7% were infected with MAP. This indicates that the majority of MAP-positive cattle are slaughtered without evidence of macroscopic lesions and before clinical signs occur. For reliable prevalence estimation of MAP infection in slaughtered cattle, systematic random sampling is essential.

Map of physics

NASA Astrophysics Data System (ADS)

2008-10-01

Based on bibliometric data from information-services provider Thomson Reuters, this map reveals "core areas" of physics, shown as coloured circular nodes, and the relationship between these subdisciplines, shown as lines.

Functional, Anatomical, and Molecular Investigation of the Cardiac Conduction System and Arrhythmogenic Atrioventricular Ring Tissue in the Rat Heart

PubMed Central

Atkinson, Andrew J.; Logantha, Sunil Jit R. J.; Hao, Guoliang; Yanni, Joseph; Fedorenko, Olga; Sinha, Aditi; Gilbert, Stephen H.; Benson, Alan P.; Buckley, David L.; Anderson, Robert H.; Boyett, Mark R.; Dobrzynski, Halina

2013-01-01

Background The cardiac conduction system consists of the sinus node, nodal extensions, atrioventricular (AV) node, penetrating bundle, bundle branches, and Purkinje fibers. Node‐like AV ring tissue also exists at the AV junctions, and the right and left rings unite at the retroaortic node. The study aims were to (1) construct a 3‐dimensional anatomical model of the AV rings and retroaortic node, (2) map electrical activation in the right ring and study its action potential characteristics, and (3) examine gene expression in the right ring and retroaortic node. Methods and Results Three‐dimensional reconstruction (based on magnetic resonance imaging, histology, and immunohistochemistry) showed the extent and organization of the specialized tissues (eg, how the AV rings form the right and left nodal extensions into the AV node). Multiextracellular electrode array and microelectrode mapping of isolated right ring preparations revealed robust spontaneous activity with characteristic diastolic depolarization. Using laser microdissection gene expression measured at the mRNA level (using quantitative PCR) and protein level (using immunohistochemistry and Western blotting) showed that the right ring and retroaortic node, like the sinus node and AV node but, unlike ventricular muscle, had statistically significant higher expression of key transcription factors (including Tbx3, Msx2, and Id2) and ion channels (including HCN4, Cav3.1, Cav3.2, Kv1.5, SK1, Kir3.1, and Kir3.4) and lower expression of other key ion channels (Nav1.5 and Kir2.1). Conclusions The AV rings and retroaortic node possess gene expression profiles similar to that of the AV node. Ion channel expression and electrophysiological recordings show the AV rings could act as ectopic pacemakers and a source of atrial tachycardia. PMID:24356527

The Feasibility and Oncological Safety of Axillary Reverse Mapping in Patients with Breast Cancer: A Systematic Review and Meta-Analysis of Prospective Studies

PubMed Central

Han, Chao; Yang, Ben; Zuo, Wen-Shu; Zheng, Gang; Yang, Li; Zheng, Mei-Zhu

2016-01-01

Objective The axillary reverse mapping (ARM) technique has recently been developed to prevent lymphedema by preserving the arm lymphatic drainage during sentinel lymph node biopsy (SLNB) or axillary lymph node dissection (ALND) procedures. The objective of this systematic review and meta-analysis was to evaluate the feasibility and oncological safety of ARM. Methods We searched Medline, Embase, Web of science, Scopus, and the Cochrane Library for relevant prospective studies. The identification rate of ARM nodes, the crossover rate of SLN-ARM nodes, the proportion of metastatic ARM nodes, and the incidence of complications were pooled into meta-analyses by the random-effects model. Results A total of 24 prospective studies were included into meta-analyses, of which 11 studies reported ARM during SLNB, and 18 studies reported ARM during SLNB. The overall identification rate of ARM nodes was 38.2% (95% CI 32.9%-43.8%) during SLNB and 82.8% (78.0%-86.6%) during ALND, respectively. The crossover rate of SLN-ARM nodes was 19.6% (95% CI 14.4%-26.1%). The metastatic rate of ARM nodes was 16.9% (95% CI 14.2%-20.1%). The pooled incidence of lymphedema was 4.1% (95% CI 2.9–5.9%) for patients undergoing ARM procedure. Conclusions The ARM procedure was feasible during ALND. Nevertheless, it was restricted by low identification rate of ARM nodes during SLNB. ARM was beneficial for preventing lymphedema. However, this technique should be performed with caution given the possibility of crossover SLN-ARM nodes and metastatic ARM nodes. ARM appeared to be unsuitable for patients with clinically positive breast cancer due to oncological safety concern. PMID:26919589

The Effectiveness of an Online Knowledge Map Instructional Presentation

ERIC Educational Resources Information Center

Foor, Jamie L.

2011-01-01

In this study, I investigated the effectiveness of the knowledge map (k-map) instructional strategy compared to a text-based presentation in an online environment. K-maps consist of node-link representations of concepts that together form the content of a topic or domain. The benefits of using k-maps are that concepts and ideas are represented as…

Sentinel Node Detection in Head and Neck Malignancies: Innovations in Radioguided Surgery

PubMed Central

Vermeeren, L.; Klop, W. M. C.; van den Brekel, M. W. M.; Balm, A. J. M.; Nieweg, O. E.; Valdés Olmos, R. A.

2009-01-01

Sentinel node mapping is becoming a routine procedure for staging of various malignancies, because it can determine lymph node status more precisely. Due to anatomical problems, localizing sentinel nodes in the head and neck region on the basis of conventional images can be difficult. New diagnostic tools can provide better visualization of sentinel nodes. In an attempt to keep up with possible scientific progress, this article reviews new and innovative tools for sentinel node localization in this specific area. The overview comprises a short introduction of the sentinel node procedure as well as indications in the head and neck region. Then the results of SPECT/CT for sentinel node detection are described. Finally, a portable gamma camera to enable intraoperative real-time imaging with improved sentinel node detection is described. PMID:20016804

Sentinel Lymph Node Evaluation in Women with Cervical Cancer

PubMed Central

Holman, Laura L.; Levenback, Charles F.; Frumovitz, Michael

2014-01-01

Lymph node status is the most important prognosticator of survival among women with early stage cervical cancer. This means that many cervical cancer patients will undergo pelvic lymphadenectomy as part of their treatment. Unfortunately, this procedure is associated with significant morbidity. Utilizing the sentinel lymph node technique for women with cervical cancer has the potential to decrease this morbidity. Multiple studies have suggested that sentinel lymph node mapping in these patients is feasible with excellent detection rates and sensitivity. This review examines the current body of literature regarding sentinel lymph node biopsy among women with cervical cancer. PMID:24407177

Centrally managed unified shared virtual address space

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilkes, John

Systems, apparatuses, and methods for managing a unified shared virtual address space. A host may execute system software and manage a plurality of nodes coupled to the host. The host may send work tasks to the nodes, and for each node, the host may externally manage the node's view of the system's virtual address space. Each node may have a central processing unit (CPU) style memory management unit (MMU) with an internal translation lookaside buffer (TLB). In one embodiment, the host may be coupled to a given node via an input/output memory management unit (IOMMU) interface, where the IOMMU frontendmore » interface shares the TLB with the given node's MMU. In another embodiment, the host may control the given node's view of virtual address space via memory-mapped control registers.« less

Physiologically based pharmacokinetic modeling of PLGA nanoparticles with varied mPEG content

PubMed Central

Li, Mingguang; Panagi, Zoi; Avgoustakis, Konstantinos; Reineke, Joshua

2012-01-01

Biodistribution of nanoparticles is dependent on their physicochemical properties (such as size, surface charge, and surface hydrophilicity). Clear and systematic understanding of nanoparticle properties’ effects on their in vivo performance is of fundamental significance in nanoparticle design, development and optimization for medical applications, and toxicity evaluation. In the present study, a physiologically based pharmacokinetic model was utilized to interpret the effects of nanoparticle properties on previously published biodistribution data. Biodistribution data for five poly(lactic-co-glycolic) acid (PLGA) nanoparticle formulations prepared with varied content of monomethoxypoly (ethyleneglycol) (mPEG) (PLGA, PLGA-mPEG256, PLGA-mPEG153, PLGA-mPEG51, PLGA-mPEG34) were collected in mice after intravenous injection. A physiologically based pharmacokinetic model was developed and evaluated to simulate the mass-time profiles of nanoparticle distribution in tissues. In anticipation that the biodistribution of new nanoparticle formulations could be predicted from the physiologically based pharmacokinetic model, multivariate regression analysis was performed to build the relationship between nanoparticle properties (size, zeta potential, and number of PEG molecules per unit surface area) and biodistribution parameters. Based on these relationships, characterized physicochemical properties of PLGA-mPEG495 nanoparticles (a sixth formulation) were used to calculate (predict) biodistribution profiles. For all five initial formulations, the developed model adequately simulates the experimental data indicating that the model is suitable for description of PLGA-mPEG nanoparticle biodistribution. Further, the predicted biodistribution profiles of PLGA-mPEG495 were close to experimental data, reflecting properly developed property–biodistribution relationships. PMID:22419876

Mapping edge-based traffic measurements onto the internal links in MPLS network

NASA Astrophysics Data System (ADS)

Zhao, Guofeng; Tang, Hong; Zhang, Yi

2004-09-01

Applying multi-protocol label switching techniques to IP-based backbone for traffic engineering goals has shown advantageous. Obtaining a volume of load on each internal link of the network is crucial for traffic engineering applying. Though collecting can be available for each link, such as applying traditional SNMP scheme, the approach may cause heavy processing load and sharply degrade the throughput of the core routers. Then monitoring merely at the edge of the network and mapping the measurements onto the core provides a good alternative way. In this paper, we explore a scheme for traffic mapping with edge-based measurements in MPLS network. It is supposed that the volume of traffic on each internal link over the domain would be mapped onto by measurements available only at ingress nodes. We apply path-based measurements at ingress nodes without enabling measurements in the core of the network. We propose a method that can infer a path from the ingress to the egress node using label distribution protocol without collecting routing data from core routers. Based on flow theory and queuing theory, we prove that our approach is effective and present the algorithm for traffic mapping. We also show performance simulation results that indicate potential of our approach.

The vascularized groin lymph node flap (VGLN): Anatomical study and flap planning using multi-detector CT scanner. The golden triangle for flap harvesting.

PubMed

Zeltzer, Assaf A; Anzarut, Alexander; Braeckmans, Delphine; Seidenstuecker, Katrin; Hendrickx, Benoit; Van Hedent, Eddy; Hamdi, Moustapha

2017-09-01

A growing number of surgeons perform lymph node transfers for the treatment of lymphedema. When harvesting a vascularized lymph node groin flap (VGLNF) one of the major concerns is the potential risk of iatrogenic lymphedema of the donor-site. This article helps understanding of the lymph node distribution of the groin in order to minimize this risk. Fifty consecutive patients undergoing abdominal mapping by multi-detector CT scanner were included and 100 groins analyzed. The groin was divided in three zones (of which zone II is the safe zone) and lymph nodes were counted and mapped with their distances to anatomic landmarks. Further node units were plotted and counted. The average age was 48 years. A mean number of nodes of 6.5/groin was found. In zone II, which is our zone of interest a mean of 3.1 nodes were counted with a mean size of 7.8 mm. In three patients no nodes were found in zone II. In five patients nodes were seen in zone II but were not sufficient in size or number to be considered a lymph node unit. On average the lymph node unit in zone II was found to be 48.3 mm from the pubic tubercle when projected on a line from the pubic tubercle to the anterior superior iliac spine, 16.0 mm caudal to this line, and 20.4 mm above the groin crease. On average the lymph node unit was a mean of 41.7 mm lateral to the SCIV-SIEV confluence. This study provides increased understanding of the lymphatic anatomy in zone II of the groin flap and suggests a refined technique for designing the VGLNF. As with any flap there is a degree of individual patient variability. However, having information on the most common anatomy and flap design is of great value. © 2017 Wiley Periodicals, Inc.

The Japan Lung Cancer Society–Japanese Society for Radiation Oncology consensus-based computed tomographic atlas for defining regional lymph node stations in radiotherapy for lung cancer

PubMed Central

Itazawa, Tomoko; Tamaki, Yukihisa; Komiyama, Takafumi; Nishimura, Yasumasa; Nakayama, Yuko; Ito, Hiroyuki; Ohde, Yasuhisa; Kusumoto, Masahiko; Sakai, Shuji; Suzuki, Kenji; Watanabe, Hirokazu; Asamura, Hisao

2017-01-01

The purpose of this study was to develop a consensus-based computed tomographic (CT) atlas that defines lymph node stations in radiotherapy for lung cancer based on the lymph node map of the International Association for the Study of Lung Cancer (IASLC). A project group in the Japanese Radiation Oncology Study Group (JROSG) initially prepared a draft of the atlas in which lymph node Stations 1–11 were illustrated on axial CT images. Subsequently, a joint committee of the Japan Lung Cancer Society (JLCS) and the Japanese Society for Radiation Oncology (JASTRO) was formulated to revise this draft. The committee consisted of four radiation oncologists, four thoracic surgeons and three thoracic radiologists. The draft prepared by the JROSG project group was intensively reviewed and discussed at four meetings of the committee over several months. Finally, we proposed definitions for the regional lymph node stations and the consensus-based CT atlas. This atlas was approved by the Board of Directors of JLCS and JASTRO. This resulted in the first official CT atlas for defining regional lymph node stations in radiotherapy for lung cancer authorized by the JLCS and JASTRO. In conclusion, the JLCS–JASTRO consensus-based CT atlas, which conforms to the IASLC lymph node map, was established. PMID:27609192

The evaluation of multi-structure, multi-atlas pelvic anatomy features in a prostate MR lymphography CAD system

NASA Astrophysics Data System (ADS)

Meijs, M.; Debats, O.; Huisman, H.

2015-03-01

In prostate cancer, the detection of metastatic lymph nodes indicates progression from localized disease to metastasized cancer. The detection of positive lymph nodes is, however, a complex and time consuming task for experienced radiologists. Assistance of a two-stage Computer-Aided Detection (CAD) system in MR Lymphography (MRL) is not yet feasible due to the large number of false positives in the first stage of the system. By introducing a multi-structure, multi-atlas segmentation, using an affine transformation followed by a B-spline transformation for registration, the organ location is given by a mean density probability map. The atlas segmentation is semi-automatically drawn with ITK-SNAP, using Active Contour Segmentation. Each anatomic structure is identified by a label number. Registration is performed using Elastix, using Mutual Information and an Adaptive Stochastic Gradient optimization. The dataset consists of the MRL scans of ten patients, with lymph nodes manually annotated in consensus by two expert readers. The feature map of the CAD system consists of the Multi-Atlas and various other features (e.g. Normalized Intensity and multi-scale Blobness). The voxel-based Gentleboost classifier is evaluated using ROC analysis with cross validation. We show in a set of 10 studies that adding multi-structure, multi-atlas anatomical structure likelihood features improves the quality of the lymph node voxel likelihood map. Multiple structure anatomy maps may thus make MRL CAD more feasible.

The Added Value of a Single-photon Emission Computed Tomography-Computed Tomography in Sentinel Lymph Node Mapping in Patients with Breast Cancer and Malignant Melanoma.

PubMed

Bennie, George; Vorster, Mariza; Buscombe, John; Sathekge, Mike

2015-01-01

Single-photon emission computed tomography-computed tomography (SPECT-CT) allows for physiological and anatomical co-registration in sentinel lymph node (SLN) mapping and offers additional benefits over conventional planar imaging. However, the clinical relevance when considering added costs and radiation burden of these reported benefits remains somewhat uncertain. This study aimed to evaluate the possible added value of SPECT-CT and intra-operative gamma-probe use over planar imaging alone in the South African setting. 80 patients with breast cancer or malignant melanoma underwent both planar and SPECT-CT imaging for SLN mapping. We assessed and compared the number of nodes detected on each study, false positive and negative findings, changes in surgical approach and or patient management. In all cases where a sentinel node was identified, SPECT-CT was more accurate anatomically. There was a significant change in surgical approach in 30 cases - breast cancer (n = 13; P 0.001) and malignant melanoma (n = 17; P 0.0002). In 4 cases a node not identified on planar imaging was seen on SPECT-CT. In 16 cases additional echelon nodes were identified. False positives were excluded by SPECT-CT in 12 cases. The addition of SPECT-CT and use of intra-operative gamma-probe to planar imaging offers important benefits in patients who present with breast cancer and melanoma. These benefits include increased nodal detection, elimination of false positives and negatives and improved anatomical localization that ultimately aids and expedites surgical management. This has been demonstrated in the context of industrialized country previously and has now also been confirmed in the setting of a emerging-market nation.

A Structure-Adaptive Hybrid RBF-BP Classifier with an Optimized Learning Strategy

PubMed Central

Wen, Hui; Xie, Weixin; Pei, Jihong

2016-01-01

This paper presents a structure-adaptive hybrid RBF-BP (SAHRBF-BP) classifier with an optimized learning strategy. SAHRBF-BP is composed of a structure-adaptive RBF network and a BP network of cascade, where the number of RBF hidden nodes is adjusted adaptively according to the distribution of sample space, the adaptive RBF network is used for nonlinear kernel mapping and the BP network is used for nonlinear classification. The optimized learning strategy is as follows: firstly, a potential function is introduced into training sample space to adaptively determine the number of initial RBF hidden nodes and node parameters, and a form of heterogeneous samples repulsive force is designed to further optimize each generated RBF hidden node parameters, the optimized structure-adaptive RBF network is used for adaptively nonlinear mapping the sample space; then, according to the number of adaptively generated RBF hidden nodes, the number of subsequent BP input nodes can be determined, and the overall SAHRBF-BP classifier is built up; finally, different training sample sets are used to train the BP network parameters in SAHRBF-BP. Compared with other algorithms applied to different data sets, experiments show the superiority of SAHRBF-BP. Especially on most low dimensional and large number of data sets, the classification performance of SAHRBF-BP outperforms other training SLFNs algorithms. PMID:27792737

Large-scale seismic waveform quality metric calculation using Hadoop

DOE PAGES

Magana-Zook, Steven; Gaylord, Jessie M.; Knapp, Douglas R.; ...

2016-05-27

Here in this work we investigated the suitability of Hadoop MapReduce and Apache Spark for large-scale computation of seismic waveform quality metrics by comparing their performance with that of a traditional distributed implementation. The Incorporated Research Institutions for Seismology (IRIS) Data Management Center (DMC) provided 43 terabytes of broadband waveform data of which 5.1 TB of data were processed with the traditional architecture, and the full 43 TB were processed using MapReduce and Spark. Maximum performance of ~0.56 terabytes per hour was achieved using all 5 nodes of the traditional implementation. We noted that I/O dominated processing, and that I/Omore » performance was deteriorating with the addition of the 5th node. Data collected from this experiment provided the baseline against which the Hadoop results were compared. Next, we processed the full 43 TB dataset using both MapReduce and Apache Spark on our 18-node Hadoop cluster. We conducted these experiments multiple times with various subsets of the data so that we could build models to predict performance as a function of dataset size. We found that both MapReduce and Spark significantly outperformed the traditional reference implementation. At a dataset size of 5.1 terabytes, both Spark and MapReduce were about 15 times faster than the reference implementation. Furthermore, our performance models predict that for a dataset of 350 terabytes, Spark running on a 100-node cluster would be about 265 times faster than the reference implementation. We do not expect that the reference implementation deployed on a 100-node cluster would perform significantly better than on the 5-node cluster because the I/O performance cannot be made to scale. Finally, we note that although Big Data technologies clearly provide a way to process seismic waveform datasets in a high-performance and scalable manner, the technology is still rapidly changing, requires a high degree of investment in personnel, and will likely require significant changes in other parts of our infrastructure. Nevertheless, we anticipate that as the technology matures and third-party tool vendors make it easier to manage and operate clusters, Hadoop (or a successor) will play a large role in our seismic data processing.« less

Large-scale seismic waveform quality metric calculation using Hadoop

DOE Office of Scientific and Technical Information (OSTI.GOV)

Magana-Zook, Steven; Gaylord, Jessie M.; Knapp, Douglas R.

Here in this work we investigated the suitability of Hadoop MapReduce and Apache Spark for large-scale computation of seismic waveform quality metrics by comparing their performance with that of a traditional distributed implementation. The Incorporated Research Institutions for Seismology (IRIS) Data Management Center (DMC) provided 43 terabytes of broadband waveform data of which 5.1 TB of data were processed with the traditional architecture, and the full 43 TB were processed using MapReduce and Spark. Maximum performance of ~0.56 terabytes per hour was achieved using all 5 nodes of the traditional implementation. We noted that I/O dominated processing, and that I/Omore » performance was deteriorating with the addition of the 5th node. Data collected from this experiment provided the baseline against which the Hadoop results were compared. Next, we processed the full 43 TB dataset using both MapReduce and Apache Spark on our 18-node Hadoop cluster. We conducted these experiments multiple times with various subsets of the data so that we could build models to predict performance as a function of dataset size. We found that both MapReduce and Spark significantly outperformed the traditional reference implementation. At a dataset size of 5.1 terabytes, both Spark and MapReduce were about 15 times faster than the reference implementation. Furthermore, our performance models predict that for a dataset of 350 terabytes, Spark running on a 100-node cluster would be about 265 times faster than the reference implementation. We do not expect that the reference implementation deployed on a 100-node cluster would perform significantly better than on the 5-node cluster because the I/O performance cannot be made to scale. Finally, we note that although Big Data technologies clearly provide a way to process seismic waveform datasets in a high-performance and scalable manner, the technology is still rapidly changing, requires a high degree of investment in personnel, and will likely require significant changes in other parts of our infrastructure. Nevertheless, we anticipate that as the technology matures and third-party tool vendors make it easier to manage and operate clusters, Hadoop (or a successor) will play a large role in our seismic data processing.« less

Communication Characterization and Optimization of Applications Using Topology-Aware Task Mapping on Large Supercomputers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sreepathi, Sarat; D'Azevedo, Eduardo; Philip, Bobby

On large supercomputers, the job scheduling systems may assign a non-contiguous node allocation for user applications depending on available resources. With parallel applications using MPI (Message Passing Interface), the default process ordering does not take into account the actual physical node layout available to the application. This contributes to non-locality in terms of physical network topology and impacts communication performance of the application. In order to mitigate such performance penalties, this work describes techniques to identify suitable task mapping that takes the layout of the allocated nodes as well as the application's communication behavior into account. During the first phasemore » of this research, we instrumented and collected performance data to characterize communication behavior of critical US DOE (United States - Department of Energy) applications using an augmented version of the mpiP tool. Subsequently, we developed several reordering methods (spectral bisection, neighbor join tree etc.) to combine node layout and application communication data for optimized task placement. We developed a tool called mpiAproxy to facilitate detailed evaluation of the various reordering algorithms without requiring full application executions. This work presents a comprehensive performance evaluation (14,000 experiments) of the various task mapping techniques in lowering communication costs on Titan, the leadership class supercomputer at Oak Ridge National Laboratory.« less

The combination of preoperative PET/CT and sentinel lymph node biopsy in the surgical management of early-stage cervical cancer.

PubMed

Papadia, Andrea; Gasparri, Maria Luisa; Genoud, Sophie; Bernd, Klaeser; Mueller, Michael D

2017-11-01

The aim of the study was to evaluate the use of PET/CT and/or SLN mapping alone or in combination in cervical cancer patients. Data on stage IA1-IIA cervical cancer patients undergoing PET/CT and SLN mapping were retrospectively collected. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of PET/CT and SLN mapping, alone or in combination, in identifying cervical cancer patients with lymph node metastases were calculated. Sixty patients met the inclusion criteria. PET/CT showed a sensitivity of 68%, a specificity of 84%, a PPV of 61% and a NPV of 88% in detecting lymph nodal metastases. SLN mapping showed a sensitivity of 93%, a specificity of 100%, a PPV of 100% and a NPV of 97%. The combination of PET/CT and SLN mapping showed a sensitivity of 100%, a specificity of 86%, a PPV of 72% and a NPV of 100%. For patients with tumors of >2 cm in diameter, the PET/CT showed a sensitivity of 68%, a specificity of 72%, a PPV of 61% and a NPV of 86%. SLN mapping showed a sensitivity of 93%, a specificity of 100%, a PPV of 100% and a NPV of 95%. The combination of PET/CT and SLN mapping showed a sensitivity of 100%, a specificity of 76%, a PPV of 72% and a NPV of 100%. PET/CT represents a "safety net" that helps the surgeon in identifying metastatic lymph nodes, especially in patients with larger tumors.

Preoperative Sentinel Node Mapping in Sentinel Node Biopsy in Early Breast Cancers - Is It Cost-Effective?

PubMed

Co, Michael; Kwong, Ava

2017-04-01

Sentinel lymph node (SLN) biopsy is currently the gold standard of treatment in early breast cancers. Identification of SLNs by preoperative scintigraphy has been carried out to improve the detection of SLNs intraoperatively, but the evidence of its cost-effectiveness is lacking. Here, we analyze the cost-effectiveness of the utilization of scintigraphy in detection of SLNs. Clinical and operative details were retrieved from a prospectively maintained database. The resources and cost data from each patient who had undergone SLN biopsy with preoperative scintigraphy were retrieved. From January 2008 to December 2012, 400 patients underwent SLN biopsy for breast cancer. A total of 329 had preoperative SLN mapping with scintigraphy, Baseline patient demographic data for both arms were comparable. The relapse and recurrence rate of both arms were not statistically different. The detection rate of SLNs of both arms was the same (100%), and there were no grade 2 or above lymphedema in both groups of patients. However, the cost of each patient undergoing SLN mapping was USD $345.8. Preoperative SLN mapping does not improve the SLN detection rate. In addition, it does not affect the surgical outcomes in terms of complication, local relapse, and recurrence. The use of preoperative SLN mapping is no longer cost-effective. Copyright © 2016 Elsevier Inc. All rights reserved.

Network of dedicated processors for finding lowest-cost map path

NASA Technical Reports Server (NTRS)

Eberhardt, Silvio P. (Inventor)

1991-01-01

A method and associated apparatus are disclosed for finding the lowest cost path of several variable paths. The paths are comprised of a plurality of linked cost-incurring areas existing between an origin point and a destination point. The method comprises the steps of connecting a purality of nodes together in the manner of the cost-incurring areas; programming each node to have a cost associated therewith corresponding to one of the cost-incurring areas; injecting a signal into one of the nodes representing the origin point; propagating the signal through the plurality of nodes from inputs to outputs; reducing the signal in magnitude at each node as a function of the respective cost of the node; and, starting at one of the nodes representing the destination point and following a path having the least reduction in magnitude of the signal from node to node back to one of the nodes representing the origin point whereby the lowest cost path from the origin point to the destination point is found.

Patterns of regional head and neck lymph node metastasis in primary conjunctival malignant melanoma

PubMed Central

Lim, M; Tatla, T; Hersh, D; Hungerford, J

2006-01-01

Objective To correlate patterns of regional lymph node metastasis with the site of origin in primary conjunctival malignant melanoma. Design Retrospective analysis (1990–2003) of clinical data. Setting Two London tertiary referral centres. Participants 12 patients presenting with regional metastases after failed local treatment for conjunctival malignant melanoma. Results 6 cases predominantly involving the temporal conjunctiva metastasised to the pre‐auricular lymph nodes. Two cases predominantly involving the nasal conjunctiva metastasised to the submandibular nodes. Of the two cases with purely multifocal disease, one metastasised to the pre‐auricular nodes and another to both submandibular and parotid nodes. One primary conjunctival malignant melanoma had its origin in temporal conjunctiva but metastasised to submandibular nodes, and another case originating from nasal conjunctiva metastasised to pre‐auricular nodes. Conclusions Temporal conjunctival melanotic lesions tend to metastasise clinically to pre‐auricular lymph nodes and nasal conjunctival melanotic lesions metastasise to the submandibular lymph nodes. Patterns appear consistent with laboratory‐based anatomically mapped lymphatic drainage basins of the conjunctiva. PMID:16928703

Comparison of SPECT/CT and Planar Lympho-scintigraphy in Sentinel Node Biopsies of Oral Cavity Squamous Cell Carcinomas.

PubMed

Chandra, Piyush; Dhake, Sanket; Shah, Sneha; Agrawal, Archi; Purandare, Nilendu; Rangarajan, Venkatesh

2017-01-01

Evidence supporting the use of Sentinel node biopsy (SNB) for nodal staging of early oral squamous cell carcinomas (OSCC) appears to be very promising. Pre-operative lymphatic mapping using planar lymphoscinitigraphy (PL) with or without SPECT/CT in the SNB procedure is useful in sentinel node localization and for planning appropriate surgery. Recently, a large prospective multi-centric study evaluating SNB in cutaneous melanoma, breast and pelvic malignancies, demonstrated that adding SPECT to PL leads to surgical adjustments in a considerable number of patients. Our aim of this study was to evaluate the incremental value of additional SPECT/CT over PL alone in SNB for OSCC. This was a retrospective analysis of 44 patients (40- tongue, 4- buccal mucosa) with T1-T2, clinically N0 oral cavity SCC who underwent sentinel node biopsy procedure. PL and SPECT lymphoscinitigraphy images were compared for pre-operative mapping of sentinel nodes. Using a handheld gamma probe, a total of 179 sentinel nodes were harvested, with a mean of 4.06 per patient. PL revealed 75 hotspots with a mean of 1.70 per patient, and SPECT/CT revealed 92 hotspots with a mean of 2.09 per patient. Additional hotpots were identified in 14 patients on SPECT/CT, which included 4 patients, where PL did not detect any sentinel nodes. Pre-operative SPECT/CT in addition to planar lympho-scinitigraphy in sentinel node biopsies of oral cavity SCC detects more number of sentinel nodes compared to planar imaging alone. The higher sensitivity of SPECT combined with better anatomical localization using diagnostic CT may further improve the precision of SNB procedure.

Online Exhibits & Concept Maps

NASA Astrophysics Data System (ADS)

Douma, M.

2009-12-01

Presenting the complexity of geosciences to the public via the Internet poses a number of challenges. For example, utilizing various - and sometimes redundant - Web 2.0 tools can quickly devour limited time. Do you tweet? Do you write press releases? Do you create an exhibit or concept map? The presentation will provide participants with a context for utilizing Web 2.0 tools by briefly highlighting methods of online scientific communication across several dimensions. It will address issues of: * breadth and depth (e.g. from narrow topics to well-rounded views), * presentation methods (e.g. from text to multimedia, from momentary to enduring), * sources and audiences (e.g. for experts or for the public, content developed by producers to that developed by users), * content display (e.g. from linear to non-linear, from instructive to entertaining), * barriers to entry (e.g. from an incumbent advantage to neophyte accessible, from amateur to professional), * cost and reach (e.g. from cheap to expensive), and * impact (e.g. the amount learned, from anonymity to brand awareness). Against this backdrop, the presentation will provide an overview of two methods of online information dissemination, exhibits and concept maps, using the WebExhibits online museum (www.webexhibits.org) and SpicyNodes information visualization tool (www.spicynodes.org) as examples, with tips on how geoscientists can use either to communicate their science. Richly interactive online exhibits can serve to engage a large audience, appeal to visitors with multiple learning styles, prompt exploration and discovery, and present a topic’s breadth and depth. WebExhibits, which was among the first online museums, delivers interactive information, virtual experiments, and hands-on activities to the public. While large, multidisciplinary exhibits on topics like “Color Vision and Art” or “Calendars Through the Ages” require teams of scholars, user interface experts, professional writers and editors, teachers, artists, and web designers, a smaller scale collaborative effort can result in an effective mini-exhibit. Online concept maps can present a large quantity of information in bite-size chunks, demonstrating interrelationships between pieces of information without inundating visitors. SpicyNodes uses radial mapping technology to enable visitors to learn about a topic or search for information in intuitive and organic ways. This online concept mapping tool can be used as a portal to invite exploration into topics, or as a means of displaying hierarchies of information. With nodes that contain text, audio, video, and links, interactive online concept maps especially engage visual, kinesthetic, and nonlinear learners. SpicyNodes is also useful for scientists who wish to complement papers, chapters, and books with an online interface that is especially appealing to nonlinear learners. Essentially, SpicyNodes shifts the burden of discovery from the reader to the author. For example, the author may create a nodemap on climate change with hundreds of nodes, but as visitors drill through the nodemap for information (e.g. from climate change to atmospheric gases to carbon dioxide), they see only a few nodes at a time and are not overwhelmed.

Technical details of sentinel lymph node mapping in colorectal cancer and its impact on staging.

PubMed

Saha, S; Wiese, D; Badin, J; Beutler, T; Nora, D; Ganatra, B K; Desai, D; Kaushal, S; Nagaraju, M; Arora, M; Singh, T

2000-03-01

Sentinel lymph node (SLN) mapping for melanoma and breast cancer has greatly enhanced the identification of micrometastases in many patients, thereby upstaging a subset of these patients. The purpose of this study was to see if SLN mapping technique could be used to identify SLNs in colorectal cancer and to assess its impact on pathological staging and treatment. At the time of surgery, 1 ml of Lymphazurin 1% was injected subserosally around the tumor without injecting into the lumen. The first to fourth blue nodes identified were considered the SLNs, which have the highest probability to contain metastases. A standard oncological resection of the bowel was then performed. Multilevel microsections of the SLNs, including a detailed pathological examination of the entire specimen, was performed. SLN was successfully identified in 85 (98.8%) of 86 patients. In 85 patients, there were 1,367 (16 per patient) lymph nodes examined, of which 140 (1.6 per patient) were identified as SLNs. In 53 (95%) of 56, of whom the SLNs were without metastases (negative), all other non-SLNs also were negative. In 29 (34% of 85) patients, SLNs were positive for metastases; in 14 of the 29 patients, other non-SLNs also were positive in addition to the SLNs. In the other 15 of the 29 patients (18% of 85 patients), SLNs were the only site of metastases, and all other non-SLNs were negative. In 7 patients (8.2% of 85 patients), micrometastases were identified only in 1 or 2 of the 10 sections of a single SLN. In five of seven patients, such micrometastases were detected by hematoxylin and eosin staining and immunohistochemistry; in the other two patients, it was detected only by immunohistochemistry. In patients with negative SLNs, the rate of occurrence of micrometastases in non-SLNs was 5 (0.4%) of 1,184 lymph nodes. SLN mapping can be performed easily in colorectal cancer patients, with an accuracy of more than 95%. The identification of submicroscopic lymph node metastases by this technique may have upstaged these patients (18%) from stage I/II to stage III disease, who may then benefit from further adjuvant chemotherapy.

A Multi-Hop Clustering Mechanism for Scalable IoT Networks.

PubMed

Sung, Yoonyoung; Lee, Sookyoung; Lee, Meejeong

2018-03-23

It is expected that up to 26 billion Internet of Things (IoT) equipped with sensors and wireless communication capabilities will be connected to the Internet by 2020 for various purposes. With a large scale IoT network, having each node connected to the Internet with an individual connection may face serious scalability issues. The scalability problem of the IoT network may be alleviated by grouping the nodes of the IoT network into clusters and having a representative node in each cluster connect to the Internet on behalf of the other nodes in the cluster instead of having a per-node Internet connection and communication. In this paper, we propose a multi-hop clustering mechanism for IoT networks to minimize the number of required Internet connections. Specifically, the objective of proposed mechanism is to select the minimum number of coordinators, which take the role of a representative node for the cluster, i.e., having the Internet connection on behalf of the rest of the nodes in the cluster and to map a partition of the IoT nodes onto the selected set of coordinators to minimize the total distance between the nodes and their respective coordinator under a certain constraint in terms of maximum hop count between the IoT nodes and their respective coordinator. Since this problem can be mapped into a set cover problem which is known as NP-hard, we pursue a heuristic approach to solve the problem and analyze the complexity of the proposed solution. Through a set of experiments with varying parameters, the proposed scheme shows 63-87.3% reduction of the Internet connections depending on the number of the IoT nodes while that of the optimal solution is 65.6-89.9% in a small scale network. Moreover, it is shown that the performance characteristics of the proposed mechanism coincide with expected performance characteristics of the optimal solution in a large-scale network.

Lymphatic mapping and sentinel node identification in squamous cell carcinoma and melanoma of the head and neck.

PubMed

Tartaglione, G; Potenza, C; Caggiati, A; Maggiore, M; Gabrielli, F; Migliano, E; Pagan, M; Concolino, F; Ruatti, P

2002-01-01

The aim of our study was to evaluate the role of scintigraphy in lymphatic mapping and in the identification of the sentinel lymph node (SLN) in patients with head and neck cancer. Between September 1999 and February 2001 we enrolled 22 consecutive patients with cancer in the head and neck region: five squamous cell carcinomas, one Merkel cell tumor of the cheek, and 16 malignant melanomas. Lymphoscintigraphy was performed three hours before surgery after injection of 30-50 MBq of 99mTc -Nanocoll in 0.3 mL; the dose was fractionated by injecting the radiotracer at two points around the lesion. Static acquisition (anterior and/or lateral views, 512 x 512 matrix, 5 mins pre-set time) was started immediately after the injections so as to visualize the pathways of lymphatic drainage. The skin projection of the SLN was marked with ink. Intraoperative SLN detection was performed with perilesional injection of patent blue. SLNs were found with lymphoscintigraphy in all patients. Thirty-three SLNs were identified: one occipital node, three nodes at the base of the tongue, 10 superficial lateral nodes (external jugular), five submandibular nodes, five submental nodes, three mastoid nodes and six supraclavicular nodes. Biopsy was performed in 21/22 patients. In 20/22 patients the first lymph nodes were visualized in the proximal cranial regions (retroauricular, jugular and submandibular) at five minutes post injection. The SLN positivity rate was 13.6% (three patients). All patients with tumor-positive SLNs were submitted to radical dissection. Poor concordance in the detection of sentinel nodes was observed with patent blue. The flow of nanocolloid in the lymph vessels of the head is rapid. In our experience immediate scintigraphic imaging was essential to visualize the pathways of lymphatic drainage and the first SLN. Radioguided SLN biopsy is therefore recommended within three hours. Injection of patent blue is inadvisable because of the poor concordance with lymphoscintigraphy and the risk of permanent tattooing of the face.

Comparative evaluation of [(99m)tc]tilmanocept for sentinel lymph node mapping in breast cancer patients: results of two phase 3 trials.

PubMed

Wallace, Anne M; Han, Linda K; Povoski, Stephen P; Deck, Kenneth; Schneebaum, Schlomo; Hall, Nathan C; Hoh, Carl K; Limmer, Karl K; Krontiras, Helen; Frazier, Thomas G; Cox, Charles; Avisar, Eli; Faries, Mark; King, Dennis W; Christman, Lori; Vera, David R

2013-08-01

Sentinel lymph node (SLN) surgery is used worldwide for staging breast cancer patients and helps limit axillary lymph node dissection. [(99m)Tc]Tilmanocept is a novel receptor-targeted radiopharmaceutical evaluated in 2 open-label, nonrandomized, within-patient, phase 3 trials designed to assess the lymphatic mapping performance. A total of 13 centers contributed 148 patients with breast cancer. Each patient received [(99m)Tc]tilmanocept and vital blue dye (VBD). Lymph nodes identified intraoperatively as radioactive and/or blue stained were excised and histologically examined. The primary endpoint, concordance (lower boundary set point at 90 %), was the proportion of nodes detected by VBD and [(99m)Tc]tilmanocept. A total of 13 centers contributed 148 patients who were injected with both agents. Intraoperatively, 207 of 209 nodes detected by VBD were also detected by [(99m)Tc]tilmanocept for a concordance rate of 99.04 % (p < 0.0001). [(99m)Tc]tilmanocept detected a total of 320 nodes, of which 207 (64.7 %) were detected by VBD. [(99m)Tc]Tilmanocept detected at least 1 SLN in more patients (146) than did VBD (131, p < 0.0001). In 129 of 131 patients with ≥1 blue node, all blue nodes were radioactive. Of 33 pathology-positive nodes (18.2 % patient pathology rate), [(99m)Tc]tilmanocept detected 31 of 33, whereas VBD detected only 25 of 33 (p = 0.0312). No pathology-positive SLNs were detected exclusively by VBD. No serious adverse events were attributed to [(99m)Tc]tilmanocept. [(99m)Tc]Tilmanocept demonstrated success in detecting a SLN while meeting the primary endpoint. Interestingly, [(99m)Tc]tilmanocept was additionally noted to identify more SLNs in more patients. This localization represented a higher number of metastatic breast cancer lymph nodes than that of VBD.

A Multi-Hop Clustering Mechanism for Scalable IoT Networks

PubMed Central

2018-01-01

It is expected that up to 26 billion Internet of Things (IoT) equipped with sensors and wireless communication capabilities will be connected to the Internet by 2020 for various purposes. With a large scale IoT network, having each node connected to the Internet with an individual connection may face serious scalability issues. The scalability problem of the IoT network may be alleviated by grouping the nodes of the IoT network into clusters and having a representative node in each cluster connect to the Internet on behalf of the other nodes in the cluster instead of having a per-node Internet connection and communication. In this paper, we propose a multi-hop clustering mechanism for IoT networks to minimize the number of required Internet connections. Specifically, the objective of proposed mechanism is to select the minimum number of coordinators, which take the role of a representative node for the cluster, i.e., having the Internet connection on behalf of the rest of the nodes in the cluster and to map a partition of the IoT nodes onto the selected set of coordinators to minimize the total distance between the nodes and their respective coordinator under a certain constraint in terms of maximum hop count between the IoT nodes and their respective coordinator. Since this problem can be mapped into a set cover problem which is known as NP-hard, we pursue a heuristic approach to solve the problem and analyze the complexity of the proposed solution. Through a set of experiments with varying parameters, the proposed scheme shows 63–87.3% reduction of the Internet connections depending on the number of the IoT nodes while that of the optimal solution is 65.6–89.9% in a small scale network. Moreover, it is shown that the performance characteristics of the proposed mechanism coincide with expected performance characteristics of the optimal solution in a large-scale network. PMID:29570691

The Japan Lung Cancer Society-Japanese Society for Radiation Oncology consensus-based computed tomographic atlas for defining regional lymph node stations in radiotherapy for lung cancer.

PubMed

Itazawa, Tomoko; Tamaki, Yukihisa; Komiyama, Takafumi; Nishimura, Yasumasa; Nakayama, Yuko; Ito, Hiroyuki; Ohde, Yasuhisa; Kusumoto, Masahiko; Sakai, Shuji; Suzuki, Kenji; Watanabe, Hirokazu; Asamura, Hisao

2017-01-01

The purpose of this study was to develop a consensus-based computed tomographic (CT) atlas that defines lymph node stations in radiotherapy for lung cancer based on the lymph node map of the International Association for the Study of Lung Cancer (IASLC). A project group in the Japanese Radiation Oncology Study Group (JROSG) initially prepared a draft of the atlas in which lymph node Stations 1-11 were illustrated on axial CT images. Subsequently, a joint committee of the Japan Lung Cancer Society (JLCS) and the Japanese Society for Radiation Oncology (JASTRO) was formulated to revise this draft. The committee consisted of four radiation oncologists, four thoracic surgeons and three thoracic radiologists. The draft prepared by the JROSG project group was intensively reviewed and discussed at four meetings of the committee over several months. Finally, we proposed definitions for the regional lymph node stations and the consensus-based CT atlas. This atlas was approved by the Board of Directors of JLCS and JASTRO. This resulted in the first official CT atlas for defining regional lymph node stations in radiotherapy for lung cancer authorized by the JLCS and JASTRO. In conclusion, the JLCS-JASTRO consensus-based CT atlas, which conforms to the IASLC lymph node map, was established. © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

GATE Monte Carlo simulation of dose distribution using MapReduce in a cloud computing environment.

PubMed

Liu, Yangchuan; Tang, Yuguo; Gao, Xin

2017-12-01

The GATE Monte Carlo simulation platform has good application prospects of treatment planning and quality assurance. However, accurate dose calculation using GATE is time consuming. The purpose of this study is to implement a novel cloud computing method for accurate GATE Monte Carlo simulation of dose distribution using MapReduce. An Amazon Machine Image installed with Hadoop and GATE is created to set up Hadoop clusters on Amazon Elastic Compute Cloud (EC2). Macros, the input files for GATE, are split into a number of self-contained sub-macros. Through Hadoop Streaming, the sub-macros are executed by GATE in Map tasks and the sub-results are aggregated into final outputs in Reduce tasks. As an evaluation, GATE simulations were performed in a cubical water phantom for X-ray photons of 6 and 18 MeV. The parallel simulation on the cloud computing platform is as accurate as the single-threaded simulation on a local server and the simulation correctness is not affected by the failure of some worker nodes. The cloud-based simulation time is approximately inversely proportional to the number of worker nodes. For the simulation of 10 million photons on a cluster with 64 worker nodes, time decreases of 41× and 32× were achieved compared to the single worker node case and the single-threaded case, respectively. The test of Hadoop's fault tolerance showed that the simulation correctness was not affected by the failure of some worker nodes. The results verify that the proposed method provides a feasible cloud computing solution for GATE.

Lymphatic Territories (Lymphosomes) in the Rat: An Anatomical Study for Future Lymphatic Research.

PubMed

Suami, Hiroo; Scaglioni, Mario F

2017-11-01

Understanding the precise anatomy in experimental animals is crucial for correct design of research projects. Rats are commonly used for scientific research in plastic surgery because of their availability in academic institutions, moderate cost, and sizable vessels for microsurgical procedures. In past publications about rat anatomy, lymphatic mapping has been limited and incomplete. The aim of this study was to comprehensively map the superficial lymphatic system in the rat. Twenty-seven Sprague-Dawley rats were used for this study. Indocyanine green fluorescence lymphography was used to identify the lymphatic vessels and lymph nodes. Under general anaesthesia, indocyanine green was injected intradermally at multiple spots along the dorsal and medial midlines, front and hind paws, ears, and tail. The course of the lymphatic vessels was traced on the skin with a marker pen and photographed. The superficial lymphatic vessels in each rat were sketched on a graphic template and all of the templates were superimposed using graphics software to define the relationship between the lymphatic vessel and sentinel node. Indocyanine green fluorescence lymphography was able to demonstrate the superficial lymphatic vessels in the rat. Six groups of regional lymph node/s were identified and lymphatic pathways to those nodes delineated. The authors' lymphosome concept was successfully applied to the rat, with six lymphosomes identified. The authors succeeded in performing superficial lymphatic mapping in the rat. The authors' anatomical findings can provide further information about the lymphatic system in the normal state and promote understanding of pathologic changes generated by surgical manipulation for future studies.

Scanning laser vibrometry and luminol photomicrography to map cavitational activity around ultrasonic scalers

NASA Astrophysics Data System (ADS)

Felver, Bernhard; King, David C.; Lea, Simon C.; Price, Gareth J.; Walmsley, A. Damien

2008-06-01

Ultrasonic dental scalers are clinically used to remove deposits from tooth surfaces. A metal probe, oscillating at ultrasonic frequencies, is used to chip away deposits from the teeth. To reduce frictional heating, water flows over the operated probe in which a bi-product, cavitation, may be generated. The aim of this study is characterise probe oscillations using scanning laser vibrometry and to relate the recorded data to the occurrence of cavitation that is mapped in the course of this research. Scanning laser vibrometry (Polytec models 300-F/S and 400-3D) was used to measure the movement of various designs of operating probes and to locate vibration nodes / anti-nodes at different generator power settings and contact loads (100g and 200g). Cavitation mapping was performed by photographing the emission from a luminol solution with a digital camera (Artemis ICX285). The scaler design influences the number and location of vibration node / anti-node points. For all ultrasonic probes, the highest displacement amplitude values were recorded at the tip. The highest amounts of cavitation around the probes were recorded at the second anti-node measured from the tip. Broad, beaver-tale shaped probes produced more cavitation than slim shaped ones. The design also influences the amount of inertial cavitation around the operated instrument. The clinical relevance is that broad, beaver-tale shaped probes are unlikely to reach subgingival areas of the tooth. Further research is required to design probes that will be clinically superior to cleaning this area of the tooth.

Sentinel lymph node mapping in melanoma with technetium-99m dextran.

PubMed

Neubauer, S; Mena, I; Iglesis, R; Schwartz, R; Acevedo, J C; Leon, A; Gomez, L

2001-06-01

The aim of this work is to evaluate the capability of Tc99m B Dextran as a lymphoscintigraphic agent in the detection of the sentinel node in skin lesions. Forty-one patients with melanomas (39) and Merkel cell tumors (2) had perilesional intradermal injection of Tc99m-Dextran 2 hours before surgery. Serial gamma camera images and a handheld gamma probe were used to direct sentinel node biopsy. In 39/41 patients, lymph channels and 52 sentinel nodes (one to three sentinel nodes/patient) could be visualized. In one patient, with a dorsal melanoma, no lymph channels or lymph nodes could be demonstrated on the images and only minimal radioactivity was found in the regional nodes with the probe. Another patient with a facial lesion failed to demonstrate lymph channels or nodes. No adverse reactions were observed. Tc99m-Dextran provided good definition of lymph channels and sentinel node localization, without the risks related to the use of potentially hazardous labeled materials of biological origin.

Effects of Concept Mapping on Creativity in Photo Stories

ERIC Educational Resources Information Center

Simper, Natalie; Reeve, Richard; Kirby, J. R.

2016-01-01

This research tested the use of concept map planning to support the development of creativity in photo stories, hypothesizing that skills taught to support organization would improve creativity. Concept maps are a type of graphic organizer, used to represent an ordering of ideas with nodes and linking words that form propositional statements. They…

An Investigation of the Value of Using Concept Maps in General Chemistry.

ERIC Educational Resources Information Center

Nicoll, Gayle; Francisco, Joseph; Nakhleh, Mary B.

2001-01-01

Reports on a qualitative investigation of the effects of integrating concept maps into freshman-level general chemistry curriculum. Indicates that students in the experimental section had significantly more links and nodes in their concept maps than students in the traditional section. There were no significant differences between the two sections…

Robot Acquisition of Active Maps Through Teleoperation and Vector Space Analysis

NASA Technical Reports Server (NTRS)

Peters, Richard Alan, II

2003-01-01

The work performed under this contract was in the area of intelligent robotics. The problem being studied was the acquisition of intelligent behaviors by a robot. The method was to acquire action maps that describe tasks as sequences of reflexive behaviors. Action maps (a.k.a. topological maps) are graphs whose nodes represent sensorimotor states and whose edges represent the motor actions that cause the robot to proceed from one state to the next. The maps were acquired by the robot after being teleoperated or otherwise guided by a person through a task several times. During a guided task, the robot records all its sensorimotor signals. The signals from several task trials are partitioned into episodes of static behavior. The corresponding episodes from each trial are averaged to produce a task description as a sequence of characteristic episodes. The sensorimotor states that indicate episode boundaries become the nodes, and the static behaviors, the edges. It was demonstrated that if compound maps are constructed from a set of tasks then the robot can perform new tasks in which it was never explicitly trained.

Radiolabeling of Cramoll 1,4: Evaluation of the Biodistribution

PubMed Central

Ferreira de Carvalho Patricio, Beatriz; Lima-Ribeiro, Maria Helena Madruga; Correia, Maria Tereza dos Santos; Carneiro-Leão, Ana Maria dos Anjos; Albernaz, Marta de Souza; Barboza, Thiago; de Souza, Sergio Augusto Lopes; Santos-Oliveira, Ralph

2011-01-01

The cramoll 1,4 is a well-studied lectin. However, few studies about its biodistribution have been done before. In this study, we radiolabeled the cramol 1,4 with Tc-99m and analyzed the biodistribution. The results showed that the cramol has an abnormal uptake by the bowel with reflections on its clearance mechanism. PMID:21760823

Aligning Metabolic Pathways Exploiting Binary Relation of Reactions.

PubMed

Huang, Yiran; Zhong, Cheng; Lin, Hai Xiang; Huang, Jing

2016-01-01

Metabolic pathway alignment has been widely used to find one-to-one and/or one-to-many reaction mappings to identify the alternative pathways that have similar functions through different sets of reactions, which has important applications in reconstructing phylogeny and understanding metabolic functions. The existing alignment methods exhaustively search reaction sets, which may become infeasible for large pathways. To address this problem, we present an effective alignment method for accurately extracting reaction mappings between two metabolic pathways. We show that connected relation between reactions can be formalized as binary relation of reactions in metabolic pathways, and the multiplications of zero-one matrices for binary relations of reactions can be accomplished in finite steps. By utilizing the multiplications of zero-one matrices for binary relation of reactions, we efficiently obtain reaction sets in a small number of steps without exhaustive search, and accurately uncover biologically relevant reaction mappings. Furthermore, we introduce a measure of topological similarity of nodes (reactions) by comparing the structural similarity of the k-neighborhood subgraphs of the nodes in aligning metabolic pathways. We employ this similarity metric to improve the accuracy of the alignments. The experimental results on the KEGG database show that when compared with other state-of-the-art methods, in most cases, our method obtains better performance in the node correctness and edge correctness, and the number of the edges of the largest common connected subgraph for one-to-one reaction mappings, and the number of correct one-to-many reaction mappings. Our method is scalable in finding more reaction mappings with better biological relevance in large metabolic pathways.

In vivo biodistribution and behavior of CdTe/ZnS quantum dots.

PubMed

Zhao, Yan; Zhang, Yue; Qin, Gaofeng; Cheng, Jinjun; Zeng, Wenhao; Liu, Shuchen; Kong, Hui; Wang, Xueqian; Wang, Qingguo; Qu, Huihua

2017-01-01

The unique features of quantum dots (QDs) make them desirable fluorescent tags for cell and developmental biology applications that require long-term, multitarget, and highly sensitive imaging. In this work, we imaged fluorescent cadmium telluride/zinc sulfide (CdTe/ZnS) QDs in organs, tissues, and cells, and analyzed the mechanism of their lymphatic uptake and cellular distribution. We observed that the fluorescent CdTe/ZnS QDs were internalized by lymph nodes in four cell lines from different tissue sources. We obtained the fluorescence intensity-QD concentrations curve by quantitative analysis. Our results demonstrate that cells containing QDs can complete mitosis normally and that distribution of QDs was uniform across cell types and involved the vesicular transport system, including the endoplasmic reticulum. This capacity for CdTe/ZnS QD targeting provides insights into the applicability and limitations of fluorescent QDs for imaging biological specimens.

Lymphoscintigraphy and SPECT/CT in multicentric and multifocal breast cancer: does each tumour have a separate drainage pattern? Results of a Dutch multicentre study (MULTISENT).

PubMed

Brouwer, O R; Vermeeren, L; van der Ploeg, I M C; Valdés Olmos, R A; Loo, C E; Pereira-Bouda, L M; Smit, F; Neijenhuis, P; Vrouenraets, B C; Sivro-Prndelj, F; Jap-a-Joe, S M; Borgstein, P J; Rutgers, E J Th; Oldenburg, H S A

2012-07-01

To investigate whether lymphoscintigraphy and SPECT/CT after intralesional injection of radiopharmaceutical into each tumour separately in patients with multiple malignancies in one breast yields additional sentinel nodes compared to intralesional injection of the largest tumour only. Patients were included prospectively at four centres in The Netherlands. Lymphatic flow was studied using planar lymphoscintigraphy and SPECT/CT until 4 h after administration of (99m)Tc-nanocolloid in the largest tumour. Subsequently, the smaller tumour(s) was injected intratumorally followed by the same imaging sequence. Sentinel nodes were intraoperatively localized using a gamma ray detection probe and vital blue dye. Included in the study were 50 patients. Additional lymphatic drainage was depicted after the second and/or third injection in 32 patients (64%). Comparison of planar images and SPECT/CT images after consecutive injections enabled visualization of the number and location of additional sentinel nodes (32 axillary, 11 internal mammary chain, 2 intramammary, and 1 interpectoral. A sentinel node contained metastases in 17 patients (34%). In five patients with a tumour-positive node in the axilla that was visualized after the first injection, an additional involved axillary node was found after the second injection. In two patients, isolated tumour cells were found in sentinel nodes that were only visualized after the second injection, whilst the sentinel nodes identified after the first injection were tumour-negative. Lymphoscintigraphy and SPECT/CT after consecutive intratumoral injections of tracer enable lymphatic mapping of each tumour separately in patients with multiple malignancies within one breast. The high incidence of additional sentinel nodes draining from tumours other than the largest one suggests that separate tumour-related tracer injections may be a more accurate approach to mapping and sampling of sentinel nodes in patients with multicentric or multifocal breast cancer.

Comparison of Node-Centered and Cell-Centered Unstructured Finite-Volume Discretizations. Part 1; Viscous Fluxes

NASA Technical Reports Server (NTRS)

Diskin, Boris; Thomas, James L.; Nielsen, Eric J.; Nishikawa, Hiroaki; White, Jeffery A.

2009-01-01

Discretization of the viscous terms in current finite-volume unstructured-grid schemes are compared using node-centered and cell-centered approaches in two dimensions. Accuracy and efficiency are studied for six nominally second-order accurate schemes: a node-centered scheme, cell-centered node-averaging schemes with and without clipping, and cell-centered schemes with unweighted, weighted, and approximately mapped least-square face gradient reconstruction. The grids considered range from structured (regular) grids to irregular grids composed of arbitrary mixtures of triangles and quadrilaterals, including random perturbations of the grid points to bring out the worst possible behavior of the solution. Two classes of tests are considered. The first class of tests involves smooth manufactured solutions on both isotropic and highly anisotropic grids with discontinuous metrics, typical of those encountered in grid adaptation. The second class concerns solutions and grids varying strongly anisotropically over a curved body, typical of those encountered in high-Reynolds number turbulent flow simulations. Results from the first class indicate the face least-square methods, the node-averaging method without clipping, and the node-centered method demonstrate second-order convergence of discretization errors with very similar accuracies per degree of freedom. The second class of tests are more discriminating. The node-centered scheme is always second order with an accuracy and complexity in linearization comparable to the best of the cell-centered schemes. In comparison, the cell-centered node-averaging schemes are less accurate, have a higher complexity in linearization, and can fail to converge to the exact solution when clipping of the node-averaged values is used. The cell-centered schemes using least-square face gradient reconstruction have more compact stencils with a complexity similar to the complexity of the node-centered scheme. For simulations on highly anisotropic curved grids, the least-square methods have to be amended either by introducing a local mapping of the surface anisotropy or modifying the scheme stencil to reflect the direction of strong coupling.

The history of sentinel node biopsy in head and neck cancer: From visualization of lymphatic vessels to sentinel nodes.

PubMed

de Bree, Remco; Nieweg, Omgo E

2015-09-01

The aim of this report is to describe the history of sentinel node biopsy in head and neck cancer. Sentinel node biopsy is a minimally invasive technique to select patients for treatment of metastatic lymph nodes in the neck. Although this procedure has only recently been accepted for early oral cancer, the first studies on visualization of the cervical lymphatic vessels were reported in the 1960s. In the 1980s mapping of lymphatic drainage from specific head and neck sites was introduced. Sentinel node biopsy was further developed in the 1990s and after validation in this century the procedure is routinely performed in early oral cancer in several head and neck centers. New techniques may improve the accuracy of sentinel node biopsy further, particularly in difficult subsites like the floor of mouth. Copyright © 2015 Elsevier Ltd. All rights reserved.

Impact of same day vs day before pre-operative lymphoscintigraphy for sentinel lymph node biopsy for early breast cancer (local Australian experience).

PubMed

Huang, Yang Yang; Maurel, Amelie; Hamza, Saud; Jackson, Lee; Al-Ogaili, Zeyad

2018-06-01

To assess the impact of delayed vs immediate pre-operative lymphoscintigraphy (LSG) for sentinel lymph node biopsy in a single Australian tertiary breast cancer centre. Retrospective cohort study analysing patients with breast cancer or DCIS who underwent lumpectomy or mastectomy with pre-operative LSG and intra-operative sentinel lymph node biopsy from January 2015 to June 2016. A total of 182 LSG were performed. Group A patients had day before pre-operative LSG mapping (n = 79) and Group B had LSG mapping on the day of surgery (n = 103). The overall LSG localisation rate was 97.3% and no statistical difference was detected between the two groups. The overall sentinel lymph node biopsies (SLN) were identified in 99.6% of patients. The number of nodes excised was slightly higher in Group A (1.90 vs 1.72); however, this was not statistically significant. In addition, the number of nodes on histopathology and the incidence of second echelon nodal detection were also similar between the two groups without statistical significance. In conclusion, the 2-day LSG protocol had no impact on overall SLNB and LSG detection rates although slightly higher second tier nodes but this did not translate to any difference between the number of harvest nodes between the two groups. The 2-day LSG allows for greater flexibility in theatre planning and more efficient use of theatre time. We recommend a dose of 40 Mbq of Tc99 m pertechnetate-labelled colloid be given day prior to surgery within a 24-hour timeframe. © 2017 The Royal Australian and New Zealand College of Radiologists.

Near-Infrared Lymphatic Mapping of the Recurrent Laryngeal Nerve Nodes in T1 Esophageal Cancer.

PubMed

Park, Seong Yong; Suh, Jee Won; Kim, Dae Joon; Park, Jun Chul; Kim, Eun Hye; Lee, Chang Young; Lee, Jin Gu; Paik, Hyo Chae; Chung, Kyoung Young

2018-06-01

It is still unclear that dissection of recurrent laryngeal nerve nodes is mandatory in patients with cT1 middle or lower thoracic esophageal squamous cell carcinoma when the nodes are negative in preoperative staging workup. We aimed to evaluate the feasibility of near-infrared image-guided lymphatic mapping of bilateral recurrent laryngeal nerve nodes. The day before operation, we injected indocyanine green (ICG) into the submucosal layer by endoscopy. At the time of upper mediastinal dissection, ICG-stained basins were identified along the bilateral recurrent laryngeal nerves and retrieved under guidance of the Firefly system. After the operation, remnant ICG-unstained basins were dissected from the specimen to assess the presence of metastasis. Of 29 patients enrolled, ICG-stained basins could be identified in 25 patients (86.2%), and 6 of them (24.0%) had nodal metastasis; 4 in the right recurrent laryngeal nerve chain, 1 in the left recurrent laryngeal nerve chain, and 1 in both recurrent laryngeal nerve chains. On pathologic examination of 345 recurrent laryngeal nerve nodes, two metastatic nodes were identified in ICG-unstained basins along the left recurrent laryngeal nerve in a patient who had lymph node metastases in ICG-stained basins along both recurrent laryngeal nerves. Negative predictive value in detection of nodal metastasis was 100% for the right recurrent laryngeal nerve chain and 98.2% for the left recurrent laryngeal nerve chain. Real-time assessment of recurrent laryngeal nerve nodes with near-infrared image was technically feasible, and we could detect lymphatic basins that most likely have nodal metastasis. Our technique might be useful in determining the optimal extent of lymphadenectomy. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Predicting axillary lymph node metastasis from kinetic statistics of DCE-MRI breast images

NASA Astrophysics Data System (ADS)

Ashraf, Ahmed B.; Lin, Lilie; Gavenonis, Sara C.; Mies, Carolyn; Xanthopoulos, Eric; Kontos, Despina

2012-03-01

The presence of axillary lymph node metastases is the most important prognostic factor in breast cancer and can influence the selection of adjuvant therapy, both chemotherapy and radiotherapy. In this work we present a set of kinetic statistics derived from DCE-MRI for predicting axillary node status. Breast DCE-MRI images from 69 women with known nodal status were analyzed retrospectively under HIPAA and IRB approval. Axillary lymph nodes were positive in 12 patients while 57 patients had no axillary lymph node involvement. Kinetic curves for each pixel were computed and a pixel-wise map of time-to-peak (TTP) was obtained. Pixels were first partitioned according to the similarity of their kinetic behavior, based on TTP values. For every kinetic curve, the following pixel-wise features were computed: peak enhancement (PE), wash-in-slope (WIS), wash-out-slope (WOS). Partition-wise statistics for every feature map were calculated, resulting in a total of 21 kinetic statistic features. ANOVA analysis was done to select features that differ significantly between node positive and node negative women. Using the computed kinetic statistic features a leave-one-out SVM classifier was learned that performs with AUC=0.77 under the ROC curve, outperforming the conventional kinetic measures, including maximum peak enhancement (MPE) and signal enhancement ratio (SER), (AUCs of 0.61 and 0.57 respectively). These findings suggest that our DCE-MRI kinetic statistic features can be used to improve the prediction of axillary node status in breast cancer patients. Such features could ultimately be used as imaging biomarkers to guide personalized treatment choices for women diagnosed with breast cancer.

Highly designable phenotypes and mutational buffers emerge from a systematic mapping between network topology and dynamic output.

PubMed

Nochomovitz, Yigal D; Li, Hao

2006-03-14

Deciphering the design principles for regulatory networks is fundamental to an understanding of biological systems. We have explored the mapping from the space of network topologies to the space of dynamical phenotypes for small networks. Using exhaustive enumeration of a simple model of three- and four-node networks, we demonstrate that certain dynamical phenotypes can be generated by an atypically broad spectrum of network topologies. Such dynamical outputs are highly designable, much like certain protein structures can be designed by an unusually broad spectrum of sequences. The network topologies that encode a highly designable dynamical phenotype possess two classes of connections: a fully conserved core of dedicated connections that encodes the stable dynamical phenotype and a partially conserved set of variable connections that controls the transient dynamical flow. By comparing the topologies and dynamics of the three- and four-node network ensembles, we observe a large number of instances of the phenomenon of "mutational buffering," whereby addition of a fourth node suppresses phenotypic variation amongst a set of three-node networks.

A strategy to rotate the Mars Observer orbit node line to advance the mapping schedule

NASA Technical Reports Server (NTRS)

Pernicka, Henry J.; Sweetser, Theodore H.; Roncoli, Ralph B.

1993-01-01

The Mars Observer (MO) spacecraft was successfully launched on September 25, 1992 and will arrive at Mars on August 24, 1993. At Mars, the spacecraft will study the planet's surface, atmosphere, and gravitational and magnetic fields. In order to achieve these scientific objectives, MO will be placed in a 2 PM (descending node) sun-synchronous orbit. Upon arrival at Mars, however, the longitude of the descending node will be approximately 15 deg greater than the desired value. The baseline plan requires a 59 day `waiting' period for the correct solar orientation to occur. During this period, 28 days are required for scientific experimentation but the remaining 30.6 days potentially could be eliminated. The strategy developed in this study examined the possibility of using any `excess' Delta-V available at Mars arrival to rotate the node line to the desired value and thus allow mapping to begin earlier. A preliminary analysis completed prior to launch is described that examined the entire launch period including the required Delta-V to perform the needed nodal rotation. A more detailed study performed after launch is also summarized.

Binocular Goggle Augmented Imaging and Navigation System provides real-time fluorescence image guidance for tumor resection and sentinel lymph node mapping

NASA Astrophysics Data System (ADS)

B. Mondal, Suman; Gao, Shengkui; Zhu, Nan; Sudlow, Gail P.; Liang, Kexian; Som, Avik; Akers, Walter J.; Fields, Ryan C.; Margenthaler, Julie; Liang, Rongguang; Gruev, Viktor; Achilefu, Samuel

2015-07-01

The inability to identify microscopic tumors and assess surgical margins in real-time during oncologic surgery leads to incomplete tumor removal, increases the chances of tumor recurrence, and necessitates costly repeat surgery. To overcome these challenges, we have developed a wearable goggle augmented imaging and navigation system (GAINS) that can provide accurate intraoperative visualization of tumors and sentinel lymph nodes in real-time without disrupting normal surgical workflow. GAINS projects both near-infrared fluorescence from tumors and the natural color images of tissue onto a head-mounted display without latency. Aided by tumor-targeted contrast agents, the system detected tumors in subcutaneous and metastatic mouse models with high accuracy (sensitivity = 100%, specificity = 98% ± 5% standard deviation). Human pilot studies in breast cancer and melanoma patients using a near-infrared dye show that the GAINS detected sentinel lymph nodes with 100% sensitivity. Clinical use of the GAINS to guide tumor resection and sentinel lymph node mapping promises to improve surgical outcomes, reduce rates of repeat surgery, and improve the accuracy of cancer staging.

An optimization method of VON mapping for energy efficiency and routing in elastic optical networks

NASA Astrophysics Data System (ADS)

Liu, Huanlin; Xiong, Cuilian; Chen, Yong; Li, Changping; Chen, Derun

2018-03-01

To improve resources utilization efficiency, network virtualization in elastic optical networks has been developed by sharing the same physical network for difference users and applications. In the process of virtual nodes mapping, longer paths between physical nodes will consume more spectrum resources and energy. To address the problem, we propose a virtual optical network mapping algorithm called genetic multi-objective optimize virtual optical network mapping algorithm (GM-OVONM-AL), which jointly optimizes the energy consumption and spectrum resources consumption in the process of virtual optical network mapping. Firstly, a vector function is proposed to balance the energy consumption and spectrum resources by optimizing population classification and crowding distance sorting. Then, an adaptive crossover operator based on hierarchical comparison is proposed to improve search ability and convergence speed. In addition, the principle of the survival of the fittest is introduced to select better individual according to the relationship of domination rank. Compared with the spectrum consecutiveness-opaque virtual optical network mapping-algorithm and baseline-opaque virtual optical network mapping algorithm, simulation results show the proposed GM-OVONM-AL can achieve the lowest bandwidth blocking probability and save the energy consumption.

Radiofrequency Electromagnetic Field Map of Timisoara

NASA Astrophysics Data System (ADS)

Stefu, N.; Solyom, I.; Arama, A.

2015-12-01

There are many electromagnetic field (EMF) sources nowadays acting simultaneously, especially in urban areas, making the theoretical estimation of electromagnetic power at ground level very difficult. This paper reports on EMF maps built with measurements collected in Timisoara, at various radiofrequencies. A grid of 15×15 squares was built (approximate resolution 400m x 400m) and measurements of the average and maximum values of the electric field E, magnetic field H and total power density S at 0.9, 1.8 and 2.4 GHz were collected in every node of the grid. Positions of the nodes in terms of latitude and longitude were also collected. Maps were built presenting the spatial distribution of the measured quantities over Timisoara. Potential influences of EMF on public health are discussed.

Scaffold explorer: an interactive tool for organizing and mining structure-activity data spanning multiple chemotypes.

PubMed

Agrafiotis, Dimitris K; Wiener, John J M

2010-07-08

We introduce Scaffold Explorer, an interactive tool that allows medicinal chemists to define hierarchies of chemical scaffolds and use them to explore their project data. Scaffold Explorer allows the user to construct a tree, where each node corresponds to a specific scaffold. Each node can have multiple children, each of which represents a more refined substructure relative to its parent node. Once the tree is defined, it can be mapped onto any collection of compounds and be used as a navigational tool to explore structure-activity relationships (SAR) across different chemotypes. The rich visual analytics of Scaffold Explorer afford the user a "bird's-eye" view of the chemical space spanned by a particular data set, map any physicochemical property or biological activity of interest onto the individual scaffold nodes, serve as an aggregator for the properties of the compounds represented by these nodes, and quickly distinguish promising chemotypes from less interesting or problematic ones. Unlike previous approaches, which focused on automated extraction and classification of scaffolds, the utility of the new tool rests on its interactivity and ability to accommodate the medicinal chemists' intuition by allowing the use of arbitrary substructures containing variable atoms, bonds, and/or substituents such as those employed in substructure search.

Animated and Static Concept Maps Enhance Learning from Spoken Narration

ERIC Educational Resources Information Center

Adesope, Olusola O.; Nesbit, John C.

2013-01-01

An animated concept map represents verbal information in a node-link diagram that changes over time. The goals of the experiment were to evaluate the instructional effects of presenting an animated concept map concurrently with semantically equivalent spoken narration. The study used a 2 x 2 factorial design in which an animation factor (animated…

Limited effectiveness of patent blue dye in addition to isotope scanning for identification of sentinel lymph nodes: Cross-sectional real-life study in 1024 breast cancer patients.

PubMed

Rauch, Philippe; Merlin, Jean-Louis; Leufflen, Lea; Salleron, Julia; Harlé, Alexandre; Olivier, Pierre; Marchal, Frédéric

2016-09-01

Although morbidity is reduced when sentinel lymph node (SLN) biopsy is performed with dual isotopic and blue dye identification, the effectiveness of adding blue dye to radioisotope remains debated because side effects including anaphylactic reactions. Using data from a prospectively maintained database, 1884 lymph node-negative breast cancer patients who underwent partial mastectomy with SLN mapping by a dual-tracer using patent blue dye (PBD) and radioisotope were retrospectively studied between January 2000 and July 2013. Patients with tumors <3 cm and with >1 node detected by one of the two techniques (N = 1024) were included in this real-life cross-sectional study. Among the 1024 patients, 274 had positive SLN detected by isotopic and/or PBD staining. Only 4 patients having no detectable radioactivity in the axilla had SLN identified only by PBD staining (blue-only) while 26 patients had SLN only identified by isotopic detection (hot-only) illustrating failure rates of 9.5% (26/274) and 1.5% (4/274), respectively. Among these four patients, two had negative lymphoscintigraphy. Therefore, the contribution of PBD to metastatic nodes identification was relevant for only 2/274 patients (0.8%). Three patients (0.3%) had an allergic reaction with PBD, and anaphylactic shock occurred in two cases (0.2%). The added-value of PBD to reduce the false-negative rate of SLN mapping is only limited to the rare cases in which no radioactivity is detectable in the axilla (<1%). When a radioisotope mapping agent is available, the use of PBD should be avoided, because it can induce anaphylaxis. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Validation of the sentinel lymph node biopsy technique in head and neck cancers of the oral cavity.

PubMed

Radkani, Pejman; Mesko, Thomas W; Paramo, Juan C

2013-12-01

The purpose of this study was to present our experience and validate the use of sentinel lymph node (SLN) mapping in patients with head and neck cancers. A retrospective review of a prospectively collected database of patients with a diagnosis of squamous cell carcinomas of the head and neck from 2008 to 2011 was done. The group consisted of a total of 20 patients. The first node(s) highlighted with blue, or identified as radioactive by Tc99-sulfur radioactive colloid, was (were) identified as the SLNs. In the first seven patients, formal modified neck dissection was performed. In the remaining 13 patients, only a SLN biopsy procedure was done. At least one SLN was identified in all 20 patients (100%). Only one patient (5%) had positive nodes. In this case, the SLN was also positive. In the remaining 19 cases, all lymph nodes were negative. After an average of 24 months of follow-up, there have been three local recurrences (15%) but no evidence of distant metastatic disease. SLN mapping in head and neck cancers is a feasible technique with a high identification rate and a low false-negative rate. Although the detection rate of regional metastatic disease compares favorably with published data as well as the disease-free and overall survival, further studies are warranted before considering this technique to be the "gold standard" in patients with oral squamous cell carcinoma and a negative neck by clinical examination and imaging studies.

DETERMINING THE PHARMACOKINETICS AND LONG-TERM BIODISTRIBUTION OF SiO2 NANOPARTICLES IN VIVO USING ACCELERATOR MASS SPECTROMETRY

PubMed Central

Malfatti, Michael A.; Palko, Heather A.; Kuhn, Edward A.; Turteltaub, Kenneth W.

2012-01-01

Biodistribution is an important factor in better understanding silica dioxide nanoparticle (SiNP) safety. Currently, comprehensive studies on biodistribution are lacking, most likely due to the lack of suitable analytical methods. Accelerator mass spectrometry (AMS) was used to investigate the relationship between administered dose, PK, and long-term biodistribution of 14C-SiNPs in vivo. PK analysis showed that SiNPs were rapidly cleared from the central compartment, were distributed to tissues of the reticuloendothelial system, and persisted in the tissue over the 8-week time course, raising questions about the potential for bioaccumulation and associated long-term effects. PMID:23075393

A Systematic Software, Firmware, and Hardware Codesign Methodology for Digital Signal Processing

DTIC Science & Technology

2014-03-01

possible mappings ...................................................60 Table 25. Possible optimal leaf -nodes... size weight and power UAV unmanned aerial vehicle UHF ultra-high frequency UML universal modeling language Verilog verify logic VHDL VHSIC...optimal leaf -nodes to some design patterns for embedded system design. Software and hardware partitioning is a very difficult challenge in the field of

Sentinel lymph node detection rates using indocyanine green in women with early-stage cervical cancer.

PubMed

Beavis, Anna L; Salazar-Marioni, Sergio; Sinno, Abdulrahman K; Stone, Rebecca L; Fader, Amanda N; Santillan-Gomez, Antonio; Tanner, Edward J

2016-11-01

Our study objective was to determine feasibility and mapping rates using indocyanine green (ICG) for sentinel lymph node (SLN) mapping in early-stage cervical cancer. We performed a retrospective review of all women who underwent SLN mapping with ICG during primary surgical management of early-stage cervical cancer by robotic-assisted radical hysterectomy (RA-RH) or fertility-sparing surgery. Patients were treated at two high-volume centers from 10/2012 to 02/2016. Completion pelvic lymphadenectomy was performed after SLN biopsy; additionally, removal of clinically enlarged/suspicious nodes was part of the SLN treatment algorithm. Thirty women with a median age of 42.5 and BMI of 26.5 were included. Most (90%) had stage IB disease, and 67% had squamous histology. RA-RH was performed in 86.7% of cases. One patient underwent fertility-sparing surgery. Median cervical tumor size was 2.0cm. At least one SLN was detected in all cases (100%), with bilateral mapping achieved in 87%. SLN detection was not impacted by tumor size and was most commonly identified in the hypogastric (40.3%), obturator (26.0%), and external iliac (20.8%) regions. Five cases of lymphatic metastasis were identified (16.7%): three in clinically enlarged SLNs, one in a clinically enlarged non-SLN, and one case with cytokeratin positive cells in an SLN. All metastatic disease would have been detected even if full lymphadenectomy had been omitted from our treatment algorithm, CONCLUSIONS: SLN mapping with ICG is feasible and results in high detection rates in women with early-stage cervical cancer. Prospective studies are needed to determine if SLN mapping can replace lymphadenectomy in this setting. Copyright © 2016 Elsevier Inc. All rights reserved.

An Isometric Mapping Based Co-Location Decision Tree Algorithm

NASA Astrophysics Data System (ADS)

Zhou, G.; Wei, J.; Zhou, X.; Zhang, R.; Huang, W.; Sha, H.; Chen, J.

2018-05-01

Decision tree (DT) induction has been widely used in different pattern classification. However, most traditional DTs have the disadvantage that they consider only non-spatial attributes (ie, spectral information) as a result of classifying pixels, which can result in objects being misclassified. Therefore, some researchers have proposed a co-location decision tree (Cl-DT) method, which combines co-location and decision tree to solve the above the above-mentioned traditional decision tree problems. Cl-DT overcomes the shortcomings of the existing DT algorithms, which create a node for each value of a given attribute, which has a higher accuracy than the existing decision tree approach. However, for non-linearly distributed data instances, the euclidean distance between instances does not reflect the true positional relationship between them. In order to overcome these shortcomings, this paper proposes an isometric mapping method based on Cl-DT (called, (Isomap-based Cl-DT), which is a method that combines heterogeneous and Cl-DT together. Because isometric mapping methods use geodetic distances instead of Euclidean distances between non-linearly distributed instances, the true distance between instances can be reflected. The experimental results and several comparative analyzes show that: (1) The extraction method of exposed carbonate rocks is of high accuracy. (2) The proposed method has many advantages, because the total number of nodes, the number of leaf nodes and the number of nodes are greatly reduced compared to Cl-DT. Therefore, the Isomap -based Cl-DT algorithm can construct a more accurate and faster decision tree.

SU-F-J-100: Standardized Biodistribution Template for Nuclear Medicine Dosimetry Collection and Reporting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kesner, A; Poli, G; Beykan, S

Purpose: As the field of Nuclear Medicine moves forward with efforts to integrate radiation dosimetry into clinical practice we can identify the challenge posed by the lack of standardized dose calculation methods and protocols. All personalized internal dosimetry is derived by projecting biodistribution measurements into dosimetry calculations. In an effort to standardize organization of data and its reporting, we have developed, as a sequel to the EANM recommendation of “Good Dosimetry Reporting”, a freely available biodistribution template, which can be used to create a common point of reference for dosimetry data. It can be disseminated, interpreted, and used for methodmore » development widely across the field. Methods: A generalized biodistribution template was built in a comma delineated format (.csv) to be completed by users performing biodistribution measurements. The template is available for free download. The download site includes instructions and other usage details on the template. Results: This is a new resource developed for the community. It is our hope that users will consider integrating it into their dosimetry operations. Having biodistribution data available and easily accessible for all patients processed is a strategy for organizing large amounts of information. It may enable users to create their own databases that can be analyzed for multiple aspects of dosimetry operations. Furthermore, it enables population data to easily be reprocessed using different dosimetry methodologies. With respect to dosimetry-related research and publications, the biodistribution template can be included as supplementary material, and will allow others in the community to better compare calculations and results achieved. Conclusion: As dosimetry in nuclear medicine become more routinely applied in clinical applications, we, as a field, need to develop the infrastructure for handling large amounts of data. Our organ level biodistribution template can be used as a standard format for data collection, organization, as well as for dosimetry research and software development.« less

Using a local low rank plus sparse reconstruction to accelerate dynamic hyperpolarized 13C imaging using the bSSFP sequence

NASA Astrophysics Data System (ADS)

Milshteyn, Eugene; von Morze, Cornelius; Reed, Galen D.; Shang, Hong; Shin, Peter J.; Larson, Peder E. Z.; Vigneron, Daniel B.

2018-05-01

Acceleration of dynamic 2D (T2 Mapping) and 3D hyperpolarized 13C MRI acquisitions using the balanced steady-state free precession sequence was achieved with a specialized reconstruction method, based on the combination of low rank plus sparse and local low rank reconstructions. Methods were validated using both retrospectively and prospectively undersampled in vivo data from normal rats and tumor-bearing mice. Four-fold acceleration of 1-2 mm isotropic 3D dynamic acquisitions with 2-5 s temporal resolution and two-fold acceleration of 0.25-1 mm2 2D dynamic acquisitions was achieved. This enabled visualization of the biodistribution of [2-13C]pyruvate, [1-13C]lactate, [13C, 15N2]urea, and HP001 within heart, kidneys, vasculature, and tumor, as well as calculation of high resolution T2 maps.

Clinical significance of the anterosuperior lymph nodes along the common hepatic artery identified by sentinel node mapping in patients with gastric cancer.

PubMed

Shimada, Ayako; Takeuchi, Hiroya; Kamiya, Satoshi; Fukuda, Kazumasa; Nakamura, Rieko; Takahashi, Tsunehiro; Wada, Norihito; Kawakubo, Hirofumi; Saikawa, Yoshiro; Omori, Tai; Nakahara, Tadaki; Jinzaki, Masahiro; Murakami, Koji; Kitagawa, Yuko

2016-10-01

The sentinel node (SN) concept is safely applied and validated in early gastric cancer. Gastric lymph nodes are divided into five basins with the main gastric arteries, and the anterosuperior lymph nodes with the common hepatic artery (No. 8a) are classified in the right gastric artery (r-GA) basin. Although No. 8a are considered to have lymphatic flow from the r-GA basin, there might be additional multiple lymphatic flows into No. 8a. The aim of this study is to analyze the lymphatic flows to No. 8a and to investigate the clinical significance of No. 8a as a sentinel node (SN No. 8a). Four hundred and twenty-nine patients with cT1N0 or cT2N0 gastric cancer underwent SN mapping. We used technetium-99 tin colloid solution and blue dye as a tracer. We detected SN No. 8a in 35 (8.2 %) patients. In these patients, we detected SN No. 8a with SNs that belonged to the left gastric artery (l-GA) basin (66 %), right gastroepiploic artery (r-GEA) basin (54 %), and right gastric artery (r-GA) basin (46 %). In addition, celiac artery lymph nodes were detected as SNs significantly more frequently. Function-preserving surgery was performed significantly less often in patients with SN No. 8a (p =0.018). We found that SN No. 8a seemed to have lymphatic flow not only from the r-GA basin, but also from the l-GA basin or r-GEA basin. When SN No. 8a are detected, we should be careful to perform function-preserving surgery, even in SN-negative cases.

Luminescent probes for optical in vivo imaging

NASA Astrophysics Data System (ADS)

Texier, Isabelle; Josserand, Veronique; Garanger, Elisabeth; Razkin, Jesus; Jin, Zhaohui; Dumy, Pascal; Favrot, Marie; Boturyn, Didier; Coll, Jean-Luc

2005-04-01

Going along with instrumental development for small animal fluorescence in vivo imaging, we are developing molecular fluorescent probes, especially for tumor targeting. Several criteria have to be taken into account for the optimization of the luminescent label. It should be adapted to the in vivo imaging optical conditions : red-shifted absorption and emission, limited overlap between absorption and emission for a good signal filtering, optimized luminescence quantum yield, limited photo-bleaching. Moreover, the whole probe should fulfill the biological requirements for in vivo labeling : adapted blood-time circulation, biological conditions compatibility, low toxicity. We here demonstrate the ability of the imaging fluorescence set-up developed in LETI to image the bio-distribution of molecular probes on short times after injection. Targeting with Cy5 labeled holo-transferrin of subcutaneous TS/Apc (angiogenic murine breast carcinoma model) or IGROV1 (human ovarian cancer) tumors was achieved. Differences in the kinetics of the protein uptake by the tumors were evidenced. IGROV1 internal metastatic nodes implanted in the peritoneal cavity could be detected in nude mice. However, targeted metastatic nodes in lung cancer could only be imaged after dissection of the mouse. These results validate our fluorescence imaging set-up and the use of Cy5 as a luminescent label. New fluorescent probes based on this dye and a molecular delivery template (the RAFT molecule) can thus be envisioned.

Coarse-graining and self-dissimilarity of complex networks

NASA Astrophysics Data System (ADS)

Itzkovitz, Shalev; Levitt, Reuven; Kashtan, Nadav; Milo, Ron; Itzkovitz, Michael; Alon, Uri

2005-01-01

Can complex engineered and biological networks be coarse-grained into smaller and more understandable versions in which each node represents an entire pattern in the original network? To address this, we define coarse-graining units as connectivity patterns which can serve as the nodes of a coarse-grained network and present algorithms to detect them. We use this approach to systematically reverse-engineer electronic circuits, forming understandable high-level maps from incomprehensible transistor wiring: first, a coarse-grained version in which each node is a gate made of several transistors is established. Then the coarse-grained network is itself coarse-grained, resulting in a high-level blueprint in which each node is a circuit module made of many gates. We apply our approach also to a mammalian protein signal-transduction network, to find a simplified coarse-grained network with three main signaling channels that resemble multi-layered perceptrons made of cross-interacting MAP-kinase cascades. We find that both biological and electronic networks are “self-dissimilar,” with different network motifs at each level. The present approach may be used to simplify a variety of directed and nondirected, natural and designed networks.

Binocular Goggle Augmented Imaging and Navigation System provides real-time fluorescence image guidance for tumor resection and sentinel lymph node mapping

PubMed Central

B. Mondal, Suman; Gao, Shengkui; Zhu, Nan; Sudlow, Gail P.; Liang, Kexian; Som, Avik; Akers, Walter J.; Fields, Ryan C.; Margenthaler, Julie; Liang, Rongguang; Gruev, Viktor; Achilefu, Samuel

2015-01-01

The inability to identify microscopic tumors and assess surgical margins in real-time during oncologic surgery leads to incomplete tumor removal, increases the chances of tumor recurrence, and necessitates costly repeat surgery. To overcome these challenges, we have developed a wearable goggle augmented imaging and navigation system (GAINS) that can provide accurate intraoperative visualization of tumors and sentinel lymph nodes in real-time without disrupting normal surgical workflow. GAINS projects both near-infrared fluorescence from tumors and the natural color images of tissue onto a head-mounted display without latency. Aided by tumor-targeted contrast agents, the system detected tumors in subcutaneous and metastatic mouse models with high accuracy (sensitivity = 100%, specificity = 98% ± 5% standard deviation). Human pilot studies in breast cancer and melanoma patients using a near-infrared dye show that the GAINS detected sentinel lymph nodes with 100% sensitivity. Clinical use of the GAINS to guide tumor resection and sentinel lymph node mapping promises to improve surgical outcomes, reduce rates of repeat surgery, and improve the accuracy of cancer staging. PMID:26179014

Using GIS databases for simulated nightlight imagery

NASA Astrophysics Data System (ADS)

Zollweg, Joshua D.; Gartley, Michael; Roskovensky, John; Mercier, Jeffery

2012-06-01

Proposed is a new technique for simulating nighttime scenes with realistically-modelled urban radiance. While nightlight imagery is commonly used to measure urban sprawl,1 it is uncommon to use urbanization as metric to develop synthetic nighttime scenes. In the developed methodology, the open-source Open Street Map (OSM) Geographic Information System (GIS) database is used. The database is comprised of many nodes, which are used to dene the position of dierent types of streets, buildings, and other features. These nodes are the driver used to model urban nightlights, given several assumptions. The rst assumption is that the spatial distribution of nodes is closely related to the spatial distribution of nightlights. Work by Roychowdhury et al has demonstrated the relationship between urban lights and development. 2 So, the real assumption being made is that the density of nodes corresponds to development, which is reasonable. Secondly, the local density of nodes must relate directly to the upwelled radiance within the given locality. Testing these assumptions using Albuquerque and Indianapolis as example cities revealed that dierent types of nodes produce more realistic results than others. Residential street nodes oered the best performance for any single node type, among the types tested in this investigation. Other node types, however, still provide useful supplementary data. Using streets and buildings dened in the OSM database allowed automated generation of simulated nighttime scenes of Albuquerque and Indianapolis in the Digital Imaging and Remote Sensing Image Generation (DIRSIG) model. The simulation was compared to real data from the recently deployed National Polar-orbiting Operational Environmental Satellite System(NPOESS) Visible Infrared Imager Radiometer Suite (VIIRS) platform. As a result of the comparison, correction functions were used to correct for discrepancies between simulated and observed radiance. Future work will include investigating more advanced approaches for mapping the spatial extent of nightlights, based on the distribution of dierent node types in local neighbourhoods. This will allow the spectral prole of each region to be dynamically adjusted, in addition to simply modifying the magnitude of a single source type.

Slow CCL2-dependent translocation of biopersistent particles from muscle to brain

PubMed Central

2013-01-01

Background Long-term biodistribution of nanomaterials used in medicine is largely unknown. This is the case for alum, the most widely used vaccine adjuvant, which is a nanocrystalline compound spontaneously forming micron/submicron-sized agglomerates. Although generally well tolerated, alum is occasionally detected within monocyte-lineage cells long after immunization in presumably susceptible individuals with systemic/neurologic manifestations or autoimmune (inflammatory) syndrome induced by adjuvants (ASIA). Methods On the grounds of preliminary investigations in 252 patients with alum-associated ASIA showing both a selective increase of circulating CCL2, the major monocyte chemoattractant, and a variation in the CCL2 gene, we designed mouse experiments to assess biodistribution of vaccine-derived aluminum and of alum-particle fluorescent surrogates injected in muscle. Aluminum was detected in tissues by Morin stain and particle induced X-ray emission) (PIXE) Both 500 nm fluorescent latex beads and vaccine alum agglomerates-sized nanohybrids (Al-Rho) were used. Results Intramuscular injection of alum-containing vaccine was associated with the appearance of aluminum deposits in distant organs, such as spleen and brain where they were still detected one year after injection. Both fluorescent materials injected into muscle translocated to draining lymph nodes (DLNs) and thereafter were detected associated with phagocytes in blood and spleen. Particles linearly accumulated in the brain up to the six-month endpoint; they were first found in perivascular CD11b+ cells and then in microglia and other neural cells. DLN ablation dramatically reduced the biodistribution. Cerebral translocation was not observed after direct intravenous injection, but significantly increased in mice with chronically altered blood-brain-barrier. Loss/gain-of-function experiments consistently implicated CCL2 in systemic diffusion of Al-Rho particles captured by monocyte-lineage cells and in their subsequent neurodelivery. Stereotactic particle injection pointed out brain retention as a factor of progressive particle accumulation. Conclusion Nanomaterials can be transported by monocyte-lineage cells to DLNs, blood and spleen, and, similarly to HIV, may use CCL2-dependent mechanisms to penetrate the brain. This occurs at a very low rate in normal conditions explaining good overall tolerance of alum despite its strong neurotoxic potential. However, continuously escalating doses of this poorly biodegradable adjuvant in the population may become insidiously unsafe, especially in the case of overimmunization or immature/altered blood brain barrier or high constitutive CCL-2 production. PMID:23557144

Slow CCL2-dependent translocation of biopersistent particles from muscle to brain.

PubMed

Khan, Zakir; Combadière, Christophe; Authier, François-Jérôme; Itier, Valérie; Lux, François; Exley, Christopher; Mahrouf-Yorgov, Meriem; Decrouy, Xavier; Moretto, Philippe; Tillement, Olivier; Gherardi, Romain K; Cadusseau, Josette

2013-04-04

Long-term biodistribution of nanomaterials used in medicine is largely unknown. This is the case for alum, the most widely used vaccine adjuvant, which is a nanocrystalline compound spontaneously forming micron/submicron-sized agglomerates. Although generally well tolerated, alum is occasionally detected within monocyte-lineage cells long after immunization in presumably susceptible individuals with systemic/neurologic manifestations or autoimmune (inflammatory) syndrome induced by adjuvants (ASIA). On the grounds of preliminary investigations in 252 patients with alum-associated ASIA showing both a selective increase of circulating CCL2, the major monocyte chemoattractant, and a variation in the CCL2 gene, we designed mouse experiments to assess biodistribution of vaccine-derived aluminum and of alum-particle fluorescent surrogates injected in muscle. Aluminum was detected in tissues by Morin stain and particle induced X-ray emission) (PIXE) Both 500 nm fluorescent latex beads and vaccine alum agglomerates-sized nanohybrids (Al-Rho) were used. Intramuscular injection of alum-containing vaccine was associated with the appearance of aluminum deposits in distant organs, such as spleen and brain where they were still detected one year after injection. Both fluorescent materials injected into muscle translocated to draining lymph nodes (DLNs) and thereafter were detected associated with phagocytes in blood and spleen. Particles linearly accumulated in the brain up to the six-month endpoint; they were first found in perivascular CD11b+ cells and then in microglia and other neural cells. DLN ablation dramatically reduced the biodistribution. Cerebral translocation was not observed after direct intravenous injection, but significantly increased in mice with chronically altered blood-brain-barrier. Loss/gain-of-function experiments consistently implicated CCL2 in systemic diffusion of Al-Rho particles captured by monocyte-lineage cells and in their subsequent neurodelivery. Stereotactic particle injection pointed out brain retention as a factor of progressive particle accumulation. Nanomaterials can be transported by monocyte-lineage cells to DLNs, blood and spleen, and, similarly to HIV, may use CCL2-dependent mechanisms to penetrate the brain. This occurs at a very low rate in normal conditions explaining good overall tolerance of alum despite its strong neurotoxic potential. However, continuously escalating doses of this poorly biodegradable adjuvant in the population may become insidiously unsafe, especially in the case of overimmunization or immature/altered blood brain barrier or high constitutive CCL-2 production.

Visualizing weighted networks: a performance comparison of adjacency matrices versus node-link diagrams

NASA Astrophysics Data System (ADS)

McIntire, John P.; Osesina, O. Isaac; Bartley, Cecilia; Tudoreanu, M. Eduard; Havig, Paul R.; Geiselman, Eric E.

2012-06-01

Ensuring the proper and effective ways to visualize network data is important for many areas of academia, applied sciences, the military, and the public. Fields such as social network analysis, genetics, biochemistry, intelligence, cybersecurity, neural network modeling, transit systems, communications, etc. often deal with large, complex network datasets that can be difficult to interact with, study, and use. There have been surprisingly few human factors performance studies on the relative effectiveness of different graph drawings or network diagram techniques to convey information to a viewer. This is particularly true for weighted networks which include the strength of connections between nodes, not just information about which nodes are linked to other nodes. We describe a human factors study in which participants performed four separate network analysis tasks (finding a direct link between given nodes, finding an interconnected node between given nodes, estimating link strengths, and estimating the most densely interconnected nodes) on two different network visualizations: an adjacency matrix with a heat-map versus a node-link diagram. The results should help shed light on effective methods of visualizing network data for some representative analysis tasks, with the ultimate goal of improving usability and performance for viewers of network data displays.

A critical review of variables affecting the accuracy and false-negative rate of sentinel node biopsy procedures in early breast cancer.

PubMed

Vijayakumar, Vani; Boerner, Philip S; Jani, Ashesh B; Vijayakumar, Srinivasan

2005-05-01

Radionuclide sentinel lymph node localization and biopsy is a staging procedure that is being increasingly used to evaluate patients with invasive breast cancer who have clinically normal axillary nodes. The most important prognostic indicator in patients with invasive breast cancer is the axillary node status, which must also be known for correct staging, and influences the selection of adjuvant therapies. The accuracy of sentinel lymph node localization depends on a number of factors, including the injection method, the operating surgeon's experience and the hospital setting. The efficacy of sentinel lymph node mapping can be determined by two measures: the sentinel lymph node identification rate and the false-negative rate. Of these, the false-negative rate is the most important, based on a review of 92 studies. As sentinel lymph node procedures vary widely, nuclear medicine physicians and radiologists must be acquainted with the advantages and disadvantages of the various techniques. In this review, the factors that influence the success of different techniques are examined, and studies which have investigated false-negative rates and/or sentinel lymph node identification rates are summarized.

Mapping higher-order relations between brain structure and function with embedded vector representations of connectomes.

PubMed

Rosenthal, Gideon; Váša, František; Griffa, Alessandra; Hagmann, Patric; Amico, Enrico; Goñi, Joaquín; Avidan, Galia; Sporns, Olaf

2018-06-05

Connectomics generates comprehensive maps of brain networks, represented as nodes and their pairwise connections. The functional roles of nodes are defined by their direct and indirect connectivity with the rest of the network. However, the network context is not directly accessible at the level of individual nodes. Similar problems in language processing have been addressed with algorithms such as word2vec that create embeddings of words and their relations in a meaningful low-dimensional vector space. Here we apply this approach to create embedded vector representations of brain networks or connectome embeddings (CE). CE can characterize correspondence relations among brain regions, and can be used to infer links that are lacking from the original structural diffusion imaging, e.g., inter-hemispheric homotopic connections. Moreover, we construct predictive deep models of functional and structural connectivity, and simulate network-wide lesion effects using the face processing system as our application domain. We suggest that CE offers a novel approach to revealing relations between connectome structure and function.

Sentinel node mapping for gastric cancer: a prospective multicenter trial in Japan.

PubMed

Kitagawa, Yuko; Takeuchi, Hiroya; Takagi, Yu; Natsugoe, Shoji; Terashima, Masanori; Murakami, Nozomu; Fujimura, Takashi; Tsujimoto, Hironori; Hayashi, Hideki; Yoshimizu, Nobunari; Takagane, Akinori; Mohri, Yasuhiko; Nabeshima, Kazuhito; Uenosono, Yoshikazu; Kinami, Shinichi; Sakamoto, Junichi; Morita, Satoshi; Aikou, Takashi; Miwa, Koichi; Kitajima, Masaki

2013-10-10

Complicated gastric lymphatic drainage potentially undermines the utility of sentinel node (SN) biopsy in patients with gastric cancer. Encouraged by several favorable single-institution reports, we conducted a multicenter, single-arm, phase II study of SN mapping that used a standardized dual tracer endoscopic injection technique. Patients with previously untreated cT1 or cT2 gastric adenocarcinomas < 4 cm in gross diameter were eligible for inclusion in this study. SN mapping was performed by using a standardized dual tracer endoscopic injection technique. Following biopsy of the identified SNs, mandatory comprehensive D2 or modified D2 gastrectomy was performed according to current Japanese Gastric Cancer Association guidelines. Among 433 patients who gave preoperative consent, 397 were deemed eligible on the basis of surgical findings. SN biopsy was performed in all patients, and the SN detection rate was 97.5% (387 of 397). Of 57 patients with lymph node metastasis by conventional hematoxylin and eosin staining, 93% (53 of 57) had positive SNs, and the accuracy of nodal evaluation for metastasis was 99% (383 of 387). Only four false-negative SN biopsies were observed, and pathologic analysis revealed that three of those biopsies were pT2 or tumors > 4 cm. We observed no serious adverse effects related to endoscopic tracer injection or the SN mapping procedure. The endoscopic dual tracer method for SN biopsy was confirmed as safe and effective when applied to the superficial, relatively small gastric adenocarcinomas included in this study.

Practice patterns of lymph-node mapping and sentinel-node biopsy for breast cancer in British Columbia.

PubMed

Chua, Boon; Olivotto, Ivo A; Donald, James C; Hayashi, Allen H; Davis, Noelle; Rusnak, Conrad H

2003-08-01

Because there is no standardized technique for mapping of lymph nodes and no optimal technique for evaluating the sentinel node, we decided to evaluate practice patterns for sentinel-node biopsy (SNB) for breast cancer in British Columbia 5 years after its introduction in 1996. We carried out mail and telephone surveys of general surgeons performing at least 1 SNB (n = 28) or not performing SNB (n = 50), and carried out telephone surveys or on-site visits with pathologists (n = 7) and nuclear medicine physicians (n = 5) from institutions supporting SNB in the province. We collected data on training, perceived indications and techniques for the surgical, imaging and pathologic assessments of SNB to obtain data on practice patterns in 2001 and the degree of consistency among surgeons and institutions involved in performing SNB and reasons for not adopting the SNB technique. By 2001, SNB was incorporated into the practice of 19% of surgeons (28 of 150) performing breast cancer surgery in British Columbia. The survey response rate among SNB surgeons was 89% (25 of 28). Twelve (48%) of the 25 surgeons implemented SNB in the context of a validation study. Ten (40%) of the 25 had no data management support to monitor their results. Surgical training included intraoperative mentoring alone (48%), formal training courses alone (20%), both (24%) and self-teaching (8%). One-third of the surgeons had performed fewer than 10 procedures. Five surgeons had abandoned routine axillary dissection. There was considerable variation regarding the indications for SNB, definition of a sentinel node and surgical techniques. All nuclear medicine departments had a written lymphatic mapping protocol, but each used a different volume and activity of radiotracer. Immunohistochemical evaluation of the sentinel nodes was performed at just 3 pathology laboratories. The survey response rate from surgeons not practising SNB was 54% (27 of 50). Among 24 responders in active practice, 7 (29%) planned to perform SNB; 79% had not decided on the SNB indications. Lack of operating room time was a major limiting factor. There was considerable variation in the surgical, nuclear medicine and pathology techniques for SNB in the absence of a planned approach for its implementation in British Columbia. Developing consensus around written guidelines for the indications and techniques of SNB may reduce this variation.

Photo-guided sentinel node mapping in breast cancer using marker-free photo-gamma fusion lymphoscintigraphy.

PubMed

Lee, Eun Seong; Chun, In Kook; Ha, Seunggyun; Yoon, Hai-Jeon; Jung, So-Youn; Lee, Seeyoun; Kim, Seok Won; Lee, Eun Sook; Kim, Taeyoon; Kim, Kwang Gi; Lee, Byung Il; Kim, Tae Sung; Kim, Seok-Ki

2013-03-01

Photo-gamma fusion lymphoscintigraphy (PGFLS) was developed by overlying a conventional planar gamma image on a photograph for the guidance of sentinel node biopsy. The feasibility and accuracy of PGFLS was assessed in breast cancer patients. A digital camera and a gamma camera were coordinated to obtain photograph and gamma images from the same angle. Using the distance to the object and calibration acquisition with a flat phantom and radioactive markers, PGFLS was performed both in phantom and in patients without fiducial markers. Marker-free PGFLS was verified using flat phantom, anthropomorphic phantom with markers simulating sentinel nodes and breast cancer patients. In addition, the depth of the radioactive marker or sentinel node was calculated using two gamma images taken at right angles. The feasibility and accuracy of PGFLS were assessed in terms of mismatch errors of co-registration and depth with reference to the data from SPECT/CT. The mismatch error was less than 6 mm in the flat phantom image at a distance from 50 to 62 cm without misalignment. In the anthropomorphic phantom study, co-registration error was 0.42 ± 0.29 cm; depth error was 0.51 ± 0.37 cm, which was well correlated with the reference value on SPECT/CT (x scale: R(2) = 0.99, p < 0.01; y scale: R(2) = 0.99, p < 0.01; depth: R(2) = 0.99, p < 0.01). In ten patients with breast cancer referred for lympho-SPECT/CT, PGFSL enabled photo-guided sentinel lymph node mapping with acceptable accuracy (co-registration error, 0.47 ± 0.24 cm; depth error, 1.20 ±0.41 cm). The results from PGFSL showed close correlation with those from SPECT/CT (x scale: R(2) = 0.99, p < 0.01; y scale: R(2) = 0.98, p < 0.01; depth: R(2) = 0.77, p < 0.01). The novel and convenient PGFLS technique is clinically feasible, showing acceptable accuracy and providing additional visual and quantitative information for sentinel lymph node mapping. This approach will facilitate photo-guided sentinel lymph node dissection in breast cancer.

Cloud GPU-based simulations for SQUAREMR.

PubMed

Kantasis, George; Xanthis, Christos G; Haris, Kostas; Heiberg, Einar; Aletras, Anthony H

2017-01-01

Quantitative Magnetic Resonance Imaging (MRI) is a research tool, used more and more in clinical practice, as it provides objective information with respect to the tissues being imaged. Pixel-wise T 1 quantification (T 1 mapping) of the myocardium is one such application with diagnostic significance. A number of mapping sequences have been developed for myocardial T 1 mapping with a wide range in terms of measurement accuracy and precision. Furthermore, measurement results obtained with these pulse sequences are affected by errors introduced by the particular acquisition parameters used. SQUAREMR is a new method which has the potential of improving the accuracy of these mapping sequences through the use of massively parallel simulations on Graphical Processing Units (GPUs) by taking into account different acquisition parameter sets. This method has been shown to be effective in myocardial T 1 mapping; however, execution times may exceed 30min which is prohibitively long for clinical applications. The purpose of this study was to accelerate the construction of SQUAREMR's multi-parametric database to more clinically acceptable levels. The aim of this study was to develop a cloud-based cluster in order to distribute the computational load to several GPU-enabled nodes and accelerate SQUAREMR. This would accommodate high demands for computational resources without the need for major upfront equipment investment. Moreover, the parameter space explored by the simulations was optimized in order to reduce the computational load without compromising the T 1 estimates compared to a non-optimized parameter space approach. A cloud-based cluster with 16 nodes resulted in a speedup of up to 13.5 times compared to a single-node execution. Finally, the optimized parameter set approach allowed for an execution time of 28s using the 16-node cluster, without compromising the T 1 estimates by more than 10ms. The developed cloud-based cluster and optimization of the parameter set reduced the execution time of the simulations involved in constructing the SQUAREMR multi-parametric database thus bringing SQUAREMR's applicability within time frames that would be likely acceptable in the clinic. Copyright © 2016 Elsevier Inc. All rights reserved.

PET/CT with 18F-choline: Physiological whole bio-distribution in male and female subjects and diagnostic pitfalls on 1000 prostate cancer patients: 18F-choline PET/CT bio-distribution and pitfalls. A southern Italian experience.

PubMed

Calabria, Ferdinando; Chiaravalloti, Agostino; Cicciò, Carmelo; Gangemi, Vincenzo; Gullà, Domenico; Rocca, Federico; Gallo, Gianpasquale; Cascini, Giuseppe Lucio; Schillaci, Orazio

2017-08-01

The 11 C/ 18 F-choline is a PET/CT radiopharmaceutical useful in detecting tumors with high lipogenesis. 11 C/ 18 F-choline uptake can occur in physiological conditions or tumors. The knowledge of its bio-distribution is essential to recognize physiologic variants or diagnostic pitfalls. Moreover, few information are available on the bio-distribution of this tracer in female patients. Our aim was to discuss some documented 18 F-choline PET/CT pitfalls in prostate cancer patients. Our secondary aim was to describe the 18 F-choline bio-distribution in the female body. We collected diagnostic pitfalls in three PET centers examining 1000 prostate cancer by 18 F-choline PET/CT. All pitfalls were ensured by follow-up, imaging and/or histology. We also performed whole body 18 F-choline PET/CT in 5 female patients. 169/1000 (16.9%) patients showed pitfalls not owing to prostate cancer. These findings were due to inflammation, benign tumors while, in 1% of examined patients, a concomitant neoplasm was found. In the female body, the breast showed low physiological uptake. The accurate knowledge of 18 F-choline PET/CT bio-distribution and diagnostic pitfalls is essential. Correlative imaging and histological exam are often necessary to depict pitfalls. In women, the uptake in the breast is due to the physiological gradient of 18 F-choline uptake in the exocrine glands. Our results confirm the possibility of 18 F-choline uptake in several diseases other than prostate cancer. However, our experience was acquired on a large population and shows that a conspicuous amount of 18 F-choline diagnostic pitfalls are easily recognizable and attributable to inflammation. A new advance in knowledge is the minimal difference in terms of physiological tracer bio-distribution between male and female patients. The knowledge of the physiological bio-distribution and of the potential pitfalls linked of a tracer could help physicians to choose the best diagnostic and therapeutic approaches for a better patient quality of life. Copyright © 2017 Elsevier Inc. All rights reserved.

A Hierarchical and Distributed Approach for Mapping Large Applications to Heterogeneous Grids using Genetic Algorithms

NASA Technical Reports Server (NTRS)

Sanyal, Soumya; Jain, Amit; Das, Sajal K.; Biswas, Rupak

2003-01-01

In this paper, we propose a distributed approach for mapping a single large application to a heterogeneous grid environment. To minimize the execution time of the parallel application, we distribute the mapping overhead to the available nodes of the grid. This approach not only provides a fast mapping of tasks to resources but is also scalable. We adopt a hierarchical grid model and accomplish the job of mapping tasks to this topology using a scheduler tree. Results show that our three-phase algorithm provides high quality mappings, and is fast and scalable.

Localization in Self-Healing Autonomous Sensor Networks (SASNet): Studies on Cooperative Localization of Sensor Nodes using Distributed Maps

DTIC Science & Technology

2008-01-01

CCA-MAP algorithm are analyzed. Further, we discuss the design considerations of the discussed cooperative localization algorithms to compare and...MAP and CCA-MAP to compare and evaluate their performance. Then a preliminary design analysis is given to address the implementation requirements and...plus précis, avec un nombre inférieur de nœuds ancres, comparativement aux autres types de schémas de localisation. En réalité, les algorithmes de

How Art Works: The National Endowment for the Arts' Five-Year Research Agenda, with a System Map and Measurement Model. Appendix A & B

ERIC Educational Resources Information Center

National Endowment for the Arts, 2012

2012-01-01

This paper presents two appendices supporting the "How Art Works: The National Endowment for the Arts' Five-Year Research Agenda, with a System Map and Measurement Model" report. In Appendix A, brief descriptions of relevant studies and datasets for each node in the "How Art Works" system map are presented. This appendix is meant to supply…

Sentinel lymph node mapping in endometrial cancer: comparison of fluorescence dye with traditional radiocolloid and blue.

PubMed

Papadia, Andrea; Gasparri, Maria Luisa; Buda, Alessandro; Mueller, Michael D

2017-10-01

Sentinel lymph node (SLN) mapping in endometrial cancer (EMCA) is rapidly gaining acceptance in the clinical community. As compared to a full lymphadenectomy in every patient, to a selective lymphadenectomy after frozen section of uterus in selected patients with intrauterine risk factors or to a strategy in which a lymphadenectomy is always omitted, SLN mapping seems to be a reasonable and oncologically safe middle ground. Various protocols can be used when applying an SLN mapping. In this manuscript we review the characteristics, toxicity and clinical impact of technetium-99m radiocolloid (Tc-99m), of the blue dyes (methylene blue, isosulfan blue and patent blue) and of indocyanine green (ICG). ICG has an excellent toxicity profile, has higher overall and bilateral detection rates as compared to blue dyes and higher bilateral detection rates as compared to a combination of Tc-99m and blue dye. The detrimental effect of BMI on the detection rates is attenuated when ICG is used as a tracer. The ease of use of the ICG SLN mapping is perceived by the patients as a better quality of care delivered. Whenever possible, ICG should be favored over the other tracers for SLN mapping in EMCA patients.

An Intracranial Electroencephalography (iEEG) Brain Function Mapping Tool with an Application to Epilepsy Surgery Evaluation.

PubMed

Wang, Yinghua; Yan, Jiaqing; Wen, Jianbin; Yu, Tao; Li, Xiaoli

2016-01-01

Before epilepsy surgeries, intracranial electroencephalography (iEEG) is often employed in function mapping and epileptogenic foci localization. Although the implanted electrodes provide crucial information for epileptogenic zone resection, a convenient clinical tool for electrode position registration and Brain Function Mapping (BFM) visualization is still lacking. In this study, we developed a BFM Tool, which facilitates electrode position registration and BFM visualization, with an application to epilepsy surgeries. The BFM Tool mainly utilizes electrode location registration and function mapping based on pre-defined brain models from other software. In addition, the electrode node and mapping properties, such as the node size/color, edge color/thickness, mapping method, can be adjusted easily using the setting panel. Moreover, users may manually import/export location and connectivity data to generate figures for further application. The role of this software is demonstrated by a clinical study of language area localization. The BFM Tool helps clinical doctors and researchers visualize implanted electrodes and brain functions in an easy, quick and flexible manner. Our tool provides convenient electrode registration, easy brain function visualization, and has good performance. It is clinical-oriented and is easy to deploy and use. The BFM tool is suitable for epilepsy and other clinical iEEG applications.

An Intracranial Electroencephalography (iEEG) Brain Function Mapping Tool with an Application to Epilepsy Surgery Evaluation

PubMed Central

Wang, Yinghua; Yan, Jiaqing; Wen, Jianbin; Yu, Tao; Li, Xiaoli

2016-01-01

Objects: Before epilepsy surgeries, intracranial electroencephalography (iEEG) is often employed in function mapping and epileptogenic foci localization. Although the implanted electrodes provide crucial information for epileptogenic zone resection, a convenient clinical tool for electrode position registration and Brain Function Mapping (BFM) visualization is still lacking. In this study, we developed a BFM Tool, which facilitates electrode position registration and BFM visualization, with an application to epilepsy surgeries. Methods: The BFM Tool mainly utilizes electrode location registration and function mapping based on pre-defined brain models from other software. In addition, the electrode node and mapping properties, such as the node size/color, edge color/thickness, mapping method, can be adjusted easily using the setting panel. Moreover, users may manually import/export location and connectivity data to generate figures for further application. The role of this software is demonstrated by a clinical study of language area localization. Results: The BFM Tool helps clinical doctors and researchers visualize implanted electrodes and brain functions in an easy, quick and flexible manner. Conclusions: Our tool provides convenient electrode registration, easy brain function visualization, and has good performance. It is clinical-oriented and is easy to deploy and use. The BFM tool is suitable for epilepsy and other clinical iEEG applications. PMID:27199729

A Global Orientation Map in the Primary Visual Cortex (V1): Could a Self Organizing Model Reveal Its Hidden Bias?

PubMed Central

Philips, Ryan T.; Chakravarthy, V. Srinivasa

2017-01-01

A remarkable accomplishment of self organizing models is their ability to simulate the development of feature maps in the cortex. Additionally, these models have been trained to tease out the differential causes of multiple feature maps, mapped on to the same output space. Recently, a Laterally Interconnected Synergetically Self Organizing Map (LISSOM) model has been used to simulate the mapping of eccentricity and meridional angle onto orthogonal axes in the primary visual cortex (V1). This model is further probed to simulate the development of the radial bias in V1, using a training set that consists of both radial (rectangular bars of random size and orientation) as well as non-radial stimuli. The radial bias describes the preference of the visual system toward orientations that match the angular position (meridional angle) of that orientation with respect to the point of fixation. Recent fMRI results have shown that there exists a coarse scale orientation map in V1, which resembles the meridional angle map, thereby providing a plausible neural basis for the radial bias. The LISSOM model, trained for the development of the retinotopic map, on probing for orientation preference, exhibits a coarse scale orientation map, consistent with these experimental results, quantified using the circular cross correlation (rc). The rc between the orientation map developed on probing with a thin annular ring containing sinusoidal gratings with a spatial frequency of 0.5 cycles per degree (cpd) and the corresponding meridional map for the same annular ring, has a value of 0.8894. The results also suggest that the radial bias goes beyond the current understanding of a node to node correlation between the two maps. PMID:28111542

A Global Orientation Map in the Primary Visual Cortex (V1): Could a Self Organizing Model Reveal Its Hidden Bias?

PubMed

Philips, Ryan T; Chakravarthy, V Srinivasa

2016-01-01

A remarkable accomplishment of self organizing models is their ability to simulate the development of feature maps in the cortex. Additionally, these models have been trained to tease out the differential causes of multiple feature maps, mapped on to the same output space. Recently, a Laterally Interconnected Synergetically Self Organizing Map (LISSOM) model has been used to simulate the mapping of eccentricity and meridional angle onto orthogonal axes in the primary visual cortex (V1). This model is further probed to simulate the development of the radial bias in V1, using a training set that consists of both radial (rectangular bars of random size and orientation) as well as non-radial stimuli. The radial bias describes the preference of the visual system toward orientations that match the angular position (meridional angle) of that orientation with respect to the point of fixation. Recent fMRI results have shown that there exists a coarse scale orientation map in V1, which resembles the meridional angle map, thereby providing a plausible neural basis for the radial bias. The LISSOM model, trained for the development of the retinotopic map, on probing for orientation preference, exhibits a coarse scale orientation map, consistent with these experimental results, quantified using the circular cross correlation ( r c ). The r c between the orientation map developed on probing with a thin annular ring containing sinusoidal gratings with a spatial frequency of 0.5 cycles per degree (cpd) and the corresponding meridional map for the same annular ring, has a value of 0.8894. The results also suggest that the radial bias goes beyond the current understanding of a node to node correlation between the two maps.

Comparison of a sentinel lymph node mapping algorithm and comprehensive lymphadenectomy in the detection of stage IIIC endometrial carcinoma at higher risk for nodal disease.

PubMed

Ducie, Jennifer A; Eriksson, Ane Gerda Zahl; Ali, Narisha; McGree, Michaela E; Weaver, Amy L; Bogani, Giorgio; Cliby, William A; Dowdy, Sean C; Bakkum-Gamez, Jamie N; Soslow, Robert A; Keeney, Gary L; Abu-Rustum, Nadeem R; Mariani, Andrea; Leitao, Mario M

2017-12-01

To determine if a sentinel lymph node (SLN) mapping algorithm will detect metastatic nodal disease in patients with intermediate-/high-risk endometrial carcinoma. Patients were identified and surgically staged at two collaborating institutions. The historical cohort (2004-2008) at one institution included patients undergoing complete pelvic and paraaortic lymphadenectomy to the renal veins (LND cohort). At the second institution an SLN mapping algorithm, including pathologic ultra-staging, was performed (2006-2013) (SLN cohort). Intermediate-risk was defined as endometrioid histology (any grade), ≥50% myometrial invasion; high-risk as serous or clear cell histology (any myometrial invasion). Patients with gross peritoneal disease were excluded. Isolated tumor cells, micro-metastases, and macro-metastases were considered node-positive. We identified 210 patients in the LND cohort, 202 in the SLN cohort. Nodal assessment was performed for most patients. In the intermediate-risk group, stage IIIC disease was diagnosed in 30/107 (28.0%) (LND), 29/82 (35.4%) (SLN) (P=0.28). In the high-risk group, stage IIIC disease was diagnosed in 20/103 (19.4%) (LND), 26 (21.7%) (SLN) (P=0.68). Paraaortic lymph node (LN) assessment was performed significantly more often in intermediate-/high-risk groups in the LND cohort (P<0.001). In the intermediate-risk group, paraaortic LN metastases were detected in 20/96 (20.8%) (LND) vs. 3/28 (10.7%) (SLN) (P=0.23). In the high-risk group, paraaortic LN metastases were detected in 13/82 (15.9%) (LND) and 10/56 (17.9%) (SLN) (%, P=0.76). SLN mapping algorithm provides similar detection rates of stage IIIC endometrial cancer. The SLN algorithm does not compromise overall detection compared to standard LND. Copyright © 2017 Elsevier Inc. All rights reserved.

Sentinel Lymph Node Mapping for Grade 1 Endometrial Cancer: Is it the Answer to the Surgical Staging Dilemma?

PubMed Central

Abu-Rustum, Nadeem R.; Khoury-Collado, Fady; Pandit-Taskar, Neeta; Soslow, Robert A.; Dao, Fanny; Sonoda, Yukio; Levine, Douglas A.; Brown, Carol L.; Chi, Dennis S.; Barakat, Richard R.; Gemignani, Mary L.

2014-01-01

Objective To describe the accuracy of SLN mapping in patients with a preoperative diagnosis of grade 1 endometrial cancer. Methods A prospective, non-randomized study of women with a preoperative diagnosis of endometrial cancer and clinical stage I disease was conducted. A subset analysis of patients with a preoperative diagnosis of grade 1 endometrial endometrioid cancer was performed. All patients had preoperative lymphoscintigraphy with Tc99m on the day of or day before surgery followed by an intraoperative injection of 2cc of isosulfan or methylene blue dye deep into the cervix or both cervix and fundus. All patients underwent hysterectomy, bilateral salpingo-oophorectomy, and regional nodal dissection. Hot and/or blue nodes were labeled as SLNs and sent for histopathological analysis. Results Forty-two patients with a preoperative diagnosis of grade 1 endometrial carcinoma treated from 3/06–8/08 were identified. Twenty-five(60%) had laparoscopic surgery; 17(40%) were treated by laparotomy. Preoperative lymphoscintigraphy visualized SLNs in 30 patients(71%); intraoperative localization of the SLN was possible in 36(86%). A median of 3 SLNs(range, 1–14) and 14.5 non-SLNs(range, 4–55) were examined. In all, 4/36(11%) had positive SLNs—3 seen on H&E and 1 as cytokeratin-positive cells on IHC. All node-positive cases were picked up by the SLN; there were no false-negative cases. The sensitivity of the SLN procedure in the 36 patients who had an SLN identified was 100%. Conclusion Sentinel lymph node mapping using a cervical injection with combined Tc and blue dye is feasible and accurate in patients with grade 1 endometrial cancer and may be a reasonable option for this select group of patients. Regional lymphadenectomy remains the gold standard in many practices, particularly for the approximately 15% of cases with failed SLN mapping. PMID:19232699

Investigations on pharmacokinetics and biodistribution of polymeric and solid lipid nanoparticulate systems of atypical antipsychotic drug: effect of material used and surface modification.

PubMed

Joseph, Emil; Saha, Ranendra N

2017-04-01

The present study focuses on the effect of material used for the preparation of nanoparticulate (NP) systems and surface modification on the pharmacokinetics and biodistribution of atypical antipsychotic, olanzapine (OLN). NP carriers of OLN were prepared from two different materials such as polymer (polycaprolactone) and solid lipid (Glyceryl monostearate). These systems were further surface modified with surfactant, Polysorbate 80 and studied for pharmacokinetics-biodistribution in Wistar rats using in-house developed bioanalytical methods. The pharmacokinetics and biodistribution studies resulted in a modified and varied distribution of NP systems with higher area under curve (AUC) values along with prolonged residence time of OLN in the rat blood circulation. The distribution of OLN to the brain was significantly enhanced with surfactant surface-modified NP systems, followed by nonsurface-modified NP formulations as compared with pure OLN solution. Biodistribution study demonstrated a low uptake of obtained NP systems by kidney and heart, thereby decreasing the nephrotoxicity and adverse cardiovascular effects. By coating the NP with surfactant, uptake of macrophage was found to be reduced. Thus, our studies confirmed that the biodistribution OLN could be modified effectively by incorporating in NP drug delivery systems prepared from different materials and surface modifications. A judicious selection of materials used for the preparation of delivery carriers and surface modifications would help to design a most efficient drug delivery system with better therapeutic efficacy.

Applications of the MapReduce programming framework to clinical big data analysis: current landscape and future trends

PubMed Central

2014-01-01

The emergence of massive datasets in a clinical setting presents both challenges and opportunities in data storage and analysis. This so called “big data” challenges traditional analytic tools and will increasingly require novel solutions adapted from other fields. Advances in information and communication technology present the most viable solutions to big data analysis in terms of efficiency and scalability. It is vital those big data solutions are multithreaded and that data access approaches be precisely tailored to large volumes of semi-structured/unstructured data. The MapReduce programming framework uses two tasks common in functional programming: Map and Reduce. MapReduce is a new parallel processing framework and Hadoop is its open-source implementation on a single computing node or on clusters. Compared with existing parallel processing paradigms (e.g. grid computing and graphical processing unit (GPU)), MapReduce and Hadoop have two advantages: 1) fault-tolerant storage resulting in reliable data processing by replicating the computing tasks, and cloning the data chunks on different computing nodes across the computing cluster; 2) high-throughput data processing via a batch processing framework and the Hadoop distributed file system (HDFS). Data are stored in the HDFS and made available to the slave nodes for computation. In this paper, we review the existing applications of the MapReduce programming framework and its implementation platform Hadoop in clinical big data and related medical health informatics fields. The usage of MapReduce and Hadoop on a distributed system represents a significant advance in clinical big data processing and utilization, and opens up new opportunities in the emerging era of big data analytics. The objective of this paper is to summarize the state-of-the-art efforts in clinical big data analytics and highlight what might be needed to enhance the outcomes of clinical big data analytics tools. This paper is concluded by summarizing the potential usage of the MapReduce programming framework and Hadoop platform to process huge volumes of clinical data in medical health informatics related fields. PMID:25383096

Expression of SNCG, MAP2, SDF-1 and CXCR4 in gastric adenocarcinoma and their clinical significance

PubMed Central

Zheng, Shufang; Shi, Lifang; Zhang, Yi; He, Tao

2014-01-01

Objectives: The purpose of the study was to detect the expression of SNCG, MAP2, SDF-1 and CXCR4 in gastric adenocarcinoma, and to evaluate their roles in the carcinogenesis of gastric adenocarcinoma, development, invasion and metastasis as well as their clinical significance. Methods: The expression of SNCG, MAP2, SDF-1 and CXCR4 was detected by SP immunohistochemical method in 225 cases of gastric adenocarcinoma and 105 cases of nonneoplastic adjacent gastric tissue. The expression of SNCG, MAP2, SDF-1 and CXCR4 mRNA was also detected by RT-PCR method in 50 cases of gastric adenocarcinoma and 30 cases of nonneoplastic adjacent gastric tissue. Results: The expression of SNCG, MAP2, SDF-1 and CXCR4 in the gastric adenocarcinoma was remarkably higher than those in the nonneoplastic adjacent gastric tissue (P < 0.01); The positive expression of SNCG and MAP2 was correlated with the depth of tumor invasion and the metastasis of lymph nodes (P < 0.05), and that of SDF-1 and CXCR4 was correlated with the metastasis of lymph nodes (P < 0.05). Conclusions: SNCG, MAP2, SDF-1 and CXCR4 may play an important role in the carcinogenesis, progression, invasion and metastasis of gastric adenocarcinoma. However, it still needs more exploration whether they can serve as promising therapeutic targets of gastric adenocarcinoma. PMID:25400739

Retrospective validation of the laparoscopic ICG SLN mapping in patients with grade 3 endometrial cancer.

PubMed

Papadia, Andrea; Gasparri, Maria Luisa; Radan, Anda P; Stämpfli, Chantal A L; Rau, Tilman T; Mueller, Michael D

2018-04-24

To evaluate the sensitivity, negative predictive value (NPV) and false-negative (FN) rate of the near infrared (NIR) indocyanine green (ICG) sentinel lymph node (SLN) mapping in patients with poorly differentiated endometrial cancer who have undergone a full pelvic and para-aortic lymphadenectomy after SLN mapping. We performed a retrospective analysis of patients with endometrial cancer undergoing a laparoscopic NIR-ICG SLN mapping followed by a systematic pelvic and para-aortic lymphadenectomy. Inclusion criteria were a grade 3 endometrial cancer or a high-risk histology (papillary serous, clear cell carcinoma, carcinosarcoma, and neuroendocrine carcinoma) and a completion pelvic and para-aortic lymphadenectomy to the renal vessels after SLN mapping. Overall and bilateral detection rates, sensitivity, NPV, and FN rates were calculated. From December 2012 until January 2017, 42 patients fulfilled inclusion criteria. Overall and bilateral detection rates were 100 and 90.5%, respectively. Overall, 23.8% of the patients had lymph node metastases. In one patient, despite negative bilateral pelvic SLNs, a metastatic non-SLN-isolated para-aortic metastasis was detected. This NSLN was clinically suspicious and sent to frozen section analysis during the surgery. FN rate, sensitivity, and NPV were 10, 90, and 97.1%, respectively. For the SLN mapping algorithm, FN rate, sensitivity, and NPV were 0, 100, and 100%, respectively. Laparoscopic NIR-ICG SLN mapping in high-risk endometrial cancer patients has acceptable sensitivity, FN rate, and NPV.

Proposal for optimal placement platform of bikes using queueing networks.

PubMed

Mizuno, Shinya; Iwamoto, Shogo; Seki, Mutsumi; Yamaki, Naokazu

2016-01-01

In recent social experiments, rental motorbikes and rental bicycles have been arranged at nodes, and environments where users can ride these bikes have been improved. When people borrow bikes, they return them to nearby nodes. Some experiments have been conducted using the models of Hamachari of Yokohama, the Niigata Rental Cycle, and Bicing. However, from these experiments, the effectiveness of distributing bikes was unclear, and many models were discontinued midway. Thus, we need to consider whether these models are effectively designed to represent the distribution system. Therefore, we construct a model to arrange the nodes for distributing bikes using a queueing network. To adopt realistic values for our model, we use the Google Maps application program interface. Thus, we can easily obtain values of distance and transit time between nodes in various places in the world. Moreover, we apply the distribution of a population to a gravity model and we compute the effective transition probability for this queueing network. If the arrangement of the nodes and number of bikes at each node is known, we can precisely design the system. We illustrate our system using convenience stores as nodes and optimize the node configuration. As a result, we can optimize simultaneously the number of nodes, node places, and number of bikes for each node, and we can construct a base for a rental cycle business to use our system.

Spectral imaging as a potential tool for optical sentinel lymph node biopsies

NASA Astrophysics Data System (ADS)

O'Sullivan, Jack D.; Hoy, Paul R.; Rutt, Harvey N.

2011-07-01

Sentinel Lymph Node Biopsy (SLNB) is an increasingly standard procedure to help oncologists accurately stage cancers. It is performed as an alternative to full axillary lymph node dissection in breast cancer patients, reducing the risk of longterm health problems associated with lymph node removal. Intraoperative analysis is currently performed using touchprint cytology, which can introduce significant delay into the procedure. Spectral imaging is forming a multi-plane image where reflected intensities from a number of spectral bands are recorded at each pixel in the spatial plane. We investigate the possibility of using spectral imaging to assess sentinel lymph nodes of breast cancer patients with a view to eventually developing an optical technique that could significantly reduce the time required to perform this procedure. We investigate previously reported spectra of normal and metastatic tissue in the visible and near infrared region, using them as the basis of dummy spectral images. We analyse these images using the spectral angle map (SAM), a tool routinely used in other fields where spectral imaging is prevalent. We simulate random noise in these images in order to determine whether the SAM can discriminate between normal and metastatic pixels as the quality of the images deteriorates. We show that even in cases where noise levels are up to 20% of the maximum signal, the spectral angle map can distinguish healthy pixels from metastatic. We believe that this makes spectral imaging a good candidate for further study in the development of an optical SLNB.

In Vivo Cytometry of Antigen-Specific T Cells Using 19F MRI

PubMed Central

Srinivas, Mangala; Turner, Michael S.; Janjic, Jelena M.; Morel, Penelope A.; Laidlaw, David H.; Ahrens, Eric T.

2009-01-01

Noninvasive methods to image the trafficking of phenotypically defined immune cells are paramount as we attempt to understand adaptive immunity. A 19F MRI-based methodology for tracking and quantifying cells of a defined phenotype is presented. These methods were applied to a murine inflammation model using antigen-specific T cells. The T cells that were intracellularly labeled ex vivo with a perfluoropolyether (PFPE) nanoemulsion and cells were transferred to a host receiving a localized inoculation of antigen. Longitudinal 19F MRI over 21 days revealed a dynamic accumulation and clearance of T cells in the lymph node (LN) draining the antigen. The apparent T-cell numbers were calculated in the LN from the time-lapse 19F MRI data. The effect of in vivo T-cell division on the 19F MRI cell quantification accuracy was investigated using fluorescence assays. Overall, in vivo cytometry using PFPE labeling and 19F MRI is broadly applicable to studies of whole-body cell biodistribution. PMID:19585593

Development of a minimal saponin vaccine adjuvant based on QS-21

NASA Astrophysics Data System (ADS)

Fernández-Tejada, Alberto; Chea, Eric K.; George, Constantine; Pillarsetty, Nagavarakishore; Gardner, Jeffrey R.; Livingston, Philip O.; Ragupathi, Govind; Lewis, Jason S.; Tan, Derek S.; Gin, David Y.

2014-07-01

Adjuvants are materials added to vaccines to enhance the immunological response to an antigen. QS-21 is a natural product adjuvant under investigation in numerous vaccine clinical trials, but its use is constrained by scarcity, toxicity, instability and an enigmatic molecular mechanism of action. Herein we describe the development of a minimal QS-21 analogue that decouples adjuvant activity from toxicity and provides a powerful platform for mechanistic investigations. We found that the entire branched trisaccharide domain of QS-21 is dispensable for adjuvant activity and that the C4-aldehyde substituent, previously proposed to bind covalently to an unknown cellular target, is also not required. Biodistribution studies revealed that active adjuvants were retained preferentially at the injection site and the nearest draining lymph nodes compared with the attenuated variants. Overall, these studies have yielded critical insights into saponin structure-function relationships, provided practical synthetic access to non-toxic adjuvants, and established a platform for detailed mechanistic studies.

Development of a minimal saponin vaccine adjuvant based on QS-21

PubMed Central

Fernández-Tejada, Alberto; Chea, Eric K.; George, Constantine; Pillarsetty, NagaVaraKishore; Gardner, Jeffrey R.; Livingston, Philip O.; Ragupathi, Govind; Lewis, Jason S.; Tan, Derek S.; Gin, David Y.

2014-01-01

Adjuvants are materials added to vaccines to enhance the immunological response to an antigen. QS-21 is a natural product adjuvant under investigation in numerous vaccine clinical trials, but its use is constrained by scarcity, toxicity, instability, and an enigmatic molecular mechanism of action. Herein, we describe the development of a minimal QS-21 analogue that decouples adjuvant activity from toxicity and provides a powerful platform for mechanistic investigations. We found that the entire branched trisaccharide domain of QS-21 is dispensable for adjuvant activity and that the C4-aldehyde substituent, previously proposed to bind covalently to an unknown cellular target, is also not required. Biodistribution studies revealed that active adjuvants were retained at the injection site and nearest draining lymph nodes preferentially compared to attenuated variants. Overall, these studies have yielded critical insights into saponin structure–function relationships, provided practical synthetic access to non-toxic adjuvants, and established a platform for detailed mechanistic studies. PMID:24950335

Virus-Like Particle, Liposome, and Polymeric Particle-Based Vaccines against HIV-1

PubMed Central

Gao, Yong; Wijewardhana, Chanuka; Mann, Jamie F. S.

2018-01-01

It is acknowledged that vaccines remain the best hope for eliminating the HIV-1 epidemic. However, the failure to produce effective vaccine immunogens and the inability of conventional delivery strategies to elicit the desired immune responses remains a central theme and has ultimately led to a significant roadblock in HIV vaccine development. Consequently, significant efforts have been applied to generate novel vaccine antigens and delivery agents, which mimic viral structures for optimal immune induction. Here, we review the latest developments that have occurred in the nanoparticle vaccine field, with special emphasis on strategies that are being utilized to attain highly immunogenic, systemic, and mucosal anti-HIV humoral and cellular immune responses. This includes the design of novel immunogens, the central role of antigen-presenting cells, delivery routes, and biodistribution of nanoparticles to lymph nodes. In particular, we will focus on virus-like-particle formulations and their preclinical uses within the HIV prophylactic vaccine setting. PMID:29541072

From Conventional Radiotracer Tc-99(m) with Blue Dye to Indocyanine Green Fluorescence: A Comparison of Methods Towards Optimization of Sentinel Lymph Node Mapping in Early Stage Cervical Cancer for a Laparoscopic Approach.

PubMed

Buda, Alessandro; Papadia, Andrea; Zapardiel, Ignacio; Vizza, Enrico; Ghezzi, Fabio; De Ponti, Elena; Lissoni, Andrea Alberto; Imboden, Sara; Diestro, Maria Dolores; Verri, Debora; Gasparri, Maria Luisa; Bussi, Beatrice; Di Martino, Giampaolo; de la Noval, Begoña Diaz; Mueller, Michael; Crivellaro, Cinzia

2016-09-01

The credibility of sentinel lymph node (SLN) mapping is becoming increasingly more established in cervical cancer. We aimed to assess the sensitivity of SLN biopsy in terms of detection rate and bilateral mapping in women with cervical cancer by comparing technetium-99 radiocolloid (Tc-99(m)) and blue dye (BD) versus fluorescence mapping with indocyanine green (ICG). Data of patients with cervical cancer stage 1A2 to 1B1 from 5 European institutions were retrospectively reviewed. All centers used a laparoscopic approach with the same intracervical dye injection. Detection rate and bilateral mapping of ICG were compared, respectively, with results obtained by standard Tc-99(m) with BD. Overall, 76 (53 %) of 144 of women underwent preoperative SLN mapping with radiotracer and intraoperative BD, whereas 68 of (47 %) 144 patients underwent mapping using intraoperative ICG. The detection rate of SLN mapping was 96 % and 100 % for Tc-99(m) with BD and ICG, respectively. Bilateral mapping was achieved in 98.5 % for ICG and 76.3 % for Tc-99(m) with BD; this difference was statistically significant (p < 0.0001). The fluorescence SLN mapping with ICG achieved a significantly higher detection rate and bilateral mapping compared to standard radiocolloid and BD technique in women with early stage cervical cancer. Nodal staging with an intracervical injection of ICG is accurate, safe, and reproducible in patients with cervical cancer. Before replacing lymphadenectomy completely, the additional value of fluorescence SLN mapping on both perioperative morbidity and survival should be explored and confirmed by ongoing controlled trials.

Conversion of rod-shaped gold nanoparticles to spherical forms and their effect on biodistribution in tumor-bearing mice.

PubMed

Akiyama, Yasuyuki; Mori, Takeshi; Katayama, Yoshiki; Niidome, Takuro

2012-10-11

Gold nanorods that have an absorption band in the near-infrared region and a photothermal effect have been used as nanodevices for near-infrared imaging and thermal therapy. Choice of the optimal shape of gold nanorods which relates optical properties and in vivo biodistribution is important for their applications. In the present study, to investigate the relationship between the shape of gold nanorods and their biodistribution after intravenous injection, we first prepared two types of gold nanorods that had distinct aspect ratios but had the same volume, zeta potential, and PEG density on the gold surface. Biodistributions of the two types of gold nanorods after intravenous injection into tumor-bearing mice were then compared. Although a slight difference in accumulation in the spleen was observed, no significant difference was observed in the liver, lung, kidney, and tumors. These results suggest that biodistribution of the gold nanorods in the aspect ratio range of 1.7 to 5.0, diameter of 10 to 50 nm, and volume of approximately 4 × 103 nm3 was dependent mainly on surface characteristics, PEG density, and zeta potential.

Effects of concurrent drug therapy on technetium /sup 99m/Tc gluceptate biodistribution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hinkle, G.H.; Basmadjian, G.P.; Peek, C.

Drug interactions with /sup 99m/Tc gluceptate resulting in altered biodistribution were studied using chart review and animal tests. Charts of nine patients who had abnormal gallbladder uptake of technetium /sup 99m/Tc gluceptate during a two-year period were reviewed to obtain data such as concurrent drug therapy, primary diagnosis, and laboratory values. Adult New Zealand white rabbits were then used for testing the biodistribution of technetium /sup 99m/Tc gluceptate when administered concurrently with possibly interacting drugs identified in the chart review--penicillamine, penicillin G potassium, penicillin V potassium, acetaminophen, and trimethoprim-sulfamethoxazole. Chart review revealed no conclusive patterns of altered biodistribution associated withmore » other factors. The data did suggest the possibility that the five drugs listed above might cause increased hepatobiliary clearance of the radiopharmaceutical. Animal tests showed that i.v. penicillamine caused substantial distribution of radioactivity into the gallbladder and small bowel. Minimally increased gallbladder radioactivity occurred when oral acetaminophen and trimethoprim-sulfamethoxazole were administered concurrently. Oral and i.v. penicillins did not increase gallbladder activity. Penicillamine may cause substantial alteration of the biodistribution of technetium /sup 99m/Tc gluceptate.« less

High vertical resolution crosswell seismic imaging

DOEpatents

Lazaratos, Spyridon K.

1999-12-07

A method for producing high vertical resolution seismic images from crosswell data is disclosed. In accordance with one aspect of the disclosure, a set of vertically spaced, generally horizontally extending continuous layers and associated nodes are defined within a region between two boreholes. The specific number of nodes is selected such that the value of a particular characteristic of the subterranean region at each of the nodes is one which can be determined from the seismic data. Once values are established at the nodes, values of the particular characteristic are assigned to positions between the node points of each layer based on the values at node within that layer and without regard to the values at node points within any other layer. A seismic map is produced using the node values and the assigned values therebetween. In accordance with another aspect of the disclosure, an approximate model of the region is established using direct arrival traveltime data. Thereafter, the approximate model is adjusted using reflected arrival data. In accordance with still another aspect of the disclosure, correction is provided for well deviation. An associated technique which provides improvements in ray tracing is also disclosed.

Sentinel lymph node surgery after neoadjuvant chemotherapy in patients with T2 to T4, N0 and N1 breast cancer.

PubMed

Andreis, D; Bonardi, S; Allevi, G; Aguggini, S; Gussago, F; Milani, M; Strina, C; Spada, D; Ferrero, G; Ungari, M; Rocca, A; Nanni, O; Roviello, G; Berruti, A; Harris, A L; Fox, S B; Roviello, F; Polom, K; Bottini, A; Generali, D

2016-10-01

Histological status of axillary lymph nodes is an important prognostic factor in patients receiving surgery for breast cancer (BC). Sentinel lymph node (SLN) biopsy (B) has rapidly replaced axillary lymph node dissection (ALND), and is now the standard of care for axillary staging in patients with clinically node-negative (N0) operable BC. The aim of this study is to compare pretreatment lymphoscintigraphy with a post primary systemic treatment (PST) scan in order to reduce the false-negative rates for SLNB. In this single-institution study we considered 170 consecutive T2-4 N0-1 M0 BC patients treated with anthracycline-based PST. At the time of incisional biopsy, we performed sentinel lymphatic mapping. After PST, all patients repeated lymphoscintigraphy with the same methodology. During definitive surgery we performed further sentinel lymphatic mapping, SLNB and ALND. The SLN was removed in 158/170 patients giving an identification rate of 92.9% (95% confidence interval (CI) = 88.0-96.3%) and a false-negative rate of 14.0% (95% CI = 6.3-25.8%). SLNB revealed a sensitivity of 86.0% (95% CI = 74.2-93.7%), an accuracy of 94.9% (95% CI = 90.3-97.8%) and a negative predictive value of 92.7% (95% CI = 86.1-96.8%). Identification rate, sensitivity and accuracy are in accordance with other studies on SLNB after PST, even after clinically negative node conversion following PST. This study confirms that diagnostic biopsy and neoadjuvant chemotherapy maintain breast lymphatic drainage unaltered. Copyright © 2016 Elsevier Ltd. All rights reserved.

[The clinical value of sentinel lymph node detection in laryngeal and hypopharyngeal carcinoma patients with clinically negative neck by methylene blue method and radiolabeled tracer method].

PubMed

Zhao, Xin; Xiao, Dajiang; Ni, Jianming; Zhu, Guochen; Yuan, Yuan; Xu, Ting; Zhang, Yongsheng

2014-11-01

To investigate the clinical value of sentinel lymph node (SLN) detection in laryngeal and hypopharyngeal carcinoma patients with clinically negative neck (cN0) by methylene blue method, radiolabeled tracer method and combination of these two methods. Thirty-three patients with cN0 laryngeal carcinoma and six patients with cN0 hypopharyngeal carcinoma underwent SLN detection using both of methylene blue and radiolabeled tracer method. All these patients were accepted received the injection of radioactive isotope 99 Tc(m)-sulfur colloid (SC) and methylene blue into the carcinoma before surgery, then all these patients underwent intraopertive lymphatic mapping with a handheld gamma-detecting probe and blue-dyed SLN. After the mapping of SLN, selected neck dissections and tumor resections were peformed. The results of SLN detection by radiolabeled tracer, dye and combination of both methods were compared. The detection rate of SLN by radiolabeled tracer, methylene blue and combined method were 89.7%, 79.5%, 92.3% respectively. The number of detected SLN was significantly different between radiolabeled tracer method and combined method, and also between methylene blue method and combined method. The detection rate of methylene blue and radiolabeled tracer method were significantly different from combined method (P < 0.05). Nine patients were found to have lymph node metastasis by final pathological examination. The accuracy and negative rate of SLN detection of the combined method were 97.2% and 11.1%. The combined method using radiolabeled tracer and methylene blue can improve the detection rate and accuracy of sentinel lymph node detection. Furthermore, sentinel lymph node detection can accurately represent the cervical lymph node status in cN0 laryngeal and hypopharyngeal carcinoma.

Diagnostic performance of magnetic resonance imaging and 3D endoanal ultrasound in detection, staging and assessment post treatment, in anal cancer.

PubMed

Reginelli, Alfonso; Granata, Vincenza; Fusco, Roberta; Granata, Francesco; Rega, Daniela; Roberto, Luca; Pellino, Gianluca; Rotondo, Antonio; Selvaggi, Francesco; Izzo, Francesco; Petrillo, Antonella; Grassi, Roberto

2017-04-04

We compared Magnetic Resonance Imaging (MRI) and 3D Endoanal Ultrasound (EAUS) imaging performance to confirm anal carcinoma and to monitor treatment response.58 patients with anal cancer were retrospectively enrolled. All patients underwent clinical examination, anoscopic examination; EAUS and contrast-enhanced MRI study before and after treatment. Four radiologists evaluated the presence of lesions, using a 4-point confidence scale, features of the lesion and nodes on EAUS images, T1-weighted (T1-W), T2-weighted (T2-W) and diffusion-weighted images (DWI) signal intensity (SI), the apparent diffusion coefficient (ADC) map for nodes and lesion, as well as enhancement pattern during dynamic MRI were assessed.All lesions were detected by EAUS while MRI detected 93.1% of anal cancer. MRI showed a good correlation with EAUS, anoscopy and clinical examination. The residual tissue not showed significant difference in EAUS assessment and T2-W SI in pre and post treatment. We found significant difference in dynamic study, in SI of DWI, in ADC map and values among responder's patients in pre and post treatment. The neoplastic nodes were hypoecoic on EAUS, with hyperintense signal on T2-W sequences and hypointense signal on T1-W. The neoplastic nodes showed SI on DWI sequences and ADC value similar to anal cancer. We found significant difference in nodes status in pre and post therapy on DWI data.3D EAUS and MRI are accurate techniques in anal cancer staging, although EAUS is more accurate than MRI for T1 stage. MRI allows correct detection of neoplastic nodes and can properly stratify patients into responders or non responders.

Expert networks in CLIPS

NASA Technical Reports Server (NTRS)

Hruska, S. I.; Dalke, A.; Ferguson, J. J.; Lacher, R. C.

1991-01-01

Rule-based expert systems may be structurally and functionally mapped onto a special class of neural networks called expert networks. This mapping lends itself to adaptation of connectionist learning strategies for the expert networks. A parsing algorithm to translate C Language Integrated Production System (CLIPS) rules into a network of interconnected assertion and operation nodes has been developed. The translation of CLIPS rules to an expert network and back again is illustrated. Measures of uncertainty similar to those rules in MYCIN-like systems are introduced into the CLIPS system and techniques for combining and hiring nodes in the network based on rule-firing with these certainty factors in the expert system are presented. Several learning algorithms are under study which automate the process of attaching certainty factors to rules.

Mannosylated dextran derivatives labeled with fac-[M(CO)₃]+ (M = (99m)Tc, Re) for specific targeting of sentinel lymph node.

PubMed

Morais, Maurício; Subramanian, Suresh; Pandey, Usha; Samuel, Grace; Venkatesh, Meera; Martins, Manuel; Pereira, Sérgio; Correia, João D G; Santos, Isabel

2011-04-04

Despite being widely used in the clinical setting for sentinel lymph node detection (SLND), (99m)Tc-based colloids (e.g., (99m)Tc-human serum albumin colloids) present a set of properties that are far from ideal. Aiming to design novel compounds with improved biological properties, we describe herein the first class of fully characterized (99m)Tc(CO)₃-mannosylated dextran derivatives with adequate features for SLND. Dextran derivatives, containing the same number of pendant mannose units (13) and a variable number (n) of tridentate chelators (9, n = 1; 10, n = 4, 11, n= 12), have been synthesized and fully characterized. Radiolabeled polymers of the type fac-[(99m)Tc(CO)₃(k³-L)] (12, L = 9, 13, L = 10, 14, L = 11) have been obtained quantitatively in high radiochemical purity (≥ 98%) upon reaction of the dextran derivatives with fac-[(99m)Tc(CO)₃(H₂O)₃]+. The highly stable compounds 13 and 14 were identified by comparing their HPLC chromatograms with the ones obtained for the corresponding rhenium surrogates fac-[Re(CO)₃(k³-10)] (13a) and fac-[Re(CO)₃(k³-11)] (14a), which have been characterized both at the chemical (NMR and IR spectroscopy, and HPLC) and physical level (DLS, AFM and LDV). Compounds 13a and 14a present a positive zeta potential (+ 7.1 mV, pH 7.4) and a hydrodynamic diameter in the range 8.4-8.7 nm. Scintigraphic imaging and biodistribution studies in Wistar rats have shown good accumulation in the sentinel node at 60 min postinjection (6.71 ± 2.35%, 13; and 7.53 ± 0.69%, 14), with significant retention up to 180 min. A clear delineation of the sentinel lymph node without significant washout to other regions was observed in the scintigraphic images. The popliteal extraction of 94.47 ± 2.45% for 14 at 1 h postinjection, as compared to 61.81 ± 2.4% for 13, indicated that 14 is a very promising compound to be further explored as SLN imaging agent.

Knowledge Representation for Decision Making Agents

DTIC Science & Technology

2013-07-15

knowledge map. This knowledge map is a dictionary data structure called tmap in the code. It represents a network of locations with a number [0,1...fillRandom(): Informed initial tmap distribution (randomly generated per node) with belief one. • initialBelief = 3 uses fillCenter(): normal...triggered on AllMyFMsHaveBeenInitialized. 2. Executes main.py • Initializes knowledge map labeled tmap . • Calls initialize search() – resets distanceTot and

Sentinel Node Mapping Using Indocyanine Green and Near-infrared Fluorescence Imaging Technology for Uterine Malignancies: Preliminary Experience With the Da Vinci Xi System.

PubMed

Siesto, Gabriele; Romano, Fabrizio; Fiamengo, Barbara; Vitobello, Domenico

2016-01-01

Sentinel lymph node (SLN) mapping has emerged as the new frontier for the surgical staging of apparently early-stage cervical and endometrial cancer. Different colorimetric and radioactive tracers, alone and in combination, have been proposed with encouraging results. Fluorometric mapping using indocyanine green (ICG) appears to be a suitable and attractive alternative to provide reliable staging [1-4]. In this video, we present the technique of SLN mapping in 2 cases (1 endometrial and 1 cervical cancer, respectively) using ICG and the near-infrared technology provided by the newest Da Vinci Xi robotic system (Intuitive Surgical Inc., Sunnyvale, CA). Together we report the results of our preliminary experience on the first 20 cases performed. The new robotic Da Vinci Xi system was available at our institution since May 2015. Upon institutional review board/ethical committee approval, all consecutive patients with early-stage endometrial and cervical cancer who were judged suitable for robotic surgery have been enrolled for SLN mapping with ICG. We adopted the Memorial Sloan Kettering Cancer Center SLN algorithm; the tracer was delivered into the cervix in all cases. Four milliliters (1.25 mg/mL) of ICG was injected divided into the 3- and 9-o'clock positions of the cervix alone, with 1 mL deep into the stroma and 1 mL submucosally at the skin incision. Sentinel lymph nodes were examined with a protocol including both ultrastaging with immunohistochemistry [3] and 1-step nucleic acid amplification assay [5,6] under a parallel protocol of study. During the study period, 20 cases were managed; 14 and 6 patients had endometrial and cervical cancer, respectively. SLN was detected in all cases (20/20, 100%). Bilateral SLNs were detected in 17 of 20 (85.0%) cases. Based on preoperative and intraoperative findings, 13 (65.0%) patients received systematic pelvic lymphadenectomy after SLN mapping. Three (15.0%) patients had microscopic nodal metastases on SLN. No patients had positive regional nodes other than SLN. No perioperative complications were recorded. SLN mapping has been acknowledged by the National Comprehensive Cancer Network guidelines as a viable option for the management of selected uterine malignancies [7,8]. Currently, the near-infrared technology built in the Da Vinci Xi system provides an enhanced real-time imaging system that improves the advantages given by ICG. Together with our experience, these conditions indicate that SLN mapping is an effective and safe procedure with high overall detection and low false-negative rates. Copyright © 2016 AAGL. Published by Elsevier Inc. All rights reserved.

Biodistribution of amino-functionalized diamond nanoparticles. In vivo studies based on 18F radionuclide emission.

PubMed

Rojas, Santiago; Gispert, Juan D; Martín, Roberto; Abad, Sergio; Menchón, Cristina; Pareto, Deborah; Víctor, Víctor M; Alvaro, Mercedes; García, Hermenegildo; Herance, J Raúl

2011-07-26

Nanoparticles have been proposed for several biomedical applications; however, in vivo biodistribution studies to confirm their potential are scarce. Nanodiamonds are carbon nanoparticles that have been recently proposed as a promising biomaterial. In this study, we labeled nanodiamonds with (18)F to study their in vivo biodistribution by positron emission tomography. Moreover, the impact on the biodistribution of their kinetic particle size and of the surfactant agents has been evaluated. Radiolabeled diamond nanoparticles accumulated mainly in the lung, spleen, and liver and were excreted into the urinary tract. The addition of surfactant agents did not lead to significant changes in this pattern, with the exception of a slight reduction in the urinary excretion rate. On the other hand, after filtration of the radiolabeled diamond nanoparticles to remove those with a larger kinetic size, the uptake in the lung and spleen was completely inhibited and significantly reduced in the liver.

Tracking short-term biodistribution and long-term clearance of SPIO tracers in magnetic particle imaging

NASA Astrophysics Data System (ADS)

Keselman, Paul; Yu, Elaine Y.; Zhou, Xinyi Y.; Goodwill, Patrick W.; Chandrasekharan, Prashant; Ferguson, R. Matthew; Khandhar, Amit P.; Kemp, Scott J.; Krishnan, Kannan M.; Zheng, Bo; Conolly, Steven M.

2017-05-01

Magnetic particle imaging (MPI) is an emerging tracer-based medical imaging modality that images non-radioactive, kidney-safe superparamagnetic iron oxide (SPIO) tracers. MPI offers quantitative, high-contrast and high-SNR images, so MPI has exceptional promise for applications such as cell tracking, angiography, brain perfusion, cancer detection, traumatic brain injury and pulmonary imaging. In assessing MPI’s utility for applications mentioned above, it is important to be able to assess tracer short-term biodistribution as well as long-term clearance from the body. Here, we describe the biodistribution and clearance for two commonly used tracers in MPI: Ferucarbotran (Meito Sangyo Co., Japan) and LS-oo8 (LodeSpin Labs, Seattle, WA). We successfully demonstrate that 3D MPI is able to quantitatively assess short-term biodistribution, as well as long-term tracking and clearance of these tracers in vivo.

Diagnostic and prognostic value of additional SPECT/CT in sentinel lymph node mapping in breast cancer patients.

PubMed

Stanzel, Susanne; Pernthaler, Birgit; Schwarz, Thomas; Bjelic-Radisic, Vesna; Kerschbaumer, Stefan; Aigner, Reingard M

2018-06-01

of the study was to demonstrate the diagnostic and prognostic value of SPECT/CT in sentinel lymph node mapping (SLNM) in patients with invasive breast cancer. 114 patients with invasive breast cancer with clinically negative lymph nodes were included in this retrospective study as they were referred for SLNM with 99m Tc-nanocolloid. Planar image acquisition was accomplished in a one-day or two-day protocol depending on the schedule of the surgical procedure. Low dose SPECT/CT was performed after the planar images. The sentinel lymph node biopsy (SLNB) was considered false negative if a primary recurrence developed within 12 months after SLNB in the axilla from which a tumor-free SLN had been removed. Between December 2009 and December 2011, 114 patients (pts.) underwent SLNM with additional SPECT/CT. Planar imaging identified in 109 pts. 139 SLNs, which were tumor-positive in 42 nodes (n = 41 pts.). SPECT/CT identified in 81 pts. 151 additional SLNs, of which 19 were tumor-positive and led to therapy change (axillary lymph node dissection) in 11 pts. (9.6 %). Of overall 61 tumor-positive SLNs (n = 52 pts.) SPECT/CT detected all, whereas planar imaging detected only 42 of 61 ( P < 0.0001). No patient had lymph node metastasis within 12 months after SLNB in the axilla from which a tumor-free SLN had been removed resulting in a false-negative rate of 0 %. The local relapse rate was 1.8 % leading to a 4-year disease-free survival rate of 90 %. Among patients with breast cancer, the use of SPECT/CT-aided SLNM correlated due to a better anatomical localization and identification of planar not visible SLNs with a higher detection rate of SLNs. This led to therapeutic consequences and an excellent false-negative and 4-year disease-free survival rate. Schattauer GmbH.

Design and development of a medical big data processing system based on Hadoop.

PubMed

Yao, Qin; Tian, Yu; Li, Peng-Fei; Tian, Li-Li; Qian, Yang-Ming; Li, Jing-Song

2015-03-01

Secondary use of medical big data is increasingly popular in healthcare services and clinical research. Understanding the logic behind medical big data demonstrates tendencies in hospital information technology and shows great significance for hospital information systems that are designing and expanding services. Big data has four characteristics--Volume, Variety, Velocity and Value (the 4 Vs)--that make traditional systems incapable of processing these data using standalones. Apache Hadoop MapReduce is a promising software framework for developing applications that process vast amounts of data in parallel with large clusters of commodity hardware in a reliable, fault-tolerant manner. With the Hadoop framework and MapReduce application program interface (API), we can more easily develop our own MapReduce applications to run on a Hadoop framework that can scale up from a single node to thousands of machines. This paper investigates a practical case of a Hadoop-based medical big data processing system. We developed this system to intelligently process medical big data and uncover some features of hospital information system user behaviors. This paper studies user behaviors regarding various data produced by different hospital information systems for daily work. In this paper, we also built a five-node Hadoop cluster to execute distributed MapReduce algorithms. Our distributed algorithms show promise in facilitating efficient data processing with medical big data in healthcare services and clinical research compared with single nodes. Additionally, with medical big data analytics, we can design our hospital information systems to be much more intelligent and easier to use by making personalized recommendations.

The use of isotope injections in sentinel node biopsy for breast cancer: are the 1- and 2-day protocols equally effective?

PubMed

Dodia, Nazera; El-Sharief, Deena; Kirwan, Cliona C

2015-01-01

Sentinel lymph nodes are mapped using (99m)Technetium, injected on day of surgery (1-day protocol) or day before (2-day protocol). This retrospective cohort study compares efficacy between the two protocols. Histopathology for all unilateral sentinel lymph node biopsies (March 2012-March 2013) in a single centre were reviewed. Number of sentinel lymph nodes, non-sentinel lymph nodes and pathology was compared. 2/270 (0.7 %) in 1-day protocol and 8/192 (4 %) in 2-day protocol had no sentinel lymph nodes removed (p = 0.02). The median (range) number of sentinel lymph nodes removed per patient was 2 (0-7) and 1 (0-11) in the 1- and 2-day protocols respectively (p = 0.08). There was a trend for removing more non-sentinel lymph nodes in 2-day protocol [1-day: 52/270 (19 %); 2-day: 50/192 (26 %), p = 0.07]. Using 2-day, sentinel lymph node identification failure rate is higher, although within acceptable rates. The 1 and 2 day protocols are both effective, therefore choice of protocol should be driven by patient convenience and hospital efficiency. However, this study raises the possibility that 1-day may be preferable when higher sentinel lymph node count is beneficial, for example following neoadjuvant chemotherapy.

Dense volumetric detection and segmentation of mediastinal lymph nodes in chest CT images

NASA Astrophysics Data System (ADS)

Oda, Hirohisa; Roth, Holger R.; Bhatia, Kanwal K.; Oda, Masahiro; Kitasaka, Takayuki; Iwano, Shingo; Homma, Hirotoshi; Takabatake, Hirotsugu; Mori, Masaki; Natori, Hiroshi; Schnabel, Julia A.; Mori, Kensaku

2018-02-01

We propose a novel mediastinal lymph node detection and segmentation method from chest CT volumes based on fully convolutional networks (FCNs). Most lymph node detection methods are based on filters for blob-like structures, which are not specific for lymph nodes. The 3D U-Net is a recent example of the state-of-the-art 3D FCNs. The 3D U-Net can be trained to learn appearances of lymph nodes in order to output lymph node likelihood maps on input CT volumes. However, it is prone to oversegmentation of each lymph node due to the strong data imbalance between lymph nodes and the remaining part of the CT volumes. To moderate the balance of sizes between the target classes, we train the 3D U-Net using not only lymph node annotations but also other anatomical structures (lungs, airways, aortic arches, and pulmonary arteries) that can be extracted robustly in an automated fashion. We applied the proposed method to 45 cases of contrast-enhanced chest CT volumes. Experimental results showed that 95.5% of lymph nodes were detected with 16.3 false positives per CT volume. The segmentation results showed that the proposed method can prevent oversegmentation, achieving an average Dice score of 52.3 +/- 23.1%, compared to the baseline method with 49.2 +/- 23.8%, respectively.

Tracking targeted bimodal nanovaccines: immune responses and routing in cells, tissue, and whole organism.

PubMed

Cruz, Luis J; Tacken, Paul J; Zeelenberg, Ingrid S; Srinivas, Mangala; Bonetto, Fernando; Weigelin, Bettina; Eich, Christina; de Vries, I Jolanda; Figdor, Carl G

2014-12-01

Dendritic cells (DCs) are the most potent antigen-presenting cells (APCs), involved in the induction of immunity and currently exploited for antitumor immunotherapies. An optimized noninvasive imaging modality capable of determining and quantifying DC-targeted nanoparticle (NP) trajectories could provide valuable information regarding therapeutic vaccine outcome. Here, targeted poly(d,l-lactide-co-glycolide) nanoparticles (PLGA NPs) recognizing DC receptors were equipped with superparamagnetic iron oxide particles (SPIO) or gold nanoparticles with fluorescently labeled antigen. The fluorescent label allowed for rapid analysis and quantification of DC-specific uptake of targeted PLGA NPs in comparison to uptake by other cells. Transmission electron microscopy (TEM) showed that a fraction of the encapsulated antigen reached the lysosomal compartment of DCs, where SPIO and gold were already partially released. However, part of the PLGA NPs localized within the cytoplasm, as confirmed by confocal microscopy. DCs targeted with NPs carrying SPIO or fluorescent antigen were detected within lymph nodes as early as 1 h after injection by magnetic resonance imaging (MRI). Despite the fact that targeting did not markedly affect PLGA NP biodistribution on organism and tissue level, it increased delivery of NPs to DCs residing in peripheral lymph nodes and resulted in enhanced T cell proliferation. In conclusion, two imaging agents within a single carrier allows tracking of targeted PLGA NPs at the subcellular, cellular, and organismal levels, thereby facilitating the rational design of in vivo targeted vaccination strategies.

Unsupervised learning in general connectionist systems.

PubMed

Dente, J A; Mendes, R Vilela

1996-01-01

There is a common framework in which different connectionist systems may be treated in a unified way. The general system in which they may all be mapped is a network which, in addition to the connection strengths, has an adaptive node parameter controlling the output intensity. In this paper we generalize two neural network learning schemes to networks with node parameters. In generalized Hebbian learning we find improvements to the convergence rate for small eigenvalues in principal component analysis. For competitive learning the use of node parameters also seems useful in that, by emphasizing or de-emphasizing the dominance of winning neurons, either improved robustness or discrimination is obtained.

Using a local low rank plus sparse reconstruction to accelerate dynamic hyperpolarized 13C imaging using the bSSFP sequence.

PubMed

Milshteyn, Eugene; von Morze, Cornelius; Reed, Galen D; Shang, Hong; Shin, Peter J; Larson, Peder E Z; Vigneron, Daniel B

2018-05-01

Acceleration of dynamic 2D (T 2 Mapping) and 3D hyperpolarized 13 C MRI acquisitions using the balanced steady-state free precession sequence was achieved with a specialized reconstruction method, based on the combination of low rank plus sparse and local low rank reconstructions. Methods were validated using both retrospectively and prospectively undersampled in vivo data from normal rats and tumor-bearing mice. Four-fold acceleration of 1-2 mm isotropic 3D dynamic acquisitions with 2-5 s temporal resolution and two-fold acceleration of 0.25-1 mm 2 2D dynamic acquisitions was achieved. This enabled visualization of the biodistribution of [2- 13 C]pyruvate, [1- 13 C]lactate, [ 13 C,  15 N 2 ]urea, and HP001 within heart, kidneys, vasculature, and tumor, as well as calculation of high resolution T 2 maps. Copyright © 2018 Elsevier Inc. All rights reserved.

Secure chaotic map based block cryptosystem with application to camera sensor networks.

PubMed

Guo, Xianfeng; Zhang, Jiashu; Khan, Muhammad Khurram; Alghathbar, Khaled

2011-01-01

Recently, Wang et al. presented an efficient logistic map based block encryption system. The encryption system employs feedback ciphertext to achieve plaintext dependence of sub-keys. Unfortunately, we discovered that their scheme is unable to withstand key stream attack. To improve its security, this paper proposes a novel chaotic map based block cryptosystem. At the same time, a secure architecture for camera sensor network is constructed. The network comprises a set of inexpensive camera sensors to capture the images, a sink node equipped with sufficient computation and storage capabilities and a data processing server. The transmission security between the sink node and the server is gained by utilizing the improved cipher. Both theoretical analysis and simulation results indicate that the improved algorithm can overcome the flaws and maintain all the merits of the original cryptosystem. In addition, computational costs and efficiency of the proposed scheme are encouraging for the practical implementation in the real environment as well as camera sensor network.

Secure Chaotic Map Based Block Cryptosystem with Application to Camera Sensor Networks

PubMed Central

Guo, Xianfeng; Zhang, Jiashu; Khan, Muhammad Khurram; Alghathbar, Khaled

2011-01-01

Recently, Wang et al. presented an efficient logistic map based block encryption system. The encryption system employs feedback ciphertext to achieve plaintext dependence of sub-keys. Unfortunately, we discovered that their scheme is unable to withstand key stream attack. To improve its security, this paper proposes a novel chaotic map based block cryptosystem. At the same time, a secure architecture for camera sensor network is constructed. The network comprises a set of inexpensive camera sensors to capture the images, a sink node equipped with sufficient computation and storage capabilities and a data processing server. The transmission security between the sink node and the server is gained by utilizing the improved cipher. Both theoretical analysis and simulation results indicate that the improved algorithm can overcome the flaws and maintain all the merits of the original cryptosystem. In addition, computational costs and efficiency of the proposed scheme are encouraging for the practical implementation in the real environment as well as camera sensor network. PMID:22319371

Lymphatic mapping for gastric adenocarcinoma.

PubMed

Hundley, Jon C; Shen, Perry; Shiver, Stephen A; Geisinger, Kim R; Levine, Edward A

2002-11-01

The role of lymphadenectomy for gastric carcinoma has been debated for decades. Lymphatic mapping has revolutionized the treatment of melanoma and breast cancer. However, its potential utility in guiding lymphadenectomy for gastric carcinoma is unknown. Therefore we initiated a trial to investigate lymphatic mapping for gastric carcinoma at Wake Forest University Baptist Medical Center. Lymphatic mapping for gastric carcinoma was attempted in 14 cases of gastric carcinoma. Mapping was performed by perilesional injection of isosulfan blue and the first node in the draining basin was harvested and sent fresh to pathology. Sentinel lymph nodes (SLNs) were evaluated by hematoxylin and eosin (H&E) staining. Immunohistochemical analysis was performed on all SLNs that were found to be negative on initial histologic studies. Radical gastrectomy with celiac node dissection was performed in all cases. SLNs were identified in 14 cases. In one case the technique was abandoned because of bulk nodal disease. The average number of SLNs found in each case was 2.8 with a range of one to five. Eight of 14 patients were found to have SLNs positive for metastatic carcinoma. In seven of these patients pathologic analysis of the final resection specimen confirmed the presence of nodal disease. In one case carcinoma was found in a SLN on touch preparation and no nodal disease was noted in the resection specimen. Immunohistochemical studies performed on SLNs found to be negative on initial H&E histologic analysis failed to reveal the presence of carcinoma. The overall sensitivity and specificity were found to be 72.7 and 75 per cent, respectively. Lymphatic mapping is technically possible in the setting of gastric carcinoma and SLNs can be successfully identified in the majority of cases. Upstaging occurred in one case which may have ramifications for adjuvant therapy. SLN positivity accurately predicts the presence of additional nodal disease beyond the SLN in the final resection specimen (positive predictive value 89%). However, SLN negativity does not definitively prove that the remaining nodal basin is free of disease (negative predictive value 50%). Lymphatic mapping for gastric carcinoma is a promising technique worthy of further investigation.

Applications of the MapReduce programming framework to clinical big data analysis: current landscape and future trends.

PubMed

Mohammed, Emad A; Far, Behrouz H; Naugler, Christopher

2014-01-01

The emergence of massive datasets in a clinical setting presents both challenges and opportunities in data storage and analysis. This so called "big data" challenges traditional analytic tools and will increasingly require novel solutions adapted from other fields. Advances in information and communication technology present the most viable solutions to big data analysis in terms of efficiency and scalability. It is vital those big data solutions are multithreaded and that data access approaches be precisely tailored to large volumes of semi-structured/unstructured data. THE MAPREDUCE PROGRAMMING FRAMEWORK USES TWO TASKS COMMON IN FUNCTIONAL PROGRAMMING: Map and Reduce. MapReduce is a new parallel processing framework and Hadoop is its open-source implementation on a single computing node or on clusters. Compared with existing parallel processing paradigms (e.g. grid computing and graphical processing unit (GPU)), MapReduce and Hadoop have two advantages: 1) fault-tolerant storage resulting in reliable data processing by replicating the computing tasks, and cloning the data chunks on different computing nodes across the computing cluster; 2) high-throughput data processing via a batch processing framework and the Hadoop distributed file system (HDFS). Data are stored in the HDFS and made available to the slave nodes for computation. In this paper, we review the existing applications of the MapReduce programming framework and its implementation platform Hadoop in clinical big data and related medical health informatics fields. The usage of MapReduce and Hadoop on a distributed system represents a significant advance in clinical big data processing and utilization, and opens up new opportunities in the emerging era of big data analytics. The objective of this paper is to summarize the state-of-the-art efforts in clinical big data analytics and highlight what might be needed to enhance the outcomes of clinical big data analytics tools. This paper is concluded by summarizing the potential usage of the MapReduce programming framework and Hadoop platform to process huge volumes of clinical data in medical health informatics related fields.

Man-Made Object Extraction from Remote Sensing Imagery by Graph-Based Manifold Ranking

NASA Astrophysics Data System (ADS)

He, Y.; Wang, X.; Hu, X. Y.; Liu, S. H.

2018-04-01

The automatic extraction of man-made objects from remote sensing imagery is useful in many applications. This paper proposes an algorithm for extracting man-made objects automatically by integrating a graph model with the manifold ranking algorithm. Initially, we estimate a priori value of the man-made objects with the use of symmetric and contrast features. The graph model is established to represent the spatial relationships among pre-segmented superpixels, which are used as the graph nodes. Multiple characteristics, namely colour, texture and main direction, are used to compute the weights of the adjacent nodes. Manifold ranking effectively explores the relationships among all the nodes in the feature space as well as initial query assignment; thus, it is applied to generate a ranking map, which indicates the scores of the man-made objects. The man-made objects are then segmented on the basis of the ranking map. Two typical segmentation algorithms are compared with the proposed algorithm. Experimental results show that the proposed algorithm can extract man-made objects with high recognition rate and low omission rate.

Node, Node-Link, and Node-Link-Group Diagrams: An Evaluation.

PubMed

Saket, Bahador; Simonetto, Paolo; Kobourov, Stephen; Börner, Katy

2014-12-01

Effectively showing the relationships between objects in a dataset is one of the main tasks in information visualization. Typically there is a well-defined notion of distance between pairs of objects, and traditional approaches such as principal component analysis or multi-dimensional scaling are used to place the objects as points in 2D space, so that similar objects are close to each other. In another typical setting, the dataset is visualized as a network graph, where related nodes are connected by links. More recently, datasets are also visualized as maps, where in addition to nodes and links, there is an explicit representation of groups and clusters. We consider these three Techniques, characterized by a progressive increase of the amount of encoded information: node diagrams, node-link diagrams and node-link-group diagrams. We assess these three types of diagrams with a controlled experiment that covers nine different tasks falling broadly in three categories: node-based tasks, network-based tasks and group-based tasks. Our findings indicate that adding links, or links and group representations, does not negatively impact performance (time and accuracy) of node-based tasks. Similarly, adding group representations does not negatively impact the performance of network-based tasks. Node-link-group diagrams outperform the others on group-based tasks. These conclusions contradict results in other studies, in similar but subtly different settings. Taken together, however, such results can have significant implications for the design of standard and domain snecific visualizations tools.

Thoracic lymph node station recognition on CT images based on automatic anatomy recognition with an optimal parent strategy

NASA Astrophysics Data System (ADS)

Xu, Guoping; Udupa, Jayaram K.; Tong, Yubing; Cao, Hanqiang; Odhner, Dewey; Torigian, Drew A.; Wu, Xingyu

2018-03-01

Currently, there are many papers that have been published on the detection and segmentation of lymph nodes from medical images. However, it is still a challenging problem owing to low contrast with surrounding soft tissues and the variations of lymph node size and shape on computed tomography (CT) images. This is particularly very difficult on low-dose CT of PET/CT acquisitions. In this study, we utilize our previous automatic anatomy recognition (AAR) framework to recognize the thoracic-lymph node stations defined by the International Association for the Study of Lung Cancer (IASLC) lymph node map. The lymph node stations themselves are viewed as anatomic objects and are localized by using a one-shot method in the AAR framework. Two strategies have been taken in this paper for integration into AAR framework. The first is to combine some lymph node stations into composite lymph node stations according to their geometrical nearness. The other is to find the optimal parent (organ or union of organs) as an anchor for each lymph node station based on the recognition error and thereby find an overall optimal hierarchy to arrange anchor organs and lymph node stations. Based on 28 contrast-enhanced thoracic CT image data sets for model building, 12 independent data sets for testing, our results show that thoracic lymph node stations can be localized within 2-3 voxels compared to the ground truth.

Energy Efficient Real-Time Scheduling Using DPM on Mobile Sensors with a Uniform Multi-Cores

PubMed Central

Kim, Youngmin; Lee, Chan-Gun

2017-01-01

In wireless sensor networks (WSNs), sensor nodes are deployed for collecting and analyzing data. These nodes use limited energy batteries for easy deployment and low cost. The use of limited energy batteries is closely related to the lifetime of the sensor nodes when using wireless sensor networks. Efficient-energy management is important to extending the lifetime of the sensor nodes. Most effort for improving power efficiency in tiny sensor nodes has focused mainly on reducing the power consumed during data transmission. However, recent emergence of sensor nodes equipped with multi-cores strongly requires attention to be given to the problem of reducing power consumption in multi-cores. In this paper, we propose an energy efficient scheduling method for sensor nodes supporting a uniform multi-cores. We extend the proposed T-Ler plane based scheduling for global optimal scheduling of a uniform multi-cores and multi-processors to enable power management using dynamic power management. In the proposed approach, processor selection for a scheduling and mapping method between the tasks and processors is proposed to efficiently utilize dynamic power management. Experiments show the effectiveness of the proposed approach compared to other existing methods. PMID:29240695

The added value of a portable gamma camera for intraoperative detection of sentinel lymph node in squamous cell carcinoma of the oral cavity: A case report.

PubMed

Mayoral, M; Paredes, P; Sieira, R; Vidal-Sicart, S; Marti, C; Pons, F

2014-01-01

The use of sentinel lymph node biopsy in squamous cell carcinoma of the oral cavity is still subject to debate although some studies have reported its feasibility. The main reason for this debate is probably due to the high false-negative rate for floor-of-mouth tumors per se. We report the case of a 54-year-old man with a T1N0 floor-of-mouth squamous cell carcinoma who underwent the sentinel lymph node procedure. Lymphoscintigraphy and SPECT/CT imaging were performed for lymphatic mapping with a conventional gamma camera. Sentinel lymph nodes were identified at right Ib, left IIa and Ia levels. However, these sentinel lymph nodes were difficult to detect intraoperatively with a gamma probe owing to the activity originating from the injection site. The use of a portable gamma camera made it possible to localize and excise all the sentinel lymph nodes. This case demonstrates the usefulness of this tool to improve sentinel lymph node detecting in floor-of-mouth tumors, especially those close to the injection area. Copyright © 2013 Elsevier España, S.L. and SEMNIM. All rights reserved.

node2vec: Scalable Feature Learning for Networks

PubMed Central

Grover, Aditya; Leskovec, Jure

2016-01-01

Prediction tasks over nodes and edges in networks require careful effort in engineering features used by learning algorithms. Recent research in the broader field of representation learning has led to significant progress in automating prediction by learning the features themselves. However, present feature learning approaches are not expressive enough to capture the diversity of connectivity patterns observed in networks. Here we propose node2vec, an algorithmic framework for learning continuous feature representations for nodes in networks. In node2vec, we learn a mapping of nodes to a low-dimensional space of features that maximizes the likelihood of preserving network neighborhoods of nodes. We define a flexible notion of a node’s network neighborhood and design a biased random walk procedure, which efficiently explores diverse neighborhoods. Our algorithm generalizes prior work which is based on rigid notions of network neighborhoods, and we argue that the added flexibility in exploring neighborhoods is the key to learning richer representations. We demonstrate the efficacy of node2vec over existing state-of-the-art techniques on multi-label classification and link prediction in several real-world networks from diverse domains. Taken together, our work represents a new way for efficiently learning state-of-the-art task-independent representations in complex networks. PMID:27853626

Indocyanine green SPY elite-assisted sentinel lymph node biopsy in cutaneous melanoma.

PubMed

Korn, Jason M; Tellez-Diaz, Alejandra; Bartz-Kurycki, Marisa; Gastman, Brian

2014-04-01

Sentinel lymph node biopsy is the standard of care for intermediate-depth and high-risk thin melanomas. Recently, indocyanine green and near-infrared imaging have been used to aid in sentinel node biopsy. The present study aimed to determine the feasibility of sentinel lymph node biopsy with indocyanine green SPY Elite navigation and to critically evaluate the technique compared with the standard modalities. A retrospective review of 90 consecutive cutaneous melanoma patients who underwent sentinel lymph node biopsy was performed. Two cohorts were formed: group A, which had sentinel lymph node biopsy performed with blue dye and radioisotope; and group B, which had sentinel lymph node biopsy performed with radioisotope and indocyanine green SPY Elite navigation. The cohorts were compared to assess for differences in localization rates, sensitivity and specificity of sentinel node identification, and length of surgery. The sentinel lymph node localization rate was 79.4 percent using the blue dye method, 98.0 percent using the indocyanine green fluorescence method, and 97.8 percent using the radioisotope/handheld gamma probe method. Indocyanine green fluorescence detected more sentinel lymph nodes than the vital dye method alone (p = 0.020). A trend toward a reduction in length of surgery was noted in the SPY Elite cohort. Sentinel lymph node mapping and localization in cutaneous melanoma with the indocyanine green SPY Elite navigation system is technically feasible and may offer several advantages over current modalities, including higher sensitivity and specificity, decreased number of lymph nodes sampled, decreased operative time, and potentially lower false-negative rates. Diagnostic, II.

Paired-agent fluorescent imaging to detect micrometastases in breast sentinel lymph node biopsy: experiment design and protocol development

NASA Astrophysics Data System (ADS)

Li, Chengyue; Xu, Xiaochun; Basheer, Yusairah; He, Yusheng; Sattar, Husain A.; Brankov, Jovan G.; Tichauer, Kenneth M.

2018-02-01

Sentinel lymph node status is a critical prognostic factor in breast cancer treatment and is essential to guide future adjuvant treatment. The estimation that 20-60% of micrometastases are missed by conventional pathology has created a demand for the development of more accurate approaches. Here, a paired-agent imaging approach is presented that employs a control imaging agent to allow rapid, quantitative mapping of microscopic populations of tumor cells in lymph nodes to guide pathology sectioning. To test the feasibility of this approach to identify micrometastases, healthy pig lymph nodes were stained with targeted and control imaging agent solution to evaluate the potential for the agents to diffuse into and out of intact nodes. Aby-029, an anti-EGFR affibody was labeled with IRDye 800CW (LICOR) as targeted agent and IRDye 700DX was hydrolyzed as a control agent. Lymph nodes were stained and rinsed by directly injecting the agents into the lymph nodes after immobilization in agarose gel. Subsequently, lymph nodes were frozen-sectioned and imaged under an 80-um resolution fluorescence imaging system (Pearl, LICOR) to confirm equivalence of spatial distribution of both agents in the entire node. The binding potentials were acquired by a pixel-by-pixel calculation and was found to be 0.02 +/- 0.06 along the lymph node in the absence of binding. The results demonstrate this approach's potential to enhance the sensitivity of lymph node pathology by detecting fewer than 1000 cell in a whole human lymph node.

Development and biodistribution of a theranostic aluminum phthalocyanine nanophotosensitizer.

PubMed

Asem, Heba; El-Fattah, Ahmed Abd; Nafee, Noha; Zhao, Ying; Khalil, Labiba; Muhammed, Mamoun; Hassan, Moustapha; Kandil, Sherif

2016-03-01

Aluminum phthalocyanine (AlPc) is an efficient second generation photosensitizer (PS) with high fluorescence ability. Its use in photodynamic therapy (PDT) is hampered by hydrophobicity and poor biodistribution. AlPc was converted to a biocompatible nanostructure by incorporation into amphiphilic polyethylene glycol-polycaprolactone (PECL) copolymer nanoparticles, allowing efficient entrapment of the PS in the hydrophobic core, water dispersibility and biodistribution enhancement by PEG-induced surface characteristics. A series of synthesized PECL copolymers were used to prepare nanophotosensitizers with an average diameter of 66.5-99.1nm and encapsulation efficiency (EE%) of 66.4-78.0%. One formulation with favorable colloidal properties and relatively slow release over 7 days was selected for in vitro photophysical assessment and in vivo biodistribution studies in mice. The photophysical properties of AlPc were improved by encapsulating AlPc into PECL-NPs, which showed intense fluorescence emission at 687nm and no AlPc aggregation has been induced after entrapment into the nanoparticles. Biodistribution of AlPc loaded NPs (AlPc-NPs) and free AlPc drug in mice was monitored by in vivo whole body fluorescence imaging and ex vivo organ imaging, with in vivo imaging system (IVIS). Compared to a AlPc solution in aqueous TWEEN 80 (2 w/v%), the developed nanophotosensitizer showed targeted drug delivery to lungs, liver and spleen as monitored by the intrinsic fluorescence of AlPc at different time points (1h, 24h and 48h) post iv. administration. The AlPc-based copolymer nanoparticles developed offer potential as a single agent-multifunctional theranostic nanophotosensitizer for PDT coupled with imaging-guided drug delivery and biodistribution, and possibly also fluorescence diagnostics. Copyright © 2015 Elsevier B.V. All rights reserved.

Developing Causal Understanding with Causal Maps: The Impact of Total Links, Temporal Flow, and Lateral Position of Outcome Nodes

ERIC Educational Resources Information Center

Jeong, Allan; Lee, Woon Jee

2012-01-01

This study examined some of the methodological approaches used by students to construct causal maps in order to determine which approaches help students understand the underlying causes and causal mechanisms in a complex system. This study tested the relationship between causal understanding (ratio of root causes correctly/incorrectly identified,…

A Scalable Heuristic for Viral Marketing Under the Tipping Model

DTIC Science & Technology

2013-09-01

removal of high-degree nodes. The rest of the paper is organized as follows. In Section 2, we provide formal definitions of the tipping model. This is...that must be activated for it to become activate as well. A Scalable Heuristic for Viral Marketing Under the Tipping Model 3 Definition 1 (Threshold...returns a set of active nodes after one time step. Definition 2 (Activation Function) Given a threshold function, θ, an ac- tivation function Aθ maps

Impact of Tumor Localization and Method of Preoperative Biopsy on Sentinel Lymph Node Mapping After Periareolar Nuclide Injection.

PubMed

Krammer, Julia; Dutschke, Anja; Kaiser, Clemens G; Schnitzer, Andreas; Gerhardt, Axel; Radosa, Julia C; Brade, Joachim; Schoenberg, Stefan O; Wasser, Klaus

2016-01-01

To evaluate whether tumor localization and method of preoperative biopsy affect sentinel lymph node (SLN) detection after periareolar nuclide injection in breast cancer patients. 767 breast cancer patients were retrospectively included. For lymphscintigraphy periareolar nuclide injection was performed and the SLN was located by gamma camera. Patient and tumor characteristics were correlated to the success rate of SLN mapping. SLN marking failed in 9/61 (14.7%) patients with prior vacuum-assisted biopsy and 80/706 (11.3%) patients with prior core needle biopsy. Individually evaluated, biopsy method (p = 0.4) and tumor localization (p = 0.9) did not significantly affect the SLN detection rate. Patients with a vacuum-assisted biopsy of a tumor in the upper outer quadrant had a higher odds ratio of failing in SLN mapping (OR 3.8, p = 0.09) compared to core needle biopsy in the same localization (OR 0.9, p = 0.5). Tumor localization and preoperative biopsy method do not significantly impact SLN mapping with periareolar nuclide injection. However, the failure risk tends to rise if vacuum-assisted biopsy of a tumor in the upper outer quadrant is performed.

Highly enhanced optical properties of indocyanine green/perfluorocarbon nanoemulsions for efficient lymph node mapping using near-infrared and magnetic resonance imaging

NASA Astrophysics Data System (ADS)

Bae, Pan Kee; Jung, Juyeon; Chung, Bong Hyun

2014-03-01

The near-infrared (NIR) fluorescence probe has better tissue penetration and lower autofluorescence. Indocyanine green (ICG) is an NIR organic dye for extensive biological application, and it has been clinically approved for human medical imaging and diagnosis. However, application of this dye is limited by its numerous disadvantageous properties in aqueous solution, including its concentration-dependent aggregation, poor aqueous stability in vitro, and low quantum yield. Its use in molecular imaging probes is limited because it loses fluorescence after binding to nonspecific plasma proteins, leading to rapid elimination from the body with a half-life of 2 - 4 min. In this study, the multifunctional perfluorocarbon (PFC)/ICG nanoemulsions were investigated with the aim of overcoming these limitations. The PFC/ICG nanoemulsions as a new type of delivery vehicle for contrast agents have both NIR optical imaging and 19 F-MR imaging moieties. These nanoemulsions exhibited less aggregation, increased fluorescence intensity, long-term stability, and physicochemical stability against external light and temperature compared to free aqueous ICG. Also, the PFC/ICG bimodal nanoemulsions allow excellent detection of lymph nodes in vivo through NIR optical imaging and 19 F-MR imaging. This result showed the suitability of the proposed nanoemulsions for non-invasive lymph node mapping as they enable long-time detection of lymph nodes.

Coherent exciton transport in dendrimers and continuous-time quantum walks

NASA Astrophysics Data System (ADS)

Mülken, Oliver; Bierbaum, Veronika; Blumen, Alexander

2006-03-01

We model coherent exciton transport in dendrimers by continuous-time quantum walks. For dendrimers up to the second generation the coherent transport shows perfect recurrences when the initial excitation starts at the central node. For larger dendrimers, the recurrence ceases to be perfect, a fact which resembles results for discrete quantum carpets. Moreover, depending on the initial excitation site, we find that the coherent transport to certain nodes of the dendrimer has a very low probability. When the initial excitation starts from the central node, the problem can be mapped onto a line which simplifies the computational effort. Furthermore, the long time average of the quantum mechanical transition probabilities between pairs of nodes shows characteristic patterns and allows us to classify the nodes into clusters with identical limiting probabilities. For the (space) average of the quantum mechanical probability to be still or to be again at the initial site, we obtain, based on the Cauchy-Schwarz inequality, a simple lower bound which depends only on the eigenvalue spectrum of the Hamiltonian.

Embedding global barrier and collective in torus network with each node combining input from receivers according to class map for output to senders

DOEpatents

Chen, Dong; Coteus, Paul W; Eisley, Noel A; Gara, Alan; Heidelberger, Philip; Senger, Robert M; Salapura, Valentina; Steinmacher-Burow, Burkhard; Sugawara, Yutaka; Takken, Todd E

2013-08-27

Embodiments of the invention provide a method, system and computer program product for embedding a global barrier and global interrupt network in a parallel computer system organized as a torus network. The computer system includes a multitude of nodes. In one embodiment, the method comprises taking inputs from a set of receivers of the nodes, dividing the inputs from the receivers into a plurality of classes, combining the inputs of each of the classes to obtain a result, and sending said result to a set of senders of the nodes. Embodiments of the invention provide a method, system and computer program product for embedding a collective network in a parallel computer system organized as a torus network. In one embodiment, the method comprises adding to a torus network a central collective logic to route messages among at least a group of nodes in a tree structure.

Optimal Deployment of Sensor Nodes Based on Performance Surface of Underwater Acoustic Communication

PubMed Central

Choi, Jee Woong

2017-01-01

The underwater acoustic sensor network (UWASN) is a system that exchanges data between numerous sensor nodes deployed in the sea. The UWASN uses an underwater acoustic communication technique to exchange data. Therefore, it is important to design a robust system that will function even in severely fluctuating underwater communication conditions, along with variations in the ocean environment. In this paper, a new algorithm to find the optimal deployment positions of underwater sensor nodes is proposed. The algorithm uses the communication performance surface, which is a map showing the underwater acoustic communication performance of a targeted area. A virtual force-particle swarm optimization algorithm is then used as an optimization technique to find the optimal deployment positions of the sensor nodes, using the performance surface information to estimate the communication radii of the sensor nodes in each generation. The algorithm is evaluated by comparing simulation results between two different seasons (summer and winter) for an area located off the eastern coast of Korea as the selected targeted area. PMID:29053569

Normal distribution pattern and physiological variants of 68Ga-PSMA-11 PET/CT imaging.

PubMed

Demirci, Emre; Sahin, Onur Erdem; Ocak, Meltem; Akovali, Burak; Nematyazar, Jamal; Kabasakal, Levent

2016-11-01

Ga-PSMA-11 is a novel PET tracer suggested to be used for imaging of advanced prostate cancer. In this study, we aimed to present a detailed biodistribution of Ga-PSMA-11, including physiological and benign variants of prostate-specific membrane antigen (PSMA) imaging. We carried out a retrospective analysis of 40 patients who underwent PSMA PET/computed tomography (CT) imaging and who had no evidence of residual or metastatic disease on the scans. In addition, 16 patients who underwent PSMA PET/CT imaging with any indication other than prostate cancer were included in the study to evaluate physiological uptake in the normal prostate gland. The median, minimum-maximum, and mean standardized uptake value (SUV) values were calculated for visceral organs, bone marrow and lymph nodes, and mucosal areas. Any physiological variants or benign lesions with Ga-PSMA-11 were also noted. Ga-PSMA-11 uptake was noted in the kidneys, parotid and submandibular glands, duodenum, small intestines, spleen, liver, and lacrimal glands, and mucosal uptake in the nasopharynx, vocal cords, pancreas, stomach, mediastinal blood pool, thyroid gland, adrenal gland, rectum, vertebral bone marrow, and testes. Celiac ganglia showed slight Ga-PSMA-11 uptake in 24 of 40 patients without the presence of any other pathologic lymph nodes in abdominal and pelvic areas. Variable uptake of Ga-PSMA-11 was observed in calcified choroid plexus, a thyroid nodule, an adrenal nodule, axillary lymph nodes and celiac ganglia, occasional osteophytes, and gallbladder. The patient group with PSMA PET/CT for indications other than prostate cancer (n=16) showed a slight radiotracer uptake in normal prostate gland (SUVmax: 5.5±1.6, range: 3.5-8.3). This study shows normal distribution pattern, range of SUVs, and physiological variants of Ga-PSMA-11. In addition, several potential pitfalls were documented to prevent misinterpretations of the scan.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soerensen, M.P.; Davidson, A.; Pedersen, N.F.

We use the method of cell-to-cell mapping to locate attractors, basins, and saddle nodes in the phase plane of a driven Josephson junction. The cell-mapping method is discussed in some detail, emphasizing its ability to provide a global view of the phase plane. Our computations confirm the existence of a previously reported interior crisis. In addition, we observe a boundary crisis for a small shift in one parameter. The cell-mapping method allows us to show both crises explicitly in the phase plane, at low computational cost.

Biodistribution and PET Imaging of pharmacokinetics of manganese in mice using Manganese-52

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wooten, A. Lake; Aweda, Tolulope A.; Lewis, Benjamin C.

Manganese is essential to life, and humans typically absorb sufficient quantities of this element from a normal healthy diet; however, chronic, elevated ingestion or inhalation of manganese can be neurotoxic, potentially leading to manganism. Although imaging of large amounts of accumulated Mn(II) is possible by MRI, quantitative measurement of the biodistribution of manganese, particularly at the trace level, can be challenging. In this study, we produced the positron-emitting radionuclide 52Mn (t 1/2 = 5.6 d) by proton bombardment (E p<15 MeV) of chromium metal, followed by solid-phase isolation by cation-exchange chromatography. An aqueous solution of [ 52Mn]MnCl 2 was nebulizedmore » into a closed chamber with openings through which mice inhaled the aerosol, and a separate cohort of mice received intravenous (IV) injections of [ 52Mn]MnCl 2. Ex vivo biodistribution was performed at 1 h and 1 d post-injection/inhalation (p.i.). In both trials, we observed uptake in lungs and thyroid at 1 d p.i. Manganese is known to cross the blood-brain barrier, as confirmed in our studies following IV injection (0.86%ID/g, 1 d p.i.) and following inhalation of aerosol, (0.31%ID/g, 1 d p.i.). Uptake in salivary gland and pancreas were observed at 1 d p.i. (0.5 and 0.8%ID/g), but to a much greater degree from IV injection (6.8 and 10%ID/g). In a separate study, mice received IV injection of an imaging dose of [ 52Mn]MnCl 2, followed by in vivo imaging by positron emission tomography (PET) and ex vivo biodistribution. The results from this study supported many of the results from the biodistribution-only studies. In this work, we have confirmed results in the literature and contributed new results for the biodistribution of inhaled radiomanganese for several organs. In conclusion, our results could serve as supporting information for environmental and occupational regulations, for designing PET studies utilizing 52Mn, and/or for predicting the biodistribution of manganese-based MR contrast agents.« less

Effects of hyperglycemia on fluorine-18-fluorodeoxyglucose biodistribution in a large oncology clinical practice.

PubMed

Rosica, Dillenia; Cheng, Su-Chun; Hudson, Margo; Sakellis, Christopher; Van den Abbeele, Annick D; Kim, Chun K; Jacene, Heather A

2018-05-01

Suggested cutoff points of blood glucose levels (BGL) before F-FDG PET/CT scanning vary between 120 and 200 mg/dl in current guidelines. This study's purpose was to compare the frequency of abnormal fluorine-18-fluorodeoxyglucose (F-FDG) biodistribution on PET/CT scans of patients with various ranges of abnormal BGL and to determine the effect of BGL greater than 200 mg/dl on F-FDG uptake in various organs. F-FDG PET/CT scans were retrospectively reviewed for 325 patients with BGL greater than 120 mg/dl at the time of scan and 112 with BGL less than or equal to 120 mg/dl. F-FDG biodistribution was categorized as normal, mildly abnormal, or abnormal by visual analysis of brain, background soft tissue, and muscle. Mean standardized uptake values (SUVmean) in brain, liver, fat (flank), gluteal muscle, and blood pool (aorta) were recorded. F-FDG biodistribution frequencies were assessed using a nonparametric χ-test for trend. Normal organ SUVs were compared using Kruskal-Wallis tests using the following BGL groupings: ≤120, 121-150, 151-200, and ≥201 mg/dl. Although higher BGL were significantly associated with an increased proportion of abnormal biodistribution (P<0.001), most patients with BGL less than or equal to 200 mg/dl had normal or mildly abnormal biodistribution. Average brain SUVmean significantly decreased with higher BGL groupings (P<0.001). Average aorta, gluteal muscle, and liver SUVmean did not significantly differ among groups with BGL greater than 120 mg/dl (P=0.66, 0.84, and 0.39, respectively), but were significantly lower in those with BGL less than or equal to 120 mg/dl (P≤0.001). Flank fat SUVmean was not significantly different among BGL groups (P=0.67). Abnormal F-FDG biodistribution is associated with higher BGL at the time of scan, but the effects are negligible or mild in most patients with BGL less than 200 mg/dl. Although mildly increased soft tissue uptake is seen with BGL greater than 120 mg/dl, decline in brain metabolic activity correlated the most with various BGL.

Comprehensive characterizations of nanoparticle biodistribution following systemic injection in mice

NASA Astrophysics Data System (ADS)

Liao, Wei-Yin; Li, Hui-Jing; Chang, Ming-Yao; Tang, Alan C. L.; Hoffman, Allan S.; Hsieh, Patrick C. H.

2013-10-01

Various nanoparticle (NP) properties such as shape and surface charge have been studied in an attempt to enhance the efficacy of NPs in biomedical applications. When trying to undermine the precise biodistribution of NPs within the target organs, the analytical method becomes the determining factor in measuring the precise quantity of distributed NPs. High performance liquid chromatography (HPLC) represents a more powerful tool in quantifying NP biodistribution compared to conventional analytical methods such as an in vivo imaging system (IVIS). This, in part, is due to better curve linearity offered by HPLC than IVIS. Furthermore, HPLC enables us to fully analyze each gram of NPs present in the organs without compromising the signals and the depth-related sensitivity as is the case in IVIS measurements. In addition, we found that changing physiological conditions improved large NP (200-500 nm) distribution in brain tissue. These results reveal the importance of selecting analytic tools and physiological environment when characterizing NP biodistribution for future nanoscale toxicology, therapeutics and diagnostics.Various nanoparticle (NP) properties such as shape and surface charge have been studied in an attempt to enhance the efficacy of NPs in biomedical applications. When trying to undermine the precise biodistribution of NPs within the target organs, the analytical method becomes the determining factor in measuring the precise quantity of distributed NPs. High performance liquid chromatography (HPLC) represents a more powerful tool in quantifying NP biodistribution compared to conventional analytical methods such as an in vivo imaging system (IVIS). This, in part, is due to better curve linearity offered by HPLC than IVIS. Furthermore, HPLC enables us to fully analyze each gram of NPs present in the organs without compromising the signals and the depth-related sensitivity as is the case in IVIS measurements. In addition, we found that changing physiological conditions improved large NP (200-500 nm) distribution in brain tissue. These results reveal the importance of selecting analytic tools and physiological environment when characterizing NP biodistribution for future nanoscale toxicology, therapeutics and diagnostics. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr03954d

Biodistribution and PET Imaging of pharmacokinetics of manganese in mice using Manganese-52

DOE PAGES

Wooten, A. Lake; Aweda, Tolulope A.; Lewis, Benjamin C.; ...

2017-03-17

Manganese is essential to life, and humans typically absorb sufficient quantities of this element from a normal healthy diet; however, chronic, elevated ingestion or inhalation of manganese can be neurotoxic, potentially leading to manganism. Although imaging of large amounts of accumulated Mn(II) is possible by MRI, quantitative measurement of the biodistribution of manganese, particularly at the trace level, can be challenging. In this study, we produced the positron-emitting radionuclide 52Mn (t 1/2 = 5.6 d) by proton bombardment (E p<15 MeV) of chromium metal, followed by solid-phase isolation by cation-exchange chromatography. An aqueous solution of [ 52Mn]MnCl 2 was nebulizedmore » into a closed chamber with openings through which mice inhaled the aerosol, and a separate cohort of mice received intravenous (IV) injections of [ 52Mn]MnCl 2. Ex vivo biodistribution was performed at 1 h and 1 d post-injection/inhalation (p.i.). In both trials, we observed uptake in lungs and thyroid at 1 d p.i. Manganese is known to cross the blood-brain barrier, as confirmed in our studies following IV injection (0.86%ID/g, 1 d p.i.) and following inhalation of aerosol, (0.31%ID/g, 1 d p.i.). Uptake in salivary gland and pancreas were observed at 1 d p.i. (0.5 and 0.8%ID/g), but to a much greater degree from IV injection (6.8 and 10%ID/g). In a separate study, mice received IV injection of an imaging dose of [ 52Mn]MnCl 2, followed by in vivo imaging by positron emission tomography (PET) and ex vivo biodistribution. The results from this study supported many of the results from the biodistribution-only studies. In this work, we have confirmed results in the literature and contributed new results for the biodistribution of inhaled radiomanganese for several organs. In conclusion, our results could serve as supporting information for environmental and occupational regulations, for designing PET studies utilizing 52Mn, and/or for predicting the biodistribution of manganese-based MR contrast agents.« less

Evaluation of N-[(11)C]methyl-AMD3465 as a PET tracer for imaging of CXCR4 receptor expression in a C6 glioma tumor model.

PubMed

Hartimath, S V; van Waarde, A; Dierckx, R A J O; de Vries, E F J

2014-11-03

The chemokine receptor CXCR4 and its ligand CXCL12 play an important role in tumor progression and metastasis. CXCR4 receptors are expressed by many cancer types and provide a potential target for treatment. Noninvasive detection of CXCR4 may aid diagnosis and improve therapy selection. It has been demonstrated in preclinical studies that positron emission tomography (PET) with a radiolabeled small molecule could enable noninvasive monitoring of CXCR4 expression. Here, we prepared N-[(11)C]methyl-AMD3465 as a new PET tracer for CXCR4. N-[(11)C]Methyl-AMD3465 was readily prepared by N-methylation with [(11)C]CH3OTf. The tracer was obtained in a 60 ± 2% yield (decay corrected), the purity of the tracer was >99%, and specific activity was 47 ± 14 GBq/μmol. Tracer stability was tested in vitro using liver microsomes and rat plasma; excellent stability was observed. The tracer was evaluated in rat C6 glioma and human PC-3 cell lines. In vitro cellular uptake of N-[(11)C]methyl-AMD3465 was receptor mediated. The effect of transition metal ions (Cu(2+), Ni(2+), and Zn(2+)) on cellular binding was examined in C6 cells, and the presence of these ions increased the cellular binding of the tracer 9-, 7-, and 3-fold, respectively. Ex vivo biodistribution and PET imaging of N-[(11)C]methyl-AMD3465 were performed in rats with C6 tumor xenografts. Both PET and biodistribution studies demonstrated specific accumulation of the tracer in the tumor (SUV 0.6 ± 0.2) and other CXCR4 expressing organs, such as lymph node (1.5 ± 0.2), liver (8.9 ± 1.0), bone marrow (1.0 ± 0.3), and spleen (1.0 ± 0.1). Tumor uptake was significantly reduced (66%, p < 0.01) after pretreatment with Plerixafor (AMD3100). Biodistribution data indicates a tumor-to-muscle ratio of 7.85 and tumor-to-plasma ratio of 1.14, at 60 min after tracer injection. Our data demonstrated that N-[(11)C]methyl-AMD3465 is capable of detecting physiologic CXCR4 expression in tumors and other CXCR4 expressing tissues. These results warrant further evaluation of N-[(11)C]methyl-AMD3465 as a potential PET tracer for CXCR4 receptor imaging.

Efficacy of Sentinel Lymph Node Biopsy in Detecting Axillary Metastasis in Breast Cancer Using Methylene Blue.

PubMed

Nandu, Vipul V; Chaudhari, Milind S

2017-06-01

Breast cancer is the leading malignancy and the second leading cause of cancer-related deaths. Axillary lymph node status is a very important prognostic factor in breast cancer patients; nodal evaluation is therefore a critical part of breast cancer management. Axillary lymph node dissection results in significant morbidity. Sentinel lymph node biopsy (SLNB) is being used in many centers to stage the axilla in planning axillary dissection management of patients and hence plays an important part in reducing morbidity among patients with carcinoma breast. The objectives of this paper is to study the (1) efficacy of sentinel lymph node biopsy in detecting axillary metastasis, (2) location of sentinel lymph node in the axilla, (3) rate of involvement of sentinel lymph nodes, and (4) incidence of skip metastasis. Thirty-five patients with breast cancer with clinically node-negative axilla were selected for the study. Methylene blue dye was injected intralesional and perilesional 20 min prior to surgery. All patients underwent modified radical mastectomy with sentinel lymph node biopsy and axillary dissection and after pathological examination diagnostic statics, namely sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were computed. Sentinel lymph node was identified in all of these patients. Sixty percent patients had pathologically positive lymph nodes in the axilla. 90.48% patients of these had sentinel lymph nodes positive for malignant cells. Incidence of skip metastasis is 9.52%. 88.57% patients had sentinel lymph node mapped to level I lymph nodes. Sensitivity of SLNB is 90.48%, specificity is 85.71%, PPV of is 90.48%, NPV is 85.71%, and accuracy is 88.57%. Sentinel lymph node biopsy is an effective method of staging the axilla and deciding on axillary clearance in patients of carcinoma breast. Unnecessary axillary dissection and associated complications can be prevented in most of patients due to sentinel lymph node biopsy.

Energy-efficient virtual optical network mapping approaches over converged flexible bandwidth optical networks and data centers.

PubMed

Chen, Bowen; Zhao, Yongli; Zhang, Jie

2015-09-21

In this paper, we develop a virtual link priority mapping (LPM) approach and a virtual node priority mapping (NPM) approach to improve the energy efficiency and to reduce the spectrum usage over the converged flexible bandwidth optical networks and data centers. For comparison, the lower bound of the virtual optical network mapping is used for the benchmark solutions. Simulation results show that the LPM approach achieves the better performance in terms of power consumption, energy efficiency, spectrum usage, and the number of regenerators compared to the NPM approach.

Graph Unification and Tangram Hypothesis Explanation Representation (GATHER) and System and Component Modeling Framework (SCMF)

DTIC Science & Technology

2008-08-01

services, DIDS and DMS, are deployable on the TanGrid system and are accessible via two APIs, a Java client and a servlet based interface. Additionally...but required the user to instantiate an IGraph object with several Java Maps containing the nodes, node attributes, edge types, and the connections...restrictions imposed by the bulk ingest process. Finally, once the bulk ingest process was available in the GraphUnification Java Archives (JAR), DC was

A privacy-preserving parallel and homomorphic encryption scheme

NASA Astrophysics Data System (ADS)

Min, Zhaoe; Yang, Geng; Shi, Jingqi

2017-04-01

In order to protect data privacy whilst allowing efficient access to data in multi-nodes cloud environments, a parallel homomorphic encryption (PHE) scheme is proposed based on the additive homomorphism of the Paillier encryption algorithm. In this paper we propose a PHE algorithm, in which plaintext is divided into several blocks and blocks are encrypted with a parallel mode. Experiment results demonstrate that the encryption algorithm can reach a speed-up ratio at about 7.1 in the MapReduce environment with 16 cores and 4 nodes.

A Combined HIPPARCOS and Multichannel Astrometric Photometer Study of the Proposed Planetary System of Rho Coronae Borealis

NASA Technical Reports Server (NTRS)

Gatewood, George; Han, Inwoo; Black, David C.

2001-01-01

Hipparcos and Multichannel Astrometric Photometer (MAP) observations of rho Coronae Borealis independently display astrometric motion at the period of the proposed extrasolar planetary companion to the star. Individual least-squares fits to each astrometric data set yield independent estimates of the semimajor axis, inclination, and node angle that are in excellent agreement. A combined solution of the Hipparcos and MAP data yields an inclination of 0.5 deg, a node at 30.5 +/- 12.4, and a semimajor axis of 1.66 +/- 0.35 mas, indicating a companion mass of 0.14 +/- 0.05 solar masses over two orders of magnitude greater than the minimum mass for the companion as determined by radial velocity studies. This mass is approximately that of an M dwarf star, the companion cannot be a planetary object.

Corticocortical evoked potentials reveal projectors and integrators in human brain networks.

PubMed

Keller, Corey J; Honey, Christopher J; Entz, Laszlo; Bickel, Stephan; Groppe, David M; Toth, Emilia; Ulbert, Istvan; Lado, Fred A; Mehta, Ashesh D

2014-07-02

The cerebral cortex is composed of subregions whose functional specialization is largely determined by their incoming and outgoing connections with each other. In the present study, we asked which cortical regions can exert the greatest influence over other regions and the cortical network as a whole. Previous research on this question has relied on coarse anatomy (mapping large fiber pathways) or functional connectivity (mapping inter-regional statistical dependencies in ongoing activity). Here we combined direct electrical stimulation with recordings from the cortical surface to provide a novel insight into directed, inter-regional influence within the cerebral cortex of awake humans. These networks of directed interaction were reproducible across strength thresholds and across subjects. Directed network properties included (1) a decrease in the reciprocity of connections with distance; (2) major projector nodes (sources of influence) were found in peri-Rolandic cortex and posterior, basal and polar regions of the temporal lobe; and (3) major receiver nodes (receivers of influence) were found in anterolateral frontal, superior parietal, and superior temporal regions. Connectivity maps derived from electrical stimulation and from resting electrocorticography (ECoG) correlations showed similar spatial distributions for the same source node. However, higher-level network topology analysis revealed differences between electrical stimulation and ECoG that were partially related to the reciprocity of connections. Together, these findings inform our understanding of large-scale corticocortical influence as well as the interpretation of functional connectivity networks. Copyright © 2014 the authors 0270-6474/14/349152-12$15.00/0.

Embedding global and collective in a torus network with message class map based tree path selection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Dong; Coteus, Paul W.; Eisley, Noel A.

Embodiments of the invention provide a method, system and computer program product for embedding a global barrier and global interrupt network in a parallel computer system organized as a torus network. The computer system includes a multitude of nodes. In one embodiment, the method comprises taking inputs from a set of receivers of the nodes, dividing the inputs from the receivers into a plurality of classes, combining the inputs of each of the classes to obtain a result, and sending said result to a set of senders of the nodes. Embodiments of the invention provide a method, system and computermore » program product for embedding a collective network in a parallel computer system organized as a torus network. In one embodiment, the method comprises adding to a torus network a central collective logic to route messages among at least a group of nodes in a tree structure.« less

Lymph Node Assessment in Endometrial Cancer: Towards Personalized Medicine

PubMed Central

Vidal, Fabien; Rafii, Arash

2013-01-01

Endometrial cancer (EC) is the most common malignancy of the female reproductive tract and is increasing in incidence. Lymphovascular invasion and lymph node (LN) status are strong predictive factors of recurrence. Therefore, the determination of the nodal status of patients is mandatory to optimally tailor adjuvant therapies and reduce local and distant recurrences. Imaging modalities do not yet allow accurate lymph node staging; thus pelvic and aortic lymphadenectomies remain standard staging procedures. The clinical data accumulated recently allow us to define low- and high-risk patients based on pre- or peroperative findings that will allow the clinician to stratify the patients for their need of lymphadenectomies. More recently, several groups have been introducing sentinel node mapping with promising results as an alternative to complete lymphadenectomy. Finally, the use of peroperative algorithm for risk determination could improve patient's staging with a reduction of lymphadenectomy-related morbidity. PMID:24191159

Automatic Earth observation data service based on reusable geo-processing workflow

NASA Astrophysics Data System (ADS)

Chen, Nengcheng; Di, Liping; Gong, Jianya; Yu, Genong; Min, Min

2008-12-01

A common Sensor Web data service framework for Geo-Processing Workflow (GPW) is presented as part of the NASA Sensor Web project. This framework consists of a data service node, a data processing node, a data presentation node, a Catalogue Service node and BPEL engine. An abstract model designer is used to design the top level GPW model, model instantiation service is used to generate the concrete BPEL, and the BPEL execution engine is adopted. The framework is used to generate several kinds of data: raw data from live sensors, coverage or feature data, geospatial products, or sensor maps. A scenario for an EO-1 Sensor Web data service for fire classification is used to test the feasibility of the proposed framework. The execution time and influences of the service framework are evaluated. The experiments show that this framework can improve the quality of services for sensor data retrieval and processing.

Universal ventricular coordinates: A generic framework for describing position within the heart and transferring data.

PubMed

Bayer, Jason; Prassl, Anton J; Pashaei, Ali; Gomez, Juan F; Frontera, Antonio; Neic, Aurel; Plank, Gernot; Vigmond, Edward J

2018-04-01

Being able to map a particular set of cardiac ventricles to a generic topologically equivalent representation has many applications, including facilitating comparison of different hearts, as well as mapping quantities and structures of interest between them. In this paper we describe Universal Ventricular Coordinates (UVC), which can be used to describe position within any biventricular heart. UVC comprise four unique coordinates that we have chosen to be intuitive, well defined, and relevant for physiological descriptions. We describe how to determine these coordinates for any volumetric mesh by illustrating how to properly assign boundary conditions and utilize solutions to Laplace's equation. Using UVC, we transferred scalar, vector, and tensor data between four unstructured ventricular meshes from three different species. Performing the mappings was very fast, on the order of a few minutes, since mesh nodes were searched in a KD tree. Distance errors in mapping mesh nodes back and forth between meshes were less than the size of an element. Analytically derived fiber directions were also mapped across meshes and compared, showing  < 5° difference over most of the ventricles. The ability to transfer gradients was also demonstrated. Topologically variable structures, like papillary muscles, required further definition outside of the UVC framework. In conclusion, UVC can aid in transferring many types of data between different biventricular geometries. Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.

Quantitative methods of identifying the key nodes in the illegal wildlife trade network

PubMed Central

Patel, Nikkita Gunvant; Rorres, Chris; Joly, Damien O.; Brownstein, John S.; Boston, Ray; Levy, Michael Z.; Smith, Gary

2015-01-01

Innovative approaches are needed to combat the illegal trade in wildlife. Here, we used network analysis and a new database, HealthMap Wildlife Trade, to identify the key nodes (countries) that support the illegal wildlife trade. We identified key exporters and importers from the number of shipments a country sent and received and from the number of connections a country had to other countries over a given time period. We used flow betweenness centrality measurements to identify key intermediary countries. We found the set of nodes whose removal from the network would cause the maximum disruption to the network. Selecting six nodes would fragment 89.5% of the network for elephants, 92.3% for rhinoceros, and 98.1% for tigers. We then found sets of nodes that would best disseminate an educational message via direct connections through the network. We would need to select 18 nodes to reach 100% of the elephant trade network, 16 nodes for rhinoceros, and 10 for tigers. Although the choice of locations for interventions should be customized for the animal and the goal of the intervention, China was the most frequently selected country for network fragmentation and information dissemination. Identification of key countries will help strategize illegal wildlife trade interventions. PMID:26080413

Repeat sentinel lymph node biopsy in patients with ipsilateral recurrent breast cancer after breast-conserving therapy and negative sentinel lymph node biopsy: a prospective study.

PubMed

Folli, Secondo; Falco, Giuseppe; Mingozzi, Matteo; Buggi, Federico; Curcio, Annalisa; Ferrari, Guglielmo; Taffurelli, Mario; Regolo, Lea; Nanni, Oriana

2016-04-01

Patients with ipsilateral breast tumor recurrence or new ipsilateral primary tumor after previous breast conservative surgery with negative sentinel lymph node biopsy need a new axillary staging procedure. However, the best surgical option, i.e. repeat sentinel lymph node biopsy or axillary lymph node dissection, is still debated. Purpose of the study is to assess the performance of repeat sentinel lymph node biopsy. In a multicenter study, lymph node biopsy completed by back-up axillary lymph node dissection was undertaken for ipsilateral breast tumor recurrence or new ipsilateral primary tumor. Tracer uptake was used to identify and isolate the sentinel lymph node during surgery, and it was classified after staining with hematoxylin and eosin and monoclonal anti-cytokeratin antibodies. Aside from negative predictive value, overall accuracy and false-negative rate of repeat sentinel lymph node biopsy were assessed. A multicenter, prospective study was conducted performing 30 repeat sentinel lymph node biopsy completed by back-up axillary lymph node dissection for ipsilateral breast tumor recurrence or new ipsilateral primary tumor in patients formerly treated with previous breast conservative surgery and negative sentinel lymph node biopsy. Negative predictive value, overall accuracy and false-negative rate of repeat sentinel lymph node biopsy were assessed. Sentinel lymph nodes were mapped in 27 patients out of 30 (90%). Aberrant drainage pathways were observed in one patient (3.7%). Tracer uptake was sufficient to identify and isolate the sentinel lymph node during surgery in 23 cases (76.6%); the patients in whom lymphoscintigraphy failed or no sentinel lymph nodes could be isolated underwent axillary lymph node dissection. The negative predictive value was 95.2%, the accuracy was 95.6% and the false-negative rate was 33%. Repeat sentinel lymph node biopsy is feasible and accurate, with a high negative predictive value. Patients with ipsilateral breast tumor recurrence or new ipsilateral primary tumor after previous breast conservative surgery and negative sentinel lymph node biopsy can be treated with repeat sentinel lymph node biopsy for the axillary staging and can be spared axillary dissection in case of absence of metastases. However, repeat sentinel lymph node biopsy may prove technically impracticable in about one quarter of cases and thus axillary lymph node dissection remains the only viable option in such instance.

Sentinel lymph node detection in early cervical cancer with combination 99mTc phytate and patent blue.

PubMed

Niikura, Hitoshi; Okamura, Chikako; Akahira, Junichi; Takano, Tadao; Ito, Kiyoshi; Okamura, Kunihiro; Yaegashi, Nobuo

2004-08-01

The purpose of this study was to examine sentinel lymph node (SLN) detection in patients with early stage cervical cancer using (99m)Tc phytate and patent blue dye and to compare our method with published findings utilizing other radioisotopic tracers. A total of 20 consecutive patients with cervical cancer scheduled for radical hysterectomy and total pelvic lymphadenectomy at our hospital underwent SLN detection study. The day before surgery, lymphoscintigraphy was performed with injection of 99m-technetium ((99m)Tc)-labeled phytate into the uterine cervix. At surgery, patients underwent lymphatic mapping with a gamma-detecting probe and patent blue injected into the same points as the phytate solution. At least one positive node was detected in 18 patients (90%). A total of 46 sentinel nodes were detected (mean, 2.3; range, 1-5). Most sentinel nodes were in one of the following sites: external iliac (21 nodes), obturator (15 nodes), and parametrial (7 nodes). Eleven (24%) sentinel nodes were detected only through radioactivity and two (4%) were detected only with blue dye. The sensitivity, specificity, and negative predictive value for SLN detection were all 100%. Nine published studies involving 295 patients had a summarized detection rate of 85%. Summarized sensitivity, specificity, and negative predictive value were 93%, 100%, and 99%, respectively. Combination of (99m)Tc phytate and patent blue is effective in SLN detection in early stage cervical cancer.

Efficient feature extraction from wide-area motion imagery by MapReduce in Hadoop

NASA Astrophysics Data System (ADS)

Cheng, Erkang; Ma, Liya; Blaisse, Adam; Blasch, Erik; Sheaff, Carolyn; Chen, Genshe; Wu, Jie; Ling, Haibin

2014-06-01

Wide-Area Motion Imagery (WAMI) feature extraction is important for applications such as target tracking, traffic management and accident discovery. With the increasing amount of WAMI collections and feature extraction from the data, a scalable framework is needed to handle the large amount of information. Cloud computing is one of the approaches recently applied in large scale or big data. In this paper, MapReduce in Hadoop is investigated for large scale feature extraction tasks for WAMI. Specifically, a large dataset of WAMI images is divided into several splits. Each split has a small subset of WAMI images. The feature extractions of WAMI images in each split are distributed to slave nodes in the Hadoop system. Feature extraction of each image is performed individually in the assigned slave node. Finally, the feature extraction results are sent to the Hadoop File System (HDFS) to aggregate the feature information over the collected imagery. Experiments of feature extraction with and without MapReduce are conducted to illustrate the effectiveness of our proposed Cloud-Enabled WAMI Exploitation (CAWE) approach.

Preclinical Evaluation of Robotic-Assisted Sentinel Lymph Node Fluorescence Imaging

PubMed Central

Liss, Michael A.; Farshchi-Heydari, Salman; Qin, Zhengtao; Hickey, Sean A.; Hall, David J.; Kane, Christopher J.; Vera, David R.

2015-01-01

An ideal substance to provide convenient and accurate targeting for sentinel lymph node (SLN) mapping during robotic-assisted surgery has yet to be found. We used an animal model to determine the ability of the FireFly camera system to detect fluorescent SLNs after administration of a dual-labeled molecular imaging agent. Methods We injected the footpads of New Zealand White rabbits with 1.7 or 8.4 nmol of tilmanocept labeled with 99mTc and a near-infrared fluorophore, IRDye800CW. One and 36 h after injection, popliteal lymph nodes, representing the SLNs, were dissected with the assistance of the FireFly camera system, a fluorescence-capable endoscopic imaging system. After excision of the paraaortic lymph nodes, which represented non-SLNs, we assayed all lymph nodes for radioactivity and fluorescence intensity. Results Fluorescence within all popliteal lymph nodes was easily detected by the FireFly camera system. Fluorescence within the lymph channel could be imaged during the 1-h studies. When compared with the paraaortic lymph nodes, the popliteal lymph nodes retain greater than 95% of the radioactivity at both 1 and 36 h after injection. At both doses (1.7 and 8.4 nmol), the popliteal nodes had higher (P < 0.050) optical fluorescence intensity than the paraaortic nodes at the 1- and 36-h time points. Conclusion The FireFly camera system can easily detect tilmanocept labeled with a near-infrared fluorophore at least 36 h after administration. This ability will permit image acquisition and subsequent verification of fluorescence-labeled SLNs during robotic-assisted surgery. PMID:25024425

Preclinical evaluation of robotic-assisted sentinel lymph node fluorescence imaging.

PubMed

Liss, Michael A; Farshchi-Heydari, Salman; Qin, Zhengtao; Hickey, Sean A; Hall, David J; Kane, Christopher J; Vera, David R

2014-09-01

An ideal substance to provide convenient and accurate targeting for sentinel lymph node (SLN) mapping during robotic-assisted surgery has yet to be found. We used an animal model to determine the ability of the FireFly camera system to detect fluorescent SLNs after administration of a dual-labeled molecular imaging agent. We injected the footpads of New Zealand White rabbits with 1.7 or 8.4 nmol of tilmanocept labeled with (99m)Tc and a near-infrared fluorophore, IRDye800CW. One and 36 h after injection, popliteal lymph nodes, representing the SLNs, were dissected with the assistance of the FireFly camera system, a fluorescence-capable endoscopic imaging system. After excision of the paraaortic lymph nodes, which represented non-SLNs, we assayed all lymph nodes for radioactivity and fluorescence intensity. Fluorescence within all popliteal lymph nodes was easily detected by the FireFly camera system. Fluorescence within the lymph channel could be imaged during the 1-h studies. When compared with the paraaortic lymph nodes, the popliteal lymph nodes retain greater than 95% of the radioactivity at both 1 and 36 h after injection. At both doses (1.7 and 8.4 nmol), the popliteal nodes had higher (P < 0.050) optical fluorescence intensity than the paraaortic nodes at the 1- and 36-h time points. The FireFly camera system can easily detect tilmanocept labeled with a near-infrared fluorophore at least 36 h after administration. This ability will permit image acquisition and subsequent verification of fluorescence-labeled SLNs during robotic-assisted surgery. © 2014 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Evaluation of chromosomal aberrations induced by 188Re-dendrimer nanosystem on B16f1 melanoma cells.

PubMed

Tassano, Marcos; Oddone, Natalia; Fernández, Marcelo; Porcal, Williams; García, María Fernanda; Martínez-López, Wilner; Benech, Juan Claudio; Cabral, Pablo

2018-06-19

To study the rhenium-188 labeling of polyamidoamine (PAMAM) generation 4 (G4) dendrimer and its evaluation on biodistribution and chromosomal aberrations in melanoma cells induced by ionizing radiation as potential treatment agent. Dendrimers were first conjugated with Suc-HYNIC (succinimidyl 6-hydrazinopyridine-3-carboxylic acid hydrochloride). Dendrimer-HYNIC was then incubated with 188 ReO 4 - . Biodistribution was performed administrating 188 Re-dendrimer to normal (NM) or melanoma-bearing mice (MBM). Chromosome aberration test was conducted in order to measure treatment capacity of 188 Re-dendrimer in melanoma cells. Radiolabeling yield of dendrimer was approx. 70%. Biodistribution studies in NM showed blood clearance with hepatic and renal depuration. MBM showed a similar pattern of biodistribution with tumor uptake of 6% of injected dose. Aberrant metaphases quantified in control cells were 7%, increasing to 29.5% in cells treated with 15μCi (0.555 MBq) of 188 Re-dendrimer for 24 h. 188 Re-dendrimer can produce double-stranded breaks in DNA induced by ionizing radiation in melanoma cells in vitro.

NAS Grid Benchmarks: A Tool for Grid Space Exploration

NASA Technical Reports Server (NTRS)

Frumkin, Michael; VanderWijngaart, Rob F.; Biegel, Bryan (Technical Monitor)

2001-01-01

We present an approach for benchmarking services provided by computational Grids. It is based on the NAS Parallel Benchmarks (NPB) and is called NAS Grid Benchmark (NGB) in this paper. We present NGB as a data flow graph encapsulating an instance of an NPB code in each graph node, which communicates with other nodes by sending/receiving initialization data. These nodes may be mapped to the same or different Grid machines. Like NPB, NGB will specify several different classes (problem sizes). NGB also specifies the generic Grid services sufficient for running the bench-mark. The implementor has the freedom to choose any specific Grid environment. However, we describe a reference implementation in Java, and present some scenarios for using NGB.

Applying self-organizing map and modified radial based neural network for clustering and routing optimal path in wireless network

NASA Astrophysics Data System (ADS)

Hoomod, Haider K.; Kareem Jebur, Tuka

2018-05-01

Mobile ad hoc networks (MANETs) play a critical role in today’s wireless ad hoc network research and consist of active nodes that can be in motion freely. Because it consider very important problem in this network, we suggested proposed method based on modified radial basis function networks RBFN and Self-Organizing Map SOM. These networks can be improved by the use of clusters because of huge congestion in the whole network. In such a system, the performance of MANET is improved by splitting the whole network into various clusters using SOM. The performance of clustering is improved by the cluster head selection and number of clusters. Modified Radial Based Neural Network is very simple, adaptable and efficient method to increase the life time of nodes, packet delivery ratio and the throughput of the network will increase and connection become more useful because the optimal path has the best parameters from other paths including the best bitrate and best life link with minimum delays. Proposed routing algorithm depends on the group of factors and parameters to select the path between two points in the wireless network. The SOM clustering average time (1-10 msec for stall nodes) and (8-75 msec for mobile nodes). While the routing time range (92-510 msec).The proposed system is faster than the Dijkstra by 150-300%, and faster from the RBFNN (without modify) by 145-180%.

Delamination detection by Multi-Level Wavelet Processing of Continuous Scanning Laser Doppler Vibrometry data

NASA Astrophysics Data System (ADS)

Chiariotti, P.; Martarelli, M.; Revel, G. M.

2017-12-01

A novel non-destructive testing procedure for delamination detection based on the exploitation of the simultaneous time and spatial sampling provided by Continuous Scanning Laser Doppler Vibrometry (CSLDV) and the feature extraction capability of Multi-Level wavelet-based processing is presented in this paper. The processing procedure consists in a multi-step approach. Once the optimal mother-wavelet is selected as the one maximizing the Energy to Shannon Entropy Ratio criterion among the mother-wavelet space, a pruning operation aiming at identifying the best combination of nodes inside the full-binary tree given by Wavelet Packet Decomposition (WPD) is performed. The pruning algorithm exploits, in double step way, a measure of the randomness of the point pattern distribution on the damage map space with an analysis of the energy concentration of the wavelet coefficients on those nodes provided by the first pruning operation. A combination of the point pattern distributions provided by each node of the ensemble node set from the pruning algorithm allows for setting a Damage Reliability Index associated to the final damage map. The effectiveness of the whole approach is proven on both simulated and real test cases. A sensitivity analysis related to the influence of noise on the CSLDV signal provided to the algorithm is also discussed, showing that the processing developed is robust enough to measurement noise. The method is promising: damages are well identified on different materials and for different damage-structure varieties.

An experimental model to study the effects of a senna extract on the blood constituent labeling and biodistribution of a radiopharmaceutical in rats.

PubMed

Souza, Deise Elizabeth; Pereira, Marcia Oliveira; Bernardo, Luciana Camargo; Carmo, Fernanda Santos; Fonseca, Adenilson de Souza da; Bernardo-Filho, Mario

2011-01-01

Cassia angustifolia Vahl (senna) is a natural product that contains sennosides, which are active components that affect the intestinal tract and induce diarrhea. Authors have shown that senna produces DNA (deoxyribonucleic acid) lesions in Escherichia coli cultures and can act as an antifungal agent. Natural drugs can alter the labeling of blood constituents with technetium-⁹⁹m (⁹⁹mTc) and can affect the biodistribution of radiopharmaceuticals. In this work, we have evaluated the influence of a senna extract on the radiolabeling of blood constituents and on the biodistribution of the radiopharmaceutical sodium pertechnetate (Na⁹⁹mTcO₄)in Wistar rats. Twelve animals were treated with senna extract for 7 days. Blood samples were withdrawn from the animals and the radiolabeling procedure was carried out. The senna extract did not modify the radiolabeling of the blood constituents. A biodistributional assay was performed by administering Na⁹⁹mTcO₄ and determining its activity in different organs and in blood. The senna extract altered the biodistribution of Na⁹⁹mTcO₄ in the thyroid, liver, pancreas, lungs and blood. These results are associated with properties of the chemical substances present in the aqueous senna extract. Although these assays were performed in animals, our findings suggest that caution should be exercised when nuclear medicine examinations using Na⁹⁹mTcO₄ are conducted in patients who are using senna extract.

An experimental model to study the effects of a senna extract on the blood constituent labeling and biodistribution of a radiopharmaceutical in rats

PubMed Central

Souza, Deise Elizabeth; Pereira, Marcia Oliveira; Bernardo, Luciana Camargo; Carmo, Fernanda Santos; de Souza da Fonseca, Adenilson; Bernardo-Filho, Mario

2011-01-01

ABSTRACT Cassia angustifolia Vahl (senna) is a natural product that contains sennosides, which are active components that affect the intestinal tract and induce diarrhea. Authors have shown that senna produces DNA (deoxyribonucleic acid) lesions in Escherichia coli cultures and can act as an antifungal agent. Natural drugs can alter the labeling of blood constituents with technetium-99m (99mTc) and can affect the biodistribution of radiopharmaceuticals. In this work, we have evaluated the influence of a senna extract on the radiolabeling of blood constituents and on the biodistribution of the radiopharmaceutical sodium pertechnetate (Na99mTcO4) in Wistar rats. Twelve animals were treated with senna extract for 7 days. Blood samples were withdrawn from the animals and the radiolabeling procedure was carried out. The senna extract did not modify the radiolabeling of the blood constituents. A biodistributional assay was performed by administering Na99mTcO4 and determining its activity in different organs and in blood. The senna extract altered the biodistribution of Na99mTcO4 in the thyroid, liver, pancreas, lungs and blood. These results are associated with properties of the chemical substances present in the aqueous senna extract. Although these assays were performed in animals, our findings suggest that caution should be exercised when nuclear medicine examinations using Na99mTcO4 are conducted in patients who are using senna extract. PMID:21552677

Evaluation of 18F-labeled targeted perfluorocarbon-filled albumin microbubbles as a probe for microUS and microPET in tumor-bearing mice.

PubMed

Liao, Ai-Ho; Wu, Shih-Yen; Wang, Hsin-Ell; Weng, Chien-Hsiu; Wu, Ming-Fang; Li, Pai-Chi

2013-02-01

In this study, albumin-shelled, targeted MBs (tMBs) were first demonstrated with the expectation of visualization of biodistribution of albumin-shelled tMBs. The actual biodistribution of albumin-shelled tMBs is of vital importance either for molecular imaging or for drug delivery. Recently, albumin microbubbles (MBs) have been studied for drug and gene delivery in vitro and in vivo through cavitation. Targeted lipid-shelled MBs have been applied for ultrasound molecular imaging and conjugated with radiolabeled antibodies for whole-body biodistribution evaluations. The novelty of the work is that, in addition to the lipid tMBs, the albumin tMBs was also applied in biodistribution detection. Multimodality albumin-shelled, (18)F-SFB-labeled VEGFR2 tMBs were synthesized, and their characteristics in mice bearing MDA-MB-231 human breast cancer were investigated with micro-positron-emission tomography (microPET) and high-frequency ultrasound (microUS). Albumin-shelled MBs can be labeled with (18)F-SFB directly and conjugated with antibodies for dual molecular imaging. The albumin-shelled tMBs show a lifetime in 30min in the blood pool and a highly specific adherence to tumor vessels in mice bearing human breast cancer. From the evaluations of whole-body biodistribution, the potential of the dual molecular imaging probe for drug or gene delivery in animal experiments with albumin shelled MBs has been investigated. Copyright © 2012 Elsevier B.V. All rights reserved.

Nanobarcoding for improved nanoparticle detection in nanomedical biodistribution studies

NASA Astrophysics Data System (ADS)

Eustaquio, Trisha

Determination of the fate of nanoparticles (NPs) in a biological system, or NP biodistribution, is critical in evaluating a NP formulation for nanomedicine. Unlike small-molecule drugs, NPs impose unique challenges in the design of appropriate biodistribution studies due to their small size and subsequent detection signal. Current methods to determine NP biodistribution are greatly inadequate due to their limited detection thresholds. There is an overwhelming need for a sensitive and efficient imaging-based method that can (1) detect and measure small numbers of NPs of various types, ideally single NPs, (2) associate preferential NP uptake with histological cell type by preserving spatial information in samples, and (3) allow for relatively quick and accurate NP detection in in vitro (and possibly ex vivo) samples for comprehensive NP biodistribution studies. Herein, a novel method for improved NP detection is proposed, coined "nanobarcoding." Nanobarcoding utilizes a non-endogenous oligonucleotide, or "nanobarcode" (NB), conjugated to the NP surface to amplify the detection signal from a single NP via in situ polymerase chain reaction (ISPCR), and this signal amplification will facilitate rapid and precise detection of single NPs inside cells over large areas of sample such that more sophisticated studies can be performed on the NP-positive subpopulation. Moreover, nanobarcoding has the potential to be applied to the detection of more than one NP type to study the effects of physicochemical properties, targeting mechanisms, and route of entry on NP biodistribution. The nanobarcoding method was validated in vitro using NB-functionalized superparamagnetic iron oxide NPs (NB-SPIONs) as the model NP type for improved NP detection inside HeLa human cervical cancer cells, a cell line commonly used for ISPCR-mediated detection of human papilloma virus (HPV). Nanotoxicity effects of NB-SPIONs were also evaluated at the single-cell level using LEAP (Laser-Enabled Analysis and Processing, Intrexon, San Diego, CA), and NB-SPIONs were found to be less toxic than its precursor, carboxylated SPIONs (COOH-SPIONs).

Radiolabelled polymeric IgA: from biodistribution to a new molecular imaging tool in colorectal cancer lung metastases

PubMed Central

Carpenet, Helene; Cuvillier, Armelle; Perraud, Aurélie; Martin, Ophélie; Champier, Gaël; Jauberteau, Marie-Odile; Monteil, Jacques; Quelven, Isabelle

2017-01-01

By radiolabelling monomeric (m) and polymeric (p) IgA with technetium 99m (99mTc), this study assessed IgA biodistribution and tumour-targeting potency. IgA directed against carcinoembryonic antigen (CEA), a colorectal cancer marker, was selected to involve IgA mucosal tropism. Ig was radiolabelled with 99mTc-tricarbonyl after derivatisation by 2-iminothiolane. 99mTc-IgA was evaluated by in vitro analysis. The biodistributions of radiolabelled anti-CEA mIgA, pIgA and IgG were compared in normal mice. Anti-CEA pIgA tumour uptake was studied in mice bearing the WiDr caecal orthotopic graft. IgA radiolabelling was obtained with a high yield, was stable in PBS and murine plasma, and did not alter IgA binding functionality (Kd ≈ 25 nM). Biodistribution studies in normal mice confirmed that radiolabelled pIgA – and to a lesser extent, mIgA – showed strong and fast mucosal tropism and a shorter serum half-life than IgG. In caecal tumour model mice, evaluation of the anti-CEA-pIgA biodistribution showed a high uptake in lung metastases, confirmed by histological analysis. However, no radioactivity uptake increase in the tumoural caecum was discerned from normal intestinal tissue, probably due to high IgA caecal natural tropism. In microSPECT/CT imaging, 99mTc-IgA confirmed its diagnostic potency of tumour in mucosal tissue, even if detection threshold by in vivo imaging was higher than post mortem studies. Contribution of the FcαRI receptor, studied with transgenic mouse model (Tsg SCID-CD89), did not appear to be determinant in 99mTc-IgA uptake. Pre-clinical experiments highlighted significant differences between 99mTc-IgA and 99mTc-IgG biodistributions. Furthermore, tumoural model studies suggested potential targeting potency of pIgA in mucosal tissues. PMID:29156712

Incidence and location of lymph node metastases in patients undergoing radical cystectomy for clinical non-muscle invasive bladder cancer: results from a prospective lymph node mapping study.

PubMed

Bruins, Harman M; Skinner, Eila C; Dorin, Ryan P; Ahmadi, Hamed; Djaladat, Hooman; Miranda, Gus; Cai, Jie; Daneshmand, Siamak

2014-01-01

The objective of this study is to investigate the incidence and location of lymph node metastases (LNMs) in patients undergoing radical cystectomy (RC) and lymph node dissection (LND) for clinical non-muscle invasive bladder cancer (NMIBC). Prospectively collected data of 637 patients who underwent RC and 'superextended' LND with intent-to-cure for urothelial carcinoma of the bladder between 2002 and 2008 were examined. Inclusion criteria were (a) clinical stage Ta, Tis-only, or T1, (b) muscle presence at diagnostic transurethral resection in clinical T1 patients, (c) no prior diagnosis of ≥ T2 disease, (d) no neoadjuvant therapy, and (e) lymphatic tissue sample submitted from all 13 predesignated locations. Lymph node mapping was performed in all patients to determine the location of metastatic lymph nodes. Median follow-up time was 4.7 years. Recurrence-free survival and overall survival were reported. A total of 114 patients were included of whom 9 patients (7.9%) had LNM. Stratified by clinical stage, LNM was present in 6/67 (9.0%) patients with cT1, 3/25 (12.0%) patients with cTis-only, and none of the 22 patients with cTa. Of the 9 node-positive patients (33.3%), 3 had LNM proximal to the aortic bifurcation. No skip metastases were found. After RC, 27 patients (23.7%) were upstaged to muscle invasive disease; of whom 16.7% had cT1, 2.6% had cTa, and 4.4% had cTis-only. Of the remaining 87 patients with pathologic NMIBC, 1 patient (1.1%) had LNM, limited to the true pelvis. Five-year RFS was 82.3%, 81.5%, and 62.0% in patients with pathologic NMIBC, clinical NMIBC, and pathologic muscle invasive bladder cancer, respectively. Routine LND is important in patients with cT1 and cTis-only bladder cancer, but may have limited value in patients with cTa. LNM beyond the boundaries of a standard LND occurred in up to one-third of node-positive patients. In the absence of skip metastases, however, performing a standard LND would correctly identify all node-positive patients. Whether removal of LNM proximal to the common iliac vessels provides a survival benefit remains to be evaluated in future prospective studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

Mapping virtual addresses to different physical addresses for value disambiguation for thread memory access requests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gala, Alan; Ohmacht, Martin

A multiprocessor system includes nodes. Each node includes a data path that includes a core, a TLB, and a first level cache implementing disambiguation. The system also includes at least one second level cache and a main memory. For thread memory access requests, the core uses an address associated with an instruction format of the core. The first level cache uses an address format related to the size of the main memory plus an offset corresponding to hardware thread meta data. The second level cache uses a physical main memory address plus software thread meta data to store the memorymore » access request. The second level cache accesses the main memory using the physical address with neither the offset nor the thread meta data after resolving speculation. In short, this system includes mapping of a virtual address to a different physical addresses for value disambiguation for different threads.« less

Altered biodistribution of Ga-67 by intramuscular gold salts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moult, R.G.; Bekerman, C.

1989-11-01

The authors observed a deviation from the normal scintigraphic pattern of Ga-67 citrate biodistribution. An 8-year-old black girl with juvenile rheumatoid arthritis, who had been treated with intramuscular injections of gold salts, had a Ga-67 study as part of her workup. The study demonstrated no hepatic uptake, but showed elevated skeletal and renal activity. This characteristic biodistribution of Ga-67 may be due to inhibition of lysosomal enzymes by gold and/or to accumulation of gold in lysosomes. To study these possibilities, the authors reviewed the mechanisms of Ga-67 localization and gold metabolism. Alteration of the Ga-67 citrate scintigraphic pattern due tomore » earlier treatment with gold salts has not been reported previously.« less

In Vitro and In Vivo Behaviour of 111In Complexes of TTHA, TTHA-Bis(Butylamide) and TTHA-Bis(Glucamide): Stability, Biodistribution and Excretion Studied by Gamma Imaging

PubMed Central

Prata, M. I. M.; Ribeiro, M. J.; Santos, A. C.; Peters, J. A.; Nepveu, F.; de Lima, J. J. P.

1998-01-01

Aiming at radiopharmaceutical application, 111In3+ complexes of the polyaminocarboxylates TTHA, TTHA-bis(butylamide) and TTHA-bis(glucamide) were investigated. The in vitro stability of 111In(TTHA)3− and 111In(TTHA-bis(butylamide)- was evaluated by measuring the exchange of 111In3+ from the complexes to transferrin and the results were compared with those for 111In(DTPA)2−. We also performed biodistribution studies of the three 111In3+ complexes by gamma-imaging in Wistar rats and by measuring the radioactivity in their organs. TTHA and its derivatives seem to have similar in vivo biodistribution with prevailing renal excretion. PMID:18475854

Molecular analysis of breast sentinel lymph nodes.

PubMed

Blumencranz, Peter W; Pieretti, Maura; Allen, Kathleen G; Blumencranz, Lisa E

2011-07-01

Lymphatic mapping and sentinel lymph node (SLN) biopsy have become the standard of care for staging the axilla in patients with invasive breast cancer. Current histologic methods for SLN evaluation have limitations, including subjectivity, limited sensitivity, and lack of standardization. The discovery of molecular markers to detect metastases has been reported over the last 2 decades. The authors review the historical development of these markers and the clinical use of one of the molecular platforms in 478 patients at their institution. Controversies and future directions are discussed. Copyright © 2011 Elsevier Inc. All rights reserved.

Multimodal imaging of lymph nodes and tumors using glycol-chitosan-coated gold nanoparticles (Conference Presentation)

NASA Astrophysics Data System (ADS)

Sun, In-Cheol; Dumani, Diego S.; Emelianov, Stanislav Y.

2017-03-01

A key step in staging cancer is the diagnosis of metastasis that spreads through lymphatic system. For this reason, researchers develop various methods of sentinel lymph node mapping that often use a radioactive tracer. This study introduces a safe, cost-effective, high-resolution, high-sensitivity, and real-time method of visualizing the sentinel lymph node: ultrasound-guided photoacoustic (US/PA) imaging augmented by a contrast agent. In this work, we use clearable gold nanoparticles covered by a biocompatible polymer (glycol chitosan) to enhance cellular uptake by macrophages abundant in lymph nodes. We incubate macrophages with glycol-chitosan-coated gold nanoparticles (0.05 mg Au/ml), and then fix them with paraformaldehyde solution for an analysis of in vitro dark-field microscopy and cell phantom. The analysis shows enhanced cellular uptake of nanoparticles by macrophages and strong photoacoustic signal from labeled cells in tissue-mimicking cell phantoms consisting gelatin solution (6 %) with silica gel (25 μm, 0.3%) and fixed macrophages. The in-vivo US/PA imaging of cervical lymph nodes in healthy mice (nu/nu, female, 5 weeks) indicates a strong photoacoustic signal from a lymph node 10 minutes post-injection (2.5 mg Au/ml, 80 μl). The signal intensity and the nanoparticle-labeled volume of tissue within the lymph node continues to increase until 4 h post-injection. Histological analysis further confirms the accumulation of gold nanoparticles within the lymph nodes. This work suggests the feasibility of molecular/cellular US/PA imaging with biocompatible gold nanoparticles as a photoacoustic contrast agent in the diagnosis of lymph-node-related diseases.

Use of 99mTc-Tilmanocept as a Single Agent for Sentinel Lymph Node Identification in Breast Cancer: A Retrospective Pilot Study.

PubMed

Unkart, Jonathan T; Wallace, Anne M

2017-09-01

99m Tc-tilmanocept received recent Food and Drug Administration approval for lymphatic mapping in 2013. However, to our knowledge, no prior studies have evaluated the use of 99m Tc-tilmanocept as a single agent in sentinel lymph node (SLN) biopsy in breast cancer. Methods: We executed this retrospective pilot study to assess the ability of 99m Tc-tilmanocept to identify sentinel nodes as a single agent in clinically node-negative breast cancer patients. Patients received a single intradermal injection overlying the tumor of either 18.5 MBq (0.5 mCi) of 99m Tc-tilmanocept on the day of surgery or 74.0 MBq (2.0 mCi) on the day before surgery by a radiologist. Immediate 3-view lymphoscintigraphy was performed. Intraoperatively, SLNs were identified with a portable γ-probe. A node was classified as hot if the count (per second) of the node was more than 3 times the background count. Descriptive statistics are reported. Results: Nineteen patients underwent SLN biopsy with single-agent 99m Tc-tilmanocept. Immediate lymphoscintigraphy identified at least 1 sentinel node in 13 of 17 patients (76.5%). Intraoperatively, at least 1 (mean, 1.7 ± 0.8; range, 1-3) hot node was identified in all patients. Three patients (15.8%) had 1 disease-positive SLN. Conclusion: In this small, retrospective pilot study, 99m Tc-tilmanocept performed well as a single agent for intraoperative sentinel node identification in breast cancer. A larger, randomized clinical trial is warranted to compare 99m Tc-tilmanocept as a single agent with other radiopharmaceuticals for sentinel node identification in breast cancer. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

Adaptive Data Gathering in Mobile Sensor Networks Using Speedy Mobile Elements

PubMed Central

Lai, Yongxuan; Xie, Jinshan; Lin, Ziyu; Wang, Tian; Liao, Minghong

2015-01-01

Data gathering is a key operator for applications in wireless sensor networks; yet it is also a challenging problem in mobile sensor networks when considering that all nodes are mobile and the communications among them are opportunistic. This paper proposes an efficient data gathering scheme called ADG that adopts speedy mobile elements as the mobile data collector and takes advantage of the movement patterns of the network. ADG first extracts the network meta-data at initial epochs, and calculates a set of proxy nodes based on the meta-data. Data gathering is then mapped into the Proxy node Time Slot Allocation (PTSA) problem that schedules the time slots and orders, according to which the data collector could gather the maximal amount of data within a limited period. Finally, the collector follows the schedule and picks up the sensed data from the proxy nodes through one hop of message transmissions. ADG learns the period when nodes are relatively stationary, so that the collector is able to pick up the data from them during the limited data gathering period. Moreover, proxy nodes and data gathering points could also be timely updated so that the collector could adapt to the change of node movements. Extensive experimental results show that the proposed scheme outperforms other data gathering schemes on the cost of message transmissions and the data gathering rate, especially under the constraint of limited data gathering period. PMID:26389903

SSL: Signal Similarity-Based Localization for Ocean Sensor Networks.

PubMed

Chen, Pengpeng; Ma, Honglu; Gao, Shouwan; Huang, Yan

2015-11-24

Nowadays, wireless sensor networks are often deployed on the sea surface for ocean scientific monitoring. One of the important challenges is to localize the nodes' positions. Existing localization schemes can be roughly divided into two types: range-based and range-free. The range-based localization approaches heavily depend on extra hardware capabilities, while range-free ones often suffer from poor accuracy and low scalability, far from the practical ocean monitoring applications. In response to the above limitations, this paper proposes a novel signal similarity-based localization (SSL) technology, which localizes the nodes' positions by fully utilizing the similarity of received signal strength and the open-air characteristics of the sea surface. In the localization process, we first estimate the relative distance between neighboring nodes through comparing the similarity of received signal strength and then calculate the relative distance for non-neighboring nodes with the shortest path algorithm. After that, the nodes' relative relation map of the whole network can be obtained. Given at least three anchors, the physical locations of nodes can be finally determined based on the multi-dimensional scaling (MDS) technology. The design is evaluated by two types of ocean experiments: a zonal network and a non-regular network using 28 nodes. Results show that the proposed design improves the localization accuracy compared to typical connectivity-based approaches and also confirm its effectiveness for large-scale ocean sensor networks.

Impact of sentinel lymphadenectomy on survival in a murine model of melanoma.

PubMed

Rebhun, Robert B; Lazar, Alexander J F; Fidler, Isaiah J; Gershenwald, Jeffrey E

2008-01-01

Lymphatic mapping and sentinel lymph node biopsy-also termed sentinel lymphadenectomy (SL)-has become a standard of care for patients with primary invasive cutaneous melanoma. This technique has been shown to provide accurate information about the disease status of the regional lymph node basins at risk for metastasis, provide prognostic information, and provide durable regional lymph node control. The potential survival benefit afforded to patients undergoing SL is controversial. Central to this controversy is whether metastasis to regional lymph nodes occurs independent of or prior to widespread hematogenous dissemination. A related area of uncertainty is whether tumor cells residing within regional lymph nodes have increased metastatic potential. We have used a murine model of primary invasive cutaneous melanoma based on injection of B16-BL6 melanoma cells into the pinna to address two questions: (1) does SL plus wide excision of the primary tumor result in a survival advantage over wide excision alone; and (2) do melanoma cells growing within lymph nodes produce a higher incidence of hematogenous metastases than do cells growing at the primary tumor site? We found that SL significantly improved the survival of mice with small primary tumors. We found no difference in the incidence of lung metastases produced by B16-BL6 melanoma cells growing exclusively within regional lymph nodes and cells growing within the pinna.

Resource-aware system architecture model for implementation of quantum aided Byzantine agreement on quantum repeater networks

NASA Astrophysics Data System (ADS)

Taherkhani, Mohammand Amin; Navi, Keivan; Van Meter, Rodney

2018-01-01

Quantum aided Byzantine agreement is an important distributed quantum algorithm with unique features in comparison to classical deterministic and randomized algorithms, requiring only a constant expected number of rounds in addition to giving a higher level of security. In this paper, we analyze details of the high level multi-party algorithm, and propose elements of the design for the quantum architecture and circuits required at each node to run the algorithm on a quantum repeater network (QRN). Our optimization techniques have reduced the quantum circuit depth by 44% and the number of qubits in each node by 20% for a minimum five-node setup compared to the design based on the standard arithmetic circuits. These improvements lead to a quantum system architecture with 160 qubits per node, space-time product (an estimate of the required fidelity) {KQ}≈ 1.3× {10}5 per node and error threshold 1.1× {10}-6 for the total nodes in the network. The evaluation of the designed architecture shows that to execute the algorithm once on the minimum setup, we need to successfully distribute a total of 648 Bell pairs across the network, spread evenly between all pairs of nodes. This framework can be considered a starting point for establishing a road-map for light-weight demonstration of a distributed quantum application on QRNs.

Samarium oxide as a radiotracer to evaluate the in vivo biodistribution of PLGA nanoparticles

NASA Astrophysics Data System (ADS)

Mandiwana, Vusani; Kalombo, Lonji; Venter, Kobus; Sathekge, Mike; Grobler, Anne; Zeevaart, Jan Rijn

2015-09-01

Developing nanoparticulate delivery systems that will allow easy movement and localization of a drug to the target tissue and provide more controlled release of the drug in vivo is a challenge in nanomedicine. The aim of this study was to evaluate the biodistribution of poly( d, l-lactide- co-glycolide) (PLGA) nanoparticles containing samarium-153 oxide ([153Sm]Sm2O3) in vivo to prove that orally administered nanoparticles alter the biodistribution of a drug. These were then activated in a nuclear reactor to produce radioactive 153Sm-loaded-PLGA nanoparticles. The nanoparticles were characterized for size, zeta potential, and morphology. The nanoparticles were orally and intravenously (IV) administered to rats in order to trace their uptake through imaging and biodistribution studies. The 153Sm-loaded-PLGA nanoparticles had an average size of 281 ± 6.3 nm and a PDI average of 0.22. The zeta potential ranged between 5 and 20 mV. The [153Sm]Sm2O3 loaded PLGA nanoparticles, orally administered were distributed to most organs at low levels, indicating that there was absorption of nanoparticles. While the IV injected [153Sm]Sm2O3-loaded PLGA nanoparticles exhibited the highest localization of nanoparticles in the spleen (8.63 %ID/g) and liver (3.07 %ID/g), confirming that nanoparticles are rapidly removed from the blood by the RES, leading to rapid uptake in the liver and spleen. From the biodistribution data obtained, it is clear that polymeric nanoscale delivery systems would be suitable for improving permeability and thus the bioavailability of therapeutic compounds.

Selection of an optimal cysteine-containing peptide-based chelator for labeling of affibody molecules with (188)Re.

PubMed

Altai, Mohamed; Honarvar, Hadis; Wållberg, Helena; Strand, Joanna; Varasteh, Zohreh; Rosestedt, Maria; Orlova, Anna; Dunås, Finn; Sandström, Mattias; Löfblom, John; Tolmachev, Vladimir; Ståhl, Stefan

2014-11-24

Affibody molecules constitute a class of small (7 kDa) scaffold proteins that can be engineered to have excellent tumor targeting properties. High reabsorption in kidneys complicates development of affibody molecules for radionuclide therapy. In this study, we evaluated the influence of the composition of cysteine-containing C-terminal peptide-based chelators on the biodistribution and renal retention of (188)Re-labeled anti-HER2 affibody molecules. Biodistribution of affibody molecules containing GGXC or GXGC peptide chelators (where X is G, S, E or K) was compared with biodistribution of a parental affibody molecule ZHER2:2395 having a KVDC peptide chelator. All constructs retained low picomolar affinity to HER2-expressing cells after labeling. The biodistribution of all (188)Re-labeled affibody molecules was in general comparable, with the main observed difference found in the uptake and retention of radioactivity in excretory organs. The (188)Re-ZHER2:V2 affibody molecule with a GGGC chelator provided the lowest uptake in all organs and tissues. The renal retention of (188)Re-ZHER2:V2 (3.1 ± 0.5 %ID/g at 4 h after injection) was 55-fold lower than retention of the parental (188)Re-ZHER2:2395 (172 ± 32 %ID/g). We show that engineering of cysteine-containing peptide-based chelators can be used for significant improvement of biodistribution of (188)Re-labeled scaffold proteins, particularly reduction of their uptake in excretory organs. Copyright © 2014 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

A coherent Ising machine for 2000-node optimization problems

NASA Astrophysics Data System (ADS)

Inagaki, Takahiro; Haribara, Yoshitaka; Igarashi, Koji; Sonobe, Tomohiro; Tamate, Shuhei; Honjo, Toshimori; Marandi, Alireza; McMahon, Peter L.; Umeki, Takeshi; Enbutsu, Koji; Tadanaga, Osamu; Takenouchi, Hirokazu; Aihara, Kazuyuki; Kawarabayashi, Ken-ichi; Inoue, Kyo; Utsunomiya, Shoko; Takesue, Hiroki

2016-11-01

The analysis and optimization of complex systems can be reduced to mathematical problems collectively known as combinatorial optimization. Many such problems can be mapped onto ground-state search problems of the Ising model, and various artificial spin systems are now emerging as promising approaches. However, physical Ising machines have suffered from limited numbers of spin-spin couplings because of implementations based on localized spins, resulting in severe scalability problems. We report a 2000-spin network with all-to-all spin-spin couplings. Using a measurement and feedback scheme, we coupled time-multiplexed degenerate optical parametric oscillators to implement maximum cut problems on arbitrary graph topologies with up to 2000 nodes. Our coherent Ising machine outperformed simulated annealing in terms of accuracy and computation time for a 2000-node complete graph.

Fluorine-19 nuclear magnetic resonance of chimeric antigen receptor T cell biodistribution in murine cancer model.

PubMed

Chapelin, Fanny; Gao, Shang; Okada, Hideho; Weber, Thomas G; Messer, Karen; Ahrens, Eric T

2017-12-18

Discovery of effective cell therapies against cancer can be accelerated by the adaptation of tools to rapidly quantitate cell biodistribution and survival after delivery. Here, we describe the use of nuclear magnetic resonance (NMR) 'cytometry' to quantify the biodistribution of immunotherapeutic T cells in intact tissue samples. In this study, chimeric antigen receptor (CAR) T cells expressing EGFRvIII targeting transgene were labeled with a perfluorocarbon (PFC) emulsion ex vivo and infused into immunocompromised mice bearing subcutaneous human U87 glioblastomas expressing EGFRvIII and luciferase. Intact organs were harvested at day 2, 7 and 14 for whole-sample fluorine-19 ( 19 F) NMR to quantitatively measure the presence of PFC-labeled CAR T cells, followed by histological validation. NMR measurements showed greater CAR T cell homing and persistence in the tumors and spleen compared to untransduced T cells. Tumor growth was monitored with bioluminescence imaging, showing that CAR T cell treatment resulted in significant tumor regression compared to untransduced T cells. Overall, 19 F NMR cytometry is a rapid and quantitative method to evaluate cell biodistribution, tumor homing, and fate in preclinical studies.

Fc-Mediated Anomalous Biodistribution of Therapeutic Antibodies in Immunodeficient Mouse Models.

PubMed

Sharma, Sai Kiran; Chow, Andrew; Monette, Sebastien; Vivier, Delphine; Pourat, Jacob; Edwards, Kimberly J; Dilling, Thomas R; Abdel-Atti, Dalya; Zeglis, Brian M; Poirier, John T; Lewis, Jason S

2018-04-01

A critical benchmark in the development of antibody-based therapeutics is demonstration of efficacy in preclinical mouse models of human disease, many of which rely on immunodeficient mice. However, relatively little is known about how the biology of various immunodeficient strains impacts the in vivo fate of these drugs. Here we used immunoPET radiotracers prepared from humanized, chimeric, and murine mAbs against four therapeutic oncologic targets to interrogate their biodistribution in four different strains of immunodeficient mice bearing lung, prostate, and ovarian cancer xenografts. The immunodeficiency status of the mouse host as well as both the biological origin and glycosylation of the antibody contributed significantly to the anomalous biodistribution of therapeutic monoclonal antibodies in an Fc receptor-dependent manner. These findings may have important implications for the preclinical evaluation of Fc-containing therapeutics and highlight a clear need for biodistribution studies in the early stages of antibody drug development. Significance: Fc/FcγR-mediated immunobiology of the experimental host is a key determinant to preclinical in vivo tumor targeting and efficacy of therapeutic antibodies. Cancer Res; 78(7); 1820-32. ©2018 AACR . ©2018 American Association for Cancer Research.

Binding Affinity, Specificity and Comparative Biodistribution of the Parental Murine Monoclonal Antibody MX35 (Anti-NaPi2b) and Its Humanized Version Rebmab200

PubMed Central

Lindegren, Sture; Andrade, Luciana N. S.; Bäck, Tom; Machado, Camila Maria L.; Horta, Bruno Brasil; Buchpiguel, Carlos; Moro, Ana Maria; Okamoto, Oswaldo Keith; Jacobsson, Lars; Cederkrantz, Elin; Washiyama, Kohshin; Aneheim, Emma; Palm, Stig; Jensen, Holger; Tuma, Maria Carolina B.; Chammas, Roger; Hultborn, Ragnar; Albertsson, Per

2015-01-01

The aim of this preclinical study was to evaluate the characteristics of the monoclonal antibody Rebmab200, which is a humanized version of the ovarian-specific murine antibody MX35. This investigation contributes to the foundation for future clinical α-radioimmunotherapy of minimal residual ovarian cancer with 211At-Rebmab200. Here, the biodistribution of 211At-Rebmab200 was evaluated, as was the utility of 99mTc-Rebmab200 for bioimaging. Rebmab200 was directly compared with its murine counterpart MX35 in terms of its in-vitro capacity for binding the immobilized NaPi2B epitope and live cells; we also assessed its biodistribution in nude mice carrying subcutaneous OVCAR-3 tumors. Tumor antigen and cell binding were similar between Rebmab200 and murine MX35, as was biodistribution, including normal tissue uptake and in-vivo tumor binding. We also demonstrated that 99mTc-Rebmab200 can be used for single-photon emission computed tomography of subcutaneous ovarian carcinomas in tumor-bearing mice. Taken together, our data support the further development of Rebmab200 for radioimmunotherapy and diagnostics. PMID:25970341

Binding Affinity, Specificity and Comparative Biodistribution of the Parental Murine Monoclonal Antibody MX35 (Anti-NaPi2b) and Its Humanized Version Rebmab200.

PubMed

Lindegren, Sture; Andrade, Luciana N S; Bäck, Tom; Machado, Camila Maria L; Horta, Bruno Brasil; Buchpiguel, Carlos; Moro, Ana Maria; Okamoto, Oswaldo Keith; Jacobsson, Lars; Cederkrantz, Elin; Washiyama, Kohshin; Aneheim, Emma; Palm, Stig; Jensen, Holger; Tuma, Maria Carolina B; Chammas, Roger; Hultborn, Ragnar; Albertsson, Per

2015-01-01

The aim of this preclinical study was to evaluate the characteristics of the monoclonal antibody Rebmab200, which is a humanized version of the ovarian-specific murine antibody MX35. This investigation contributes to the foundation for future clinical α-radioimmunotherapy of minimal residual ovarian cancer with 211At-Rebmab200. Here, the biodistribution of 211At-Rebmab200 was evaluated, as was the utility of 99mTc-Rebmab200 for bioimaging. Rebmab200 was directly compared with its murine counterpart MX35 in terms of its in-vitro capacity for binding the immobilized NaPi2B epitope and live cells; we also assessed its biodistribution in nude mice carrying subcutaneous OVCAR-3 tumors. Tumor antigen and cell binding were similar between Rebmab200 and murine MX35, as was biodistribution, including normal tissue uptake and in-vivo tumor binding. We also demonstrated that 99mTc-Rebmab200 can be used for single-photon emission computed tomography of subcutaneous ovarian carcinomas in tumor-bearing mice. Taken together, our data support the further development of Rebmab200 for radioimmunotherapy and diagnostics.

Mutations in GLDN, Encoding Gliomedin, a Critical Component of the Nodes of Ranvier, Are Responsible for Lethal Arthrogryposis.

PubMed

Maluenda, Jérôme; Manso, Constance; Quevarec, Loic; Vivanti, Alexandre; Marguet, Florent; Gonzales, Marie; Guimiot, Fabien; Petit, Florence; Toutain, Annick; Whalen, Sandra; Grigorescu, Romulus; Coeslier, Anne Dieux; Gut, Marta; Gut, Ivo; Laquerrière, Annie; Devaux, Jérôme; Melki, Judith

2016-10-06

Arthrogryposis multiplex congenita (AMC) is a developmental condition characterized by multiple joint contractures resulting from reduced or absent fetal movements. Through linkage analysis, homozygosity mapping, and exome sequencing in four unrelated families affected by lethal AMC, we identified biallelic mutations in GLDN in the affected individuals. GLDN encodes gliomedin, a secreted cell adhesion molecule involved in the formation of the nodes of Ranvier. Transmission electron microscopy of the sciatic nerve from one of the affected individuals showed a marked lengthening defect of the nodes. The GLDN mutations found in the affected individuals abolish the cell surface localization of gliomedin and its interaction with its axonal partner, neurofascin-186 (NF186), in a cell-based assay. The axoglial contact between gliomedin and NF186 is essential for the initial clustering of Na + channels at developing nodes. These results indicate a major role of gliomedin in node formation and the development of the peripheral nervous system in humans. These data indicate that mutations of GLDN or CNTNAP1 (MIM: 616286), encoding essential components of the nodes of Ranvier and paranodes, respectively, lead to inherited nodopathies, a distinct disease entity among peripheral neuropathies. Copyright © 2016 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Sentinel lymph nodes detection with an imaging system using Patent Blue V dye as fluorescent tracer

NASA Astrophysics Data System (ADS)

Tellier, F.; Steibel, J.; Chabrier, R.; Rodier, J. F.; Pourroy, G.; Poulet, P.

2013-03-01

Sentinel lymph node biopsy is the gold standard to detect metastatic invasion from primary breast cancer. This method can help patients avoid full axillary chain dissection, thereby decreasing the risk of morbidity. We propose an alternative to the traditional isotopic method, to detect and map the sentinel lymph nodes. Indeed, Patent Blue V is the most widely used dye in clinical routine for the visual detection of sentinel lymph nodes. A Recent study has shown the possibility of increasing the fluorescence quantum yield of Patent Blue V, when it is bound to human serum albumin. In this study we present a preclinical fluorescence imaging system to detect sentinel lymph nodes labeled with this fluorescent tracer. The setup is composed of a black and white CCD camera and two laser sources. One excitation source with a laser emitting at 635 nm and a second laser at 785 nm to illuminate the region of interest. The prototype is operated via a laptop. Preliminary experiments permitted to determine the device sensitivity in the μmol.L-1 range as regards the detection of PBV fluorescence signals. We also present a preclinical evaluation performed on Lewis rats, during which the fluorescence imaging setup detected the accumulation and fixation of the fluorescent dye on different nodes through the skin.

A hybrid 3D spatial access method based on quadtrees and R-trees for globe data

NASA Astrophysics Data System (ADS)

Gong, Jun; Ke, Shengnan; Li, Xiaomin; Qi, Shuhua

2009-10-01

3D spatial access method for globe data is very crucial technique for virtual earth. This paper presents a brand-new maintenance method to index 3d objects distributed on the whole surface of the earth, which integrates the 1:1,000,000- scale topographic map tiles, Quad-tree and R-tree. Furthermore, when traditional methods are extended into 3d space, the performance of spatial index deteriorates badly, for example 3D R-tree. In order to effectively solve this difficult problem, a new algorithm of dynamic R-tree is put forward, which includes two sub-procedures, namely node-choosing and node-split. In the node-choosing algorithm, a new strategy is adopted, not like the traditional mode which is from top to bottom, but firstly from bottom to top then from top to bottom. This strategy can effectively solve the negative influence of node overlap. In the node-split algorithm, 2-to-3 split mode substitutes the traditional 1-to-2 mode, which can better concern the shape and size of nodes. Because of the rational tree shape, this R-tree method can easily integrate the concept of LOD. Therefore, it will be later implemented in commercial DBMS and adopted in time-crucial 3d GIS system.

DMP: Detouring Using Multiple Paths against Jamming Attack for Ubiquitous Networking System

PubMed Central

Kim, Mihui; Chae, Kijoon

2010-01-01

To successfully realize the ubiquitous network environment including home automation or industrial control systems, it is important to be able to resist a jamming attack. This has recently been considered as an extremely threatening attack because it can collapse the entire network, despite the existence of basic security protocols such as encryption and authentication. In this paper, we present a method of jamming attack tolerant routing using multiple paths based on zones. The proposed scheme divides the network into zones, and manages the candidate forward nodes of neighbor zones. After detecting an attack, detour nodes decide zones for rerouting, and detour packets destined for victim nodes through forward nodes in the decided zones. Simulation results show that our scheme increases the PDR (Packet Delivery Ratio) and decreases the delay significantly in comparison with rerouting by a general routing protocol on sensor networks, AODV (Ad hoc On Demand Distance Vector), and a conventional JAM (Jammed Area Mapping) service with one reroute. PMID:22319316

DMP: detouring using multiple paths against jamming attack for ubiquitous networking system.

PubMed

Kim, Mihui; Chae, Kijoon

2010-01-01

To successfully realize the ubiquitous network environment including home automation or industrial control systems, it is important to be able to resist a jamming attack. This has recently been considered as an extremely threatening attack because it can collapse the entire network, despite the existence of basic security protocols such as encryption and authentication. In this paper, we present a method of jamming attack tolerant routing using multiple paths based on zones. The proposed scheme divides the network into zones, and manages the candidate forward nodes of neighbor zones. After detecting an attack, detour nodes decide zones for rerouting, and detour packets destined for victim nodes through forward nodes in the decided zones. Simulation results show that our scheme increases the PDR (Packet Delivery Ratio) and decreases the delay significantly in comparison with rerouting by a general routing protocol on sensor networks, AODV (Ad hoc On Demand Distance Vector), and a conventional JAM (Jammed Area Mapping) service with one reroute.

Mapping a Nursing Terminology Subset to openEHR Archetypes. A Case Study of the International Classification for Nursing Practice.

PubMed

Nogueira, J R M; Cook, T W; Cavalini, L T

2015-01-01

Healthcare information technologies have the potential to transform nursing care. However, healthcare information systems based on conventional software architecture are not semantically interoperable and have high maintenance costs. Health informatics standards, such as controlled terminologies, have been proposed to improve healthcare information systems, but their implementation in conventional software has not been enough to overcome the current challenge. Such obstacles could be removed by adopting a multilevel model-driven approach, such as the openEHR specifications, in nursing information systems. To create an openEHR archetype model for the Functional Status concepts as published in Nursing Outcome Indicators Catalog of the International Classification for Nursing Practice (NOIC-ICNP). Four methodological steps were followed: 1) extraction of terms from the NOIC-ICNP terminology; 2) identification of previously published openEHR archetypes; 3) assessment of the adequacy of those openEHR archetypes to represent the terms; and 4) development of new openEHR archetypes when required. The "Barthel Index" archetype was retrieved and mapped to the 68 NOIC-ICNP Functional Status terms. There were 19 exact matches between a term and the correspondent archetype node and 23 archetype nodes that matched to one or more NOIC-INCP. No matches were found between the archetype and 14 of the NOIC-ICNP terms, and nine archetype nodes did not match any of the NOIC-ICNP terms. The openEHR model was sufficient to represent the semantics of the Functional Status concept according to the NOIC-ICNP, but there were differences in data granularity between the terminology and the archetype, thus producing a significantly complex mapping, which could be difficult to implement in real healthcare information systems. However, despite the technological complexity, the present study demonstrated the feasibility of mapping nursing terminologies to openEHR archetypes, which emphasizes the importance of adopting the multilevel model-driven approach for the achievement of semantic interoperability between healthcare information systems.

Astronomy in the Cloud: Using MapReduce for Image Co-Addition

NASA Astrophysics Data System (ADS)

Wiley, K.; Connolly, A.; Gardner, J.; Krughoff, S.; Balazinska, M.; Howe, B.; Kwon, Y.; Bu, Y.

2011-03-01

In the coming decade, astronomical surveys of the sky will generate tens of terabytes of images and detect hundreds of millions of sources every night. The study of these sources will involve computation challenges such as anomaly detection and classification and moving-object tracking. Since such studies benefit from the highest-quality data, methods such as image co-addition, i.e., astrometric registration followed by per-pixel summation, will be a critical preprocessing step prior to scientific investigation. With a requirement that these images be analyzed on a nightly basis to identify moving sources such as potentially hazardous asteroids or transient objects such as supernovae, these data streams present many computational challenges. Given the quantity of data involved, the computational load of these problems can only be addressed by distributing the workload over a large number of nodes. However, the high data throughput demanded by these applications may present scalability challenges for certain storage architectures. One scalable data-processing method that has emerged in recent years is MapReduce, and in this article we focus on its popular open-source implementation called Hadoop. In the Hadoop framework, the data are partitioned among storage attached directly to worker nodes, and the processing workload is scheduled in parallel on the nodes that contain the required input data. A further motivation for using Hadoop is that it allows us to exploit cloud computing resources: i.e., platforms where Hadoop is offered as a service. We report on our experience of implementing a scalable image-processing pipeline for the SDSS imaging database using Hadoop. This multiterabyte imaging data set provides a good testbed for algorithm development, since its scope and structure approximate future surveys. First, we describe MapReduce and how we adapted image co-addition to the MapReduce framework. Then we describe a number of optimizations to our basic approach and report experimental results comparing their performance.

Is a More Comprehensive Surgery Necessary in Patients With Uterine Serous Carcinoma?

PubMed

Touhami, Omar; Trinh, Xuan-Bich; Gregoire, Jean; Sebastianelli, Alexandra; Renaud, Marie-Claude; Grondin, Katherine; Plante, Marie

2015-09-01

Uterine serous carcinoma (USC) is an aggressive histologic subtype of endometrial cancer that shares similarities to serous ovarian cancer, with a propensity for spread to the upper abdomen, a high recurrence rate, and a poor prognosis. The aim of this study was to determine whether the traditional surgical staging procedure for endometrial cancer was adequate for USC or whether a more extensive surgery, similar to the staging procedure for ovarian cancer, needs to be performed. Specifically, the roles of omentectomy and sentinel lymph node (SLN) mapping were evaluated. We retrospectively identified cases of presumed clinical stage I USC at our institution from April 2005 to March 2014. Medical records were reviewed for the following information: age at diagnosis, preoperative imaging, operative findings, surgical procedure, and final histology with definitive International Federation of Gynecology and Obstetrics stage. A total of 39 patients with presumed clinical stage I USC were identified. According to the final pathology report, the surgical stage was as follows: 17 stage IA (44%), 8 stage IB (20%), 3 stage II (8%), 2 stage IIIA (5%), 6 stage IIIC1 (15%), 1 IIIC2 (3%), and 2 stage IVB (5%). Therefore, 14 patients (36%) were surgically upstaged, but none of the patients had their clinical disease upstaged by virtue of finding microscopic metastatic disease in an otherwise normal-looking omentum. Sentinel lymph node mapping was performed in 19 patients (42%). Sensitivity and negative predictive value of SLN mapping were 100% when at least 1 SLN was identified. The detection of microscopic disease in radiologically and clinically normal-appearing omentum seems to be rare in USC. Sentinel lymph node mapping seems to be valuable in the serous subtype of endometrial cancer. A less extensive surgery may be possible in patients with USC as it seems to provide the same information as a more extensive surgery.

Biodistribution and pharmacokinetics of Mad2 siRNA-loaded EGFR-targeted chitosan nanoparticles in cisplatin sensitive and resistant lung cancer models.

PubMed

Nascimento, Ana Vanessa; Gattacceca, Florence; Singh, Amit; Bousbaa, Hassan; Ferreira, Domingos; Sarmento, Bruno; Amiji, Mansoor M

2016-04-01

The present study focuses on biodistribution profile and pharmacokinetic parameters of EGFR-targeted chitosan nanoparticles (TG CS nanoparticles) for siRNA/cisplatin combination therapy of lung cancer. Mad2 siRNA was encapsulated in EGFR targeted and nontargeted (NTG) CS nanoparticles by electrostatic interaction. The biodistribution of the nanoparticles was assessed qualitatively and quantitatively in cisplatin (DDP) sensitive and resistant lung cancer xenograft model. TG nanoparticles showed a consistent and preferential tumor targeting ability with rapid clearance from the plasma to infiltrate and sustain within the tumor up to 96 h. They exhibit a sixfold higher tumor targeting efficiency compared with the NTG nanoparticles. TG nanoparticles present as an attractive drug delivery platform for RNAi therapeutics against NSCLC.

High-accuracy biodistribution analysis of adeno-associated virus variants by double barcode sequencing.

PubMed

Marsic, Damien; Méndez-Gómez, Héctor R; Zolotukhin, Sergei

2015-01-01

Biodistribution analysis is a key step in the evaluation of adeno-associated virus (AAV) capsid variants, whether natural isolates or produced by rational design or directed evolution. Indeed, when screening candidate vectors, accurate knowledge about which tissues are infected and how efficiently is essential. We describe the design, validation, and application of a new vector, pTR-UF50-BC, encoding a bioluminescent protein, a fluorescent protein and a DNA barcode, which can be used to visualize localization of transduction at the organism, organ, tissue, or cellular levels. In addition, by linking capsid variants to different barcoded versions of the vector and amplifying the barcode region from various tissue samples using barcoded primers, biodistribution of viral genomes can be analyzed with high accuracy and efficiency.

Image Guided Biodistribution and Pharmacokinetic Studies of Theranostics

PubMed Central

Ding, Hong; Wu, Fang

2012-01-01

Image guided technique is playing an increasingly important role in the investigation of the biodistribution and pharmacokinetics of drugs or drug delivery systems in various diseases, especially cancers. Besides anatomical imaging modalities such as computed tomography (CT), magnetic resonance imaging (MRI), molecular imaging strategy including optical imaging, positron emission tomography (PET) and single-photon emission computed tomography (SPECT) will facilitate the localization and quantization of radioisotope or optical probe labeled nanoparticle delivery systems in the category of theranostics. The quantitative measurement of the bio-distribution and pharmacokinetics of theranostics in the fields of new drug/probe development, diagnosis and treatment process monitoring as well as tracking the brain-blood-barrier (BBB) breaking through by high sensitive imaging method, and the applications of the representative imaging modalities are summarized in this review. PMID:23227121

Intraoperative analysis of sentinel lymph nodes by imprint cytology for cancer of the breast.

PubMed

Shiver, Stephen A; Creager, Andrew J; Geisinger, Kim; Perrier, Nancy D; Shen, Perry; Levine, Edward A

2002-11-01

The utilization of lymphatic mapping techniques for breast carcinoma has made intraoperative evaluation of sentinel lymph nodes (SLN) attractive, because axillary lymph node dissection can be performed during the initial surgery if the SLN is positive. The optimal technique for rapid SLN assessment has not been determined. Both frozen sectioning and imprint cytology are used for rapid intraoperative SLN evaluation. A retrospective review of the intraoperative imprint cytology results of 133 SLN mapping procedures from 132 breast carcinoma patients was performed. SLN were evaluated intraoperatively by bisecting the lymph node and making imprints of each cut surface. Imprints were stained with hematoxylin and eosin (H&E) and Diff-Quik. Permanent sections were evaluated with up to four H&E stained levels and cytokeratin immunohistochemistry. Imprint cytology results were compared with final histologic results. Sensitivity and specificity of imprint cytology were 56% and 100%, respectively, producing a 100% positive predictive value and 88% negative predictive value. Imprint cytology was significantly more sensitive for macrometastasis than micrometastasis 87% versus 22% (P = 0.00007). Of 13 total false negatives, 11 were found to be due to sampling error and 2 due to errors in intraoperative interpretation. Both intraoperative interpretation errors involved a diagnosis of lobular breast carcinoma. The sensitivity and specificity of imprint cytology are similar to that of frozen section evaluation. Imprint cytology is therefore a viable alternative to frozen sectioning when intraoperative evaluation is required. If SLN micrometastasis is used to determine the need for further lymphadenectomy, more sensitive intraoperative methods will be needed to avoid a second operation.

Self-localization of wireless sensor networks using self-organizing maps

NASA Astrophysics Data System (ADS)

Ertin, Emre; Priddy, Kevin L.

2005-03-01

Recently there has been a renewed interest in the notion of deploying large numbers of networked sensors for applications ranging from environmental monitoring to surveillance. In a typical scenario a number of sensors are distributed in a region of interest. Each sensor is equipped with sensing, processing and communication capabilities. The information gathered from the sensors can be used to detect, track and classify objects of interest. For a number of locations the sensors location is crucial in interpreting the data collected from those sensors. Scalability requirements dictate sensor nodes that are inexpensive devices without a dedicated localization hardware such as GPS. Therefore the network has to rely on information collected within the network to self-localize. In the literature a number of algorithms has been proposed for network localization which uses measurements informative of range, angle, proximity between nodes. Recent work by Patwari and Hero relies on sensor data without explicit range estimates. The assumption is that the correlation structure in the data is a monotone function of the intersensor distances. In this paper we propose a new method based on unsupervised learning techniques to extract location information from the sensor data itself. We consider a grid consisting of virtual nodes and try to fit grid in the actual sensor network data using the method of self organizing maps. Then known sensor network geometry can be used to rotate and scale the grid to a global coordinate system. Finally, we illustrate how the virtual nodes location information can be used to track a target.

PDB to AMPL Conversion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anna Johnston, SNL 9215

2002-09-01

PDB to AMPL Conversion was written to convert protein data base files to AMPL files. The protein data bases on the internet contain a wealth of information about the structue and makeup of proteins. Each file contains information derived by one or more experiments and contains information on how the experiment waw performed, the amino acid building blocks of each chain, and often the three-dimensional structure of the protein extracted from the experiments. The way a protein folds determines much about its function. Thus, studying the three-dimensional structure of the protein is of great interest. Analysing the contact maps ismore » one way to examine the structure. A contact map is a graph which has a linear back bone of amino acids for nodes (i.e., adjacent amino acids are always connected) and vertices between non-adjacent nodes if they are close enough to be considered in contact. If the graphs are similar then the folds of the protein and their function should also be similar. This software extracts the contact maps from a protein data base file and puts in into AMPL data format. This format is designed for use in AMPL, a programming language for simplifying linear programming formulations.« less

Extraction of Intraseasonal Phases of the East Asia Summer Monsoon using Self Organizing Maps and their ENSO effects

NASA Astrophysics Data System (ADS)

Chu, J.; Ha, K.; Hameed, S. N.

2011-12-01

We advance the hypothesis that regional characteristics of the East Asian Summer Monsoon (EASM) result from the presence of non-linear coupled features that modulate the seasonal circulation and rainfall at the intraseasonal timescale. To examine this hypothesis, we undertake the analysis of daily EASM variability using a non-linear multivariate data classifying algorithm known as Self Organizing Maps (SOM). SOM is used to locate archetypal circulation states present in a circulation state vector composed of important indices representing subtropical high pressure regions, the lower and upper level wind vectors and vertical and horizontal shear. These so-called nodes on the SOM identify prominent modes of temporal variations across the region Based on an analysis of the various SOM nodes, we identify 4 major intraseasonal phases of the EASM that are located at the far corners of the SOM. The first node describes a circulation state corresponding to weak tropical and subtropical pressure systems, weakened monsoonal winds, and cyclonic upper level vorticity. This mode that is related with large rainfall anomalies in South East China and Southern Japan occurs a few weeks prior to the onset of Changma rains in Korea. Based on its various characteristics, we identify it is as the Meiyu-Baiu phase. At the diagonally opposite corner from the node representing the Meiyu-Baiu phase, the circulation vector is its mirror image. Copious rains occur over Korea during this phase, which we term the post-Changma phase. The third node selected for this analysis represents the Changma-proper over Korea and occurs with a distinct circulation state corresponding to strengthened subtropical high, monsoonal winds and anticyclonic upper level vorticity to the southeast of Korea. The fourth node is diagonally opposite to this one and features a mirror image of the circulation vector. As Korea experiences a dry-spell associated with this SOM node, we refer to it as the dry-spell phase. We further demonstrate that a strong modulation of the Changma and dry-spell phases on the interannual timescales occurs during El Nino and La Nina years. Our results imply that the key to the predictability of the EASM on interannual timescales may lie with the analysis and exploitation of its non-linear characteristics.

The biodistribution of gold nanoparticles designed for renal clearance

NASA Astrophysics Data System (ADS)

Alric, Christophe; Miladi, Imen; Kryza, David; Taleb, Jacqueline; Lux, François; Bazzi, Rana; Billotey, Claire; Janier, Marc; Perriat, Pascal; Roux, Stéphane; Tillement, Olivier

2013-06-01

Owing to their tunable optical properties and their high absorption cross-section of X- and γ-ray, gold nanostructures appear as promising agents for remotely controlled therapy. Since the efficiency of cancer therapy is not limited to the eradication of the tumour but rests also on the sparing of healthy tissue, a biodistribution study is required in order to determine whether the behaviour of the nanoparticles after intravenous injection is safe (no accumulation in healthy tissue, no uptake by phagocytic cell-rich organs (liver, spleen) and renal clearance). The biodistribution of Au@DTDTPA nanoparticles which are composed of a gold core and a DTDTPA (dithiolated polyaminocarboxylate) shell can be established by X-ray imaging (owing to the X-ray absorption of the gold core) and by magnetic resonance imaging (MRI) since the DTDTPA shell was designed for the immobilization of paramagnetic gadolinium ions. However scintigraphy appears better suited for a biodistribution study owing to a great sensitivity. The successful immobilization of radioelements (99mTc, 111In) in the DTDTPA shell, instead of gadolinium ions, renders possible the follow up of Au@DTDTPA by scintigraphy which showed that Au@DTDTPA nanoparticles exhibit a safe behaviour after intravenous injection to healthy rats.Owing to their tunable optical properties and their high absorption cross-section of X- and γ-ray, gold nanostructures appear as promising agents for remotely controlled therapy. Since the efficiency of cancer therapy is not limited to the eradication of the tumour but rests also on the sparing of healthy tissue, a biodistribution study is required in order to determine whether the behaviour of the nanoparticles after intravenous injection is safe (no accumulation in healthy tissue, no uptake by phagocytic cell-rich organs (liver, spleen) and renal clearance). The biodistribution of Au@DTDTPA nanoparticles which are composed of a gold core and a DTDTPA (dithiolated polyaminocarboxylate) shell can be established by X-ray imaging (owing to the X-ray absorption of the gold core) and by magnetic resonance imaging (MRI) since the DTDTPA shell was designed for the immobilization of paramagnetic gadolinium ions. However scintigraphy appears better suited for a biodistribution study owing to a great sensitivity. The successful immobilization of radioelements (99mTc, 111In) in the DTDTPA shell, instead of gadolinium ions, renders possible the follow up of Au@DTDTPA by scintigraphy which showed that Au@DTDTPA nanoparticles exhibit a safe behaviour after intravenous injection to healthy rats. Electronic supplementary information (ESI) available: Planar scintigraphy image. See DOI: 10.1039/c3nr00012e

Comparison of Node-Centered and Cell-Centered Unstructured Finite-Volume Discretizations: Inviscid Fluxes

NASA Technical Reports Server (NTRS)

Diskin, Boris; Thomas, James L.

2010-01-01

Cell-centered and node-centered approaches have been compared for unstructured finite-volume discretization of inviscid fluxes. The grids range from regular grids to irregular grids, including mixed-element grids and grids with random perturbations of nodes. Accuracy, complexity, and convergence rates of defect-correction iterations are studied for eight nominally second-order accurate schemes: two node-centered schemes with weighted and unweighted least-squares (LSQ) methods for gradient reconstruction and six cell-centered schemes two node-averaging with and without clipping and four schemes that employ different stencils for LSQ gradient reconstruction. The cell-centered nearest-neighbor (CC-NN) scheme has the lowest complexity; a version of the scheme that involves smart augmentation of the LSQ stencil (CC-SA) has only marginal complexity increase. All other schemes have larger complexity; complexity of node-centered (NC) schemes are somewhat lower than complexity of cell-centered node-averaging (CC-NA) and full-augmentation (CC-FA) schemes. On highly anisotropic grids typical of those encountered in grid adaptation, discretization errors of five of the six cell-centered schemes converge with second order on all tested grids; the CC-NA scheme with clipping degrades solution accuracy to first order. The NC schemes converge with second order on regular and/or triangular grids and with first order on perturbed quadrilaterals and mixed-element grids. All schemes may produce large relative errors in gradient reconstruction on grids with perturbed nodes. Defect-correction iterations for schemes employing weighted least-square gradient reconstruction diverge on perturbed stretched grids. Overall, the CC-NN and CC-SA schemes offer the best options of the lowest complexity and secondorder discretization errors. On anisotropic grids over a curved body typical of turbulent flow simulations, the discretization errors converge with second order and are small for the CC-NN, CC-SA, and CC-FA schemes on all grids and for NC schemes on triangular grids; the discretization errors of the CC-NA scheme without clipping do not converge on irregular grids. Accurate gradient reconstruction can be achieved by introducing a local approximate mapping; without approximate mapping, only the NC scheme with weighted LSQ method provides accurate gradients. Defect correction iterations for the CC-NA scheme without clipping diverge; for the NC scheme with weighted LSQ method, the iterations either diverge or converge very slowly. The best option in curved geometries is the CC-SA scheme that offers low complexity, second-order discretization errors, and fast convergence.

High-level Closed-loop Fusion and Decision Making with INFORM Lab

DTIC Science & Technology

2011-06-01

gling fr eighte r zodiac Toolbox / Library node. The output of the editor is an XML file that contains all the information needed to run the ...surveillance. It uses two land-based zodiacs to offload the illegal immigrants, by making multiple trips to/from the freighter to ferry persons to the ...mapped in Figure 9. Figure 9 Map of Non-Cooperative Search Vignette The freighter and zodiacs will attempt various elusive manoeuvres depending on

Circuit-Switched Memory Access in Photonic Interconnection Networks for High-Performance Embedded Computing

DTIC Science & Technology

2010-07-22

dependent , providing a natural bandwidth match between compute cores and the memory subsystem. • High Bandwidth Dcnsity. Waveguides crossing the chip...simulate this memory access architecture on a 2S6-core chip with a concentrated 64-node network lIsing detailed traces of high-performance embedded...memory modulcs, wc placc memory access poi nts (MAPs) around the pcriphery of the chip connected to thc nctwork. These MAPs, shown in Figure 4, contain

Parameter-dependent behaviour of periodic channels in a locus of boundary crisis

NASA Astrophysics Data System (ADS)

Rankin, James; Osinga, Hinke M.

2017-06-01

A boundary crisis occurs when a chaotic attractor outgrows its basin of attraction and suddenly disappears. As previously reported, the locus of a boundary crisis is organised by homo- or heteroclinic tangencies between the stable and unstable manifolds of saddle periodic orbits. In two parameters, such tangencies lead to curves, but the locus of boundary crisis along those curves exhibits gaps or channels, in which other non-chaotic attractors persist. These attractors are stable periodic orbits which themselves can undergo a cascade of period-doubling bifurcations culminating in multi-component chaotic attractors. The canonical diffeomorphic two-dimensional Hénon map exhibits such periodic channels, which are structured in a particular ordered way: each channel is bounded on one side by a saddle-node bifurcation and on the other by a period-doubling cascade to chaos; furthermore, all channels seem to have the same orientation, with the saddle-node bifurcation always on the same side. We investigate the locus of boundary crisis in the Ikeda map, which models the dynamics of energy levels in a laser ring cavity. We find that the Ikeda map features periodic channels with a richer and more general organisation than for the Hénon map. Using numerical continuation, we investigate how the periodic channels depend on a third parameter and characterise how they split into multiple channels with different properties.

The seventh tumour-node-metastasis staging system for lung cancer: Sequel or prequel?

PubMed

van Meerbeeck, Jan P; Janssens, Annelies

2013-09-01

Anatomical cancer extent is an important predictor of prognosis and determines treatment choices. In non-small-cell lung cancer (NSCLC) the tumour-node-metastasis (TNM) classification developed by Pierre Denoix replaced in 1968 the Veterans Administration Lung cancer Group (VALG) classification, which was still in use for small-cell lung cancer (SCLC). Clifton Mountain suggested several improvements based on a database of mostly surgically treated United States (US) patients from a limited number of centres. This database was pivotal for a uniform reporting of lung cancer extent by the American Joint Committee of Cancer (AJCC) and the International Union against Cancer (IUCC), but it suffered increasingly from obsolete diagnostic and staging procedures and did not reflect new treatment modalities. Moreover, its findings were not externally validated in large Japanese and European databases, resulting in persisting controversies which could not be solved with the available database. The use of different mediastinal lymph-node maps in Japan, the (US) and Europe facilitated neither the exchange nor the comparison of treatment results. Peter Goldstraw, a United Kingdom (UK) thoracic surgeon, started the process of updating the sixth version in 1996 and brought it to a good end 10 years later. His goals were to improve the TNM system in lung cancer by addressing the ongoing controversies, to validate the modifications and additional descriptors, to validate the TNM for use in staging SCLC and carcinoid tumours, to propose a new uniform lymph-node map and to investigate the prognostic value of non-anatomical factors. A staging committee was formed within the International Association for the Study of Lung Cancer (IASLC) - which supervised the collection of the retrospective data from >100,000 patients with lung cancer - treated throughout the world between 1990 and 2000, analyse them with the help of solid statistics and validate externally with the Surveillance, Epidemiology and End Results (SEER) database. The ten modifications and the mediastinal lymph-node map - which were proposed in 2007 and adopted by the AJCC and IUCC in their respective seventh revision of the TNM system - were implemented as of 2010 and were rapidly adopted by the thoracic oncology community and cancer registries. As expected, not all controversies could be fully addressed, and the need for a prospective data set containing more granular information was felt early on. This data set of 25,000 consecutive incident cases will form the base for the eighth revision in 2017 and is currently being collected. Other threats are the role of stage migration and the increasing number of biological factors interfering with disease extent for prognostication. The latter issue will be addressed by the creation of a prognostic index, including several prognostic factors, of which stage will be one. For the time being, the seventh TNM classification is considered the gold standard for the description of disease extent, initial treatment allocation and the reporting of treatment results. The uniform use of the TNM descriptors and the lymph-node map by all involved in lung cancer care is to be considered a process indicator of quality.

New surface radiolabeling schemes of super paramagnetic iron oxide nanoparticles (SPIONs) for biodistribution studies.

PubMed

Nallathamby, Prakash D; Mortensen, Ninell P; Palko, Heather A; Malfatti, Mike; Smith, Catherine; Sonnett, James; Doktycz, Mitchel J; Gu, Baohua; Roeder, Ryan K; Wang, Wei; Retterer, Scott T

2015-04-21

Nanomaterial based drug delivery systems allow for the independent tuning of the surface chemical and physical properties that affect their biodistribution in vivo and the therapeutic payloads that they are intended to deliver. Additionally, the added therapeutic and diagnostic value of their inherent material properties often provides extra functionality. Iron based nanomaterials with their magnetic properties and easily tailorable surface chemistry are of particular interest as model systems. In this study the core radius of the iron oxide nanoparticles (NPs) was 14.08 ± 3.92 nm while the hydrodynamic radius of the NPs, as determined by Dynamic Light Scattering (DLS), was between 90-110 nm. In this study, different approaches were explored to create radiolabeled NPs that are stable in solution. The NPs were functionalized with polycarboxylate or polyamine surface functional groups. Polycarboxylate functionalized NPs had a zeta potential of -35 mV and polyamine functionalized NPs had a zeta potential of +40 mV. The polycarboxylate functionalized NPs were chosen for in vivo biodistribution studies and hence were radiolabeled with (14)C, with a final activity of 0.097 nCi mg(-1) of NPs. In chronic studies, the biodistribution profile is tracked using low level radiolabeled proxies of the nanoparticles of interest. Conventionally, these radiolabeled proxies are chemically similar but not chemically identical to the non-radiolabeled NPs of interest. This study is novel as different approaches were explored to create radiolabeled NPs that are stable, possess a hydrodynamic radius of <100 nm and most importantly they exhibit an identical surface chemical functionality as their non-radiolabeled counterparts. Identical chemical functionality of the radiolabeled probes to the non-radiolabeled probes was an important consideration to generate statistically similar biodistribution data sets using multiple imaging and detection techniques. The radiolabeling approach described here is applicable to the synthesis of a large class of nanomaterials with multiple core and surface functionalities. This work combined with the biodistribution data suggests that the radiolabeling schemes carried out in this study have broad implications for use in pharmacokinetic studies for a variety of nanomaterials.

New surface radiolabeling schemes of super paramagnetic iron oxide nanoparticles (SPIONs) for biodistribution studies†

PubMed Central

Nallathamby, Prakash D.; Mortensen, Ninell P.; Palko, Heather A.; Malfatti, Mike; Smith, Catherine; Sonnett, James; Doktycz, Mitchel J.; Gu, Baohua; Roeder, Ryan K.; Wang, Wei; Retterer, Scott T.

2016-01-01

Nanomaterial based drug delivery systems allow for the independent tuning of the surface chemical and physical properties that affect their biodistribution in vivo and the therapeutic payloads that they are intended to deliver. Additionally, the added therapeutic and diagnostic value of their inherent material properties often provides extra functionality. Iron based nanomaterials with their magnetic properties and easily tailorable surface chemistry are of particular interest as model systems. In this study the core radius of the iron oxide nanoparticles (NPs) was 14.08 ± 3.92 nm while the hydrodynamic radius of the NPs, as determined by Dynamic Light Scattering (DLS), was between 90–110 nm. In this study, different approaches were explored to create radiolabeled NPs that are stable in solution. The NPs were functionalized with polycarboxylate or polyamine surface functional groups. Polycarboxylate functionalized NPs had a zeta potential of –35 mV and polyamine functionalized NPs had a zeta potential of +40 mV. The polycarboxylate functionalized NPs were chosen for in vivo biodistribution studies and hence were radiolabeled with 14C, with a final activity of 0.097 nCi mg–1 of NPs. In chronic studies, the biodistribution profile is tracked using low-level radiolabeled proxies of the nanoparticles of interest. Conventionally, these radiolabeled proxies are chemically similar but not chemically identical to the non-radiolabeled NPs of interest. This study is novel as different approaches were explored to create radiolabeled NPs that are stable, possess a hydrodynamic radius of <100 nm and most importantly they exhibit an identical surface chemical functionality as their non-radiolabeled counterparts. Identical chemical functionality of the radiolabeled probes to the non-radiolabeled probes was an important consideration to generate statistically similar biodistribution data sets using multiple imaging and detection techniques. The radiolabeling approach described here is applicable to the synthesis of a large class of nanomaterials with multiple core and surface functionalities. This work combined with the biodistribution data suggests that the radiolabeling schemes carried out in this study have broad implications for use in pharmacokinetic studies for a variety of nanomaterials. PMID:25790032

New Surface Radiolabeling Schemes of Super Paramagnetic Iron Oxide Nanoparticles (SPIONs) for Biodistribution Studies

DOE PAGES

Nallathamby, Prakash D.; Mortensen, Ninell P.; Palko, Heather A.; ...

2015-03-02

Nanomaterial based drug delivery systems allow for the independent tuning of the surface chemical and physical properties that affect their biodistribution in vivo and the therapeutic payloads that they are intended to deliver. Additionally, the added therapeutic and diagnostic value of their inherent material properties often provides extra functionality. Iron based nanomaterials with their magnetic properties and 10 easily tailorable surface chemistry are of particular interest as model systems. In this study the core radius of the iron oxide nanoparticles (NPs) was 14.08 3.92 nm while the hydrodynamic radius of the NPs, as determined by Dynamic Light Scattering (DLS), wasmore » between 90 110 nm. In this study, different approaches were explored to create radiolabeled NPs that are stable in solution. The NPs were functionalized with polycarboxylate or polyamine surface functional groups. Polycarboxylate 15 functionalized NPs had a zeta potential of -35 mV and polyamine functionalized NPs had a zeta potential of +40 mV. The polycarboxylate functionalized NPs were chosen for in vivo biodistribution studies and hence were radiolabeled with 14C, with a final activity of 0.097 nCi/mg -1 of NPs. In chronic studies, the biodistribution profile is tracked using low level radiolabeled proxies of the nanoparticles of interest. Conventionally, these radiolabeled proxies are chemically similar but not chemically identical to the non-20 radiolabeled NPs of interest. This study is novel as different approaches were explored to create radiolabeled NPs that are stable, possess a hydrodynamic radius of <100 nm and most importantly they exhibit an identical surface chemical functionality as their non-radiolabeled counterparts. Identical chemical functionality of the radiolabeled probes to the non-radiolabeled probes was an important consideration to generate statistically similar biodistribution data sets using multiple imaging and 25 detection techniques. The radiolabeling approach described here is applicable to the synthesis of a large class of nanomaterials with multiple core and surface functionalities. This work combined with the biodistribution data suggests that the radiolabeling schemes carried out in this study have broad implications for use in pharmacokinetic studies for a variety of nanomaterials.« less

Ultrasound-guided photoacoustic imaging of lymph nodes with biocompatible gold nanoparticles as a novel contrast agent (Conference Presentation)

NASA Astrophysics Data System (ADS)

Sun, In-Cheol; Dumani, Diego; Emelianov, Stanislav Y.

2017-02-01

A key step in staging cancer is the diagnosis of metastasis that spreads through lymphatic system. For this reason, researchers develop various methods of sentinel lymph node mapping that often use a radioactive tracer. This study introduces a safe, cost-effective, high-resolution, high-sensitivity, and real-time method of visualizing the sentinel lymph node: ultrasound-guided photoacoustic (US/PA) imaging augmented by a contrast agent. In this work, we use clearable gold nanoparticles covered by a biocompatible polymer (glycol chitosan) to enhance cellular uptake by macrophages abundant in lymph nodes. We incubate macrophages with glycol-chitosan-coated gold nanoparticles (0.05 mg Au/ml), and then fix them with paraformaldehyde solution for an analysis of in vitro dark-field microscopy and cell phantom. The analysis shows enhanced cellular uptake of nanoparticles by macrophages and strong photoacoustic signal from labeled cells in tissue-mimicking cell phantoms consisting gelatin solution (6 %) with silica gel (25 μm, 0.3%) and fixed macrophages (13 X 105 cells). The in-vivo US/PA imaging of cervical lymph nodes in healthy mice (nu/nu, female, 5 weeks) indicates a strong photoacoustic signal from a lymph node 10 minutes post-injection (2.5 mg Au/ml, 80 μl). The signal intensity and the nanoparticle-labeled volume of tissue within the lymph node continues to increase until 4 h post-injection. Histological analysis further confirms the accumulation of gold nanoparticles within the lymph nodes. This work suggests the feasibility of molecular/cellular US/PA imaging with biocompatible gold nanoparticles as a photoacoustic contrast agent in the diagnosis of lymph-node-related diseases.

Optical differentiation between malignant and benign lymphadenopathy by grey scale texture analysis of endobronchial ultrasound convex probe images.

PubMed

Nguyen, Phan; Bashirzadeh, Farzad; Hundloe, Justin; Salvado, Olivier; Dowson, Nicholas; Ware, Robert; Masters, Ian Brent; Bhatt, Manoj; Kumar, Aravind Ravi; Fielding, David

2012-03-01

Morphologic and sonographic features of endobronchial ultrasound (EBUS) convex probe images are helpful in predicting metastatic lymph nodes. Grey scale texture analysis is a well-established methodology that has been applied to ultrasound images in other fields of medicine. The aim of this study was to determine if this methodology could differentiate between benign and malignant lymphadenopathy of EBUS images. Lymph nodes from digital images of EBUS procedures were manually mapped to obtain a region of interest and were analyzed in a prediction set. The regions of interest were analyzed for the following grey scale texture features in MATLAB (version 7.8.0.347 [R2009a]): mean pixel value, difference between maximal and minimal pixel value, SEM pixel value, entropy, correlation, energy, and homogeneity. Significant grey scale texture features were used to assess a validation set compared with fluoro-D-glucose (FDG)-PET-CT scan findings where available. Fifty-two malignant nodes and 48 benign nodes were in the prediction set. Malignant nodes had a greater difference in the maximal and minimal pixel values, SEM pixel value, entropy, and correlation, and a lower energy (P < .0001 for all values). Fifty-one lymph nodes were in the validation set; 44 of 51 (86.3%) were classified correctly. Eighteen of these lymph nodes also had FDG-PET-CT scan assessment, which correctly classified 14 of 18 nodes (77.8%), compared with grey scale texture analysis, which correctly classified 16 of 18 nodes (88.9%). Grey scale texture analysis of EBUS convex probe images can be used to differentiate malignant and benign lymphadenopathy. Preliminary results are comparable to FDG-PET-CT scan.

An Ad-hoc Satellite Network to Measure Filamentary Current Structures in the Auroral Zone

NASA Astrophysics Data System (ADS)

Nabong, C.; Fritz, T. A.; Semeter, J. L.

2014-12-01

An ad-hoc cubesat-based satellite network project known as ANDESITE is under development at Boston University. It aims to develop a dense constellation of easy-to-use, rapidly-deployable low-cost wireless sensor nodes in space. The objectives of the project are threefold: 1) Demonstrate viability of satellite based sensor networks by deploying an 8-node miniature sensor network to study the filamentation of the field aligned currents in the auroral zones of the Earth's magnetosphere. 2) Test the scalability of proposed protocols, including localization techniques, tracking, data aggregation, and routing, for a 3 dimensional wireless sensor network using a "flock" of nodes. 3) Construct a 6U Cube-sat running the Android OS as an integrated constellation manager, data mule and sensor node deplorer. This small network of sensor nodes will resolve current densities at different spatial resolutions in the near-Earth magnetosphere using measurements from magnetometers with 1-nT sensitivities and 0.2 nT/√Hz self-noise. Mapping of these currents will provide new constraints for models of auroral particle acceleration, wave-particle interactions, ionospheric destabilization, and other kinetic processes operating in the low-beta plasma of the near Earth magnetosphere.

Detecting and Preventing Sybil Attacks in Wireless Sensor Networks Using Message Authentication and Passing Method.

PubMed

Dhamodharan, Udaya Suriya Raj Kumar; Vayanaperumal, Rajamani

2015-01-01

Wireless sensor networks are highly indispensable for securing network protection. Highly critical attacks of various kinds have been documented in wireless sensor network till now by many researchers. The Sybil attack is a massive destructive attack against the sensor network where numerous genuine identities with forged identities are used for getting an illegal entry into a network. Discerning the Sybil attack, sinkhole, and wormhole attack while multicasting is a tremendous job in wireless sensor network. Basically a Sybil attack means a node which pretends its identity to other nodes. Communication to an illegal node results in data loss and becomes dangerous in the network. The existing method Random Password Comparison has only a scheme which just verifies the node identities by analyzing the neighbors. A survey was done on a Sybil attack with the objective of resolving this problem. The survey has proposed a combined CAM-PVM (compare and match-position verification method) with MAP (message authentication and passing) for detecting, eliminating, and eventually preventing the entry of Sybil nodes in the network. We propose a scheme of assuring security for wireless sensor network, to deal with attacks of these kinds in unicasting and multicasting.

Detecting and Preventing Sybil Attacks in Wireless Sensor Networks Using Message Authentication and Passing Method

PubMed Central

Dhamodharan, Udaya Suriya Raj Kumar; Vayanaperumal, Rajamani

2015-01-01

Wireless sensor networks are highly indispensable for securing network protection. Highly critical attacks of various kinds have been documented in wireless sensor network till now by many researchers. The Sybil attack is a massive destructive attack against the sensor network where numerous genuine identities with forged identities are used for getting an illegal entry into a network. Discerning the Sybil attack, sinkhole, and wormhole attack while multicasting is a tremendous job in wireless sensor network. Basically a Sybil attack means a node which pretends its identity to other nodes. Communication to an illegal node results in data loss and becomes dangerous in the network. The existing method Random Password Comparison has only a scheme which just verifies the node identities by analyzing the neighbors. A survey was done on a Sybil attack with the objective of resolving this problem. The survey has proposed a combined CAM-PVM (compare and match-position verification method) with MAP (message authentication and passing) for detecting, eliminating, and eventually preventing the entry of Sybil nodes in the network. We propose a scheme of assuring security for wireless sensor network, to deal with attacks of these kinds in unicasting and multicasting. PMID:26236773

The Lymphatic Anatomy of the Breast and its Implications for Sentinel Lymph Node Biopsy: A Human Cadaver Study

PubMed Central

Pan, Wei-Ren; Mann, G. Bruce; Taylor, G. Ian

2007-01-01

Background Current understanding of the lymphatic system of the breast is derived mainly from the work of the anatomist Sappey in the 1850s, with many observations made during the development and introduction of breast lymphatic mapping and sentinel node biopsy contributing to our knowledge. Methods Twenty four breasts in 14 fresh human cadavers (5 male, 9 female) were studied. Lymph vessels were identified with hydrogen peroxide and injected with a lead oxide mixture and radiographed. The specimens were cross sectioned and radiographed to provide three dimensional images. Lymph (collecting) vessels were traced from the periphery to the first-tier lymph node. Results Lymph collecting vessels were found evenly spaced at the periphery of the anterior upper torso draining radially into the axillary lymph nodes. As they reached the breast some passed over and some through the breast parenchyma, as revealed in the cross-section studies. The pathways showed no significant difference between male and female specimens. We found also perforating lymph vessels that coursed beside the branches of the internal mammary vessels, draining into the ipsilateral internal mammary lymphatics. In some studies one sentinel node in the axilla drained almost the entire breast. In most more than one sentinel node was represented. Conclusion These anatomical findings are discordant with our current knowledge based on previous studies and demand closer examination by clinicians. These anatomical studies may help explain the percentage of false-negative sentinel node biopsy studies and suggest the peritumoral injection site for accurate sentinel lymph node detection. PMID:18043970

Impact of Indocyanine Green for Sentinel Lymph Node Mapping in Early Stage Endometrial and Cervical Cancer: Comparison with Conventional Radiotracer (99m)Tc and/or Blue Dye.

PubMed

Buda, Alessandro; Crivellaro, Cinzia; Elisei, Federica; Di Martino, Giampaolo; Guerra, Luca; De Ponti, Elena; Cuzzocrea, Marco; Giuliani, Daniela; Sina, Federica; Magni, Sonia; Landoni, Claudio; Milani, Rodolfo

2016-07-01

To compare the detection rate (DR) and bilateral optimal mapping (OM) of sentinel lymph nodes (SLNs) in women with endometrial and cervical cancer using indocyanine green (ICG) versus the standard technetium-99m radiocolloid ((99m)Tc) radiotracer plus methylene or isosulfan blue, or blue dye alone. From October 2010 to May 2015, 163 women with stage I endometrial or cervical cancer (118 endometrial and 45 cervical cancer) underwent SLN mapping with (99m)Tc with blue dye, blue dye alone, or ICG. DR and bilateral OM of ICG were compared respectively with the results obtained using the standard (99m)Tc radiotracer with blue dye, or blue dye alone. SLN mapping with (99m)Tc radiotracer with blue dye was performed on 77 of 163 women, 38 with blue dye only and 48 with ICG. The overall DR of SLN mapping was 97, 89, and 100 % for (99m)Tc with blue dye, blue dye alone, and ICG, respectively. The bilateral OM rate for ICG was 85 %-significantly higher than the 58 % obtained with (99m)Tc with blue dye (p = 0.003) and the 54 % for blue dye (p = 0.001). Thirty-one women (19 %) had positive SLNs. Sensitivity and negative predictive value of SLN were 100 % for all techniques. SLNs mapping using ICG demonstrated higher DR compared to other modalities. In addition, ICG was significantly superior to (99m)Tc with blue dye in terms of bilateral OM in women with early stage endometrial and cervical cancer. The higher number of bilateral OM may consequently reduce the overall number of complete lymphadenectomies, reducing the duration and additional costs of surgical treatment.

A Reading Attempt of the Urban Memory of Eskisehir Osmangazi University Meselik Campus via Cognitive Mapping

NASA Astrophysics Data System (ADS)

Alptekin, Orkun

2017-10-01

University campuses have a small city view containing basic city functions such as work, accommodation, rest and transportation. They are spaces of social life that occupy large areas, have population density and different activities, change and grow with the cities they live in, and memorize the past accumulations. In this context, it is necessary for campuses to form and protect their own memories like cities. Campus memory is the ability of individuals to keep, maintain and - when necessary- reveal the experiences, sensations, comprehensions gathered from physical environment. "Cognitive mapping" is used to reveal the physical and emotional relationship that individuals make with the city and the individual-city interaction. Cognitive maps are created graphically using verbal and geometric items on paper by remembering these coded urban images. In this study, to determine the urban images belonging to Eskisehir Osmangazi University Meselik Campus, architecture students who have a short period experience of the campus were asked to note the areas they interact with the campus on the cognitive map. Campus memory items are identified by analysing the cognitive maps of the individuals who experienced the campus. In the direction of the obtained data, the campus area was re-read with five basic elements of Lynch: paths, districts, edges, nodes, and landmarks. As a result of these analyses, it is seen that religious structure, which is a large symbolic structure, located next to the main entrance in the settlement and health care facilities defined as landmarks are located in the memory of most of the individuals. Then, paths, nodes, districts, edges and educational buildings are listed respectively in cognitive maps.

Brain tumor magnetic targeting and biodistribution of superparamagnetic iron oxide nanoparticles linked with 70-kDa heat shock protein study by nonlinear longitudinal response

NASA Astrophysics Data System (ADS)

Shevtsov, Maxim A.; Nikolaev, Boris P.; Ryzhov, Vyacheslav A.; Yakovleva, Ludmila Y.; Dobrodumov, Anatolii V.; Marchenko, Yaroslav Y.; Margulis, Boris A.; Pitkin, Emil; Guzhova, Irina V.

2015-08-01

Brain tumor targeting efficiency and biodistribution of the superparamagnetic nanoparticles conjugated with heat shock protein Hsp70 (SPION-Hsp70) were evaluated in experimental glioma model. Synthesized conjugates were characterized using the method of longitudinal nonlinear response of magnetic nanoparticles to a weak ac magnetic field with measurements of second harmonic of magnetization (NLR-M2). Cellular interaction of magnetic conjugates was analyzed in 9L glioma cell culture. The biodistribution of the nanoparticles and their accumulation in tumors was assessed by the latter approach as well. The efficacy of Hsp70-conjugates for contrast enhancement in the orthotopic model of 9L glioma was assessed by MR imaging (11 T). Magnetic nanoparticles conjugated with Hsp70 had the relaxivity properties of the MR-negative contrast agents. Morphological observation and cell viability test demonstrated good biocompatibility of Hsp70-conjugates. Analysis of the T2-weighted MR scans in tumor-bearing rats demonstrated the high efficacy of Hsp70-conjugates in contrast enhancement of the glioma in comparison to non-conjugated nanoparticles. High contrast enhancement of the glioma was provided by the accumulation of the SPION-Hsp70 particles in the glioma tissue (as shown by the histological assay). Biodistribution analysis by NLR-M2 measurements evidenced the many-fold increase (~40) in the tumor-to-normal brain uptake ratio in the Hsp70-conjugates treated animals. Biodistribution pattern of Hsp70-decorated nanoparticles differed from that of non-conjugated SPIONs. Coating of the magnetic nanoparticles with Hsp70 protein enhances the tumor-targeting ability of the conjugates that could be applied in the MR imaging of the malignant brain tumors.

Preclinical good laboratory practice-compliant safety study to evaluate biodistribution and tumorigenicity of a cartilage advanced therapy medicinal product (ATMP).

PubMed

Zscharnack, Matthias; Krause, Christoph; Aust, Gabriela; Thümmler, Christian; Peinemann, Frank; Keller, Thomas; Smink, Jeske J; Holland, Heidrun; Somerson, Jeremy S; Knauer, Jens; Schulz, Ronny M; Lehmann, Jörg

2015-05-20

The clinical development of advanced therapy medicinal products (ATMPs), a new class of drugs, requires initial safety studies that deviate from standard non-clinical safety protocols. The study provides a strategy to address the safety aspects of biodistribution and tumorigenicity of ATMPs under good laboratory practice (GLP) conditions avoiding cell product manipulation. Moreover, the strategy was applied on a human ATMP for cartilage repair. The testing strategy addresses biodistribution and tumorigenicity using a multi-step analysis without any cell manipulation to exclude changes of test item characteristics. As a safeguard measurement for meeting regulatory expectations, the project design and goals were discussed continuously with the regulatory authority using a staggered scientific advice concept. Subsequently, the strategy was applied to co.don chondrosphere® (huChon spheroid), a tissue-engineered matrix-free ATMP of human normal chondrocytes. In both the biodistribution and tumorigenicity studies, huChon spheroids were implanted subcutaneously into 40 immunodeficient mice. Biodistribution was studied 1 month after implantation. A skin disc containing the huChon spheroid, two surrounding skin rings and selected organs were analyzed by validated, gender-specific, highly-sensitive triplex qPCR and by immunohistochemistry (IHC). No human DNA was detected in distant skin rings and analyzed organs. IHC revealed no direct or indirect indications of cell migration. Tumorigenicity was assessed 6 months after huChon spheroid implantation by palpation, macroscopic inspection, histology and IHC. No mice from the huChon spheroid group developed a tumor at the implantation site. In two mice, benign tumors were detected that were negative for HLA-ABC, suggesting that they were of spontaneous murine origin. In summary, the presented strategy using a multi-step analysis was confirmed to be suitable for safety studies of ATMPs.

90Yttrium Ibritumomab Tiuxetan Therapy in Allogeneic Transplantation in B-cell Lymphoma with Extensive Marrow involvement and Chronic Lymphocytic Leukemia: Utility of Pre-transplantation Biodistribution

PubMed Central

Matesan, Manuela; Rajendran, Joseph; Press, Oliver W.; Maloney, David G.; Storb, Rainer F.; Cassaday, Ryan D.; Pagel, John M.; Oliveira, George; Gopal, Ajay K.

2014-01-01

Biodistribution data to-date using 111In- ibritumomab tiuxetan has been initially obtained in patients with <25% lymphomatous bone marrow involvement and adequate hematopoietic synthetic function. In this article we present the results of an analysis of the biodistribution data obtained from a cohort of patients with extensive bone marrow involvement, baseline cytopenias, and chronic lymphocytic leukemia (CLL). Thirty nine patients with diagnosis of B-cell lymphoma or CLL expressing the CD20 antigen, who had failed at least one prior regimen, and had evidence of persistent disease were included in this analysis, however only 38 of these completed the treatment. Semiquantitative analysis of the biodistribution was performed using regions of interest (ROI) over the liver, lungs, kidneys, spleen and sacrum. The observed interpatient variability including higher liver uptake in 4 patients is discussed. No severe solid organs toxicity was observed at the maximum administered activity of 1184 MBq (32 mCi) 90Yibritumomab tiuxetan. After accounting for differences in marrow involvement, patients with CLL exhibit comparable biodistributions to those with B-NHL. We found that the estimated sacral marrow uptake on 48 hour images in patients with bone marrow involvement may be an indicator of bone marrow involvement. There was no correlation between tumor visualization and response to treatment. These data suggest that the imaging step is not critical when the administered activity is below 1184 MBq (32 mCi). However our analysis confirms that the semiquantitative imaging data can be used to identify patients at risk for liver toxicity when higher doses of 90Y- ibritumomab tiuxetan are used. Patients with CLL can have excellent targeting of disease by 111Inibritumomab tiuxetan, indicating potential efficacy in this patient population. PMID:25076159

Color Doppler Ultrasound and Gamma Imaging of Intratumorally Injected 500 nm Iron-Silica Nanoshells

PubMed Central

Liberman, Alexander; Wu, Zhe; Barback, Christopher V.; Viveros, Robert; Blair, Sarah L.; Ellies, Lesley G.; Vera, David R.; Mattrey, Robert F.; Kummel, Andrew C.; Trogler, William C.

2013-01-01

Perfluoropentane gas filled iron-silica nanoshells have been developed as stationary ultrasound contrast agents for marking tumors to guide surgical resection. It is critical to establish their long term imaging efficacy, as well as biodistribution. This work shows that 500 nm Fe-SiO2 nanoshells can be imaged by color Doppler ultrasound over the course of 10 days in Py8119 tumor bearing mice. The 500 nm non-biodegradable SiO2 and biodegradable Fe-SiO2 nanoshells were functionalized with diethylenetriamine pentaacetic acid (DTPA) ligand and radiolabeled with 111In3+ for biodistribution studies in nu/nu mice. The majority of radioactivity was detected in the liver and kidneys following intravenous (IV) administration of nanoshells to healthy animals. By contrast, after nanoshells were injected intratumorally, most of the radioactivity remained at the injection site; however, some nanoshells escaped into circulation and were distributed similarly as those given intravenously. For intratumoral delivery of nanoshells and IV delivery to healthy animals, little difference was seen between the biodistribution of SiO2 and biodegradable Fe-SiO2 nanoshells. However, when nanoshells were administered IV to tumor bearing mice, a significant increase was observed in liver accumulation of SiO2 nanoshells relative to biodegradable Fe-SiO2 nanoshells. Both SiO2 and Fe-SiO2 nanoshells accumulate passively in proportion to tumor mass, during intravenous delivery of nanoshells. This is the first report of the biodistribution following intratumoral injection of any biodegradable silica particle, as well as the first report demonstrating the utility of DTPA-111In labeling for studying silica nanoparticle biodistributions. PMID:23802554

INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY: Estimating Topology of Discrete Dynamical Networks

NASA Astrophysics Data System (ADS)

Guo, Shu-Juan; Fu, Xin-Chu

2010-07-01

In this paper, by applying Lasalle's invariance principle and some results about the trace of a matrix, we propose a method for estimating the topological structure of a discrete dynamical network based on the dynamical evolution of the network. The network concerned can be directed or undirected, weighted or unweighted, and the local dynamics of each node can be nonidentical. The connections among the nodes can be all unknown or partially known. Finally, two examples, including a Hénon map and a central network, are illustrated to verify the theoretical results.

Predicting the impact of biocorona formation kinetics on interspecies extrapolations of nanoparticle biodistribution modeling.

PubMed

Sahneh, Faryad Darabi; Scoglio, Caterina M; Monteiro-Riviere, Nancy A; Riviere, Jim E

2015-01-01

To assess the impact of biocorona kinetics on expected tissue distribution of nanoparticles (NPs) across species. The potential fate of NPs in vivo is described through a simple and descriptive pharmacokinetic model using rate processes dependent upon basal metabolic rate coupled to dynamics of protein corona. Mismatch of time scales between interspecies allometric scaling and the kinetics of corona formation is potentially a fundamental issue with interspecies extrapolations of NP biodistribution. The impact of corona evolution on NP biodistribution across two species is maximal when corona transition half-life is close to the geometric mean of NP half-lives of the two species. While engineered NPs can successfully reach target cells in rodent models, the results may be different in humans due to the fact that the longer circulation time allows for further biocorona evolution.

(125)I-Tetrazines and Inverse-Electron-Demand Diels-Alder Chemistry: A Convenient Radioiodination Strategy for Biomolecule Labeling, Screening, and Biodistribution Studies.

PubMed

Albu, Silvia A; Al-Karmi, Salma A; Vito, Alyssa; Dzandzi, James P K; Zlitni, Aimen; Beckford-Vera, Denis; Blacker, Megan; Janzen, Nancy; Patel, Ramesh M; Capretta, Alfredo; Valliant, John F

2016-01-20

A convenient method to prepare radioiodinated tetrazines was developed, such that a bioorthogonal inverse electron demand Diels-Alder reaction can be used to label biomolecules with iodine-125 for in vitro screening and in vivo biodistribution studies. The tetrazine was prepared by employing a high-yielding oxidative halo destannylation reaction that concomitantly oxidized the dihydrotetrazine precursor. The product reacts quickly and efficiently with trans-cyclooctene derivatives. Utility was demonstrated through antibody and hormone labeling experiments and by evaluating products using standard analytical methods, in vitro assays, and quantitative biodistribution studies where the latter was performed in direct comparison to Bolton-Hunter and direct iodination methods. The approach described provides a convenient and advantageous alternative to conventional protein iodination methods that can expedite preclinical development and evaluation of biotherapeutics.

A linked GeoData map for enabling information access

USGS Publications Warehouse

Powell, Logan J.; Varanka, Dalia E.

2018-01-10

OverviewThe Geospatial Semantic Web (GSW) is an emerging technology that uses the Internet for more effective knowledge engineering and information extraction. Among the aims of the GSW are to structure the semantic specifications of data to reduce ambiguity and to link those data more efficiently. The data are stored as triples, the basic data unit in graph databases, which are similar to the vector data model of geographic information systems (GIS); that is, a node-edge-node model that forms a graph of semantically related information. The GSW is supported by emerging technologies such as linked geospatial data, described below, that enable it to store and manage geographical data that require new cartographic methods for visualization. This report describes a map that can interact with linked geospatial data using a simulation of a data query approach called the browsable graph to find information that is semantically related to a subject of interest, visualized using the Data Driven Documents (D3) library. Such a semantically enabled map functions as a map knowledge base (MKB) (Varanka and Usery, 2017).A MKB differs from a database in an important way. The central element of a triple, alternatively called the edge or property, is composed of a logic formalization that structures the relation between the first and third parts, the nodes or objects. Node-edge-node represents the graphic form of the triple, and the subject-property-object terms represent the data structure. Object classes connect to build a federated graph, similar to a network in visual form. Because the triple property is a logical statement (a predicate), the data graph represents logical propositions or assertions accepted to be true about the subject matter. These logical formalizations can be manipulated to calculate new triples, representing inferred logical assertions, from the existing data.To demonstrate a MKB system, a technical proof-of-concept is developed that uses geographically attributed Resource Description Framework (RDF) serializations of linked data for mapping. The proof-of-concept focuses on accessing triple data from visual elements of a geographic map as the interface to the MKB. The map interface is embedded with other essential functions such as SPARQL Protocol and RDF Query Language (SPARQL) data query endpoint services and reasoning capabilities of Apache Marmotta (Apache Software Foundation, 2017). An RDF database of the Geographic Names Information System (GNIS), which contains official names of domestic feature in the United States, was linked to a county data layer from The National Map of the U.S. Geological Survey. The county data are part of a broader Government Units theme offered to the public as Esri shapefiles. The shapefile used to draw the map itself was converted to a geographic-oriented JavaScript Object Notation (JSON) (GeoJSON) format and linked through various properties with a linked geodata version of the GNIS database called “GNIS–LD” (Butler and others, 2016; B. Regalia and others, University of California-Santa Barbara, written commun., 2017). The GNIS–LD files originated in Terse RDF Triple Language (Turtle) format but were converted to a JSON format specialized in linked data, “JSON–LD” (Beckett and Berners-Lee, 2011; Sorny and others, 2014). The GNIS–LD database is composed of roughly three predominant triple data graphs: Features, Names, and History. The graphs include a set of namespace prefixes used by each of the attributes. Predefining the prefixes made the conversion to the JSON–LD format simple to complete because Turtle and JSON–LD are variant specifications of the basic RDF concept.To convert a shapefile into GeoJSON format to capture the geospatial coordinate geometry objects, an online converter, Mapshaper, was used (Bloch, 2013). To convert the Turtle files, a custom converter written in Java reconstructs the files by parsing each grouping of attributes belonging to one subject and pasting the data into a new file that follows the syntax of JSON–LD. Additionally, the Features file contained its own set of geometries, which was exported into a separate JSON–LD file along with its elevation value to form a fourth file, named “features-geo.json.” Extracted data from external files can be represented in HyperText Markup Language (HTML) path objects. The goal was to import multiple JSON–LD files using this approach.

A GeoNode-Based Multiscale Platform For Management, Visualization And Integration Of DInSAR Data With Different Geospatial Information Sources

NASA Astrophysics Data System (ADS)

Buonanno, Sabatino; Fusco, Adele; Zeni, Giovanni; Manunta, Michele; Lanari, Riccardo

2017-04-01

This work describes the implementation of an efficient system for managing, viewing, analyzing and updating remotely sensed data, with special reference to Differential Interferometric Synthetic Aperture Radar (DInSAR) data. The DInSAR products measure Earth surface deformation both in space and time, producing deformation maps and time series[1,2]. The use of these data in research or operational contexts requires tools that have to handle temporal and spatial variability with high efficiency. For this aim we present an implementation based on Spatial Data Infrastructure (SDI) for data integration, management and interchange, by using standard protocols[3]. SDI tools provide access to static datasets that operate only with spatial variability . In this paper we use the open source project GeoNode as framework to extend SDI infrastructure functionalities to ingest very efficiently DInSAR deformation maps and deformation time series. GeoNode allows to realize comprehensive and distributed infrastructure, following the standards of the Open Geospatial Consortium, Inc. - OGC, for remote sensing data management, analysis and integration [4,5]. In the current paper we explain the methodology used for manage the data complexity and data integration using the opens source project GeoNode. The solution presented in this work for the ingestion of DinSAR products is a very promising starting point for future developments of the OGC compliant implementation of a semi-automatic remote sensing data processing chain . [1] Berardino, P., Fornaro, G., Lanari, R., & Sansosti, E. (2002). A new Algorithm for Surface Deformation Monitoring based on Small Baseline Differential SAR Interferograms. IEEE Transactions on Geoscience and Remote Sensing, 40, 11, pp. 2375-2383. [2] Lanari R., F. Casu, M. Manzo, G. Zeni,, P. Berardino, M. Manunta and A. Pepe (2007), An overview of the Small Baseline Subset Algorithm: a DInSAR Technique for Surface Deformation Analysis, P. Appl. Geophys., 164, doi: 10.1007/s00024-007-0192-9. [3] Nebert, D.D. (ed). 2000. Developing Spatial data Infrastructures: The SDI Cookbook. [4] Geonode (www.geonode.org) [5] Kolodziej, k. (ed). 2004. OGC OpenGIS Web Map Server Cookbook. Open Geospatial Consortium, 1.0.2 edition.

Magnetic resonance imaging of folic acid-coated magnetite nanoparticles reflects tissue biodistribution of long-acting antiretroviral therapy.

PubMed

Li, Tianyuzi; Gendelman, Howard E; Zhang, Gang; Puligujja, Pavan; McMillan, JoEllyn M; Bronich, Tatiana K; Edagwa, Benson; Liu, Xin-Ming; Boska, Michael D

2015-01-01

Regimen adherence, systemic toxicities, and limited drug penetrance to viral reservoirs are obstacles limiting the effectiveness of antiretroviral therapy (ART). Our laboratory's development of the monocyte-macrophage-targeted long-acting nanoformulated ART (nanoART) carriage provides a novel opportunity to simplify drug-dosing regimens. Progress has nonetheless been slowed by cumbersome, but required, pharmacokinetic (PK), pharmacodynamics, and biodistribution testing. To this end, we developed a small magnetite ART (SMART) nanoparticle platform to assess antiretroviral drug tissue biodistribution and PK using magnetic resonance imaging (MRI) scans. Herein, we have taken this technique a significant step further by determining nanoART PK with folic acid (FA) decorated magnetite (ultrasmall superparamagnetic iron oxide [USPIO]) particles and by using SMART particles. FA nanoparticles enhanced the entry and particle retention to the reticuloendothelial system over nondecorated polymers after systemic administration into mice. These data were seen by MRI testing and validated by comparison with SMART particles and direct evaluation of tissue drug levels after nanoART. The development of alendronate (ALN)-coated magnetite thus serves as a rapid initial screen for the ability of targeting ligands to enhance nanoparticle-antiretroviral drug biodistribution, underscoring the value of decorated magnetite particles as a theranostic tool for improved drug delivery.

Magnetic resonance imaging of folic acid-coated magnetite nanoparticles reflects tissue biodistribution of long-acting antiretroviral therapy

PubMed Central

Li, Tianyuzi; Gendelman, Howard E; Zhang, Gang; Puligujja, Pavan; McMillan, JoEllyn M; Bronich, Tatiana K; Edagwa, Benson; Liu, Xin-Ming; Boska, Michael D

2015-01-01

Regimen adherence, systemic toxicities, and limited drug penetrance to viral reservoirs are obstacles limiting the effectiveness of antiretroviral therapy (ART). Our laboratory’s development of the monocyte-macrophage-targeted long-acting nanoformulated ART (nanoART) carriage provides a novel opportunity to simplify drug-dosing regimens. Progress has nonetheless been slowed by cumbersome, but required, pharmacokinetic (PK), pharmacodynamics, and biodistribution testing. To this end, we developed a small magnetite ART (SMART) nanoparticle platform to assess antiretroviral drug tissue biodistribution and PK using magnetic resonance imaging (MRI) scans. Herein, we have taken this technique a significant step further by determining nanoART PK with folic acid (FA) decorated magnetite (ultrasmall superparamagnetic iron oxide [USPIO]) particles and by using SMART particles. FA nanoparticles enhanced the entry and particle retention to the reticuloendothelial system over nondecorated polymers after systemic administration into mice. These data were seen by MRI testing and validated by comparison with SMART particles and direct evaluation of tissue drug levels after nanoART. The development of alendronate (ALN)-coated magnetite thus serves as a rapid initial screen for the ability of targeting ligands to enhance nanoparticle-antiretroviral drug biodistribution, underscoring the value of decorated magnetite particles as a theranostic tool for improved drug delivery. PMID:26082630

Biodistribution of Encapsulated Indocyanine Green in Healthy Mice

PubMed Central

Yaseen, Mohammad A.; Yu, Jie; Jung, Bongsu; Wong, Michael S.; Anvari, Bahman

2009-01-01

Indocyanine Green (ICG) is a fluorescent probe used in various optically-mediated diagnostic and therapeutic applications. However, utility of ICG remains limited by its unstable optical properties and non-specific localization. We have encapsulated ICG within electrostatically-assembled mesocapsules (MCs) to explore its potential for targeted optical diagnosis and therapy. In this study, we investigate how the surface coating and size of the MCs influences ICG's biodistribution in vivo. ICG was administered intravenously to Swiss Webster mice as a free solution or encapsulated within either 100 nm diameter MCs coated with dextran; 500 nm diameter MCs coated with dextran; or 100 nm diameter MCs coated with 10 nm ferromagnetic iron oxide nanoparticles, themselves coated with polyethylene glycol. ICG was extracted from harvested blood and organs at various times and its amount quantified with fluorescence measurements. MCs containing ICG accumulated in organs of the reticuloendothelial system, namely the liver and spleen, as well as the lungs. The circulation kinetics of ICG remained unaffected by encapsulation; however, the deposition within organs other than the liver suggests a different biodistribution mechanism. Results suggest that the capsules' coating influences their biodistribution to a greater extent than their size. The MC encapsulation system allows for delivery of ICG to organs other than the liver, enabling the potential development of new optical imaging and therapeutic strategies. PMID:19799463

Noise tolerant spatiotemporal chaos computing.

PubMed

Kia, Behnam; Kia, Sarvenaz; Lindner, John F; Sinha, Sudeshna; Ditto, William L

2014-12-01

We introduce and design a noise tolerant chaos computing system based on a coupled map lattice (CML) and the noise reduction capabilities inherent in coupled dynamical systems. The resulting spatiotemporal chaos computing system is more robust to noise than a single map chaos computing system. In this CML based approach to computing, under the coupled dynamics, the local noise from different nodes of the lattice diffuses across the lattice, and it attenuates each other's effects, resulting in a system with less noise content and a more robust chaos computing architecture.

Accuracy and Significance of Polymerase Chain Reaction Detection of Sentinel Node Metastases in Breast Cancer Patients

DTIC Science & Technology

2000-10-01

oral presentation at the 1 998 AACR meeting and on the subsequent Cancer Research article, many investigators in the field have abandoned K19 as a...1999) "Comparison of Intradermal and Subcutaneous Injections in Lymphatic Mapping." Oral presentation_at the 33rd Annual Meeting of the Association of...Lannin D, Tafra L. Comparison of Intradermal and Subcutaneous Injections in Lymphatic Mapping, Oral presentation at the 33rd Annual Meeting of the

Noise tolerant spatiotemporal chaos computing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kia, Behnam; Kia, Sarvenaz; Ditto, William L.

We introduce and design a noise tolerant chaos computing system based on a coupled map lattice (CML) and the noise reduction capabilities inherent in coupled dynamical systems. The resulting spatiotemporal chaos computing system is more robust to noise than a single map chaos computing system. In this CML based approach to computing, under the coupled dynamics, the local noise from different nodes of the lattice diffuses across the lattice, and it attenuates each other's effects, resulting in a system with less noise content and a more robust chaos computing architecture.

A simplified interventional mapping system (SIMS) for the selection of combinations of targeted treatments in non-small cell lung cancer

PubMed Central

Lazar, Vladimir; Martini, Jean-François; Gomez-Navarro, Jesus; Yver, Antoine; Kan, Zhengyin; Dry, Jonathan R.; Kehren, Jeanne; Validire, Pierre; Rodon, Jordi; Vielh, Philippe; Ducreux, Michel; Galbraith, Susan; Lehnert, Manfred; Onn, Amir; Berger, Raanan; Pierotti, Marco A.; Porgador, Angel; Pramesh, CS; Ye, Ding-wei; Carvalho, Andre L.; Batist, Gerald; Le Chevalier, Thierry; Morice, Philippe; Besse, Benjamin; Vassal, Gilles; Mortlock, Andrew; Hansson, Johan; Berindan-Neagoe, Ioana; Dann, Robert; Haspel, Joel; Irimie, Alexandru; Laderman, Steve; Nechushtan, Hovav; Al Omari, Amal S.; Haywood, Trent; Bresson, Catherine; Soo, Khee Chee; Osman, Iman; Mata, Hilario; Lee, Jack J.; Jhaveri, Komal; Meurice, Guillaume; Palmer, Gary; Lacroix, Ludovic; Koscielny, Serge; Eterovic, Karina Agda; Blay, Jean-Yves; Buller, Richard; Eggermont, Alexander; Schilsky, Richard L.; Mendelsohn, John; Soria, Jean-Charles; Rothenberg, Mace

2015-01-01

Non-small cell lung cancer (NSCLC) is a leading cause of death worldwide. Targeted monotherapies produce high regression rates, albeit for limited patient subgroups, who inevitably succumb. We present a novel strategy for identifying customized combinations of triplets of targeted agents, utilizing a simplified interventional mapping system (SIMS) that merges knowledge about existent drugs and their impact on the hallmarks of cancer. Based on interrogation of matched lung tumor and normal tissue using targeted genomic sequencing, copy number variation, transcriptomics, and miRNA expression, the activation status of 24 interventional nodes was elucidated. An algorithm was developed to create a scoring system that enables ranking of the activated interventional nodes for each patient. Based on the trends of co-activation at interventional points, combinations of drug triplets were defined in order to overcome resistance. This methodology will inform a prospective trial to be conducted by the WIN consortium, aiming to significantly impact survival in metastatic NSCLC and other malignancies. PMID:25944621

Maximally informative pairwise interactions in networks

PubMed Central

Fitzgerald, Jeffrey D.; Sharpee, Tatyana O.

2010-01-01

Several types of biological networks have recently been shown to be accurately described by a maximum entropy model with pairwise interactions, also known as the Ising model. Here we present an approach for finding the optimal mappings between input signals and network states that allow the network to convey the maximal information about input signals drawn from a given distribution. This mapping also produces a set of linear equations for calculating the optimal Ising-model coupling constants, as well as geometric properties that indicate the applicability of the pairwise Ising model. We show that the optimal pairwise interactions are on average zero for Gaussian and uniformly distributed inputs, whereas they are nonzero for inputs approximating those in natural environments. These nonzero network interactions are predicted to increase in strength as the noise in the response functions of each network node increases. This approach also suggests ways for how interactions with unmeasured parts of the network can be inferred from the parameters of response functions for the measured network nodes. PMID:19905153

Quantum dot nanoparticle for optimization of breast cancer diagnostics and therapy in a clinical setting.

PubMed

Radenkovic, Dina; Kobayashi, Hisataka; Remsey-Semmelweis, Ernö; Seifalian, Alexander M

2016-08-01

Breast cancer is the most common cancer in the world. Sentinel lymph node (SLN) biopsy is used for staging of axillary lymph nodes. Organic dyes and radiocolloid are currently used for SLN mapping, but expose patients to ionizing radiation, are unstable during surgery and cause local tissue damage. Quantum dots (QD) could be used for SLN mapping without the need for biopsy. Surgical resection of the primary tumor is the optimal treatment for early-diagnosed breast cancer, but due to difficulties in defining tumor margins, cancer cells often remain leading to reoccurrences. Functionalized QD could be used for image-guided tumor resection to allow visualization of cancer cells. Near Infrared QD are photostable and have improved deep tissue penetration. Slow elimination of QD raises concerns of potential accumulation. Nevertheless, promising findings with cadmium-free QD in recent in vivo studies and first in-human trial suggest huge potential for cancer diagnostic and therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

Replacing colour blindness with Depth Perception

NASA Astrophysics Data System (ADS)

Matthews, Jaymie M.

Until recently, most work on rapidly oscillating Ap (roAp) stars has concentrated on rapid single-bandpass photometry, which efficiently samples their short periods even with telescopes of modest aperture. Global campaigns of this nature have yielded eigenfrequency spectra essential to asteroseismology. However, we have reached a threshold where such data must be supplemented with rapid spectroscopy and photometry at many bandpasses if we are to (a) identify the modes in roAp stars, and (b) fully exploit those modes to probe the stars' atmospheres and interiors. Studies by Medupe & Kurtz and Matthews raise the prospect of using the wavelength dependence of oscillation amplitude to map pulsational dynamics and/or atmospheric structure in roAp stars. Also, precise measurements of velocity oscillations through rapid high-resolution spectroscopy suggest that spectral lines from different ions behave differently. Given the chemical stratification and inhomogeneities of peculiar atmospheres, this may be a way to map spherical harmonic modes in 3-D (i.e., depths of upper radial nodes and positions of the surface nodes).

Mycobacterium avium subsp. paratuberculosis in dairy products, meat, and drinking water.

PubMed

Gill, C O; Saucier, L; Meadus, W J

2011-03-01

Mycobacterium avium subsp. paratuberculosis (Map) is the cause of Johne's disease, a chronic infection of the gut, in ruminant animals that provide milk and/or meat for human consumption. Map also may be involved in Crohn's disease and type 1 diabetes in humans. Although the role of Map in human diseases has not been established, minimizing the exposure of humans to the organism is considered desirable as a precautionary measure. Infected animals can shed Map in feces and milk, and the organism can become disseminated in tissues remote from the gut and its associated lymph nodes. The presence of at least some Map in raw milk and meat and in natural waters is likely, but the numbers of Map in those foods and waters should be reduced through cooking or purification. The available information relating to Map in milk and dairy products, meats, and drinking water is reviewed here for assessment of the risks of exposure to Map from consumption of such foods and water.

Gene expression profiling reveals a massive, aneuploidy-dependent transcriptional deregulation and distinct differences between lymph node-negative and lymph node-positive colon carcinomas.

PubMed

Grade, Marian; Hörmann, Patrick; Becker, Sandra; Hummon, Amanda B; Wangsa, Danny; Varma, Sudhir; Simon, Richard; Liersch, Torsten; Becker, Heinz; Difilippantonio, Michael J; Ghadimi, B Michael; Ried, Thomas

2007-01-01

To characterize patterns of global transcriptional deregulation in primary colon carcinomas, we did gene expression profiling of 73 tumors [Unio Internationale Contra Cancrum stage II (n = 33) and stage III (n = 40)] using oligonucleotide microarrays. For 30 of the tumors, expression profiles were compared with those from matched normal mucosa samples. We identified a set of 1,950 genes with highly significant deregulation between tumors and mucosa samples (P < 1e-7). A significant proportion of these genes mapped to chromosome 20 (P = 0.01). Seventeen genes had a >5-fold average expression difference between normal colon mucosa and carcinomas, including up-regulation of MYC and of HMGA1, a putative oncogene. Furthermore, we identified 68 genes that were significantly differentially expressed between lymph node-negative and lymph node-positive tumors (P < 0.001), the functional annotation of which revealed a preponderance of genes that play a role in cellular immune response and surveillance. The microarray-derived gene expression levels of 20 deregulated genes were validated using quantitative real-time reverse transcription-PCR in >40 tumor and normal mucosa samples with good concordance between the techniques. Finally, we established a relationship between specific genomic imbalances, which were mapped for 32 of the analyzed colon tumors by comparative genomic hybridization, and alterations of global transcriptional activity. Previously, we had conducted a similar analysis of primary rectal carcinomas. The systematic comparison of colon and rectal carcinomas revealed a significant overlap of genomic imbalances and transcriptional deregulation, including activation of the Wnt/beta-catenin signaling cascade, suggesting similar pathogenic pathways.

Tissue accumulation and urinary excretion of Cr in chromium picolinate (CrPic)-supplemented lambs.

PubMed

Dallago, Bruno Stéfano Lima; Lima, Bárbara Alcântara Ferreira; Braz, Shélida Vasconcelos; Mustafa, Vanessa da Silva; McManus, Concepta; Paim, Tiago do Prado; Campeche, Aline; Gomes, Edgard Franco; Louvandini, Helder

2016-05-01

Chromium (Cr) concentrations in liver, kidney, spleen, heart, lymph node, skeletal muscle, bone, testis and urine of lambs were measured to trace the biodistribution and bioaccumulation of Cr after oral supplementation with chromium picolinate (CrPic). Twenty-four Santa Inês lambs were treated with four different concentrations of CrPic: placebo, 0.250, 0.375 and 0.500 mg of CrPic/animal/day for 84 days. The basal diet consisted of Panicum maximum cv Massai hay and concentrate. Cr concentrations were measured by ICP-MS measuring (52)Cr as collected mass. There was a positive linear relationship between dose administered and the accumulation of Cr in the heart, lungs and testis. Urinary excretion of Cr occurred in a time and dose-dependent manner, so the longer or more dietary Cr provided, the greater excretion of the element. As some non-carcass components (such as lungs or heart) are added to bone and visceral meal to feed animals, there is a risk of bioaccumulation and biomagnification due to Cr offered as CrPic in the diet. Copyright © 2016 Elsevier GmbH. All rights reserved.

(99m)Tc-EDDA/HYNIC-octreotate - a new radiotracer for detection and staging of NET: a case of metastatic duodenal carcinoid.

PubMed

Hubalewska-Dydejczyk, Alicja; Szybiński, Piotr; Fröss-Baron, Katarzyna; Mikolajczak, Renata; Huszno, Bohdan; Sowa-Staszczak, Anna

2005-01-01

Somatostatin receptor scintigraphy (SRS) has become a routine imaging method for the diagnostics of neuroendocrine tumours (NET). (99m)Tc-EDDA/HYNIC-octreotate (Polatom, Poland) is a new radiotracer with high affinity for SSTR2 and similar physiological biodistribution to (111)In-Octreoscan. We present a case of a 47-year-old man with disseminated duodenal carcinoid. The patient had been operated due to the tumour mass detected in pancreatic head area. Histopathology revealed carcinoid of the duodenal wall with local lymph node and liver metastases. The patient was qualified for chemotherapy stopped due to severe leucopenia. (99m)Tc EDDA/HYNIC-octreotate scintigraphy was performed for staging and to determine SSTR status of the tumour before planned 90Y-DOTATATE therapy. The multiple metastatic lesions were detected all over the body. The high quality images with high target/non target ratio were obtained. (99m)Tc-MDP scintigraphy confirmed multiple bone metastases. On the basis of SRS result the patient was qualified for 90Y-DOTA-TATE therapy. In conclusion, (99m)Tc EDDA/HYNIC-octreotate can be regarded as a promising tracer for staging and to determine SSTR status of NET.

Partnership For Edge Physics Simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parashar, Manish

In this effort, we will extend our prior work as part of CPES (i.e., DART and DataSpaces) to support in-situ tight coupling between application codes that exploits data locality and core-level parallelism to maximize on-chip data exchange and reuse. This will be accomplished by mapping coupled simulations so that the data exchanges are more localized within the nodes. Coupled simulation workflows can more effectively utilize the resources available on emerging HEC platforms if they can be mapped and executed to exploit data locality as well as the communication patterns between application components. Scheduling and running such workflows requires an extendedmore » framework that should provide a unified hybrid abstraction to enable coordination and data sharing across computation tasks that run on the heterogeneous multi-core-based systems, and develop a data-locality based dynamic tasks scheduling approach to increase on-chip or intra-node data exchanges and in-situ execution. This effort will extend our prior work as part of CPES (i.e., DART and DataSpaces), which provided a simple virtual shared-space abstraction hosted at the staging nodes, to support application coordination, data sharing and active data processing services. Moreover, it will transparently manage the low-level operations associated with the inter-application data exchange, such as data redistributions, and will enable running coupled simulation workflow on multi-cores computing platforms.« less

Investigation on iterative multiuser detection physical layer network coding in two-way relay free-space optical links with turbulences and pointing errors.

PubMed

Abu-Almaalie, Zina; Ghassemlooy, Zabih; Bhatnagar, Manav R; Le-Minh, Hoa; Aslam, Nauman; Liaw, Shien-Kuei; Lee, It Ee

2016-11-20

Physical layer network coding (PNC) improves the throughput in wireless networks by enabling two nodes to exchange information using a minimum number of time slots. The PNC technique is proposed for two-way relay channel free space optical (TWR-FSO) communications with the aim of maximizing the utilization of network resources. The multipair TWR-FSO is considered in this paper, where a single antenna on each pair seeks to communicate via a common receiver aperture at the relay. Therefore, chip interleaving is adopted as a technique to separate the different transmitted signals at the relay node to perform PNC mapping. Accordingly, this scheme relies on the iterative multiuser technique for detection of users at the receiver. The bit error rate (BER) performance of the proposed system is examined under the combined influences of atmospheric loss, turbulence-induced channel fading, and pointing errors (PEs). By adopting the joint PNC mapping with interleaving and multiuser detection techniques, the BER results show that the proposed scheme can achieve a significant performance improvement against the degrading effects of turbulences and PEs. It is also demonstrated that a larger number of simultaneous users can be supported with this new scheme in establishing a communication link between multiple pairs of nodes in two time slots, thereby improving the channel capacity.

Effect of obesity on biodistribution of nanoparticles.

PubMed

de Jesus Felismino, Claudiana; Helal-Neto, Edward; Portilho, Filipe Leal; Rocha Pinto, Suyene; Sancenón, Félix; Martínez-Máñez, Ramón; de Assis Ferreira, Agatha; da Silva, Simone Vargas; Barja-Fidalgo, Thereza Christina; Santos-Oliveira, Ralph

2018-05-10

Nanoparticles have specific features (lipophilicity, surface charge, composition and size). Studies regarding the biological behavior of nanoparticles in diseases such diabetics and obesity are scarce. Here, we evaluated two nanoparticles: magnetic core mesoporous silica (MSN) (58 nm) and polycaprolactone (PCL) nanoparticle (280 nm) in obese mice. Changes in the biodistribution were observed, especially considering the mononuclear phagocyte system (MPS), and the visceral fat tissue. Nonetheless, our data corroborates the influence of size in the biodistribution in obese animals, supporting that smaller nanoparticles, may show a higher tissue deposition at spleen, due the associated splenomegaly and the complications arising from this state. Finally, our study demonstrated that, in obesity, probably due the low-grade inflammatory state associated with metabolic syndrome a difference in accumulation of nanoparticles wasfound, with profound impact in the tissue deposition of nanoparticles. Copyright © 2018 Elsevier B.V. All rights reserved.

Novel methodology for labelling mesoporous silica nanoparticles using the 18F isotope and their in vivo biodistribution by positron emission tomography

NASA Astrophysics Data System (ADS)

Rojas, Santiago; Gispert, Juan Domingo; Menchón, Cristina; Baldoví, Herme G.; Buaki-Sogo, Mireia; Rocha, Milagros; Abad, Sergio; Victor, Victor Manuel; García, Hermenegildo; Herance, José Raúl

2015-03-01

Nanoparticles have been proposed for several biomedical applications due to their potential as drug carriers, diagnostic and therapeutic agents. However, only a few of them have been approved for their use in humans. In order to gauge the potential applicability of a specific type of nanoparticle, in vivo biodistribution studies to characterize their pharmacokinetic properties are essential. In this regard, mesoporous silica nanoparticles (30-130 nm) have been functionalized with amino groups in order to react with N-succinimidyl 4-[18F]fluorobenzoate and thus anchor the 18F positron emission isotope by using a novel and easy labelling strategy. In vivo biodistribution was characterized in mice after intravenous administration of radiolabelled nanoparticles by positron emission tomography. Our results indicated that radiolabelled mesoporous silica nanoparticles were excreted into bile and urine and accumulated mainly in the organs of the reticuloendothelial system and lungs.

Biocompatibility and biodistribution of functionalized carbon nano-onions (f-CNOs) in a vertebrate model

NASA Astrophysics Data System (ADS)

D' Amora, Marta; Rodio, Marina; Bartelmess, Juergen; Sancataldo, Giuseppe; Brescia, Rosaria; Cella Zanacchi, Francesca; Diaspro, Alberto; Giordani, Silvia

2016-09-01

Functionalized carbon nano-onions (f-CNOs) are of great interest as platforms for imaging, diagnostic and therapeutic applications due to their high cellular uptake and low cytotoxicity. To date, the toxicological effects of f-CNOs on vertebrates have not been reported. In this study, the possible biological impact of f-CNOs on zebrafish during development is investigated, evaluating different toxicity end-points such as the survival rate, hatching rate, and heart beat rate. Furthermore, a bio-distribution study of boron dipyrromethene (BODIPY) functionalized CNOs in zebrafish larvae is performed by utilizing inverted selective plane illumination microscopy (iSPIM), due to its intrinsic capability of allowing for fast 3D imaging. Our in vivo findings indicate that f-CNOs exhibit no toxicity, good biocompatibility (in the concentration range of 5-100 μg mL-1) and a homogenous biodistribution in zebrafish larvae.

Physiologically based pharmacokinetic modeling of polyethylene glycol-coated polyacrylamide nanoparticles in rats.

PubMed

Li, Dingsheng; Johanson, Gunnar; Emond, Claude; Carlander, Ulrika; Philbert, Martin; Jolliet, Olivier

2014-08-01

Nanoparticles' health risks depend on their biodistribution in the body. Phagocytosis may greatly affect this distribution but has not yet explicitly accounted for in whole body pharmacokinetic models. Here, we present a physiologically based pharmacokinetic model that includes phagocytosis of nanoparticles to explore the biodistribution of intravenously injected polyethylene glycol-coated polyacrylamide nanoparticles in rats. The model explains 97% of the observed variation in nanoparticles amounts across organs. According to the model, phagocytizing cells quickly capture nanoparticles until their saturation and thereby constitute a major reservoir in richly perfused organs (spleen, liver, bone marrow, lungs, heart and kidneys), storing 83% of the nanoparticles found in these organs 120 h after injection. Key determinants of the nanoparticles biodistribution are the uptake capacities of phagocytizing cells in organs, the partitioning between tissue and blood, and the permeability between capillary blood and tissues. This framework can be extended to other types of nanoparticles by adapting these determinants.

Altered [99mTc]Tc-MDP biodistribution from neutron activation sourced 99Mo.

PubMed

Demeter, Sandor; Szweda, Roman; Patterson, Judy; Grigoryan, Marine

2018-01-01

Given potential worldwide shortages of fission sourced 99 Mo/ 99m Tc medical isotopes there is increasing interest in alternate production strategies. A neutron activated 99 Mo source was utilized in a single center phase III open label study comparing 99m Tc, as 99m Tc Methylene Diphosphonate ([ 99m Tc]Tc-MDP), obtained from solvent generator separation of neutron activation produced 99 Mo, versus nuclear reactor produced 99 Mo (e.g., fission sourced) in oncology patients for which an [ 99m Tc]Tc-MDP bone scan would normally have been indicated. Despite the investigational [ 99m Tc]Tc-MDP passing all standard, and above standard of care, quality assurance tests, which would normally be sufficient to allow human administration, there was altered biodistribution which could lead to erroneous clinical interpretation. The cause of the altered biodistribution remains unknown and requires further research.

Fluorescent Labeling and Biodistribution of Latex Nanoparticles Formed by Surfactant-Free RAFT Emulsion Polymerization.

PubMed

Poon, Cheuk Ka; Tang, Owen; Chen, Xin-Ming; Kim, Byung; Hartlieb, Matthias; Pollock, Carol A; Hawkett, Brian S; Perrier, Sébastien

2017-10-01

The authors report the preparation of a novel range of functional polyacrylamide stabilized polystyrene nanoparticles, obtained by surfactant-free reversible addition-fragmentation chain transfer (RAFT) emulsion polymerization, their fluorescent tagging, cellular uptake, and biodistribution. The authors show the versatility of the RAFT emulsion process for the design of functional nanoparticles of well-defined size that can be used as drug delivery vectors. Functionalization with a fluorescent tag offers a useful visualization tool for tracing, localization, and clearance studies of these carriers in biological models. The studies are carried out by labeling the sterically stabilized latex particles chemically with rhodamine B. The fluorescent particles are incubated in a healthy human renal proximal tubular cell line model, and intravenously injected into a mouse model. Cellular localization and biodistribution of these particles on the biological models are explored. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Simplifying Logistics and Avoiding the Unnecessary in Patients With Breast Cancer Undergoing Sentinel Node Biopsy. A Prospective Feasibility Trial of the Preoperative Injection of Super Paramagnetic Iron Oxide Nanoparticles.

PubMed

Karakatsanis, A; Olofsson, H; Stålberg, P; Bergkvist, L; Abdsaleh, S; Wärnberg, F

2018-06-01

Sentinel node is routinely localized with the intraoperative use of a radioactive tracer, involving challenging logistics. Super paramagnetic iron oxide nanoparticle is a non-radioactive tracer with comparable performance that could allow for preoperative localization, would simplify the procedure, and possibly be of value in axillary mapping before neoadjuvant treatment. The current trial aimed to determine the a priori hypothesis that the injection of super paramagnetic iron oxide nanoparticles in the preoperative period for the localization of the sentinel node is feasible. This is a prospective feasibility trial, conducted from 9 September 2014 to 22 October 2014 at Uppsala University Hospital. In all, 12 consecutive patients with primary breast cancer planned for resection of the primary and sentinel node biopsy were recruited. Super paramagnetic iron oxide nanoparticles were injected in the preoperative visit in the outpatient clinic. The radioactive tracer ( 99 mTc) and the blue dye were injected perioperatively in standard fashion. A volunteer was injected with super paramagnetic iron oxide nanoparticles to follow the decline in the magnetic signal in the sentinel node over time. The primary outcome was successful sentinel node detection. Super paramagnetic iron oxide nanoparticles' detection after preoperative injection (3-15 days) was successful in all cases (100%). In the volunteer, axillary signal was presented for 4 weeks. No adverse effects were noted. Conclusion and relevance: Preoperative super paramagnetic iron oxide nanoparticles' injection is feasible and leads to successful detection of the sentinel node. That may lead to simplified logistics as well as the identification, sampling, and marking of the sentinel node in patients planned for neoadjuvant treatment.

Shock waves on complex networks

NASA Astrophysics Data System (ADS)

Mones, Enys; Araújo, Nuno A. M.; Vicsek, Tamás; Herrmann, Hans J.

2014-05-01

Power grids, road maps, and river streams are examples of infrastructural networks which are highly vulnerable to external perturbations. An abrupt local change of load (voltage, traffic density, or water level) might propagate in a cascading way and affect a significant fraction of the network. Almost discontinuous perturbations can be modeled by shock waves which can eventually interfere constructively and endanger the normal functionality of the infrastructure. We study their dynamics by solving the Burgers equation under random perturbations on several real and artificial directed graphs. Even for graphs with a narrow distribution of node properties (e.g., degree or betweenness), a steady state is reached exhibiting a heterogeneous load distribution, having a difference of one order of magnitude between the highest and average loads. Unexpectedly we find for the European power grid and for finite Watts-Strogatz networks a broad pronounced bimodal distribution for the loads. To identify the most vulnerable nodes, we introduce the concept of node-basin size, a purely topological property which we show to be strongly correlated to the average load of a node.

Decision-Making Strategies for College Students

ERIC Educational Resources Information Center

Morey, Janis T.; Dansereau, Donald F.

2010-01-01

College students' decision making is often less than optimal and sometimes leads to negative consequences. The effectiveness of two strategies for improving student decision making--node-link mapping and social perspective taking (SPT)--are examined. Participants using SPT were significantly better able to evaluate decision options and develop…

Renormalization group theory for percolation in time-varying networks.

PubMed

Karschau, Jens; Zimmerling, Marco; Friedrich, Benjamin M

2018-05-22

Motivated by multi-hop communication in unreliable wireless networks, we present a percolation theory for time-varying networks. We develop a renormalization group theory for a prototypical network on a regular grid, where individual links switch stochastically between active and inactive states. The question whether a given source node can communicate with a destination node along paths of active links is equivalent to a percolation problem. Our theory maps the temporal existence of multi-hop paths on an effective two-state Markov process. We show analytically how this Markov process converges towards a memoryless Bernoulli process as the hop distance between source and destination node increases. Our work extends classical percolation theory to the dynamic case and elucidates temporal correlations of message losses. Quantification of temporal correlations has implications for the design of wireless communication and control protocols, e.g. in cyber-physical systems such as self-organized swarms of drones or smart traffic networks.

Near infrared fluorescent chlorophyll nanoscale liposomes for sentinel lymph node mapping

PubMed Central

Fan, Lina; Wu, Qiang; Chu, Maoquan

2012-01-01

Background Sentinel lymph node (SLN) mapping using in vivo near infrared fluorescence imaging has attracted great attention during the past few years. Here we report on the early use of poorly water-soluble chlorophyll with near infrared fluorescence extracted from the leaf of Chimonanthus salicifolius, for mouse axillary SLN mapping. Methods and results To improve the water solubility and SLN targeting of the chlorophyll, we encapsulated the chlorophyll in nanoscale liposomes. The liposome-coated chlorophyll nanocomposites obtained were spherical in shape and had an average diameter of 21.7 ± 6.0 nm. The nanocomposites dispersed well in water, and in aqueous suspension they exhibited brighter near infrared fluorescence than chlorophyll alone. After incubation of the nanocomposites with normal liver cells (QSG-7701) and macrophage cells (Ana-1) for no more than 48 hours, there was no obvious reduction in cell viability. When the nanocomposites were injected intradermally into the paw of a mouse, the axillary SLN was found to be strongly fluorescent and was easily visualized in real time without a requirement for surgery. The intensity of the near infrared fluorescence emitted by the SLN was obviously brighter than that emitted by the SLN of another mouse that had been intradermally injected with chlorophyll alone. Conclusion Our data show that the liposome-coated chlorophyll nanocomposites could have great potential for clinical SLN mapping due to their lack of toxicity, bright near infrared fluorescence, and small diameter. PMID:22787402

Near-infrared Fluorescence-guided Sentinel Node Mapping of the Ovary With Indocyanine Green in a Minimally Invasive Setting: A Feasible Study.

PubMed

Buda, Alessandro; Passoni, Paolo; Corrado, Giacomo; Bussi, Beatrice; Cutillo, Giuseppe; Magni, Sonia; Vizza, Enrico

2017-01-01

Sentinel lymph node (SLN) mapping has increased its feasibility in both early-stage cervical and endometrial cancer. There are few SLN studies regarding the ovary because of the risk of tumor dissemination and perhaps because the ovary represents an inconvenient site for injection. In this preliminary study, we have shown the feasibility of SLN mapping of the ovary with indocyanine green during laparoscopic retroperitoneal aortic surgical staging. The 10 women who were included in this study underwent aortic with pelvic laparoscopic staging, which included SLN biopsy, extrafascial total hysterectomy, and bilateral salpingo-oophorectomy in case of an ovarian tumor. The fluorescent dye was injected on the dorsal and ventral side of the proper ovarian ligament and the suspensory ligament, close to the ovary and just underneath the peritoneum. In all cases except 1, SLNs were detected soon after the injection in the aortic compartment and in 3 cases also in the common iliac region. Only 1 intraoperative complication occurred: a superficial lesion of the vena cava that was recovered with a laparoscopic suture. Laparoscopic ovarian SLN mapping performed by means of an injection of indocyanine green fluorescent tracer in the ovarian ligaments seems feasible and promising. Further investigation are encouraged and necessary to evaluate the possible applications of this new technique for staging patients with early-stage ovarian cancer. Copyright © 2016 AAGL. Published by Elsevier Inc. All rights reserved.

MaPLE: A MapReduce Pipeline for Lattice-based Evaluation and Its Application to SNOMED CT

PubMed Central

Zhang, Guo-Qiang; Zhu, Wei; Sun, Mengmeng; Tao, Shiqiang; Bodenreider, Olivier; Cui, Licong

2015-01-01

Non-lattice fragments are often indicative of structural anomalies in ontological systems and, as such, represent possible areas of focus for subsequent quality assurance work. However, extracting the non-lattice fragments in large ontological systems is computationally expensive if not prohibitive, using a traditional sequential approach. In this paper we present a general MapReduce pipeline, called MaPLE (MapReduce Pipeline for Lattice-based Evaluation), for extracting non-lattice fragments in large partially ordered sets and demonstrate its applicability in ontology quality assurance. Using MaPLE in a 30-node Hadoop local cloud, we systematically extracted non-lattice fragments in 8 SNOMED CT versions from 2009 to 2014 (each containing over 300k concepts), with an average total computing time of less than 3 hours per version. With dramatically reduced time, MaPLE makes it feasible not only to perform exhaustive structural analysis of large ontological hierarchies, but also to systematically track structural changes between versions. Our change analysis showed that the average change rates on the non-lattice pairs are up to 38.6 times higher than the change rates of the background structure (concept nodes). This demonstrates that fragments around non-lattice pairs exhibit significantly higher rates of change in the process of ontological evolution. PMID:25705725

Multi-Disciplinary, Multi-Fidelity Discrete Data Transfer Using Degenerate Geometry Forms

NASA Technical Reports Server (NTRS)

Olson, Erik D.

2016-01-01

In a typical multi-fidelity design process, different levels of geometric abstraction are used for different analysis methods, and transitioning from one phase of design to the next often requires a complete re-creation of the geometry. To maintain consistency between lower-order and higher-order analysis results, Vehicle Sketch Pad (OpenVSP) recently introduced the ability to generate and export several degenerate forms of the geometry, representing the type of abstraction required to perform low- to medium-order analysis for a range of aeronautical disciplines. In this research, the functionality of these degenerate models was extended, so that in addition to serving as repositories for the geometric information that is required as input to an analysis, the degenerate models can also store the results of that analysis mapped back onto the geometric nodes. At the same time, the results are also mapped indirectly onto the nodes of lower-order degenerate models using a process called aggregation, and onto higher-order models using a process called disaggregation. The mapped analysis results are available for use by any subsequent analysis in an integrated design and analysis process. A simple multi-fidelity analysis process for a single-aisle subsonic transport aircraft is used as an example case to demonstrate the value of the approach.

Virtual Network Embedding via Monte Carlo Tree Search.

PubMed

Haeri, Soroush; Trajkovic, Ljiljana

2018-02-01

Network virtualization helps overcome shortcomings of the current Internet architecture. The virtualized network architecture enables coexistence of multiple virtual networks (VNs) on an existing physical infrastructure. VN embedding (VNE) problem, which deals with the embedding of VN components onto a physical network, is known to be -hard. In this paper, we propose two VNE algorithms: MaVEn-M and MaVEn-S. MaVEn-M employs the multicommodity flow algorithm for virtual link mapping while MaVEn-S uses the shortest-path algorithm. They formalize the virtual node mapping problem by using the Markov decision process (MDP) framework and devise action policies (node mappings) for the proposed MDP using the Monte Carlo tree search algorithm. Service providers may adjust the execution time of the MaVEn algorithms based on the traffic load of VN requests. The objective of the algorithms is to maximize the profit of infrastructure providers. We develop a discrete event VNE simulator to implement and evaluate performance of MaVEn-M, MaVEn-S, and several recently proposed VNE algorithms. We introduce profitability as a new performance metric that captures both acceptance and revenue to cost ratios. Simulation results show that the proposed algorithms find more profitable solutions than the existing algorithms. Given additional computation time, they further improve embedding solutions.

MaPLE: A MapReduce Pipeline for Lattice-based Evaluation and Its Application to SNOMED CT.

PubMed

Zhang, Guo-Qiang; Zhu, Wei; Sun, Mengmeng; Tao, Shiqiang; Bodenreider, Olivier; Cui, Licong

2014-10-01

Non-lattice fragments are often indicative of structural anomalies in ontological systems and, as such, represent possible areas of focus for subsequent quality assurance work. However, extracting the non-lattice fragments in large ontological systems is computationally expensive if not prohibitive, using a traditional sequential approach. In this paper we present a general MapReduce pipeline, called MaPLE (MapReduce Pipeline for Lattice-based Evaluation), for extracting non-lattice fragments in large partially ordered sets and demonstrate its applicability in ontology quality assurance. Using MaPLE in a 30-node Hadoop local cloud, we systematically extracted non-lattice fragments in 8 SNOMED CT versions from 2009 to 2014 (each containing over 300k concepts), with an average total computing time of less than 3 hours per version. With dramatically reduced time, MaPLE makes it feasible not only to perform exhaustive structural analysis of large ontological hierarchies, but also to systematically track structural changes between versions. Our change analysis showed that the average change rates on the non-lattice pairs are up to 38.6 times higher than the change rates of the background structure (concept nodes). This demonstrates that fragments around non-lattice pairs exhibit significantly higher rates of change in the process of ontological evolution.

Sentinel Lymph Node Detection Using Carbon Nanoparticles in Patients with Early Breast Cancer

PubMed Central

Lu, Jianping; Zeng, Yi; Chen, Xia; Yan, Jun

2015-01-01

Purpose Carbon nanoparticles have a strong affinity for the lymphatic system. The purpose of this study was to evaluate the feasibility of sentinel lymph node biopsy using carbon nanoparticles in early breast cancer and to optimize the application procedure. Methods Firstly, we performed a pilot study to demonstrate the optimized condition using carbon nanoparticles for sentinel lymph nodes (SLNs) detection by investigating 36 clinically node negative breast cancer patients. In subsequent prospective study, 83 patients with clinically node negative breast cancer were included to evaluate SLNs using carbon nanoparticles. Another 83 SLNs were detected by using blue dye. SLNs detection parameters were compared between the methods. All patients irrespective of the SLNs status underwent axillary lymph node dissection for verification of axillary node status after the SLN biopsy. Results In pilot study, a 1 ml carbon nanoparticles suspension used 10–15min before surgery was associated with the best detection rate. In subsequent prospective study, with carbon nanoparticles, the identification rate, accuracy, false negative rate was 100%, 96.4%, 11.1%, respectively. The identification rate and accuracy were 88% and 95.5% with 15.8% of false negative rate using blue dye technique. The use of carbon nanoparticles suspension showed significantly superior results in identification rate (p = 0.001) and reduced false-negative results compared with blue dye technique. Conclusion Our study demonstrated feasibility and accuracy of using carbon nanoparticles for SLNs mapping in breast cancer patients. Carbon nanoparticles are useful in SLNs detection in institutions without access to radioisotope. PMID:26296136

Role of the node in controlling traffic of cadmium, zinc, and manganese in rice

PubMed Central

Yamaguchi, Noriko; Ishikawa, Satoru; Abe, Tadashi; Baba, Koji; Terada, Yasuko

2012-01-01

Heavy metals are transported to rice grains via the phloem. In rice nodes, the diffuse vascular bundles (DVBs), which enclose the enlarged elliptical vascular bundles (EVBs), are connected to the panicle and have a morphological feature that facilitates xylem-to-phloem transfer. To find a mechanism for restricting cadmium (Cd) transport into grains, the distribution of Cd, zinc (Zn), manganese (Mn), and sulphur (S) around the vascular bundles in node I (the node beneath the panicle) of Oryza sativa ‘Koshihikari’ were compared 1 week after heading. Elemental maps of Cd, Zn, Mn, and S in the vascular bundles of node I were obtained by synchrotron micro-X-ray fluorescence spectrometry and electron probe microanalysis. In addition, Cd K-edge microfocused X-ray absorption near-edge structure analyses were used to identify the elements co-ordinated with Cd. Both Cd and S were mainly distributed in the xylem of the EVB and in the parenchyma cell bridge (PCB) surrounding the EVB. Zn accumulated in the PCB, and Mn accumulated around the protoxylem of the EVB. Cd was co-ordinated mainly with S in the xylem of the EVB, but with both S and O in the phloem of the EVB and in the PCB. The EVB in the node retarded horizontal transport of Cd toward the DVB. By contrast, Zn was first stored in the PCB and then efficiently transferred toward the DVB. Our results provide evidence that transport of Cd, Zn, and Mn is differentially controlled in rice nodes, where vascular bundles are functionally interconnected. PMID:22291135

Partial axillary lymph node dissection inferior to the intercostobrachial nerves complements sentinel node biopsy in patients with clinically node-negative breast cancer.

PubMed

Li, Jianyi; Jia, Shi; Zhang, Wenhai; Qiu, Fang; Zhang, Yang; Gu, Xi; Xue, Jinqi

2015-06-30

The practice of breast cancer diagnosis and treatment in China varies to that in western developed countries. With the unavailability of radioactive tracer technique for sentinel lymph nodes biopsy (SLNB), using blue dye alone has been the only option in China. Also, the diagnosis of breast malignant tumor in most Chinese centres heavily relies on intraoperative instant frozen histology which is normally followed by sentinel lymph nodes mapping, SLNB and the potential breast and axillary operations in one consecutive session. This practice appears to cause a high false negative rate (FNR) for SLNB. The present study aimed to investigate the impact of the current practice in China on the accuracy of SLNB, and whether partial axillary lymph node dissection (PALND), dissection of lymph nodes inferior to the intercostobrachial nerve (ICBN), was a good complementary procedure following SLNB using blue dye. 289 patients with clinically node-negative breast cancer were identified and recruited. Tumorectomy, intraoperative instant frozen histological diagnosis, SLNB using methylene blue dye, and PALND or complete axillary node dissection (ALND) were performed in one consecutive operative session. The choice of SLNB only, SLNB followed by PALND or by ALND was based on the pre-determined protocol and preoperative choice by the patient. Clinical parameters were analyzed and survival analysis was performed. 37% patients with clinically negative nodes were found nodes positive. 59 patients with positive SLN underwent ALND, including 47 patients with up to two positive nodes which were all located inferior to the ICBN. 9 patients had failed SLNB and underwent PALND. Among them, 3 (33.3%) patients were found to have one metastatic node. 149 patients showed negative SLNB but chose PALND. Among them, 30 (20.1%), 14 (9.4) and 1 (0.7%) patients were found to have one, two and three metastatic node(s), respectively. PALND detected 48 (30.4%) patients who had either failed SLNB or negative SLNB to have additional positive nodes. All the patients with up to two positive nodes had their nodes located inferior to the ICBN. The FNR of SLNB was 43%. The accuracy rate was 58%. The follow-up ranged 12-33 months. The incidence of lymphedema for SLNB, PALND, and ALND was 0%, 0%, and 25.4%, respectively (P < 0.005). The disease-free survivals for SLNB, PALND, and ALND groups were 95.8%, 96.8%, and 94.9%, respectively (p > 0.05). Under the circumstances of current practice in China, PALND is a good complementary procedure following SLNB in clinically node-negative breast cancer.

Sentinel lymph node detection in patients with early cervical cancer.

PubMed

Acharya, B C; Jihong, L

2009-01-01

Lymph node status is the most important independent prognostic factor in early stage cervical cancer. Intraoperative lymphatic mapping and sentinel lymph node detection have been increasingly evaluated in the treatment of a variety of solid tumors, particularly breast cancer and cutaneous melanoma. This study evaluated the feasibility of these procedures in patients undergoing radical hysterectomy with pelvic lymphadenectomy for early cervical cancer. A total of 30 patients with histologically diagnosed FIGO stage IA to IIA cervical cancer were enrolled to this study. They were scheduled to undergo radical abdominal hysterectomy and pelvic lymphadenectomy after injecting patent blue dye in cervix. A total of 60 SLNs (mean 2.5) were detected in 24 patients with detection rate of 80%. Bilateral SLNs were detected in 70.1% of cases. SLNs were identified in obturator and external iliac areas in 50% and 31.7%, respectively; no SLNs were discovered in the common iliac region. Seven patients (23.3%) had lymph node metastases; one of these had false negative SLN.The false negative rate and negative predictive value were 14.3% and 94.4%, respectively. SLN detection procedure with blue dye technique is a feasible procedure in cervical cancer. Patent blue dye is cheap, safe and effective tracer to detect sentinel node in carcinoma of cervix.

Design of Deformation Monitoring System for Volcano Mitigation

NASA Astrophysics Data System (ADS)

Islamy, M. R. F.; Salam, R. A.; Munir, M. M.; Irsyam, M.; Khairurrijal

2016-08-01

Indonesia has many active volcanoes that are potentially disastrous. It needs good mitigation systems to prevent victims and to reduce casualties from potential disaster caused by volcanoes eruption. Therefore, the system to monitor the deformation of volcano was built. This system employed telemetry with the combination of Radio Frequency (RF) communications of XBEE and General Packet Radio Service (GPRS) communication of SIM900. There are two types of modules in this system, first is the coordinator as a parent and second is the node as a child. Each node was connected to coordinator forming a Wireless Sensor Network (WSN) with a star topology and it has an inclinometer based sensor, a Global Positioning System (GPS), and an XBEE module. The coordinator collects data to each node, one a time, to prevent collision data between nodes, save data to SD Card and transmit data to web server via GPRS. Inclinometer was calibrated with self-built in calibrator and tested in high temperature environment to check the durability. The GPS was tested by displaying its position in web server via Google Map Application Protocol Interface (API v.3). It was shown that the coordinator can receive and transmit data from every node to web server very well and the system works well in a high temperature environment.

Development and Implementation of Production Area of Agricultural Product Data Collection System Based on Embedded System

NASA Astrophysics Data System (ADS)

Xi, Lei; Guo, Wei; Che, Yinchao; Zhang, Hao; Wang, Qiang; Ma, Xinming

To solve problems in detecting the origin of agricultural products, this paper brings about an embedded data-based terminal, applies middleware thinking, and provides reusable long-range two-way data exchange module between business equipment and data acquisition systems. The system is constructed by data collection node and data center nodes. Data collection nodes taking embedded data terminal NetBoxII as the core, consisting of data acquisition interface layer, controlling information layer and data exchange layer, completing the data reading of different front-end acquisition equipments, and packing the data TCP to realize the data exchange between data center nodes according to the physical link (GPRS / CDMA / Ethernet). Data center node consists of the data exchange layer, the data persistence layer, and the business interface layer, which make the data collecting durable, and provide standardized data for business systems based on mapping relationship of collected data and business data. Relying on public communications networks, application of the system could establish the road of flow of information between the scene of origin certification and management center, and could realize the real-time collection, storage and processing between data of origin certification scene and databases of certification organization, and could achieve needs of long-range detection of agricultural origin.

[Sentinel node in melanoma and breast cancer. Current considerations].

PubMed

Vidal-Sicart, S; Vilalta Solsona, A; Alonso Vargas, M I

2015-01-01

The main objectives of sentinel node (SN) biopsy is to avoid unnecessary lymphadenectomies and to identify the 20-25% of patients with occult regional metastatic involvement. This technique reduces the associated morbidity from lymphadenectomy and increases the occult lymphatic metastases identification rate by offering the pathologist the or those lymph nodes with the highest probability of containing metastatic cells. Pre-surgical lymphoscintigraphy is considered a "road map" to guide the surgeon towards the sentinel nodes and to localize unpredictable lymphatic drainage patterns. The SPECT/CT advantages include a better SN detection rate than planar images, the ability to detect SNs in difficult to interpret studies, better SN depiction, especially in sites closer to the injection site and better anatomic localization. These advantages may result in a change in the patient's clinical management both in melanoma and breast cancer. The correct SN evaluation by pathology implies a tumoral load stratification and further prognostic implication. The use of intraoperative imaging devices allows the surgeon a better surgical approach and precise SN localization. Several studies reports the added value of such devices for more sentinel nodes excision and a complete monitoring of the whole procedure. New techniques, by using fluorescent or hybrid tracers, are currently being developed. Copyright © 2014 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

Biodistribution and radiation dosimetry of [64Cu]copper dichloride: first-in-human study in healthy volunteers.

PubMed

Avila-Rodriguez, M A; Rios, C; Carrasco-Hernandez, J; Manrique-Arias, J C; Martinez-Hernandez, R; García-Pérez, F O; Jalilian, A R; Martinez-Rodriguez, E; Romero-Piña, M E; Diaz-Ruiz, A

2017-12-12

In recent years, Copper-64 (T 1/2  = 12.7 h) in the chemical form of copper dichloride ([ 64 Cu]CuCl 2 ) has been identified as a potential agent for PET imaging and radionuclide therapy targeting the human copper transporter 1, which is overexpressed in a variety of cancer cells. Limited human biodistribution and radiation dosimetry data is available for this tracer. The aim of this research was to determine the biodistribution and estimate the radiation dosimetry of [ 64 Cu]CuCl 2 , using whole-body (WB) PET scans in healthy volunteers. Six healthy volunteers were included in this study (3 women and 3 men, mean age ± SD, 54.3 ± 8.6 years; mean weight ± SD, 77.2 ± 12.4 kg). After intravenous injection of the tracer (4.0 MBq/kg), three consecutive WB emission scans were acquired at 5, 30, and 60 min after injection. Additional scans were acquired at 5, 9, and 24 h post-injection. Low-dose CT scan without contrast was used for anatomic localization and attenuation correction. OLINDA/EXM software was used to calculate human radiation doses using the reference adult model. The highest uptake was in the liver, followed by lower and upper large intestine walls, and pancreas, in descending order. Urinary excretion was negligible. The critical organ was liver with a mean absorbed dose of 310 ± 67 μGy/MBq for men and 421 ± 56 μGy/MBq for women, while the mean WB effective doses were 51.2 ± 3.0 and 61.8 ± 5.2 μSv/MBq for men and women, respectively. To the best of our knowledge, this is the first report on biodistribution and radiation dosimetry of [ 64 Cu]CuCl 2 in healthy volunteers. Measured absorbed doses and effective doses are higher than previously reported doses estimated with biodistribution data from patients with prostate cancer, a difference that could be explained not just due to altered biodistribution in cancer patients compared to healthy volunteers but most likely due to the differences in the analysis technique and assumptions in the dose calculation.

Method for gathering and summarizing internet information

DOEpatents

Potok, Thomas E.; Elmore, Mark Thomas; Reed, Joel Wesley; Treadwell, Jim N.; Samatova, Nagiza Faridovna

2010-04-06

A computer method of gathering and summarizing large amounts of information comprises collecting information from a plurality of information sources (14, 51) according to respective maps (52) of the information sources (14), converting the collected information from a storage format to XML-language documents (26, 53) and storing the XML-language documents in a storage medium, searching for documents (55) according to a search query (13) having at least one term and identifying the documents (26) found in the search, and displaying the documents as nodes (33) of a tree structure (32) having links (34) and nodes (33) so as to indicate similarity of the documents to each other.

System for gathering and summarizing internet information

DOEpatents

Potok, Thomas E.; Elmore, Mark Thomas; Reed, Joel Wesley; Treadwell, Jim N.; Samatova, Nagiza Faridovna

2006-07-04

A computer method of gathering and summarizing large amounts of information comprises collecting information from a plurality of information sources (14, 51) according to respective maps (52) of the information sources (14), converting the collected information from a storage format to XML-language documents (26, 53) and storing the XML-language documents in a storage medium, searching for documents (55) according to a search query (13) having at least one term and identifying the documents (26) found in the search, and displaying the documents as nodes (33) of a tree structure (32) having links (34) and nodes (33) so as to indicate similarity of the documents to each other.

Method for gathering and summarizing internet information

DOEpatents

Potok, Thomas E [Oak Ridge, TN; Elmore, Mark Thomas [Oak Ridge, TN; Reed, Joel Wesley [Knoxville, TN; Treadwell, Jim N [Louisville, TN; Samatova, Nagiza Faridovna [Oak Ridge, TN

2008-01-01

A computer method of gathering and summarizing large amounts of information comprises collecting information from a plurality of information sources (14, 51) according to respective maps (52) of the information sources (14), converting the collected information from a storage format to XML-language documents (26, 53) and storing the XML-language documents in a storage medium, searching for documents (55) according to a search query (13) having at least one term and identifying the documents (26) found in the search, and displaying the documents as nodes (33) of a tree structure (32) having links (34) and nodes (33) so as to indicate similarity of the documents to each other.

Application of CPL with Interference Mapping Lithography to generate random contact reticle designs for the 65-nm node

NASA Astrophysics Data System (ADS)

Van Den Broeke, Douglas J.; Laidig, Thomas L.; Chen, J. Fung; Wampler, Kurt E.; Hsu, Stephen D.; Shi, Xuelong; Socha, Robert J.; Dusa, Mircea V.; Corcoran, Noel P.

2004-08-01

Imaging contact and via layers continues to be one of the major challenges to be overcome for 65nm node lithography. Initial results of using ASML MaskTools' CPL Technology to print contact arrays through pitch have demonstrated the potential to further extend contact imaging to a k1 near 0.30. While there are advantages and disadvantages for any potential RET, the benefits of not having to solve the phase assignment problem (which can lead to unresolvable phase conflicts), of it being a single reticle - single exposure technique, and its application to multiple layers within a device (clear field and dark field) make CPL an attractive, cost effective solution to low k1 imaging. However, real semiconductor circuit designs consist of much more than regular arrays of contact holes and a method to define the CPL reticle design for a full chip circuit pattern is required in order for this technique to be feasible in volume manufacturing. Interference Mapping Lithography (IML) is a novel approach for defining optimum reticle patterns based on the imaging conditions that will be used when the wafer is exposed. Figure 1 shows an interference map for an isolated contact simulated using ASML /1150 settings of 0.75NA and 0.92/0.72/30deg Quasar illumination. This technique provides a model-based approach for placing all types features (scattering bars, anti-scattering bars, non-printing assist features, phase shifted and non-phase shifted) for the purpose of enhancing the resolution of the target pattern and it can be applied to any reticle type including binary (COG), attenuated phase shifting mask (attPSM), alternating aperture phase shifting mask (altPSM), and CPL. In this work, we investigate the application of IML to generate CPL reticle designs for random contact patterns that are typical for 65nm node logic devices. We examine the critical issues related to using CPL with Interference Mapping Lithography including controlling side lobe printing, contact patterns with odd symmetry, forbidden pitch regions, and reticle manufacturing constraints. Multiple methods for deriving the interference map used to define reticle patterns for various RET's will be discussed. CPL reticle designs that were created from implementing automated algorithms for contact pattern decomposition using MaskWeaver will also be presented.

Studying Strategy Effects on Memory, Attitudes, and Intentions

ERIC Educational Resources Information Center

Roberts, Frank W.; Dansereau, Donald F.

2008-01-01

In this experiment, 175 participants generated node-link maps or summaries using multiple, massed, or ad lib schedules while reading text on stress-related information. They rated personal relevance immediately following studying and completed tests on the information and measures of attitudes and intentions 48 hours later. Low-verbal-ability…

Multi-Layered Feedforward Neural Networks for Image Segmentation

DTIC Science & Technology

1991-12-01

the Gram-Schmidt Network ...................... 80 xi Preface WILLIAM SHAKESPEARE 1564-1616 Is this a dagger which I see before me, The handle toward...any input-output mapping with a single hidden layer of non-linear nodes, the result may be like proving that a monkey could write Hamlet . Certainly it

Learning with Concept and Knowledge Maps: A Meta-Analysis

ERIC Educational Resources Information Center

Nesbit, John C.; Adesope, Olusola O.

2006-01-01

This meta-analysis reviews experimental and quasi-experimental studies in which students learned by constructing, modifying, or viewing node-link diagrams. Following an exhaustive search for studies meeting specified design criteria, 67 standardized mean difference effect sizes were extracted from 55 studies involving 5,818 participants. Students…

Partially pre-calculated weights for the backpropagation learning regime and high accuracy function mapping using continuous input RAM-based sigma-pi nets.

PubMed

Neville, R S; Stonham, T J; Glover, R J

2000-01-01

In this article we present a methodology that partially pre-calculates the weight updates of the backpropagation learning regime and obtains high accuracy function mapping. The paper shows how to implement neural units in a digital formulation which enables the weights to be quantised to 8-bits and the activations to 9-bits. A novel methodology is introduced to enable the accuracy of sigma-pi units to be increased by expanding their internal state space. We, also, introduce a novel means of implementing bit-streams in ring memories instead of utilising shift registers. The investigation utilises digital "Higher Order" sigma-pi nodes and studies continuous input RAM-based sigma-pi units. The units are trained with the backpropagation learning regime to learn functions to a high accuracy. The neural model is the sigma-pi units which can be implemented in digital microelectronic technology. The ability to perform tasks that require the input of real-valued information, is one of the central requirements of any cognitive system that utilises artificial neural network methodologies. In this article we present recent research which investigates a technique that can be used for mapping accurate real-valued functions to RAM-nets. One of our goals was to achieve accuracies of better than 1% for target output functions in the range Y epsilon [0,1], this is equivalent to an average Mean Square Error (MSE) over all training vectors of 0.0001 or an error modulus of 0.01. We present a development of the sigma-pi node which enables the provision of high accuracy outputs. The sigma-pi neural model was initially developed by Gurney (Learning in nets of structured hypercubes. PhD Thesis, Department of Electrical Engineering, Brunel University, Middlessex, UK, 1989; available as Technical Memo CN/R/144). Gurney's neuron models, the Time Integration Node (TIN), utilises an activation that was derived from a bit-stream. In this article we present a new methodology for storing sigma-pi node's activations as single values which are averages. In the course of the article we state what we define as a real number; how we represent real numbers and input of continuous values in our neural system. We show how to utilise the bounded quantised site-values (weights) of sigma-pi nodes to make training of these neurocomputing systems simple, using pre-calculated look-up tables to train the nets. In order to meet our accuracy goal, we introduce a means of increasing the bandwidth capability of sigma-pi units by expanding their internal state-space. In our implementation we utilise bit-streams when we calculate the real-valued outputs of the net. To simplify the hardware implementation of bit-streams we present a method of mapping them to RAM-based hardware using 'ring memories'. Finally, we study the sigma-pi units' ability to generalise once they are trained to map real-valued, high accuracy, continuous functions. We use sigma-pi units as they have been shown to have shorter training times than their analogue counterparts and can also overcome some of the drawbacks of semi-linear units (Gurney, 1992. Neural Networks, 5, 289-303).

Enhanced Peptide of Prostate Cancer Using Targeted Adenoviral Vectors

DTIC Science & Technology

2005-06-01

receptor subtype 2 has been constructed and evaluated in-human prostate cancer cells with regard to binding: of 64Cu - octreotide. In vivo experiments...of 64CU -octreotide.. The mice wer.e. sacrificed 1. h after peptide injection for biodistribution analysis. In vivo biodistribution studies showed...similar uptake of 64Cu - octreotide in both DU-145 and PC-3 tumors after infection with-AdSSTR2. (2.5. and 2.7% ID/g, respectively). This uptake was

Physicochemical stability, pharmacokinetic, and biodistribution evaluation of paclitaxel solid dispersion prepared using supercritical antisolvent process.

PubMed

Shanmugam, Srinivasan; Park, Jae-Hyun; Chi, Sang-Cheol; Yong, Chul Soon; Choi, Han-Gon; Woo, Jong Soo

2011-06-01

To investigate the physicochemical stability, pharmacokinetics (PK), and biodistribution of paclitaxel (PTX) from paclitaxel solid dispersion (PSD) prepared by supercritical antisolvent (SAS) process. Physicochemical stability was performed in accelerated (40°C 70 ± 5% RH) and stress (60°C) storage conditions for a period of 6 months and 4 weeks, respectively. PK and biodistribution studies were performed in rats following i.v. administration of PTX equivalent to 6 and 12 mg/kg formulations. Physical stability of PSD showed excellent stability with no recrystallization of the amorphous form. Chemical stability of PSD in terms of % PTX remaining was 98.2 ± 0.6% at 6 months and 97.9 ± 0.3% at 4 weeks of accelerated and stress conditions, respectively. The PK study showed a nonlinear increase in AUC with increasing dose, that is, 100% increase in dose (from 6 to 12 mg/kg) resulted in 405.90% increase in AUC. Unlike PK study, the organ distribution study of PTX from PSD showed linear relationship with dose escalation. The order of organ distribution of PTX from highest to lowest for both PSD and Taxol® was liver>kidney>lung>brain. This study demonstrated excellent physicochemical stability with insight information on the PK and biodistribution of PTX from PSD prepared by SAS process.

Preclinical Biodistribution and Safety Evaluation of a pbi-shRNA STMN1 Lipoplex after Subcutaneous Delivery.

PubMed

Wang, Zhaohui; Jay, Christopher M; Evans, Courtney; Kumar, Padmasini; Phalon, Connor; Rao, Donald D; Senzer, Neil; Nemunaitis, John

2017-02-01

Stathmin-1 (STMN1) is a microtubule-destabilizing protein which is overexpressed in cancer. Its overexpression is associated with poor prognosis and also serves as a predictive marker to taxane therapy. We have developed a proprietary bi-functional shRNA (bi-shRNA) platform to execute RNA interference (RNAi)-mediated gene silencing and a liposome-carrier complex to systemically deliver the pbi-shRNA plasmids. In vitro and in vivo testing demonstrated efficacy and specificity of pbi-shRNA plasmid in targeting STMN1 (Phadke, A. P., Jay, C. M., Wang, Z., Chen, S., Liu, S., Haddock, C., Kumar, P., Pappen, B. O., Rao, D. D., Templeton, N. S., et al. (2011). In vivo safety and antitumor efficacy of bifunctional small hairpin RNAs specific for the human Stathmin 1 oncoprotein. DNA Cell Biol. 30, 715-726.). Biodistribution and toxicology studies in bio-relevant Sprague Dawley rats with pbi-shRNA STMN1 lipoplex revealed that the plasmid DNA was delivered to a broad distribution of organs after a single subcutaneous injection. Specifically, plasmid was detected within the first week using QPCR (threshold 50 copies plasmid/1 µg genomic DNA) at the injection site, lung, spleen, blood, skin, ovary (limited), lymph nodes, and liver. It was not detected in the heart, testis or bone marrow. No plasmid was detected from any organ 30 days after injection. Treatment was well tolerated. Minimal inflammation/erythema was observed at the injection site. Circulating cytokine response was also examined by ELISA. The IL-6 levels were induced within 6 h then declined to the vehicle control level 72 h after the injection. TNFα induction was transiently observed 4 days after the DNA lipoplex treatment. In summary, the pbi-shRNA STMN1 lipoplex was well tolerated and displayed broad distribution after a single subcutaneous injection. The pre-clinical data has been filed to FDA and the pbi-shRNA STMN1 lipoplex is being investigated in a phase I clinical study. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Safety of methylene blue dye for lymphatic mapping in patients taking selective serotonin reuptake inhibitors.

PubMed

Shah-Khan, Miraj G; Lovely, Jenna; Degnim, Amy C

2012-11-01

Methylene blue dye has an important role in lymphatic mapping for sentinel lymph node surgery. A recent safety announcement from the US Food and Drug Administration warned physicians about possible serious central nervous system reactions in patients on serotonergic medications who received intravenous methylene blue for the identification of parathyroid glands. This report summarizes evidence from the Food and Drug Administration's announcement and methylene blue pharmacokinetics. The authors conclude that the use of methylene blue dye at low doses for lymphatic mapping likely carries very little risk for serotonin neurotoxicity, although breast surgeons should be aware of this potential complication in the event of mental status or neuromuscular changes in patients after lymphatic mapping. Copyright © 2012 Elsevier Inc. All rights reserved.

DNA nanomapping using CRISPR-Cas9 as a programmable nanoparticle.

PubMed

Mikheikin, Andrey; Olsen, Anita; Leslie, Kevin; Russell-Pavier, Freddie; Yacoot, Andrew; Picco, Loren; Payton, Oliver; Toor, Amir; Chesney, Alden; Gimzewski, James K; Mishra, Bud; Reed, Jason

2017-11-21

Progress in whole-genome sequencing using short-read (e.g., <150 bp), next-generation sequencing technologies has reinvigorated interest in high-resolution physical mapping to fill technical gaps that are not well addressed by sequencing. Here, we report two technical advances in DNA nanotechnology and single-molecule genomics: (1) we describe a labeling technique (CRISPR-Cas9 nanoparticles) for high-speed AFM-based physical mapping of DNA and (2) the first successful demonstration of using DVD optics to image DNA molecules with high-speed AFM. As a proof of principle, we used this new "nanomapping" method to detect and map precisely BCL2-IGH translocations present in lymph node biopsies of follicular lymphoma patents. This HS-AFM "nanomapping" technique can be complementary to both sequencing and other physical mapping approaches.

Comparison of Node-Centered and Cell-Centered Unstructured Finite-Volume Discretizations: Viscous Fluxes

NASA Technical Reports Server (NTRS)

Diskin, Boris; Thomas, James L.; Nielsen, Eric J.; Nishikawa, Hiroaki; White, Jeffery A.

2010-01-01

Discretization of the viscous terms in current finite-volume unstructured-grid schemes are compared using node-centered and cell-centered approaches in two dimensions. Accuracy and complexity are studied for four nominally second-order accurate schemes: a node-centered scheme and three cell-centered schemes - a node-averaging scheme and two schemes with nearest-neighbor and adaptive compact stencils for least-square face gradient reconstruction. The grids considered range from structured (regular) grids to irregular grids composed of arbitrary mixtures of triangles and quadrilaterals, including random perturbations of the grid points to bring out the worst possible behavior of the solution. Two classes of tests are considered. The first class of tests involves smooth manufactured solutions on both isotropic and highly anisotropic grids with discontinuous metrics, typical of those encountered in grid adaptation. The second class concerns solutions and grids varying strongly anisotropically over a curved body, typical of those encountered in high-Reynolds number turbulent flow simulations. Tests from the first class indicate the face least-square methods, the node-averaging method without clipping, and the node-centered method demonstrate second-order convergence of discretization errors with very similar accuracies per degree of freedom. The tests of the second class are more discriminating. The node-centered scheme is always second order with an accuracy and complexity in linearization comparable to the best of the cell-centered schemes. In comparison, the cell-centered node-averaging schemes may degenerate on mixed grids, have a higher complexity in linearization, and can fail to converge to the exact solution when clipping of the node-averaged values is used. The cell-centered schemes using least-square face gradient reconstruction have more compact stencils with a complexity similar to that of the node-centered scheme. For simulations on highly anisotropic curved grids, the least-square methods have to be amended either by introducing a local mapping based on a distance function commonly available in practical schemes or modifying the scheme stencil to reflect the direction of strong coupling. The major conclusion is that accuracies of the node centered and the best cell-centered schemes are comparable at equivalent number of degrees of freedom.

Anatomic Distribution of Fluorodeoxyglucose-Avid Para-aortic Lymph Nodes in Patients With Cervical Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takiar, Vinita; Fontanilla, Hiral P.; Eifel, Patricia J.

Purpose: Conformal treatment of para-aortic lymph nodes (PAN) in cervical cancer allows dose escalation and reduces normal tissue toxicity. Currently, data documenting the precise location of involved PAN are lacking. We define the spatial distribution of this high-risk nodal volume by analyzing fluorodeoxyglucose (FDG)-avid lymph nodes (LNs) on positron emission tomography/computed tomography (PET/CT) scans in patients with cervical cancer. Methods and Materials: We identified 72 PANs on pretreatment PET/CT of 30 patients with newly diagnosed stage IB-IVA cervical cancer treated with definitive chemoradiation. LNs were classified as left-lateral para-aortic (LPA), aortocaval (AC), or right paracaval (RPC). Distances from the LNmore » center to the closest vessel and adjacent vertebral body were calculated. Using deformable image registration, nodes were mapped to a template computed tomogram to provide a visual impression of nodal frequencies and anatomic distribution. Results: We identified 72 PET-positive para-aortic lymph nodes (37 LPA, 32 AC, 3 RPC). All RPC lymph nodes were in the inferior third of the para-aortic region. The mean distance from aorta for all lymph nodes was 8.3 mm (range, 3-17 mm), and from the inferior vena cava was 5.6 mm (range, 2-10 mm). Of the 72 lymph nodes, 60% were in the inferior third, 36% were in the middle third, and 4% were in the upper third of the para-aortic region. In all, 29 of 30 patients also had FDG-avid pelvic lymph nodes. Conclusions: A total of 96% of PET positive nodes were adjacent to the aorta; PET positive nodes to the right of the IVC were rare and were all located distally, within 3 cm of the aortic bifurcation. Our findings suggest that circumferential margins around the vessels do not accurately define the nodal region at risk. Instead, the anatomical extent of the nodal basin should be contoured on each axial image to provide optimal coverage of the para-aortic nodal compartment.« less

Subserosal uterine injection of blue dye for the identification of the sentinel node in patients with endometrial cancer: a feasibility study.

PubMed

Biliatis, Ioannis; Thomakos, Nikolaos; Koutroumpa, Ioanna; Haidopoulos, Dimitris; Sotiropoulou, Maria; Antsaklis, Aris; Vlachos, George; Akrivos, Nikolaos; Rodolakis, Alexandros

2017-09-01

To define the detection rate, sensitivity, and negative predictive value (NPV) of the sentinel node technique in patients with endometrial cancer. Patients with endometrial cancer after informed consent underwent subserosal injection of blue dye during hysterectomy in a tertiary gynae/oncology department between 2010 and 2014. The procedure was performed in all cases by the same team including two gynae/oncologist consultants and one trainee. All relevant perioperative clinicopathological characteristics of the population were recorded prospectively. The identified sentinel nodes were removed separately and a completion bilateral pelvic lymphadenectomy followed in all cases. Simple statistics were used to calculate the sensitivity and NPV of the method on per patient basis. Fifty-four patients were included in this study. At least one sentinel node was mapped in 46 patients yielding a detection rate of 85.2%. Bilateral detection of sentinel nodes was accomplished in only 31 patients (57.4%). The mean number of sentinel nodes was 2.6 per patient and the commonest site of identification was the external iliac artery and vein area (66%). Six patients (11%) had a positive lymph node, and in five of them, this was the sentinel one yielding a sensitivity of 83.3% and an NPV of 97.5%. The overall detection rate improved significantly after the first 15 cases; however, this was not the case for the bilateral detection rate. Our study is in accordance with previous studies of sentinel node in endometrial cancer and further demonstrates and enhances the confidence in the technique. In the current era of an ongoing debate on whether a systematic lymphadenectomy in patients with endometrial cancer is still necessary, we believe that the sentinel node is an acceptable alternative and should be applied routinely in tertiary centres following a strict algorithm.

Integrating geophysical data for mapping the contamination of industrial sites by polycyclic aromatic hydrocarbons: A geostatistical approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Colin, P.; Nicoletis, S.; Froidevaux, R.

1996-12-31

A case study is presented of building a map showing the probability that the concentration in polycyclic aromatic hydrocarbon (PAH) exceeds a critical threshold. This assessment is based on existing PAH sample data (direct information) and on an electrical resistivity survey (indirect information). Simulated annealing is used to build a model of the range of possible values for PAH concentrations and of the bivariate relationship between PAH concentrations and electrical resistivity. The geostatistical technique of simple indicator kriging is then used, together with the probabilistic model, to infer, at each node of a grid, the range of possible values whichmore » the PAH concentration can take. The risk map is then extracted for this characterization of the local uncertainty. The difference between this risk map and a traditional iso-concentration map is then discussed in terms of decision-making.« less

Network modelling methods for FMRI.

PubMed

Smith, Stephen M; Miller, Karla L; Salimi-Khorshidi, Gholamreza; Webster, Matthew; Beckmann, Christian F; Nichols, Thomas E; Ramsey, Joseph D; Woolrich, Mark W

2011-01-15

There is great interest in estimating brain "networks" from FMRI data. This is often attempted by identifying a set of functional "nodes" (e.g., spatial ROIs or ICA maps) and then conducting a connectivity analysis between the nodes, based on the FMRI timeseries associated with the nodes. Analysis methods range from very simple measures that consider just two nodes at a time (e.g., correlation between two nodes' timeseries) to sophisticated approaches that consider all nodes simultaneously and estimate one global network model (e.g., Bayes net models). Many different methods are being used in the literature, but almost none has been carefully validated or compared for use on FMRI timeseries data. In this work we generate rich, realistic simulated FMRI data for a wide range of underlying networks, experimental protocols and problematic confounds in the data, in order to compare different connectivity estimation approaches. Our results show that in general correlation-based approaches can be quite successful, methods based on higher-order statistics are less sensitive, and lag-based approaches perform very poorly. More specifically: there are several methods that can give high sensitivity to network connection detection on good quality FMRI data, in particular, partial correlation, regularised inverse covariance estimation and several Bayes net methods; however, accurate estimation of connection directionality is more difficult to achieve, though Patel's τ can be reasonably successful. With respect to the various confounds added to the data, the most striking result was that the use of functionally inaccurate ROIs (when defining the network nodes and extracting their associated timeseries) is extremely damaging to network estimation; hence, results derived from inappropriate ROI definition (such as via structural atlases) should be regarded with great caution. Copyright © 2010 Elsevier Inc. All rights reserved.

LEGION: Lightweight Expandable Group of Independently Operating Nodes

NASA Technical Reports Server (NTRS)

Burl, Michael C.

2012-01-01

LEGION is a lightweight C-language software library that enables distributed asynchronous data processing with a loosely coupled set of compute nodes. Loosely coupled means that a node can offer itself in service to a larger task at any time and can withdraw itself from service at any time, provided it is not actively engaged in an assignment. The main program, i.e., the one attempting to solve the larger task, does not need to know up front which nodes will be available, how many nodes will be available, or at what times the nodes will be available, which is normally the case in a "volunteer computing" framework. The LEGION software accomplishes its goals by providing message-based, inter-process communication similar to MPI (message passing interface), but without the tight coupling requirements. The software is lightweight and easy to install as it is written in standard C with no exotic library dependencies. LEGION has been demonstrated in a challenging planetary science application in which a machine learning system is used in closed-loop fashion to efficiently explore the input parameter space of a complex numerical simulation. The machine learning system decides which jobs to run through the simulator; then, through LEGION calls, the system farms those jobs out to a collection of compute nodes, retrieves the job results as they become available, and updates a predictive model of how the simulator maps inputs to outputs. The machine learning system decides which new set of jobs would be most informative to run given the results so far; this basic loop is repeated until sufficient insight into the physical system modeled by the simulator is obtained.

A Stochastic Inversion Method for Potential Field Data: Ant Colony Optimization

NASA Astrophysics Data System (ADS)

Liu, Shuang; Hu, Xiangyun; Liu, Tianyou

2014-07-01

Simulating natural ants' foraging behavior, the ant colony optimization (ACO) algorithm performs excellently in combinational optimization problems, for example the traveling salesman problem and the quadratic assignment problem. However, the ACO is seldom used to inverted for gravitational and magnetic data. On the basis of the continuous and multi-dimensional objective function for potential field data optimization inversion, we present the node partition strategy ACO (NP-ACO) algorithm for inversion of model variables of fixed shape and recovery of physical property distributions of complicated shape models. We divide the continuous variables into discrete nodes and ants directionally tour the nodes by use of transition probabilities. We update the pheromone trails by use of Gaussian mapping between the objective function value and the quantity of pheromone. It can analyze the search results in real time and promote the rate of convergence and precision of inversion. Traditional mapping, including the ant-cycle system, weaken the differences between ant individuals and lead to premature convergence. We tested our method by use of synthetic data and real data from scenarios involving gravity and magnetic anomalies. The inverted model variables and recovered physical property distributions were in good agreement with the true values. The ACO algorithm for binary representation imaging and full imaging can recover sharper physical property distributions than traditional linear inversion methods. The ACO has good optimization capability and some excellent characteristics, for example robustness, parallel implementation, and portability, compared with other stochastic metaheuristics.

In vivo degeneration and the fate of inorganic nanoparticles.

PubMed

Feliu, Neus; Docter, Dominic; Heine, Markus; Del Pino, Pablo; Ashraf, Sumaira; Kolosnjaj-Tabi, Jelena; Macchiarini, Paolo; Nielsen, Peter; Alloyeau, Damien; Gazeau, Florence; Stauber, Roland H; Parak, Wolfgang J

2016-05-03

What happens to inorganic nanoparticles (NPs), such as plasmonic gold or silver, superparamagnetic iron oxide, or fluorescent quantum dot NPs after they have been administrated to a living being? This review discusses the integrity, biodistribution, and fate of NPs after in vivo administration. The hybrid nature of the NPs is described, conceptually divided into the inorganic core, the engineered surface coating comprising of the ligand shell and optionally also bio-conjugates, and the corona of adsorbed biological molecules. Empirical evidence shows that all of these three compounds may degrade individually in vivo and can drastically modify the life cycle and biodistribution of the whole heterostructure. Thus, the NPs may be decomposed into different parts, whose biodistribution and fate would need to be analyzed individually. Multiple labeling and quantification strategies for such a purpose will be discussed. All reviewed data indicate that NPs in vivo should no longer be considered as homogeneous entities, but should be seen as inorganic/organic/biological nano-hybrids with complex and intricately linked distribution and degradation pathways.

Biodistribution and catabolism of 18F-labelled isopeptide N(epsilon)-(gamma-glutamyl)-L-lysine.

PubMed

Hultsch, C; Bergmann, R; Pawelke, B; Pietzsch, J; Wuest, F; Johannsen, B; Henle, T

2005-12-01

Isopeptide bonds between the epsilon-amino group of lysine and the gamma-carboxamide group of glutamine are formed during strong heating of pure proteins or, more important, by enzymatic reaction mediated by transglutaminases. Despite the wide use of a microbial transglutaminase in food biotechnology, up to now little is known about the metabolic fate of the isopeptide N(epsilon)-(gamma-glutamyl)-L-lysine. In the present study, N-succinimidyl-4-[(18)F]fluorobenzoate was used to modify N(epsilon)-(gamma-glutamyl)-L-lysine at each of its two alpha-amino groups, resulting in the 4-[(18)F]fluorobenzoylated derivatives, for which biodistribution, catabolism, and elimination were investigated in male Wistar rats. A significant different biochemical behavior of the two labelled isopeptides was observed in terms of in vitro stability, in vivo metabolism as well as biodistribution. The results suggest that the metabolic fate of isopeptides is likely to be dependent on how they are reabsorbed - free or peptide bound.

Use of direct fluorescence labeling and confocal microscopy to determine the biodistribution of two protein therapeutics, Cerezyme and Ceredase.

PubMed

Piepenhagen, Peter A; Vanpatten, Scott; Hughes, Heather; Waire, James; Murray, James; Andrews, Laura; Edmunds, Tim; O'Callaghan, Michael; Thurberg, Beth L

2010-07-01

Efficient targeting of therapeutic reagents to tissues and cell types of interest is critical to achieving therapeutic efficacy and avoiding unwanted side effects due to offtarget uptake. To increase assay efficiency and reduce the number of animals used per experiment during preclinical development, we used a combination of direct fluorescence labeling and confocal microscopy to simultaneously examine the biodistribution of two therapeutic proteins, Cerezyme and Ceredase, in the same animals. We show that the fluorescent tags do not interfere with protein uptake and localization. We are able to detect Cerezyme and Ceredase in intact cells and organs and demonstrate colocalization within target cells using confocal microscopy. In addition, the relative amount of protein internalized by different cell types can be quantified using cell type-specific markers and morphometric analysis. This approach provides an easy and straightforward means of assessing the tissue and cell type-specific biodistribution of multiple protein therapeutics in target organs using a minimal number of animals. (c) 2009 Wiley-Liss, Inc.

Pharmacokinetics and Biodistribution of the Illegal Food Colorant Rhodamine B in Rats.

PubMed

Cheng, Yung-Yi; Tsai, Tung-Hu

2017-02-08

The International Agency for Research on Cancer (IARC) demonstrated rhodamine B as a potential carcinogen in 1978. Nevertheless, rhodamine B has been illegally used as a colorant in food in many countries. Few pharmacokinetic and toxicological investigations have been performed since the first pharmacokinetic study on rhodamine B in 1961. The aims of this study were to develop a simple and sensitive high-performance liquid chromatography method with fluorescence detection for the quantitative detection of rhodamine B in the plasma and organs of rats and to estimate its pharmacokinetics and biodistribution. The results demonstrated that the oral bioavailabilities of rhodamine B were 28.3 and 9.8% for the low-dose and high-dose exposures, respectively. Furthermore, rhodamine B was highly accumulated in the liver and, to a lesser extent, the kidney, but was undetectable in the brain. These results provide useful information for improving the pharmacokinetics and biodistribution of rhodamine B, supporting additional food safety evaluations.

Preparing Students for Future Learning with Teachable Agents

ERIC Educational Resources Information Center

Chin, Doris B.; Dohmen, Ilsa M.; Cheng, Britte H.; Oppezzo, Marily A.; Chase, Catherine C.; Schwartz, Daniel L.

2010-01-01

Over the past several years, the authors have been developing an instructional technology, called Teachable Agents (TA), which draws on the social metaphor of teaching to help students learn. Students teach a computer character, their "agent," by creating a concept map of nodes connected by qualitative causal links. The authors hypothesize that…

Wireless Sensor Node Data Gathering and Location Mapping

DTIC Science & Technology

2012-03-01

adaptive two-phase approach to WiFi location sensing,” 4 th Int. Conf. on Pervasive Computing and Communications Workshops, Pisa, Italy, 2006, pp. 452...wrt.v24_micro_generic.bin, March 2010. [11] P. Asadoorian and L. Pesce, Linksys WRT54G Ultimate Hacking , Burlington, MA: Syngress, 2007, pp. 25. 32

Mapping Sequence performed during the STS-120 R-Bar Pitch Maneuver

NASA Image and Video Library

2007-10-25

ISS016-E-005926 (25 Oct. 2007) --- A close-up view of the Harmony node in the payload bay of Space Shuttle Discovery is provided by this image photographed by an Expedition 16 crewmember during a backflip maneuver performed by the approaching visitors (STS-120) to the International Space Station.

Model of brain activation predicts the neural collective influence map of the brain

PubMed Central

Morone, Flaviano; Roth, Kevin; Min, Byungjoon; Makse, Hernán A.

2017-01-01

Efficient complex systems have a modular structure, but modularity does not guarantee robustness, because efficiency also requires an ingenious interplay of the interacting modular components. The human brain is the elemental paradigm of an efficient robust modular system interconnected as a network of networks (NoN). Understanding the emergence of robustness in such modular architectures from the interconnections of its parts is a longstanding challenge that has concerned many scientists. Current models of dependencies in NoN inspired by the power grid express interactions among modules with fragile couplings that amplify even small shocks, thus preventing functionality. Therefore, we introduce a model of NoN to shape the pattern of brain activations to form a modular environment that is robust. The model predicts the map of neural collective influencers (NCIs) in the brain, through the optimization of the influence of the minimal set of essential nodes responsible for broadcasting information to the whole-brain NoN. Our results suggest intervention protocols to control brain activity by targeting influential neural nodes predicted by network theory. PMID:28351973

A scale-free systems theory of motivation and addiction.

PubMed

Chambers, R Andrew; Bickel, Warren K; Potenza, Marc N

2007-01-01

Scale-free organizations, characterized by uneven distributions of linkages between nodal elements, describe the structure and function of many life-based complex systems developing under evolutionary pressures. We explore motivated behavior as a scale-free map toward a comprehensive translational theory of addiction. Motivational and behavioral repertoires are reframed as link and nodal element sets, respectively, comprising a scale-free structure. These sets are generated by semi-independent information-processing streams within cortical-striatal circuits that cooperatively provide decision-making and sequential processing functions necessary for traversing maps of motivational links connecting behavioral nodes. Dopamine modulation of cortical-striatal plasticity serves a central-hierarchical mechanism for survival-adaptive sculpting and development of motivational-behavioral repertoires by guiding a scale-free design. Drug-induced dopamine activity promotes drug taking as a highly connected behavioral hub at the expense of natural-adaptive motivational links and behavioral nodes. Conceptualizing addiction as pathological alteration of scale-free motivational-behavioral repertoires unifies neurobiological, neurocomputational and behavioral research while addressing addiction vulnerability in adolescence and psychiatric illness. This model may inform integrative research in defining more effective prevention and treatment strategies for addiction.

A Scale-Free Systems Theory of Motivation and Addiction

PubMed Central

Bickel, Warren K.; Potenza, Marc N.

2007-01-01

Scale-free organizations, characterized by uneven distributions of linkages between nodal elements, describe the structure and function of many life-based complex systems developing under evolutionary pressures. We explore motivated behavior as a scale-free map toward a comprehensive translational theory of addiction. Motivational and behavioral repertoires are reframed as link and nodal element sets, respectively, comprising a scale-free structure. These sets are generated by semi-independent information-processing streams within cortical-striatal circuits that cooperatively provide decision-making and sequential processing functions necessary for traversing maps of motivational links connecting behavioral nodes. Dopamine modulation of cortical-striatal plasticity serves a central-hierarchical mechanism for survival-adaptive sculpting and development of motivational-behavioral repertoires by guiding a scale-free design. Drug-induced dopamine activity promotes drug-taking as a highly connected behavioral hub at the expense of natural-adaptive motivational links and behavioral nodes. Conceptualizing addiction as pathological alteration of scale-free motivational-behavioral repertoires unifies neurobiological, neurocomputational and behavioral research while addressing addiction vulnerability in adolescence and psychiatric illness. This model may inform integrative research in defining more effective prevention and treatment strategies for addiction. PMID:17574673

A finite element method to correct deformable image registration errors in low-contrast regions

NASA Astrophysics Data System (ADS)

Zhong, Hualiang; Kim, Jinkoo; Li, Haisen; Nurushev, Teamour; Movsas, Benjamin; Chetty, Indrin J.

2012-06-01

Image-guided adaptive radiotherapy requires deformable image registration to map radiation dose back and forth between images. The purpose of this study is to develop a novel method to improve the accuracy of an intensity-based image registration algorithm in low-contrast regions. A computational framework has been developed in this study to improve the quality of the ‘demons’ registration. For each voxel in the registration's target image, the standard deviation of image intensity in a neighborhood of this voxel was calculated. A mask for high-contrast regions was generated based on their standard deviations. In the masked regions, a tetrahedral mesh was refined recursively so that a sufficient number of tetrahedral nodes in these regions can be selected as driving nodes. An elastic system driven by the displacements of the selected nodes was formulated using a finite element method (FEM) and implemented on the refined mesh. The displacements of these driving nodes were generated with the ‘demons’ algorithm. The solution of the system was derived using a conjugated gradient method, and interpolated to generate a displacement vector field for the registered images. The FEM correction method was compared with the ‘demons’ algorithm on the computed tomography (CT) images of lung and prostate patients. The performance of the FEM correction relating to the ‘demons’ registration was analyzed based on the physical property of their deformation maps, and quantitatively evaluated through a benchmark model developed specifically for this study. Compared to the benchmark model, the ‘demons’ registration has the maximum error of 1.2 cm, which can be corrected by the FEM to 0.4 cm, and the average error of the ‘demons’ registration is reduced from 0.17 to 0.11 cm. For the CT images of lung and prostate patients, the deformation maps generated by the ‘demons’ algorithm were found unrealistic at several places. In these places, the displacement differences between the ‘demons’ registrations and their FEM corrections were found in the range of 0.4 and 1.1 cm. The mesh refinement and FEM simulation were implemented in a single thread application which requires about 45 min of computation time on a 2.6 GHz computer. This study has demonstrated that the FEM can be integrated with intensity-based image registration algorithms to improve their registration accuracy, especially in low-contrast regions.

New surface radiolabeling schemes of super paramagnetic iron oxide nanoparticles (SPIONs) for biodistribution studies

NASA Astrophysics Data System (ADS)

Nallathamby, Prakash D.; Mortensen, Ninell P.; Palko, Heather A.; Malfatti, Mike; Smith, Catherine; Sonnett, James; Doktycz, Mitchel J.; Gu, Baohua; Roeder, Ryan K.; Wang, Wei; Retterer, Scott T.

2015-04-01

Nanomaterial based drug delivery systems allow for the independent tuning of the surface chemical and physical properties that affect their biodistribution in vivo and the therapeutic payloads that they are intended to deliver. Additionally, the added therapeutic and diagnostic value of their inherent material properties often provides extra functionality. Iron based nanomaterials with their magnetic properties and easily tailorable surface chemistry are of particular interest as model systems. In this study the core radius of the iron oxide nanoparticles (NPs) was 14.08 +/- 3.92 nm while the hydrodynamic radius of the NPs, as determined by Dynamic Light Scattering (DLS), was between 90-110 nm. In this study, different approaches were explored to create radiolabeled NPs that are stable in solution. The NPs were functionalized with polycarboxylate or polyamine surface functional groups. Polycarboxylate functionalized NPs had a zeta potential of -35 mV and polyamine functionalized NPs had a zeta potential of +40 mV. The polycarboxylate functionalized NPs were chosen for in vivo biodistribution studies and hence were radiolabeled with 14C, with a final activity of 0.097 nCi mg-1 of NPs. In chronic studies, the biodistribution profile is tracked using low level radiolabeled proxies of the nanoparticles of interest. Conventionally, these radiolabeled proxies are chemically similar but not chemically identical to the non-radiolabeled NPs of interest. This study is novel as different approaches were explored to create radiolabeled NPs that are stable, possess a hydrodynamic radius of <100 nm and most importantly they exhibit an identical surface chemical functionality as their non-radiolabeled counterparts. Identical chemical functionality of the radiolabeled probes to the non-radiolabeled probes was an important consideration to generate statistically similar biodistribution data sets using multiple imaging and detection techniques. The radiolabeling approach described here is applicable to the synthesis of a large class of nanomaterials with multiple core and surface functionalities. This work combined with the biodistribution data suggests that the radiolabeling schemes carried out in this study have broad implications for use in pharmacokinetic studies for a variety of nanomaterials.Nanomaterial based drug delivery systems allow for the independent tuning of the surface chemical and physical properties that affect their biodistribution in vivo and the therapeutic payloads that they are intended to deliver. Additionally, the added therapeutic and diagnostic value of their inherent material properties often provides extra functionality. Iron based nanomaterials with their magnetic properties and easily tailorable surface chemistry are of particular interest as model systems. In this study the core radius of the iron oxide nanoparticles (NPs) was 14.08 +/- 3.92 nm while the hydrodynamic radius of the NPs, as determined by Dynamic Light Scattering (DLS), was between 90-110 nm. In this study, different approaches were explored to create radiolabeled NPs that are stable in solution. The NPs were functionalized with polycarboxylate or polyamine surface functional groups. Polycarboxylate functionalized NPs had a zeta potential of -35 mV and polyamine functionalized NPs had a zeta potential of +40 mV. The polycarboxylate functionalized NPs were chosen for in vivo biodistribution studies and hence were radiolabeled with 14C, with a final activity of 0.097 nCi mg-1 of NPs. In chronic studies, the biodistribution profile is tracked using low level radiolabeled proxies of the nanoparticles of interest. Conventionally, these radiolabeled proxies are chemically similar but not chemically identical to the non-radiolabeled NPs of interest. This study is novel as different approaches were explored to create radiolabeled NPs that are stable, possess a hydrodynamic radius of <100 nm and most importantly they exhibit an identical surface chemical functionality as their non-radiolabeled counterparts. Identical chemical functionality of the radiolabeled probes to the non-radiolabeled probes was an important consideration to generate statistically similar biodistribution data sets using multiple imaging and detection techniques. The radiolabeling approach described here is applicable to the synthesis of a large class of nanomaterials with multiple core and surface functionalities. This work combined with the biodistribution data suggests that the radiolabeling schemes carried out in this study have broad implications for use in pharmacokinetic studies for a variety of nanomaterials. Electronic supplementary information (ESI) available: (S1) High-Resolution Transmission Electron Microscopy (HRTEM) image of iron oxide nanoparticles, (S2) Superconducting Quantum Interference Device (SQUID) measurement of magnetization of super paramagnetic iron oxide nanoparticles, (S3) Fourier Transform Infrared Spectroscopy (FT-IR) spectra of Fe-Si-COO- synthesised using Grignard reagents (S4) FT-IR spectra of iron oxide nanoparticles silanized with commercially available N-[(3-Trimethoxysilyl)propyl]ethylenediamine triacetic acid tripotassium salt, (S5) Synthesis of hyperbranched amine functionalized iron oxide nanoparticles from amino propyl triethyl silane functionalized iron nanoparticles using ethyleneimine as an initiator and polymerizing agent. See DOI: 10.1039/c4nr06441k

Multiple network alignment via multiMAGNA+.

PubMed

Vijayan, Vipin; Milenkovic, Tijana

2017-08-21

Network alignment (NA) aims to find a node mapping that identifies topologically or functionally similar network regions between molecular networks of different species. Analogous to genomic sequence alignment, NA can be used to transfer biological knowledge from well- to poorly-studied species between aligned network regions. Pairwise NA (PNA) finds similar regions between two networks while multiple NA (MNA) can align more than two networks. We focus on MNA. Existing MNA methods aim to maximize total similarity over all aligned nodes (node conservation). Then, they evaluate alignment quality by measuring the amount of conserved edges, but only after the alignment is constructed. Directly optimizing edge conservation during alignment construction in addition to node conservation may result in superior alignments. Thus, we present a novel MNA method called multiMAGNA++ that can achieve this. Indeed, multiMAGNA++ outperforms or is on par with existing MNA methods, while often completing faster than existing methods. That is, multiMAGNA++ scales well to larger network data and can be parallelized effectively. During method evaluation, we also introduce new MNA quality measures to allow for more fair MNA method comparison compared to the existing alignment quality measures. MultiMAGNA++ code is available on the method's web page at http://nd.edu/~cone/multiMAGNA++/.

Tumor differentiation as related to sentinel lymph node status in gastric cancer

PubMed Central

Lavy, Ron; Kapiev, Andronik; Hershkovitz, Yehuda; Poluksht, Natan; Rabin, Igor; Chikman, Bar; Shapira, Zahar; Wasserman, Ilan; Sandbank, Judith; Halevy, Ariel

2014-01-01

AIM: To investigate the influence of tumor grade on sentinel lymph node (SLN) status in patients with gastric cancer (GC). METHODS: We retrospectively studied 71 patients with GC who underwent SLN mapping during gastric surgery to evaluate the relationship between SLN status and tumor grade. RESULTS: Poorly differentiated tumors were detected in 50/71 patients, while the other 21 patients had moderately differentiated tumors. SLNs were identified in 58/71 patients (82%). In 41 of the 58 patients that were found to have stained nodes (70.7%), the tumor was of the poorly differentiated type (group I), while in the remaining patients with stained nodes 17/58 (29.3%), the tumor was of the moderately differentiated type (group II). Positive SLNs were found in 22/41 patients in group I (53.7%) and in 7/17 patients in group II (41.2%) (P = 0.325). The rate of positivity for the SLNs in the two groups (53.7% vs 41.2%) was not statistically significant (P = 0.514). CONCLUSION: Most of our patients were found to have poorly differentiated adenocarcinoma of the stomach and there was no correlation between tumor grade and SLN involvement. PMID:24627734

Systems Biology Graphical Notation: Process Description language Level 1 Version 1.3.

PubMed

Moodie, Stuart; Le Novère, Nicolas; Demir, Emek; Mi, Huaiyu; Villéger, Alice

2015-09-04

The Systems Biological Graphical Notation (SBGN) is an international community effort for standardized graphical representations of biological pathways and networks. The goal of SBGN is to provide unambiguous pathway and network maps for readers with different scientific backgrounds as well as to support efficient and accurate exchange of biological knowledge between different research communities, industry, and other players in systems biology. Three SBGN languages, Process Description (PD), Entity Relationship (ER) and Activity Flow (AF), allow for the representation of different aspects of biological and biochemical systems at different levels of detail. The SBGN Process Description language represents biological entities and processes between these entities within a network. SBGN PD focuses on the mechanistic description and temporal dependencies of biological interactions and transformations. The nodes (elements) are split into entity nodes describing, e.g., metabolites, proteins, genes and complexes, and process nodes describing, e.g., reactions and associations. The edges (connections) provide descriptions of relationships (or influences) between the nodes, such as consumption, production, stimulation and inhibition. Among all three languages of SBGN, PD is the closest to metabolic and regulatory pathways in biological literature and textbooks, but its well-defined semantics offer a superior precision in expressing biological knowledge.

The Label Matters: μPET Imaging of the Biodistribution of Low Molar Mass 89Zr and 18F-Labeled Poly(2-ethyl-2-oxazoline).

PubMed

Glassner, Mathias; Palmieri, Luca; Monnery, Bryn D; Verbrugghen, Thomas; Deleye, Steven; Stroobants, Sigrid; Staelens, Steven; Wyffels, Leonie; Hoogenboom, Richard

2017-01-09

Poly(2-alkyl-2-oxazoline)s (PAOx) have received increasing interest for biomedical applications. Therefore, it is of fundamental importance to gain an in-depth understanding of the biodistribution profile of PAOx. We report the biodistribution of poly(2-ethyl-2-oxazoline) (PEtOx) with a molar mass of 5 kDa radiolabeled with PET isotopes 89 Zr and 18 F. 18 F-labeled PEtOx is prepared by the strain-promoted azide-alkyne cycloaddition (SPAAC) of [ 18 F]fluoroethylazide to bicyclo[6.1.0]non-4-yne (BCN)-functionalized PEtOx as many common labeling strategies were found to be unsuccessful for PEtOx. 89 Zr-labeled PEtOx is prepared using desferrioxamine end-groups as a chelator. Five kDa PEtOx shows a significantly faster blood clearance compared to PEtOx of higher molar mass while uptake in the liver is lower, indicating a minor contribution of the liver in excretion of the 5 kDa PEtOx. While [ 18 F]-PEtOx displays a rapid and efficient clearance from the kidneys, 5 kDa [ 89 Zr]-Df-PEtOx is not efficiently cleared over the time course of the study, which is most likely caused by trapping of 89 Zr-labeled metabolites in the renal tubules and not the polymer itself, demonstrating the importance of selecting the appropriate label for biodistribution studies.

The Comparison of Biodistribution, Efficacy and Toxicity of Two PEGylated Liposomal Doxorubicin Formulations in Mice Bearing C-26 Colon Carcinoma: a Preclinical Study.

PubMed

Razavi-Azarkhiavi, K; Jafarian, A H; Abnous, K; Razavi, B M; Shirani, K; Zeinali, M; Jaafari, M R; Karimi, G

2016-06-01

Over the past several years, the considerable attention has been progressively given to liposomal formulations of anthracyclines. SinaDoxosome(®) (Exir Nano Sina Company, Iran) is a pegylated liposomal doxorubicin (DOX) which approved by Food and Drug Administration of IRAN for treatment of some types of cancer. The aim of this study was to compare the biodistribution, efficacy, cardiotoxicity and hepatotoxicity of SinaDoxosome(®) with Caelyx(®) in mice bearing C-26 colon carcinoma. Mice tumor size evaluation during the experimental period (28 days) showed comparable therapeutic efficacy of nano-formulations. The biodistribution studies showed no significant difference in DOX tissue concentration between Caelyx(®) and SinaDoxosome(®). DOX induced-ECG changes were not detected in nano-formulations. No significant alteration was found in biochemical indexes of myocardial injury in mice exposed to nano-formulations in comparison with control mice. The tissue oxidative parameters such as lipid peroxidation, glutathione, catalase and superoxide dismutase was significantly changed as the results of free DOX treatment. However, the oxidative status of Caelyx(®) and SinaDoxosome(®) treated animals did not showed any changes. The experiment also revealed that apoptotic pathway was not activated in the heart of mice exposed to nano-formulations. Although this investigation showed that Caelyx(®) and SinaDoxosome(®) are similar in terms of biodistribution, efficacy and toxicity, appropriate clinical evaluations in patients should be considered. © Georg Thieme Verlag KG Stuttgart · New York.

Lactoferrin-modified rotigotine nanoparticles for enhanced nose-to-brain delivery: LESA-MS/MS-based drug biodistribution, pharmacodynamics, and neuroprotective effects

PubMed Central

Bi, Chenchen; Duan, Dongyu; Chu, Liuxiang; Yu, Xin; Wu, Zimei; Wang, Aiping; Sun, Kaoxiang

2018-01-01

Introduction Efficient delivery of rotigotine into the brain is crucial for obtaining maximum therapeutic efficacy for Parkinson’s disease (PD). Therefore, in the present study, we prepared lactoferrin-modified rotigotine nanoparticles (Lf-R-NPs) and studied their biodistribution, pharmacodynamics, and neuroprotective effects following nose-to-brain delivery in the rat 6-hydroxydopamine model of PD. Materials and methods The biodistribution of rotigotine nanoparticles (R-NPs) and Lf-R-NPs after intranasal administration was assessed by liquid extraction surface analysis coupled with tandem mass spectrometry. Contralateral rotations were quantified to evaluate pharmacodynamics. Tyrosine hydroxylase and dopamine transporter immunohistochemistry were performed to compare the neuroprotective effects of levodopa, R-NPs, and Lf-R-NPs. Results Liquid extraction surface analysis coupled with tandem mass spectrometry analysis, used to examine rotigotine biodistribution, showed that Lf-R-NPs more efficiently supplied rotigotine to the brain (with a greater sustained amount of the drug delivered to this organ, and with more effective targeting to the striatum) than R-NPs. The pharmacodynamic study revealed a significant difference (P<0.05) in contralateral rotations between rats treated with Lf-R-NPs and those treated with R-NPs. Furthermore, Lf-R-NPs significantly alleviated nigrostriatal dopaminergic neurodegeneration in the rat model of 6-hydroxydopamine-induced PD. Conclusion Our findings show that Lf-R-NPs deliver rotigotine more efficiently to the brain, thereby enhancing efficacy. Therefore, Lf-R-NPs might have therapeutic potential for the treatment of PD. PMID:29391788

Lactoferrin-modified rotigotine nanoparticles for enhanced nose-to-brain delivery: LESA-MS/MS-based drug biodistribution, pharmacodynamics, and neuroprotective effects.

PubMed

Yan, Xiuju; Xu, Lixiao; Bi, Chenchen; Duan, Dongyu; Chu, Liuxiang; Yu, Xin; Wu, Zimei; Wang, Aiping; Sun, Kaoxiang

2018-01-01

Efficient delivery of rotigotine into the brain is crucial for obtaining maximum therapeutic efficacy for Parkinson's disease (PD). Therefore, in the present study, we prepared lactoferrin-modified rotigotine nanoparticles (Lf-R-NPs) and studied their biodistribution, pharmacodynamics, and neuroprotective effects following nose-to-brain delivery in the rat 6-hydroxydopamine model of PD. The biodistribution of rotigotine nanoparticles (R-NPs) and Lf-R-NPs after intranasal administration was assessed by liquid extraction surface analysis coupled with tandem mass spectrometry. Contralateral rotations were quantified to evaluate pharmacodynamics. Tyrosine hydroxylase and dopamine transporter immunohistochemistry were performed to compare the neuroprotective effects of levodopa, R-NPs, and Lf-R-NPs. Liquid extraction surface analysis coupled with tandem mass spectrometry analysis, used to examine rotigotine biodistribution, showed that Lf-R-NPs more efficiently supplied rotigotine to the brain (with a greater sustained amount of the drug delivered to this organ, and with more effective targeting to the striatum) than R-NPs. The pharmacodynamic study revealed a significant difference ( P <0.05) in contralateral rotations between rats treated with Lf-R-NPs and those treated with R-NPs. Furthermore, Lf-R-NPs significantly alleviated nigrostriatal dopaminergic neurodegeneration in the rat model of 6-hydroxydopamine-induced PD. Our findings show that Lf-R-NPs deliver rotigotine more efficiently to the brain, thereby enhancing efficacy. Therefore, Lf-R-NPs might have therapeutic potential for the treatment of PD.

Topological data analysis of contagion maps for examining spreading processes on networks.

PubMed

Taylor, Dane; Klimm, Florian; Harrington, Heather A; Kramár, Miroslav; Mischaikow, Konstantin; Porter, Mason A; Mucha, Peter J

2015-07-21

Social and biological contagions are influenced by the spatial embeddedness of networks. Historically, many epidemics spread as a wave across part of the Earth's surface; however, in modern contagions long-range edges-for example, due to airline transportation or communication media-allow clusters of a contagion to appear in distant locations. Here we study the spread of contagions on networks through a methodology grounded in topological data analysis and nonlinear dimension reduction. We construct 'contagion maps' that use multiple contagions on a network to map the nodes as a point cloud. By analysing the topology, geometry and dimensionality of manifold structure in such point clouds, we reveal insights to aid in the modelling, forecast and control of spreading processes. Our approach highlights contagion maps also as a viable tool for inferring low-dimensional structure in networks.

Topological data analysis of contagion maps for examining spreading processes on networks

NASA Astrophysics Data System (ADS)

Taylor, Dane; Klimm, Florian; Harrington, Heather A.; Kramár, Miroslav; Mischaikow, Konstantin; Porter, Mason A.; Mucha, Peter J.

2015-07-01

Social and biological contagions are influenced by the spatial embeddedness of networks. Historically, many epidemics spread as a wave across part of the Earth's surface; however, in modern contagions long-range edges--for example, due to airline transportation or communication media--allow clusters of a contagion to appear in distant locations. Here we study the spread of contagions on networks through a methodology grounded in topological data analysis and nonlinear dimension reduction. We construct `contagion maps' that use multiple contagions on a network to map the nodes as a point cloud. By analysing the topology, geometry and dimensionality of manifold structure in such point clouds, we reveal insights to aid in the modelling, forecast and control of spreading processes. Our approach highlights contagion maps also as a viable tool for inferring low-dimensional structure in networks.

Group percolation in interdependent networks

NASA Astrophysics Data System (ADS)

Wang, Zexun; Zhou, Dong; Hu, Yanqing

2018-03-01

In many real network systems, nodes usually cooperate with each other and form groups to enhance their robustness to risks. This motivates us to study an alternative type of percolation, group percolation, in interdependent networks under attack. In this model, nodes belonging to the same group survive or fail together. We develop a theoretical framework for this group percolation and find that the formation of groups can improve the resilience of interdependent networks significantly. However, the percolation transition is always of first order, regardless of the distribution of group sizes. As an application, we map the interdependent networks with intersimilarity structures, which have attracted much attention recently, onto the group percolation and confirm the nonexistence of continuous phase transitions.

A Critical Review on the Use of Support Values in Tree Viewers and Bioinformatics Toolkits.

PubMed

Czech, Lucas; Huerta-Cepas, Jaime; Stamatakis, Alexandros

2017-06-01

Phylogenetic trees are routinely visualized to present and interpret the evolutionary relationships of species. Most empirical evolutionary data studies contain a visualization of the inferred tree with branch support values. Ambiguous semantics in tree file formats can lead to erroneous tree visualizations and therefore to incorrect interpretations of phylogenetic analyses. Here, we discuss problems that arise when displaying branch values on trees after rerooting. Branch values are typically stored as node labels in the widely-used Newick tree format. However, such values are attributes of branches. Storing them as node labels can therefore yield errors when rerooting trees. This depends on the mostly implicit semantics that tools deploy to interpret node labels. We reviewed ten tree viewers and ten bioinformatics toolkits that can display and reroot trees. We found that 14 out of 20 of these tools do not permit users to select the semantics of node labels. Thus, unaware users might obtain incorrect results when rooting trees. We illustrate such incorrect mappings for several test cases and real examples taken from the literature. This review has already led to improvements in eight tools. We suggest tools should provide options that explicitly force users to define the semantics of node labels. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Adaptive Bio-Inspired Wireless Network Routing for Planetary Surface Exploration

NASA Technical Reports Server (NTRS)

Alena, Richard I.; Lee, Charles

2004-01-01

Wireless mobile networks suffer connectivity loss when used in a terrain that has hills, and valleys when line of sight is interrupted or range is exceeded. To resolve this problem and achieve acceptable network performance, we have designed an adaptive, configurable, hybrid system to automatically route network packets along the best path between multiple geographically dispersed modules. This is very useful in planetary surface exploration, especially for ad-hoc mobile networks, where computational devices take an active part in creating a network infrastructure, and can actually be used to route data dynamically and even store data for later transmission between networks. Using inspiration from biological systems, this research proposes to use ant trail algorithms with multi-layered information maps (topographic maps, RF coverage maps) to determine the best route through ad-hoc network at real time. The determination of best route is a complex one, and requires research into the appropriate metrics, best method to identify the best path, optimizing traffic capacity, network performance, reliability, processing capabilities and cost. Real ants are capable of finding the shortest path from their nest to a food source without visual sensing through the use of pheromones. They are also able to adapt to changes in the environment using subtle clues. To use ant trail algorithms, we need to define the probability function. The artificial ant is, in this case, a software agent that moves from node to node on a network graph. The function to calculate the fitness (evaluate the better path) includes: length of the network edge, the coverage index, topology graph index, and pheromone trail left behind by other ant agents. Each agent modifies the environment in two different ways: 1) Local trail updating: As the ant moves between nodes it updates the amount of pheromone on the edge; and 2) Global trail updating: When all ants have completed a tour the ant that found the shortest route updates the edges in its path.

Astronomy In The Cloud: Using Mapreduce For Image Coaddition

NASA Astrophysics Data System (ADS)

Wiley, Keith; Connolly, A.; Gardner, J.; Krughoff, S.; Balazinska, M.; Howe, B.; Kwon, Y.; Bu, Y.

2011-01-01

In the coming decade, astronomical surveys of the sky will generate tens of terabytes of images and detect hundreds of millions of sources every night. The study of these sources will involve computational challenges such as anomaly detection, classification, and moving object tracking. Since such studies require the highest quality data, methods such as image coaddition, i.e., registration, stacking, and mosaicing, will be critical to scientific investigation. With a requirement that these images be analyzed on a nightly basis to identify moving sources, e.g., asteroids, or transient objects, e.g., supernovae, these datastreams present many computational challenges. Given the quantity of data involved, the computational load of these problems can only be addressed by distributing the workload over a large number of nodes. However, the high data throughput demanded by these applications may present scalability challenges for certain storage architectures. One scalable data-processing method that has emerged in recent years is MapReduce, and in this paper we focus on its popular open-source implementation called Hadoop. In the Hadoop framework, the data is partitioned among storage attached directly to worker nodes, and the processing workload is scheduled in parallel on the nodes that contain the required input data. A further motivation for using Hadoop is that it allows us to exploit cloud computing resources, i.e., platforms where Hadoop is offered as a service. We report on our experience implementing a scalable image-processing pipeline for the SDSS imaging database using Hadoop. This multi-terabyte imaging dataset provides a good testbed for algorithm development since its scope and structure approximate future surveys. First, we describe MapReduce and how we adapted image coaddition to the MapReduce framework. Then we describe a number of optimizations to our basic approach and report experimental results compring their performance. This work is funded by the NSF and by NASA.

Using Social Media and Mobile Devices to Discover and Share Disaster Data Products Derived From Satellites

NASA Technical Reports Server (NTRS)

Mandl, Daniel; Cappelaere, Patrice; Frye, Stuart; Evans, John; Moe, Karen

2014-01-01

Data products derived from Earth observing satellites are difficult to find and share without specialized software and often times a highly paid and specialized staff. For our research effort, we endeavored to prototype a distributed architecture that depends on a standardized communication protocol and applications program interface (API) that makes it easy for anyone to discover and access disaster related data. Providers can easily supply the public with their disaster related products by building an adapter for our API. Users can use the API to browse and find products that relate to the disaster at hand, without a centralized catalogue, for example floods, and then are able to share that data via social media. Furthermore, a longerterm goal for this architecture is to enable other users who see the shared disaster product to be able to generate the same product for other areas of interest via simple point and click actions on the API on their mobile device. Furthermore, the user will be able to edit the data with on the ground local observations and return the updated information to the original repository of this information if configured for this function. This architecture leverages SensorWeb functionality [1] presented at previous IGARSS conferences. The architecture is divided into two pieces, the frontend, which is the GeoSocial API, and the backend, which is a standardized disaster node that knows how to talk to other disaster nodes, and also can communicate with the GeoSocial API. The GeoSocial API, along with the disaster node basic functionality enables crowdsourcing and thus can leverage insitu observations by people external to a group to perform tasks such as improving water reference maps, which are maps of existing water before floods. This can lower the cost of generating precision water maps. Keywords-Data Discovery, Disaster Decision Support, Disaster Management, Interoperability, CEOS WGISS Disaster Architecture

Near-infrared fluorescence sentinel lymph node mapping in breast cancer: a multicenter experience

PubMed Central

Verbeek, Floris P.R.; Troyan, Susan L.; Mieog, J. Sven D.; Liefers, Gerrit-Jan; Moffitt, Lorissa A.; Rosenberg, Mireille; Hirshfield-Bartek, Judith; Gioux, Sylvain; van de Velde, Cornelis J.H.; Vahrmeijer, Alexander L.; Frangioni, John V.

2014-01-01

NIR fluorescence imaging using indocyanine green (ICG) has the potential to improve the SLN procedure by facilitating percutaneous and intraoperative identification of lymphatic channels and SLNs. Previous studies suggested that a dose of 0.62 mg (1.6 ml of 0.5 mM) ICG is optimal for SLN mapping in breast cancer. The aim of this study was to evaluate the diagnostic accuracy of near-infrared (NIR) fluorescence for sentinel lymph node (SLN) mapping in breast cancer patients when used in conjunction with conventional techniques. Study subjects were 95 breast cancer patients planning to undergo SLN procedure at either the Dana-Farber/Harvard Cancer Center (Boston, MA, USA) or the Leiden University Medical Center (Leiden, the Netherlands) between July 2010 and January 2013. Subjects underwent the standard-of-care SLN procedure at each institution using 99Technetium-colloid in all subjects and patent blue in 27 (28%) of the subjects. NIR fluorescence-guided SLN detection was performed using the Mini-FLARE imaging system. SLN identification was successful in 94 of 95 subjects (99%) using NIR fluorescence imaging or a combination of both NIR fluorescence imaging and radioactive guidance. In 2 of 95 subjects, radioactive guidance was necessary for initial in vivo identification of SLNs. In 1 of 95 subjects, NIR fluorescence was necessary for initial in vivo identification of SLNs. A total of 177 SLNs (mean = 1.9, range = 1–5) were resected: 100% NIR fluorescent, 88% radioactive, and 78% (of 40 nodes) blue. In 2 of 95 subjects (2.1%), SLNs containing macrometastases were found only by NIR fluorescence, and in 1 patient this led to upstaging to N1. This study demonstrates the safe and accurate application of NIR fluorescence imaging for the identification of SLNs in breast cancer patients, but calls into question what technique should be used as the gold standard in future studies. PMID:24337507

Fat water decomposition using globally optimal surface estimation (GOOSE) algorithm.

PubMed

Cui, Chen; Wu, Xiaodong; Newell, John D; Jacob, Mathews

2015-03-01

This article focuses on developing a novel noniterative fat water decomposition algorithm more robust to fat water swaps and related ambiguities. Field map estimation is reformulated as a constrained surface estimation problem to exploit the spatial smoothness of the field, thus minimizing the ambiguities in the recovery. Specifically, the differences in the field map-induced frequency shift between adjacent voxels are constrained to be in a finite range. The discretization of the above problem yields a graph optimization scheme, where each node of the graph is only connected with few other nodes. Thanks to the low graph connectivity, the problem is solved efficiently using a noniterative graph cut algorithm. The global minimum of the constrained optimization problem is guaranteed. The performance of the algorithm is compared with that of state-of-the-art schemes. Quantitative comparisons are also made against reference data. The proposed algorithm is observed to yield more robust fat water estimates with fewer fat water swaps and better quantitative results than other state-of-the-art algorithms in a range of challenging applications. The proposed algorithm is capable of considerably reducing the swaps in challenging fat water decomposition problems. The experiments demonstrate the benefit of using explicit smoothness constraints in field map estimation and solving the problem using a globally convergent graph-cut optimization algorithm. © 2014 Wiley Periodicals, Inc.

Monitoring the Earth System Grid Federation through the ESGF Dashboard

NASA Astrophysics Data System (ADS)

Fiore, S.; Bell, G. M.; Drach, B.; Williams, D.; Aloisio, G.

2012-12-01

The Climate Model Intercomparison Project, phase 5 (CMIP5) is a global effort coordinated by the World Climate Research Programme (WCRP) involving tens of modeling groups spanning 19 countries. It is expected the CMIP5 distributed data archive will total upwards of 3.5 petabytes, stored across several ESGF Nodes on four continents (North America, Europe, Asia, and Australia). The Earth System Grid Federation (ESGF) provides the IT infrastructure to support the CMIP5. In this regard, the monitoring of the distributed ESGF infrastructure represents a crucial part carried out by the ESGF Dashboard. The ESGF Dashboard is a software component of the ESGF stack, responsible for collecting key information about the status of the federation in terms of: 1) Network topology (peer-groups composition), 2) Node type (host/services mapping), 3) Registered users (including their Identity Providers), 4) System metrics (e.g., round-trip time, service availability, CPU, memory, disk, processes, etc.), 5) Download metrics (both at the Node and federation level). The last class of information is very important since it provides a strong insight of the CMIP5 experiment: the data usage statistics. In this regard, CMCC and LLNL have developed a data analytics management system for the analysis of both node-level and federation-level data usage statistics. It provides data usage statistics aggregated by project, model, experiment, variable, realm, peer node, time, ensemble, datasetname (including version), etc. The back-end of the system is able to infer the data usage information of the entire federation, by carrying out: - at node level: a 18-step reconciliation process on the peer node databases (i.e. node manager and publisher DB) which provides a 15-dimension datawarehouse with local statistics and - at global level: an aggregation process which federates the data usage statistics into a 16-dimension datawarehouse with federation-level data usage statistics. The front-end of the Dashboard system exploits a web desktop approach, which joins the pervasivity of a web application with the flexibility of a desktop one.

Endothelial protein kinase MAP4K4 promotes vascular inflammation and atherosclerosis

PubMed Central

Roth Flach, Rachel J.; Skoura, Athanasia; Matevossian, Anouch; Danai, Laura V.; Zheng, Wei; Cortes, Christian; Bhattacharya, Samit K.; Aouadi, Myriam; Hagan, Nana; Yawe, Joseph C.; Vangala, Pranitha; Menendez, Lorena Garcia; Cooper, Marcus P.; Fitzgibbons, Timothy P.; Buckbinder, Leonard; Czech, Michael P.

2015-01-01

Signalling pathways that control endothelial cell (EC) permeability, leukocyte adhesion and inflammation are pivotal for atherosclerosis initiation and progression. Here we demonstrate that the Sterile-20-like mitogen-activated protein kinase kinase kinase kinase 4 (MAP4K4), which has been implicated in inflammation, is abundantly expressed in ECs and in atherosclerotic plaques from mice and humans. On the basis of endothelial-specific MAP4K4 gene silencing and gene ablation experiments in Apoe−/− mice, we show that MAP4K4 in ECs markedly promotes Western diet-induced aortic macrophage accumulation and atherosclerotic plaque development. Treatment of Apoe−/− and Ldlr−/− mice with a selective small-molecule MAP4K4 inhibitor also markedly reduces atherosclerotic lesion area. MAP4K4 silencing in cultured ECs attenuates cell surface adhesion molecule expression while reducing nuclear localization and activity of NFκB, which is critical for promoting EC activation and atherosclerosis. Taken together, these results reveal that MAP4K4 is a key signalling node that promotes immune cell recruitment in atherosclerosis. PMID:26688060

Sentinel node biopsy and concomitant probe-guided tumor excision of nonpalpable breast cancer.

PubMed

van Rijk, Maartje C; Tanis, Pieter J; Nieweg, Omgo E; Loo, Claudette E; Olmos, Renato A Valdés; Oldenburg, Hester S A; Rutgers, Emiel J Th; Hoefnagel, Cornelis A; Kroon, Bin B R

2007-02-01

Preliminary data have shown encouraging results of a single intratumoral radiopharmaceutical injection that enables both sentinel node biopsy and probe-guided excision of the primary tumor in patients with nonpalpable breast cancer. The aim of the study was to evaluate this approach in a large group of patients. Lymphoscintigraphy was performed in 368 patients with nonpalpable breast cancer after intratumoral injection of (99m)Tc-nanocolloid (.2 mL, 123 MBq, 3.3 mCi) guided by ultrasound or stereotaxis. The sentinel node was pursued with the aid of vital blue dye (1.0 mL, intratumoral) and a gamma ray detection probe. In case of breast-conserving surgery, the probe was used to guide the excision. At least one sentinel node could be identified intraoperatively in 357 patients (97%), of whom 69 had involved nodes (19%). Age over 60 years was associated with less frequent nonaxillary lymphatic drainage and absence of internal mammary chain dissemination. Tumor-free margins were obtained in 262 (89%) of the 293 patients who underwent segmental excision. Re-excision of the primary tumor bed was performed in six patients (2%). During a median follow-up of 22 months, one breast recurrence and one axillary recurrence were observed. Lymphatic mapping and probe-guided tumor excision of nonpalpable breast cancer by intralesional administration of a single dose of (99m)Tc-nanocolloid and blue dye resulted in 97% identification of the sentinel node and in tumor-free margins in 89% of the patients who underwent breast-conserving surgery. Longer follow-up is needed to substantiate the accuracy and safety of this technique.

A study on uterine lymphatic anatomy for standardization of pelvic sentinel lymph node detection in endometrial cancer.

PubMed

Geppert, Barbara; Lönnerfors, Céline; Bollino, Michele; Arechvo, Anastasija; Persson, Jan

2017-05-01

To describe the anatomy of uterine lymphatic drainage following cervical or fundal tracer injection to enable standardization of a pelvic sentinel lymph node (SLN) concept in endometrial cancer (EC). A prospective consecutive study of women with EC was conducted. A fluorescent dye (Indocyanine green) was injected into the cervix (n=60) or the uterine fundus (n=30). A systematic trans- and retroperitoneal mapping of uterine lymphatic drainage was performed. Positions of the pelvic SLNs, defined by afferent lymph vessels, and lymph node metastases were compared. Two consistent lymphatic pathways with pelvic SLNs were identified irrespective of injection site; an upper paracervical pathway (UPP) with draining medial external and/or obturator lymph nodes and a lower paracervical pathway (LPP) with draining internal iliac and/or presacral lymph nodes. Bilateral display of at least one pelvic pathway following cervical and fundal injection occurred in 98% and 80% respectively (p=0.005). Bilateral display of both pelvic pathways occurred in 30% and 20% respectively (p=0.6) as the LPP was less often displayed. Nearly one third of the 19% node positive patients had metastases along the LPP. No false negative SLNs were identified. Based on uterine lymphatic anatomy a bilateral detection of at least one SLN in both the UPP and LPP should be aimed for. Absence of display of the LPP may warrant a full presacral lymphadenectomy. Although pelvic pathways and positions of SLNs are independent of the tracer injection site, cervical injection is preferable due to a higher technical success rate. Copyright © 2017 Elsevier Inc. All rights reserved.

A Parallel Multiclassification Algorithm for Big Data Using an Extreme Learning Machine.

PubMed

Duan, Mingxing; Li, Kenli; Liao, Xiangke; Li, Keqin

2018-06-01

As data sets become larger and more complicated, an extreme learning machine (ELM) that runs in a traditional serial environment cannot realize its ability to be fast and effective. Although a parallel ELM (PELM) based on MapReduce to process large-scale data shows more efficient learning speed than identical ELM algorithms in a serial environment, some operations, such as intermediate results stored on disks and multiple copies for each task, are indispensable, and these operations create a large amount of extra overhead and degrade the learning speed and efficiency of the PELMs. In this paper, an efficient ELM based on the Spark framework (SELM), which includes three parallel subalgorithms, is proposed for big data classification. By partitioning the corresponding data sets reasonably, the hidden layer output matrix calculation algorithm, matrix decomposition algorithm, and matrix decomposition algorithm perform most of the computations locally. At the same time, they retain the intermediate results in distributed memory and cache the diagonal matrix as broadcast variables instead of several copies for each task to reduce a large amount of the costs, and these actions strengthen the learning ability of the SELM. Finally, we implement our SELM algorithm to classify large data sets. Extensive experiments have been conducted to validate the effectiveness of the proposed algorithms. As shown, our SELM achieves an speedup on a cluster with ten nodes, and reaches a speedup with 15 nodes, an speedup with 20 nodes, a speedup with 25 nodes, a speedup with 30 nodes, and a speedup with 35 nodes.

Influence maximization in complex networks through optimal percolation

NASA Astrophysics Data System (ADS)

Morone, Flaviano; Makse, Hernan; CUNY Collaboration; CUNY Collaboration

The whole frame of interconnections in complex networks hinges on a specific set of structural nodes, much smaller than the total size, which, if activated, would cause the spread of information to the whole network, or, if immunized, would prevent the diffusion of a large scale epidemic. Localizing this optimal, that is, minimal, set of structural nodes, called influencers, is one of the most important problems in network science. Here we map the problem onto optimal percolation in random networks to identify the minimal set of influencers, which arises by minimizing the energy of a many-body system, where the form of the interactions is fixed by the non-backtracking matrix of the network. Big data analyses reveal that the set of optimal influencers is much smaller than the one predicted by previous heuristic centralities. Remarkably, a large number of previously neglected weakly connected nodes emerges among the optimal influencers. Reference: F. Morone, H. A. Makse, Nature 524,65-68 (2015)

ImmunoPET Imaging of Insulin-Like Growth Factor 1 Receptor in a Subcutaneous Mouse Model of Pancreatic Cancer

DTIC Science & Technology

2016-06-30

In addition, 89Zr-labeled nonspecific human IgG (89Zr-Df-IgG) displayed minimal uptake in IGF-1R positive MIA PaCa-2 tumor xenografts (3.63 ± 0.95...scanning using the LI-COR Odyssey Infrared Imaging System (LI-COR Biosciences, Lincoln, NE, USA). Human Pancreatic Adenocarcinoma Xenograft Mouse Model...biodistribution was performed to confirm the PET ROI data. The biodistribution of 89Zr-Df-1A2G11 was compared between the xenograft -bearing mice (Figure 6

In vivo lymph node mapping by Cadmium Tellurium quantum dots in rats.

PubMed

Si, Chengshuai; Zhang, Yunpeng; Lv, Xianbo; Yang, Wuli; Ran, Zhipeng; Sun, Peng

2014-12-01

Intraoperative lymph node mapping (LNM) is highly significant for many surgeries in patients with cancer. Many types of tracers are currently used, but the ideal method has not yet been identified. We aimed to identify a stable lymphatic drainage pathway in an animal model and compared the effects of quantum dots (QD), a new fluorescent tracer, with those of methylene blue in intraoperative LNM. Indian ink (0.2 mL) was subcutaneously injected into the plantar metatarsal regions of six Sprague-Dawley rats. After 2 wk of incubation and subsequent dissection, the potentially stained LNs were examined pathologically to identify the lymphatic drainage pathway. After applying anesthesia, 0.1 mL methylene blue (2%) and QD (1 mg/mL) were injected into the plantar metatarsal regions of six rats for intraoperative LNM. The QD group was observed with a near-infrared imaging system, and the methylene blue group was directly observed. Drainages were recorded at 5, 10, 30, 60, and 120 min and at 1 d. Two three-level drainage pathways, that is, a peripheral drainage (popliteal LNs, inguinal LNs, and axillary LNs) and a central drainage (popliteal lymph node [LN], iliac LN, and renal LN) pathways were identified. Both methylene blue and QD stained the sentinel lymph node (SLNs) quickly, but methylene blue was difficult to identify in the deep tissues and the LNs beyond the SLN. Furthermore, the blue-stained LNs remain dyed for only 2 h. In contrast, the QDs exhibited high target-to-background ratios in both the SLNs and the following LNs. Additionally, the fluorescence lasted from 5 min-1 d after injection. An ideal lymphatic drainage model was found. QDs are excellent tracers for intraoperative LNM compared with methylene blue. Near infrared fluorescent imaging is a promising LNM method for clinical practice. Copyright © 2014 Elsevier Inc. All rights reserved.

Lymph node dissection technique is more important than lymph node count in identifying nodal metastases in radical cystectomy patients: a comparative mapping study.

PubMed

Dorin, Ryan P; Daneshmand, Siamak; Eisenberg, Manuel S; Chandrasoma, Shahin; Cai, Jie; Miranda, Gus; Nichols, Peter W; Skinner, Donald G; Skinner, Eila C

2011-11-01

The value of lymph node dissection (LND) in the treatment of bladder urothelial carcinoma is well established. However, standards for the quality of LND remain controversial. We compared the distribution of lymph node (LN) metastases in a two-institution cohort of patients undergoing radical cystectomy (RC) using a uniformly applied extended LND template. Patients undergoing RC at the University of Southern California (USC) Institute of Urology and at Oregon Health Sciences University (OHSU) were included if they met the following criteria: (1) no prior pelvic radiotherapy or LND; (2) lymphatic tissue submitted from all nine predesignated regions, including the paracaval and para-aortic LNs; (3) bladder primary; and (4) category M0 disease. The number and location of LN metastases were prospectively entered into corresponding databases. LN maps were constructed and correlated with preoperative and pathologic characteristics. Kaplan-Meier curves were constructed to estimate overall survival (OS) and recurrence free survival (RFS) among LN-positive (LN+) patients. Inclusion criteria were met by 646 patients (439 USC, 207 OHSU), and 23% had LN metastases at time of cystectomy. Although there was a difference in the median per-patient LN count between institutions, there were no significant interinstitutional differences in the incidence or distribution of positive LNs, which were found in 11% of patients with ≤pT2b and in 44% of patients with ≥pT3a tumors. Among LN+ patients, 41% had positive LNs above the common iliac bifurcation. Estimated 5-yr RFS and OS rates for LN+ patients were 45% and 33%, respectively, and did not differ significantly between institutions. LN metastases in regions outside the boundaries of standard LND are common. Adherence to meticulous dissection technique within an extended template is likely more important than total LN count for achieving optimal oncologic outcomes. Copyright © 2011 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Comparing Single-Site and Multiport Robotic Hysterectomy with Sentinel Lymph Node Mapping for Endometrial Cancer: Surgical Outcomes and Cost Analysis.

PubMed

Moukarzel, Lea A; Sinno, Abdulrahman K; Fader, Amanda N; Tanner, Edward J

To compare operative times, surgical outcomes, and costs of robotic laparoendoscopic single-site (R-LESS) vs multiport robotic (MPR) total laparoscopic hysterectomy (TLH) with sentinel lymph node (SLN) mapping for low-risk endometrial cancer. Retrospective cohort study (Canadian Task Force classification II-2). Academic university hospital. Patients with a biopsy-proven diagnosis of complex atypical hyperplasia (CAH) or low-grade (1 or 2) endometrial cancer with body mass index <30 kg/m 2 and undergoing robotic TLH and SLN mapping between 2012 and 2016 were included. Surgical outcomes and cost data were collected retrospectively and analyzed based on the surgical approach with R-LESS vs MPR assistance. Twenty-seven patients who met the inclusion criteria were identified, including 14 patients who underwent R-LESS TLH with SLN mapping and 13 patients who underwent MPR TLH with SLN mapping. Median uterine weight was comparable in the 2 cohorts (111.3 g vs 83.8 g; p = .33). Operative and console times were equivalent with the R-LESS and MPR approaches (median, 175 minutes vs 184 minutes, p = .61 and 136 vs 140 minutes, p = .12, respectively). Median estimated blood loss was 50 mL in both cohorts. Successful bilateral SLN mapping occurred in 85.7% of the R-LESS procedures and 76.9% of MPR procedures. No intraoperative or 30-day complications were encountered, and all patients were discharged within 23 hours of surgery. MPR was associated with additional disposable instrument and drape costs of $460 to $660 compared with R-LESS, depending on the surgeon's instrument selection. Average total hospital charges were lower for R-LESS procedures ($13,410 vs $15,952; p < .05). In highly selected patients with CAH or low-grade endometrial cancer undergoing TLH and SLN mapping, R-LESS appears to result in equivalent perioperative outcomes as a MPR approach while offering a more cost-effective option. Further research is needed to determine the benefits of R-LESS procedures in the gynecologic oncology setting. Copyright © 2017 AAGL. Published by Elsevier Inc. All rights reserved.

Isolation of Mycobacterium avium subsp paratuberculosis (Map) from feral cats on a dairy farm with Map-infected cattle.

PubMed

Palmer, Mitchell V; Stoffregen, William C; Carpenter, Jeremy G; Stabel, Judith R

2005-07-01

Paratuberculosis is an economically important disease of dairy cattle caused by Mycobacterium avium subsp. paratuberculosis (Map). The role of nonruminant, nondomestic animals in the epidemiology of paratuberculosis in cattle is unclear. To examine nonruminant, nondomestic animals for the presence of Map, 25 feral cats, nine mice (species unknown), eight rabbits (Sylvilagus floridanus), six raccoons (Procyon lotor), and three opossums (Didelphis virginiana) were collected from a mid-western dairy with known Map-infected cattle. Mycobacterium avium subsp. paratuberculosis was isolated from the mesenteric lymph node from seven of 25 (28%) feral cats. Ileum was culture-positive for three of these seven cats, and an isolation of Map was also made from the ileum of one of nine (11%) mice. Tissue samples from other species were negative as determined by Map culture; microscopic lesions consistent with paratuberculosis were not seen in any animal. Restriction fragment polymorphism analysis of isolates from cats and dairy cattle suggest interspecies transmission. The means by which interspecies transmission occurred may be through ingestion of Map-contaminated feces or waste milk or through ingestion of Map-infected prey. Shedding of Map from infected cats was not evaluated. The epidemiologic role of Map-infected feral cats on dairy farms requires further investigation.

Preclinical Potency and Biodistribution Studies of an AAV 5 Vector Expressing Human Interferon-β (ART-I02) for Local Treatment of Patients with Rheumatoid Arthritis

PubMed Central

Aalbers, Caroline J.; Bevaart, Lisette; Loiler, Scott; de Cortie, Karin; Wright, J. Fraser; Mingozzi, Federico; Tak, Paul P.; Vervoordeldonk, Margriet J.

2015-01-01

Introduction Proof of concept for local gene therapy for the treatment of arthritis with immunomodulatory cytokine interferon beta (IFN-β) has shown promising results in animal models of rheumatoid arthritis (RA). For the treatment of RA patients, we engineered a recombinant adeno-associated serotype 5 vector (rAAV5) encoding human (h)IFN-β under control of a nuclear factor κB promoter (ART-I02). Methods The potency of ART-I02 in vitro as well as biodistribution in vivo in arthritic animals was evaluated to characterize the vector prior to clinical application. ART-I02 expression and bioactivity after transduction was evaluated in fibroblast-like synoviocytes (FLS) from different species. Biodistribution of the vector after local injection was assessed in a rat adjuvant arthritis model through qPCR analysis of vector DNA. In vivo imaging was used to investigate transgene expression and kinetics in a mouse collagen induced arthritis model. Results Transduction of RA FLS in vitro with ART-I02 resulted in high expression levels of bioactive hIFN-β. Transduction of FLS from rhesus monkeys, rodents and rabbits with ART-I02 showed high transgene expression, and hIFN-β proved bioactive in FLS from rhesus monkeys. Transgene expression and bioactivity in RA FLS were unaltered in the presence of methotrexate. In vivo, vector biodistribution analysis in rats after intra-articular injection of ART-I02 demonstrated that the majority of vector DNA remained in the joint (>93%). In vivo imaging in mice confirmed local expression of rAAV5 in the knee joint region and demonstrated rapid detectable and sustained expression up until 7 weeks. Conclusions These data show that hIFN-β produced by RA FLS transduced with ART-I02 is bioactive and that intra-articular delivery of rAAV5 drives expression of a therapeutic transgene in the joint, with only limited biodistribution of vector DNA to other tissues, supporting progress towards a phase 1 clinical trial for the local treatment of arthritis in patients with RA. PMID:26107769

Preclinical Potency and Biodistribution Studies of an AAV 5 Vector Expressing Human Interferon-β (ART-I02) for Local Treatment of Patients with Rheumatoid Arthritis.

PubMed

Aalbers, Caroline J; Bevaart, Lisette; Loiler, Scott; de Cortie, Karin; Wright, J Fraser; Mingozzi, Federico; Tak, Paul P; Vervoordeldonk, Margriet J

2015-01-01

Proof of concept for local gene therapy for the treatment of arthritis with immunomodulatory cytokine interferon beta (IFN-β) has shown promising results in animal models of rheumatoid arthritis (RA). For the treatment of RA patients, we engineered a recombinant adeno-associated serotype 5 vector (rAAV5) encoding human (h)IFN-β under control of a nuclear factor κB promoter (ART-I02). The potency of ART-I02 in vitro as well as biodistribution in vivo in arthritic animals was evaluated to characterize the vector prior to clinical application. ART-I02 expression and bioactivity after transduction was evaluated in fibroblast-like synoviocytes (FLS) from different species. Biodistribution of the vector after local injection was assessed in a rat adjuvant arthritis model through qPCR analysis of vector DNA. In vivo imaging was used to investigate transgene expression and kinetics in a mouse collagen induced arthritis model. Transduction of RA FLS in vitro with ART-I02 resulted in high expression levels of bioactive hIFN-β. Transduction of FLS from rhesus monkeys, rodents and rabbits with ART-I02 showed high transgene expression, and hIFN-β proved bioactive in FLS from rhesus monkeys. Transgene expression and bioactivity in RA FLS were unaltered in the presence of methotrexate. In vivo, vector biodistribution analysis in rats after intra-articular injection of ART-I02 demonstrated that the majority of vector DNA remained in the joint (>93%). In vivo imaging in mice confirmed local expression of rAAV5 in the knee joint region and demonstrated rapid detectable and sustained expression up until 7 weeks. These data show that hIFN-β produced by RA FLS transduced with ART-I02 is bioactive and that intra-articular delivery of rAAV5 drives expression of a therapeutic transgene in the joint, with only limited biodistribution of vector DNA to other tissues, supporting progress towards a phase 1 clinical trial for the local treatment of arthritis in patients with RA.

Sentinel lymph node biopsy is indicated for patients with thick clinically lymph node-negative melanoma.

PubMed

Yamamoto, Maki; Fisher, Kate J; Wong, Joyce Y; Koscso, Jonathan M; Konstantinovic, Monique A; Govsyeyev, Nicholas; Messina, Jane L; Sarnaik, Amod A; Cruse, C Wayne; Gonzalez, Ricardo J; Sondak, Vernon K; Zager, Jonathan S

2015-05-15

Sentinel lymph node biopsy (SLNB) is indicated for the staging of clinically lymph node-negative melanoma of intermediate thickness, but its use is controversial in patients with thick melanoma. From 2002 to 2012, patients with melanoma measuring ≥4 mm in thickness were evaluated at a single institution. Associations between survival and clinicopathologic characteristics were explored. Of 571 patients with melanomas measuring ≥4 mm in thickness and no distant metastases, the median age was 66 years and 401 patients (70.2%) were male. The median Breslow thickness was 6.2 mm; the predominant subtype was nodular (45.4%). SLNB was performed in 412 patients (72%) whereas 46 patients (8.1%) presented with clinically lymph node-positive disease and 113 patients (20%) did not undergo SLNB. A positive SLN was found in 161 of 412 patients (39.1%). For SLNB performed at the study institution, 14 patients with a negative SLNB developed disease recurrence in the mapped lymph node basin (false-negative rate, 12.3%). The median disease-specific survival (DSS), overall survival (OS), and recurrence-free survival (RFS) for the entire cohort were 62.1 months, 42.5 months, and 21.2 months, respectively. The DSS and OS for patients with a negative SLNB were 82.4 months and 53.4 months, respectively; 41.2 months and 34.7 months, respectively, for patients with positive SLNB; and 26.8 months and 22 months, respectively, for patients with clinically lymph node-positive disease (P<.0001). The median RFS was 32.4 months for patients who were SLNB negative, 14.3 months for patients who were SLNB positive, and 6.8 months for patients with clinically lymph node-positive disease (P<.0001). With an acceptably low false-negative rate, patients with thick melanoma and a negative SLNB appear to have significantly prolonged RFS, DSS, and OS compared with those with a positive SLNB. Therefore, SLNB should be considered as indicated for patients with thick, clinically lymph node-negative melanoma. © 2015 American Cancer Society.

Estimation of paclitaxel biodistribution and uptake in human-derived xenografts in vivo with (18)F-fluoropaclitaxel.

PubMed

Gangloff, Anne; Hsueh, Wei-Ann; Kesner, Amanda L; Kiesewetter, Dale O; Pio, Betty S; Pegram, Mark D; Beryt, Malgorzata; Townsend, Allison; Czernin, Johannes; Phelps, Michael E; Silverman, Daniel H S

2005-11-01

Paclitaxel (PAC) is widely used as a chemotherapy drug in the treatment of various malignancies, including breast, ovarian, and lung cancers. We examined the biodistribution of (18)F-fluoropaclitaxel ((18)F-FPAC) in mice with and without human breast cancer tumor xenografts by use of small-animal-dedicated PET (microPET) and clinically practical semiquantitative methods. We compared the PET data to data derived from direct harvesting and analysis of blood, organs, and breast carcinoma xenografts. PET data were acquired after tail vein injection of (18)F-FPAC in nude mice. Tracer biodistribution in reconstructed images was quantified by region-of-interest analysis. Biodistribution also was assessed by harvesting and analysis of dissected organs, tumors, and blood after coadministration of (18)F-FPAC and (3)H-PAC. (18)F content in each tissue was assessed with a gamma-well counter, and (3)H content was quantified by scintillation counting of solubilized tissue after (18)F radioactive decay. The distributions of (18)F-FPAC and (3)H-PAC were very similar, with the highest concentrations in the small intestine, the lowest concentrations in the brain, and intermediate concentrations in tumor. Uptake in these and other tissues was not inhibited by the presence of more pharmacologic doses of unlabeled PAC. Administration of the P-glycoprotein modulator cyclosporine doubled the uptake of both (18)F-FPAC and (3)H-PAC into tumor. PET studies with (18)F-FPAC can be used in conjunction with clinically practical quantification methods to yield estimates of PAC uptake in breast cancer tumors and normal organs noninvasively.

Efficient characterization of phase space mapping in axially symmetric optical systems

NASA Astrophysics Data System (ADS)

Barbero, Sergio; Portilla, Javier

2018-01-01

Phase space mapping, typically between an object and image plane, characterizes an optical system within a geometrical optics framework. We propose a novel conceptual frame to characterize the phase mapping in axially symmetric optical systems for arbitrary object locations, not restricted to a specific object plane. The idea is based on decomposing the phase mapping into a set of bivariate equations corresponding to different values of the radial coordinate on a specific object surface (most likely the entrance pupil). These equations are then approximated through bivariate Chebyshev interpolation at Chebyshev nodes, which guarantees uniform convergence. Additionally, we propose the use of a new concept (effective object phase space), defined as the set of points of the phase space at the first optical element (typically the entrance pupil) that are effectively mapped onto the image surface. The effective object phase space provides, by means of an inclusion test, a way to avoid tracing rays that do not reach the image surface.

Symbiotic Navigation in Multi-Robot Systems with Remote Obstacle Knowledge Sharing

PubMed Central

Ravankar, Abhijeet; Ravankar, Ankit A.; Kobayashi, Yukinori; Emaru, Takanori

2017-01-01

Large scale operational areas often require multiple service robots for coverage and task parallelism. In such scenarios, each robot keeps its individual map of the environment and serves specific areas of the map at different times. We propose a knowledge sharing mechanism for multiple robots in which one robot can inform other robots about the changes in map, like path blockage, or new static obstacles, encountered at specific areas of the map. This symbiotic information sharing allows the robots to update remote areas of the map without having to explicitly navigate those areas, and plan efficient paths. A node representation of paths is presented for seamless sharing of blocked path information. The transience of obstacles is modeled to track obstacles which might have been removed. A lazy information update scheme is presented in which only relevant information affecting the current task is updated for efficiency. The advantages of the proposed method for path planning are discussed against traditional method with experimental results in both simulation and real environments. PMID:28678193

Mars Structural and Stratigraphic Mapping along the Coprates Rise

NASA Technical Reports Server (NTRS)

Saunders, R Stephen

2009-01-01

This geologic mapping project supports a topical study of structures in east Thaumasia associated with the Coprates rise. The study examines cuesta-like features on the east flank of the Coprates rise first identified by Saunders et al. [1]. Mapping combines detailed local stratigraphy, structural geology and topography. Hogbacks and cuestas indicate erosion of tilted rock units. The extent of the erosion will be determined in the course of the mapping. The region of interest lies along the eastern margin of Thaumasia bounded by latitudes -15 and -35 and longitudes 50 to 70 W (Figure 1). Three MTM geologic quadrangles are being compiled for publication by the USGS (-20057, -25057, -30057). All existing data sources are used including THEMIS, MOC, CTX, HiRISE, MOLA and gravity, as well as higher level data available through the PDS data nodes at ASU, UA and Washington University. The extremely valuable ASU JMARS tools are used for analysis of many of the data sets. ArcGIS software has been obtained and is being learned for the map compilation.

Assortative Mating: Encounter-Network Topology and the Evolution of Attractiveness

PubMed Central

Dipple, S.; Jia, T.; Caraco, T.; Korniss, G.; Szymanski, B. K.

2017-01-01

We model a social-encounter network where linked nodes match for reproduction in a manner depending probabilistically on each node’s attractiveness. The developed model reveals that increasing either the network’s mean degree or the “choosiness” exercised during pair formation increases the strength of positive assortative mating. That is, we note that attractiveness is correlated among mated nodes. Their total number also increases with mean degree and selectivity during pair formation. By iterating over the model’s mapping of parents onto offspring across generations, we study the evolution of attractiveness. Selection mediated by exclusion from reproduction increases mean attractiveness, but is rapidly balanced by skew in the offspring distribution of highly attractive mated pairs. PMID:28345625

Hydrophobic Effect from Conjugated Chemicals or Drugs on In Vivo Biodistribution of RNA Nanoparticles.

PubMed

Jasinski, Daniel L; Yin, Hongran; Li, Zhefeng; Guo, Peixuan

2018-01-01

Liver or other organ accumulation of drugs is one of the major problems that leads to toxicity and side effects in therapy using chemicals or other macromolecules. It has been shown that specially designed RNA nanoparticles can specifically target cancer cells, silence oncogenic genes, and stop cancer growth with little or no accumulation in the liver or other vital organs. It is well known that physical properties of nanoparticles such as size, shape, and surface chemistry affect biodistribution and pharmacokinetic profiles in vivo. This study examined how the hydrophobicity of chemicals conjugated to RNA nanoparticles affect in vivo biodistribution. Weaker organ accumulation was observed for hydrophobic chemicals after they were conjugated to RNA nanoparticles, revealing RNA's ability to solubilize hydrophobic chemicals. It was found that different chemicals conjugated to RNA nanoparticles resulted in the alteration of RNA hydrophobicity. Stronger hydrophobicity induced by chemical conjugates resulted in higher accumulation of RNA nanoparticles in vital organs in mice. This study provides new insights for handling drug insolubility, therapeutic toxicity, and organ clearance in drug development.

Comparing in vivo biodistribution with radiolabeling and Franz cell permeation assay to validate the efficacy of both methodologies in the evaluation of nanoemulsions: a safety approach

NASA Astrophysics Data System (ADS)

Cerqueira-Coutinho, C. S.; De Campo, V. E. B.; Rossi, A. L.; Veiga, V. F.; Holandino, C.; Freitas, Z. M. F.; Ricci-Junior, E.; Mansur, C. R. E.; Santos, E. P.; Santos-Oliveira, R.

2016-01-01

The Franz cells permeation assay has been performed for over 25 years. However, the advent of nanotechnology created a whole new world, especially with regard to topical products. In this new global scenario an increasing number of nanostructure-based delivery systems (NDSs) have emerged and a global warning relating to the safety of these NDSs is arising. This work studied the efficacy of the Franz cells assay, comparing it with the radiolabeling biodistribution test. For this purpose a formulation of sunscreen based on an NDS was developed and characterized. The results demonstrated both that the NDS did not present in vitro cytotoxicity and that the radiolabeling biodistribution test is more precise for the evaluation of NDS cosmetics than the Franz cells assay, since it detected the permeation of the NDS at a picogram order. Due to this fact, and considering all the concerns related to NDSs and nanoparticles in general, more precise methods must be used in order to guarantee the safe use of these new classes of products.

Mammary lymphoscintigraphy with various radiopharmaceuticals in breast cancer.

PubMed

Imoto, S; Murakami, K; Ikeda, H; Fukukita, H; Moriyama, N

1999-10-01

Sentinel node biopsy (SNB) in breast cancer is a promising surgical technique that avoids unnecessary axillary lymph node dissection. To optimize lymphatic mapping with radiopharmaceuticals, mammary lymphoscintigraphy with 30-50 MBq of technetium-99m-diethylenetriamine pentaacetic acid human serum albumin (99mTc-HSAD), technetium-99m-human serum albumin (99mTc-HSA), or technetium-99m-tin colloid (99mTc-TC) were investigated in 69 cases of primary breast cancer. Dynamic early images were obtained during the first 30 or 40 minutes, and static delayed images were obtained 6 hours after tracer injection. Hot spots as sentinel lymph nodes (SLNs) appeared in 51 of 69 cases (74%): in early images in 27 cases and in delayed images in 24 cases. SLNs were visualized more frequently in 23 of the 26 cases (88%) treated with 99mTc-HSAD and in 21 of the 24 cases (88%) treated with 99mTc-HSA than in only 7 of the 19 cases (37%) treated with 99mTc-TC. In 26 of the 51 cases, SLNs were identified as faint spots in delayed images. There was a significant difference in the first appearance of SLNs on the lymphoscintiscan between 43 cases of dense breast parenchyma and 26 cases of fatty breast parenchyma. These results suggest that 99mTc-HSAD or 99mTc-HSA is acceptable for lymphatic mapping, but in cases which have faint spots in delayed images or fatty breast parenchyma, gamma probe-guided SNB may result in failure or misleading false-negative SLNs.

Topology reduction in deep convolutional feature extraction networks

NASA Astrophysics Data System (ADS)

Wiatowski, Thomas; Grohs, Philipp; Bölcskei, Helmut

2017-08-01

Deep convolutional neural networks (CNNs) used in practice employ potentially hundreds of layers and 10,000s of nodes. Such network sizes entail significant computational complexity due to the large number of convolutions that need to be carried out; in addition, a large number of parameters needs to be learned and stored. Very deep and wide CNNs may therefore not be well suited to applications operating under severe resource constraints as is the case, e.g., in low-power embedded and mobile platforms. This paper aims at understanding the impact of CNN topology, specifically depth and width, on the network's feature extraction capabilities. We address this question for the class of scattering networks that employ either Weyl-Heisenberg filters or wavelets, the modulus non-linearity, and no pooling. The exponential feature map energy decay results in Wiatowski et al., 2017, are generalized to O(a-N), where an arbitrary decay factor a > 1 can be realized through suitable choice of the Weyl-Heisenberg prototype function or the mother wavelet. We then show how networks of fixed (possibly small) depth N can be designed to guarantee that ((1 - ɛ) · 100)% of the input signal's energy are contained in the feature vector. Based on the notion of operationally significant nodes, we characterize, partly rigorously and partly heuristically, the topology-reducing effects of (effectively) band-limited input signals, band-limited filters, and feature map symmetries. Finally, for networks based on Weyl-Heisenberg filters, we determine the prototype function bandwidth that minimizes - for fixed network depth N - the average number of operationally significant nodes per layer.

Visibility graphs and symbolic dynamics

NASA Astrophysics Data System (ADS)

Lacasa, Lucas; Just, Wolfram

2018-07-01

Visibility algorithms are a family of geometric and ordering criteria by which a real-valued time series of N data is mapped into a graph of N nodes. This graph has been shown to often inherit in its topology nontrivial properties of the series structure, and can thus be seen as a combinatorial representation of a dynamical system. Here we explore in some detail the relation between visibility graphs and symbolic dynamics. To do that, we consider the degree sequence of horizontal visibility graphs generated by the one-parameter logistic map, for a range of values of the parameter for which the map shows chaotic behaviour. Numerically, we observe that in the chaotic region the block entropies of these sequences systematically converge to the Lyapunov exponent of the time series. Hence, Pesin's identity suggests that these block entropies are converging to the Kolmogorov-Sinai entropy of the physical measure, which ultimately suggests that the algorithm is implicitly and adaptively constructing phase space partitions which might have the generating property. To give analytical insight, we explore the relation k(x) , x ∈ [ 0 , 1 ] that, for a given datum with value x, assigns in graph space a node with degree k. In the case of the out-degree sequence, such relation is indeed a piece-wise constant function. By making use of explicit methods and tools from symbolic dynamics we are able to analytically show that the algorithm indeed performs an effective partition of the phase space and that such partition is naturally expressed as a countable union of subintervals, where the endpoints of each subinterval are related to the fixed point structure of the iterates of the map and the subinterval enumeration is associated with particular ordering structures that we called motifs.

An algorithm for automated layout of process description maps drawn in SBGN.

PubMed

Genc, Begum; Dogrusoz, Ugur

2016-01-01

Evolving technology has increased the focus on genomics. The combination of today's advanced techniques with decades of molecular biology research has yielded huge amounts of pathway data. A standard, named the Systems Biology Graphical Notation (SBGN), was recently introduced to allow scientists to represent biological pathways in an unambiguous, easy-to-understand and efficient manner. Although there are a number of automated layout algorithms for various types of biological networks, currently none specialize on process description (PD) maps as defined by SBGN. We propose a new automated layout algorithm for PD maps drawn in SBGN. Our algorithm is based on a force-directed automated layout algorithm called Compound Spring Embedder (CoSE). On top of the existing force scheme, additional heuristics employing new types of forces and movement rules are defined to address SBGN-specific rules. Our algorithm is the only automatic layout algorithm that properly addresses all SBGN rules for drawing PD maps, including placement of substrates and products of process nodes on opposite sides, compact tiling of members of molecular complexes and extensively making use of nested structures (compound nodes) to properly draw cellular locations and molecular complex structures. As demonstrated experimentally, the algorithm results in significant improvements over use of a generic layout algorithm such as CoSE in addressing SBGN rules on top of commonly accepted graph drawing criteria. An implementation of our algorithm in Java is available within ChiLay library (https://github.com/iVis-at-Bilkent/chilay). ugur@cs.bilkent.edu.tr or dogrusoz@cbio.mskcc.org Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press.

An algorithm for automated layout of process description maps drawn in SBGN

PubMed Central

Genc, Begum; Dogrusoz, Ugur

2016-01-01

Motivation: Evolving technology has increased the focus on genomics. The combination of today’s advanced techniques with decades of molecular biology research has yielded huge amounts of pathway data. A standard, named the Systems Biology Graphical Notation (SBGN), was recently introduced to allow scientists to represent biological pathways in an unambiguous, easy-to-understand and efficient manner. Although there are a number of automated layout algorithms for various types of biological networks, currently none specialize on process description (PD) maps as defined by SBGN. Results: We propose a new automated layout algorithm for PD maps drawn in SBGN. Our algorithm is based on a force-directed automated layout algorithm called Compound Spring Embedder (CoSE). On top of the existing force scheme, additional heuristics employing new types of forces and movement rules are defined to address SBGN-specific rules. Our algorithm is the only automatic layout algorithm that properly addresses all SBGN rules for drawing PD maps, including placement of substrates and products of process nodes on opposite sides, compact tiling of members of molecular complexes and extensively making use of nested structures (compound nodes) to properly draw cellular locations and molecular complex structures. As demonstrated experimentally, the algorithm results in significant improvements over use of a generic layout algorithm such as CoSE in addressing SBGN rules on top of commonly accepted graph drawing criteria. Availability and implementation: An implementation of our algorithm in Java is available within ChiLay library (https://github.com/iVis-at-Bilkent/chilay). Contact: ugur@cs.bilkent.edu.tr or dogrusoz@cbio.mskcc.org Supplementary information: Supplementary data are available at Bioinformatics online. PMID:26363029

Efficacy and adequacy of conventional transbronchial needle aspiration of IASLC stations 4R, 4L and 7 using endobronchial landmarks provided by the Wang nodal mapping system in the staging of lung cancer.

PubMed

Liu, Qinghua; Han, Songyan; Arias, Sixto; Turner, J Francis; Lee, Hans; Browning, Robert; Wang, Ko-Pen

2016-01-01

The role of transbronchial needle aspiration (TBNA) in the diagnosis and staging of lung cancer has been well established. Recently, the efficacy of conventional TBNA in the staging of lung cancer has been enhanced by the use of endobronchial ultrasound (EBUS)-TBNA. Our study sought to evaluate the adequacy of TBNA of International Association for the Study of Lung Cancer (IASLC) stations 4R, 4L and 7 using endobronchial landmarks provided by the Wang nodal mapping system in the staging of lung cancer. We retrospectively analyzed all bronchoscopic cases with conventional TBNA punctures positive for malignancy at our institution from 1 January to 31 October 2014. The endobronchial puncture site was guided by the Wang nodal mapping system. The Wang stations were correlated with the IASLC lymph node map. No endobronchial ultrasound or rapid on-site evaluation was used. Pathological analysis included cytological and histological examination. Diagnosis by histological analysis was obtained in 115 (55.3%) out of 208 puncture sites. The metastatic lymph nodes were distributed at IASLC stations 4R (W1, 3, 5) 46.6 %, 7 (W2, 8, 10) 19.7%, 4L (W4, 6) 11.5%, 11R (W7, W9) 11.1% 11L (W11) 9.6%, 2R (high station W3) 0.5%, and the proximal portion of station 8 (station W10 beyond the middle lobe orifice) 1%. No complications were observed. IASLC station 4R (W1, 3, 5), 7 (W2, 8, 10) and 4L (W4, 6) are adequate for the staging of lung cancer.

Melanin nanoparticles derived from a homology of medicine and food for sentinel lymph node mapping and photothermal in vivo cancer therapy.

PubMed

Chu, Maoquan; Hai, Wangxi; Zhang, Zheyu; Wo, Fangjie; Wu, Qiang; Zhang, Zefei; Shao, Yuxiang; Zhang, Ding; Jin, Lu; Shi, Donglu

2016-06-01

The use of non-toxic or low toxicity materials exhibiting dual functionality for use in sentinel lymph node (SLN) mapping and cancer therapy has attracted considerable attention during the past two decades. Herein, we report that the natural black sesame melanin (BSM) extracted from black sesame seeds (Sesamum indicum L.) shows exciting potential for SLN mapping and cancer photothermal therapy. Aqueous solutions of BSM under neutral and alkaline conditions can assemble into sheet-like nanoparticles ranging from 20 to 200 nm in size. The BSM nanoparticles were encapsulated by liposomes to improve their water solubility and the encapsulated and bare BSM nanoparticles were both non-toxic to cells. Furthermore, the liposome-encapsulated BSM nanoparticles (liposome-BSM) did not exhibit any long-term toxicity in mice. The liposome-BSM nanoparticles were subsequently used to passively target healthy and tumor-bearing mice SLNs, which were identified by the black color of the nanoparticles. BSM also strongly absorbed light in the near-infrared (NIR) range, which was rapidly converted to heat energy. Human esophagus carcinoma cells (Eca-109) were killed efficiently by liposome-BSM nanocomposites upon NIR laser irradiation. Furthermore, mouse tumor tissues grown from Eca-109 cells were seriously damaged by the photothermal effects of the liposome-BSM nanocomposites, with significant tumor growth suppression compared with controls. Given that BSM is a safe and nutritious biomaterial that can be easily obtained from black sesame seed, the results presented herein represent an important development in the use of natural biomaterials for clinical SLN mapping and cancer therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

A handheld SPIO-based sentinel lymph node mapping device using differential magnetometry

NASA Astrophysics Data System (ADS)

Waanders, S.; Visscher, M.; Wildeboer, R. R.; Oderkerk, T. O. B.; Krooshoop, H. J. G.; ten Haken, B.

2016-11-01

Sentinel lymph node biopsy has become a staple tool in the diagnosis of breast cancer. By replacing the morbidity-plagued axillary node clearance with removing only those nodes most likely to contain metastases, it has greatly improved the quality of life of many breast cancer patients. However, due to the use of ionizing radiation emitted by the technetium-based tracer material, the current sentinel lymph node biopsy has serious drawbacks. Most urgently, the reliance on radioisotopes limits the application of this procedure to small parts of the developed world, and it imposes restrictions on patient planning and hospital logistics. Magnetic alternatives have been tested in recent years, but all have their own drawbacks, mostly related to interference from metallic instruments and electromagnetic noise coming from the human body. In this paper, we demonstrate an alternative approach that utilizes the unique nonlinear magnetic properties of superparamagnetic iron oxide nanoparticles to eliminate the drawbacks of both the traditional gamma-radiation centered approach and the novel magnetic techniques pioneered by others. Contrary to many other nonlinear magnetic approaches however, field amplitudes are limited to 5 mT, which enables handheld operation without additional cooling. We show that excellent mass sensitivity can be obtained without the need for external re-balancing of the probe to negate any influences from the human body. Additionally, we show how this approach can be used to suppress artefacts resulting from the presence of metallic instruments, which are a significant dealbreaker when using conventional magnetometry-based approaches.

Failure detection in high-performance clusters and computers using chaotic map computations

DOEpatents

Rao, Nageswara S.

2015-09-01

A programmable media includes a processing unit capable of independent operation in a machine that is capable of executing 10.sup.18 floating point operations per second. The processing unit is in communication with a memory element and an interconnect that couples computing nodes. The programmable media includes a logical unit configured to execute arithmetic functions, comparative functions, and/or logical functions. The processing unit is configured to detect computing component failures, memory element failures and/or interconnect failures by executing programming threads that generate one or more chaotic map trajectories. The central processing unit or graphical processing unit is configured to detect a computing component failure, memory element failure and/or an interconnect failure through an automated comparison of signal trajectories generated by the chaotic maps.

Genes and QTLs controlling inflorescence and stem branch architecture in Leymus (Poaceae: Triticeae) Wildrye.

PubMed

Larson, Steven R; Kellogg, Elizabeth A; Jensen, Kevin B

2013-01-01

Grass inflorescence and stem branches show recognizable architectural differences among species. The inflorescence branches of Triticeae cereals and grasses, including wheat, barley, and 400-500 wild species, are usually contracted into a spike formation, with the number of flowering branches (spikelets) per node conserved within species and genera. Perennial Triticeae grasses of genus Leymus are unusual in that the number of spikelets per node varies, inflorescences may have panicle branches, and vegetative stems may form subterranean rhizomes. Leymus cinereus and L. triticoides show discrete differences in inflorescence length, branching architecture, node number, and density; number of spikelets per node and florets per spikelet; culm length and width; and perimeter of rhizomatous spreading. Quantitative trait loci controlling these traits were detected in 2 pseudo-backcross populations derived from the interspecific hybrids using a linkage map with 360 expressed gene sequence markers from Leymus tiller and rhizome branch meristems. Alignments of genes, mutations, and quantitative trait loci controlling similar traits in other grass species were identified using the Brachypodium genome reference sequence. Evidence suggests that loci controlling inflorescence and stem branch architecture in Leymus are conserved among the grasses, are governed by natural selection, and can serve as possible gene targets for improving seed, forage, and grain production.

Morpho-functional characterization of the systemic venous pole of the reptile heart.

PubMed

Jensen, Bjarke; Vesterskov, Signe; Boukens, Bastiaan J; Nielsen, Jan M; Moorman, Antoon F M; Christoffels, Vincent M; Wang, Tobias

2017-07-27

Mammals evolved from reptile-like ancestors, and while the mammalian heart is driven by a distinct sinus node, a sinus node is not apparent in reptiles. We characterized the myocardial systemic venous pole, the sinus venosus, in reptiles to identify the dominant pacemaker and to assess whether the sinus venosus remodels and adopts an atrium-like phenotype as observed in mammals. Anolis lizards had an extensive sinus venosus of myocardium expressing Tbx18. A small sub-population of cells encircling the sinuatrial junction expressed Isl1, Bmp2, Tbx3, and Hcn4, homologues of genes marking the mammalian sinus node. Electrical mapping showed that hearts of Anolis lizards and Python snakes were driven from the sinuatrial junction. The electrical impulse was delayed between the sinus venosus and the right atrium, allowing the sinus venosus to contract and aid right atrial filling. In proximity of the systemic veins, the Anolis sinus venosus expressed markers of the atrial phenotype Nkx2-5 and Gja5. In conclusion, the reptile heart is driven by a pacemaker region with an expression signature similar to that of the immature sinus node of mammals. Unlike mammals, reptiles maintain a sinuatrial delay of the impulse, allowing the partly atrialized sinus venosus to function as a chamber.

Influence maximization in complex networks through optimal percolation

NASA Astrophysics Data System (ADS)

Morone, Flaviano; Makse, Hernán A.

2015-08-01

The whole frame of interconnections in complex networks hinges on a specific set of structural nodes, much smaller than the total size, which, if activated, would cause the spread of information to the whole network, or, if immunized, would prevent the diffusion of a large scale epidemic. Localizing this optimal, that is, minimal, set of structural nodes, called influencers, is one of the most important problems in network science. Despite the vast use of heuristic strategies to identify influential spreaders, the problem remains unsolved. Here we map the problem onto optimal percolation in random networks to identify the minimal set of influencers, which arises by minimizing the energy of a many-body system, where the form of the interactions is fixed by the non-backtracking matrix of the network. Big data analyses reveal that the set of optimal influencers is much smaller than the one predicted by previous heuristic centralities. Remarkably, a large number of previously neglected weakly connected nodes emerges among the optimal influencers. These are topologically tagged as low-degree nodes surrounded by hierarchical coronas of hubs, and are uncovered only through the optimal collective interplay of all the influencers in the network. The present theoretical framework may hold a larger degree of universality, being applicable to other hard optimization problems exhibiting a continuous transition from a known phase.

An artificial immune system approach with secondary response for misbehavior detection in mobile ad hoc networks.

PubMed

Sarafijanović, Slavisa; Le Boudec, Jean-Yves

2005-09-01

In mobile ad hoc networks, nodes act both as terminals and information relays, and they participate in a common routing protocol, such as dynamic source routing (DSR). The network is vulnerable to routing misbehavior, due to faulty or malicious nodes. Misbehavior detection systems aim at removing this vulnerability. In this paper, we investigate the use of an artificial immune system (AIS) to detect node misbehavior in a mobile ad hoc network using DSR. The system is inspired by the natural immune system (IS) of vertebrates. Our goal is to build a system that, like its natural counterpart, automatically learns, and detects new misbehavior. We describe our solution for the classification task of the AIS; it employs negative selection and clonal selection, the algorithms for learning and adaptation used by the natural IS. We define how we map the natural IS concepts such as self, antigen, and antibody to a mobile ad hoc network and give the resulting algorithm for classifying nodes as misbehaving. We implemented the system in the network simulator Glomosim; we present detection results and discuss how the system parameters affect the performance of primary and secondary response. Further steps will extend the design by using an analogy to the innate system, danger signal, and memory cells.

Influence maximization in complex networks through optimal percolation.

PubMed

Morone, Flaviano; Makse, Hernán A

2015-08-06

The whole frame of interconnections in complex networks hinges on a specific set of structural nodes, much smaller than the total size, which, if activated, would cause the spread of information to the whole network, or, if immunized, would prevent the diffusion of a large scale epidemic. Localizing this optimal, that is, minimal, set of structural nodes, called influencers, is one of the most important problems in network science. Despite the vast use of heuristic strategies to identify influential spreaders, the problem remains unsolved. Here we map the problem onto optimal percolation in random networks to identify the minimal set of influencers, which arises by minimizing the energy of a many-body system, where the form of the interactions is fixed by the non-backtracking matrix of the network. Big data analyses reveal that the set of optimal influencers is much smaller than the one predicted by previous heuristic centralities. Remarkably, a large number of previously neglected weakly connected nodes emerges among the optimal influencers. These are topologically tagged as low-degree nodes surrounded by hierarchical coronas of hubs, and are uncovered only through the optimal collective interplay of all the influencers in the network. The present theoretical framework may hold a larger degree of universality, being applicable to other hard optimization problems exhibiting a continuous transition from a known phase.

An improved spatial contour tree constructed method

NASA Astrophysics Data System (ADS)

Zheng, Yi; Zhang, Ling; Guilbert, Eric; Long, Yi

2018-05-01

Contours are important data to delineate the landform on a map. A contour tree provides an object-oriented description of landforms and can be used to enrich the topological information. The traditional contour tree is used to store topological relationships between contours in a hierarchical structure and allows for the identification of eminences and depressions as sets of nested contours. This research proposes an improved contour tree so-called spatial contour tree that contains not only the topological but also the geometric information. It can be regarded as a terrain skeleton in 3-dimention, and it is established based on the spatial nodes of contours which have the latitude, longitude and elevation information. The spatial contour tree is built by connecting spatial nodes from low to high elevation for a positive landform, and from high to low elevation for a negative landform to form a hierarchical structure. The connection between two spatial nodes can provide the real distance and direction as a Euclidean vector in 3-dimention. In this paper, the construction method is tested in the experiment, and the results are discussed. The proposed hierarchical structure is in 3-demintion and can show the skeleton inside a terrain. The structure, where all nodes have geo-information, can be used to distinguish different landforms and applied for contour generalization with consideration of geographic characteristics.

Boron biodistribution for BNCT in the hamster cheek pouch oral cancer model: Combined administration of BSH and BPA

DOE Office of Scientific and Technical Information (OSTI.GOV)

D.W. Nigg; William Bauer; Various Others

Sodium mercaptoundecahydro-closo-dodecaborate (BSH) is being investigated clinically for BNCT. We examined the biodistribution of BSH and BPA administered jointly in different proportions in the hamster cheek pouch oral cancer model. The 3 assayed protocols were non-toxic, and showed preferential tumor boron uptake versus precancerous and normal tissue and therapeutic tumor boron concentration values (70–85 ppm). All 3 protocols warrant assessment in BNCT studies to contribute to the knowledge of (BSH+BPA)-BNCT radiobiology for head and neck cancer and optimize therapeutic efficacy.

Preclinical acute toxicity, biodistribution, pharmacokinetics, radiation dosimetry and microPET imaging studies of [(18)F]fluorocholine in mice.

PubMed

Silveira, Marina B; Ferreira, Soraya M Z M D; Nascimento, Leonardo T C; Costa, Flávia M; Mendes, Bruno M; Ferreira, Andrea V; Malamut, Carlos; Silva, Juliana B; Mamede, Marcelo

2016-10-01

[(18)F]Fluorocholine ([(18)F]FCH) has been proven to be effective in prostate cancer. Since [(18)F]FCH is classified as a new radiopharmaceutical in Brazil, preclinical safety and efficacy data are required to support clinical trials and to obtain its approval. The aim of this work was to perform acute toxicity, biodistribution, pharmacokinetics, radiation dosimetry and microPET imaging studies of [(18)F]FCH. The results could support its use in nuclear medicine as an important piece of work for regulatory in Brazil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Platelet kinetics and biodistribution in canine endotoxemia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sostman, H.D.; Zoghbi, S.S.; Smith, G.J.

Kinetics and magnitudes of changes in indium-labeled platelet biodistribution were studied in dogs given E. coli endotoxin. Marked, reversible, dose-dependent shifts of platelets from blood to lung and apparently irreversible shifts to liver were demonstrated. These were contemporaneous with alterations in blood gases and in pulmonary and systemic hemodynamics. Morphologic studies revealed atelectasis, sequestration of leukocytes and platelets in the lungs, and mild interstitial pulmonary edema. This study provides in vivo quantification of labeled platelet response to a specific stimulus, and illustrates a method that could be applied to more extensive study of blood element participation in acute lung injury.

Antifungal Therapy for Systemic Mycosis and the Nanobiotechnology Era: Improving Efficacy, Biodistribution and Toxicity.

PubMed

Souza, Ana C O; Amaral, Andre C

2017-01-01

Fungal diseases have been emerging as an important public health problem worldwide with the increase in host predisposition factors due to immunological dysregulations, immunosuppressive and/or anticancer therapy. Antifungal therapy for systemic mycosis is limited, most of times expensive and causes important toxic effects. Nanotechnology has become an interesting strategy to improve efficacy of traditional antifungal drugs, which allows lower toxicity, better biodistribution, and drug targeting, with promising results in vitro and in vivo . In this review, we provide a discussion about conventional antifungal and nanoantifungal therapies for systemic mycosis.

Los Alamos Programming Models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bergen, Benjamin Karl

This is the PDF of a powerpoint presentation from a teleconference on Los Alamos programming models. It starts by listing their assumptions for the programming models and then details a hierarchical programming model at the System Level and Node Level. Then it details how to map this to their internal nomenclature. Finally, a list is given of what they are currently doing in this regard.

Fast computation of voxel-level brain connectivity maps from resting-state functional MRI using l₁-norm as approximation of Pearson's temporal correlation: proof-of-concept and example vector hardware implementation.

PubMed

Minati, Ludovico; Zacà, Domenico; D'Incerti, Ludovico; Jovicich, Jorge

2014-09-01

An outstanding issue in graph-based analysis of resting-state functional MRI is choice of network nodes. Individual consideration of entire brain voxels may represent a less biased approach than parcellating the cortex according to pre-determined atlases, but entails establishing connectedness for 1(9)-1(11) links, with often prohibitive computational cost. Using a representative Human Connectome Project dataset, we show that, following appropriate time-series normalization, it may be possible to accelerate connectivity determination replacing Pearson correlation with l1-norm. Even though the adjacency matrices derived from correlation coefficients and l1-norms are not identical, their similarity is high. Further, we describe and provide in full an example vector hardware implementation of l1-norm on an array of 4096 zero instruction-set processors. Calculation times <1000 s are attainable, removing the major deterrent to voxel-based resting-sate network mapping and revealing fine-grained node degree heterogeneity. L1-norm should be given consideration as a substitute for correlation in very high-density resting-state functional connectivity analyses. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

Decision-Tree Formulation With Order-1 Lateral Execution

NASA Technical Reports Server (NTRS)

James, Mark

2007-01-01

A compact symbolic formulation enables mapping of an arbitrarily complex decision tree of a certain type into a highly computationally efficient multidimensional software object. The type of decision trees to which this formulation applies is that known in the art as the Boolean class of balanced decision trees. Parallel lateral slices of an object created by means of this formulation can be executed in constant time considerably less time than would otherwise be required. Decision trees of various forms are incorporated into almost all large software systems. A decision tree is a way of hierarchically solving a problem, proceeding through a set of true/false responses to a conclusion. By definition, a decision tree has a tree-like structure, wherein each internal node denotes a test on an attribute, each branch from an internal node represents an outcome of a test, and leaf nodes represent classes or class distributions that, in turn represent possible conclusions. The drawback of decision trees is that execution of them can be computationally expensive (and, hence, time-consuming) because each non-leaf node must be examined to determine whether to progress deeper into a tree structure or to examine an alternative. The present formulation was conceived as an efficient means of representing a decision tree and executing it in as little time as possible. The formulation involves the use of a set of symbolic algorithms to transform a decision tree into a multi-dimensional object, the rank of which equals the number of lateral non-leaf nodes. The tree can then be executed in constant time by means of an order-one table lookup. The sequence of operations performed by the algorithms is summarized as follows: 1. Determination of whether the tree under consideration can be encoded by means of this formulation. 2. Extraction of decision variables. 3. Symbolic optimization of the decision tree to minimize its form. 4. Expansion and transformation of all nested conjunctive-disjunctive paths to a flattened conjunctive form composed only of equality checks when possible. If each reduced conjunctive form contains only equality checks and all of these forms use the same variables, then the decision tree can be reduced to an order-one operation through a table lookup. The speedup to order one is accomplished by distributing each decision variable over a surface of a multidimensional object by mapping the equality constant to an index

a Public Platform for Geospatial Data Sharing for Disaster Risk Management

NASA Astrophysics Data System (ADS)

Balbo, S.; Boccardo, P.; Dalmasso, S.; Pasquali, P.

2013-01-01

Several studies have been conducted in Africa to assist local governments in addressing the risk situation related to natural hazards. Geospatial data containing information on vulnerability, impacts, climate change, disaster risk reduction is usually part of the output of such studies and is valuable to national and international organizations to reduce the risks and mitigate the impacts of disasters. Nevertheless this data isn't efficiently widely distributed and often resides in remote storage solutions hardly reachable. Spatial Data Infrastructures are technical solutions capable to solve this issue, by storing geospatial data and making them widely available through the internet. Among these solutions, GeoNode, an open source online platform for geospatial data sharing, has been developed in recent years. GeoNode is a platform for the management and publication of geospatial data. It brings together mature and stable open-source software projects under a consistent and easy-to-use interface allowing users, with little training, to quickly and easily share data and create interactive maps. GeoNode data management tools allow for integrated creation of data, metadata, and map visualizations. Each dataset in the system can be shared publicly or restricted to allow access to only specific users. Social features like user profiles and commenting and rating systems allow for the development of communities around each platform to facilitate the use, management, and quality control of the data the GeoNode instance contains (http://geonode.org/). This paper presents a case study scenario of setting up a Web platform based on GeoNode. It is a public platform called MASDAP and promoted by the Government of Malawi in order to support development of the country and build resilience against natural disasters. A substantial amount of geospatial data has already been collected about hydrogeological risk, as well as several other-disasters related information. Moreover this platform will help to ensure that the data created by a number of past or ongoing projects is maintained and that this information remains accessible and useful. An Integrated Flood Risk Management Plan for a river basin has already been included in the platform and other data from future disaster risk management projects will be added as well.

A scalable neuroinformatics data flow for electrophysiological signals using MapReduce.

PubMed

Jayapandian, Catherine; Wei, Annan; Ramesh, Priya; Zonjy, Bilal; Lhatoo, Samden D; Loparo, Kenneth; Zhang, Guo-Qiang; Sahoo, Satya S

2015-01-01

Data-driven neuroscience research is providing new insights in progression of neurological disorders and supporting the development of improved treatment approaches. However, the volume, velocity, and variety of neuroscience data generated from sophisticated recording instruments and acquisition methods have exacerbated the limited scalability of existing neuroinformatics tools. This makes it difficult for neuroscience researchers to effectively leverage the growing multi-modal neuroscience data to advance research in serious neurological disorders, such as epilepsy. We describe the development of the Cloudwave data flow that uses new data partitioning techniques to store and analyze electrophysiological signal in distributed computing infrastructure. The Cloudwave data flow uses MapReduce parallel programming algorithm to implement an integrated signal data processing pipeline that scales with large volume of data generated at high velocity. Using an epilepsy domain ontology together with an epilepsy focused extensible data representation format called Cloudwave Signal Format (CSF), the data flow addresses the challenge of data heterogeneity and is interoperable with existing neuroinformatics data representation formats, such as HDF5. The scalability of the Cloudwave data flow is evaluated using a 30-node cluster installed with the open source Hadoop software stack. The results demonstrate that the Cloudwave data flow can process increasing volume of signal data by leveraging Hadoop Data Nodes to reduce the total data processing time. The Cloudwave data flow is a template for developing highly scalable neuroscience data processing pipelines using MapReduce algorithms to support a variety of user applications.

A scalable neuroinformatics data flow for electrophysiological signals using MapReduce

PubMed Central

Jayapandian, Catherine; Wei, Annan; Ramesh, Priya; Zonjy, Bilal; Lhatoo, Samden D.; Loparo, Kenneth; Zhang, Guo-Qiang; Sahoo, Satya S.

2015-01-01

Data-driven neuroscience research is providing new insights in progression of neurological disorders and supporting the development of improved treatment approaches. However, the volume, velocity, and variety of neuroscience data generated from sophisticated recording instruments and acquisition methods have exacerbated the limited scalability of existing neuroinformatics tools. This makes it difficult for neuroscience researchers to effectively leverage the growing multi-modal neuroscience data to advance research in serious neurological disorders, such as epilepsy. We describe the development of the Cloudwave data flow that uses new data partitioning techniques to store and analyze electrophysiological signal in distributed computing infrastructure. The Cloudwave data flow uses MapReduce parallel programming algorithm to implement an integrated signal data processing pipeline that scales with large volume of data generated at high velocity. Using an epilepsy domain ontology together with an epilepsy focused extensible data representation format called Cloudwave Signal Format (CSF), the data flow addresses the challenge of data heterogeneity and is interoperable with existing neuroinformatics data representation formats, such as HDF5. The scalability of the Cloudwave data flow is evaluated using a 30-node cluster installed with the open source Hadoop software stack. The results demonstrate that the Cloudwave data flow can process increasing volume of signal data by leveraging Hadoop Data Nodes to reduce the total data processing time. The Cloudwave data flow is a template for developing highly scalable neuroscience data processing pipelines using MapReduce algorithms to support a variety of user applications. PMID:25852536

A Finite Element Method to Correct Deformable Image Registration Errors in Low-Contrast Regions

PubMed Central

Zhong, Hualiang; Kim, Jinkoo; Li, Haisen; Nurushev, Teamour; Movsas, Benjamin; Chetty, Indrin J.

2012-01-01

Image-guided adaptive radiotherapy requires deformable image registration to map radiation dose back and forth between images. The purpose of this study is to develop a novel method to improve the accuracy of an intensity-based image registration algorithm in low-contrast regions. A computational framework has been developed in this study to improve the quality of the “demons” registration. For each voxel in the registration’s target image, the standard deviation of image intensity in a neighborhood of this voxel was calculated. A mask for high-contrast regions was generated based on their standard deviations. In the masked regions, a tetrahedral mesh was refined recursively so that a sufficient number of tetrahedral nodes in these regions can be selected as driving nodes. An elastic system driven by the displacements of the selected nodes was formulated using a finite element method (FEM) and implemented on the refined mesh. The displacements of these driving nodes were generated with the “demons” algorithm. The solution of the system was derived using a conjugated gradient method, and interpolated to generate a displacement vector field for the registered images. The FEM correction method was compared with the “demons” algorithm on the CT images of lung and prostate patients. The performance of the FEM correction relating to the “demons” registration was analyzed based on the physical property of their deformation maps, and quantitatively evaluated through a benchmark model developed specifically for this study. Compared to the benchmark model, the “demons” registration has the maximum error of 1.2 cm, which can be corrected by the FEM method to 0.4 cm, and the average error of the “demons” registration is reduced from 0.17 cm to 0.11 cm. For the CT images of lung and prostate patients, the deformation maps generated by the “demons” algorithm were found unrealistic at several places. In these places, the displacement differences between the “demons” registrations and their FEM corrections were found in the range of 0.4 cm and 1.1cm. The mesh refinement and FEM simulation were implemented in a single thread application which requires about 45 minutes of computation time on a 2.6 GH computer. This study has demonstrated that the finite element method can be integrated with intensity-based image registration algorithms to improve their registration accuracy, especially in low-contrast regions. PMID:22581269

SPLASH (PLA2IID), a novel member of phospholipase A2 family, is associated with lymphotoxin deficiency.

PubMed

Shakhov, A N; Rubtsov, A V; Lyakhov, I G; Tumanov, A V; Nedospasov, S A

2000-02-01

Lymphotoxin (LT) deficient mice have profound defects in the splenic microarchitecture associated with defective expression on certain gene products, including chemokines. By using subtraction cloning of splenic cDNA from wild-type and LT alpha or TNF/LT alpha double deficient mice we isolated a novel murine gene encoding a secretory type phospholipase A2, called SPLASH. The two major alternative transcripts of SPLASH gene are predominantly expressed in lymphoid tissues, such as spleen and lymph nodes. SPLASH maps to the distal part of chromosome 4, to which several cancer-related loci have been also mapped.

Noninvasive visualization of tumoral fibrin deposition using a peptidic fibrin-binding single photon emission computed tomography tracer.

PubMed

Starmans, Lucas W E; van Mourik, Tiemen; Rossin, Raffaella; Verel, Iris; Nicolay, Klaas; Grüll, Holger

2015-06-01

Fibrin deposition plays an important role in the formation of mature tumor stroma and provides a facilitating scaffold for tumor angiogenesis. This study investigates the potential of the (111)In-labeled fibrin-binding peptide EPep for SPECT imaging of intratumoral fibrin deposition. (111)In-EPep and negative control (111)In-NCEPep were synthesized and characterized in vitro. In vivo SPECT images and ex vivo biodistribution profiles and autoradiographs were obtained in a fibrin-rich BT-20 breast cancer mouse model. Furthermore, biodistribution profiles were obtained in the fibrin-poor MDA-MD-231 model. In vitro, (111)In-EPep displayed significantly more binding than (111)In-NCEPep toward human and mouse derived fibrin. SPECT/CT images displayed a marked SPECT signal in the tumor area for BT-20 tumor bearing mice injected with EPep but not for mice injected with NCEPep. Biodistribution profiles of BT-20 tumor bearing mice 3 h post-tracer injection showed significantly higher tumor uptake for EPep with respect to NCEPep (0.39 ± 0.14 and 0.11 ± 0.03% ID g(-1), respectively), whereas uptake in other organs was similar for EPep and NCEPep. Autoradiography of BT-20 tumor sections displayed a high signal for EPep which colocalized with intratumoral fibrin deposits. Histological evaluation of MDA-MB-231 tumor sections displayed no significant tumor stroma and only minute fibrin deposits. Biodistribution profiles in MDA-MB-231 tumor bearing mice 3 h post-injection showed EPep tumor uptake (0.14 ± 0.04% ID g(-1)) which was significantly lower with respect to EPep BT-20 tumor uptake, indicating fibrin-specificity of EPep tumoral uptake. In conclusion, this work demonstrates the potential of EPep SPECT imaging for visualization of tumoral fibrin deposition.

Docetaxel-loaded PLGA and PLGA-PEG nanoparticles for intravenous application: pharmacokinetics and biodistribution profile

PubMed Central

Rafiei, Pedram; Haddadi, Azita

2017-01-01

Docetaxel is a highly potent anticancer agent being used in a wide spectrum of cancer types. There are important matters of concern regarding the drug’s pharmacokinetics related to the conventional formulation. Poly(lactide-co-glycolide) (PLGA) is a biocompatible/biodegradable polymer with variable physicochemical characteristics, and its application in human has been approved by the United States Food and Drug Administration. PLGA gives polymeric nanoparticles with unique drug delivery characteristics. The application of PLGA nanoparticles (NPs) as intravenous (IV) sustained-release delivery vehicles for docetaxel can favorably modify pharmacokinetics, biofate, and pharmacotherapy of the drug in cancer patients. Surface modification of PLGA NPs with poly(ethylene glycol) (PEG) can further enhance NPs’ long-circulating properties. Herein, an optimized fabrication approach has been used for the preparation of PLGA and PLGA–PEG NPs loaded with docetaxel for IV application. Both types of NP formulations demonstrated in vitro characteristics that were considered suitable for IV administration (with long-circulating sustained-release purposes). NP formulations were IV administered to an animal model, and docetaxel’s pharmacokinetic and biodistribution profiles were determined and compared between study groups. PLGA and PEGylated PLGA NPs were able to modify the pharmacokinetics and biodistribution of docetaxel. Accordingly, the mode of changes made to pharmacokinetics and biodistribution of docetaxel is attributed to the size and surface properties of NPs. NPs contributed to increased blood residence time of docetaxel fulfilling their role as long-circulating sustained-release drug delivery systems. Surface modification of NPs contributed to more pronounced docetaxel blood concentration, which confirms the role of PEG in conferring long-circulation properties to NPs. PMID:28184163

Effects of Glycosylation on Biodistribution and Imaging Quality of Necrotic Myocardium of Iodine-131-Labeled Sennidins.

PubMed

Li, Ling; Zhang, Dongjian; Yang, Shengwei; Song, Shaoli; Li, Jindian; Wang, Qin; Wang, Cong; Feng, Yuanbo; Ni, Yicheng; Zhang, Jian; Liu, Wei; Yin, Zhiqi

2016-12-01

Sennidins are necrosis-avid agents for noninvasive assessment of myocardial viability which is important for patients with myocardial infarction (MI). However, high accumulation of radioactivity in the liver interferes with the assessment of myocardial viability. In this study, we compared sennidins with sennosides to investigate the effects of glycosylation on biodistribution and imaging quality of sennidins. Sennidin A (SA), sennidin B (SB), sennoside A (SSA), and sennoside B (SSB) were labeled with I-131. In vitro binding to necrotic cells and hepatic cells and in vivo biodistribution in rats with muscular necrosis were evaluated by gamma counting, autoradiography, and histopathology. Single photon emission computed tomography/computed tomography (SPECT/CT) images were acquired in rats with acute MI. The uptake of [ 131 I]SA, [ 131 I]SSA, [ 131 I]SB, and [ 131 I]SSB in necrotic cells was significantly higher than that in viable cells (p < 0.05). Hepatic cells uptake of [ 131 I]SSA and [ 131 I]SSB were 7-fold and 10-fold lower than that of corresponding [ 131 I]SA and [ 131 I]SB, respectively. The biodistribution data showed that the radioactivities in the liver and feces were significantly lower with [ 131 I]sennosides than those with [ 131 I]sennidins (p < 0.01). Autoradiography showed preferential accumulation of these four radiotracers in necrotic areas of muscle, confirmed by histopathology. SPECT/CT imaging studies showed better image quality with [ 131 I]SSB than with [ 131 I]SB due to less liver interference. Glycosylation significantly decreased the liver uptake and improved the quality of cardiac imaging. [ 131 I]SSB may serve as a promising necrosis-avid agent for noninvasive assessment of myocardial viability.

Biodistribution and toxicological study of PEGylated single-wall carbon nanotubes in the zebrafish (Danio rerio) nervous system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weber, Gisele E.B.; Dal Bosco, Lidiane; Programa de Pós-graduação em Ciências Fisiológicas–Fisiologia Animal Comparada, FURG, Rio Grande, RS, 96210-900

Nanotechnology has been proven to be increasingly compatible with pharmacological and biomedical applications. Therefore, we evaluated the biological interactions of single-wall carbon nanotubes functionalized with polyethylene glycol (SWNT-PEG). For this purpose, we analyzed biochemical, histological, behavioral and biodistribution parameters to understand how this material behaves in vitro and in vivo using the fish Danio rerio (zebrafish) as a biological model. The in vitro results for fish brain homogenates indicated that SWNT-PEG had an effect on lipid peroxidation and GSH (reduced glutathione) content. However, after intraperitoneal exposure, SWNT-PEG proved to be less biocompatible and formed aggregates, suggesting that the PEG usedmore » for the nanoparticle functionalization was of an inappropriate size for maintaining product stability in a biological environment. This problem with functionalization may have contributed to the low or practically absent biodistribution of SWNT-PEG in zebrafish tissues, as verified by Raman spectroscopy. There was an accumulation of material in the abdominal cavity that led to inflammation and behavioral disturbances, as evaluated by a histological analysis and an open field test, respectively. These results provide evidence of a lack of biocompatibility of SWNTs modified with short chain PEGs, which leads to the accumulation of the material, tissue damage and behavioral alterations in the tested subjects. - Highlights: • In vitro brain exposure diminished lipid peroxidation. • In vitro brain exposure depletes the GSH content. • SWNT-PEG was not biocompatible and formed aggregates after the exposure. • Practically absent biodistribution of SWNT-PEG was observed by Raman spectroscopy. • SWNT-PEG exposure lead to tissue damage and inflammatory responses.« less

Transduction of Photoreceptors With Equine Infectious Anemia Virus Lentiviral Vectors: Safety and Biodistribution of StarGen for Stargardt Disease

PubMed Central

Binley, Katie; Widdowson, Peter; Loader, Julie; Kelleher, Michelle; Iqball, Sharifah; Ferrige, Georgina; de Belin, Jackie; Carlucci, Marie; Angell-Manning, Diana; Hurst, Felicity; Ellis, Scott; Miskin, James; Fernandes, Alcides; Wong, Paul; Allikmets, Rando; Bergstrom, Christopher; Aaberg, Thomas; Yan, Jiong; Kong, Jian; Gouras, Peter; Prefontaine, Annick; Vezina, Mark; Bussieres, Martin; Naylor, Stuart; Mitrophanous, Kyriacos A.

2013-01-01

Purpose. StarGen is an equine infectious anemia virus (EIAV)-based lentiviral vector that expresses the photoreceptor-specific adenosine triphosphate (ATP)-binding cassette transporter (ABCA4) protein that is mutated in Stargardt disease (STGD1), a juvenile macular dystrophy. EIAV vectors are able to efficiently transduce rod and cone photoreceptors in addition to retinal pigment epithelium in the adult macaque and rabbit retina following subretinal delivery. The safety and biodistribution of StarGen following subretinal delivery in macaques and rabbits was assessed. Methods. Regular ophthalmic examinations, IOP measurements, ERG responses, and histopathology were carried out in both species to compare control and vector-treated eyes. Tissue and fluid samples were obtained to evaluate the persistence, biodistribution, and shedding of the vector following subretinal delivery. Results. Ophthalmic examinations revealed a slightly higher level of inflammation in StarGen compared with control treated eyes in both species. However, inflammation was transient and no overt toxicity was observed in StarGen treated eyes and there were no abnormal clinical findings. There was no StarGen-associated rise in IOP or abnormal ERG response in either rabbits or macaques. Histopathologic examination of the eyes did not reveal any detrimental changes resulting from subretinal administration of StarGen. Although antibodies to StarGen vector components were detected in rabbit but not macaque serum, this immunologic response did not result in any long-term toxicity. Biodistribution analysis demonstrated that the StarGen vector was restricted to the ocular compartment. Conclusions. In summary, these studies demonstrate StarGen to be well tolerated and localized following subretinal administration. PMID:23620430

Preclinical Evaluation of 68Ga-DOTA-Minigastrin for the Detection of Cholecystokinin-2/Gastrin Receptor–Positive Tumors

PubMed Central

Brom, Maarten; Joosten, Lieke; Laverman, Peter; Oyen, Wim J.G.; Béhé, Martin; Gotthardt, Martin; Boerman, Otto C.

2011-01-01

In comparison to somatostatin receptor scintigraphy, gastrin receptor scintigraphy using 111In-DTPA-minigastrin (MG0) showed added value in diagnosing neuroendocrine tumors. We investigated whether the 68Ga-labeled gastrin analogue DOTA-MG0 is suited for positron emission tomography (PET), which could improve image quality. Targeting of cholecystokinin-2 (CCK2)/gastrin receptor–positive tumor cells with DOTA-MG0 labeled with either 111In or 68Ga in vitro was investigated using the AR42J rat tumor cell line. Biodistribution was examined in BALB/c nude mice with a subcutaneous AR42J tumor. In vivo PET imaging was performed using a preclinical PET–computed tomographic scanner. DOTA-MG0 showed high receptor affinity in vitro. Biodistribution studies revealed high tumor uptake of 68Ga-DOTA-MG0: 4.4 ± 1.3 %ID/g at 1 hour postinjection. Coadministration of an excess unlabeled peptide blocked the tumor uptake (0.7 ± 0.1 %ID/g), indicating CCK2/gastrin receptor–mediated uptake (p = .0005). The biodistribution of 68Ga-DOTA-MG0 was similar to that of 111In-DOTA-MG0. Subcutaneous and intraperitoneal tumors were clearly visualized by small-animal PET imaging with 5 MBq 68Ga-DOTA-MG0. 111In- and 68Ga-labeled DOTA-MG0 specifically accumulate in CCK2/gastrin receptor–positive AR42J tumors with similar biodistribution apart from the kidneys. AR42J tumors were clearly visualized by microPET. Therefore, 68Ga-DOTA-MG0 is a promising tracer for PET imaging of CCK2/gastrin receptor–positive tumors in humans. PMID:21439259

Preclinical evaluation of 68Ga-DOTA-minigastrin for the detection of cholecystokinin-2/gastrin receptor-positive tumors.

PubMed

Brom, Maarten; Joosten, Lieke; Laverman, Peter; Oyen, Wim J G; Béhé, Martin; Gotthardt, Martin; Boerman, Otto C

2011-04-01

In comparison to somatostatin receptor scintigraphy, gastrin receptor scintigraphy using 111In-DTPA-minigastrin (MG0) showed added value in diagnosing neuroendocrine tumors. We investigated whether the 68Ga-labeled gastrin analogue DOTA-MG0 is suited for positron emission tomography (PET), which could improve image quality. Targeting of cholecystokinin-2 (CCK2)/gastrin receptor-positive tumor cells with DOTA-MG0 labeled with either 111In or 68Ga in vitro was investigated using the AR42J rat tumor cell line. Biodistribution was examined in BALB/c nude mice with a subcutaneous AR42J tumor. In vivo PET imaging was performed using a preclinical PET-computed tomographic scanner. DOTA-MG0 showed high receptor affinity in vitro. Biodistribution studies revealed high tumor uptake of 68Ga-DOTA-MG0: 4.4 ± 1.3 %ID/g at 1 hour postinjection. Coadministration of an excess unlabeled peptide blocked the tumor uptake (0.7 ± 0.1 %ID/g), indicating CCK2/gastrin receptor-mediated uptake (p  =  .0005). The biodistribution of 68Ga-DOTA-MG0 was similar to that of 111In-DOTA-MG0. Subcutaneous and intraperitoneal tumors were clearly visualized by small-animal PET imaging with 5 MBq 68Ga-DOTA-MG0. 111In- and 68Ga-labeled DOTA-MG0 specifically accumulate in CCK2/gastrin receptor-positive AR42J tumors with similar biodistribution apart from the kidneys. AR42J tumors were clearly visualized by microPET. Therefore, 68Ga-DOTA-MG0 is a promising tracer for PET imaging of CCK2/gastrin receptor-positive tumors in humans.

Fluorescent carbon nanoparticles derived from natural materials of mango fruit for bio-imaging probes

NASA Astrophysics Data System (ADS)

Jeong, Chan Jin; Roy, Arup Kumer; Kim, Sung Han; Lee, Jung-Eun; Jeong, Ji Hoon; Insik; Park, Sung Young

2014-11-01

Water soluble fluorescent carbon nanoparticles (FCP) obtained from a single natural source, mango fruit, were developed as unique materials for non-toxic bio-imaging with different colors and particle sizes. The prepared FCPs showed blue (FCP-B), green (FCP-G) and yellow (FCP-Y) fluorescence, derived by the controlled carbonization method. The FCPs demonstrated hydrodynamic diameters of 5-15 nm, holding great promise for clinical applications. The biocompatible FCPs demonstrated great potential in biological fields through the results of in vitro imaging and in vivo biodistribution. Using intravenously administered FCPs with different colored particles, we precisely defined the clearance and biodistribution, showing rapid and efficient urinary excretion for safe elimination from the body. These findings therefore suggest the promising possibility of using natural sources for producing fluorescent materials.Water soluble fluorescent carbon nanoparticles (FCP) obtained from a single natural source, mango fruit, were developed as unique materials for non-toxic bio-imaging with different colors and particle sizes. The prepared FCPs showed blue (FCP-B), green (FCP-G) and yellow (FCP-Y) fluorescence, derived by the controlled carbonization method. The FCPs demonstrated hydrodynamic diameters of 5-15 nm, holding great promise for clinical applications. The biocompatible FCPs demonstrated great potential in biological fields through the results of in vitro imaging and in vivo biodistribution. Using intravenously administered FCPs with different colored particles, we precisely defined the clearance and biodistribution, showing rapid and efficient urinary excretion for safe elimination from the body. These findings therefore suggest the promising possibility of using natural sources for producing fluorescent materials. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr04805a

Direct comparison of radiation dosimetry of six PET tracers using human whole-body imaging and murine biodistribution studies.

PubMed

Sakata, Muneyuki; Oda, Keiichi; Toyohara, Jun; Ishii, Kenji; Nariai, Tadashi; Ishiwata, Kiichi

2013-04-01

We investigated the whole-body biodistributions and radiation dosimetry of five (11)C-labeled and one (18)F-labeled radiotracers in human subjects, and compared the results to those obtained from murine biodistribution studies. The radiotracers investigated were (11)C-SA4503, (11)C-MPDX, (11)C-TMSX, (11)C-CHIBA-1001, (11)C-4DST, and (18)F-FBPA. Dynamic whole-body positron emission tomography (PET) was performed in three human subjects after a single bolus injection of each radiotracer. Emission scans were collected in two-dimensional mode in five bed positions. Regions of interest were placed over organs identified in reconstructed PET images. The OLINDA program was used to estimate radiation doses from the number of disintegrations of these source organs. These results were compared with the predicted human radiation doses on the basis of biodistribution data obtained from mice by dissection. The ratios of estimated effective doses from the human-derived data to those from the mouse-derived data ranged from 0.86 to 1.88. The critical organs that received the highest absorbed doses in the human- and mouse-derived studies differed for two of the six radiotracers. The differences between the human- and mouse-derived dosimetry involved not only the species differences, including faster systemic circulation of mice and differences in the metabolism, but also measurement methodologies. Although the mouse-derived effective doses were roughly comparable to the human-derived doses in most cases, considerable differences were found for critical organ dose estimates and pharmacokinetics in certain cases. Whole-body imaging for investigation of radiation dosimetry is desirable for the initial clinical evaluation of new PET probes prior to their application in subsequent clinical investigations.

Positron emission tomography: a novel technique for investigating the biodistribution and transport of nanoparticles.

PubMed

Palko, Heather A; Fung, Jennifer Y; Louie, Angelique Y

2010-07-01

Particulate matter (PM) has been associated with serious health effects within but also outside of the pulmonary system. Therefore, there is great interest in studying the biodistribution of PM after delivery to the lung to correlate sites of extrapulmonary particle accumulation and abnormal conditions known to be associated with PM exposure. Traditional PM tracking studies have introduced nanoparticles to animal models or humans and have determined the biodistribution with gamma counting, gamma camera, and inductively coupled plasma mass spectrometry (ICP-MS). The authors here demonstrate that positron emission tomography (PET) is a powerful tool that can be employed to visualize the deposition and track the fate of nanoparticles in the mouse model. In these studies, approximately 100-nm polystyrene nanoparticles were labeled with the positron emitter 64Cu bound by the chelator (S)-2-(4-isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane-tetraacetic acid (p-SCN-Bn-DOTA). The labeled nanoparticles were instilled intratracheally into C57BL/6 mice; the initial deposition and biodistribution through 48 h was determined by PET imaging. In addition to static imaging, dynamic imaging was performed in the Sprague-Dawley rat model to demonstrate that PET can capture particle movement in pseudo-time-lapse videos. Particle deposition and clearance was clearly identified by PET, and the same animals could be imaged repeatedly without any adverse effects from anesthesia. PET has the potential to require many fewer animals than traditional methods while still providing quantitative results. In addition, the initial deposition pattern in each animal can be accurately determined and the same animal monitored over time so that data interpretation is not clouded by variations in initial deposition profiles.

Biodistribution and Immunogenicity of Allogeneic Mesenchymal Stem Cells in a Rat Model of Intraarticular Chondrocyte Xenotransplantation.

PubMed

Marquina, Maribel; Collado, Javier A; Pérez-Cruz, Magdiel; Fernández-Pernas, Pablo; Fafián-Labora, Juan; Blanco, Francisco J; Máñez, Rafael; Arufe, María C; Costa, Cristina

2017-01-01

Xenogeneic chondrocytes and allogeneic mesenchymal stem cells (MSC) are considered a potential source of cells for articular cartilage repair. We here assessed the immune response triggered by xenogeneic chondrocytes when injected intraarticularly, as well as the immunoregulatory effect of allogeneic bone marrow-derived MSC after systemic administration. To this end, a discordant xenotransplantation model was established by injecting three million porcine articular chondrocytes (PAC) into the femorotibial joint of Lewis rats and monitoring the immune response. First, the fate of MSC injected using various routes was monitored in an in vivo imaging system. The biodistribution revealed a dependency on the injection route with MSC injected intravenously (i.v.) succumbing early after 24 h and MSC injected intraperitoneally (i.p.) lasting locally for at least 5 days. Importantly, no migration of MSC to the joint was detected in rats previously injected with PAC. MSC were then administered either i.v. 1 week before PAC injection or i.p. 3 weeks after to assess their immunomodulatory function on humoral and adaptive immune parameters. Anti-PAC IgM and IgG responses were detected in all PAC-injected rats with a peak at week 2 postinjection and reactivity remaining above baseline levels by week 18. IgG2a and IgG2b were the predominant and long-lasting IgG subtypes. By contrast, no anti-MSC antibody response was detected in the cohort injected with MSC only, but infusion of MSC before PAC injection temporarily augmented the anti-PAC antibody response. Consistent with a cellular immune response to PAC in PAC-injected rats, cytokine/chemokine profiling in serum by antibody array revealed a distinct pattern relative to controls characterized by elevation of multiple markers at week 2, as well as increases in proliferation in draining lymph nodes. Notably, systemic administration of allogeneic MSC under the described conditions did not diminish the immune response. IL-2 measurements in cocultures of rat peripheral blood lymphocytes with PAC indicated that PAC injection induced some T-cell hyporesponsiveness that was not enhanced in the cohorts additionally receiving MSC. Thus, PAC injected intraarticularly in Lewis rats induced a cellular and humoral immune response that was not counteracted by the systemic administration of allogeneic MSC under the described conditions.

Biodistribution and Immunogenicity of Allogeneic Mesenchymal Stem Cells in a Rat Model of Intraarticular Chondrocyte Xenotransplantation

PubMed Central

Marquina, Maribel; Collado, Javier A.; Pérez-Cruz, Magdiel; Fernández-Pernas, Pablo; Fafián-Labora, Juan; Blanco, Francisco J.; Máñez, Rafael; Arufe, María C.; Costa, Cristina

2017-01-01

Xenogeneic chondrocytes and allogeneic mesenchymal stem cells (MSC) are considered a potential source of cells for articular cartilage repair. We here assessed the immune response triggered by xenogeneic chondrocytes when injected intraarticularly, as well as the immunoregulatory effect of allogeneic bone marrow-derived MSC after systemic administration. To this end, a discordant xenotransplantation model was established by injecting three million porcine articular chondrocytes (PAC) into the femorotibial joint of Lewis rats and monitoring the immune response. First, the fate of MSC injected using various routes was monitored in an in vivo imaging system. The biodistribution revealed a dependency on the injection route with MSC injected intravenously (i.v.) succumbing early after 24 h and MSC injected intraperitoneally (i.p.) lasting locally for at least 5 days. Importantly, no migration of MSC to the joint was detected in rats previously injected with PAC. MSC were then administered either i.v. 1 week before PAC injection or i.p. 3 weeks after to assess their immunomodulatory function on humoral and adaptive immune parameters. Anti-PAC IgM and IgG responses were detected in all PAC-injected rats with a peak at week 2 postinjection and reactivity remaining above baseline levels by week 18. IgG2a and IgG2b were the predominant and long-lasting IgG subtypes. By contrast, no anti-MSC antibody response was detected in the cohort injected with MSC only, but infusion of MSC before PAC injection temporarily augmented the anti-PAC antibody response. Consistent with a cellular immune response to PAC in PAC-injected rats, cytokine/chemokine profiling in serum by antibody array revealed a distinct pattern relative to controls characterized by elevation of multiple markers at week 2, as well as increases in proliferation in draining lymph nodes. Notably, systemic administration of allogeneic MSC under the described conditions did not diminish the immune response. IL-2 measurements in cocultures of rat peripheral blood lymphocytes with PAC indicated that PAC injection induced some T-cell hyporesponsiveness that was not enhanced in the cohorts additionally receiving MSC. Thus, PAC injected intraarticularly in Lewis rats induced a cellular and humoral immune response that was not counteracted by the systemic administration of allogeneic MSC under the described conditions. PMID:29163532

Histopathology mapping of biochemical changes in myocardial infarction by Fourier transform infrared spectral imaging.

PubMed

Yang, Tian T; Weng, Shi F; Zheng, Na; Pan, Qing H; Cao, Hong L; Liu, Liang; Zhang, Hai D; Mu, Da W

2011-04-15

Fourier transform infrared (FTIR) imaging and microspectroscopy have been extensively applied in the identification and investigation of both healthy and diseased tissues. FTIR imaging can be used to determine the biodistribution of several molecules of interest (carbohydrates, lipids, proteins) for tissue analysis, without the need for prior staining of these tissues. Molecular structure data, such as protein secondary structure and collagen triple helix exhibits, can also be obtained from the same analysis. Thus, several histopathological lesions, for example myocardial infarction, can be identified from FTIR-analyzed tissue images, the latter which can allow for more accurate discrimination between healthy tissues and pathological lesions. Accordingly, we propose FTIR imaging as a new tool integrating both molecular and histopathological assessment to investigate the degree of pathological changes in tissues. In this study, myocardial infarction is presented as an illustrative example of the wide potential of FTIR imaging for biomedical applications. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Intelligent self-organization methods for wireless ad hoc sensor networks based on limited resources

NASA Astrophysics Data System (ADS)

Hortos, William S.

2006-05-01

A wireless ad hoc sensor network (WSN) is a configuration for area surveillance that affords rapid, flexible deployment in arbitrary threat environments. There is no infrastructure support and sensor nodes communicate with each other only when they are in transmission range. To a greater degree than the terminals found in mobile ad hoc networks (MANETs) for communications, sensor nodes are resource-constrained, with limited computational processing, bandwidth, memory, and power, and are typically unattended once in operation. Consequently, the level of information exchange among nodes, to support any complex adaptive algorithms to establish network connectivity and optimize throughput, not only deplete those limited resources and creates high overhead in narrowband communications, but also increase network vulnerability to eavesdropping by malicious nodes. Cooperation among nodes, critical to the mission of sensor networks, can thus be disrupted by the inappropriate choice of the method for self-organization. Recent published contributions to the self-configuration of ad hoc sensor networks, e.g., self-organizing mapping and swarm intelligence techniques, have been based on the adaptive control of the cross-layer interactions found in MANET protocols to achieve one or more performance objectives: connectivity, intrusion resistance, power control, throughput, and delay. However, few studies have examined the performance of these algorithms when implemented with the limited resources of WSNs. In this paper, self-organization algorithms for the initiation, operation and maintenance of a network topology from a collection of wireless sensor nodes are proposed that improve the performance metrics significant to WSNs. The intelligent algorithm approach emphasizes low computational complexity, energy efficiency and robust adaptation to change, allowing distributed implementation with the actual limited resources of the cooperative nodes of the network. Extensions of the algorithms from flat topologies to two-tier hierarchies of sensor nodes are presented. Results from a few simulations of the proposed algorithms are compared to the published results of other approaches to sensor network self-organization in common scenarios. The estimated network lifetime and extent under static resource allocations are computed.

Sentinel lymph node navigation surgery for gastric cancer: Does it really benefit the patient?

PubMed

Tani, Tohru; Sonoda, Hiromichi; Tani, Masaji

2016-03-14

Sentinel lymph node (SLN) navigation surgery is accepted as a standard treatment procedure for malignant melanoma and breast cancer. However, the benefit of reduced lymphadenectomy based on SLN examination remains unclear in cases of gastric cancer. Here, we review previous studies to determine whether SLN navigation surgery is beneficial for gastric cancer patients. Recently, a large-scale prospective study from the Japanese Society of Sentinel Node Navigation Surgery reported that the endoscopic dual tracer method, using a dye and radioisotope for SLN biopsy, was safe and effective when applied to cases of superficial and relatively small gastric cancers. SLN mapping with SLN basin dissection was preferred for early gastric cancer since it is minimally invasive. However, previous studies reported that limited gastrectomy and lymphadenectomy may not improve the patient's postoperative quality of life (QOL). As a result, the benefit of SLN navigation surgery for gastric cancer patients, in terms of their QOL, is limited. Thus, endoscopic and laparoscopic limited gastrectomy combined with SLN navigation surgery has the potential to become the standard minimally invasive surgery in early gastric cancer.