Magnetic nanosensors optimized for rapid and reversible self-assembly

Magnetic nanoparticle-based sensors for MRI have been accelerated to a timescale of seconds using densely-functionalized particles of small size. Parameters that increase response rates also result in large nuclear magnetic relaxation rate and light scattering changes, allowing signals to be detected almost immediately after changes in calcium concentration.United States. National Institutes of Health (DP2-OD2114)United States. National Institutes of Health (R01-DA28299)United States. National Institutes of Health (R01-NS76462

Forenzički aspekti postmortalne analize transferina s nedostatkom ugljenih hidrata kao markera zloupotrebe alkohola

Introduction Carbohydrate-deficient transferrin (CDT) has been suggested as one of alcohol abuse indicators having produced good results in forensic medicine for years. Objective The aim of the study was to identify correlation between present methodology of alcohol abuse diagnosis at autopsy (macroscopic and microscopic findings) and CDT examination using the method of isoelectrofocusing (IEF) in polyacrylamide gel electrophoresis (PAGE). We also analyzed if the time interval between the moment of death and blood sample collection influences CDT findings. Methods The method used for CDT analysis was IEF-PAGE. Sera of 49 males and 11 females aged 14-87 years, average age 46.85 +/- 18.53, were used in this study. Control group consisted of five patients who died after medical treatment that lasted longer than 15 days, and five patients who started Disulfiram therapy in controlled hospital environment. Results The results obtained in CDT examination in dead bodies' sera showed sensitivity 59% and specificity 71%. A high incidence of falsely positive CDT result was noticed in liver failure and cirrhosis of non-alcoholic origin. CDT analysis is also possible to be done in samples collected postmortem up to 76 hours. Conclusion In forensic medicine, the method of CDT determination is reliable for the diagnosis of alcohol abuse.Uvod. Poslednjih godina transferin s nedostatkom ugljenih hidrata (engl. carbohydrate-deficient transferrin - CDT) jedan je od markera zloupotrebe alkohola koji je pokazao najbolje rezultate u sudskoj medicini. Cilj rada. Cilj studije je bio da se odredi korelacija između aktuelne metodologije dijagnoze zloupotrebe alkohola na postmortalnom materijalu (makroskopski i mikroskopski nalaz) i određivanja CDT korišćenjem metode isoelektrofokusiranja (engl. isoelectric focusing - IEF) u poliakrilamidnom gelu (engl. polyacrylamide gel electrophoresis - PAGE). Utvrđivano je da li interval između vremena smrti i uzimanja uzoraka za CDT analizu utiče na nalaz CDT. Metode rada. Za analizu CDT korišćena je metoda IEF-PAGE. Za studiju su analizirani serumi 49 muškaraca i 11 žena prosečne starosti od 46,85±18,53 godina (raspon 14-87 godina). Kontrolnu grupu činilo je pet pacijenata koji su umrli nakon bolničkog lečenja koje je trajalo duže od 15 dana i pet pacijenata kod kojih je u kontrolisanim bolničkim uslovima počelo lečenje disulfiramom. Rezultati. Dobijeni rezultati pokazuju da ova metoda analize CDT na postmortalnom materijalu ima senzitivnost od 59% i specifičnost od 71%. Visoka učestalost lažno pozitivnih rezultata utvrđena je kod oboljenja jetre i ci- roze nealkoholnog porekla. Analizu CDT je moguće raditi i iz uzoraka uzetih do 76 sati nakon smrti. Zaključak. U sudskomedicinskoj praksi ova metoda analize CDT može se koristiti za dijagnostikovanje hronične zloupotrebe alkohola

Design and Development of Calcium Sensitive Contrast Agents for fMRI

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2009.Cataloged from PDF version of thesis.Includes bibliographical references.There is a considerable interest in new technologies that allow noninvasive imaging of physiological parameters in living systems, especially in the neuroscience. Magnetic resonance imaging (MRI) is a very powerful tool for neuroimaging, because it can image the tissue noninvasively, in depth, at a good spatial (~100 pm) and temporal (~1s) resolution. In order to study neural activity at a cellular level, it would be of notable significance to combine MRI with calcium-sensitive contrast agents because of the important role of calcium as a second messenger in cellular signaling pathways. Here we describe a family of calcium sensors for MRI based on the conjugation of superparamagnetic iron oxide nanoparticles (SPIOS) to calcium sensing protein calmodulin and its target peptides. In the presence of calcium, interaction between the two protein domains drives the aggregation of SPIOs which results in up to four fold T2 changes. The calcium sensing is reversible and occurs at midpoint of roughly 1 ptM Ca , which makes these contrast agents suitable for imaging of the cytosolic calcium fluctuations in cells. We introduce two generations of these sensors: the first one based on commercial larger SPIOs, and the second one that uses small crosslinked lipid coated nanoparticles (xLCIOs) which have potential to overcome some of the limitations of the prototype sensor, such as inadequate diffusivity and relatively slow kinetic response. When combined with technologies for cellular deliveries of nanoparticles, these sensors and their derivatives may be useful for functional molecular imaging of biological signaling network in live, opaque specimens.by Tatjana Atanasijevic.Ph.D

Manganese displacement from Zinpyr-1 allows zinc detection by fluorescence microscopy and magnetic resonance imaging

A paramagnetic manganese complex of a fluorescein-based probe affords a dual-modality zinc sensor featuring an improved fluorescence dynamic range and an MRI readout.National Institute of General Medical Sciences (U.S.) ((Grant GM065519)SBS FoundationNational Institutes of Health (U.S.) (NIH Grant DP2-OD2441)Raymond and Beverley Sackler Foundatio

CHARACTERISTICS OF GETTING INJURED AND WOUNDED IN THE NATO AGGRESSION VICTIMS ON THE TERRITORY OF BELGRADE

During the NATO aggression against Yugoslavia in the period from March toJune, 1999, at the Institute for Forensic Medicine in Belgrade there were 34 victimsregistered, namely, 22 of male and 12 of male sex. The greatest number of the killedwas of younger age, namely, of 31 to 40 years of age (l O persons) and from 21 to 30years of age (8 persons) while three victims were children up to 10 years of age. Onlyin one čaše the person on duty was wounded while all the other victims were civilianswho got fatal injuries out of the military objects. The wounds were in most casesinflicted by the NATO aviation actions at night, from midnight to 6 o'clock a. m. (28).In the inner city zone 26 persons were hurt; 6 were hurt in the villages aroundBelgrade and two in the suburban settlements. Half of them were killed at their jobs;16 of them were killed in the building of the Radio Television of Serbia; 9 were killedin their homes; 3 were killed in the hospital just like in the embassy and 2 in the street.Most of the persons (33) got injured due to a direct mechanical and/or thermal effectof explosive weapons. The forensic-medical autopsy was done on 31 victims. In 30cases the death occurred at the place where in the injury was inflicted

Dynamic imaging with MRI contrast agents: quantitative considerations. Magn Reson Imaging 24

Abstract Time-resolved MRI has had enormous impact in cognitive science and may become a significant tool in basic biological research with the application of new molecular imaging agents. In this paper, we examine the temporal characteristics of MRI contrast agents that could be used in dynamic studies. We consider bsmartQ T1 contrast agents, T2 agents based on reversible aggregation of superparamagnetic nanoparticles and sensors that produce changes in saturation transfer effects (chemical exchange saturation transfer, CEST). We discuss response properties of several agents with reference to available experimental data, and we develop a new theoretical model that predicts the response rates and relaxivity changes of aggregation-based sensors. We also perform calculations to define the extent to which constraints on temporal resolution are imposed by the imaging methods themselves. Our analysis confirms that some small T1 agents may be compatible with MRI temporal resolution on the order of 100 ms. Nanoparticle aggregation T2 sensors are applicable at much lower concentrations, but are likely to respond on a single second or slower timescale. CEST agents work at high concentrations and temporal resolutions of 1-10 s, limited by a requirement for long presaturation periods in the MRI pulse sequence.

The value of the post mortem analysis of carboxyhemoglobin concentration in the blood: A 15-year study

Introduction/Objective The purpose of this retrospective study was to assess carboxyhemoglobin (HbCO) concentration in all autopsy cases of fire and non-fire victims - all those who have been suspected to be under the influence of carbon monoxide (CO) in the Belgrade area during a 15-year period (1990-2005). Methods Correlations between the concentration of HbCO, circumstances of death, vital signs, and prior health conditions, smoking and history of alcohol-abuse, have been particularly analyzed in 192 autopsy cases. Results The investigation included 52 (27%) females and 140 (73%) males, their average age being 50.78 years. CO poisoning has been established as the cause of death in 74 cases (38%). The manner of death in 170 cases (89%) was an accident, in eight (3%) suicide, in two (1%) murder, in 11 (6%) natural death, and in one case the manner of death hasn't been established. Such distribution of the manner of death differentiates this study from others of similar type, and it is conditioned by the specificity of life in this region. Conclusion The predictors of a high HbCO concentration are the sex, cause of death, manner of death, soot aspiration, lower-degree burns. According to the results, we profiled a typical victim of CO poisoning.Uvod/Cilj Cilj retrospektivne studije bio je određivanje koncentracije karboksihemoglobina (HbCO) u svim slučajevima žrtava iz požara i onih koji nisu u vezi sa njim, na području Beograda, u periodu 1990-2005, odnosno svih sluačajeva za koje se sumnjalo da su bili izloženi ugljen-monoksidu (SO). Metode U 192 slučaja obdukcije posebno su analizirane: korelacija između koncentracije HbCO, okolnosti umiranja, vitalnih reakcija, prethodnog zdravstvenog stanja, pušenja i zloupotrebe alkohola. Rezultati Ispitivanje je obuhvatilo 52 (27%) žene i 140 (73%) muškaraca prosečne starosti 50,78 godina. Trovanje SO je utvrđeno kao uzrok smrti u 74 slučaja (38%). U 170 slučajeva (89%) radilo se o zadesima, u 8 (3%) o samoubistvima, u 2 (1%) o ubistvima. U 11 slučajeva (6%) reč je bilo o prirodnoj smrti, dok u jednom slučaju uzrok smrti nije ustanovljen. Ovakva raspodela diferencira ovu studiju od sličnih i uslovljena je specifičnostima života u regionu. Zaključak Prediktori visoke koncentracije HbCO su pol, uzrok smrti, način smrti, aspiracija čađi, stepen izgorevanja. Na osnovu rezultata napravljen je profil žrtve trovanja SO