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https://www.readbyqxmd.com/read/28636776/facile-synthesis-and-chain-length-dependent-optical-and-structural-properties-of-diketopyrrolopyrrole-based-oligomers
#1
Satish Patil, Tushita Mukhopadhyay, Boregowda Puttaraju, Palas Roy, Jyotishman Dasgupta, Andreas Meyer
Here we report the synthesis, optical properties and solid-state packing of monodisperse oligomers of DPP up to five repeating units. Optical properties of DPP-oligomers in solution and solid state were investigated by a combination of steady-state, and transient spectroscopy. Transient absorption spectroscopy and time-correlated single photon counting (TCSPC) measurements show that the fluorescence lifetime decreases with increase in the oligomer size from monomer to trimer, thereby reaching saturation for pentameric DPP oligomer...
June 21, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28631404/structural-connectivity-differences-in-motor-network-between-tremor-dominant-and-nontremor-parkinson-s-disease
#2
Gaetano Barbagallo, Maria Eugenia Caligiuri, Gennarina Arabia, Andrea Cherubini, Angela Lupo, Rita Nisticò, Maria Salsone, Fabiana Novellino, Maurizio Morelli, Giuseppe Lucio Cascini, Domenico Galea, Aldo Quattrone
Motor phenotypes of Parkinson's disease (PD) are recognized to have different prognosis and therapeutic response, but the neural basis for this clinical heterogeneity remains largely unknown. The main aim of this study was to compare differences in structural connectivity metrics of the main motor network between tremor-dominant and nontremor PD phenotypes (TD-PD and NT-PD, respectively) using probabilistic tractography-based network analysis. A total of 63 PD patients (35 TD-PD patients and 28 NT-PD patients) and 30 healthy controls underwent a 3 T MRI...
June 20, 2017: Human Brain Mapping
https://www.readbyqxmd.com/read/28630395/cerebral-infarction-by-paradoxical-gas-embolism-during-laparoscopic-liver-resection-with-injury-of-the-hepatic-vessels-in-a-patient-without-a-right-to-left-systemic-shunt
#3
Toshiyasu Kawahara, Masahiro Hagiwara, Hiroyuki Takahashi, Mariko Tanaka, Koji Imai, Jun Sawada, Takayuki Kunisawa, Hiroyuki Furukawa
BACKGROUND Carbon dioxide (CO2) is believed to be the safest gas for laparoscopic surgery, which is a standard procedure. We experienced severe cerebral infarction caused by paradoxical CO2 embolism during laparoscopic liver resection with injury of the hepatic vessels despite the absence of a right-to-left systemic shunt. CASE REPORT A 60-year-old man was diagnosed with hepatocellular carcinoma in the right hepatic lobe secondary to alcoholic liver disease. We planned the laparoscopy-assisted liver resection...
June 20, 2017: American Journal of Case Reports
https://www.readbyqxmd.com/read/28623512/phosphatidylethanolamine-targeting-for-cell-death-imaging-in-early-treatment-response-evaluation-and-disease-diagnosis
#4
REVIEW
Filipe Elvas, Sigrid Stroobants, Leonie Wyffels
Phosphatidylethanolamine (PE) is one of the most abundant phospholipids in mammalian plasma membranes. In healthy cells, PE resides predominantly in the inner leaflet of the cell membrane. In dead or dying cells on the other hand, PE is externalized to the outer leaflet of the plasma membrane. The exposure of PE on the cell surface has therefore become an attractive target for the molecular imaging of cell death using single-photon emission computed tomography (SPECT) and positron emission tomography (PET)...
June 16, 2017: Apoptosis: An International Journal on Programmed Cell Death
https://www.readbyqxmd.com/read/28623409/evaluation-of-bone-viability-in-patients-after-girdlestone-arthroplasty-comparison-of-bone-spect-ct-and-mri
#5
G Diederichs, P Hoppe, F Collettini, G Wassilew, B Hamm, W Brenner, M R Makowski
PURPOSE: To test the diagnostic performance of bone SPECT/CT and MRI for the evaluation of bone viability in patients after girdlestone-arthroplasty with histopathology used as gold standard. MATERIALS AND METHODS: In this cross-sectional study, patients after girdlestone-arthroplasty were imaged with single-photon-emission-computed-tomography/computed-tomography (SPECT/CT) bone-scans using 99mTc-DPD. Additionally, 1.5 T MRI was performed with turbo-inversion-recovery-magnitude (TIRM), contrast-enhanced T1-fat sat (FS) and T1-mapping...
June 16, 2017: Skeletal Radiology
https://www.readbyqxmd.com/read/28622946/estimation-of-myocardial-flow-reserve-utilizing-an-ultrafast-cardiac-spect-comparison-with-coronary-angiography-fractional-flow-reserve-and-the-syntax-score
#6
Masao Miyagawa, Yoshiko Nishiyama, Teruyoshi Uetani, Akiyoshi Ogimoto, Shuntaro Ikeda, Hayato Ishimura, Emiri Watanabe, Rami Tashiro, Yuki Tanabe, Teruhito Kido, Akira Kurata, Teruhito Mochizuki
BACKGROUND: Quantitative assessment of myocardial flow reserve (MFR) by single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is challenging but may facilitate evaluation of multi-vessel coronary artery disease (CAD). METHODS: We enrolled 153 patients with suspected or known CAD, referred for pharmacological stress MPI. They underwent a (99m)Tc-perfusion stress/rest SPECT with an ultrafast cadmium-zinc-telluride (CZT) camera. Dynamic data were acquired and time-activity curves fitted to a 1-tissue compartment analysis with input function...
June 13, 2017: International Journal of Cardiology
https://www.readbyqxmd.com/read/28622166/quantitative-analysis-of-iodine-image-of-dual-energy-computed-tomography-at-rest-comparison-with-99mtc-tetrofosmin-stress-rest-single-photon-emission-computed-tomography-myocardial-perfusion-imaging-as-the-reference-standard
#7
Takehiro Nakahara, Takuji Toyama, Masahiro Jinzaki, Ryotaro Seki, Yuichiro Saito, Tetsuya Higuchi, Minoru Yamada, Masashi Arai, Yoshito Tsushima, Sachio Kuribayashi, Masahiko Kurabayashi
PURPOSE: Dual-energy computed tomography (DECT) can be used for visual determination of iodine distribution in the myocardium (iodine image); however, the accuracy and reproducibility of the process remains debatable. Because of the low contrast-to-noise ratio of CT, we hypothesized that quantitative measurement may be more accurate for detecting myocardial ischemia. In this study, we evaluated our quantitative method by comparing it with visual analysis using Tc-tetrofosmin (TF) stress-rest single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) as the reference standard...
June 15, 2017: Journal of Thoracic Imaging
https://www.readbyqxmd.com/read/28621982/quantum-nonlinear-optics-with-a-germanium-vacancy-color-center-in-a-nanoscale-diamond-waveguide
#8
M K Bhaskar, D D Sukachev, A Sipahigil, R E Evans, M J Burek, C T Nguyen, L J Rogers, P Siyushev, M H Metsch, H Park, F Jelezko, M Lončar, M D Lukin
We demonstrate a quantum nanophotonics platform based on germanium-vacancy (GeV) color centers in fiber-coupled diamond nanophotonic waveguides. We show that GeV optical transitions have a high quantum efficiency and are nearly lifetime broadened in such nanophotonic structures. These properties yield an efficient interface between waveguide photons and a single GeV center without the use of a cavity or slow-light waveguide. As a result, a single GeV center reduces waveguide transmission by 18±1% on resonance in a single pass...
June 2, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28621978/self-similar-nanocavity-design-with-ultrasmall-mode-volume-for-single-photon-nonlinearities
#9
Hyeongrak Choi, Mikkel Heuck, Dirk Englund
We propose a photonic crystal nanocavity design with self-similar electromagnetic boundary conditions, achieving ultrasmall mode volume (V_{eff}). The electric energy density of a cavity mode can be maximized in the air or dielectric region, depending on the choice of boundary conditions. We illustrate the design concept with a silicon-air one-dimensional photon crystal cavity that reaches an ultrasmall mode volume of V_{eff}∼7.01×10^{-5}λ^{3} at λ∼1550  nm. We show that the extreme light concentration in our design can enable ultrastrong Kerr nonlinearities, even at the single-photon level...
June 2, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28620211/multimode-quantum-states-with-single-photons-carrying-orbital-angular-momentum
#10
Xin-Bing Song, Shi-Yao Fu, Xiong Zhang, Zhen-Wei Yang, Qiang Zeng, Chunqing Gao, Xiangdong Zhang
We propose and experimentally demonstrate a scheme for generating multimode quantum states with single photons carrying orbital angular momentum (OAM). Various quantum states have been realized by superposing multiple OAM modes of single photons in two possible paths. These quantum states exhibit NOON-like "super-resolving" interference behavior for the multiple OAM modes of single photons. Compared with the NOON states using many photons, these states are not only easily prepared, but also robust to photon losses...
June 15, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28618966/-68-ga-177-lu-labeled-dota-tate-shows-similar-imaging-and-biodistribution-in-neuroendocrine-tumor-model
#11
Fei Liu, Hua Zhu, Jiangyuan Yu, Xuedi Han, Qinghua Xie, Teli Liu, Chuanqin Xia, Nan Li, Zhi Yang
Somatostatin receptors are overexpressed in neuroendocrine tumors, whose endogenous ligands are somatostatin. DOTA-TATE is an analogue of somatostatin, which shows high binding affinity to somatostatin receptors. We aim to evaluate the (68)Ga/(177)Lu-labeling DOTA-TATE kit in neuroendocrine tumor model for molecular imaging and to try human-positron emission tomography/computed tomography imaging of (68)Ga-DOTA-TATE in neuroendocrine tumor patients. DOTA-TATE kits were formulated and radiolabeled with (68)Ga/(177)Lu for (68)Ga/(177)Lu-DOTA-TATE (M-DOTA-TATE)...
June 2017: Tumour Biology: the Journal of the International Society for Oncodevelopmental Biology and Medicine
https://www.readbyqxmd.com/read/28615899/clinical-and-imaging-study-of-isolated-and-mixed-rest-and-action-tremor-essential-tremor-versus-parkinson-s-disease
#12
Sandro Zambito Marsala, Michele Pistacchi, Manuela Gioulis, Franco Ferracci, Livio Capus
BACKGROUND: Some patients present an unusual association of both action tremor (AT) and rest tremor (RT) making the differential diagnosis between essential tremor (ET) and Parkinson's disease (PD) difficult. AIM: To investigate this particular clinical picture trying to focus on possible peculiar clinical inferences. PATIENTS AND METHODS: Twenty-three patients with atypical tremor syndrome were selected for the study. They underwent neurological examination, neuroimaging study, and brain DaTSCAN single-photon emission computed tomography...
April 2017: Annals of Indian Academy of Neurology
https://www.readbyqxmd.com/read/28614134/value-of-99mtc-mibi-spect-ct-parathyroid-imaging-and-ultrasonography-for-concomitant-thyroid-carcinoma
#13
Rui Guo, Jiqiu Wang, Min Zhang, Miao Zhang, Hongping Meng, Yifan Zhang, Biao Li
PURPOSE: We aimed to assess the frequency of carcinoma in cases with suspected parathyroid adenoma and test the value of Tc-methoxyisobutylisonitrile (Tc-MIBI) single-photon emission computed tomography/computed tomography (SPECT/CT) parathyroid imaging and neck ultrasonography in detecting concomitant thyroid carcinoma. PATIENTS AND METHODS: We enrolled 741 patients with clinically suspected parathyroid adenoma who underwent Tc-MIBI planer scans and SPECT/CT of the skull base, neck, and thorax; patients also underwent ultrasonography within 1 month before SPECT/CT...
June 13, 2017: Nuclear Medicine Communications
https://www.readbyqxmd.com/read/28613848/near-infrared-optical-imaging-of-necrotic-cells-by-photostable-lanthanide-based-metallacrowns
#14
Ivana Martinić, Svetlana V Eliseeva, Tu N Nguyen, Vincent L Pecoraro, Stéphane Petoud
Sensitive detection of cell necrosis is crucial for the determination of cell viability. Because of its high resolution at the cellular level and sensitivity, optical imaging is highly attractive for identifying cell necrosis. However, challenges associated with this technique remain present such as the rapid photobleaching of several types of organic fluorophores and/or the interference generated by biological autofluorescence. Herein, we synthesized novel biologically compatible Zn(2+)/Ln(3+) metallacrowns (MCs) that possess attractive near-infrared (NIR) emission and are highly photostable...
June 14, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28613198/lu-177-psma-617-prostate-specific-membrane-antigen-inhibitor-therapy-in-patients-with-castration-resistant-prostate-cancer-stability-bio-distribution-and-dosimetry
#15
Levent Kabasakal, Türkay Toklu, Nami Yeyin, Emre Demirci, Mohammad Abuqbeitah, Meltem Ocak, Aslan Aygün, Emre Karayel, Hüseyin Pehlivanoğlu, Nalan Alan Selçuk
OBJECTIVE: The aim of the study was to estimate the radiation-absorbed doses and to study the in vivo and in vitro stability as well as pharmacokinetic characteristics of lutetium-177 (Lu-177) prostate-specific membrane antigen (PSMA)-617. METHODS: For this purpose, 7 patients who underwent Lu-177-PSMA therapy were included into the study. The injected Lu-177-PSMA-617 activity ranged from 3.6 to 7.4 GBq with a mean of 5.2±1.8 GBq. The stability of radiotracer in saline was calculated up to 48 h...
June 1, 2017: Molecular Imaging and Radionuclide Therapy
https://www.readbyqxmd.com/read/28611426/radioiodination-of-bodipy-and-its-application-to-a-nuclear-and-optical-dual-functional-labeling-agent-for-proteins-and-peptides
#16
Masahiro Ono, Hiroyuki Watanabe, Yuki Ikehata, Ning Ding, Masashi Yoshimura, Kohei Sano, Hideo Saji
In molecular imaging research, the development of multimodal imaging probes has recently attracted much attention. In the present study, we prepared radioiodinated BODIPY and applied it as a nuclear and optical dual functional labeling agent for proteins and peptides. We designed and synthesized [(125)I]BODIPY with a N-hydroxysuccinimide (NHS) ester, and evaluated its utility as a nuclear and fluorescent dual labeling agent for proteins and peptides. In the radioiodination reaction of BODIPY-NHS with [(125)I]NaI, [(125)I]BODIPY-NHS was obtained at a 48% radiochemical yield...
June 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28611245/optimization-of-spect-measurement-of-myocardial-blood-flow-with-corrections-for-attenuation-motion-and-blood-binding-compared-to-pet
#17
R Glenn Wells, Brian Marvin, Marlie Poirier, Jennifer M Renaud, Robert A deKemp, Terrence D Ruddy
Myocardial blood flow (MBF) and flow reserve (MFR) measured with positron emission tomography (PET) have clinical value. Single-photon emission computed tomography (SPECT) cameras with solid-state detectors can obtain dynamic images for measurement of MBF and MFR. In this study, SPECT measurements of MBF made using (99m)Tc-tetrofosmin were compared to PET in the same patients. Methods: Thirty-one patients had PET MBF rest-stress studies performed with (82)Rb or (13)N- ammonia within one month of their SPECT...
June 13, 2017: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
https://www.readbyqxmd.com/read/28611231/validation-of-the-left-ventricular-ejection-fraction-with-iq-spect-system-in-small-heart-patients
#18
Hiroto Yoneyama, Takayuki Shibutani, Takahiro Konishi, Asuka Mizutani, Hashimoto Ryosuke, Masahisa Onoguchi, Koichi Okuda, Shinro Matsuo, Kenichi Nakajima, Kinuya Seigo
The IQ-SPECT system equipped with a multifocal (SMARTZOOM) collimator using an ordered subset conjugate gradient minimization (OSCGM) algorithm reduces the acquisition time of myocardial perfusion imaging (MPI) compared to conventional gamma cameras equipped with low-energy high-resolution (LEHR) collimators. We compared IQ-SPECT with a conventional single-photon emission computed tomography (SPECT) system for estimating the left ventricular ejection fraction (LVEF) in small-heart patients. Methods: The study group consisted of 98 consecutive patients who underwent a 1-day stress-rest MPI study with a (99m)Tc-labeled agent for preoperative risk assessment...
June 13, 2017: Journal of Nuclear Medicine Technology
https://www.readbyqxmd.com/read/28611079/elevated-camp-improves-signal-to-noise-ratio-in-amphibian-rod-photoreceptors
#19
Luba A Astakhova, Darya A Nikolaeva, Tamara V Fedotkina, Victor I Govardovskii, Michael L Firsov
The absolute sensitivity of vertebrate retinas is set by a background noise, called dark noise, which originates from several different cell types and is generated by different molecular mechanisms. The major share of dark noise is produced by photoreceptors and consists of two components, discrete and continuous. Discrete noise is generated by spontaneous thermal activations of visual pigment. These events are undistinguishable from real single-photon responses (SPRs) and might be considered an equivalent of the signal...
June 13, 2017: Journal of General Physiology
https://www.readbyqxmd.com/read/28608446/dual-addressing-of-thymidine-synthesis-pathways-for-effective-targeting-of-proliferating-melanoma
#20
Tara Miran, Andreas T J Vogg, Laila El Moussaoui, Hans-Jürgen Kaiser, Natascha Drude, Verena von Felbert, Felix M Mottaghy, Agnieszka Morgenroth
Here, we examined the potential of blocking the thymidine de novo synthesis pathways for sensitizing melanoma cells to the nucleoside salvage pathway targeting endogenous DNA irradiation. Expression of key nucleotide synthesis and proliferation enzymes thymidylate synthase (TS) and thymidine kinase 1 (TK1) was evaluated in differentiated (MITF(high) [microphthalmia-associated transcription factor] IGR1) and invasive (MITF(medium) IGR37) melanoma cells. For inhibition of de novo pathways cells were incubated either with an irreversible TS inhibitor 5-fluoro-2'-deoxyuridine (FdUrd) or with a competitive dihydrofolate-reductase (DHFR) inhibitor methotrexate (MTX)...
June 13, 2017: Cancer Medicine
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