The DosiMap, a new 2D scintillating dosimeter for IMRT quality assurance: characterization of two Cerenkov discrimination methods.

PubMed

Frelin, A M; Fontbonne, J M; Ban, G; Colin, J; Labalme, M; Batalla, A; Vela, A; Boher, P; Braud, M; Leroux, T

2008-05-01

New radiation therapy techniques such as IMRT present significant efficiency due to their highly conformal dose distributions. A consequence of the complexity of their dose distributions (high gradients, small irradiation fields, low dose distribution, ...) is the requirement for better precision quality assurance than in classical radiotherapy in order to compare the conformation of the delivered dose with the planned dose distribution and to guarantee the quality of the treatment. Currently this control is mostly performed by matrices of ionization chambers, diode detectors, dosimetric films, portal imaging, or dosimetric gels. Another approach is scintillation dosimetry, which has been developed in the last 15 years mainly through scintillating fiber devices. Despite having many advantages over other methods it is still at an experimental level for routine dosimetry because the Cerenkov radiation produced under irradiation represents an important stem effect. A new 2D water equivalent scintillating dosimeter, the DosiMap, and two different Cerenkov discrimination methods were developed with the collaboration of the Laboratoire de Physique Corpusculaire of Caen, the Comprehensive Cancer Center François Baclesse, and the ELDIM Co., in the frame of the MAESTRO European project. The DosiMap consists of a plastic scintillating sheet placed inside a transparent polystyrene phantom. The light distribution produced under irradiation is recorded by a CCD camera. Our first Cerenkov discrimination technique is subtractive. It uses a chessboard pattern placed in front of the scintillator, which provides a background signal containing only Cerenkov light. Our second discrimination technique is colorimetric. It performs a spectral analysis of the light signal, which allows the unfolding of the Cerenkov radiation and the scintillation. Tests were carried out with our DosiMap prototype and the performances of the two discrimination methods were assessed. The comparison of the dose measurements performed with the DosiMap and with dosimetric films for three different irradiation configurations showed discrepancies smaller than 3.5% for a 2 mm spatial resolution. Two innovative discrimination solutions were demonstrated to separate the scintillation from the Cerenkov radiation. It was also shown that the DosiMap, which is water equivalent, fast, and user friendly, is a very promising tool for radiotherapy quality assurance.

Compatibility and competitiveness of a laboratory strain of Anastrepha Fraterculus (Diptera: Tephritidae) after irradiation treatment

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

Allinghi, A.; Calcagno, G.; Gomez Cendra, P.

We evaluated under semi-natural field cage conditions sexual compatibility and competitiveness of a laboratory strain (LAB) compared to a wild population (TUC) of Anastrepha fraterculus (Wiedemann). The LAB strain is produced under semi-mass rearing conditions at the Estacion Experimental Agroindustrial Obispo Colombres facility (Tucuman, Argentina). Wild flies were obtained at Horco Molle (Tucuman, Argentina) from infested guava fruits. LAB pupae were irradiated ({sup 60}Co) 48 h before adult emergence. The tested doses were 0 (control), 40, 70, and 100 Gy. Twenty-five males and 25 females each of TUC and LAB were released into cages and mating pairs collected. Only 1more » irradiation dose was considered at a time. Females were separated and allowed to lay eggs into artificial fruits to estimate induced sterility from the corresponding hatching rate. Copulation start time did not differ significantly between strains nor among irradiation treatments. Copulation duration showed highly significant differences among irradiation doses, but no differences between strains. The index of sexual isolation (ISI) and the relative sterility index (RSI) indices indicated that LAB and TUC are fully compatible, males from TUC and LAB did not differ in mating competitiveness, and irradiation within the range tested did not affect these indices. Non-irradiated LAB females exhibited higher mating propensity than TUC ones. However, a significant reduction in the female relative performance index (FRPI) index was observed with increasing irradiation dose. The analysis of induced sterility indicated that treatment with 40 Gy reduces male fertility from about 80% to 0.75%, and higher doses produce total sterility. In females, the 40 Gy dose reduces fertility to about 2% and higher doses prevent egg laying. (author) [Spanish] Se evaluo bajo condiciones semi-naturales en jaulas de campo la compatibilidad y la competitividad sexual de una linea de laboratorio (LAB) con respecto a una poblacion salvaje (TUC) de Anastrepha fraterculus (Wiedemann). La linea de laboratorio se produce en condiciones de cria semi-masiva en las instalaciones de la Estacion Experimental Agroindustrial Obispo Colombres (Tucuman, Argentina). Las moscas salvajes se obtuvieron de frutas infestadas de guayabos en Horco Molle (Tucuman, Argentina). Las pupas de laboratorio fueron irradiadas ({sup 60}Co) 48 horas antes de la emergencia del adulto. Las dosis utilizadas fueron 0 (control), 40, 70, y 100 Gy. Se liberaron 25 machos y 25 hembras de TUC y LAB dentro de las jaulas y se recolectaron las parejas formadas. Solo se considero 1 dosis de irradiacion por vez. Las hembras apareadas fueron separadas y se les permitio poner huevos en frutas artificiales para estimar la esterilidad inducida a traves del porcentaje de eclosion. La hora de inicio de la copula no difirio significativamente entre poblaciones ni entre los tratamientos de irradiacion. La duracion de la copula mostro grandes diferencias entre dosis de irradiacion pero no entre cepas. Los indices ISI (aislamiento) y el RSI (esterilidad relativa) indican que LAB y TUC son totalmente compatibles, los machos de TUC y LAB no difieren en su competitividad y la irradiacion dentro del rango de dosis utilizadas tampoco afecto este indice. Las hembras LAB no irradiadas muestran una mayor propension para el apareamiento que las hembras de TUC. Sin embargo se observo una reduccion significativa del indice FRPI (actuacion relativa de hembras) a medida que se aumenta la dosis de irradiacion. El analisis de la esterilidad inducida indica que con dosis de 40 Gy la fertilidad disminuye del 80% al 0.75%, y con dosis mayores la esterilidad fue total. Las hembras irradiadas con dosis de 40 Gy tienen una fertilidad de aproximadamente 2% y con dosis mayores no ponen huevos. (author)« less

Performance evaluation of integrated solid-liquid wastes treatment technology in palm oil industry

NASA Astrophysics Data System (ADS)

Amelia, J. R.; Suprihatin, S.; Indrasti, N. S.; Hasanudin, U.; Fujie, K.

2017-05-01

The oil palm industry significantly contributes to environmental degradation if without waste management properly. The newest alternative waste management that might be developed is by utilizing the effluent of POME anaerobic digestion with EFB through integrated anaerobic decomposition process. The aim of this research was to examine and evaluate the integrated solid-liquid waste treatment technology in the view point of greenhouse gasses emission, compost, and biogas production. POME was treated in anaerobic digester with loading rate about 1.65 gCOD/L/day. Treated POME with dosis of 15 and 20 L/day was sprayed to the anaerobic digester that was filled of 25 kg of EFB. The results of research showed that after 60 days, the C/N ratio of EFB decreased to 12.67 and 10.96 for dosis of treated POME 15 and 20 L/day, respectively. In case of 60 day decomposition, the integrated waste treatment technology could produce 51.01 and 34.34 m3/Ton FFB which was equivalent with 636,44 and 466,58 kgCO2e/ton FFB for dosis of treated POME 15 and 20 L/day, respectively. The results of research also showed that integrated solid-liquid wastes treatment technology could reduce GHG emission about 421.20 and 251.34 kgCO2e/ton FFB for dosis of treated POME 15 and 20 L/day, respectively.

Performance assessment of diffuse optical spectroscopic imaging instruments in a 2-year multicenter breast cancer trial

NASA Astrophysics Data System (ADS)

Leproux, Anaïs; O'Sullivan, Thomas D.; Cerussi, Albert; Durkin, Amanda; Hill, Brian; Hylton, Nola; Yodh, Arjun G.; Carp, Stefan A.; Boas, David; Jiang, Shudong; Paulsen, Keith D.; Pogue, Brian; Roblyer, Darren; Yang, Wei; Tromberg, Bruce J.

2017-12-01

We present a framework for characterizing the performance of an experimental imaging technology, diffuse optical spectroscopic imaging (DOSI), in a 2-year multicenter American College of Radiology Imaging Network (ACRIN) breast cancer study (ACRIN-6691). DOSI instruments combine broadband frequency-domain photon migration with time-independent near-infrared (650 to 1000 nm) spectroscopy to measure tissue absorption and reduced scattering spectra and tissue hemoglobin, water, and lipid composition. The goal of ACRIN-6691 was to test the effectiveness of optically derived imaging endpoints in predicting the final pathologic response of neoadjuvant chemotherapy (NAC). Sixty patients were enrolled over a 2-year period at participating sites and received multiple DOSI scans prior to and during 3- to 6-month NAC. The impact of three sources of error on accuracy and precision, including different operators, instruments, and calibration standards, was evaluated using a broadband reflectance standard and two different solid tissue-simulating optical phantoms. Instruments showed <0.0010 mm-1 (10.3%) and 0.06 mm-1 (4.7%) deviation in broadband absorption and reduced scattering, respectively, over the 2-year duration of ACRIN-6691. These variations establish a useful performance criterion for assessing instrument stability. The proposed procedures and tests are not limited to DOSI; rather, they are intended to provide methods to characterize performance of any instrument used in translational optical imaging.

[Critical test of the activity of tetramisole phosphate on gastrointestinal helminths of sheep].

PubMed

Oba, M S; Mello, E de B; Dell'Porto, A; Soares, M A; Schumaker, T T

1979-01-01

The phosphate sale of tetramizol assayed in naturally infested sheep by subcutaneous infection at the dosis of 8,66 mg/kg revealed very high efficiency against strongylid gastro-intestinal nematodes; its efficiency was comparable that found by several authors for the hydrochloride and cyclamate salts of the same drug, also by subcutaneious injection, at the dosis of 10 mg/kg. In what concerns helminths belonging to the genera Strongyloides and Capillaria our results were not conclusive enough.

Design of a rectal probe for diffuse optical spectroscopy imaging for chemotherapy and radiotherapy monitoring

NASA Astrophysics Data System (ADS)

van de Giessen, Martijn; Santoro, Ylenia; Mirzaei Zarandi, Soroush; Pigazzi, Alessio; Cerussi, Albert E.; Tromberg, Bruce J.

2014-03-01

Diffuse optical spectroscopy imaging (DOSI) has shown great potential for the early detection of non-responding tumors during neoadjuvant chemotherapy in breast cancer, already one day after therapy starts. Patients with rectal cancer receive similar chemotherapy treatment. The rectum geometry and tissue properties of healthy and tumor tissue in the rectum and the requirement of surface contact impose constraints on the probe design. In this work we present the design of a DOSI probe with the aim of early chemotherapy/radiotherapy effectiveness detection in rectal tumors. We show using Monte Carlo simulations and phantom measurements that the colon tissue can be characterized reliably using a source-detector separation in the order of 10 mm. We present a design and rapid prototype of a probe for DOSI measurements that can be mounted on a standard laparoscope and that fits through a standard rectoscope. Using predominantly clinically approved components we aim at fast clinical translation.

Differential diagnosis of breast masses in South Korean premenopausal women using diffuse optical spectroscopic imaging

NASA Astrophysics Data System (ADS)

Leproux, Anaïs; Kim, You Me; Min, Jun Won; McLaren, Christine E.; Chen, Wen-Pin; O'Sullivan, Thomas D.; Lee, Seung-ha; Chung, Phil-Sang; Tromberg, Bruce J.

2016-07-01

Young patients with dense breasts have a relatively low-positive biopsy rate for breast cancer (˜1 in 7). South Korean women have higher breast density than Westerners. We investigated the benefit of using a functional and metabolic imaging technique, diffuse optical spectroscopic imaging (DOSI), to help the standard of care imaging tools to distinguish benign from malignant lesions in premenopausal Korean women. DOSI uses near-infrared light to measure breast tissue composition by quantifying tissue concentrations of water (ctH2O), bulk lipid (ctLipid), deoxygenated (ctHHb), and oxygenated (ctHbO2) hemoglobin. DOSI spectral signatures specific to abnormal tissue and absent in healthy tissue were also used to form a malignancy index. This study included 19 premenopausal subjects (average age 41±9), corresponding to 11 benign and 10 malignant lesions. Elevated lesion to normal ratio of ctH2O, ctHHb, ctHbO2, total hemoglobin (THb=ctHHb+ctHbO2), and tissue optical index (ctHHb×ctH2O/ctLipid) were observed in the malignant lesions compared to the benign lesions (p<0.02). THb and malignancy index were the two best single predictors of malignancy, with >90% sensitivity and specificity. Malignant lesions showed significantly higher metabolism and perfusion than benign lesions. DOSI spectral features showed high discriminatory power for distinguishing malignant and benign lesions in dense breasts of the Korean population.

31P-edited diffusion-ordered 1H NMR spectroscopy for the spectral isolation and identification of organophosphorus compounds related to chemical weapons agents and their degradation products.

PubMed

Mayer, Brian P; Valdez, Carlos A; Hok, Saphon; Chinn, Sarah C; Hart, Bradley R

2012-12-04

Organophosphorus compounds represent a large class of molecules that include pesticides, flame-retardants, biologically relevant molecules, and chemical weapons agents (CWAs). The detection and identification of organophosphorus molecules, particularly in the cases of pesticides and CWAs, are paramount to the verification of international treaties by various organizations. To that end, novel analytical methodologies that can provide additional support to traditional analyses are important for unambiguous identification of these compounds. We have developed an NMR method that selectively edits for organophosphorus compounds via (31)P-(1)H heteronuclear single quantum correlation (HSQC) and provides an additional chromatographic-like separation based on self-diffusivities of the individual species via (1)H diffusion-ordered spectroscopy (DOSY): (1)H-(31)P HSQC-DOSY. The technique is first validated using the CWA VX (O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate) by traditional two-dimensional DOSY spectra. We then extend this technique to a complex mixture of VX degradation products and identify all the main phosphorus-containing byproducts generated after exposure to a zinc-cyclen organometallic homogeneous catalyst.

Analysis of ligand-protein exchange by Clustering of Ligand Diffusion Coefficient Pairs (CoLD-CoP)

NASA Astrophysics Data System (ADS)

Snyder, David A.; Chantova, Mihaela; Chaudhry, Saadia

2015-06-01

NMR spectroscopy is a powerful tool in describing protein structures and protein activity for pharmaceutical and biochemical development. This study describes a method to determine weak binding ligands in biological systems by using hierarchic diffusion coefficient clustering of multidimensional data obtained with a 400 MHz Bruker NMR. Comparison of DOSY spectrums of ligands of the chemical library in the presence and absence of target proteins show translational diffusion rates for small molecules upon interaction with macromolecules. For weak binders such as compounds found in fragment libraries, changes in diffusion rates upon macromolecular binding are on the order of the precision of DOSY diffusion measurements, and identifying such subtle shifts in diffusion requires careful statistical analysis. The "CoLD-CoP" (Clustering of Ligand Diffusion Coefficient Pairs) method presented here uses SAHN clustering to identify protein-binders in a chemical library or even a not fully characterized metabolite mixture. We will show how DOSY NMR and the "CoLD-CoP" method complement each other in identifying the most suitable candidates for lysozyme and wheat germ acid phosphatase.

Hemodynamic analysis of patients in intensive care unit based on diffuse optical spectroscopic imaging system

NASA Astrophysics Data System (ADS)

Hsieh, Yao-Sheng; Wang, Chun-Yang; Ling, Yo-Wei; Chuang, Ming-Lung; Chuang, Ching-Cheng; Tsai, Jui-che; Lu, Chih-Wei; Sun, Chia-Wei

2010-02-01

Diffuse optical spectroscopic imaging (DOSI) is a technique to assess the spatial variation in absorption and scattering properties of the biological tissues and provides the monitoring of changes in concentrations of oxy-hemoglobin and deoxy-hemoglobin. In our preliminary study, the temporal tracings of hemodynamic oxygenation are measured with DOSI and venous occlusion test (VOT) from normal subjects, patients with heart failure and patients with sepsis in intensive care unit (ICU). In experiments, the obvious differences of hemodynamic signals can be observed among the three groups. The physiological relevance of VOT hemodynamics with respect to diseases is also discussed in this paper.

Application of diffusion ordered-1H-nuclear magnetic resonance spectroscopy to quantify sucrose in beverages.

PubMed

Cao, Ruge; Nonaka, Airi; Komura, Fusae; Matsui, Toshiro

2015-03-15

This work focuses on a quantitative analysis of sucrose using diffusion ordered-quantitative (1)H-nuclear magnetic resonance spectroscopy (DOSY-qNMR), where an analyte can be isolated from interference based on its characteristic diffusion coefficient (D) in gradient magnetic fields. The D value of sucrose in deuterium oxide at 30°C was 4.9 × 10(-10)m(2)/s at field gradient pulse from 5.0 × 10(-2) to 3.0 × 10(-1)T/m, separated from other carbohydrates (glucose and fructose). Good linearity (r(2)=0.9999) was obtained between sucrose (0.5-20.0 g/L) and the resonance area of target glucopyranosyl-α-C1 proton normalised to that of cellobiose C1 proton (100.0 g/L, as an internal standard) in 1D sliced DOSY spectrum. The DOSY-qNMR method was successfully applied to quantify sucrose in orange juice (36.1 ± 0.5 g/L), pineapple juice (53.5 ± 1.1g/L) and a sports drink (24.7 ± 0.6g/L), in good agreement with the results obtained by an F-kit method. Copyright © 2014 Elsevier Ltd. All rights reserved.

Analysis of ligand-protein exchange by Clustering of Ligand Diffusion Coefficient Pairs (CoLD-CoP).

PubMed

Snyder, David A; Chantova, Mihaela; Chaudhry, Saadia

2015-06-01

NMR spectroscopy is a powerful tool in describing protein structures and protein activity for pharmaceutical and biochemical development. This study describes a method to determine weak binding ligands in biological systems by using hierarchic diffusion coefficient clustering of multidimensional data obtained with a 400 MHz Bruker NMR. Comparison of DOSY spectrums of ligands of the chemical library in the presence and absence of target proteins show translational diffusion rates for small molecules upon interaction with macromolecules. For weak binders such as compounds found in fragment libraries, changes in diffusion rates upon macromolecular binding are on the order of the precision of DOSY diffusion measurements, and identifying such subtle shifts in diffusion requires careful statistical analysis. The "CoLD-CoP" (Clustering of Ligand Diffusion Coefficient Pairs) method presented here uses SAHN clustering to identify protein-binders in a chemical library or even a not fully characterized metabolite mixture. We will show how DOSY NMR and the "CoLD-CoP" method complement each other in identifying the most suitable candidates for lysozyme and wheat germ acid phosphatase. Copyright © 2015 Elsevier Inc. All rights reserved.

Longitudinal optical monitoring of blood flow in breast tumors during neoadjuvant chemotherapy

NASA Astrophysics Data System (ADS)

Cochran, J. M.; Chung, S. H.; Leproux, A.; Baker, W. B.; Busch, D. R.; DeMichele, A. M.; Tchou, J.; Tromberg, B. J.; Yodh, A. G.

2017-06-01

We measure tissue blood flow markers in breast tumors during neoadjuvant chemotherapy and investigate their correlation to pathologic complete response in a pilot longitudinal patient study (n  =  4). Tumor blood flow is quantified optically by diffuse correlation spectroscopy (DCS), and tissue optical properties, blood oxygen saturation, and total hemoglobin concentration are derived from concurrent diffuse optical spectroscopic imaging (DOSI). The study represents the first longitudinal DCS measurement of neoadjuvant chemotherapy in humans over the entire course of treatment; it therefore offers a first correlation between DCS flow indices and pathologic complete response. The use of absolute optical properties measured by DOSI facilitates significant improvement of DCS blood flow calculation, which typically assumes optical properties based on literature values. Additionally, the combination of the DCS blood flow index and the tissue oxygen saturation from DOSI permits investigation of tissue oxygen metabolism. Pilot results from four patients suggest that lower blood flow in the lesion-bearing breast is correlated with pathologic complete response. Both absolute lesion blood flow and lesion flow relative to the contralateral breast exhibit potential for characterization of pathological response. This initial demonstration of the combined optical approach for chemotherapy monitoring provides incentive for more comprehensive studies in the future and can help power those investigations.

DOSIS & DOSIS 3D: radiation measurements with the DOSTEL instruments onboard the Columbus Laboratory of the ISS in the years 2009-2016

NASA Astrophysics Data System (ADS)

Berger, Thomas; Burmeister, Sönke; Matthiä, Daniel; Przybyla, Bartos; Reitz, Günther; Bilski, Pawel; Hajek, Michael; Sihver, Lembit; Szabo, Julianna; Ambrozova, Iva; Vanhavere, Filip; Gaza, Ramona; Semones, Edward; Yukihara, Eduardo G.; Benton, Eric R.; Uchihori, Yukio; Kodaira, Satoshi; Kitamura, Hisashi; Boehme, Matthias

2017-03-01

The natural radiation environment in Low Earth Orbit (LEO) differs significantly in composition and energy from that found on Earth. The space radiation field consists of high energetic protons and heavier ions from Galactic Cosmic Radiation (GCR), as well as of protons and electrons trapped in the Earth's radiation belts (Van Allen belts). Protons and some heavier particles ejected in occasional Solar Particle Events (SPEs) might in addition contribute to the radiation exposure in LEO. All sources of radiation are modulated by the solar cycle. During solar maximum conditions SPEs occur more frequently with higher particle intensities. Since the radiation exposure in LEO exceeds exposure limits for radiation workers on Earth, the radiation exposure in space has been recognized as a main health concern for humans in space missions from the beginning of the space age on. Monitoring of the radiation environment is therefore an inevitable task in human spaceflight. Since mission profiles are always different and each spacecraft provides different shielding distributions, modifying the radiation environment measurements needs to be done for each mission. The experiments "Dose Distribution within the ISS (DOSIS)" (2009-2011) and "Dose Distribution within the ISS 3D (DOSIS 3D)" (2012-onwards) onboard the Columbus Laboratory of the International Space Station (ISS) use a detector suite consisting of two silicon detector telescopes (DOSimetry TELescope = DOSTEL) and passive radiation detector packages (PDP) and are designed for the determination of the temporal and spatial variation of the radiation environment. With the DOSTEL instruments' changes of the radiation composition and the related exposure levels in dependence of the solar cycle, the altitude of the ISS and the influence of attitude changes of the ISS during Space Shuttle dockings inside the Columbus Laboratory have been monitored. The absorbed doses measured at the end of May 2016 reached up to 286 μGy/day with dose equivalent values of 647 μSv/day.

The DOSIS -Experiment onboard the Columbus Laboratory of the International Space Station -Overview and first mission results

NASA Astrophysics Data System (ADS)

Reitz, Guenther; Berger, Thomas; Kürner, Christine; Burmeister, Sünke; Hajek, Michael; Bilski, Pawel; Horwacik, Tomasz; Vanhavere, Filip; Spurny, Frantisek; Jadrnickova, Iva; Pálfalvi, József K.; O'Sullivan, Denis; Yasuda, Nakahiro; Uchihori, Yukio; Kitamura, Hisashi; Kodaira, Satoshi; Yukihara, Eduardo; Benton, Eric; Zapp, Neal; Gaza, Ramona; Zhou, Dazhuang; Semones, Edward; Roed, Yvonne; Boehme, Matthias; Haumann, Lutz

Besides the effects of the microgravity environment, and the psychological and psychosocial problems encountered in confined spaces, radiation is the main health detriment for long dura-tion human space missions. The radiation environment encountered in space differs in nature from that on earth, consisting mostly of high energetic ions from protons up to iron, resulting in radiation levels far exceeding the ones encountered on earth for occupational radiation workers. Accurate knowledge of the physical characteristics of the space radiation field in dependence on the solar activity, the orbital parameters and the different shielding configurations of the International Space Station ISS is therefore needed. The DOSIS (Dose Distribution inside the ISS) experiment, under the project and science lead of DLR, aims for the spatial and tempo-ral measurement of the radiation field parameters inside the European Columbus laboratory onboard the International Space Station. This goal is achieved by applying a combination of passive (Thermo-and Optical luminescence detectors and Nuclear track etch detectors) and active (silicon telescope) radiation detectors. The passive radiation detectors -so called pas-sive detector packages (PDP) are mounted at eleven positions within the Columbus laboratory -aiming for a spatial dose distribution measurement of the absorbed dose, the linear energy transfer spectra and the dose equivalent with an average exposure time of six months. Two active silicon telescopes -so called Dosimetry Telescopes (DOSTEL 1 and DOSTEL 2) together with a Data and Power Unit (DDPU) are mounted within the DOSIS Main Box at a fixed loca-tion beneath the European Physiology Module (EPM) rack. The DOSTEL 1 and DOSTEL 2 detectors are positioned at a 90 angle to each other for a precise measurement of the temporal and spatial variation of the radiation field, especially during crossing of the South Atlantic Anomaly (SAA). The DOSIS hardware was launched with the Space Shuttle Endeavour to the International Space Station on 15 July 2009 and installed by European Astronaut Frank de Winne on 18 July 2009. The first PDP set was downloaded after an exposure time of 124 days in November 2009 and a second PDP set was installed in November 2009. The active part of the instrument suit is working since July 2009. The presentation will give an overview about the DOSIS experiment as well as first results from the passive and active radiation detector measurements. The Austrian activities within this experiment were supported by the Austrian Space Appli-cations Programme (ASAP) of the Federal Ministry for Transport, Innovation and Technology under contract no. 819643. The Polish contribution to this work was supported by the Min-istry of Science and Higher Education, grant No. DWM/N118/ESA/2008. The Hungarian contribution was supported by the ESA PECS grant No. C98066.

Quality control and assurance for validation of DOS/I measurements

NASA Astrophysics Data System (ADS)

Cerussi, Albert; Durkin, Amanda; Kwong, Richard; Quang, Timothy; Hill, Brian; Tromberg, Bruce J.; MacKinnon, Nick; Mantulin, William W.

2010-02-01

Ongoing multi-center clinical trials are crucial for Biophotonics to gain acceptance in medical imaging. In these trials, quality control (QC) and assurance (QA) are key to success and provide "data insurance". Quality control and assurance deal with standardization, validation, and compliance of procedures, materials and instrumentation. Specifically, QC/QA involves systematic assessment of testing materials, instrumentation performance, standard operating procedures, data logging, analysis, and reporting. QC and QA are important for FDA accreditation and acceptance by the clinical community. Our Biophotonics research in the Network for Translational Research in Optical Imaging (NTROI) program for breast cancer characterization focuses on QA/QC issues primarily related to the broadband Diffuse Optical Spectroscopy and Imaging (DOS/I) instrumentation, because this is an emerging technology with limited standardized QC/QA in place. In the multi-center trial environment, we implement QA/QC procedures: 1. Standardize and validate calibration standards and procedures. (DOS/I technology requires both frequency domain and spectral calibration procedures using tissue simulating phantoms and reflectance standards, respectively.) 2. Standardize and validate data acquisition, processing and visualization (optimize instrument software-EZDOS; centralize data processing) 3. Monitor, catalog and maintain instrument performance (document performance; modularize maintenance; integrate new technology) 4. Standardize and coordinate trial data entry (from individual sites) into centralized database 5. Monitor, audit and communicate all research procedures (database, teleconferences, training sessions) between participants ensuring "calibration". This manuscript describes our ongoing efforts, successes and challenges implementing these strategies.

Kombinierte Hoch-/Niedrig-Dosis-Therapie mit systemischen Glukokor-tikoiden bei schweren Verlaufsformen der Alopecia areata im Kindesalter.

PubMed

Jahn-Bassler, Karin; Bauer, Wolfgang Michael; Karlhofer, Franz; Vossen, Matthias G; Stingl, Georg

2017-01-01

Schwere Verlaufsformen der Alopecia areata (AA) im Kindesalter sind aufgrund limitierter Optionen therapeutisch herausfordernd. Systemische, hochdosierte Glukokortikoide weisen die schnellste Ansprechrate auf, nach dem Absetzen kommt es allerdings zu Rezidiven. Eine längerfristige Hochdosis-Anwendung ist aufgrund der zu erwartenden Nebenwirkungen nicht empfehlenswert. Eine dauerhafte Steroiderhaltungstherapie unterhalb der Cushing-Schwellen-Dosis nach Bolustherapie könnte die Krankheitsaktivität ohne Nebenwirkungen längerfristig unterdrücken. Im Rahmen einer offenen Anwendungsbeobachtung wurden 13 Kinder mit schweren Formen der AA in diese Studie eingeschlossen. Bei sieben Kindern lag eine AA totalis/universalis vor, bei sechs eine multifokale AA mit Befall von mehr als 50 % der Kopfhaut. Das Therapieregime sah eine initiale Prednisolon-Dosierung von 2 mg/kg Körpergeweicht (KG) vor und wurde innerhalb von neun Wochen auf eine Erhaltungsdosierung unter der individuellen Cushing-Schwelle reduziert. Der Nachbeobachtungszeitraum betrug ein bis drei Jahre. Wir beobachteten in 62 % aller Fälle ein komplettes Nachwachsen der Haare. Die mittlere Dauer bis zum Ansprechen lag bei 6,6 Wochen und konnte mit der Erhaltungstherapie über den gesamten Beobachtungszeitraum aufrechterhalten werden. An Nebenwirkungen wurden ausschließlich eine Gewichtszunahme (1-3 kg) bei allen Behandelten sowie eine milde Steroidakne in 23 % der Fälle beobachtet. Die kombinierte Hoch-/Niedrig-Dosis-Therapie mit systemischen Glukokortikoiden mittels Prednisolon zeigte eine hohe, dauerhafte Ansprechrate ohne signifikante Nebenwirkungen. © 2017 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Novel method for the determination of average molecular weight of natural polymers based on 2D DOSY NMR and chemometrics: Example of heparin.

PubMed

Monakhova, Yulia B; Diehl, Bernd W K; Do, Tung X; Schulze, Margit; Witzleben, Steffen

2018-02-05

Apart from the characterization of impurities, the full characterization of heparin and low molecular weight heparin (LMWH) also requires the determination of average molecular weight, which is closely related to the pharmaceutical properties of anticoagulant drugs. To determine average molecular weight of these animal-derived polymer products, partial least squares regression (PLS) was utilized for modelling of diffused-ordered spectroscopy NMR data (DOSY) of a representative set of heparin (n=32) and LMWH (n=30) samples. The same sets of samples were measured by gel permeation chromatography (GPC) to obtain reference data. The application of PLS to the data led to calibration models with root mean square error of prediction of 498Da and 179Da for heparin and LMWH, respectively. The average coefficients of variation (CVs) did not exceed 2.1% excluding sample preparation (by successive measuring one solution, n=5) and 2.5% including sample preparation (by preparing and analyzing separate samples, n=5). An advantage of the method is that the sample after standard 1D NMR characterization can be used for the molecular weight determination without further manipulation. The accuracy of multivariate models is better than the previous results for other matrices employing internal standards. Therefore, DOSY experiment is recommended to be employed for the calculation of molecular weight of heparin products as a complementary measurement to standard 1D NMR quality control. The method can be easily transferred to other matrices as well. Copyright © 2017 Elsevier B.V. All rights reserved.

Induction of sterility in Anastrepha Fraterculus (Diptera: Tephritidae) by gamma radiation

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

Allinghi, A.; Gramajo, C.; Willink, E.

In relation to the application of the sterile insect technique (SIT) for the South American fruit fly Anastrepha fraterculus (Wiedemann), we analyzed the effect on adult fertility of different doses of gamma irradiation and the age of pupae at the time of irradiation. In a first experiment, we applied doses of 50, 70, and 90 Gy to pupae at 24, 48, 72, and 96 h before adult emergence. In a second experiment we irradiated pupae 48 h before emergence with 20, 40, and 60 Gy and estimated male and female fertility and sperm transfer by irradiated males. The results indicatedmore » pupal age at irradiation does not significantly affect male fertility. If males irradiated with 60 Gy are crossed to non-irradiated females the fertility is about 1%. Females irradiated with 40 Gy did not lay eggs independently of the male to which they mated. No significant effects of radiation were observed with respect to the ability of males to transfer sperm. A dose of 70 Gy applied 48 h before adult emergence induces 100% sterility in both males and females. (author) [Spanish] Para la aplicacion de la tecnica del insecto esteril (TIE) en Anastrepha fraterculus (Wiedemann), en este trabajo analizamos el efecto de diferentes dosis de irradiacion gamma y la edad optima de la pupa al momento de la irradiacion. En el primer experimento se evaluaron las dosis de 50, 70, y 90 Gy en pupas de 24, 48, 72, y 96 h antes de la emergencia del adulto. En el segundo experimento se irradiaron pupas 48 h antes de la emergencia con dosis de 20, 40, 60 Gy y se estimo la fertilidad de los machos y las hembras, y la transferencia de espermas por los machos irradiados. Los resultados indicaron que la irradiacion no modifico significativamente la fertilidad de los machos. En las cruzas de machos irradiados a 60 Gy con hembras no irradiadas se observo 1% de eclosion larvaria, mientras que las hembras irradiadas a 40 Gy no pusieron huevos. La irradiacion no afecto significativamente la transferencia de espermas de los machos tratados. Por lo tanto, una dosis de 70 Gy aplicada 48 h antes de la emergencia del adulto induce 100% de esterilidad tanto en machos como en hembras. (a0011uth.« less

The DOSIS -Experiment onboard the Columbus Laboratory of the International Space Station -First Mission Results from the Active DOSTEL Instruments

NASA Astrophysics Data System (ADS)

Burmeister, Soenke; Berger, Thomas; Beaujean, Rudolf; Boehme, Matthias; Haumann, Lutz; Kortmann, Onno; Labrenz, Johannes; Reitz, Guenther

Besides the effects of the microgravity environment, and the psychological and psychosocial problems encountered in confined spaces, radiation is the main health detriment for long dura-tion human space missions. The radiation environment encountered in space differs in nature from that on earth, consisting mostly of high energetic ions from protons up to iron, resulting in radiation levels far exceeding the ones encountered on earth for occupational radiation workers. Accurate knowledge of the physical characteristics of the space radiation field in dependence on the solar activity, the orbital parameters and the different shielding configurations of the International Space Station ISS is therefore needed. For the investigation of the spatial and temporal distribution of the radiation field inside the European COLUMBUS module the DLR experiment DOSIS (Dose Distribution Inside the ISS) was launched on July 15th 2009 with STS-127 to the ISS. The experimental package was transferred from the Space Shuttle into COLUMBUS on July 18th. It consists in a first part of a combination of passive detector packages (PDP) distributed at 11 locations inside the European Columbus Laboratory. The second part are two active radiation detectors (DOSTELs) with a DDPU (DOSIS Data and Power Unit) in a nomex pouch (DOSIS MAIN BOX) mounted at a fixed location beneath the European Physiology Module (EPM) inside COLUMBUS. After the successful installation the active part has been activated on the 18th July 2009. Each of the DOSTEL units consists of two 6.93 cm PIPS silicon detectors forming a telescope with an opening angle of 120. The two DOSTELs are mounted with their telescope axis perpendicular to each other to investigate anisotropies of the radiation field inside the COLUMBUS module especially during the passes through the South Atlantic Anomaly (SAA) and during Solar Particle Events (SPEs). The data from the DOSTEL units are transferred to ground via the EPM rack which is activated approximately every four weeks for this action. The first data downlink was performed on July 31st 2009. First Results for the DOSTEL measurements such as count rate profiles, dose rates and LET spectra will be presented in comparison to the data obtained by other experiments.

Characterization of water molecular state in in-vivo thick tissues using diffuse optical spectroscopic imaging

NASA Astrophysics Data System (ADS)

Chung, So Hyun

Structural changes in water molecules are related to physiological, anatomical and pathological properties of tissues. Near infrared (NIR) optical absorption methods are sensitive to water; however, detailed characterization of water in thick tissues is difficult to achieve because subtle spectral shifts can be obscured by multiple light scattering. In the NIR, a water absorption peak is observed around 975 nm. The precise NIR peak's shape and position are highly sensitive to water molecular disposition. A bound water index (BWI) was developed that quantifies the spectral shift and shape changes observed in tissue water absorption spectra measured by broadband diffuse optical spectroscopic imaging (DOSI). DOSI quantitatively measures light absorption and scattering spectra in cm-deep tissues and therefore reveals bound water spectral shifts. BWI as a water state index was validated by comparing broadband DOSI to MRI and a conductivity cell using bound water phantoms. Non-invasive BWI measurements of malignant and normal tissues in 18 subjects showed a significantly higher fraction of free water in malignant tissues (p<0.0001) compared to normal tissues. BWI showed potential as a prognostic index based on high correlations with tumor grade and size. An algorithm for absolute temperature measurements in deep tissues was developed based on resolving opposing effects of water vibrational frequency shifts due to macromolecular binding. DOSI measures absolute temperature with a difference of 1.1+/-0.91°C from a thermistor. Deep tissue temperature measured in forearms during cold-stress was consistent with previously reported invasively-measured deep tissue temperature. Finally, the BWI was compared to Apparent Diffusion Coefficient (ADC) of diffusion weighted MRI in 9 breast cancer patients. The BWI and ADC correlated (R=0.8, p=<0.01) and both parameters decreased with increasing bulk water content in cancer tissues. Although BWI and ADC are positively correlated in vivo, BWI appears to be more sensitive to free water in the extracellular matrix while ADC reflects increased tumor cellularity. The relationship between ADC, BWI and bulk water concentration suggests that both parameters have potential for assessing tumor histopathological grade. My results confirm the importance of water as a critical tissue component that can potentially provide unique insight into the molecular pathophysiology of cancer.

Probing the inner space of salt-bridged calix[5]arene capsules.

PubMed

Brancatelli, Giovanna; Gattuso, Giuseppe; Geremia, Silvano; Notti, Anna; Pappalardo, Sebastiano; Parisi, Melchiorre F; Pisagatti, Ilenia

2014-05-02

A combined DOSY and XRD study indicates that a carboxylcalix[5]arene receptor is able to encapsulate α,ω-diamines of appropriate length by means of a proton-transfer-mediated recognition process followed by salt-bridge-assisted bis-endo-complexation.

Combining Two-Dimensional Diffusion-Ordered Nuclear Magnetic Resonance Spectroscopy, Imaging Desorption Electrospray Ionization Mass Spectrometry, and Direct Analysis in Real-Time Mass Spectrometry for the Integral Investigation of Counterfeit Pharmaceuticals

PubMed Central

Nyadong, Leonard; Harris, Glenn A.; Balayssac, Stéphane; Galhena, Asiri S.; Malet-Martino, Myriam; Martino, Robert; Parry, R. Mitchell; Wang, May Dongmei; Fernández, Facundo M.; Gilard, Véronique

2016-01-01

During the past decade, there has been a marked increase in the number of reported cases involving counterfeit medicines in developing and developed countries. Particularly, artesunate-based antimalarial drugs have been targeted, because of their high demand and cost. Counterfeit antimalarials can cause death and can contribute to the growing problem of drug resistance, particularly in southeast Asia. In this study, the complementarity of two-dimensional diffusion-ordered 1H nuclear magnetic resonance spectroscopy (2D DOSY 1H NMR) with direct analysis in real-time mass spectrometry (DART MS) and desorption electrospray ionization mass spectrometry (DESI MS) was assessed for pharmaceutical forensic purposes. Fourteen different artesunate tablets, representative of what can be purchased from informal sources in southeast Asia, were investigated with these techniques. The expected active pharmaceutical ingredient was detected in only five formulations via both nuclear magnetic resonance (NMR) and mass spectrometry (MS) methods. Common organic excipients such as sucrose, lactose, stearate, dextrin, and starch were also detected. The graphical representation of DOSY 1H NMR results proved very useful for establishing similarities among groups of samples, enabling counterfeit drug “chemotyping”. In addition to bulk- and surface-average analyses, spatially resolved information on the surface composition of counterfeit and genuine antimalarial formulations was obtained using DESI MS that was performed in the imaging mode, which enabled one to visualize the homogeneity of both genuine and counterfeit drug samples. Overall, this study suggests that 2D DOSY 1H NMR, combined with ambient MS, comprises a powerful suite of instrumental analysis methodologies for the integral characterization of counterfeit antimalarials. PMID:19453162

Combining two-dimensional diffusion-ordered nuclear magnetic resonance spectroscopy, imaging desorption electrospray ionization mass spectrometry, and direct analysis in real-time mass spectrometry for the integral investigation of counterfeit pharmaceuticals.

PubMed

Nyadong, Leonard; Harris, Glenn A; Balayssac, Stéphane; Galhena, Asiri S; Malet-Martino, Myriam; Martino, Robert; Parry, R Mitchell; Wang, May Dongmei; Fernández, Facundo M; Gilard, Véronique

2009-06-15

During the past decade, there has been a marked increase in the number of reported cases involving counterfeit medicines in developing and developed countries. Particularly, artesunate-based antimalarial drugs have been targeted, because of their high demand and cost. Counterfeit antimalarials can cause death and can contribute to the growing problem of drug resistance, particularly in southeast Asia. In this study, the complementarity of two-dimensional diffusion-ordered (1)H nuclear magnetic resonance spectroscopy (2D DOSY (1)H NMR) with direct analysis in real-time mass spectrometry (DART MS) and desorption electrospray ionization mass spectrometry (DESI MS) was assessed for pharmaceutical forensic purposes. Fourteen different artesunate tablets, representative of what can be purchased from informal sources in southeast Asia, were investigated with these techniques. The expected active pharmaceutical ingredient was detected in only five formulations via both nuclear magnetic resonance (NMR) and mass spectrometry (MS) methods. Common organic excipients such as sucrose, lactose, stearate, dextrin, and starch were also detected. The graphical representation of DOSY (1)H NMR results proved very useful for establishing similarities among groups of samples, enabling counterfeit drug "chemotyping". In addition to bulk- and surface-average analyses, spatially resolved information on the surface composition of counterfeit and genuine antimalarial formulations was obtained using DESI MS that was performed in the imaging mode, which enabled one to visualize the homogeneity of both genuine and counterfeit drug samples. Overall, this study suggests that 2D DOSY (1)H NMR, combined with ambient MS, comprises a powerful suite of instrumental analysis methodologies for the integral characterization of counterfeit antimalarials.

Measurement of Solution Viscosity via Diffusion-Ordered NMR Spectroscopy (DOSY)

ERIC Educational Resources Information Center

Li, Weibin; Kagan, Gerald; Hopson, Russell; Williard, Paul G.

2011-01-01

Increasingly, the undergraduate chemistry curriculum includes nuclear magnetic resonance (NMR) spectroscopy. Advanced NMR techniques are often taught including two-dimensional gradient-based experiments. An investigation of intermolecular forces including viscosity, by a variety of methods, is often integrated in the undergraduate physical and…

The GNAT: A new tool for processing NMR data.

PubMed

Castañar, Laura; Poggetto, Guilherme Dal; Colbourne, Adam A; Morris, Gareth A; Nilsson, Mathias

2018-06-01

The GNAT (General NMR Analysis Toolbox) is a free and open-source software package for processing, visualising, and analysing NMR data. It supersedes the popular DOSY Toolbox, which has a narrower focus on diffusion NMR. Data import of most common formats from the major NMR platforms is supported, as well as a GNAT generic format. Key basic processing of NMR data (e.g., Fourier transformation, baseline correction, and phasing) is catered for within the program, as well as more advanced techniques (e.g., reference deconvolution and pure shift FID reconstruction). Analysis tools include DOSY and SCORE for diffusion data, ROSY T 1 /T 2 estimation for relaxation data, and PARAFAC for multilinear analysis. The GNAT is written for the MATLAB® language and comes with a user-friendly graphical user interface. The standard version is intended to run with a MATLAB installation, but completely free-standing compiled versions for Windows, Mac, and Linux are also freely available. © 2018 The Authors Magnetic Resonance in Chemistry Published by John Wiley & Sons Ltd.

Heteroleptic metallosupramolecular racks, rectangles, and trigonal prisms: stoichiometry-controlled reversible interconversion.

PubMed

Neogi, Subhadip; Lorenz, Yvonne; Engeser, Marianne; Samanta, Debabrata; Schmittel, Michael

2013-06-17

A simple approach toward preparation of heteroleptic two-dimensional (2D) rectangles and three-dimensional (3D) triangular prisms is described utilizing the HETPYP (HETeroleptic PYridyl and Phenanthroline metal complexes) concept. By mixing metal-loaded linear bisphenanthrolines of varying lengths with diverse (multi)pyridine (py) ligands in a proper ratio, six different self-assembled architectures arise cleanly and spontaneously in the absence of any template. They are characterized by (1)H and DOSY NMR, ESI-FT-ICR mass spectrometry as well as by Job plots and UV-vis titrations. Density functional theory (DFT) computations provide information about each structure. A stoichiometry-controlled supramolecule-to-supramolecule interconversion based on the relative amounts of metal bisphenanthroline and bipyridine forces the rectangular assembly to reorganize to a rack architecture and back to the rectangle, as clearly supported by variable temperature and DOSY NMR as well as dynamic light scattering data. The highly dynamic nature of the assemblies represents a promising starting point for constitutional dynamic materials.

Use of diffusion-ordered NMR spectroscopy and HPLC-UV-SPE-NMR to identify undeclared synthetic drugs in medicines illegally sold as phytotherapies.

PubMed

Silva, Lorena M A; Filho, Elenilson G A; Thomasi, Sérgio S; Silva, Bianca F; Ferreira, Antonio G; Venâncio, Tiago

2013-09-01

The informal (and/or illegal) e-commerce of pharmaceutical formulations causes problems that governmental health agencies find hard to control, one of which concerns formulas sold as natural products. The purpose of this work was to explore the advantages and limitations of DOSY and HPLC-UV-SPE-NMR. These techniques were used to identify the components of a formula illegally marketed in Brazil as an herbal medicine possessing anti-inflammatory and analgesic properties. DOSY was able to detect the major components present at higher concentrations. Complete characterization was achieved using HPLC-UV-SPE-NMR, and 1D and 2D NMR analyses enabled the identification of known synthetic drugs. These were ranitidine and a mixture of orphenadrine citrate, piroxicam, and dexamethasone, which are co-formulated in a remedy called Rheumazim that is used to relieve severe pain, but it is prohibited in Brazil because of a lack of sufficient pharmacokinetic and pharmacodynamic information. Copyright © 2013 John Wiley & Sons, Ltd.

Seguridad del paciente en Radioterapia Intraoperatoria: Impacto de los elementos controlados por el Radiofisico

NASA Astrophysics Data System (ADS)

Tarjuelo, Juan Lopez

Introduccion: En la administracion de la radioterapia intervienen profesionales y equipos de tratamiento, por lo que existe el riesgo de error y se precisa que dicho equipamiento funcione conforme a lo esperado. A los radiofisicos les corresponde participar en las actividades de garantia o aseguramiento de la calidad, incluyendo el control de calidad de los equipos, y en la evaluacion de los riesgos asociados. La radioterapia intraoperatoria (RIO) es una tecnica radioterapica de intensificacion de dosis, altamente selectiva, dirigida a volumenes anatomicos restringidos durante el tratamiento quirurgico oncologico, basada en la administracion de una dosis absorbida alta por medio de un haz de electrones tras el examen visual directo del lecho tumoral. Como incorporar los ultimos avances en el refuerzo de la seguridad en radioterapia es una tarea ambiciosa y compleja, resulta mas concreta y de inmediata aplicacion su introduccion en la RIO. El objetivo es analizar los elementos que reducen los riesgos y aumentan la seguridad en la RIO y su dosimetria, y valorar la funcion del radiofisico en esta labor. Material y metodos: Se emplearon el planificador Radiance de GMV y el acelerador lineal de los tratamientos de RIO Elekta Precise, controlado con el verificador diario de haces Daily QA Check 1090 y medido con las camaras de ionizacion PPC 40, FC65-G y FC65-P de PTW-Freiburg, a su vez verificadas con fuentes radiactivas adecuadas de estroncio-90 modelos CDP y CDC de IBA Dosimetry. Se realizo un analisis de modos de fallo y efectos (failure mode and effect analysis, FMEA) con el fin de identificar los elementos que forman la RIO y aplicar las herramientas necesarias para la minimizacion de los riesgos y la mejora de la seguridad en la tecnica. Se estudiaron las verificaciones diarias de dicho acelerador Precise con el control estadistico de procesos (statistical process control, SPC) y se simularon intervenciones para devolverlo al estado llamado en control. El SPC tambien se uso para estudiar la estabilidad de las camaras de ionizacion mencionadas. Se realizo la dosimetria in vivo en 45 pacientes con MOSFET reforzados mobile TN-502RDM-H, pelicula radiocromica Gafchromic MD-55-2, y se elaboro un modelo teorico para explicar los datos. Por ultimo, al precisarse el uso en RIO de la simulacion virtual y del calculo de la dosis absorbida en el paciente virtual, se ha ilustrado este apartado con la aceptacion y el estado de referencia inicial del planificador de tratamientos modulados con calculo de Monte Carlo Elekta Monaco. Para ello se utilizaron la camara de ionizacion TW31016-0104 y la matriz seven29 de PTW-Freiburg, pelicula radiocromica Gafchromic EBT-2, y diferentes maniquies. Resultados: El FMEA identifico 57 modos de fallo y efectos potenciales. No se experimentaron sucesos relativos a una administracion inadecuada de la dosis absorbida. Se identificaron las revisiones dobles y por un par como claves para reducir los riesgos asociados al equipo de profesionales involucrado en la RIO. Se identificaron tambien oportunidades de mejora con el uso de la automatizacion y el enclavamiento. En cuanto al SPC, los indices de capacidad del proceso abarcaron de 1,6 a 9,3 para un nivel de especificaciones del +/-2%. Las intervenciones simuladas alcanzaron del 2% al 34% de las sesiones de medida. Las camaras de ionizacion Farmer derivaron en direcciones opuestas en un periodo de 6 anos; aunque ello no se aprecio en los informes de calibracion del laboratorio acreditado. No derivo la camara PPC-40. En la dosimetria in vivo, las medidas de los MOSFET no se desviaron significativamente de las medidas con pelicula. Los valores centrales de las dosis absorbidas quedaron entre la dosis absorbida prescrita y la maxima, con lo que indicaron un tratamiento correcto del lecho tumoral. Las anchuras de los intervalos de confianza de las dosis absorbidas esperadas segun el modelo teorico al nivel del 95% abarcaron del 8,6% al 14,7%. Las verificaciones de Monaco resultaron satisfactorias excepto en el caso de la transferencia de datos, que obligo a cambiar el flujo de trabajo. Conclusiones: El FMEA es crucial para priorizar las intervenciones reductoras del riesgo. Tipos diferentes de procesos fallidos se pueden eliminar o paliar con tipos diferentes de tales intervenciones. El SPC puede evaluar la variabilidad inherente del procedimiento monitorizador de haces de electrones, indica cuando intervenir para devolver un proceso al estado de control y si un proceso es capaz con respecto a unas especificaciones o requisitos establecidos. Es viable realizar dosimetria in vivo con un acelerador convencional fijo y obtener resultados satisfactorios en cada localizacion estudiada a pesar de su variabilidad. El modelo teorico desarrollado puede describir con exito resultados globales, aunque no puede explicar todos los datos experimentales. Se ha mostrado que un planificador puede funcionar correctamente en condiciones de laboratorio o trabajando solo; pero puede fallar cuando se conecta con otros equipos de radioterapia. Todos estos aspectos presentados y evaluados aqui constituyen competencias actuales o futuras, y deseables, de los radiofisicos, tanto en el campo de la RIO como en la extension a la radioterapia en su conjunto.

ACUTE EXPOSURE TO TRIS (2-CHLOROETHYL) PHOSPHATE HIPPOCAMPAL NEURONAL LOSS AND IMPAIRS LEARNING IN RATS

EPA Science Inventory

Adult female, Fischer 344 rats were exposed to 275 mg/kg of tris(2- chloroethyl)phosphate (TRCP) by gavage. RCP produced consistent signs of convulsive activity within 60-90 minutes after dosing and extensive loss of CA1 hippocampal pyramidal cells when examined 7 days after dosi...

Development of quality control and instrumentation performance metrics for diffuse optical spectroscopic imaging instruments in the multi-center clinical environment

NASA Astrophysics Data System (ADS)

Keene, Samuel T.; Cerussi, Albert E.; Warren, Robert V.; Hill, Brian; Roblyer, Darren; Leproux, AnaÑ--s.; Durkin, Amanda F.; O'Sullivan, Thomas D.; Haghany, Hosain; Mantulin, William W.; Tromberg, Bruce J.

2013-03-01

Instrument equivalence and quality control are critical elements of multi-center clinical trials. We currently have five identical Diffuse Optical Spectroscopic Imaging (DOSI) instruments enrolled in the American College of Radiology Imaging Network (ACRIN, #6691) trial located at five academic clinical research sites in the US. The goal of the study is to predict the response of breast tumors to neoadjuvant chemotherapy in 60 patients. In order to reliably compare DOSI measurements across different instruments, operators and sites, we must be confident that the data quality is comparable. We require objective and reliable methods for identifying, correcting, and rejecting low quality data. To achieve this goal, we developed and tested an automated quality control algorithm that rejects data points below the instrument noise floor, improves tissue optical property recovery, and outputs a detailed data quality report. Using a new protocol for obtaining dark-noise data, we applied the algorithm to ACRIN patient data and successfully improved the quality of recovered physiological data in some cases.

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

Yang, Xi; Wang, Shanshan; Ghiviriga, Ion

A novel synthetic method to create gold based metallo–oligomers/polymers via the combination of inorganic click (iClick) with intermolecular aurophilic interactions is demonstrated. Complexes [PEt 3Au] 4(μ-N 3C 2C 6H 5) (1) and [PPhMe 2Au] 43C 2C 6H 5) (2) and {[PEt 3Au] 4[(μ-N 3C 2) 2-9,9-dihexyl-9H-fluorene]} n (8) have been synthesized via iClick. The tetranuclear structures of 1 and 2, induced by aurophilic bonding, are confirmed in the solid state through single crystal X-ray diffraction experiments and in solution via variable temperature NMR spectroscopy. The extended 1D structure of 8 is constructed by aurophilic induced self-assembly. 1H DOSY NMR analysismore » reveals that the aurophilic bonds in 1, 2, and 8 are retained in the solution phase. The degree of polymerization within complex 8 is temperature and concentration dependent, as determined by 1H DOSY NMR. The complex 8 is a rare example of a solution stable higher ordered structure linked by aurophilic interactions.« less

Analytical challenges in drug counterfeiting and falsification-The NMR approach.

PubMed

Holzgrabe, Ulrike; Malet-Martino, Myriam

2011-06-25

Counterfeiting of products is a global problem. As long as clothes, clocks, leather wear, etc. are faked there is no danger, but when it comes to drugs, counterfeiting can be life-threatening. In the last years sub-standard active pharmaceutical ingredients (APIs) were found more often even though the use of the quality-ensuring methods of international pharmacopoeias should have detected additional impurities and the low content of the API. Methods orthogonal to the separating methods used in the pharmacopoeias are necessary to find counterfeits. Beside Raman and NIR spectroscopies as well as powder X-ray analysis, NMR spectroscopy being a primary ratio method of measurement is highly suitable to identify and quantify a drug and its related substances as well as to recognize a drug of sub-standard quality. DOSY experiments are suitable to identify the ingredients of formulations and therefore to identify wrong and/or additional ingredients. This review gives an overview of the application of quantitative NMR spectroscopy and DOSY NMR in anticounterfeiting. Copyright © 2010 Elsevier B.V. All rights reserved.

DESI-MS imaging and NMR spectroscopy to investigate the influence of biodiesel in the structure of commercial rubbers.

PubMed

Silva, Lorena M A; Alves Filho, Elenilson G; Simpson, André J; Monteiro, Marcos R; Cabral, Elaine; Ifa, Demian; Venâncio, Tiago

2017-10-01

Biodiesel has been introduced as an energetic matrix in several countries around the world. However, the affinity of biodiesel with the components of petrodiesel engines is a growing concern. In order to obtain information regarding the effect of biodiesel on the rubber structure, nuclear magnetic resonance technics under a new technology named as comprehensive multiphase (CMP NMR) and the imaging through desorption electrospray ionization mass spectrometry (DESI-MS imaging) were used. The 1 H CMP-DOSY NMR showed the entrapped fuel into the rubber cavities, which the higher constraint caused by the rubber structure is related to the smaller diffusion coefficient. The less affected type of rubber by biodiesel was ethylene-propylene-diene monomer (EPDM), and the most affected was synthetic rubber nitrile (NBR). The 13 C CMP MAS-SPE experiments also confirmed that the internal region of EPDM was less accessible to the biodiesel molecules (no fuels detected) while other rubbers were more susceptible to the penetration of the fuel. DESI-MS imaging revealed for the first time the topography of the rubbers exposed to fuels. The biodiesel molecules entrapped at the EPDM and NBR pores were in oxidized form, which might degrade the rubber structure at long exposure time. The employed technics enabled the study of dynamic and molecular structure of the mixing complex multiphase. The DOSY under CMP used in this study could prove helpful in assessing the interactions throughout all physical phases (liquid, solid, and gel or semi-solid) by observing swellability caused by the fuel in the rubber. In addition, the DESI-MS was especially valuable to detect the degradation products of biodiesel entangled at the rubber structure. In our knowledge, this was the first report in which chemical changes of commercial rubbers induced by biodiesel and petrodiesel were investigated by means of DESI-MS and DOSY NMR. Copyright © 2017 Elsevier B.V. All rights reserved.

Application of Finite Element Modeling Methods in Magnetic Resonance Imaging-Based Research and Clinical Management

NASA Astrophysics Data System (ADS)

Fwu, Peter Tramyeon

The medical image is very complex by its nature. Modeling built upon the medical image is challenging due to the lack of analytical solution. Finite element method (FEM) is a numerical technique which can be used to solve the partial differential equations. It utilized the transformation from a continuous domain into solvable discrete sub-domains. In three-dimensional space, FEM has the capability dealing with complicated structure and heterogeneous interior. That makes FEM an ideal tool to approach the medical-image based modeling problems. In this study, I will address the three modeling in (1) photon transport inside the human breast by implanting the radiative transfer equation to simulate the diffuse optical spectroscopy imaging (DOSI) in order to measurement the percent density (PD), which has been proven as a cancer risk factor in mammography. Our goal is to use MRI as the ground truth to optimize the DOSI scanning protocol to get a consistent measurement of PD. Our result shows DOSI measurement is position and depth dependent and proper scanning scheme and body configuration are needed; (2) heat flow in the prostate by implementing the Penne's bioheat equation to evaluate the cooling performance of regional hypothermia during the robot assisted radical prostatectomy for the individual patient in order to achieve the optimal cooling setting. Four factors are taken into account during the simulation: blood abundance, artery perfusion, cooling balloon temperature, and the anatomical distance. The result shows that blood abundance, prostate size, and anatomical distance are significant factors to the equilibrium temperature of neurovascular bundle; (3) shape analysis in hippocampus by using the radial distance mapping, and two registration methods to find the correlation between sub-regional change to the age and cognition performance, which might not reveal in the volumetric analysis. The result gives a fundamental knowledge of normal distribution in young preadolescent children who may be compared to children with, or at risk of, neurological diseases for early diagnosis.

Organogold oligomers: Exploiting iClick and aurophilic cluster formation to prepare solution stable Au 4 repeating units

DOE PAGES

Yang, Xi; Wang, Shanshan; Ghiviriga, Ion; ...

2015-05-19

A novel synthetic method to create gold based metallo–oligomers/polymers via the combination of inorganic click (iClick) with intermolecular aurophilic interactions is demonstrated. Complexes [PEt 3Au] 4(μ-N 3C 2C 6H 5) (1) and [PPhMe 2Au] 43C 2C 6H 5) (2) and {[PEt 3Au] 4[(μ-N 3C 2) 2-9,9-dihexyl-9H-fluorene]} n (8) have been synthesized via iClick. The tetranuclear structures of 1 and 2, induced by aurophilic bonding, are confirmed in the solid state through single crystal X-ray diffraction experiments and in solution via variable temperature NMR spectroscopy. The extended 1D structure of 8 is constructed by aurophilic induced self-assembly. 1H DOSY NMR analysismore » reveals that the aurophilic bonds in 1, 2, and 8 are retained in the solution phase. The degree of polymerization within complex 8 is temperature and concentration dependent, as determined by 1H DOSY NMR. The complex 8 is a rare example of a solution stable higher ordered structure linked by aurophilic interactions.« less

A Three-Dimensional DOSY HMQC Experiment for the High-Resolution Analysis of Complex Mixtures

NASA Astrophysics Data System (ADS)

Barjat, Hervé; Morris, Gareth A.; Swanson, Alistair G.

1998-03-01

A three-dimensional experiment is described in which NMR signals are separated according to their proton chemical shift,13C chemical shift, and diffusion coefficient. The sequence is built up from a stimulated echo sequence with bipolar field gradient pulses and a conventional decoupled HMQC sequence. Results are presented for a model mixture of quinine, camphene, and geraniol in deuteriomethanol.

[In vitro study over statins effects on cellular growth curves and its reversibility with mevalonate].

PubMed

Millan Núñez-Cortés, Jesús; Alvarez Rodriguez, Ysmael; Alvarez Novés, Granada; Recarte Garcia-Andrade, Carlos; Alvarez-Sala Walther, Luis

2014-01-01

HMG-CoA-Reductase inhibitors, also known as statins, are currently the most powerful cholesterol-lowering drugs available on the market. Clinical trials and experimental evidence suggest that statins have heavy anti-atherosclerotic effects. These are in part consequence of lipid lowering but also result from pleiotropic actions of the drugs. These so-called pleiotropic properties affect various aspects of cell function, inflammation, coagulation, and vasomotor activity. These effects are mediated either indirectly through LDL-c reduction or via a direct effect on cellular functions. Although many of the pleiotropic properties of statins may be a class effect, some may be unique to certain agents and account for differences in their pharmacological activity. So, although statins typically have similar effects on LDL-c levels, differences in chemical structure and pharmacokinetic profile can lead to variations in pleiotropic effects. In this paper we analize the in vitro effects of different statins over different cell lines from cells implicated in atherosclerotic process: endothelial cells, fibroblasts, and vascular muscular cells. In relation with our results we can proof that the effects of different dosis of different statins provides singular effects over growth curves of different cellular lines, a despite of a class-dependent effects. So, pleiotropic effects and its reversibility with mevalonate are different according with the molecule and the dosis. Copyright © 2013 Elsevier España, S.L. y SEA. All rights reserved.

Application of diffusion-edited and solvent suppression ¹H-NMR to the direct analysis of markers in valerian-hop liquid herbal products.

PubMed

Prieto, Jose M; Mellinas-Gomez, Maria; Zloh, Mire

2016-01-01

The rising trend to consume herbal products for the treatment and/or prevention of minor ailments together with their chemical and pharmacological complexity means there is an urgent need to develop new approaches to their quality and stability. This work looks at the application of one-dimensional diffusion-edited (1)H-NMR spectroscopy (1D DOSY) and (1)H-NMR with suppression of the ethanol and water signals to the characterisation of quality and stability markers in multi-component herbal medicines/food supplements. The experiments were performed with commercial tinctures of Valeriana officinalis L. (valerian), expired and non-expired, as well as its combination with Hummulus lupulus L. (hops), which is one of the most popular blends of relaxant herbs. These techniques did not require purification or evaporation of components for the qualitative analysis of the mixture, but only the addition of D2 O and TSP. The best diagnostic signals were found at δ 7 ppm (H-11, valerenic acid), δ 4.2 ppm (H-1, hydroxyvalerenic acid) and δ 1.5-1.8 ppm (methyl groups in prenylated moieties, α-acids/prenylated flavones). This work concludes on the potential value of 1D DOSY (1)H-NMR to provide additional assurance of quality in complex natural mixtures. Copyright © 2016 John Wiley & Sons, Ltd.

Temperature responses to infusion of electrolytes during exercise

NASA Technical Reports Server (NTRS)

Greenleaf, J. E.; Kozlowski, S.; Kaciuba-Uscilko, H.; Nazar, K.; Brzezinska, Z.

1975-01-01

Past studies on the influence of various metal ions on heat regulation in mammals are reviewed, and results of a study on the effect of Na and citrate in isotonic and hypertonic concentrations on temperature elevation during exercise in dogs are presented. Hypertonic administration of Na before or during treadmill running and dosis of citrate during treadmill running significantly raised core temperature over controls and isotonic cases. Thus the higher the plasma Na-osmotic concentration, the greater the inhibition of heat dissipation.

Interactions of poly(amidoamine) dendrimers with human serum albumin: binding constants and mechanisms.

PubMed

Giri, Jyotsnendu; Diallo, Mamadou S; Simpson, André J; Liu, Yi; Goddard, William A; Kumar, Rajeev; Woods, Gwen C

2011-05-24

The interactions of nanomaterials with plasma proteins have a significant impact on their in vivo transport and fate in biological fluids. This article discusses the binding of human serum albumin (HSA) to poly(amidoamine) [PAMAM] dendrimers. We use protein-coated silica particles to measure the HSA binding constants (K(b)) of a homologous series of 19 PAMAM dendrimers in aqueous solutions at physiological pH (7.4) as a function of dendrimer generation, terminal group, and core chemistry. To gain insight into the mechanisms of HSA binding to PAMAM dendrimers, we combined (1)H NMR, saturation transfer difference (STD) NMR, and NMR diffusion ordered spectroscopy (DOSY) of dendrimer-HSA complexes with atomistic molecular dynamics (MD) simulations of dendrimer conformation in aqueous solutions. The binding measurements show that the HSA binding constants (K(b)) of PAMAM dendrimers depend on dendrimer size and terminal group chemistry. The NMR (1)H and DOSY experiments indicate that the interactions between HSA and PAMAM dendrimers are relatively weak. The (1)H NMR STD experiments and MD simulations suggest that the inner shell protons of the dendrimers groups interact more strongly with HSA proteins. These interactions, which are consistently observed for different dendrimer generations (G0-NH(2)vs G4-NH(2)) and terminal groups (G4-NH(2)vs G4-OH with amidoethanol groups), suggest that PAMAM dendrimers adopt backfolded configurations as they form weak complexes with HSA proteins in aqueous solutions at physiological pH (7.4).

Radiosensibilisierung durch BRAF Inhibitoren.

PubMed

Strobel, Sophia Boyoung; Pätzold, Sylvie; Zimmer, Lisa; Jensen, Alexandra; Enk, Alexander; Hassel, Jessica Cecile

2017-07-01

In der letzten Zeit wurden in der Literatur vermehrt erhöhte Hauttoxizitäten während einer Kombinationstherapie mit BRAF Inhibitoren und Radiotherapie beschrieben. Wir berichten über sieben Melanompatienten in einem nicht resezierbaren Stadium III oder IV, die eine kombinierte Behandlung aus Bestrahlung und BRAF-Inhibitor erhielten. Bei allen Patienten konnte durch die Kombinationstherapie ein gutes lokales Ansprechen erreicht werden. Nur bei zwei Patienten wurde eine schwere Radiodermatitis (CTCAE Grad 3 bzw. 4) beobachtet. Bei diesen Patienten, die beide Vemurafenib erhielten, trat die Radiodermatitis nach ein bzw. zwei Wochen auf und resultierte in einer Unterbrechung der BRAF-Inhibitor Behandlung.. Die kumulative Dosis bis zum Zeitpunkt der Strahlendermatitis betrug 10 Gy bzw. 35 Gy. Bei allen anderen Vemurafenibpatienten konnten nur milde Reaktionen im Sinne einer Radiodermatitis CTCAE Grad 2, beim Dabrafenibpatienten CTCAE Grade 1 diagnostiziert werden. Bei einem Patienten wurde eine Recalldermatitis nach 14 Tagen einer beendeten Strahlentherapie mit einer kumulativen Dosis von 30 Gy diagnostiziert. Schwere Toxizitätsreaktionen der Haut unter einer BRAF-Inhibitionen treten nicht häufig auf und sind meistens gut therapierbar. Deshalb sollte die Kombinationstherapie bei aggressiv wachsenden Melanomen eine Therapieoption bleiben. Obwohl ein erhöhtes Risiko der Hauttoxizität unter einer Kombinationstherapie von Radiatio und BRAF-Inhibitoren besteht, wird diese von den meisten Patienten gut toleriert. Sequenzielle Therapie anstelle von gleichzeitiger Behandlung scheint die Toxizitätreaktionen nicht zu verhindern. © 2017 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Improving reliability of chemometric models for authentication of species origin of heparin by switching from 1D to 2D NMR experiments.

PubMed

Monakhova, Yulia B; Fareed, Jawed; Yao, Yiming; Diehl, Bernd W K

2018-05-10

Nuclear magnetic resonance (NMR) spectroscopy is regarded as one of the most powerful and versatile analytical approaches to assure the quality of heparin preparations. In particular, it was recently demonstrated that by using 1 H NMR coupled with chemometrics heparin and low molecular weight heparin (LMWH) samples derived from three major animal species (porcine, ovine and bovine) can be differentiated [Y.B. Monakhova et al. J. Pharm. Anal. 149 (2018) 114-119]. In this study, significant improvement of existing chemometric models was achieved by switching to 2D NMR experiments (heteronuclear multiple-quantum correlation (HMQC) and diffusion-ordered spectroscopy (DOSY)). Two representative data sets (sixty-nine heparin and twenty-two LMWH) belonged to different batches and distributed by different commercial companies were investigated. A trend for animal species differentiation was observed in the principal component analysis (PCA) score plot built based on the DOSY data. A superior model was constructed using HMQC experiments, where individual heparin (LMWH) clusters as well as their blends were clearly differentiated. The predictive power of different classification methods as well as unsupervised techniques (independent components analysis, ICA) clearly proved applicability of the model for routine heparin and LMWH analysis. The switch from 1D to 2D NMR techniques provides a wealth of additional information, which is beneficial for multivariate modeling of NMR spectroscopic data for heparin preparations. Copyright © 2018 Elsevier B.V. All rights reserved.

Arthroscopic Bankart Repair Versus Open Bristow-Latarjet for Shoulder Instability: A Matched-Pair Multicenter Study Focused on Return to Sport.

PubMed

Blonna, Davide; Bellato, Enrico; Caranzano, Francesco; Assom, Marco; Rossi, Roberto; Castoldi, Filippo

2016-12-01

The arthroscopic Bankart repair and open Bristow-Latarjet procedure are the 2 most commonly used techniques to treat recurrent shoulder instability. To compare in a case control-matched manner the 2 techniques, with particular emphasis on return to sport after surgery. Cohort study; Level of evidence, 3. A study was conducted in 2 hospitals matching 60 patients with posttraumatic recurrent anterior shoulder instability with a minimum follow-up of 2 years (30 patients treated with arthroscopic Bankart procedure and 30 treated with open Bristow-Latarjet procedure). Patients with severe glenoid bone loss and revision surgeries were excluded. In one hospital, patients were treated with arthroscopic Bankart repair using anchors; in the other, patients underwent the Bristow-Latarjet procedure. Patients were matched according to age at surgery, type and level of sport practiced before shoulder instability (Degree of Shoulder Involvement in Sports [DOSIS] scale), and number of dislocations. The primary outcomes were return to sport (Subjective Patient Outcome for Return to Sports [SPORTS] score), rate of recurrent instability, Oxford Shoulder Instability Score (OSIS), Subjective Shoulder Value (SSV), Western Ontario Shoulder Instability Index (WOSI), and range of motion (ROM). After a mean follow-up of 5.3 years (range, 2-9 years), patients who underwent arthroscopic Bankart repair obtained better results in terms of return to sport (SPORTS score: 8 vs 6; P = .02) and ROM in the throwing position (86° vs 79°; P = .01), and they reported better subjective perception of the shoulder (SSV: 86% vs 75%; P = .02). No differences were detectable using the OSIS or WOSI. The rate of recurrent instability was not statistically different between the 2 groups (Bankart repair 10% vs Bristow-Latarjet 0%; P = .25), although the study may have been underpowered to detect a clinically important difference in this parameter. The multiple regression analysis showed that the independent variables associated with return to sport were preoperative DOSIS scale, type of surgery, and recurrent dislocations after surgery. Patients who played sports with high upper extremity involvement (eg, swimming, rugby, martial arts) at a competitive level (DOSIS scale 9 or 10) had a lower level of return to sport with both repair techniques. Arthroscopic stabilization using anchors provided better return to sport and subjective perception of the shoulder compared with the open Bristow-Latarjet procedure in the population studied. Recurrence may be higher in the arthroscopic Bankart group; further study is needed on this point. © 2016 The Author(s).

La enumeración de la soltería femenina en los censos de población: sesgo y propuesta de corrección

PubMed Central

McCaa, Robert; Esteve, Albert; Garcia, Joan

2013-01-01

Esta investigación tiene como objetivo investigar el efecto que la disolución de las uniones consensuales tiene en los niveles de soltería que proporciona el Censo de Población, niveles derivados de la variable estado civil. Para ello comparamos los datos censales con los de la Encuestas de Demografía y Salud (de ahora en adelante DHS) en aquellos países y años para los que disponemos de ambas fuentes en el mismo año o años adyacentes (Bolivia, Brasil, Colombia y Perú). Los resultados muestran claramente que las proporciones de nunca unidas derivadas de la variable censal ’Estado civil’ son sistemáticamente más elevadas que las estimadas a partir de las DHS. La razón de esta sobreestimación obedece al hecho de que personas que estuvieron en unión libre en el pasado se declaran solteras en el momento del Censo. La elevada proporción de mujeres solteras que tienen hijos según el Censo es una prueba de ello y a su vez una solución efectiva para corregir el sesgo. PMID:25593515

Detection of Potential TNA and RNA Nucleoside Precursors in a Prebiotic Mixture by Pure Shift Diffusion-Ordered NMR Spectroscopy

PubMed Central

Islam, Saidul; Aguilar, Juan A; Powner, Matthew W; Nilsson, Mathias; Morris, Gareth A; Sutherland, John D

2013-01-01

In the context of prebiotic chemistry, one of the characteristics of mixed nitrogenous-oxygenous chemistry is its propensity to give rise to highly complex reaction mixtures. There is therefore an urgent need to develop improved spectroscopic techniques if onerous chromatographic separations are to be avoided. One potential avenue is the combination of pure shift methodology, in which NMR spectra are measured with greatly improved resolution by suppressing multiplet structure, with diffusion-ordered spectroscopy, in which NMR signals from different species are distinguished through their different rates of diffusion. Such a combination has the added advantage of working with intact mixtures, allowing analyses to be carried out without perturbing mixtures in which chemical entities are part of a network of reactions in equilibrium. As part of a systems chemistry approach towards investigating the self-assembly of potentially prebiotic small molecules, we have analysed the complex mixture arising from mixing glycolaldehyde and cyanamide, in a first application of pure shift DOSY NMR to the characterisation of a partially unknown reaction composition. The work presented illustrates the potential of pure shift DOSY to be applied to chemistries that give rise to mixtures of compounds in which the NMR signal resolution is poor. The direct formation of potential RNA and TNA nucleoside precursors, amongst other adducts, was observed. These preliminary observations may have implications for the potentially prebiotic assembly chemistry of pyrimidine threonucleotides, and therefore of TNA, by using recently reported chemistries that yield the activated pyridimidine ribonucleotides. PMID:23371787

Celulas solares e sensores de filme fino de silicio depositados sobre substratos flexiveis =

NASA Astrophysics Data System (ADS)

Pinto, Emilio Sergio Marins Vieira

Celulas solares flexiveis de filmes finos de silicio sao geralmente fabricadas a baixa temperatura sobre substratos de plastico ou a mais elevadas temperaturas sobre folhas de aco. Esta tese reporta o estudo da deposicao de filmes finos sobre diferentes substratos de plastico, transparentes e coloridos, para celulas solares do tipo sobrestrato e substrato, respectivamente. Como objetivo co-lateral, os filmes dopados depositados sobre plastico foram usados como sensores de deformacao, utilizando as suas propriedades piezo-resistivas. Elevadas taxas de deposicao dos filmes de silicio depositados sobre plastico foram obtidas a baixa temperatura do substrato (150ºC) por rf-PECVD. A influencia de diferentes parametros de deposicao sobre as propriedades e taxa de deposicao dos filmes resultantes foram estudados e correlacionados. Celulas solares de filmes finos de silicio amorfo e microcristalino foram desenvolvidas a baixas temperaturas sobre plasticos. Eficiencias de 5 - 6.5% foram alcancadas para as celulas amorfas e 7.5% para as celulas microcristalinas. Efeitos de aprisionamento da luz foram estudados atraves da texturizacao por ablacao laser de substratos de plastico e corrosao umida de TCO sobre plastico. Filmes finos de silicio microcristalino, depositados por HW-CVD, com fator piezoresistivo de -32.2, foram usados para fabricar sensores de deformacao em uma membrana plastica muito fina (15 μm). Estruturas de teste em textil e a miniaturizacao dos sensores piezoresistivos depositados sobre substratos flexiveis de poliimida foram abordados.

[Oral flaxseed oil (Linum usitatissimum) in the treatment for dry-eye Sjögren's syndrome patients].

PubMed

Pinheiro, Manuel Neuzimar; dos Santos, Procópio Miguel; dos Santos, Regina Cândido Ribeiro; Barros, Jeison de Nadai; Passos, Luiz Fernando; Cardoso Neto, José

2007-01-01

To evaluate if oral flaxseed oil (Linum usitatissimum), which reduces the inflammation in rheumatoid arthritis, may help keratoconjunctivitis sicca's treatment in Sjögren's syndrome patients. In a randomized clinical trial, 38 female patients with rheumatoid arthritis or systemic lupus erithematosus associated with keratoconjunctivitis sicca and Sjögren's syndrome were consecutively selected from patients of the Department of Rheumatology of the Amazonas University Hospital. Keratoconjunctivitis sicca diagnosis was based on a dry-eye symptom survey score (Ocular Surface Disease Index - OSDI), Schirmer-I test, fluorescein break-up time, 1% Rose Bengal staining of ocular surface measured by the van Bijsterveld scale. All patients had ocular surface inflammation evaluated and quantified by conjunctival impression cytology, before and after the study. The subjects were divided into three groups with 13 (Group I), 12 (Group II) and 13 (Group III) patients. Group I received flaxseed oil capsules with a final 1 g/day dosis, Group II flaxseed oil capsules with a final 2 g/day dosis and Group III - controls - placebo, for 180 days. Comparing the results at the beginning and at the end of the treatment, statistically significant changes (p<0.05) in symptoms (OSDI), ocular surface inflammation quantified by conjunctival impression cytology, Schirmer-I test and fluorescein break-up time occurred in Groups I e II when compared to controls. Therapy with oral flaxseed oil capsules 1 or 2 g/day reduces ocular surface inflammation and ameliorates the symptoms of keratoconjunctivitis sicca in Sjögren's syndrome patients. Long-term studies are needed to confirm the role of this therapy for keratoconjunctivitis sicca in Sjögren's syndrome.

Temperature-dependent solubility transition of Na₂SO₄ in water and the effect of NaCl therein: solution structures and salt water dynamics.

PubMed

Bharmoria, Pankaj; Gehlot, Praveen Singh; Gupta, Hariom; Kumar, Arvind

2014-11-06

Dual, aqueous solubility behavior of Na2SO4 as a function of temperatures is still a natural enigma lying unresolved in the literature. The solubility of Na2SO4 increases up to 32.38 °C and decreases slightly thereafter at higher temperatures. We have thrown light on this phenomenon by analyzing the Na2SO4-water clusters (growth and stability) detected from temperature-dependent dynamic light scattering experiments, solution compressibility changes derived from the density and speed of sound measurements, and water structural changes/Na2SO4 (ion pair)-water interactions observed from the FT-IR and 2D DOSY (1)H NMR spectroscopic investigations. It has been observed that Na2SO4-water clusters grow with an increase in Na2SO4 concentration (until the solubility transition temperature) and then start decreasing afterward. An unusual decrease in cluster size and solution compressibility has been observed with the rise in temperature for the Na2SO4 saturated solutions below the solubility transition temperature, whereas an inverse pattern is followed thereafter. DOSY experiments have indicated different types of water cluster species in saturated solutions at different temperatures with varying self-diffusion coefficients. The effect of NaCl (5-15 wt %) on the solubility behavior of Na2SO4 at different temperatures has also been examined. The studies are important from both fundamental and industrial application points of view, for example, toward the clean separation of NaCl and Na2SO4 from the effluent streams of textile and tannery industries.

Demetrius Cantemir: the first account of transabodominal approach to repair groin hernia.

PubMed

Nicolau, A E

2009-01-01

The first description of the transabdominal approach for hernia repair was written by Demetrius Cantemir, Prince of Moldavia and encyclopedic scholar, in his 1716 Latin manuscript "Incrementa et decrementa Aulae Othomaniae" ("The history of the Growth and Decay of the Ottoman Empire"). This manuscript was one of the most important in Eastern Europe at the time. It was first translated in English in 1734 by N. Tyndal, and all subsequent translations into various other languages were based on this english version. The original manuscript now belongs to the Houghton Library of Harvard University, where it was recently discovered in 1984 by V. Candea. Our article presents for the first time the complete account of the surgical procedure performed by Albanian physicians in the prince's palace in Constantinopol. The patient was the Prince's secretary. There is a detailed description of the operation, postoperative therapy and the medical course to recovery. The text presented is translated in English from Annotations of Volume Two, chapter four. We consider it worthwhile to present to the medical community this valuable but less known contribution to the history of medicine.

[An automated registry program for nosocomial infections].

PubMed

Castañón-González, Jorge Alberto; Polanco-González, Carlos; Samaniego-Mendoza, José Lino; Buhse, Thomas

2014-12-01

Las infecciones nosocomiales presentan un gran reto para la medicina hospitalaria, en general, y para las Unidades de Cuidados Intensivos, en particular. Su elevada prevalencia, la gran morbilidad y mortalidad asociadas, el incremento de la estancia hospitalaria y, en consecuencia, los costos de la atención médica han hecho que los programas de vigilancia, control y prevención de infecciones nosocomiales sean una parte toral de los protocolos de seguridad para el paciente y un indicador de calidad de la atención médica.

NMR relaxometric probing of ionic liquid dynamics and diffusion under mesoscopic confinement within bacterial cellulose ionogels

NASA Astrophysics Data System (ADS)

Smith, Chip J.; Gehrke, Sascha; Hollóczki, Oldamur; Wagle, Durgesh V.; Heitz, Mark P.; Baker, Gary A.

2018-05-01

Bacterial cellulose ionogels (BCIGs) represent a new class of material comprising a significant content of entrapped ionic liquid (IL) within a porous network formed from crystalline cellulose microfibrils. BCIGs suggest unique opportunities in separations, optically active materials, solid electrolytes, and drug delivery due to the fact that they can contain as much as 99% of an IL phase by weight, coupled with an inherent flexibility, high optical transparency, and the ability to control ionogel cross-sectional shape and size. To allow for the tailoring of BCIGs for a multitude of applications, it is necessary to better understand the underlying principles of the mesoscopic confinement within these ionogels. Toward this, we present a study of the structural, relaxation, and diffusional properties of the ILs, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([emim][Tf2N]) and 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([bmpy][Tf2N]), using 1H and 19F NMR T1 relaxation times, rotational correlation times, and diffusion ordered spectroscopy (DOSY) diffusion coefficients, accompanied by molecular dynamics (MD) simulations. We observed that the cation methyl groups in both ILs were primary points of interaction with the cellulose chains and, while the pore size in cellulose is rather large, [emim]+ diffusion was slowed by ˜2-fold, whereas [Tf2N]- diffusion was unencumbered by incorporation in the ionogel. While MD simulations of [bmpy][Tf2N] confinement at the interface showed a diffusion coefficient decrease roughly 3-fold compared to the bulk liquid, DOSY measurements did not reveal any significant changes in diffusion. This suggests that the [bmpy][Tf2N] alkyl chains dominate diffusion through formation of apolar domains. This is in contrast to [emim][Tf2N] where delocalized charge appears to preclude apolar domain formation, allowing interfacial effects to be manifested at a longer range in [emim][Tf2N].

Tracking "apolar" NMe4+ ions within two polyoxothiomolybdates that have the same pores: smaller clathrate and larger highly porous clusters in action.

PubMed

Korenev, Vladimir S; Boulay, Antoine G; Haouas, Mohamed; Bannani, Fatma; Fedin, Vladimir P; Sokolov, Maxim N; Terazzi, Emmanuel; Garai, Somenath; Müller, Achim; Taulelle, Francis; Marrot, Jérôme; Leclerc, Nathalie; Floquet, Sébastien; Cadot, Emmanuel

2014-03-10

Two nanosized polyoxothiometalates were synthesized based on linking oxomolybdate building blocks with {Mo2O2S2}(2+) groups. Remarkably, both compounds are formed selectively primarily upon changing the related concentrations in a logical way; they exhibit common structural features based on the same {Mo9O6S3}-type pores, which result in connections between {Mo6O21} pentagons and {Mo2O2S2}(2+) linkers. Whereas the much larger spherical Mo132-type Keplerate contains twenty pores, the smaller Mo63 -type cluster remarkably contains only two. The two compounds and a similar Keplerate exhibit interesting supramolecular properties related to interactions with the unusual predominantly apolar NMe4(+) cations. Structural characterization of the Mo63 -type compound reveals in the solid state a clathrate-like species that contains four NMe4(+) cations embedded in two types of structurally well-adapted pockets. Related NMR spectroscopic investigations in solution using NMe4(+) as the NMR spectroscopic probe are in agreement with the solid-state description. (1)H NMR spectroscopic experiments (1D variable-temperature, 2D total correlation spectroscopy (TOCSY), exchange spectroscopy (EXSY), and diffusion-ordered spectroscopy (DOSY)) feature firmly immobilized and mobile NMe4(+) ions in relationship with the type of host-guest arrangements. The use of the (1)H NMR DOSY spectroscopic methodology has been successfully applied to track the interactions of the NMe4(+) cations with the {Mo9O6S3} pores of a sulfurated Keplerate, thereby allowing the first quantitative analysis of this type of plugging process. The stability constant K=(210±20) mol(-1)  L is discussed related to the character of the process. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High-performance liquid chromatography with nuclear magnetic resonance detection applied to organosilicon polymers. Part 2. Comparison with other methods.

PubMed

Blechta, Vratislav; Kurfürst, Milan; Sýkora, Jan; Schraml, Jan

2007-03-23

LC-NMR utilizing (1)H and (29)Si NMR spectroscopy is ideally suited for the analysis of silicones. It is shown that reversed phase gradient LC-NMR surpasses standard gel permeation chromatography (GPC) and diffusion ordered spectroscopy (DOSY) in the analysis of model hydride terminated polydimethylsiloxane. (1)H and (29)Si NMR in the stopped-flow arrangement leads to full identification of the components. Concentration gradient introduces a dependence of the (29)Si shifts on solvent composition, this dependence can be substantially reduced by a proposed method of referencing. It is shown that the ADEQUATE version of powerful but insensitive 2D INADEQUATE experiment can be used for complete line assignment.

Elaboration of thermoresponsive supramolecular diblock copolymers in water from complementary CBPQT4+ and TTF end-functionalized polymers.

PubMed

Sambe, Léna; Stoffelbach, François; Poltorak, Katarzyna; Lyskawa, Joël; Malfait, Aurélie; Bria, Marc; Cooke, Graeme; Woisel, Patrice

2014-02-01

A well-defined poly(N-isopropyl acrylamide) 1 incorporating at one termini a cyclobis(paraquat-p-phenylene) (CBPQT(4+)) recognition unit is prepared via a RAFT polymerization followed by a copper-catalyzed azide-alkyne cycloaddition (CuAAC). (1)H NMR (1D, DOSY), UV-vis and ITC experiments reveal that polymer 1 is able of forming effective host-guest complexes with tetrathiafulvalene (TTF) end-functionalized polymers in water, thereby leading to the formation of non-covalently-linked double-hydrophilic block copolymers. The effect of the temperature on both the LCST phase transition of 1 and its complexes and on CBPQT(4+)/TTF host-guest interactions is investigated. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

PubMed

Fumis, María Agustina; Bidabehere, María Belén; Moyano, Yohana; Sardoy, Agustina; Gubiani, María Laura; Boldrini, María Pía; Pinardi, Beatriz Alicia

2017-09-08

La fascitis necrotizante por estrepotococo del grupo A es una infección infrecuente del tejido subcutáneo  y de la fascia, con una tasa de mortalidad elevada debido a su rápida progresión a shock y fallo multiorgánico. Se desarrolla generalmente en extremidades tras un traumatismo o lesión previa. El diagnóstico temprano es esencial así como también el manejo rápido y agresivo. Presentamos un caso de fascitis necrotizante de evolución rápida a pesar del diagnóstico precoz y tratamiento específico instaurado.

A supramolecular miktoarm star polymer based on porphyrin metal complexation in water.

PubMed

Hou, Zhanyao; Dehaen, Wim; Lyskawa, Joël; Woisel, Patrice; Hoogenboom, Richard

2017-07-25

A novel supramolecular miktoarm star polymer was successfully constructed in water from a pyridine end-decorated polymer (Py-PmDEGA) and a metalloporphyrin based star polymer (ZnTPP-(PEG) 4 ) via metal-ligand coordination. The Py-PmDEGA moiety was prepared via a combination of reversible addition-fragmentation chain transfer polymerization (RAFT) and subsequent aminolysis and Michael addition reactions to introduce the pyridine end-group. The ZnTPP(PEG) 4 star-polymer was synthesized by the reaction between tetrakis(p-hydroxyphenyl)porphyrin and toluenesulfonyl-PEG, followed by insertion of a zinc ion into the porphyrin core. The formation of a well-defined supramolecular AB 4 -type miktoarm star polymer was unambiguously demonstrated via UV-Vis spectroscopic titration, isothermal titration calorimetry (ITC) and diffusion ordered NMR spectroscopy (DOSY).

Exploiting different active silicon detectors in the International Space Station: ALTEA and DOSTEL galactic cosmic radiation (GCR) measurements

NASA Astrophysics Data System (ADS)

Narici, Livo; Berger, Thomas; Burmeister, Sönke; Di Fino, Luca; Rizzo, Alessandro; Matthiä, Daniel; Reitz, Günther

2017-08-01

The solar system exploration by humans requires to successfully deal with the radiation exposition issue. The scientific aspect of this issue is twofold: knowing the radiation environment the astronauts are going to face and linking radiation exposure to health risks. Here we focus on the first issue. It is generally agreed that the final tool to describe the radiation environment in a space habitat will be a model featuring the needed amount of details to perform a meaningful risk assessment. The model should also take into account the shield changes due to the movement of materials inside the habitat, which in turn produce changes in the radiation environment. This model will have to undergo a final validation with a radiation field of similar complexity. The International Space Station (ISS) is a space habitat that features a radiation environment inside which is similar to what will be found in habitats in deep space, if we use measurements acquired only during high latitude passages (where the effects of the Earth magnetic field are reduced). Active detectors, providing time information, that can easily select data from different orbital sections, are the ones best fulfilling the requirements for these kinds of measurements. The exploitation of the radiation measurements performed in the ISS by all the available instruments is therefore mandatory to provide the largest possible database to the scientific community, to be merged with detailed Computer Aided Design (CAD) models, in the quest for a full model validation. While some efforts in comparing results from multiple active detectors have been attempted, a thorough study of a procedure to merge data in a single data matrix in order to provide the best validation set for radiation environment models has never been attempted. The aim of this paper is to provide such a procedure, to apply it to two of the most performing active detector systems in the ISS: the Anomalous Long Term Effects in Astronauts (ALTEA) instrument and the DOSimetry TELescope (DOSTEL) detectors, applied in the frame of the DOSIS and DOSIS 3D project onboard the ISS and to present combined results exploiting the features of each of the two apparatuses.

Vulnerability to alcohol consumption, spiritual transcendence and psychosocial well-being: test of a theory.

PubMed

Heredia, Luz Patricia Díaz; Sanchez, Alba Idaly Muñoz

2016-06-07

to demonstrate the relations among vulnerability, self-transcendence and well-being in the young adult population and the effect of each of these variables on the adoption of low-risk consumption conducts. quantitative and cross-sectional correlation study using structural equations analysis to test the relation among the variables. an inverse relation was evidenced between vulnerability to alcohol consumption and spiritual transcendence (β-0.123, p 0.025) and a direct positive relation between spiritual transcendence and psychosocial well-being (β 0.482, p 0.000). the relations among the variables spiritual transcendence, vulnerability to alcohol consumption and psychosocial well-being, based on Reed's Theory, are confirmed in the population group of young college students, concluding that psychosocial well-being can be achieved when spiritual transcendence is enhanced, as the vulnerability to alcohol consumption drops. demonstrar as relações entre vulnerabilidade, autotranscendência e bem-estar na população adulta jovem e o efeito de cada uma destas variáveis na adoção de condutas de baixo risco de consumo. estudo quantitativo, transversal do tipo correlacional que utilizou a análise estatística de Equações Estruturais para comprovar a relação entre as variáveis. evidenciou-se uma relação inversa entre a vulnerabilidade ao consumo do álcool e a transcendência espiritual (β-0.123, p 0.025) e uma relação direta positiva entre a transcendência espiritual e o bem-estar psicossocial (β 0.482, p 0.000). Conclusões: as relações das variáveis transcendência espiritual, vulnerabilidade ao consumo do álcool e bem-estar psicossocial, fundamentadas na Teoria de Reed, são confirmadas no grupo populacional de jovens adultos universitários, concluindo que é possível alcançar o bem-estar psicossocial quando se incrementa a transcendência espiritual, enquanto a vulnerabilidade ao consumo do álcool se reduz. demostrar las relaciones entre vulnerabilidad, autotrascendencia y bienestar en la población adulta joven y el efecto de cada una de estas variables en la adopción de conductas de bajo riesgo de consumo. estudio de abordaje cuantitativo, trasversal de tipo correlacional que utilizó el análisis estadístico de Ecuaciones Estructurales para la comprobación de la relación entre las variables. se evidenció relación inversa entre la vulnerabilidad al consumo de alcohol y la trascendencia espiritual (β-0.123, p 0.025) y una relación directa positiva entre la trascendencia espiritual y el bienestar psicosocial (β 0.482, p 0.000). las relaciones de las variables trascendencia espiritual, vulnerabilidad al consumo de alcohol y bienestar psicosocial, fundamentadas en la Teoría de Reed, son confirmadas en el grupo poblacional de adultos jóvenes universitarios, concluyendo que es posible alcanzar el bienestar psicosocial cuando se incrementa la trascendencia espiritual, en tanto que la vulnerabilidad al consumo de alcohol se reduce.

PubMed

Hernández Mosqueira, Claudio; Hernández Vasquez, Dagoberto; Caniuqueo Vargas, Alexis; Castillo Quezada, Humberto; Fernandes Da Silva, Sandro; Pavez-Adasme, Gustavo; Martínez Salazar, Cristian; Cárcamo-Oyarzún, Jaime; Fernandes Filho, José

2016-11-29

Introducción: Chile en las últimas décadas ha experimentado un cambio en su perfil epidemiológico nutricional, pasando de una situación caracterizada por una elevada prevalencia de desnutrición y enfermedades infecciosas/parasitarias a otro completamente distinto, en donde las enfermedades crónicas y degenerativas presentan una elevada prevalencia.Objetivo: el objetivo del estudio es elaborar tablas de referencia de aspectos antropométricos y de condición física en estudiantes varones de 10 a 14 años de la ciudad de Chillán.Método: estudio descriptivo de corte transversal. La muestra se compone de 1250 varones con edades entre los 10 y 14 años. Para la confección de las tablas de referencia se utilizó estadística descriptiva y estas fueron divididas en cinco clasificaciones desde muy malo, malo, media, bueno y muy bueno, teniendo como parámetro la edad.Resultados: observamos niveles importantes de sobrepeso que se asociaron con bajo desempeño físico, lo que plantea la urgencia de realizar un seguimiento en el tiempo con herramientas de fácil aplicación como la presente batería; con el fin de detectar a tiempo a los niños que tienen bajos niveles de condición física y tomar medidas orientadas a estimular o mejorar la capacidad física como factores protectores de promoción de la salud y como ayuda en la prevención de enfermedades crónicas relacionadas con el sobrepeso u obesidad.Conclusión: en este trabajo se han establecido valores de referencia para posteriores estudios en cuanto a la condición física orientada a la salud en estudiantes varones de 10 a 14 años de la ciudad de Chillán, que permitirán evaluar e interpretar correctamente la condición física orientada a la salud de este grupo etario.

[Not Available].

PubMed

Chivu, Elena Cristina; Artero-Fullana, Ana; Alfonso García, Antonio; Sánchez Juan, Carlos

2016-07-19

Introducción: conociendo la elevada prevalencia de la desnutrición hospitalaria, se hace necesaria su detección precoz. Cuando, por diversos motivos, no es posible realizar una valoración completa del estado nutricional, se recomienda el empleo de herramientas validadas de cribado nutricional. Estas ayudarían a detectar de forma rápida a aquellos pacientes que necesiten de un tratamiento nutricional.Objetivos: determinar la prevalencia del riesgo de desnutrición, en el Hospital General Universitario de Valencia, empleando para ello la herramienta de cribado nutricional HEMAN y comprobar si la implementación de esta herramienta en la práctica clínica, sería lo más adecuado.Métodos: estudio transversal, realizado sobre una muestra de 1.099 pacientes ingresados en un hospital terciario. A todos ellos se les realizó el cribado nutricional HEMAN a las 24-48 horas del ingreso. Las variables cualitativas se compararon mediante Chi-cuadrado, y las cuantitativas mediante el test t de Student.Resultados: la prevalencia del riesgo de desnutrición fue del 33,5%. Los pacientes que resultaron positivos en el cribado (HEMAN ≥ 3), tenían mayor edad que los pacientes normonutridos, referían pérdidas de peso entre el 5-10%, el 55,2% disminuyó su ingesta a menos del 50% de la habitual. Además, ingresaron con patologías consideradas de leves a moderadas. La utilización del método HEMAN como herramienta de cribado, resultó ser práctica y efectiva, y ayudó a disminuir el tiempo empleado con cada paciente encuestado evaluado.Conclusiones: se detectó una elevada prevalencia de riesgo de desnutrición entre los pacientes evaluados, por lo tanto se hace imprescindible la utilización de métodos de cribado nutricional en la rutina diaria del hospital, para ello recomendamos especialmente la utilización del método HEMAN.

[Not Available].

PubMed

Molina Villaverde, Raquel

2016-06-03

El cáncer es un problema sanitario de primera magnitud a escala mundial. Su tratamiento es uno de los mayores campos de innovación y desarrollo en medicina. La visión del cáncer como una enfermedad sistémica, heterogénea y de una elevada complejidad hace que los enfermos deban recibir una atención oncológica de calidad, proporcionada por equipos multidisciplinares altamente cualificados. Además de la gran incidencia de malnutrición en estos pacientes, la intervención nutricional precoz puede mejorar su pronóstico, aumentar la calidad de vida y disminuir la tasa de complicaciones de la enfermedad. Por ello, es necesaria una estrecha colaboración entre el oncólogo y el experto en nutrición.

Silver segregation in Ag/a-C nanocomposite coatings for potential application as antibacterial surfaces

NASA Astrophysics Data System (ADS)

Manninen, Noora Kristiina Alves de Sousa

O desenvolvimento de superficies antibacterianas representa um desafio atual em diferentes aplicacoes industriais, nomeadamente, dispositivos medicos, embalagens alimentares, texteis e sistemas de tratamento de agua. A maioria das bacterias existe em biofilmes que aderem fortemente a diferentes tipos de superficies uma vez que esta adesao representa um mecanismo estrategico de sobrevivencia. O fenomeno da adesao e colonizacao microbiana resulta na falha de diferentes dispositivos e componentes utilizados nas aplicacoes acima mencionadas, tendo como consequencia perdas economicas elevadas e representando tambem um problema de saude publica quando se tratam de aplicacoes como dispositivos medicos ou embalagens alimentares. Neste sentido, ao longo das ultimas decadas o desenvolvimento de superficies antibacterianas tem sido considerada uma estrategia emergente no desenvolvimento de materiais mais eficientes a serem aplicados em diferentes sectores. O objetivo da presente tese consiste no desenvolvimento e caracterizacao de revestimentos nanocompositos multifuncionais baseados em revestimentos de carbono amorfo dopado com nanoparticulas de prata (Ag/a-C) para potencial aplicacao em superficies antibacterianas. A Ag e atualmente considerada como o agente bactericida mais promissor e eficiente, sendo que as nanoparticulas de prata representam o material mais comercializado na area da nanotecnologia. A estrategia de modificacao superficial com revestimentos baseados em carbono amorfo (a-C) tem-se tornado popular do ponto de vista industrial essencialmente, devido entre outras propriedades, a sua resistencia ao desgaste tribologico excecional, que permite combinar uma elevada dureza com um baixo coeficiente de atrito, elevada estabilidade quimica, resistencia a corrosao e biocompatibilidade em diferentes aplicacoes biomedicas. Na atualidade os revestimentos de a-C sao utilizados em diferentes aplicacoes industriais nomeadamente dispositivos medicos, laminas de barbear e diferentes componentes mecanicos sujeitos a elevado desgaste tribologico. Neste sentido, a combinacao das propriedades intrinsecas destes materiais pode ser considerada uma abordagem promissora para o desenvolvimento de revestimentos multifuncionais, os quais podem ser aplicados em diferentes produtos, nomeadamente, dispositivos medicos. Na presente tese os revestimentos nanocompositos de Ag/a-C sao depositados por dois metodos distintos: (i) pulverizacao catodica em magnetrao e (ii) combinacao da pulverizacao catodica em magnetrao para deposicao da camada de a-C e condensacao em atmosfera inerte para a incorporacao simultanea de nanoparticulas de Ag na matrix de carbono. Os metodos acima mencionados sao comparados em relacao a uniformidade dos revestimentos depositados, permitindo efetuar a escolha do metodo de deposicao mais eficaz (pulverizacao catodica em magnetrao). Os revestimentos nanocompositos de Ag/a-C sao caraterizados relativamente a sua estrutura, estabilidade termodinamica em condicoes ambientais e propriedades funcionais (comportamento tribologico e atividade antibacteriana). O trabalho central da tese e focado na caraterizacao de revestimentos Ag/a-C contendo 20% at. de Ag, com diferentes espessuras e diferentes estruturas em multicamada. Os resultados sugerem que os revestimentos Ag/a-C sao instaveis mesmo em condicoes ambientais, sendo observado que a Ag e forma nanofibras entre as fronteiras das colunas, as quais recobrem a superficie do revestimento poucas semanas apos a producao. O processo de formacao de nanofibras e promovido pela humidade, sendo que, as particulas crescem atraves de um processo de coalescencia. As propriedades funcionais sugerem que os revestimentos Ag/a-C sao promissores do ponto de vista de actividade antibacteriana, a qual esta relacionada com a sua ionizacao. Os testes tribologicos revelam que em ambiente nao lubrificado a presenca da Ag promove a degradacao dos revestimentos a-C, contudo, em meios biologicos que simulam o liquido sinovial, presente nas articulacoes da anca, o comportamento tribologico e semelhante aos revestimentos a-C.

New tools for subsurface imaging of 3D seismic Node data in hydrocarbon exploration =

NASA Astrophysics Data System (ADS)

Benazzouz, Omar

A aquisicao de dados sismicos de reflexao multicanal 3D/4D usando Ocean Bottom NODES de 4 componentes constitui atualmente um sector de importancia crescente no mercado da aquisicao de dados reflexao sismica marinha na industria petrolifera. Este tipo de dados permite obter imagens de sub-superficie de alta qualidade, com baixos niveis de ruido, banda larga, boa iluminacao azimutal, offsets longos, elevada resolucao e aquisicao de tanto ondas P como S. A aquisicao de dados e altamente repetitiva e portanto ideal para campanhas 4D. No entanto, existem diferencas significativas na geometria de aquisicao e amostragem do campo de ondas relativamente aos metodos convencionais com streamers rebocados a superficie, pelo que e necessario desenvolver de novas ferramentas para o processamento deste tipo de dados. Esta tese investiga tres aspectos do processamento de dados de OBSs/NODES ainda nao totalmente resolvidos de forma satisfatoria: a deriva aleatoria dos relogios internos, o posicionamento de precisao dos OBSs e a implementacao de algoritmos de migracao prestack 3D em profundidade eficientes para obtencao de imagens precisas de subsuperficie. Foram desenvolvidos novos procedimentos para resolver estas situacoes, que foram aplicados a dados sinteticos e a dados reais. Foi desenvolvido um novo metodo para deteccao e correccao de deriva aleatoria dos relogios internos, usando derivadas de ordem elevada. Foi ainda desenvolvido um novo metodo de posicionamento de precisao de OBSs usando multilateracao e foram criadas ferramentas de interpolacao/extrapolacao dos modelos de velocidades 3D de forma a cobrirem a extensao total area de aquisicao. Foram implementados algoritmos robustos de filtragem para preparar o campo de velocidades para o tracado de raios e minimizar os artefactos na migracao Krichhoff pre-stack 3D em profundidade. Os resultados obtidos mostram um melhoramento significativo em todas as situacoes analisadas. Foi desenvolvido o software necessario para o efeito e criadas solucoes computacionais eficientes. As solucoes computacionais desenvolvidas foram integradas num software standard de processamento de sismica (SPW) utilizado na industria, de forma a criar, conjuntamente com as ferramentas ja existentes, um workflow de processamento integrado para dados de OBS/NODES, desde a aquisicao e controle de qualidade a producao dos volumes sismicos migrados pre-stack em profundidade.

Charge Effect on the Formation of Polyoxometalate-Based Supramolecular Polygons Driven by Metal Coordination.

PubMed

Piot, Madeleine; Hupin, Sébastien; Lavanant, Hélène; Afonso, Carlos; Bouteiller, Laurent; Proust, Anna; Izzet, Guillaume

2017-07-17

The metal-driven self-assembly of a Keggin-based hybrid bearing two remote pyridine units was investigated. The resulting supramolecular species were identified by combination of 2D diffusion NMR spectroscopy (DOSY) and electrospray ionization mass spectrometry (ESI-MS) as a mixture of molecular triangles and squares. This behavior is different from that of the structural analogue Dawson-based hybrid displaying a higher charge, which only led to the formation of molecular triangles. This study highlights the decisive effect of the charge of the POMs in their self-assembly processes that disfavors the formation of large assemblies. An isothermal titration calorimetry (ITC) experiment confirmed the stronger binding in the case of the Keggin hybrids. A correlation between the diffusion coefficient D and the molecular mass M of the POM-based building block and its coordination oligomers was also observed. We show that the diffusion coefficient of these compounds is mainly determined by their occupied volume rather than by their shape.

Self-reporting and refoldable profluorescent single-chain nanoparticles.

PubMed

Fischer, Tobias S; Spann, Sebastian; An, Qi; Luy, Burkhard; Tsotsalas, Manuel; Blinco, James P; Mutlu, Hatice; Barner-Kowollik, Christopher

2018-05-28

We pioneer the formation of self-reporting and refoldable profluorescent single-chain nanoparticles (SCNPs) via the light-induced reaction ( λ max = 320 nm) of nitroxide radicals with a photo-active crosslinker. Whereas the tethered nitroxide moiety in these polymers fully quenches the luminescence ( i.e. fluorescence) of the aromatic backbone, nitroxide trapping of a transient C-radical leads to the corresponding closed shell alkoxyamine thereby restoring luminescence of the folded SCNP. Hence, the polymer in the folded state is capable of emitting light, while in the non-folded state the luminescence is silenced. Under oxidative conditions the initially folded SCNPs unfold, resulting in luminescence switch-off and the reestablishment of the initial precursor polymer. Critically, we show that the luminescence can be repeatedly silenced and reactivated. Importantly, the self-reporting character of the SCNPs was followed by size-exclusion chromatography (SEC), dynamic light scattering (DLS), fluorescence, electron paramagnetic resonance (EPR), nuclear magnetic resonance (NMR) and diffusion ordered NMR spectroscopy (DOSY).

NMR Techniques in Metabolomic Studies: A Quick Overview on Examples of Utilization.

PubMed

Kruk, Joanna; Doskocz, Marek; Jodłowska, Elżbieta; Zacharzewska, Anna; Łakomiec, Joanna; Czaja, Kornelia; Kujawski, Jacek

2017-01-01

Metabolomics is a rapidly developing branch of science that concentrates on identifying biologically active molecules with potential biomarker properties. To define the best biomarkers for diseases, metabolomics uses both models (in vitro, animals) and human, as well as, various techniques such as mass spectroscopy, gas chromatography, liquid chromatography, infrared and UV-VIS spectroscopy and nuclear magnetic resonance. The last one takes advantage of the magnetic properties of certain nuclei, such as 1 H, 13 C, 31 P, 19 F, especially their ability to absorb and emit energy, what is crucial for analyzing samples. Among many spectroscopic NMR techniques not only one-dimensional (1D) techniques are known, but for many years two-dimensional (2D, for example, COSY, DOSY, JRES, HETCORE, HMQS), three-dimensional (3D, DART-MS, HRMAS, HSQC, HMBC) and solid-state NMR have been used. In this paper, authors taking apart fundamental division of nuclear magnetic resonance techniques intend to shown their wide application in metabolomic studies, especially in identifying biomarkers.

[Studies on usefullness of imidasol preparations for treatment of pulmonary and air sacks aspergillosis in geese].

PubMed

Ramisz, A; Balicka-Ramisz, A

2001-01-01

The studies were carried out in two geese farms with a total number of 11.143 - 4 weeks old birds. Two imidazol preparations--5 per cent Miconazole powder and 2 Clotrimazole solution were used in these studies. Miconazole was applied as feed additive for 200 with aspergillosis infected geese, in a dosis of 10 mg of active substance on one kg of body weight. Clotrimazole was administered in a form of inhalation in a dose of 1,5 1 of 2 per cent solution per geese house of 3000 m3. Spraying was performed using gas-pipes of steam ganerator joined to the air compressor of the type 3 JW - 60 (6hp). In this way 5 - 10 microm partiches were obtained. The preparation was sprayed twice ad 2 - 4 days intervals. After Miconazole administration the recovery of sick birds and inhibition of the disease in geese were observed. The Clotrimazole preparations may be also administered prophylactically in geese houses, were stationary aspergillosis has been observed.

Small Molecule Activation by Intermolecular Zr(IV)-Phosphine Frustrated Lewis Pairs.

PubMed

Metters, Owen J; Forrest, Sebastian J K; Sparkes, Hazel A; Manners, Ian; Wass, Duncan F

2016-02-17

We report intermolecular transition metal frustrated Lewis pairs (FLPs) based on zirconocene aryloxide and phosphine moieties that exhibit a broad range of small molecule activation chemistry that has previously been the preserve of only intramolecular pairs. Reactions with D2, CO2, THF, and PhCCH are reported. By contrast with previous intramolecular examples, these systems allow facile access to a variety of steric and electronic characteristics at the Lewis acidic and Lewis basic components, with the three-step syntheses of 10 new intermolecular transition metal FLPs being reported. Systematic variation to the phosphine Lewis base is used to unravel steric considerations, with the surprising conclusion that phosphines with relatively small Tolman steric parameters not only give highly reactive FLPs but are often seen to have the highest selectivity for the desired product. DOSY NMR spectroscopic studies on these systems reveal for the first time the nature of the Lewis acid/Lewis base interactions in transition metal FLPs of this type.

[AMEBIOSIS

PubMed

Náquira C, César

1997-01-01

This is a short review of the infection and disease caused by Entamoeba histolytica. The morphology of the evolutive stages and the life cycle of the parasite is described, including biochemical and immunological data.The intestinal and extraintestinal forms of this disease are briefly characterized as well as the diagnosis by images and laboratory. Differentiation between E. histolytica and E. dispar (known as nonpathogenic E. histolytica) with similar morphology is crucial for individual or mass treatment.This treatment is dealing with the better known drugs and their recommended dosis. The infection by E. histolytica/E. dispar is widely distributed in Peru with variable rates of prevalence (1 to 28%), according with the applied methodology, and the studied population. Recently, the presence of both amoebas has been confirmed by biochemical characterization, and their real prevalence must be determined. The profilaxis and control of this parasitism is based in avoiding fecalism. Sanitary education, environmental sanitation, and mass treatment of risk groups would be the most important measures against ameblasis.

Determination of the presence of hyaluronic acid in preparations containing amino acids: the molecular weight characterization.

PubMed

Bellomaria, A; Nepravishta, R; Mazzanti, U; Marchetti, M; Piccioli, P; Paci, M

2014-10-15

Several pharmaceutical preparations contain hyaluronic acid in the presence of a large variety of low molecular weight charged molecules like amino acids. In these mixtures, it is particularly difficult to determine the concentration and the molecular weight of the hyaluronic acid fragments. In fact zwitterionic compounds in high concentration behave by masking the hyaluronic acid due to the electrostatic interactions between amino acids and hyaluronic acid. In such conditions the common colorimetric test of the hyaluronic acid determination appears ineffective and in the (1)H NMR spectra the peaks of the polymer disappear completely. By a simple separation procedure the presence of hyaluronic acid was revealed by the DMAB test and (1)H NMR while its average molecular weight in the final product was determined by DOSY NMR spectroscopy alone. The latter determination is very important due to the healthy effects of some sizes of this polymer's fragments. Copyright © 2014 Elsevier B.V. All rights reserved.

Synergistic mutual potentiation of antifungal activity of Zuccagnia punctata Cav. and Larrea nitida Cav. extracts in clinical isolates of Candida albicans and Candida glabrata.

PubMed

Butassi, Estefanía; Svetaz, Laura A; Ivancovich, Juan J; Feresin, Gabriela E; Tapia, Alejandro; Zacchino, Susana A

2015-06-01

Zuccagnia punctata Cav. (Fabaceae) and Larrea nitida Cav. (Zygophyllaceae) are indistinctly or jointly used in traditional medicine for the treatment of fungal-related infections. Although their dichloromethane (DCM) extract have demonstrated moderate antifungal activities when tested on their own, antifungal properties of combinations of both plants have not been assessed previously. The aim of this study was to establish with statistical rigor whether Z. punctata (ZpE) and L. nitida DCM extract (LnE) interact synergistically against the clinically important fungi Candida albicans and Candida glabrata and to characterize the most synergistic combinations. For synergism assessment, the statistical-based Boik's design was applied. Eight ZpE-LnE fixed-ratio mixtures were prepared from four different months of 1 year and tested against Candida strains. Lϕ (Loewe index) of each mixture at different fractions affected (ϕ) allowed for the finding of the most synergistic combinations, which were characterized by HPLC fingerprint and by the quantitation of the selected marker compounds. Lϕ and confidence intervals were determined in vitro with the MixLow method, once the estimated parameters from the dose-response curves of independent extracts and mixtures, were obtained. Markers (four flavonoids for ZpE and three lignans for LnE) were quantified in each extract and their combinations, with a valid HPLC-UV method. The 3D-HPLC profiles of the most synergistic mixtures were obtained by HPLC-DAD. Three over four IC50ZpE/IC50LnE fixed-ratio mixtures displayed synergistic interactions at effect levels ϕ > 0.5 against C. albicans. The dosis of the most synergistic (Lϕ = 0.62) mixture was 65.96 µg/ml (ZpE = 28%; LnE = 72%) containing 8 and 36% of flavonoids and lignans respectively. On the other hand, one over four IC50ZpE/IC50LnE mixtures displays synergistic interactions at ϕ > 0.5 against C. glabrata. The dosis of the most synergistic (Lϕ = 0.67) mixture was 168.23 µg/ml (ZpE = 27%; LnE = 73%) with 9.7 and 31.6% of flavonoids and lignans respectively. Studies with the statistical-based MixLow method, allowed for the finding of the most ZpE-LnE synergistic mixtures, giving support to a proper joint use of both antifungal herbs in traditional medicine. Copyright © 2015 Elsevier GmbH. All rights reserved.

Agricultural contaminants in Quaternary aquitards: A review of occurrence and fate in North America

NASA Astrophysics Data System (ADS)

Rodvang, S. J.; Simpkins, W. W.

2001-01-01

The intensity of agriculture has increased significantly during the past 30 years, resulting in increased detection of agricultural contaminants (nutrients, pesticides, salts, trace elements, and pathogens) in groundwater. Till, glaciolacustrine, and loess deposits of Quaternary age compose the most common surficial deposits underlying agricultural areas in North America. Quaternary aquitards generally contain higher concentrations of solid organic carbon (SOC, as much as 1.4%), dissolved organic carbon (DOC, as much as 205 mg/L), and reduced sulfur (as much as 0.9%) than do aquifers. Their potential to sorb pesticides increases with the percent of older SOC, because diagenesis increases Koc. Denitrification consistently reduces nitrate to non-detectable levels in unweathered Quaternary aquitards. Organic carbon of Quaternary age is a more labile electron donor than carbon from shale clasts. Pyrite is a more labile electron donor than carbon in many instances. Unweathered Quaternary aquitards provide a high degree of protection for underlying aquifers, due to their large reserves of SOC and reduced sulfur for sorption and denitrification, combined with their typically low hydraulic conductivity. In contrast, agricultural contaminants are common in weathered Quaternary aquitards. Lower reserves of reduced sulfur and sorptive/labile organic carbon, and a higher bulk K due to fractures, limit their ability to attenuate nitrate and pesticides. Subsurface drainage, which is common in Quaternary aquitards because of high water tables, bypasses the attenuation capacity of Quaternary aquitards and facilitates the transport of agricultural contaminants to surface water. Résumé. L'agriculture s'est significativement accrue au cours des dernières 30 années, provoquant une détection plus fréquente dans les eaux souterraines de contaminants agricoles (engrais, pesticides, sels, éléments en traces et germes pathogènes). Les moraines, les formations glacio-lacustres et les lœss d'âge quaternaire sont les dépôts superficiels les plus courants sur lesquels sont implantées les régions agricoles d'Amérique du Nord. Les imperméables quaternaires contiennent généralement des concentrations en carbone organique particulaire (COP), jusqu'à 1,4%, en carbone organique dissous, jusqu'à 205 mg/L et en soufre réduit, jusqu'à 0,9%, plus élevées que dans les aquifères. Leur potentiel à adsorber les pesticides augmente en même temps que le pourcentage en COP plus ancien, parce que la diagenèse fait croître KOC. La dénitrification réduit logiquement les nitrates à des niveaux non détectables dans les imperméables quaternaires non altérés. Le carbone organique d'âge quaternaire est un donneur d'électrons plus labile que le carbone des débris schisteux. La pyrite est un donneur d'électrons plus labile que le carbone dans de nombreux cas. Les imperméables quaternaires non altérés constituent une protection très efficace pour les aquifères sous-jacents, du fait de leur importante réserve en COP et en soufre réduit, qui interviennent dans la sorption et la dénitrification, et du fait de leur conductivité hydraulique typiquement faible. Au contraire, les contaminants agricoles sont communs dans les imperméables quaternaires altérés. Leur plus faible réserve en soufre réduit et en carbone organique labile impliqué dans la sorption, ainsi qu'une conductivité globale plus forte due aux fractures, limite leur aptitude à atténuer les nitrates et les pesticides. Le drainage souterrain, qui est courant dans les imperméables quaternaires à cause des niveaux élevés des nappes, court-circuite la capacité d'atténuation des imperméables quaternaires et facilite le transport des contaminants agricoles vers les eaux de surface. Resúmen. La intensidad de la agricultura ha aumentado de forma significativa durante los últimos 30 años, provocando una afección creciente de contaminantes de origen agrícola (tales como nutrientes, pesticidas, sales, elementos traza y patógenos) en las aguas subterráneas. Los depósitos cuaternarios de till, de origen glaciolacustre y de loess constituyen la mayor parte de los terrenos aprovechados desde el punto de vista agrícola en Norteamérica. Los acuitardos cuaternarios contienen normalmente concentraciones más elevadas que los acuíferos en carbono orgánico sólido (COS, con hasta un 1,4%), carbono orgánico disuelto (COD, hasta 205 mg/L) y sulfuro reducido (hasta un 0,9%). Su potencial para absorber pesticidas aumenta con el porcentaje de COS más antiguo, ya que la diagénesis incrementa el coeficiente de partición, Koc. El nitrato se reduce por denitrificación hasta alcanzar valores no detectables en acuitardos cuanternarios no meteorizados. El carbono orgánico de la Edad Cuaternaria es un dador de electrones más lábil que el carbono presente en los clastos de esquisto. La pirita es un dador de electrones más lábil que el carbono en muchas circunstancias. Los acuitardos no meteorizados del Cuaternario proporcionan un alto grado de protección para los acuíferos subyacentes, puesto que tienen grandes reservas de COS y sulfuro reducido para sorción y denitrificación, además de conductividades hidráulicas normalmente bajas. Por el contrario, los contaminantes agrícolas son más habituales en acuitardos meteorizados del Cuaternario, donde la capacidad para atenuar nitratos y pesticidas se ve limitada por unas reservas menores de sulfuro reducido y de carbono orgánico sorbible/lábil, así como por la elevada conductividad hidráulica promedio debido a las fracturas. El drenaje subsuperficial, que es común en los acuitardos cuaternarios que tienen niveles freáticos altos, evita la capacidad de atenuación propia de dichos acuitardos y facilita el transporte de los contaminantes de origen agrícola hacia las aguas superficiales.

Microstructure design of titanate-based electroceramics =

NASA Astrophysics Data System (ADS)

Amaral, Luis Miguel de Almeida

Electrocerâmicos sao uma classe de materiais avancados com propriedades electricas valiosas para aplicacoes. Estas propriedades sao geralmente muito dependentes da microestrutura dos materiais. Portanto, o objectivo geral deste trabalho e investigar o desenho da resposta dielectrica de filmes espessos obtidos por Deposicao Electroforetica (EPD) e cerâmicos monoliticos, atraves do controlo da evolucao da microestrutura durante a sinterizacao de electrocerâmicos a base de titanatos. Aplicacoes sem fios na industria microelectronica e de comunicacoes, em rapido crescimento, tornaram-se um importante mercado para os fabricantes de semicondutores. Devido a constante necessidade de miniaturizacao, reducao de custos e maior funcionalidade e integracao, a tecnologia de filmes espessos esta a tornar-se uma abordagem de processamento de materiais funcionais cada vez mais importante. Uma tecnica adequada neste contexto e EPD. Os filmes espessos resultantes necessitam de um passo subsequente de sinterizacao que e afectada pelo substrato subjacente, tendo este um forte efeito sobre a evolucao da microestrutura. Relacionado com a miniaturizacao e a discriminacao do sinal, materiais dielectricos usados como componentes operando a frequencias das microondas em aplicacoes na industria microelectronica de comunicacoes devem apresentar baixas perdas dielectricas e elevadas permitividade dielectrica e estabilidade com a temperatura. Materiais do sistema BaO-Ln2O3- TiO2 (BLnT: Ln = La ou Nd), como BaLa4Ti4O15 (BLT) e Ba4.5Nd9Ti18O54 (BNT), cumprem esses requisitos e sao interessantes para aplicacoes, por exemplo, em estacoes de base para comunicacoes moveis ou em ressonadores para telefones moveis, onde a miniaturizacao dos dispositivos e muito importante. Por sua vez, o titanato de estroncio (SrTiO3, STO) e um ferroelectrico incipiente com constante dielectrica elevada e baixas perdas, que encontra aplicacao em, por exemplo, condensadores de camada interna, tirando partido de fronteiras de grao altamente resistivas. A dependencia da permitividade dielectrica do campo electrico aplicado torna este material muito interessante para aplicacoes em dispositivos de microondas sintonizaveis. Materiais a base de STO sao tambem interessantes para aplicacoes termoelectricas, que podem contribuir para a reducao da actual dependencia de combustiveis fosseis por meio da geracao de energia a partir de calor desaproveitado. No entanto, as mesmas fronteiras de grao resistivas sao um obstaculo relativamente a eficiencia do STO para aplicacoes termoelectricas. (Abstract shortened by ProQuest.).

Complexes between methyltestosterone and β-cyclodextrin for application in aquaculture production.

PubMed

Carvalho, Lucas Bragança de; Burusco, Kepa Koldo; Jaime, Carlos; Venâncio, Tiago; Carvalho, Aline Ferreira Souza de; Murgas, Luis David Solis; Pinto, Luciana de Matos Alves

2018-01-01

The inclusion complexes between 17-α-methyltestosterone (MT) and β-cyclodextrin (bCD) were prepared and characterized in dissolution and solid phase. The complex promoted a sixfold increment in solubility of the hormone. It has a limited solubility and stoichiometry of 2:1 (bCD:MT) determined by DSC, NMR and solubility experiments, the association constant Ka=2846Lmol -1 and complex fraction of 76% (assessed by DOSY-NMR, in (1:3) DMSO/D 2 O). The association constant obtained in water by the solubility isotherms is 7540Lmol -1 . 2D-ROESY experiments indicate the intermolecular orientation (complete inclusion of the hormone in the cavity). Simulations by molecular dynamics agreed with the formation of the inclusion complex 2:1. Release tests showed the slower release for the complexes, with 50% for lyophilization and 56% for malaxation. These results clearly demonstrate the complexation of MT in bCD, which formulations are promising for further applications involving this steroid in aquaculture, both for sexual reversal and in technologies of hormone in water sequestration. Copyright © 2017 Elsevier Ltd. All rights reserved.

Stimuli-responsive supramolecular micellar assemblies of cetylpyridinium chloride with cucurbit[5/7]urils.

PubMed

Choudhury, Sharmistha Dutta; Barooah, Nilotpal; Aswal, Vinod Kumar; Pal, Haridas; Bhasikuttan, Achikanath C; Mohanty, Jyotirmayee

2014-05-21

This article demonstrates, for the first time, construction of novel cucurbituril (CB)-adorned supramolecular micellar assemblies of a cationic surfactant, cetylpyridinium chloride (CPC), through noncovalent host-guest interactions. The distinct cation receptor features and cavity dimensions of the CB5 and CB7 homologues assert that the macrocyclic hosts remain complexed with the CPC monomers and take part in the micelle formation, a unique observation in contrast to that of the classical host, β-cyclodextrin. The cooperative contributions of the CB macrocycles in the micelle formation have been documented by the photochemical, surface tension, conductivity, DOSY NMR, and SANS measurements. The contrasting downward and upward shifts in the cmc of the CPC surfactant, respectively, with CB5 and CB7 hosts provide a unique opportunity for the controlled tuning of the micellization region for CPC from 0.57 to 1.6 mM, by using a combination of the macrocyclic hosts. The article also establishes the reversible response of these soft supramolecular micellar structures to thermal-stimuli, which projects their utility for on-demand smart drug-delivery vehicles.

Surface characterization of hydrophobic core-shell QDs using NMR techniques

NASA Astrophysics Data System (ADS)

Zhang, Chengqi; Zeng, Birong; Palui, Goutam; Mattoussi, Hedi

2018-02-01

Using a few solution phase NMR spectroscopy techniques, including 1H NMR and 31P NMR, we have characterized the organic shell on CdSe-ZnS core-shell quantum dots and tracked changes in its composition when the QD dispersions are subjected to varying degrees of purification. Combining solution phase NMR with diffusion ordered spectroscopy (DOSY), we were able to distinguish between freely diffusing ligands in the sample from those bound on the surfaces. Additionally, matrix assisted laser desorption ionization (MALDI) and FTIR measurements were used to provide complementary and supporting information on the organic ligand coating for these nanocrystals. We found that the organic shell is dominated by monomeric or oligomeric n-hexylphosphonic acid (HPA), along with small portion of 1-hexadecyl amine (HDA). The presence of TOP/TOPO (tri-n-octylphosphine / tri-noctylphosphine oxide) molecules is much smaller, even though large excess of TOP/TOPO were used during the QD growth. These results indicate that HPA (alkyl phosphonate) exhibits the strongest coordination affinity to ZnS-rich QD surfaces grown using the high temperature injection route.

Metallosupramolecular Architectures Formed with Ferrocene-Linked Bis-Bidentate Ligands: Synthesis, Structures, and Electrochemical Studies.

PubMed

Findlay, James A; McAdam, C John; Sutton, Joshua J; Preston, Dan; Gordon, Keith C; Crowley, James D

2018-04-02

The self-assembly of ligands of different geometries with metal ions gives rise to metallosupramolecular architectures of differing structural types. The rotational flexibility of ferrocene allows for conformational diversity, and, as such, self-assembly processes with 1,1'-disubstituted ferrocene ligands could lead to a variety of interesting architectures. Herein, we report a small family of three bis-bidentate 1,1'-disubstituted ferrocene ligands, functionalized with either 2,2'-bipyridine or 2-pyridyl-1,2,3-triazole chelating units. The self-assembly of these ligands with the (usually) four-coordinate, diamagnetic metal ions Cu(I), Ag(I), and Pd(II) was examined using a range of techniques including 1 H and DOSY NMR spectroscopies, high-resolution electrospray ionization mass spectrometry, X-ray crystallography, and density functional theory calculations. Additionally, the electrochemical properties of these redox-active metallosupramolecular assemblies were examined using cyclic voltammetry and differential pulse voltammetry. The copper(I) complexes of the 1,1'-disubstituted ferrocene ligands were found to be coordination polymers, while the silver(I) and palladium(II) complexes formed discrete [1 + 1] or [2 + 2] metallomacrocyclic architectures.

Elevated Heart Rate is Associated with Cardiac Denervation in Patients with Heart Failure: A 123-Iodine-MIBG Myocardial Scintigraphy Study.

PubMed

Villacorta, Aline Sterque; Villacorta, Humberto; Souza, Jenne Serrão de; Teixeira, José Antônio Caldas; Muradas, Maria Clara S S S; Alves, Christiane Rodrigues; Precht, Bernardo Campanário; Porto, Pilar; Ubaldo, Letícia; Mesquita, Cláudio Tinoco; Nóbrega, Antônio Cláudio Lucas da

2016-11-01

In the Systolic Heart Failure Treatment With the If Inhibitor Ivabradine Trial (SHIFT), heart rate (HR) reduction with ivabradine was associated with improved survival and reduced hospitalizations in patients with heart failure (HF). The mechanisms by which elevated HR increases mortality are not fully understood. To assess the relationship of baseline HR with clinical, neurohormonal and cardiac sympathetic activity in patients with chronic HF and elevated HR. Patients with chronic HF who were in sinus rhythm and had resting HR>70 bpm despite optimal medical treatment were included in a randomized, double-blind study comparing ivabradine versus pyridostigmine. This report refers to the baseline data of 16 initial patients. Baseline HR (before randomization to one of the drugs) was assessed, and patients were classified into two groups, with HR below or above mean values. Cardiac sympathetic activity was assessed by 123-iodine-metaiodobenzylguanidine myocardial scintigraphy. Mean HR was 83.5±11.5 bpm (range 72 to 104), and seven (43.7%) patients had HR above the mean. These patients had lower 6-min walk distance (292.3±93 vs 465.2±97.1 m, p=0.0029), higher values of N-Terminal-proBNP (median 708.4 vs 76.1, p=0.035) and lower late heart/mediastinum rate, indicating cardiac denervation (1.48±0.12 vs 1.74±0.09, p<0.001). Elevated resting HR in patients with HF under optimal medical treatment was associated with cardiac denervation, worse functional capacity, and neurohormonal activation. No SHIFT (Systolic Heart Failure Treatment With the If Inhibitor Ivabradine Trial, ou Estudo do Tratamento da Insuficiência Cardíaca Sistólica com o Inibidor de If Ivabradina), a redução da frequência cardíaca (FC) com ivabradina associou-se com melhor sobrevida e redução das hospitalizações em pacientes com insuficiência cardíaca (IC). Os mecanismos pelos quais a FC elevada aumenta a mortalidade não são totalmente compreendidos. Avaliar a relação da FC basal com atividade clínica, neuro-hormonal e simpática cardíaca em pacientes com IC crônica e FC elevada. Pacientes com IC crônica em ritmo sinusal e FC≥70 apesar de tratamento adequado foram incluídos em um estudo duplo-cego, randomizado, que comparou ivabradina com piridostigmina. Este artigo refere-se a dados basais dos primeiros 16 pacientes. A FC basal (antes da randomização para um dos medicamentos) foi avaliada, e os pacientes classificados em dois grupos, com FC abaixo ou acima dos valores médios. A atividade simpática cardíaca foi avaliada por cintilografia com metaiodobenzilguanidina marcada com iodo 123. A FC média foi 83,5±11,5 bpm (intervalo 72 a 104), e sete pacientes (43.7%) tinham FC acima da média. Esses pacientes apresentaram menor distância percorrida no teste de caminhada de 6 minutos (292,3±93 vs 465,2±97,1 m, p=0,0029), valores mais altos de N-terminal do pró-BNP (mediana 708,4 vs 76,1, p=0,035) e menor relação coração/mediastino tardia, indicando desnervação cardíaca (1,48±0,12 vs 1,74±0,09, p<0,001). A FC de repouso elevada em pacientes com IC em tratamento médico adequado associou-se com desnervação cardíaca, pior capacidade funcional e ativação neuro-hormonal.

Determinants of tobacco use by students.

PubMed

Vargas, Lorena Silva; Lucchese, Roselma; Silva, Andrécia Cósmem da; Guimarães, Rafael Alves; Vera, Ivânia; Castro, Paulo Alexandre de

2017-05-04

Estimate the prevalence and determinants of tobacco use by students. This cross-sectional study, carried out between 2013 and 2014, evaluates 701 public school students between 10 and 79 years of age living in a city in the countryside of the State of Goias, Midwest of Brazil. A structured questionnaire collected the data and the predictor variables were demographic data, family nucleus, religion, physical activity practice, family functionality and parental smoking. Two multivariable models were implemented, the first for occasional tobacco use and the second for regular use, acquiring the measure of prevalence ratio (PR) and their respective 95%CI. Variables with p < 0.10 were included in Poisson regression models with robust variance to obtain the adjusted PR (adPR) and 95%CI. The Wald Chi-Squared test examined the differences between proportions, and values with p < 0.05 were statistically significant. The prevalence of occasional and regular tobacco use were 33.4% (95%CI 29.8-36.9) and 6.7% (95%CI 5.0-8.8), respectively. The factors associated with occasional tobacco consumption were age of 15 to 17 years (adPR = 1.98) and above 18 years (adPR = 3.87), male gender (adPR = 1.23), moderate family dysfunction (adPR = 1.30), high family dysfunction (adPR = 1.97) and parental smoking (adPR = 1.60). In regards to regular consumption of tobacco, age above 18 years (adPR = 4.63), lack of religion (adPR = 2.08), high family dysfunction (adPR = 2.35) and parental smoking (adPR = 2.89) remained associated. Students exhibit a high prevalence of occasional and regular tobacco use. This consumption relates to sociodemographic variables and family dysfunction. Estimar a prevalência e determinantes do consumo de tabaco por estudantes. Neste estudo de corte transversal, realizado entre 2013 e 2014, avaliamos 701 estudantes entre 10 e 79 anos de escolas públicas de um município do interior do estado de Goiás, Centro-Oeste do Brasil. Os dados foram coletados por meio de um questionário estruturado, cujas variáveis preditoras foram: dados sociodemográficos, núcleo familiar, religião, prática de atividade física, funcionalidade familiar e pai ou mãe fumante. Foram implementados dois modelos multivariáveis, o primeiro para uso de tabaco na vida e o segundo para uso regular, obtendo-se como medida de efeito razão de prevalência (RP) e seus respectivos IC95%. Variáveis com p < 0,10 foram incluídas em modelos de regressão de Poisson com variância robusta, para obtenção da RP ajustada (RPaj) e IC95%. O teste Qui-quadrado de Wald foi utilizado para testar as diferenças entre as proporções, e valores com p < 0,05 foram considerados estatisticamente significantes. As prevalências de consumo de tabaco na vida e regular foram de 33,4% (IC95% 29,8-36,9) e 6,7% (IC95% 5,0-8,8), respectivamente. Os fatores associados ao consumo de tabaco na vida foram: idade de 15 a 17 anos (RPaj = 1,98) e superior a 18 anos (RPaj = 3,87), sexo masculino (RPaj = 1,23), moderada disfuncionalidade familiar (RPaj = 1,30), elevada disfuncionalidade familiar (RPaj = 1,97) e pai ou mãe fumante (RPaj = 1,60). Em relação ao consumo regular de tabaco, permaneceram associados a idade superior a 18 anos (RPaj = 4,63), não possuir religião (RPaj = 2,08), elevada disfuncionalidade familiar (RPaj = 2,35) e pai ou mãe fumante (RPaj = 2,89). Estudantes apresentam elevada prevalência de consumo de tabaco na vida e regular. Esse consumo associa-se com variáveis sociodemográficas e disfuncionalidade familiar.

Lesiones subcutáneas dolorosas en paciente con melanoma metastásico: un caso de paniculitis linfocítica asociado a vemurafenib.

PubMed

Benavente-Villegas, Felipe; Ferrando-Roca, Francisco; Dolz-Gaitón, Raquel; Royo-Peiró, María

2017-10-15

Vemurafenib ha probado ser una herramienta útil en el tratamiento de melanoma metastásico con mutación BRAF-V600E. Los efectos adversos incluyen artralgias, fatiga y toxicidad cutánea, siendo infrecuente la paniculitis. Presentamos el caso de una paciente de 43 años con melanoma metastásico que desarrolla lesiones subcutáneas dolorosas en miembros inferiores y superiores, asociadas a clínica sistémica después de 2 semanas de inicio de tratamiento con Vemurafenib + Cobimetinib. La histología demostró paniculitis linfocitaria septal y lobulillar. La paciente tuvo mala tolerancia al tratamiento anti diana a dosis plenas, requiriendo su ajuste, generando una corticodependencia para controlar sintomatología, y que finalmente obligó a la descontinuación de la terapia dirigida contra melanoma.  A la fecha, se han descrito 29 casos en la literatura de paniculitis asociada a vemurafenib, siendo la mayoría paniculitis neutrofílicas con adecuado control de sintomatología asociando antiinflamatorios no esteroidales y/o corticoides orales sin requerir en su mayoría modificación de la terapia contra melanoma; sin embargo hay que tener presente que pueden haber casos con mala evolución que obligan a la reducción de dosis de vemurafenib y descontinuar el tratamiento, como ha ocurrido en nuestro reporte.Vemurafenib has proven to be a useful tool in the treatment of metastatic melanoma with BRAF-V600E mutation. Adverse effects include arthralgia, fatigue, and skin toxicity; panniculitis is a rare complication. We present the case of a 43-year-old patient with metastatic melanoma who developed painful subcutaneous nodules of the lower and upper limbs and associated systemic clinical symptoms after 2 weeks of treatment with vemurafenib plus cobimetinib. Histology showed a septal and lobular lymphocytic panniculitis.The patient had poor tolerance of the full-dose treatment, requiring its adjustment. Systemic corticosteroids were required to control symptomatology, which finally forced the discontinuation of the medication.To date, 29 cases have been described in the literature of panniculitis associated with vemurafenib. Most of these have been neutrophilic panniculitis, but adequate control of symptoms is usually achieved with nonsteroidal anti-inflammatory drugs and/or oral corticosteroids without requiring modification of melanoma therapy. However, it must be borne in mind that there may be cases that force the reduction and discontinuation ofvemurafenib treatment. We believe that this histological variant of lymphocytic panniculitis and its poor response to decrease in vemurafenib makes this case unusual and instructive.

PubMed

Dipierri, José Edgardo; Bronberg, Rubén Adrian

2017-09-08

Debido al incremento de casos de microcefalia por virus Zika en Brasil el Ministerio de Salud de Argentina recomienda incrementar la vigilancia de esta malformación. A fin de profundizar el conocimiento del comportamiento epidemiológico de microcefalia en el país se analiza la mortalidad infantil por microcefalia entre 1998-2012. Los datos proceden de la Dirección de Estadísticas e Información de Salud (DEIS). Se calculó por provincias y regiones la tasa de mortalidad infantil por microcefalia (TMI-M) y se realizó un análisis de agrupamiento a nivel departamental. Las tasas más elevadas se observaron en las regiones y provincias del norte del país. La distribución espacial de la TMI-M guarda relación con las prevalencias de microcefalia en recién nacidos. Esta distribución se relaciona con la mayor pobreza y consanguinidad del norte de la Argentina, factores sinérgicos predisponentes de la ocurrencia de malformaciones congénitas en general y de microcefalia en particular.

Simulações Numéricas de Rotação Nuclear Cometária

NASA Astrophysics Data System (ADS)

Voelzke, M. R.; Winter, O. C.

1999-08-01

Este trabalho apresenta os resultados iniciais de simulações numéricas da evolução rotacional, de um núcleo cometário não esférico, ao longo de uma passagem periélica, levando-se em conta os torques devido a existência dos jatos de poeira e de gás. Inicialmente os autores apresentam um modelo simples (primeira aproximação), com somente um único jato na extremidade do semi-eixo maior, para compreender a variação positiva ou negativa que estas forças não gravitacionais exercem sobre o período de rotação cometário. Posteriormente incrementa-se o número de jatos, os quais são distribuídos ao longo da superfície cometária, para observar-se a contribuição dos efeitos provenientes dos torques originários da liberação da poeira e gás cometários, que provavelmente violará a suposição da livre precessão. Os estados rotacionais, sob torques induzidos devido à sublimação, dependem fortemente da localização das áreas ativas do núcleo. Os cometas P/Schwassmann-Wachmann 1, P/Tempel 2, P/Forbes e C/Meunier-Dupouy serão observados fotometricamente, pelos autores, no Laboratório Nacional de Astrofísica (LNA) ao longo de algumas noites consecutivas em abril, junho e julho de 1999. Estas observações serão comparadas com as simulações numéricas de rotação cometária.

A Tiered Analytical Approach for Investigating Poor Quality Emergency Contraceptives

PubMed Central

Monge, María Eugenia; Dwivedi, Prabha; Zhou, Manshui; Payne, Michael; Harris, Chris; House, Blaine; Juggins, Yvonne; Cizmarik, Peter; Newton, Paul N.; Fernández, Facundo M.; Jenkins, David

2014-01-01

Reproductive health has been deleteriously affected by poor quality medicines. Emergency contraceptive pills (ECPs) are an important birth control method that women can use after unprotected coitus for reducing the risk of pregnancy. In response to the detection of poor quality ECPs commercially available in the Peruvian market we developed a tiered multi-platform analytical strategy. In a survey to assess ECP medicine quality in Peru, 7 out of 25 different batches showed inadequate release of levonorgestrel by dissolution testing or improper amounts of active ingredient. One batch was found to contain a wrong active ingredient, with no detectable levonorgestrel. By combining ultrahigh performance liquid chromatography-ion mobility spectrometry-mass spectrometry (UHPLC-IMS-MS) and direct analysis in real time MS (DART-MS) the unknown compound was identified as the antibiotic sulfamethoxazole. Quantitation by UHPLC-triple quadrupole tandem MS (QqQ-MS/MS) indicated that the wrong ingredient was present in the ECP sample at levels which could have significant physiological effects. Further chemical characterization of the poor quality ECP samples included the identification of the excipients by 2D Diffusion-Ordered Nuclear Magnetic Resonance Spectroscopy (DOSY 1H NMR) indicating the presence of lactose and magnesium stearate. PMID:24748219

Efficient functionalization of alginate biomaterials.

PubMed

Dalheim, Marianne Ø; Vanacker, Julie; Najmi, Maryam A; Aachmann, Finn L; Strand, Berit L; Christensen, Bjørn E

2016-02-01

Peptide coupled alginates obtained by chemical functionalization of alginates are commonly used as scaffold materials for cells in regenerative medicine and tissue engineering. We here present an alternative to the commonly used carbodiimide chemistry, using partial periodate oxidation followed by reductive amination. High and precise degrees of substitution were obtained with high reproducibility, and without formation of by-products. A protocol was established using l-Tyrosine methyl ester as a model compound and the non-toxic pic-BH3 as the reducing agent. DOSY was used to indirectly verify covalent binding and the structure of the product was further elucidated using NMR spectroscopy. The coupling efficiency was to some extent dependent on alginate composition, being most efficient on mannuronan. Three different bioactive peptide sequences (GRGDYP, GRGDSP and KHIFSDDSSE) were coupled to 8% periodate oxidized alginate resulting in degrees of substitution between 3.9 and 6.9%. Cell adhesion studies of mouse myoblasts (C2C12) and human dental stem cells (RP89) to gels containing various amounts of GRGDSP coupled alginate demonstrated the bioactivity of the material where RP89 cells needed higher peptide concentrations to adhere. Copyright © 2015 Elsevier Ltd. All rights reserved.

Abnormal dendritic maturation of neurons under the influence of a Tilorone analogue (R 10.874).

PubMed

Pfau, D; Westphal, S; Bossanyi, P V; Dietzmann, K

1995-11-01

Tilorone analogue (R 10.874) has a close affinity to the lysosomal compartment of cells and forms a non degradable carbohydrate-lipid-drug complex accumulated within digesting organelles. Resembling biochemical and structural changes are seen in hereditary mucopolysaccharidoses accompanied with abnormal dendritogenesis. On the other hand, developmental toxicity (TERRY et al. 1992), antiproliferative effects (ALGARRA et al. 1993) and interactions with DNA (GELLER et al. 1985) are generated by tilorone. Therefore it should be interesting to know whether the amphiphilic cationic compound is able to produce an abnormal dendritogenesis as in storage diseases or an impaired arborisation of dendrites and what could be the reason for the misdevelopment. We demonstrate that there was a fetal retardation in the development of dendritic network, even under influence of low dosis of the analogue R 10.874. The dendritic dismaturation was concomitant with an increased amount of fatty acids and a slightly disarranged metabolic pathway of gangliosides. The dendritic arborisation closed the gap of retarded development between intrauterine treated and untreated rats after 7 days of postnatal drug elimination. We suppose that a fetotoxic effect and not the lysosomopathy is responsible for the reduced dendritic network.

Physicochemical Properties of α-Form Hydrated Crystalline Phase of 3-(10-Carboxydecyl)-1,1,1,3,5,5,5-heptamethyl Trisiloxane/Higher alcohol/Polyoxyethylene (5 mol) Glyceryl monostearate/Water System.

PubMed

Uyama, Makoto; Araki, Hidefumi; Fukuhara, Tadao; Watanabe, Kei

2018-06-07

The α-form hydrated crystalline phase (often called as an α-gel) is one of the hydrated crystalline phases which can be exhibited by surfactants and lipids. In this study, a novel system of an α-form hydrated crystal was developed, composed of 3-(10-carboxydecyl)-1,1,1,3,5,5,5-heptamethyl trisiloxane (CDTS), polyoxyethylene (5 mol) glyceryl monostearate (GMS-5), higher alcohol. This is the first report to indicate that a silicone surfactant can form an α-form hydrated crystal. The physicochemical properties of this system were characterized by small and wide angle X-ray scattering (SWAXS), differential scanning calorimetry (DSC), and diffusion-ordered NMR spectroscopy (DOSY) experiments. SWAXS and DSC measurements revealed that a plurality of crystalline phases coexist in the CDTS/higher alcohol/water ternary system. By adding GMS-5 to the ternary system, however, a wide region of a single α-form hydrated crystalline phase was obtained. The self-diffusion coefficients (D sel ) from the NMR measurements suggested that all of the CDTS, GMS-5, and higher alcohol molecules were incorporated into the same α-form hydrated crystals.

Complex Mixture Analysis of Organic Compounds in Yogurt by NMR Spectroscopy

PubMed Central

Lu, Yi; Hu, Fangyu; Miyakawa, Takuya; Tanokura, Masaru

2016-01-01

NMR measurements do not require separation and chemical modification of samples and therefore rapidly and directly provide non-targeted information on chemical components in complex mixtures. In this study, one-dimensional (1H, 13C, and 31P) and two-dimensional (1H-13C and 1H-31P) NMR spectroscopy were conducted to analyze yogurt without any pretreatment. 1H, 13C, and 31P NMR signals were assigned to 10 types of compounds. The signals of α/β-lactose and α/β-galactose were separately observed in the 1H NMR spectra. In addition, the signals from the acyl chains of milk fats were also successfully identified but overlapped with many other signals. Quantitative difference spectra were obtained by subtracting the diffusion ordered spectroscopy (DOSY) spectra from the quantitative 1H NMR spectra. This method allowed us to eliminate interference on the overlaps; therefore, the correct intensities of signals overlapped with those from the acyl chains of milk fat could be determined directly without separation. Moreover, the 1H-31P HMBC spectra revealed for the first time that N-acetyl-d-glucosamine-1-phosphate is contained in yogurt. PMID:27322339

[Methylmercury exposure in the general population; toxicokinetics; differences by gender, nutritional and genetic factors].

PubMed

González-Estecha, Montserrat; Bodas-Pinedo, Andrés; Guillén-Pérez, José Jesús; Rubio-Herrera, Miguel Ángel; Ordóñez-Iriarte, José M; Trasobares-Iglesias, Elena M; Martell-Claros, Nieves; Martínez-Álvarez, Jesús Román; Farré-Rovira, Rosaura; Herráiz-Martínez, Miguel Ángel; Martínez-Astorquiza, Txantón; Calvo-Manuel, Elpidio; Sáinz-Martín, María; Bretón-Lesmes, Irene; Prieto-Menchero, Santiago; Llorente-Ballesteros, M Teresa; Martínez-García, M José; Salas-Salvadó, Jordi; Bermejo-Barrera, Pilar; García-Donaire, José Antonio; Cuadrado-Cenzual, M Ángeles; Gallardo-Pino, Carmen; Moreno-Rojas, Rafael; Arroyo-Fernández, Manuel; Calle-Pascual, Alfonso

2014-11-01

Mercury is an environmental toxicant that causes numerous adverse effects on human health and natural ecosystems. The factors that determine the existance of adverse effects, as well as their severity are, among others: the chemical form of mercury (elemental, inorganic, organic), dosis, age, period of exposure, pathways of exposure and environmental, nutritional and genetic factors. In the aquatic cycle of mercury, once it has been deposited, it is transformed into methylmercury due to the action of certain sulphate-reducing bacteria, which bioaccumulates in the aquatic organisms and moves into the food chain. The methylmercury content of large, long-lived fish such as swordfish, shark, tuna or marlin, is higher. Methylmercury binds to protein in fish and is therefore not eliminated by cleaning or cooking the fish. Fetuses and small children are more vulnerable to the neurotoxic effects of methylmercury from the consumption of contaminated fish. Methylmercury is absorbed in the gastrointestinal tract and crosses the blood-brain barrier and the placenta. The intake of certain dietary components such as polyunsaturated fatty acids, selenium, fiber, thiol compounds, certain phytochemicals and other nutrients can modify methylmercury bioaccesibility and its toxicity. Apart from environmental factors, genetic factors can influence mercury toxicity and explain part of the individual vulnerability. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Stability of hydrophilic vitamins mixtures in the presence of electrolytes and trace elements for parenteral nutrition: a nuclear magnetic resonance spectroscopy investigation.

PubMed

Uccello-Barretta, Gloria; Balzano, Federica; Aiello, Federica; Falugiani, Niccolò; Desideri, Ielizza

2015-03-25

In total parenteral nutrition (TPN), especially in the case of preterm infants, simultaneous administration of vitamins and trace elements is still a problematic issue: guidelines put in evidence the lack of specific documentation. In this work NMR spectroscopy was applied to the study of vitamins (pyridoxine hydrochloride, thiamine nitrate, riboflavin-5'-phosphate and nicotinamide) stability in presence of salts and trace elements. Vitamins in D2O were first analyzed by (1)H NMR spectroscopy in absence of salts and trace elements; changes in chemical shifts or in diffusion coefficients, measured by NMR DOSY technique, were analyzed. The effects of salts and trace elements on single vitamins and on their admixtures were then investigated by performing quantitative analyses during 48h. Selected vitamins are subject to intermolecular interactions. No degradative effects were observed in presence of salts and trace elements. Only riboflavin-5'-phosphate is subject to precipitation in presence of divalent cations; however, at low concentration and in presence of other vitamins this effect was not observed. Solutions analyzed, in the condition of this study, are stable for at least 48h and vitamins and trace elements can be administered together in TPN. Copyright © 2014 Elsevier B.V. All rights reserved.

[Ag115S34(SCH2C6H4 t Bu)47(dpph)6]: synthesis, crystal structure and NMR investigations of a soluble silver chalcogenide nanocluster.

PubMed

Bestgen, Sebastian; Fuhr, Olaf; Breitung, Ben; Kiran Chakravadhanula, Venkata Sei; Guthausen, Gisela; Hennrich, Frank; Yu, Wen; Kappes, Manfred M; Roesky, Peter W; Fenske, Dieter

2017-03-01

With the aim to synthesize soluble cluster molecules, the silver salt of (4-( tert -butyl)phenyl)methanethiol [AgSCH 2 C 6 H 4 t Bu] was applied as a suitable precursor for the formation of a nanoscale silver sulfide cluster. In the presence of 1,6-(diphenylphosphino)hexane (dpph), the 115 nuclear silver cluster [Ag 115 S 34 (SCH 2 C 6 H 4 t Bu) 47 (dpph) 6 ] was obtained. The molecular structure of this compound was elucidated by single crystal X-ray analysis and fully characterized by spectroscopic techniques. In contrast to most of the previously published cluster compounds with more than a hundred heavy atoms, this nanoscale inorganic molecule is soluble in organic solvents, which allowed a comprehensive investigation in solution by UV-Vis spectroscopy and one- and two-dimensional NMR spectroscopy including 31 P/ 109 Ag-HSQC and DOSY experiments. These are the first heteronuclear NMR investigations on coinage metal chalcogenides. They give some first insight into the behavior of nanoscale silver sulfide clusters in solution. Additionally, molecular weight determinations were performed by 2D analytical ultracentrifugation and HR-TEM investigations confirm the presence of size-homogeneous nanoparticles present in solution.

Interaction of water, alkyl hydroperoxide, and allylic alcohol with a single-site homogeneous Ti-Si epoxidation catalyst: A spectroscopic and computational study.

PubMed

Urakawa, Atsushi; Bürgi, Thomas; Skrabal, Peter; Bangerter, Felix; Baiker, Alfons

2005-02-17

Tetrakis(trimethylsiloxy)titanium (TTMST, Ti(OSiMe3)4) possesses an isolated Ti center and is a highly active homogeneous catalyst in epoxidation of various olefins. The structure of TTMST resembles that of the active sites in some heterogeneous Ti-Si epoxidation catalysts, especially silylated titania-silica mixed oxides. Water cleaves the Ti-O-Si bond and deactivates the catalyst. An alkyl hydroperoxide, TBHP (tert-butyl hydroperoxide), does not cleave the Ti-O-Si bond, but interacts via weak hydrogen-bonding as supported by NMR, DOSY, IR, and computational studies. ATR-IR spectroscopy combined with computational investigations shows that more than one, that is, up to four, TBHP can undergo hydrogen-bonding with TTMST, leading to the activation of the O-O bond of TBHP. The greater the number of TBHP molecules that form hydrogen bonds to TTMST, the more electrophilic the O-O bond becomes, and the more active the complex is for epoxidation. An allylic alcohol, 2-cyclohexen-1-ol, does not interact strongly with TTMST, but the interaction is prominent when it interacts with the TTMST-TBHP complex. On the basis of the experimental and theoretical findings, a hydrogen-bond-assisted epoxidation mechanism of TTMST is suggested.

Trends in corrected lung cancer mortality rates in Brazil and regions.

PubMed

Malta, Deborah Carvalho; Abreu, Daisy Maria Xavier de; Moura, Lenildo de; Lana, Gustavo C; Azevedo, Gulnar; França, Elisabeth

2016-06-27

To describe the trend in cancer mortality rates in Brazil and regions before and after correction for underreporting of deaths and redistribution of ill-defined and nonspecific causes. The study used data of deaths from lung cancer among the population aged from 30 to 69 years, notified to the Mortality Information System between 1996 and 2011, corrected for underreporting of deaths, non-registered sex and age , and causes with ill-defined or garbage codes according to sex, age, and region. Standardized rates were calculated by age for raw and corrected data. An analysis of time trend in lung cancer mortality was carried out using the regression model with autoregressive errors. Lung cancer in Brazil presented higher rates among men compared to women, and the South region showed the highest death risk in 1996 and 2011. Mortality showed a trend of reduction for males and increase for women. Lung cancer in Brazil presented different distribution patterns according to sex, with higher rates among men and a reduction in the mortality trend for men and increase for women. Descrever a tendência da mortalidade por câncer de pulmão no Brasil e regiões, antes e após as correções por sub-registro de óbitos, redistribuição de causas mal definidas e causas inespecíficas. Foram utilizados dados de óbitos por câncer de pulmão da população de 30 a 69 anos, notificados ao Sistema de Informação sobre Mortalidade, entre 1996 e 2011, corrigidos para sub-registro de óbitos, declaração de sexo e idade ignorados e causas com códigos mal definidos e inespecíficos segundo sexo, idade e região. Foram calculadas taxas padronizadas por idade para dados brutos e corrigidos. Realizou-se análise da tendência temporal da mortalidade por câncer de pulmão por meio do modelo de regressão com erros autorregressivos. O câncer de pulmão no Brasil apresentou taxas mais elevadas em homens que em mulheres e a região Sul foi a que apresentou maior risco de morte em 1996 e 2011. A mortalidade tendeu a reduzir para o sexo masculino e a aumentar para o sexo feminino. O câncer de pulmão no Brasil apresenta padrão de distribuição diferente segundo sexo, com taxas mais elevadas em homens e com redução da tendência de mortalidade para o sexo masculino e aumento das taxas para o sexo feminino.

Relaciones entre el sueño y la adicción

PubMed Central

Cañellas, Francesca; de Lecea, Luis

2016-01-01

Resumen La interacción entre los trastornos del sueño y el abuso de sustancias es ya conocida, pero seguramente más compleja de lo que se pensaba. Existe tanto una relación positiva entre tener un trastorno por uso de substancias y sufrir un trastorno de sueño, como viceversa. Los efectos sobre el sueño dependen de la substancia utilizada, pero se ha demostrado que tanto durante su uso como en período de abstinencia los consumidores tienen diferentes problemas de sueño y fundamentalmente un sueño más fragmentado. Sabemos que hay que tener en cuenta los problemas de sueño para evitar recaídas en la adicción. Investigaciones recientes indican que el sistema hipocretinérgico definido por el neuropéptido hipocretina/orexina (Hcrt/ox), localizado en el hipotálamo lateral e implicado entre otros en la regulación del ciclo sueño-vigilia, jugaría un papel importante en las conductas adictivas. Diferentes estudios han demostrado interacciones entre el sistema hipocretinérgico, los circuitos de respuesta aguda al estrés y los sistemas de recompensa. También sabemos que la activación optogenética selectiva del sistema hipocretinérgico incrementa la probabilidad de la transición del sueño a la vigilia, y también es suficiente para iniciar un comportamiento compulsivo de recaída adictiva. La activación del sistema hipocretinérgico podría explicar la hipervigilia asociada al estrés y a la adicción. El mayor conocimiento de esta interacción permitiría entender mejor los mecanismos de la adicción y encontrar nuevas estrategias para el tratamiento de las adicciones. PMID:23241715

The threat of disease increases as species move toward extinction.

PubMed

Heard, Matthew J; Smith, Katherine F; Ripp, Kelsey; Berger, Melanie; Chen, Jane; Dittmeier, Justin; Goter, Maggie; McGarvey, Stephen T; Ryan, Elizabeth

2013-12-01

At local scales, infectious disease is a common driver of population declines, but globally it is an infrequent contributor to species extinction and endangerment. For species at risk of extinction from disease important questions remain unanswered, including when does disease become a threat to species and does it co-occur, predictably, with other threats? Using newly compiled data from the International Union for Conservation of Nature (IUCN) Red List, we examined the relative role and co-occurrence of threats associated with amphibians, birds, and mammals at 6 levels of extinction risk (i.e., Red List status categories: least concern, near threatened, vulnerable, endangered, critically endangered, and extinct in the wild/extinct). We tested the null hypothesis that the proportion of species threatened by disease is the same in all 6 Red List status categories. Our approach revealed a new method for determining when disease most frequently threatens species at risk of extinction. The proportion of species threatened by disease varied significantly between IUCN status categories and linearly increased for amphibians, birds, and all species combined as these taxa move from move from least concern to critically endangered. Disease was infrequently the single contributing threat. However, when a species was negatively affected by a major threat other than disease (e.g., invasive species, land-use change) that species was more likely to be simultaneously threatened by disease than species that had no other threats. Potential drivers of these trends include ecological factors, clustering of phylogenetically related species in Red List status categories, discovery bias among species at greater risk of extinction, and availability of data. We echo earlier calls for baseline data on the presence of parasites and pathogens in species when they show the first signs of extinction risk and arguably before. La Amenaza de Enfermedades Incrementa a Medida que las Especies se Aproximan a la Extinción. © 2013 Society for Conservation Biology.

CONTAMINACIÓN AMBIENTAL, VARIABILIDAD CLIMÁTICA Y CAMBIO CLIMÁTICO: UNA REVISIÓN DEL IMPACTO EN LA SALUD DE LA POBLACIÓN PERUANA

PubMed Central

Gonzales, Gustavo F.; Zevallos, Alisson; Gonzales-Castañeda, Cynthia; Nuñez, Denisse; Gastañaga, Carmen; Cabezas, César; Naeher, Luke; Levy, Karen; Steenland, Kyle

2015-01-01

RESUMEN El presente artículo es una revisión sobre la contaminación del agua, el aire y el efecto del cambio climático en la salud de la población peruana. Uno de los principales contaminantes del aire es el material particulado menor de 2,5 μ (PM 2,5), en la ciudad de Lima, anualmente 2300 muertes prematuras son atribuibles a este contaminante. Otro problema es la contaminación del aire domiciliario por el uso de cocinas con combustible de biomasa, donde la exposición excesiva a PM 2,5 dentro de las casas es responsable de aproximadamente 3000 muertes prematuras anuales entre adultos, con otro número desconocido de muertes entre niños debido a infecciones respiratorias. La contaminación del agua tiene como principales causas los desagües vertidos directamente a los ríos, minerales (arsénico) de varias fuentes, y fallas de las plantas de tratamiento. En el Perú, el cambio climático puede impactar en la frecuencia y severidad del fenómeno de El Niño oscilación del sur (ENSO) que se ha asociado con un incremento en los casos de enfermedades como cólera, malaria y dengue. El cambio climático incrementa la temperatura y puede extender las áreas afectadas por enfermedades transmitidas por vectores, además de tener efecto en la disponibilidad del agua y en la contaminación del aire. En conclusión, el Perú, pasa por una transición de factores de riesgo ambientales, donde coexisten riesgos tradicionales y modernos, y persisten los problemas infecciosos y crónicos, algunos de los cuales se asocian con problemas de contaminación de agua y de aire. PMID:25418656

[Not Available].

PubMed

Torres Díaz, Cristina V; Martín Peña, Gonzalo; Ezquiaga, Elena; Navas García, Marta; García de Sola, Rafael

2016-07-19

Gracias a los avances técnicos en técnicas neuroquirúrgicas, y debido a que el diagnóstico y la clasificación de las enfermedades psiquiátricas han evolucionado significativamente a lo largo de las últimas décadas, se están desarrollando tratamientos a nivel experimental para aquellos pacientes resistentes al manejo conservador.La anorexia nerviosa es una enfermedad de prevalencia creciente, con la tasa de mortalidad más elevada dentro de los trastornos psiquiátricos, y con aproximadamente un 20% de pacientes que presentan una evolución tórpida. Para estos pacientes que no responden a manejo conservador, la estimulación cerebral profunda ha surgido como una alternativa terapéutica, si bien la literatura especializada al respecto es escasa.A continuación presentamos una revisión de la fisiopatología de la anorexia nerviosa, así como de los distintos tratamientos neuroquirúrgicos realizados a lo largo de la historia. Se detalla la perspectiva de tratamiento quirúrgico actual, así como los aspectos éticos que se han de considerar en relación con el surgimiento de estas nuevas terapias.

CONVENTIONAL VIDEOENDOSCOPY CAN IDENTIFY HELICOBACTER PYLORI GASTRITIS?

PubMed

Gomes, Alexandre; Skare, Thelma Larocca; Prestes, Manoel Alberto; Costa, Maiza da Silva; Petisco, Roberta Dombroski; Ramos, Gabriela Piovezani

2016-01-01

Studies with latest technologies such as endoscopy with magnification and chromoendoscopy showed that various endoscopic aspects are clearly related to infection by Helicobacter pylori (HP). The description of different patterns of erythema in gastric body under magnification of images revived interest in identifying these patterns by standard endoscopy. To validate the morphologic features of gastric mucosa related to H. pylori infection gastritis allowing predictability of their diagnosis as well as proper targeting biopsies. Prospective study of 339 consecutive patients with the standard videoendoscope image analysis were obtained, recorded and stored in a program database. These images were studied with respect to the presence or absence of H. pylori, diagnosed by rapid urease test and/or by histological analysis. Were studied: a) normal mucosa appearance; b) mucosal nodularity; c) diffuse nonspecific erythema or redness (with or without edema of folds and exudate) of antrum and body; d) mosaic pattern with focal area of hyperemia; e) erythema in streaks or bands (red streak); f) elevated (raised) erosion; g) flat erosions; h) fundic gland polyps. The main exclusion criteria were the use of drugs, HP pre-treatment and other entities that could affect results. Applying the exclusion criteria, were included 170 of the 339 patients, of which 52 (30.58%) were positive for HP and 118 negative. On the positive findings, the most associated with infection were: nodularity in the antrum (26.92%); presence of raised erosion (15.38%) and mosaic mucosa in the body (21.15%). On the negative group the normal appearance of the mucosa was 66.94%; erythema in streaks or bands in 9.32%; flat erosions 11.86%; and fundic gland polyps 11.86%. Endoscopic findings are useful in the predictability of the result and in directing biopsies. The most representative form of HP related gastritis was the nodularity of the antral mucosa. The raised erosion and mucosa in mosaic in the body are suggestive but not specific to the infection. The other forms were not conclusive of the presence of HP. Estudos com tecnologias mais recentes como endoscopia com magnificação e cromoscopia mostraram que vários aspectos endoscópicos estão claramente associados à infecção por Helicobacter pylori. A descrição de padrões diferenciados de enantema no corpo gástrico através da magnificação de imagens reavivou o interesse na identificação desses padrões pela endoscopia convencional. Validar os padrões morfológicos de mucosa gástrica usando videogastroendoscopia convencional relacionados à gastrite por infecção por Helicobacter pylori, permitindo previsibilidade do seu diagnóstico e o direcionamento de biópsias. Estudo prospectivo de 339 pacientes consecutivos com análise das imagens de videogastroendoscopia obtidas, gravadas e armazenadas em banco de dados. Estas imagens foram estudadas com relação à presença ou não do Helicobacter pylori diagnosticado por teste rápido de urease e/ou por pesquisa direta por estudo anatomopatológico. Foram estudados: a) aspecto normal da mucosa; b) nodularidade da mucosa; c) enantema inespecífico difuso de antro e corpo; d) enantema em mosaico ou salpicado; e) enantema em estrias ou faixas; f) erosões elevadas; g) erosões planas; h) pólipos de glândulas fúndicas. Os principais critérios de exclusão foram o uso de medicamentos, tratamento prévio de HP e outras entidades que pudessem interferir nos resultados. Aplicando os critérios de exclusão, incluíram-se 170 dos 339 pacientes sendo 52 (30,58%) positivos para Helicobacter pylori e 118 negativos. No grupo positivo os achados que mais se associaram com a infecção foram: nodularidade no antro (26,92%); presença de erosões elevadas (15,38%) e mucosa em mosaico no corpo (21,15%). No grupo negativo o aspecto normal da mucosa foi de 66,94%; enantema em estrias ou faixas em 9,32%; erosões planas em 11,86%; e pólipos de glândulas fúndicas 11,86%. Achados endoscópicos são úteis na previsibilidade de localização e direcionamento de biópsias na pesquisa do HP. A mais representativa forma de gastrite por HP foi o achado de nodularidade na mucosa antral. As erosões elevadas e mucosa em mosaico no corpo são sugestivas, mas não específicas da infecção. As demais formas não foram conclusivas da presença do HP.

Study of the interactions between a proline-rich protein and a flavan-3-ol by NMR: residual structures in the natively unfolded protein provides anchorage points for the ligands.

PubMed

Pascal, Christine; Paté, Franck; Cheynier, Véronique; Delsuc, Marc-André

2009-09-01

Astringency is one of the major organoleptic properties of food and beverages that are made from plants, such as tea, chocolate, beer, or red wine. This sensation is thought to be due to interactions between tannins and salivary proline-rich proteins, which are natively unfolded proteins. A human salivary proline-rich protein, namely IB-5, was produced by the recombinant method. Its interactions with a model tannin, epigallocatechin gallate (EGCG), the major flavan-3-ol in green tea, were studied here. Circular dichroism experiments showed that IB-5 presents residual structures (PPII helices) when the ionic strength is close to that in saliva. In the presence of these residual structures, IB-5 undergoes an increase in structural content upon binding to EGCG. NMR data corroborated the presence of preformed structural elements within the protein prior to binding and a partial assignment was proposed, showing partial structuration. TOCSY experiments showed that amino acids that are involved in PPII helices are more likely to interact with EGCG than those in random coil regions, as if they were anchorage points for the ligand. The signal from IB-5 in the DOSY NMR spectrum revealed an increase in polydispersity upon addition of EGCG while the mean hydrodynamic radius remained unchanged. This strongly suggests the formation of IB-5/EGCG aggregates.

Frost Grape Polysaccharide (FGP), an Emulsion-Forming Arabinogalactan Gum from the Stems of Native North American Grape Species Vitis riparia Michx.

PubMed

Price, Neil P J; Vermillion, Karl E; Eller, Fred J; Vaughn, Steven F

2015-08-19

A new arabinogalactan is described that is produced in large quantity from the cut stems of the North American grape species Vitis riparia (Frost grape). The sugar composition consists of l-arabinofuranose (l-Araf, 55.2%) and d-galactopyranose (d-Galp 30.1%), with smaller components of d-xylose (11.2%), d-mannose (3.5%), and glucuronic acid (GlcA, ∼2%), the latter linked via a galactosyl residue. Permethylation identified 3-linked Galp residues, some substituted at the 2-position with Galp or Manp, terminal Araf and Xylp, and an internal 3-substituted Araf. NMR (HSQC, TOCSY, HMBC, DOSY) identified βGalp and three αAraf spin systems, in an Araf-α1,3-Araf-α1,2-Araf-α1,2-Galp structural motif. Diffusion-ordered NMR showed that the FGP has a molecular weight of 1-10 MDa. Unlike gum arabic, the FGP does not contain a hydroxyproline-rich protein (HPRP). FGP forms stable gels at >15% w/v and at 1-12% solutions are viscous and are excellent emulsifiers of flavoring oils (grapefruit, clove, and lemongrass), giving stable emulsions for ≥72 h. Lower concentrations (0.1% w/v) were less viscous, yet still gave stable grapefruit oil/water emulsions. Hence, FGP is a β1,3-linked arabinogalactan with potential as a gum arabic replacement in the food and beverage industries.

End-Group Effects on the Properties of PEG-co-PGA Hydrogels

PubMed Central

Bencherif, Sidi A.; Srinivasan, Abiraman; Sheehan, Jeffrey A.; Walker, Lynn M.; Gayathri, Chakicherla; Gil, Roberto; Hollinger, Jeffrey O.; Matyjaszewski, Krzysztof; Washburn, Newell R.

2009-01-01

A series of resorbable poly(ethylene glycol)-co-poly(glycolic acid) macromonomers have been synthesized with the chemistries from three different photopolymerizable end-groups (acrylates, methacrylates, and urethane methacrylates). The aim of the study is to examine the effects of the chemistry of the cross-linker group on the properties of photocross-linkable hydrogels. PEG-co-PGA (4KG5) hydrogels were prepared by photopolymerization with high vinyl group conversion as confirmed by 1H NMR spectroscopy using DOSY 1D pulse sequence. Our study reveals that the nature of end-groups in a moderately amphiphilic polymer can adjust the distribution and size of the micellar configuration in water leading to changes in the macroscopic structure of hydrogels. By varying the chemistry of the cross-linker group (diacrylates; DA, dimethacrylates; DM, and urethane dimethacrylates; UDM), we determined that the hydrophobocity of a single core polymer consisting of poly(glycolic acid) could be fine-tuned leading to significant variations in the mechanical, swelling, and degradation properties of the gels. In addition, the effects of cross-linker chemistry on cytotoxicity and proliferation were examined. Cytotoxicity assays showed that all the three types of hydrogels (4KG5 DA, DM, and UDM) were biocompatible and the introduction of RGD ligand enhanced cell adhesion. However, differences in gel properties and stability differentially affected the spreading and proliferation of myoblast C2C12 cells. PMID:19328754

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

Kropp, J.; Heck, I.; Reske, S.N.

In aortic insufficiency (AI) the inhibition of the stimulated Renin-Angiotensin-System (RAS) by Captopril (C) reduced afterload and leads consequently to a diminished regurgitation fraction (RF). In 17 patients (pts) with pure severe AI RF, left ventricular ejection fraction (LVEFE) and heart rate were determined before (1) and 1 hr after (2) administration of 25 mg of C.Long term dosis was 3 x 25 mg of C and follow up time was 3-11 months (medium:6). The values were determined by gated radionuclide ventriculography using red blood cells labeled in vivo with 15 mCi Tc-99mROI's were selected over both ventricles in enddiastolicmore » and endsystolic frames. Ventricular boundaries were defined by a fourier phase image overlay. RF was calculated by the background corrected count rate ratio of left and right ventricular ROI. Systolic and diastolic blood pressure (BPs,BPd), plasma levels of angiotensin I,II(A1,A2) and the activity of angiotensin converting enzyme (ACE) were determined before and 1 hr after C administration. After C there is a decrease in RF which persists in the long term follow period in up to to now 8 pts. The authors conclude: inhibition of ACE reduces significantly aortic regurgitation in patients with AI and has thus a beneficial effect on left ventricular performance. This effect persists in long term treatment and therefore seems beneficial to delay the point of operation.« less

Gabapentina a dosis de 300 vs. 450 mg como premedicación anestésica para hipertensión reactiva, ansiedad y analgesia.

PubMed

Rascón-Martínez, Dulce María; Guzmán-Sánchez, Joaquín Antonio; Corral-Urdapilleta, Nora Paulina; Arguelles-Uribe, Gema Damaris; Velázquez-Loeza, Jazmín; Soto-Palma, Gustavo; Carrillo-Torres, Orlando

Observar el comportamiento de la gabapentina para aminorar la hipertensión reactiva secundaria a ansiedad y dolor en pacientes sometidos a cirugía oftálmica, así como el consumo de opiáceos entre los grupos. Ensayo clínico controlado aleatorizado y doble ciego que analizó a 125 pacientes divididos en tres grupos: grupo A, gabapentina 300 mg; grupo B, gabapentina 450 mg; grupo C, amaranto en grageas como control 2 horas antes del procedimiento quirúrgico. Se utilizó la prueba de ji al cuadrado para variables sociodemográficas y ANOVA de un factor para variables numéricas continuas. Se consideró como significativo un valor de p < 0.05 para un estudio de dos colas con un poder beta del 80%. La ansiedad y la analgesia transoperatoria y posoperatoria tuvieron diferencias significativas entre los grupos. Se encontró menor consumo de opiáceos en los grupos que usaron gabapentina. La gabapentina por vía oral, 300 o 450 mg, 2 horas antes de la cirugía, reduce el dolor, la ansiedad y el consumo de opiáceos durante el posoperatorio en pacientes sometidos a cirugía oftalmológica. Copyright: © 2018 SecretarÍa de Salud

Biorelevant physicochemical profiling of (E)- and (Z)-resveratrol determined from isomeric mixtures.

PubMed

Orgován, Gábor; Gonda, Imre; Noszál, Béla

2017-05-10

Biorelevant, isomer-specific physicochemical parameters of resveratrol, a multifunctional component in red wines, with cardioprotective, anti-Alzheimer and several other pharmacologic activities were determined. The parameters include site-specific basicities, lipophilicities, solubilities and diffusion constants for the two geometric isomers. The protonation equilibria of (E)- and (Z)-resveratrol were monitored by 1 H NMR-pH titrations. Five closely related auxiliary compounds ((E)-pinostilbene, (Z)-pinostilbene, (E)-pterostilbene, (Z)-pterostilbene and resorcinol) were also studied. Combining the datasets, the group-specific protonation constants of resveratrol isomers were determined. The results show that (Z)-resveratrol is more basic at every protonation site than the (E)-isomer. Lipophilicities are quantified in terms of logP values and were determined by octanol/water partition experiments and quantitative NMR spectroscopy: (E)-resveratrol was found to be more lipophilic. Since the molecular geometries of the isomers differ, diffusion ordered NMR spectroscopy (DOSY) experiments were also carried out to quantify the diffusion capabilities of the isomers: (Z)-resveratrol of bent shape has a slightly higher diffusion coefficient than its extended (E) counterpart. A striking 10-fold difference of water solubility was found in favor of the (Z) isomer, due obviously to the reduced water-repellent character in the more compact molecule. This is so far the greatest recorded solubility difference between geometric isomers of any compounds. Copyright © 2016. Published by Elsevier B.V.

Using supramolecular binding motifs to provide precise control over the ratio and distribution of species in multiple component films grafted on surfaces: demonstration using electrochemical assembly from aryl diazonium salts.

PubMed

Gui, Alicia L; Yau, Hon Man; Thomas, Donald S; Chockalingam, Muthukumar; Harper, Jason B; Gooding, J Justin

2013-04-16

Supramolecular interactions between two surface modification species are explored to control the ratio and distribution of these species on the resultant surface. A binary mixture of aryl diazonium salts bearing oppositely charged para-substituents (either -SO3(-) or -N(+)(Me)3), which also reduce at different potentials, has been examined on glassy carbon surfaces using cyclic voltammetry and X-ray photoelectron spectroscopy (XPS). Striking features were observed: (1) the two aryl diazonium salts in the mixed solution undergo reductive adsorption at the same potential which is distinctively less negative than the potential required for the reduction of either of the two aryl diazonium salts alone; (2) the surface ratio of the two phenyl derivatives is consistently 1:1 regardless of the ratio of the two aryl diazonium salts in the modification solutions. Homogeneous distribution of the two oppositely charged phenyl species on the modified surface has also been suggested by XPS survey spectra. Diffusion coefficient measurements by DOSY NMR and DFT based computation have indicated the association of the two aryl diazonium species in the solution, which has led to changes in the molecular orbital energies of the two species. This study highlights the potential of using intermolecular interactions to control the assembly of multicomponent thin layers.

Research on large area VUV-sensitive gaseous photomultipliers for cryogenic applications

NASA Astrophysics Data System (ADS)

Coimbra, Artur Emanuel Cardoso

Desde cedo que a comunidade cientifica compreendeu que gases nobres em liquido sao excelentes meios de deteccao de radiacao, combinando a sua elevada densidade, elevado grau de homogeneidade e de elevado rendimento de cintilacao. Para alem destas caracteristicas inerentes, estes tem a potencialidade de fornecer ambos sinais de ionizacao - criando electroes livres - e cintilacao em resposta a interaccao com radiacao ionizante e, tendo em vista a sua aplicacao em experiencias de eventos raros relacionados com fisica de neutrinos ou materia-escura, a capacidade de autoblindagem garante a exclusao de eventos induzidos por radiacao de fundo. O facto de nao absorverem a sua propria luz, emergente dos eventos de cintilacao, permite a expansao deste tipo de detectores ate grandes volumes, sendo que as colaboracoes mais recentes propoem detectores com dezenas de toneladas de xenon em estado liquido. As experiencias actuais que usam gases nobres em estado liquido empregam xenon ou argon numa so fase (estado liquido) ou em dupla-fase (estado liquido + gasoso) e as suas aplicacoes abrangem desde as ja referidas experiencias de procura de eventos raros, passando por imagiologia medica tais como detectores de radiacao gama para PET ou câmaras Compton "3-gamma" em combinacao com PET, passando tambem por aplicacoes de seguranca como sistemas de inspeccao para deteccao de material fissil e, finalmente, em câmaras Compton para aplicacoes de astrofisica. Em ambas as configuracoes a leitura dos sinais de cintilacao e geralmente feita atraves de um grande numero de dispendiosos fotomultiplicadores de vacuo agrupados. A presente tese de doutoramento e dedicada aos fotomultiplicadores gasosos de grande area para aplicacoes criogenicas desenvolvidos no contexto do programa doutoral, tendo em vista a sua eventual aplicacao como um dispositivo complementar aos metodos existentes de deteccao de cintilacao, para aplicacao em futuras experiencias de grande escala. Esta pesquisa foi direccionada tendo em vista o desenvolvimento de eficientes fotomultiplicadores gasosos de grande area, potencialmente mais economicos por unidade de area, baseados em "Thick Gas-Electron Multipliers" (THGEMs). Combinando fotocatodos de alta eficiencia com multiplicadores gasosos de electroes capazes de atingir elevado ganho em carga obteve-se assim um dispositivo com elevada sensibilidade para a deteccao de fotoes unicos, com a possibilidade de discriminacao em posicao com resolucao espacial inferior a um milimetro e com resolucao temporal da ordem de poucos nano segundos. Contrariamente ao que sucede com a tecnologia de vacuo actualmente, com este dispositivo a localizacao em posicao de fotoes em grandes areas e feita num unico dispositivo integrando electronica habitualmente utilizada em experiencias de rastreamento de particulas. Neste trabalho o fotomultiplicador gasoso desenvolvido consiste numa cadeia de THGEMs combinados com um fotocatodo de iodeto de cesio (CsI) sensivel ao ultravioleta enquanto que os testes criogenicos foram realizados na Time Projection Chamber (TPC) de dupla fase de xenon liquido recentemente desenvolvida no Weizmann Institute of Science (WILiX). (Abstract shortened by ProQuest.).

Analysis of the discrepancies identified during medication reconciliation on patient admission in cardiology units: a descriptive study.

PubMed

Lombardi, Natália Fracaro; Mendes, Antonio Eduardo Matoso; Lucchetta, Rosa Camila; Reis, Wálleri Christini Torelli; Fávero, Maria Luiza Drechsel; Correr, Cassyano Januário

2016-08-15

this observational study aimed to describe the discrepancies identified during medication reconciliation on patient admission to cardiology units in a large hospital. the medication history of patients was collected within 48 hours after admission, and intentional and unintentional discrepancies were classified as omission, duplication, dose, frequency, timing, and route of drug administration. most of the patients evaluated were women (58.0%) with a mean age of 59 years, and 75.5% of the patients had a Charlson comorbidity index score between 1 and 3. Of the 117 discrepancies found, 50.4% were unintentional. Of these, 61.0% involved omission, 18.6% involved dosage, 18.6% involved timing, and 1.7% involved the route of drug administration. this study revealed a high prevalence of discrepancies, most of which were related to omissions, and 50% were unintentional. These results reveal the number of drugs that are not reincorporated into the treatment of patients, which can have important clinical consequences. este estudo observacional teve como objetivo descrever discrepâncias encontradas na realização de conciliação medicamentosa de pacientes admitidos em unidades de cardiologia de um hospital de grande porte. a história de medicação dos pacientes foi coletada dentro de 48h após a admissão, e as discrepâncias, identificadas como intencionais ou não intencionais, foram classificadas como de: omissão, duplicidade, dose, frequência, intervalo e via. a maioria dos pacientes incluídos pertençia ao sexo feminino (58,0%), com idade média de 59 anos, e com índice de comorbidades de Charlson entre 1 e 3 (75,5% dos casos). Das 117 discrepâncias encontradas, 50,4% foram não intencionais. Dessas, 61,0% foram de omissão, 18,6% de dose, 18,6% de intervalo e 1,7% de via de administração. o estudo mostra a alta prevalência de discrepâncias, principalmente de omissão, sendo quase metade não intencionais. Esse dado remete ao número de medicamentos que não são reincorporados ao tratamento dos pacientes, podendo repercutir em consequências clínicas importantes. este estudio observacional tuvo como objetivo describir discrepancias encontradas en la realización de la conciliación medicamentosa de pacientes admitidos en unidades de cardiología de un hospital de gran porte. la historia de medicación de los pacientes fue recolectada dentro de 48h después de la admisión, y las discrepancias, identificadas como intencionales o no intencionales, fueron clasificadas como: omisión, duplicidad, dosis, frecuencia, intervalo y vía. la mayoría de los pacientes incluidos pertenecía al sexo femenino (58,0%), con edad promedio de 59 años, y con índice de comorbilidad de Charlson entre 1 y 3 (75,5% de los casos). De las 117 discrepancias encontradas, 50,4% fueron no intencionales. De estas, 61,0% fueron de omisión, 18,6% de dosis, 18,6% de intervalo y 1,7% de vía de administración. el estudio muestra la alta prevalencia de discrepancias, principalmente de omisión, siendo casi mitad de ellas no intencionales. Ese dato nos indica el número de medicamentos que no son reincorporados al tratamiento de los pacientes, lo que puede repercutir en consecuencias clínicas importantes.

Experiencias atípicas psicóticas y cuasi-psicóticas en adolescentes puertorriqueños/as deprimidos/as: Prevalencia y factores asociados1

PubMed Central

López Robledo, Yaritza M.; Cumba-Avilés, Eduardo; Bernal, Guillermo

2018-01-01

Se examinó la prevalencia de experiencias atípicas psicóticas y cuasi-psicóticas y se identificaron factores asociados a éstas en 162 jóvenes puertorriqueños/as entre 13 y 17.5 años. Se evaluó la sintomatología depresiva, la ideación suicida, así como la presencia o historia de experiencias atípicas, eventos traumáticos y maltrato o abuso. Las experiencias atípicas estuvieron asociadas (p<.05) a ser fémina, a tener enfermedades físicas, a experimentar eventos traumáticos, a haber recibido tratamiento para la depresión, y a una sintomatología depresiva e ideación suicida elevada. Los eventos traumáticos, el tratamiento farmacológico para la depresión y la severidad de la ideación suicida fueron predictores significativos del número de experiencias reportadas. Los resultados confirman que la mayoría de las experiencias no son psicóticas. Se discuten las implicaciones para la evaluación y el tratamiento de jóvenes deprimidos/as.

Ruthenium nanoparticles in ionic liquids: structural and stability effects of polar solutes.

PubMed

Salas, Gorka; Podgoršek, Ajda; Campbell, Paul S; Santini, Catherine C; Pádua, Agílio A H; Costa Gomes, Margarida F; Philippot, Karine; Chaudret, Bruno; Turmine, Mireille

2011-08-14

Ionic liquids are a stabilizing medium for the in situ synthesis of ruthenium nanoparticles. Herein we show that the addition of molecular polar solutes to the ionic liquid, even in low concentrations, eliminates the role of the ionic liquid 3D structure in controlling the size of ruthenium nanoparticles, and can induce their aggregation. We have performed the synthesis of ruthenium nanoparticles by decomposition of [Ru(COD)(COT)] in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [C(1)C(4)Im][NTf(2)], under H(2) in the presence of varying amounts of water or 1-octylamine. For water added during the synthesis of metallic nanoparticles, a decrease of the solubility in the ionic liquid was observed, showed by nanoparticles located at the interface between aqueous and ionic phases. When 1-octylamine is present during the synthesis, stable nanoparticles of a constant size are obtained. When 1-octylamine is added after the synthesis, aggregation of the ruthenium nanoparticles is observed. In order to explain these phenomena, we have explored the molecular interactions between the different species using (13)C-NMR and DOSY (Diffusional Order Spectroscopy) experiments, mixing calorimetry, surface tension measurements and molecular simulations. We conclude that the behaviour of the ruthenium nanoparticles in [C(1)C(4)Im][NTf(2)] in the presence of 1-octylamine depends on the interaction between the ligand and the nanoparticles in terms of the energetics but also of the structural arrangement of the amine at the nanoparticle's surface.

Structure and dynamics of propylammonium nitrate-acetonitrile mixtures: An intricate multi-scale system probed with experimental and theoretical techniques.

PubMed

Campetella, Marco; Mariani, Alessandro; Sadun, Claudia; Wu, Boning; Castner, Edward W; Gontrani, Lorenzo

2018-04-07

In this article, we report the study of structural and dynamical properties for a series of acetonitrile/propylammonium nitrate mixtures as a function of their composition. These systems display an unusual increase in intensity in their X-ray diffraction patterns in the low-q regime, and their 1 H-NMR diffusion-ordered NMR spectroscopy (DOSY) spectra display unusual diffusivities. However, the magnitude of both phenomena for mixtures of propylammonium nitrate is smaller than those observed for ethylammonium nitrate mixtures with the same cosolvent, suggesting that the cation alkyl tail plays an important role in these observations. The experimental X-ray scattering data are compared with the results of molecular dynamics simulations, including both ab initio studies used to interpret short-range interactions and classical simulations to describe longer range interactions. The higher level calculations highlight the presence of a strong hydrogen bond network within the ionic liquid, only slightly perturbed even at high acetonitrile concentration. These strong interactions lead to the symmetry breaking of the NO 3 - vibrations, with a splitting of about 88 cm -1 in the ν 3 antisymmetric stretch. The classical force field simulations use a greater number of ion pairs, but are not capable of fully describing the longest range interactions, although they do successfully account for the observed concentration trend, and the analysis of the models confirms the nano-inhomogeneity of these kinds of samples.

Structure and dynamics of propylammonium nitrate-acetonitrile mixtures: An intricate multi-scale system probed with experimental and theoretical techniques

NASA Astrophysics Data System (ADS)

Campetella, Marco; Mariani, Alessandro; Sadun, Claudia; Wu, Boning; Castner, Edward W.; Gontrani, Lorenzo

2018-04-01

In this article, we report the study of structural and dynamical properties for a series of acetonitrile/propylammonium nitrate mixtures as a function of their composition. These systems display an unusual increase in intensity in their X-ray diffraction patterns in the low-q regime, and their 1H-NMR diffusion-ordered NMR spectroscopy (DOSY) spectra display unusual diffusivities. However, the magnitude of both phenomena for mixtures of propylammonium nitrate is smaller than those observed for ethylammonium nitrate mixtures with the same cosolvent, suggesting that the cation alkyl tail plays an important role in these observations. The experimental X-ray scattering data are compared with the results of molecular dynamics simulations, including both ab initio studies used to interpret short-range interactions and classical simulations to describe longer range interactions. The higher level calculations highlight the presence of a strong hydrogen bond network within the ionic liquid, only slightly perturbed even at high acetonitrile concentration. These strong interactions lead to the symmetry breaking of the NO3 - vibrations, with a splitting of about 88 cm-1 in the ν3 antisymmetric stretch. The classical force field simulations use a greater number of ion pairs, but are not capable of fully describing the longest range interactions, although they do successfully account for the observed concentration trend, and the analysis of the models confirms the nano-inhomogeneity of these kinds of samples.

[The course of pregnancy in congenital thyroid gland aplasia. Case report with special reference to maternal hypothyroidism].

PubMed

Bolz, M; Nagel, H

1994-01-01

A report is given on a 28 years old women with congenital aplasia of the thyroid gland. She was substituted with thyroxine (300 micrograms per day). Her first pregnancy was complicated by gestational hypertension and pre-eclampsia. Delivery was by forceps. During the first trimester of her second pregnancy, bleedings occurred. The thyroid-stimulating hormone level (TSH-level) was increased (18.3 microU/ml). The patient did not show clinical signs of manifested hypothyroidism. The thyroxine dosis was increased. Bleedings disappeared. Labour was terminated and induced. Labour intra partum was hypoactive. The delivery was again by forceps. The newborn did not show any signals of hypothyroidism. Dysfunction of thyroid gland is associated with reduced fertility. Hypothyroidism in pregnancy is associated with an adverse outcome in fetal health as well as an increase in obstetric complications. Thyroid hormones play a vital role in fetal development and maturation of brain. Women with a hypothyroidism have a lower rate of pregnancy and a higher rate of spontaneous miscarriages compared to a normal population. Recognition and treatment of thyroid disorders in reproductive age occur before conception. Iodoprophylaxis is necessary for prevention of congenital hypothyroidism (cretinism). Iodoprophylaxis is necessary to prevent endemic goiter in pregnancy. Euthyroid goiter is an indication for a combined treatment with jodid and levothyroxine. Treatment should be individualized. Assessment of efficacy of treatment is based on measurement of TSH- and free thyroid hormone (fT4)-levels.

Investigating the Interaction Pattern and Structural Elements of a Drug-Polymer Complex at the Molecular Level.

PubMed

Nie, Haichen; Mo, Huaping; Zhang, Mingtao; Song, Yang; Fang, Ke; Taylor, Lynne S; Li, Tonglei; Byrn, Stephen R

2015-07-06

Strong associations between drug and polymeric carriers are expected to contribute to higher drug loading capacities and better physical stability of amorphous solid dispersions. However, molecular details of the interaction patterns and underlying mechanisms are still unclear. In the present study, a series of amorphous solid dispersions of clofazimine (CLF), an antileprosy drug, were prepared with different polymers by applying the solvent evaporation method. When using hypromellose phthalate (HPMCP) as the carrier, the amorphous solid dispersion system exhibits not only superior drug loading capacity (63% w/w) but also color change due to strong drug-polymer association. In order to further explain these experimental observations, the interaction between CLF and HPMCP was investigated in a nonpolar volatile solvent system (chloroform) prior to forming the solid dispersion. We observed significant UV/vis and (1)H NMR spectral changes suggesting the protonation of CLF and formation of ion pairs between CLF and HPMCP in chloroform. Furthermore, nuclear Overhauser effect spectroscopy (NOESY) and diffusion order spectroscopy (DOSY) were employed to evaluate the strength of associations between drug and polymers, as well as the molecular mobility of CLF. Finally, by correlating the experimental values with quantum chemistry calculations, we demonstrate that the protonated CLF is binding to the carboxylate group of HPMCP as an ion pair and propose a possible structural model of the drug-polymer complex. Understanding the drug and carrier interaction patterns from a molecular perspective is critical for the rational design of new amorphous solid dispersions.

Unprecedented Spectroscopic and Computational Evidence for Allenyl and Propargyl Titanocene(IV) Complexes: Electrophilic Quenching of Their Metallotropic Equilibrium.

PubMed

Ruiz-Muelle, Ana Belén; Oña-Burgos, Pascual; Ortuño, Manuel A; Oltra, J Enrique; Rodríguez-García, Ignacio; Fernández, Ignacio

2016-02-12

The synthesis and structural characterization of allenyl titanocene(IV) [TiClCp2 (CH=C=CH2 )] 3 and propargyl titanocene(IV) [TiClCp2 (CH2 -C≡C-(CH2 )4 CH3 )] 9 have been described for the first time. Advanced NMR methods including diffusion NMR methods (diffusion pulsed field gradient stimulated spin echo (PFG-STE) and DOSY) have been applied and established that these organometallics are monomers in THF solution with hydrodynamic radii (from the Stokes-Einstein equation) of 3.5 and 4.1 Å for 3 and 9, respectively. Full (1) H, (13) C, Δ(1) H, and Δ(13) C NMR data are given, and through the analysis of the Ramsey equation, the first electronic insights into these derivatives are provided. In solution, they are involved in their respective metallotropic allenyl-propargyl equilibria that, after quenching experiments with aromatic and aliphatic aldehydes, ketones, and protonating agents, always give the propargyl products P (when carbonyls are employed), or allenyl products A (when a proton source is added) as the major isomers. In all the cases assayed, the ratio of products suggests that the metallotropic equilibrium should be faster than the reactions of 3 and 9 with electrophiles. Indeed, DFT calculations predict lower Gibbs energy barriers for the metallotropic equilibrium, thus confirming dynamic kinetic resolution. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Photoinduced electron transfer across a molecular wall: coumarin dyes as donors and methyl viologen and TiO2 as acceptors.

PubMed

Porel, Mintu; Klimczak, Agnieszka; Freitag, Marina; Galoppini, Elena; Ramamurthy, V

2012-02-21

Coumarins C-153, C-480, and C-1 formed 1:2 (guest:host) complexes with a water-soluble cavitand having eight carboxylic acid groups (OA) in aqueous borate buffer solution. The complexes were photoexcited in the presence of electron acceptors (methyl viologen, MV(2+), or TiO(2)) to probe the possibility of electron transfer between a donor and an acceptor physically separated by a molecular wall. In solution at basic pH, the dication MV(2+) was associated to the exterior of the complex C-153@OA(2), as suggested by diffusion constants (~1.2 × 10(-6) cm(2)/s) determined by DOSY NMR. The fluorescence of C-153@OA(2) was quenched in the presence of increasing amounts of MV(2+) and Stern-Volmer plots of I(o)/I and τ(o)/τ vs [MV(2+)] indicated that the quenching was static. As per FT-IR-ATR spectra, the capsule C-153@OA(2) was bound to TiO(2) nanoparticle films. Selective excitation (λ(exc) = 420) of the above bound complex resulted in fluorescence quenching. When adsorbed on insulating ZrO(2) nanoparticle films, excitation of the complex resulted in a broad fluorescence spectrum centered at 500 nm and consistent with C-153 being within the lipophilic capsule interior. Consistent with the above results, colloidal TiO(2) quenched the emission while colloidal ZrO(2) did not.

Modern Radiobiology: Contention Of Concepts: Advanced Technology And Development Of Effective Prophylaxis, Prevention And Treatment Of Biological Consequences After Irradiation.

NASA Astrophysics Data System (ADS)

Popov, Dmitri; Maliev, Vecheslav; Jones, Jeffrey

"Alle Ding' sind Gift, und nichts ohn' Gift; allein die Dosis macht, daß ein Ding kein Gift ist." Paracelsus Philippus Aureolus Theophrastus Bombastus von Hohenheim. Key worlds: Apoptosis, Necrosis, Domains associated with Cell Death, Caspase (catalytic) Domains, Death Domains (DDs), Death Effector Domains (DEDs), Caspase-Associated Recruitment Domains (CARDs, BIR Domains (IAPs), Bcl-2 Homology (BH) Domains, death ligands - TRAIL (TNF-Related Apoptosis-Inducing Ligand), FasL (Fas Ligand), TNFalpha (Tumor Necrosis Factor alpha), Toll-like receptors (TLR), Systemic inflammatory response syndrome (SIRS), Toxic Multiple Organ Injury (TMOI), Toxic Multiple Organ Dysfunction Syndromes (TMODS), Toxic Multiple Organ Failure (TMOF), Anaphylatoxins, or complement peptides; membrane attack complex (MAC), ROS - Reactive Oxygen Species; ASMase, acid sphingomyelinase; Neurotoxins, Cytotoxins, Haemotoxins. Introduction: Radiation affects many cell structures, organelles and metabolic pathways. Different doses and types of radiation ( gamma-radiation, neutron, heavy ion radiation) progress to reversible and irreversible forms of cell injury. Consideration: Apoptosis and Necrosis, major forms of post-radiation cell death, can be initiated and modulated by programmed control and proceed by similar or different pathways.[Akadi et al.,1993, Dunlacht J., et al. 1999] Radiation induced cell death by triggering apoptosis pathways was described in many articles and supported by many scientists. [Rio et al. 2002, Rakesh et al. 1997.] However some authors present results that two distinct pathways can initiate or apoptotic or necrotic responses: the death receptors and mitochondrial pathways.

Direct metabolic fingerprinting of commercial herbal tinctures by nuclear magnetic resonance spectroscopy and mass spectrometry.

PubMed

Politi, Matteo; Zloh, Mire; Pintado, Manuela E; Castro, Paula M L; Heinrich, Michael; Prieto, Jose M

2009-01-01

Tinctures are widely used liquid pharmaceutical preparations traditionally obtained by maceration of one or more medicinal plants in ethanol-water solutions. Such a process results in the extraction of virtually hundreds of structurally diverse compounds with different polarities. Owing to the large chemical diversity of the constituents present in the herbal tinctures, the analytical tools used for the quality control of tinctures are usually optimised only for the detection of single chemical entities or specific class of compounds. In order to overcome the major limitations of the current methods used for analysis of tinctures, a new methodological approach based on NMR spectroscopy and MS spectrometry has been tested with different commercial tinctures. Diffusion-edited 1H-NMR (1D DOSY) and 1H-NMR with suppression of the ethanol and water signals have been applied here for the first time to the direct analysis of commercial herbal tinctures derived from Echinacea purpurea, Hypericum perforatum, Ginkgo biloba and Valeriana officinalis. The direct injection of the tinctures in the MS detector in order to obtain the corresponding metabolic profiles was also performed. Using both NMR and MS methods it was possible, without evaporation or separation steps, to obtain a metabolic fingerprint able to distinguish between tinctures prepared with different plants. Batch-to-batch homogeneity, as well as degradation after the expiry date of a batch, was also investigated. The techniques proposed here represent fast and convenient direct analyses of medicinal herbal tinctures.

Medición de los parámetros cosmológicos q0, ΩM, y ΩΛ, usando supernovas de Tipo Ia distantes

NASA Astrophysics Data System (ADS)

Clocchiatti, A.; High-Z Sne Search Team

Las supernovas de tipo Ia son una herramienta de gran precisión para la medición de distancias de interés cosmológico. Los métodos recientes de calibración de su luminosidad intrínseca, que hacen uso de la forma de las curvas de luz en varios colores y permiten diferenciar entre supernovas distantes, intrínsecamente débiles, u oscurecidas por extinción, reducen la dispersión del método que las asume de magnitud absoluta constante de 0.50 mag a 0.15 mag, e incrementa el valor de la constante de Hubble de ~55 km s-1 Mpc-1, a 65 km s-1 Mpc-1. A partir de la calibración de las supernovas cercanas, con redshifts menores que 0.1, se pueden obtener distancias precisas a supernovas que explotan a alto redshift. Hemos aplicado estos métodos a 16 supernovas con 0.16 < Z < 0.97, encontrando que sus distancias son, en promedio, entre 10% y 13% (dependiendo del método empleado) mayores que las que uno esperaría en un universo con poca masa (Ω = 0.2), sin una constante cosmológica. Todos los métodos de ajuste de curvas de luz, y selección de subgrupos de la muestra de supernovas observadas, favorecen consistentemente modelos del universo que se expanden eternamente y que tienen una constante cosmológica positiva (ΩΛ > 0), y una aceleración de la expansión al presente (q0 < 0). Hay distintas fuentes de posibles errores sistemáticos que merecen ser analizadas, entre ellas: evolución de la metalicidad y estrellas progenitoras, extinción, bias en la elección de la muestra, amplificación por gravitational lensing, y contaminación de la muestra. Ninguno de estos efectos alcanza para reconciliar los datos con ΩΛ = 0, o q0 > 0.

Coordination-Driven Dimerization of Zinc Chlorophyll Derivatives Possessing a Dialkylamino Group.

PubMed

Watanabe, Hiroaki; Kamatani, Yusuke; Tamiaki, Hitoshi

2017-04-04

Zinc chlorophyll derivatives Zn-1-3 possessing a tertiary amino group at the C3 1 position have been synthesized through reductive amination of methyl pyropheophorbide-d obtained from naturally occurring chlorophyll-a. In a dilute CH 2 Cl 2 solution as well as in a dilute 10 %(v/v) CH 2 Cl 2 /hexane solution, Zn-1 possessing a dimethylamino group at the C3 1 position showed red-shifted UV/Vis absorption and intensified exciton-coupling circular dichroism (CD) spectra at room temperature owing to its dimer formation via coordination to the central zinc by the 3 1 -N atom of the dimethylamino group. However, Zn-2/3 bearing 3 1 -ethylmethylamino/diethylamino groups did not. The difference was dependent on the steric factor of the substituents in the tertiary amino group, where an increase of the carbon numbers on the N atom reduced the intermolecular N⋅⋅⋅Zn coordination. UV/Vis, CD, and 1 H NMR spectroscopic analyses including DOSY measurements revealed that Zn-1 formed closed-type dimers via an opened dimer by single-to-double axial coordination with an increase in concentration and a temperature decrease in CH 2 Cl 2 , while Zn-2/3 gave open and flexible dimers in a concentrated CH 2 Cl 2 solution at low temperature. The supramolecular closed dimer structures of Zn-1 were estimated by molecular modelling calculations, which showed these structures were promising models for the chlorophyll dimer in a photosynthetic reaction center. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Challenges in the Structure Determination of Self-Assembled Metallacages: What Do Cage Cavities Contain, Internal Vapor Bubbles or Solvent and/or Counterions?

PubMed

Givelet, Cecile C; Dron, Paul I; Wen, Jin; Magnera, Thomas F; Zamadar, Matibur; Čépe, Klára; Fujiwara, Hiroki; Shi, Yue; Tuchband, Michael R; Clark, Noel; Zbořil, Radek; Michl, Josef

2016-05-25

Proving the structures of charged metallacages obtained by metal ion coordination-driven solution self-assembly is challenging, and the common use of routine NMR spectroscopy and mass spectrometry is unreliable. Carefully determined diffusion coefficients from diffusion-ordered proton magnetic resonance (DOSY NMR) for six cages of widely differing sizes lead us to propose a structural reassignment of two molecular cages from a previously favored trimer to a pentamer or hexamer, and another from a trimer to a much higher oligomer, possibly an intriguing tetradecamer. In the former case, strong support for the reassignment to a larger cage is provided by an observation of a slow reversible transformation of the initially formed cage into a smaller but spectrally very similar one upon dilution. In the latter case, freeze-fracture transmission electron micrographs demonstrate that at least some of the solutions are colloidal, and high-resolution electron transmission and atomic force microscopy images are compatible with a tetradecamer but not a trimer. Comparison of solute partial molar volumes deduced from measurement of solution density with volumes anticipated from molecular models argues strongly against the presence of large voids (solvent vapor bubbles) in cages dissolved in nitromethane. The presence of bubbles was previously proposed in an attempt to account for the bilinear nature of the Eyring plot of the rate constant for pyridine ligand edge exchange reaction in one of the cages and for the unusual activation parameters in the high-temperature regime. An alternative interpretation is proposed now.

Sentinel-Lymphknoten-Biopsie des Melanoms mittels Indocyaningrün und "FOVIS"-System.

PubMed

Göppner, Daniela; Nekwasil, Stephan; Jellestad, Anne; Sachse, Alexander; Schönborn, Karl-Heinz; Gollnick, Harald

2017-02-01

Der Nachweis metastatischer Infiltrate im Sentinel-Lymphkoten (SLN) gilt als wesentlicher prognostischer Faktor des Melanoms. Alternativ zur Farbstoffmethode mit Patentblau zum Goldstandard der SLN-Biopsie (SLNB) mittels Radiokolloid wird die fluoreszenzoptische Darstellung mit Hilfe von Indocyaningrün (ICG) und Nahinfrarot (NIR)-Kamerasystem kommuniziert. Im Vergleich zur konventionellen Methode wurde die Wertigkeit des ICG-/NIR-Verfahrens in Abhängigkeit vom Body-Mass-Index (BMI) des Patienten und der Konzentration von ICG bezüglich der Visualisierung des Lymphabstroms und des SLNs untersucht. An zehn Patienten wurde die SLNB mittels Technetium-99m, Patentblau und ICG durchgeführt. Die Fluoreszenz-Darstellung von Lymphbahnen und SLN erfolgte in Echtzeit mittels der NIR-Kameratechnik "FOVIS". Je nach erzielter Bildqualität wurde ICG in einer Dosis von 0,25 mg bis 2,5 mg intrakutan appliziert. Neun der zehn SLN wurden fluoreszenzoptisch identifiziert (90 %), alle zehn radioaktiv (100 %), nur acht (80 %) mittels ICG-Grünfärbung bzw. Patenblau-Markierung. Transdermal wurde ein SLN dargestellt (10 %). In Korrelation zum BMI waren höhere ICG-Mengen, bis zu 2,5 mg intrakutan absolut, in der Darstellung der Lymphbahnen von Vorteil. Die SLN-Fluoreszenzmarkierung mit dem ICG/NIR-Kamera-System "FOVIS" stellt eine sichere Alternative zur Farbstoffmethode mit Patentblau ergänzend zur Radiokolloidmethode mit Technetium-99m dar. Weitere Studien zur optimalen Dosierung von ICG und transdermalen Bildgebung in Relation zum BMI sind notwendig. © 2017 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Precursor Ion–Ion Aggregation in the Brust–Schiffrin Synthesis of Alkanethiol Nanoparticles

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

Graham, Trent R.; Renslow, Ryan; Govind, Niranjan

Tetraoctylammonium bromide is used in the Brust-Schiffrin nanoparticle synthesis to phase-transfer chloroaurate ions from the aqueous phase to the organic phase. While it is established that the quaternary ammonium complex self-associates in the organic phase, the actual self-assembled structure is debated. We have confirmed the presence of ion-ion aggregates through quantitative 1H Nuclear Magnetic Resonance spectroscopy (NMR), pulsed field gradient, diffusion-ordered NMR (DOSY-NMR) and density functional theory (DFT) based NMR shift calculations. Tetraoctylammonium complexes (TOA-X, where X = Br, Cl, AuCl4-xBrx, AuBr4/Br and AuCl4-xBrx/Br) were investigated to measure the extraction of water into the organic phase. 1H NMR and DFTmore » based NMR shielding calculations indicated that deshielding of water is due to hydration of the anion and not the formation of the aqueous core of a reverse micelle. DOSYNMR results were consistent with the formation of small aggregates at typical Brust-Schiffrin synthesis concentrations. The extent of aggregation correlated with the size and electronegativity of the anion and was analyzed with a modified, isodesmic, indefinite aggregation model. The substitution of bromoauric acid for chlororoauric acid at conditions emulating the Brust-Schiffrin synthesis increased the aggregation of the quaternary ammonium complex. The increase in aggregation corresponded with an increase in the size of the produced nanoparticles from 4.3 to 4.6 nm. Understanding the selfassembly and supramolecular structure of precursors in the Brust-Schiffrin synthesis will enable further refinement of models that predict the growth of noble metal nanoparticles.« less

Computational Metabolomics: A Framework for the Million Metabolome

PubMed Central

Uppal, Karan; Walker, Douglas I.; Liu, Ken; Li, Shuzhao; Go, Young-Mi; Jones, Dean P.

2017-01-01

“Sola dosis facit venenum.” These words of Paracelsus, “the dose makes the poison”, can lead to a cavalier attitude concerning potential toxicities of the vast array of low abundance environmental chemicals to which humans are exposed. Exposome research teaches that 80–85% of human disease is linked to environmental exposures. The human exposome is estimated to include >400,000 environmental chemicals, most of which are uncharacterized with regard to human health. In fact, mass spectrometry measures >200,000 m/z features (ions) in microliter volumes derived from human samples; most are unidentified. This crystallizes a grand challenge for chemical research in toxicology: to develop reliable and affordable analytical methods to understand health impacts of the extensive human chemical experience. To this end, there appears to be no choice but to abandon the limitations of measuring one chemical at a time. The present review looks at progress in computational metabolomics to provide probability based annotation linking ions to known chemicals and serve as a foundation for unambiguous designation of unidentified ions for toxicologic study. We review methods to characterize ions in terms of accurate mass m/z, chromatographic retention time, correlation of adduct, isotopic and fragment forms, association with metabolic pathways and measurement of collision-induced dissociation products, collision cross section, and chirality. Such information can support a largely unambiguous system for documenting unidentified ions in environmental surveillance and human biomonitoring. Assembly of this data would provide a resource to characterize and understand health risks of the array of low-abundance chemicals to which humans are exposed. PMID:27629808

Evaluating intra- and inter- sample variability in Electron Spin Resonance dating of fossil teeth: an example from Cuesta de la Bajada site (Spain).

NASA Astrophysics Data System (ADS)

Duval, Mathieu; Grün, Rainer; Shao, Qingfeng; Martin, Loïc; Arnold, Lee J.

2017-04-01

Over the last decades, technological improvements have progressively enabled to significantly decrease the amount of material required for dating analyses. In particular, the combined use of laser ablation (LA) with ICP-MS opened new possibilities for high resolution in situ U-series analyses of fossil teeth. With this technique it is now possible to directly visualise the spatial distribution of U and Th isotopes in dental tissues. Moreover, the combination of LA-ICP-MS with Electron Spin Resonance (ESR) enables an increased sampling resolution, and offers the possibility to produce several ages for different areas within a given fossil tooth. To test the potential of this new approach, several fossil teeth were collected from the Middle Palaeolithic site of Cuesta de la Bajada (Teruel, Spain). Each tooth was divided into several subsamples, providing thus several combined US-ESR age results per tooth. For each subsample, ESR, high-resolution laser ablation and solution ICP-MS U-series analyses were systematically performed. Relative beta dose rate contributions from the different tissues and the sediment were also adjusted using DosiVox software and compared with those derived from the standard approach. The results of this work give some interesting insight into the intra- and inter- sample variability that may exist at a given site. The consistency of the final US-ESR age estimates obtained on teeth are also evaluated by comparison with the (semi)-independent results derived from ESR and Luminescence dating of optically bleached quartz grains collected from the same excavation area.

Hydrophobic effect as a driving force for host-guest chemistry of a multi-receptor Keplerate-type capsule.

PubMed

Watfa, Nancy; Melgar, Dolores; Haouas, Mohamed; Taulelle, Francis; Hijazi, Akram; Naoufal, Daoud; Avalos, Josep Bonet; Floquet, Sébastien; Bo, Carles; Cadot, Emmanuel

2015-05-06

The effectiveness of the interactions between various alkylammonium cations and the well-defined spherical Keplerate-type {Mo132} capsule has been tracked by (1)H DOSY NMR methodology, revealing a strong dependence on the self-diffusion coefficient of the cationic guests balanced between the solvated and the plugging situations. Analysis of the data is fully consistent with a two-site exchange regime involving the 20 independent {Mo9O9} receptors of the capsule. Furthermore, quantitative analysis allowed us to determine the stability constants associated with the plugging process of the pores. Surprisingly, the affinity of the capsule for a series of cationic guests increases continuously with its apolar character, as shown by the significant change of the stability constant from 370 to 6500 for NH4(+) and NEt4(+), respectively. Such observations, supported by the thermodynamic parameters, evidence that the major factor dictating selectivity in the trapping process is the so-called "hydrophobic effect". Computational studies, using molecular dynamics simulations, have been carried out in conjunction with the experiments. Analysis of the radial distribution functions g(r) reveals that NH4(+) and NMe4(+) ions behave differently in the vicinity of the capsule. The NH4(+) ions do not exhibit well-defined distributions when in close vicinity. In contrast, the NMe4(+) ions displayed sharp distributions related to different scenarios, such as firmly trapped or labile guest facing the {Mo9O9} pores. Together, these experimental and theoretical insights should aid in the exploitation of these giant polyoxometalates in solution for various applications.

Tunable Keplerate Type-Cluster "Mo132 " Cavity with Dicarboxylate Anions.

PubMed

Lai, Thanh-Loan; Awada, Mouhamad; Floquet, Sébastien; Roch-Marchal, Catherine; Watfa, Nancy; Marrot, Jérôme; Haouas, Mohamed; Taulelle, Francis; Cadot, Emmanuel

2015-09-14

The internal functionalization of the Keplerate-type capsule Mo132 has been carried out by ligand exchange leading to the formation of glutarate and succinate containing species isolated as ammonium or dimethylammonium salts. Solution NMR analysis is consistent with asymmetric inner dicarboxylate ions containing one carboxylato group grafted onto the inner side of the spheroidal inorganic shell while the second hangs toward the center of the cavity. Such a disposition has been confirmed by the single-crystal X-ray diffraction analysis of the glutarate containing {Mo132 } species. A detailed NMR solution study of the ligand-exchange process allowed determining the binding constant KL of acetate (AcO(-) ), succinate (HSucc(-) ) or glutarate (HGlu(-) ) ligands at the 30 inner coordinating sites, which vary such as K AcO -

Characterization of γ-radiation induced polymerization in ethyl methacrylate and methyl acrylate monomers solutions

NASA Astrophysics Data System (ADS)

Baccaro, Stefania; Casieri, Cinzia; Cemmi, Alessia; Chiarini, Marco; D'Aiuto, Virginia; Tortora, Mariagrazia

2017-12-01

The present work is focused on the γ-radiation induced polymerization of ethyl methacrylate (EMA) and methyl acrylate (MA) monomers mixture to obtain a co-polymer with specific features. The effect of the irradiation parameters (radiation absorbed dose, dose rate) and of the environmental atmosphere on the features of the final products was investigated. Attenuated Total Reflectance - Fourier Transform Infrared Spectroscopy (ATR-FTIR) and Nuclear Magnetic Resonance high-resolution analyses of hydrogen and carbon nuclei (1H and 13C NMR) were applied to follow the γ-induced modifications by monitoring the co-polymerization process and allowed the irradiation parameters optimization. Diffusion-Ordered NMR (DOSY-NMR) data were used to evaluate the co-polymers polydispersity and polymerization degree. Since the last parameter is strongly influenced by the γ radiation and environmental conditions, a comparison among samples prepared and irradiated in air and under nitrogen atmosphere was carried out. In presence of oxygen, higher radiation was required to obtain a full solid co-polymer since a partial amount of energy released to the samples was involved in competitive processes, i.e. oxygen-containing free radicals formation and primary radicals recombination. Irrespectively to the environmental atmosphere, more homogeneous samples in term of polymerization degree dispersion was achieved at lower dose rates. At radiation absorbed doses higher than those needed for the formation of the co-polymer, while in case of samples irradiated in air heavy depolymerization was verified, a sensible increase of the samples stability was attained if the irradiation was performed under nitrogen atmosphere.

[Premature birth in patient with cervix incompetence and history of myasthenia gravis].

PubMed

Fuentealba, Maximiliano; Troncoso, Miguel; Vallejos, Joaquin; Ponce, Sebastian; Villablanca, Nelson; Melita, Pablo

2013-09-01

Cervical incompetence it's a dilatation of the cervix during the third trimester of pregnancy that ends with the interruption of it. The incidence in Chile is about 0.1-2% of the total pregnancies and it's one of the causes of preterm birth. A 34 years old pregnant patient. Timectomized at age 18 to treat her miastenia gravis, previously trated with medication, had 4 previous preterm labours all of them under 25 weeks and vaginal births. All fetuses died postpartum. A cerclage was made during the third, fourth and fifth pregnancies. She didn't present hypertension during the gestation and no cervical diameter under 15mm. Since the fourth gestation the following tests are taken: Antifosfolipidic antibodies, APTT,PT. All the results are either normal or negative. Microbial cultures were negative. No amniocentesis was made. A McDonald cervical cerclage was made during pregnancies number 3, 4 and 5 on the 16th week to delay the labor. Also oral micronized progesterone, on a 400mg/24 hours dosis, was administered to avoid preterm birth. On the 24th week the pharmacological treatment started including Intramuscular Betamethasone, 12 mg/24 hours (2 doses), to induce lung maturity on the fetus. It is thought that the administration of progesterone could have improved the situation of the patient, because it acts as a labour repressants. The use of cerclage could have helped, but the factors that may influence the effectiveness of this method are unknown. Perhaps there is some immunologic factor associated with the miastenia gravis that alters the normal course of pregnancy.

Noncommunicable diseases and the use of health services: analysis of the National Health Survey in Brazil.

PubMed

Malta, Deborah Carvalho; Bernal, Regina Tomie Ivata; Lima, Margareth Guimarães; Araújo, Silvânia Suely Caribé de; Silva, Marta Maria Alves da; Freitas, Maria Imaculada de Fátima; Barros, Marilisa Berti de Azevedo

2017-06-01

To assess whether sex, education level, and health insurance affect the use of health services among the adult Brazilian population with chronic noncommunicable diseases (NCD). Data from a cross-sectional survey were analyzed, the National Health Survey (PNS). Frequency of use of services in the population that referred at least one NCD were compared with the frequency from a population that did not report NCD, according to sex, education level, health insurance, and NCD number (1, 2, 3, 4, or more). The prevalence and prevalence ratios were calculated crude and adjusted for sex, age, region, and 95% confidence intervals. The presence of a noncommunicable disease was associated with increase in hospitalizations in the last 12 months, in 1.7 times (95%CI 1.53-1.9). Failing to perform usual activities in the last two weeks for health reasons was 3.1 times higher in NCD carriers (95%CI 2.78-3.46); while the prevalence of medical consultation in the last 12 months was 1.26 times higher (95%CI 1.24-1.28). NCD carriers make more use of health services, as well as women, people with higher number of comorbidities, with health insurance, and higher education level. NCD carriers make more use of health services, as well as women, people with higher number of comorbidities, with health insurance, and higher education level. Analisar se sexo, escolaridade e posse de plano de saúde influenciam a utilização de serviços de saúde entre a população adulta brasileira portadora de doenças crônicas não transmissíveis (DCNT). Foram analisados dados de inquérito transversal, a Pesquisa Nacional de Saúde (PNS). Foram comparadas as frequências de uso de serviços na população que referiu pelo menos uma DCNT, com aquelas que não relatam DCNT, segundo sexo, escolaridade, posse de plano de saúde e número de DCNT (1, 2, 3, 4 ou mais). Foram calculadas as prevalências e razões de prevalência (RP) brutas e ajustadas por sexo, idade e região e respectivos intervalos de confiança de 95%. A presença de doença crônica associou-se ao aumento de internação nos últimos 12 meses, em 1,7 vezes (IC95% 1,53-1,9). Deixar de realizar atividades habituais nas duas últimas semanas por motivo de saúde foi 3,1 vezes maior em portadores de DCNT (IC95% 2,78-3,46), e a prevalência de consulta médica nos últimos 12 meses foi 1,26 vezes maior (IC95% 1,24-1,28). Portadores de DCNT utilizam mais os serviços de saúde, assim como as mulheres, pessoas com maior número de DCNT, com planos de saúde e elevada escolaridade. Portadores de DCNT têm maior utilização de serviços de saúde, assim como as mulheres, pessoas com maior número de comorbidades, com planos de saúde e elevada escolaridade.

Study and optimization of the macroscopic electrical response of carbon based nanocomposites for advanced applications

NASA Astrophysics Data System (ADS)

Silva, Jaime Pedro Oliveira da

A presente tese centrou-se no estudo da resposta da constante dieletrica e condutividade eletrica em materiais compositos nos quais o reforco tinha uma elevada proporcao entre comprimento e diametro. O objeto de estudo foi o efeito de um reforco com uma elevada razao entre comprimento e diametro, concentracao e orientacao na resposta eletrica e dieletrica de um composito. Estes compositos tem uma grande importancia no desenvolvimento de materiais para sensores e atuadores. Num primeiro momento da dissertacao, explorou-se a resposta da constante dieletrica de um composito constituido por nanotubos de carbono como reforco e uma matriz polimerica. Verificou-se que um aumento da razao entre comprimento e diametro do reforco tem o efeito de aumentar a constante dieletrica do composito para uma igual fracao volumetrica de reforco. Constatou-se tambem que materiais na fase nematica demonstram uma constante dieletrica mais baixa quando comparados com materiais onde o reforco esta distribuido aleatoriamente. Ficou ainda demonstrado nesta dissertacao que materiais na fase nematica com razoes entre o comprimento e diametro diferentes a constante dieletrica segue uma lei de potencia. Numa segunda fase do trabalho, foi explorada a condutividade de nanocompositos polimericos reforcados com nanotubos de carbono, atraves de um modelo baseado em cilindros impenetraveis. Ficou demonstrado que o modelo e apropriado para descrever a condutividade eletrica de um nanocomposito polimerico reforcado com nanotubos. As simulacoes desenvolvidas demonstram que, aumentando a razao entre o comprimento e o diametro dos nanotubos de carbono, aumenta a condutividade eletrica do nanocomposito. No entanto, verifica-se que aumentando a anisotropia diminui a condutividade, sendo este efeito mais evidente para fracoes volumetricas maiores. Nesta dissertacao comprovou-se ainda que uma microestrutura gerada por um algoritmo de empacotamento sequencial pode ser descrita por um grafo aleatorio e que a condutividade num composito reforcado com nanofibras de carbono pode ser descrito por uma rede de Bethe. Atraves do uso da teoria das redes complexas, chegou-se a uma expressao para o limite de percolacao e, do mesmo modo, demonstrou-se que “hopping” entre fibras adjacentes resulta numa expressao que corresponde a um regime de desordem fraca. No trabalho desenvolvido tambem foi calculado os expoentes criticos, atraves da teoria das redes, para um sistema 3D composto por cilindros impenetraveis com uma interacao de curto alcance, demonstrando que os expoentes criticos estao relacionados por uma relacao de hiperescala comum para 3D e nao pertencem a mesma classe de universalidade como a percolacao numa rede. A aplicacao do modelo desenvolvido a compositos de epoxy reforcada, com diferentes metodos de dispersao de nanofibras de carbono, revelou que os metodos de dispersao usados para preparar os compositos tem uma forte influencia nas propriedades eletricas que podem ser capturadas pelo modelo. Neste contexto, ficou ainda demonstrado que a condutividade eletrica pode ser descrita por um regime de desordem fraca, isto ´e, um regime onde todas as conexoes fibra-fibra participam na condutividade do composito. O modelo desenvolvido foi aplicado igualmente a compositos de poly (vinylidene fluoride) reforcado com nanotubos de carbono com diferentes tratamentos de termicos de oxidacao. Verificou-se que os tratamentos de superficie aumentam o limite de percolacao e diminuem a condutividade. Nesta dissertacao provamos ainda que a condutividade do composito pode ser atribuida a um mecanismo de “hopping”, fortemente afetado pelos tratamentos de superficie dos reforcos.

Development and validation of the Hospitality Axiological Scale for Humanization of Nursing Care.

PubMed

Galán González-Serna, José María; Ferreras-Mencia, Soledad; Arribas-Marín, Juan Manuel

2017-08-03

to develop and validate a scale to evaluate nursing attitudes in relation to hospitality for the humanization of nursing care. Participants: the sample consisted of 499 nursing professionals and undergraduate students of the final two years of the Bachelor of Science in Nursing program. the instrument has been developed and validated to evaluate the ethical values related to hospitality using a methodological approach. Subsequently, a model was developed to measure the dimensions forming the construct hospitality. the Axiological Hospitality Scale showed a high internal consistency, with Cronbach's Alpha=0.901. The validation of the measuring instrument was performed using factorial, exploratory and confirmatory analysis techniques with high goodness of fit measures. the developed instrument showed an adequate validity and a high internal consistency. Based on the consistency of its psychometric properties, it is possible to affirm that the scale provides a reliable measurement of the hospitality. It was also possible to determine the dimensions or sources that embrace it: respect, responsibility, quality and transpersonal care. desenvolver e validar uma escala que permita avaliar a atitude dos enfermeiros em termos de hospitalidade, visando a humanização da enfermagem.Participantes: a amostra foi constituída por 499 profissionais e estudantes de enfermagem dos dois últimos anos do curso de graduação em Enfermagem. utilizando-seuma abordagem metodológica, foi desenvolvido e validado um instrumento para avaliar os valores éticos relacionados com a hospitalidade. Subsequentemente, foi formulado um modelo para mediras dimensões que constituem o construto hospitalidade. a Escala Axiológica de Hospitalidade mostrou uma consistência interna elevada, com Alfa de Cronbach=0,901. A validação do instrumento de medição foi realizada usando-se métodos de análise fatorial, exploratória e confirmatória, que apresentaram bons índices de qualidade de ajuste. o instrumento desenvolvido apresentou uma validade adequada e uma consistência interna elevada. Com base na consistência de suas propriedades psicométricas, é possível afirmar que a escala proporciona uma medida confiável da hospitalidade. Também foi possível determinar as dimensões ou fontes que a compõem: o respeito, a responsabilidade, a qualidade e o cuidado transpessoal. desarrollar y validar una escala que permita evaluar la actitud enfermera ante la hospitalidad para la humanización de enfermería. Participantes: la muestra la componen 499 profesionales de enfermería y estudiantes de los dos últimos niveles académicos de la titulación de Grado en Enfermería. mediante abordaje metodológico, se ha desarrollado y validado un instrumento para evaluar valores éticos relacionados con la hospitalidad. Posteriormente, se ha formulado un modelo de medida de las dimensiones que conforman el constructo hospitalidad. la Escala Axiológica de la Hospitalidad ha mostrado una alta consistencia interna, con un Alfa de Cronbach=0.901. La validación del instrumento de medida se realizó mediante las técnicas de análisis factorial, exploratorio y confirmatorio, que presentaron unos buenos índices de bondad de ajuste. el instrumento desarrollado ha presentado una adecuada validez y una alta consistencia interna. Sus adecuadas propiedades psicométricas permiten afirmar que la escala aporta una medición fiable de la hospitalidad. También ha permitido determinar las dimensiones o fuentes que la conforman: el respeto, la responsabilidad, la calidad y el cuidado transpersonal.

Zeitlicher Verlauf der avaskulären Nekrose des Hüftkopfes bei Patienten mit Pemphigus vulgaris.

PubMed

Balighi, Kamran; Daneshpazhooh, Maryam; Aghazadeh, Nessa; Saeidi, Vahide; Shahpouri, Farzam; Hejazi, Pardis; Chams-Davatchi, Cheyda

2016-10-01

Pemphigus vulgaris (PV) wird in der Regel mit systemischen Corticosteroiden und Immunsuppressiva behandelt. Avaskuläre Nekrose (AVN) des Hüftkopfes ist eine gut bekannte schwerere Komplikation einer Corticosteroid-Therapie. Die Charakteristika dieser schweren Komplikation bei PV sind nach wie vor unbekannt. Nicht kontrollierte, retrospektive Untersuchung aller PV-bedingten AVN-Fälle, die in einer iranischen Klinik für bullöse Autoimmunerkrankungen zwischen 1985 und 2013 diagnostiziert wurden. Anhand der Krankenakten von 2321 untersuchten PV-Patienten wurden 45 Fälle (1,93 %) von femoraler AVN identifiziert. Dreißig davon waren Männer. Das mittlere Alter bei der Diagnose der AVN betrug 47,4 ± 14,2 Jahre. Der mittlere Zeitraum zwischen der Diagnose des PV und dem Einsetzen der AVN lag bei 25,3 ± 18,3 Monaten. Mit Ausnahme von acht Fällen (17,8 %) setzte die AVN bei der Mehrheit der Patienten innerhalb von drei Jahren nach Diagnose des PV ein. Die mittlere kumulative Dosis von Prednisolon bei Patienten mit AVN betrug 13.115,8 ± 7041,1 mg. Zwischen der Prednisolon-Gesamtdosis und dem Zeitraum bis zum Einsetzen der AVN bestand eine starke Korrelation (p = 0,001). Bei Patienten mit Alendronateinnahme in der Vorgeschichte war dieser Zeitraum signifikant kürzer (p = 0,01). Die AVN ist eine schwere Komplikation einer Corticosteroid-Behandlung bei Patienten mit PV. Sie wird bei 2 % der Patienten beobachtet und tritt vor allem in den ersten drei Behandlungsjahren auf. Bei Patienten, die höhere Dosen von Prednisolon erhalten, setzt die AVN tendenziell früher ein. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Structural studies of novel glycoconjugates from polymerized allergens (allergoids) and mannans as allergy vaccines.

PubMed

Manzano, Ana I; Javier Cañada, F; Cases, Bárbara; Sirvent, Sofia; Soria, Irene; Palomares, Oscar; Fernández-Caldas, Enrique; Casanovas, Miguel; Jiménez-Barbero, Jesús; Subiza, José L

2016-02-01

Immunotherapy for treating IgE-mediated allergies requires high doses of the corresponding allergen. This may result in undesired side effects and, to avoid them, hypoallergenic allergens (allergoids) polymerized with glutaraldehyde are commonly used. Targeting allergoids to dendritic cells to enhance cell uptake may result in a more effective immunotherapy. Allergoids coupled to yeast mannan, as source of polymannoses, would be suitable for this purpose, since mannose-binding receptors are expressed on these cells. Conventional conjugation procedures of mannan to proteins use oxidized mannan to release reactive aldehydes able to bind to free amino groups in the protein; yet, allergoids lack these latter because their previous treatment with glutaraldehyde. The aim of this study was to obtain allergoids conjugated to mannan by an alternative approach based on just glutaraldehyde treatment, taking advantage of the mannoprotein bound to the polymannose backbone. Allergoid-mannan glycoconjugates were produced in a single step by treating with glutaraldehyde a defined mixture of allergens derived from Phleum pratense grass pollen and native mannan (non-oxidized) from Saccharomyces cerevisae. Analytical and structural studies, including 2D-DOSY and (1)H-(13)C HSQC nuclear magnetic resonance spectra, demonstrated the feasibility of such an approach. The glycoconjugates obtained were polymers of high molecular weight showing a higher stability than the native allergen or the conventional allergoid without mannan. The allergoid-mannan glycoconjugates were hypoallergenic as detected by the IgE reactivity with sera from grass allergic patients, even with lower reactivity than conventional allergoid without mannan. Thus, stable hypoallergenic allergoids conjugated to mannan suitable for using in immunotherapy can be achieved using glutaraldehyde. In contrast to mannan oxidation, the glutaraldehyde approach allows to preserve mannoses with their native geometry, which may be functionally important for its receptor-mediated recognition.

PubMed

Scotta, Ana Verónica; Bongiovanni, Guillermina Azucena; Soria, Elio Andrés

2018-03-21

Antecedentes: Clorpirifos es un pesticida altamente tóxico, que puede producir inmunotoxicidad con efectos deletéreos sobre la salud a nivel mundial. Por otro lado, las plantas americanas pueden tener derivados con actividad protectora e inmunoestimulante. Por lo tanto, debe evaluarse el potencial de estas plantas frente a clorpirifos. Objetivo: Identificar extractos acuosos bioactivos de Lantana grisebachii (LG), Aspidosperma quebracho-blanco (AQ), Peumus boldus (PB), e Ilex paraguariensis (IP), contra la toxicidad de clorpirifos sobre esplenocitos de hembras Balb/c. Materiales y Métodos: Esplenocitos fueron tratados in vitro por 72 horas con 0-35 µg/mL de clorpirifos, 0-100 µg/mL de cada extracto (LG, AQ, PB, IP) y 0-5 µg/mL de concanavalina A. Luego, se midió y analizó estadísticamente viabilidad y muerte celular (tinciones de resazurina y yoduro de propidio), hidroperóxidos, lipoperóxidos (ensayos basados en naranja de xilenol), actividad de la ?-glutamiltranspeptidasa (método de Szasz). Resultados: Clorpirifos redujo la viabilidad celular de forma dosis dependiente, lo que fue contrarrestado por AQ e IP, los que fueron menos activos en las células inducibles por concanavalina A (p<0,05). La toxicidad por clorpirifos implicó la inducción de la ?-glutamiltranspeptidasa con la consecuente reducción de los peróxidos, mientras que AQ y principalmente IP antagonizaron dichas respuestas (p<0,05). Conclusiones: Los extractos de Ilex paraguariensis y Aspidosperma quebracho-blanco protegieron in vitro a los esplenocitos frente a clorpirifos. Este efecto dependió del tipo celular, dado que las células inducibles por concanavalina A fueron más susceptibles a este tóxico.

[Ag115S34(SCH2C6H4 tBu)47(dpph)6]: synthesis, crystal structure and NMR investigations of a soluble silver chalcogenide nanocluster† †Dedicated to Evamarie Hey-Hawkins on the occasion of her 60th birthday. ‡ ‡Electronic supplementary information (ESI) available: CCDC 1507868. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c6sc04578b Click here for additional data file. Click here for additional data file.

PubMed Central

Fuhr, Olaf; Breitung, Ben; Kiran Chakravadhanula, Venkata Sei; Guthausen, Gisela; Hennrich, Frank; Yu, Wen; Kappes, Manfred M.; Roesky, Peter W.

2017-01-01

With the aim to synthesize soluble cluster molecules, the silver salt of (4-(tert-butyl)phenyl)methanethiol [AgSCH2C6H4 tBu] was applied as a suitable precursor for the formation of a nanoscale silver sulfide cluster. In the presence of 1,6-(diphenylphosphino)hexane (dpph), the 115 nuclear silver cluster [Ag115S34(SCH2C6H4 tBu)47(dpph)6] was obtained. The molecular structure of this compound was elucidated by single crystal X-ray analysis and fully characterized by spectroscopic techniques. In contrast to most of the previously published cluster compounds with more than a hundred heavy atoms, this nanoscale inorganic molecule is soluble in organic solvents, which allowed a comprehensive investigation in solution by UV-Vis spectroscopy and one- and two-dimensional NMR spectroscopy including 31P/109Ag-HSQC and DOSY experiments. These are the first heteronuclear NMR investigations on coinage metal chalcogenides. They give some first insight into the behavior of nanoscale silver sulfide clusters in solution. Additionally, molecular weight determinations were performed by 2D analytical ultracentrifugation and HR-TEM investigations confirm the presence of size-homogeneous nanoparticles present in solution. PMID:28507679

Synergistic Anion-(π) n-π Catalysis on π-Stacked Foldamers.

PubMed

Bornhof, Anna-Bea; Bauzá, Antonio; Aster, Alexander; Pupier, Marion; Frontera, Antonio; Vauthey, Eric; Sakai, Naomi; Matile, Stefan

2018-04-11

In this report, we demonstrate that synergistic effects between π-π stacking and anion-π interactions in π-stacked foldamers provide access to unprecedented catalytic activity. To elaborate on anion-(π) n -π catalysis, we have designed, synthesized and evaluated a series of novel covalent oligomers with up to four face-to-face stacked naphthalenediimides (NDIs). NMR analysis including DOSY confirms folding into π stacks, cyclic voltammetry, steady-state and transient absorption spectroscopy the electronic communication within the π stacks. Catalytic activity, assessed by chemoselective catalysis of the intrinsically disfavored but biologically relevant addition reaction of malonate half thioesters to enolate acceptors, increases linearly with the length of the stacks to reach values that are otherwise beyond reach. This linear increase violates the sublinear power laws of oligomer chemistry. The comparison of catalytic activity with ratiometric changes in absorption and decreasing energy of the LUMO thus results in superlinearity, that is synergistic amplification of anion-π catalysis by remote control over the entire stack. In computational models, increasing length of the π-stacked foldamers correlates sublinearly with changes in surface potentials, chloride binding energies, and the distances between chloride and π surface and within the π stack. Computational evidence is presented that the selective acceleration of disfavored but relevant enolate chemistry by anion-π catalysis indeed originates from the discrimination of planar and bent tautomers with delocalized and localized charges, respectively, on π-acidic surfaces. Computed binding energies of keto and enol intermediates of the addition reaction as well as their difference increase with increasing length of the π stack and thus reflect experimental trends correctly. These results demonstrate that anion-(π) n -π interactions exist and matter, ready for use as a unique new tool in catalysis and beyond.

Sterile insect technique: A model for dose optimisation for improved sterile insect quality

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

Parker, A.; Mehta, K.

The sterile insect technique (SIT) is an environment-friendly pest control technique with application in the area-wide integrated control of key pests, including the suppression or elimination of introduced populations and the exclusion of new introductions. Reproductive sterility is normally induced by ionizing radiation, a convenient and consistent method that maintains a reasonable degree of competitiveness in the released insects. The cost and effectiveness of a control program integrating the SIT depend on the balance between sterility and competitiveness, but it appears that current operational programs with an SIT component are not achieving an appropriate balance. In this paper we discussmore » optimization of the sterilization process and present a simple model and procedure for determining the optimum dose. (author) [Spanish] La tecnica de insecto esteril (TIE) es una tecnologia de control de plagas favorable para el medio ambiente con una aplicacion de un control integrado de plagas claves para toda la area, incluyendo la supresion o eliminacion de poblaciones introducidas y la exclusion de nuevas introducciones. La esterilidad reproductiva es normalmente inducida por radiacion ionizada, un metodo conveniente y consistente que mantiene un grado razonable para la capacidad de competencia en insectos liberados. El costo y la eficacia de un programa de control que incluye TIE dependen en tener un balance entre la esterilidad y la capacidad para competir, pero parece que los programas operacionales corrientes con TIS como un componente no estan logrando el tener un balance apropiado. En esta publicacion, nosotros discutimos la optimizacion del proceso de esterilizacion y presentamos un modelo y procedimiento sencillos para determinar la dosis optima. (author)« less

Tyramine functions as a toxin in honey bee larvae during Varroa-transmitted infection by Melissococcus pluton.

PubMed

Kanbar, G; Engels, W; Nicholson, G J; Hertle, R; Winkelmann, G

2004-05-01

From wounds of honey bee pupae, caused by the mite Varroa destructor, coccoid bacteria were isolated and identified as Melissococcus pluton. The bacterial isolate was grown anaerobically in sorbitol medium to produce a toxic compound that was purified on XAD columns, gelfiltration and preparative HPLC. The toxic agent was identified by GC-MS and FTICR-MS as tyramine. The toxicity of the isolated tyramine was tested by a novel mobility test using the protozoon Stylonychia lemnae. A concentration of 0.2 mg/ml led to immediate inhibition of mobility. In addition the toxicity was studied on honey bee larvae by feeding tyramine/water mixtures added to the larval jelly. The lethal dosis of tyramine on 4-5 days old bee larvae was determined as 0.3 mg/larvae when added as a volume of 20 microl to the larval food in brood cells. Several other biogenic amines, such as phenylethylamine, histamine, spermine, cadaverine, putrescine and trimethylamine, were tested as their hydrochloric salts for comparison and were found to be inhibitory in the Stylonychia mobility test at similar concentrations. A quantitative hemolysis test with human red blood cells revealed that tyramine and histamine showed the highest membranolytic activity, followed by the phenylethylamine, trimethylamine and spermine, while the linear diamines, cadaverine and putrescine, showed a significantly lower hemolysis when calculated on a molar amine basis. The results indicate that tyramine which is a characteristic amine produced by M. pluton in culture, is the causative agent of the observed toxic symptoms in bee larvae. Thus this disease, known as European foulbrood, is possibly an infection transmitted by the Varroa destructor mite.

Fundamental Characterization of the Micellar Self-Assembly of Sophorolipid Esters.

PubMed

Koh, Amanda; Todd, Katherine; Sherbourne, Ezekiel; Gross, Richard A

2017-06-13

Surfactants are ubiquitous constituents of commercial and biological systems that function based on complex structure-dependent interactions. Sophorolipid (SL) n-alkyl esters (SL-esters) comprise a group of modified naturally derived glycolipids from Candida bombicola. Herein, micellar self-assembly behavior as a function of SL-ester chain length was studied. Surface tensions as low as 31.2 mN/m and critical micelle concentrations (CMCs) as low as 1.1 μM were attained for diacetylated SL-decyl ester (dASL-DE) and SL-octyl ester, respectively. For deacetylated SL-esters, CMC values reach a lower limit at SL-ester chains above n-butyl (SL-BE, 1-3 μM). This behavior of SL-esters with increasing hydrophobic tail length is unlike other known surfactants. Diffusion-ordered spectroscopy (DOSY) and T 1 relaxation NMR experiments indicate this behavior is due to a change in intramolecular interactions, which impedes the self-assembly of SL-esters with chain lengths above SL-BE. This hypothesis is supported by micellar thermodynamics where a disruption in trends occurs at n-alkyl ester chain lengths above those of SL-BE and SL-hexyl ester (SL-HE). Diacetylated (dA) SL-esters exhibit an even more unusual trend in that CMC increases from 1.75 to 815 μM for SL-ester chain lengths of dASL-BE and dASL-DE, respectively. Foaming studies, performed to reveal the macroscopic implications of SL-ester micellar behavior, show that the observed instability in foams formed using SL-esters are due to coalescence, which highlights the importance of understanding intermicellar interactions. This work reveals that SL-esters are an important new family of green high-performing surfactants with unique structure-property relationships that can be tuned to optimize micellar characteristics.

[Botulinum toxin: from poison to drug. A historical review].

PubMed

Kreyden, O P; Geiges, M L; Böni, R; Burg, G

2000-10-01

Botulinumtoxin (BTX) is a neurotoxin produced from Clostridium botulinum under anaerobic conditions and is responsible for botulism, a notifiable, bacterial form of food poisoning. The first case of botulism is believed to have occurred in 1735. An epidemic in Southern Germany in 1793 claimed the death of over the half of those patients who had become ill through eating uncooked blood sausages. The term "pharmakon" is Greek and implicates that a drug originates from poison (potion, remedy). Theophrastus Bombast von Hohenheim known as Paracelsus (1493/94-1541) first described this duality with his dictum "alle ding sind gift und nichts on gift; alein die dosis macht das ein ding kein gift ist" (only the dose makes a remedy poisonous). In Baden-Württemberg in 1817, the poet and physician Dr. Justinus Christian Kerner described the symptoms of botulism, so that at this time botulism was also called Kerner disease. Until the turn of the century the reason for poisoning was not known. Van Ermengem succeeded in isolating the anaerobic bacterium causing botulism, but the specific mechanism of BTX was only established after the second World War. In the late seventies the ophthalmologist Dr. Alan Scott used BTX the first time in the treatment of strabismus. The drug was then used in the treatment of several muscle spasticities such as, for example, torticollis or hemifacial spasm. Only recently BTX has been successfully used for focal hyperhidrosis. We review the history of botulinum toxin from its discovery in the nineteenth century and the research into its effect in the middle of the 20th century up to its clinical use at the present time.

Two Compartmentalized Inner Receptors for the Tetramethylammonium Guest within a Keplerate-Type Capsule.

PubMed

Watfa, Nancy; Haouas, Mohamed; Floquet, Sébastien; Hijazi, Akram; Naoufal, Daoud; Taulelle, Francis; Cadot, Emmanuel

2016-09-19

The host-guest interactions between the spherical porous Keplerate anion, [Mo132O372(CH3CO2)30(H2O)72](42-) (abbreviated {Mo132}) and the tetramethylammonium cation have been investigated extensively by one- and two-dimensional (EXSY, ROESY, and DOSY) and variable-temperature NMR. Evidence of two inner receptor sites specific for a NMe4(+) guest appears consistent with a quite striking compartmentalization phenomenon. ROESY NMR analyses showed that both sites exhibit a close spatial proximity with the hanging inner acetate groups, while a quantitative EXSY study revealed that these two sites are differentiated by their exchange rates. These NMR data support the hypothesis that these two inner sites could be delimited by the hanging inner acetate groups forming triangular (S1) or pentagonal (S2) hydrophobic pockets on the inner side of the capsule wall. Furthermore, the stability constants associated with the trapping process of the NMe4(+) guest on both the S1 and S2 sites have been determined, showing that the stability constant of the S1 sites decreases significantly as the concentration of the capsule increases gradually, while that of the S2 sites remains nearly unaffected. Such an observation has been interpreted as a result of the plugging process of the {Mo9O9} pores by the counterions NH4(+), which causes unfavorable electrostatic interactions for the NMe4(+) coordination on the proximal S1 site. Finally, the thermodynamic parameters of the NMe4(+) transfer from the solvated situation to the interior of the capsule were estimated from variable-temperature NMR experiments that provide the split of the global process into two successive events corresponding to the plugging and transfer across the inorganic shell.

A remarkable solvent effect on the nuclearity of neutral titanium(IV)-based helicate assemblies.

PubMed

Weekes, David Michael; Diebold, Carine; Mobian, Pierre; Huguenard, Clarisse; Allouche, Lionel; Henry, Marc

2014-04-22

The spontaneous self-assembly of a neutral circular trinuclear Ti(IV) -based helicate is described through the reaction of titanium(IV) isopropoxide with a rationally designed tetraphenolic ligand. The trimeric ring helicate was obtained after diffusion of n-pentane into a solution with dichloromethane. The circular helicate has been characterized by using single-crystal X-ray diffraction study, (13) C CP-MAS NMR and (1) H NMR DOSY solution spectroscopic, and positive electrospray ionization mass-spectrometric analysis. These analytical data were compared with those obtained from a previously reported double-stranded helicate that crystallizes in toluene. The trimeric ring was unstable in a pure solution with dichloromethane and transformed into the double-stranded helicate. Thermodynamic analysis by means of the PACHA software revealed that formation of the double-stranded helicates was characterized by ΔH(toluene)=-30 kJ mol(-1) and ΔS(toluene)=+357 J K(-1)  mol(-1) , whereas these values were ΔH(CH2 Cl2 )=-75 kJ mol(-1) and ΔS(CH2 Cl2 )=-37 J K(-1)  mol(-1) for the ring helicate. The transformation of the ring helicate into the double-stranded helicate was a strongly endothermic process characterized by ΔH(CH2 Cl2 )=+127 kJ mol(-1) and ΔH(n-pentane)=+644 kJ mol(-1) associated with a large positive entropy change ΔS=+1115 J K(-1) ⋅mol(-1) . Consequently, the instability of the ring helicate in pure dichloromethane was attributed to the rather high dielectric constant and dipole moment of dichloromethane relative to n-pentane. Suggestions for increasing the stability of the ring helicate are given. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

PubMed

Valero Chávez, Francisco Javier; Luengo Pérez, Luis Miguel; Cubero Juánez, Javier

2016-09-20

Introducción: ante las nuevas implicaciones atribuidas a la vitamina D y la asociación con enfermedades tales como el cáncer, diabetes, enfermedades cardiovasculares, autoinmunes y mortalidad, no es de extrañar que se haya defendido la medición de los niveles de vitamina D en la población general. Sin embargo, no existen datos experimentales que demuestren la viabilidad y rentabilidad de la estrategia de cribado en la población y tampoco se ha comprobado la existencia de beneficios para la salud, por lo que en la actualidad solo es aconsejable la medida de 25 (OH) vitamina D en los grupos de personas de alto riesgo como indican las guías clínicas internacionales.Objetivos: analizar las peticiones de vitamina D comprobando si se adecuan a las guías clínicas.Métodos: realizamos un estudio descriptivo transversal en el Área de Salud de Badajoz (España) estudiando las peticiones de determinación de vitamina D durante 12 meses consecutivos (n = 3.907). En dicho estudio revisamos el diagnóstico de petición y la historia clínica del paciente para discriminar entre peticiones que se adecuaban a las guías clínicas y peticiones injustificadas. Por último, realizamos el estudio económico.Resultados: en nuestros resultados encontramos que casi un tercio de peticiones no se adecuaban a las guías clínicas, en patologías tales como diabetes, dislipemias e hipertensión en las que no está recomendada la medición de los niveles de vitamina D, por lo que suponía un exceso de gasto para el sistema sanitario. Gasto que se incrementa cada año, tanto es así que se ha producido un aumento en las peticiones de más del 1.000% en los últimos 6 años.Conclusiones: concluimos la necesidad de crear protocolos de petición de vitamina D que se ajusten a las guías clínicas hasta que existan más estudios experimentales sobre las nuevas implicaciones de la vitamina D y así conseguir una correcta utilización de los recursos económicos del hospital.

Estimaciones de Prevalencia del VIH por Género y Grupo de Riesgo en Tijuana, México: 2006

PubMed Central

Iñiguez-Stevens, Esmeralda; Brouwer, Kimberly C.; Hogg, Robert S.; Patterson, Thomas L.; Lozada, Remedios; Magis-Rodriguez, Carlos; Elder, John P.; Viani, Rolando M.; Strathdee, Steffanie A.

2010-01-01

OBJETIVO Estimar la prevalencia del VIH en adultos de 15-49 años de edad en Tijuana, México - en la población general y en subgrupos de riesgo en el 2006. METODOS Se obtuvieron datos demográficos del censo Mexicano del 2005, y la prevalencia del VIH se obtuvo de la literatura. Se construyó un modelo de prevalencia del VIH para la población general y de acuerdo al género. El análisis de sensibilidad consistió en estimar errores estándar del promedio-ponderado de la prevalencia del VIH y tomar derivados parciales con respecto a cada parámetro. RESULTADOS La prevalencia del VIH es 0.54%(N = 4,347) (Rango: 0.22%–0.86%, (N = 1,750–6,944)). Esto sugiere que 0.85%(Rango: 0.39%–1.31%) de los hombres y 0.22%(Rango: 0.04%–0.40%) de las mujeres podrían ser VIH-positivos. Los hombres que tienen sexo con hombres (HSH), las trabajadoras sexuales usuarias de drogas inyectables (MTS-UDI), MTS-noUDI, mujeres UDI, y los hombres UDI contribuyeron las proporciones más elevadas de personas infectadas por el VIH. CONCLUSIONES El número de adultos VIH-positivos entre subgrupos de riesgo en la población de Tijuana es considerable, marcando la necesidad de enforcar las intervenciones de prevención en sus necesidades específicas. El presente modelo estima que hasta 1 en cada 116 adultos podrían ser VIH-positivos. PMID:19685824

Preparation and Current Situation of Proton-ICCHIBAN-2 Experiment

NASA Astrophysics Data System (ADS)

Uchihori, Yukio; Yasuda, Nakahiro; Kitamura, H.; Kodaira, S.; Benton, Eric; Hajek, Michael; Berger, Thomas; Jadrnickova, Iva; Ploc, Ondrej

The ICCHIBAN (Inter Comparison for Cosmicrays with Heavy Ion Beams at NIRS) working group has organized and performed various ICCHIBAN runs for active and passive radiation detectors at HIMAC, NIRS, Japan, Loma Linda and Brookhaven, USA and CERN, Switzer-land since the start of the ICCHIBAN project in the year 2002. One of the main focus points of this project is to understand the response of the applied detector systems (either active or passive) for personal and area dosimetry in space environment to a simulated sub-set of the space radiation environment, focusing on the heavy ion response. This is of special importance for the further intercomparison of space radiation data gathered by various international in-stitutes and universities for space radiation experiments as MATROSHKA, DOSIS, DOBIES, BRADOS, MATROSHKA-R etc. The ICCHIBAN experiments have created a big database of response data, especially for all the different passive radiation detectors and detector materials (Thermoluminescence (TLD) and Optical Luminescence (OSL)) over the last 7 years, resulting in a better understanding of how and why we still have differences in the measurement results from common space experiments -as the Space ICCHIBAN 2 experiment. One of the reasons why for the differences in the TLD/OSL results is the lack of intercomparison and response data for low LET particles up to around 10 keV/m, especially protons. Due to the fact, that the main contribution to absorbed dose in low earth orbit is due to protons, the ICCHIBAN working group has started the set-up of a Proton ICCHIBAN intercomparison experiment at NIRS. The Proton ICCHIBAN run has been performed at the cyclotron at NIRS, Chiba in February 2010. 15 institutes from 12 countries sent or brought their dosimeters and exposed them to 40 and 70 MeV proton beams with the same doses and exposure conditions. In this paper, the experiment procedures and current situation of the intercomparision experiments will be shown.

Diode laser for endodontic treatment: investigations of light distribution and disinfection efficiency

NASA Astrophysics Data System (ADS)

Stock, Karl; Graser, Rainer; Udart, Martin; Kienle, Alwin; Hibst, Raimund

2011-03-01

Diode lasers are used in dentistry mainly for oral surgery and disinfection of root canals in endodontic treatment. The purpose of this study was to investigate and to improve the laser induced bacteria inactivation in endodontic treatment. An essential prerequisite of the optimization of the irradiation process and device is the knowledge about the determinative factors of bacteria killing: light intensity? light dosis? temperature? In order to find out whether high power NIR laser bacterial killing is caused by a photochemical or a photothermal process we heated bacteria suspensions of E. coli K12 by a water bath and by a diode laser (940 nm) with the same temporal temperature course. Furthermore, bacteria suspensions were irradiated while the temperature was fixed by ice water. Killing of bacteria was measured via fluorescence labeling. In order to optimize the irradiation of the root canal, we designed special fiber tips with radial light emission characteristic by optical ray tracing simulations. Also, we calculated the resulting light distribution in dentin by voxelbased Monte Carlo simulations. Furthermore, we irradiated root canals of extracted human teeth using different fiber tip geometries and measured the resulting light and heat distribution by CCD-camera and thermography. Comparison of killing rates between laser and water based heating shows no significant differences, and irradiation of ice cooled suspensions has no substantial killing effect. Thus, the most important parameter for bacterial killing is the maximum temperature. Irradiation of root canals using fiber tips with radial light emission results in a more defined irradiated area with minor irradiation of the apex and higher intensity and therefore higher temperature increase on root canal surface. In conclusion, our experiments show that at least for E. coli bacteria inactivation by NIR laser irradiation is solely based on a thermal process and that heat distribution in root canal can be significantly improved by specially designed fiber tips.

Liquid-State NMR Analysis of Nanocelluloses.

PubMed

King, Alistair W T; Mäkelä, Valtteri; Kedzior, Stephanie A; Laaksonen, Tiina; Partl, Gabriel J; Heikkinen, Sami; Koskela, Harri; Heikkinen, Harri A; Holding, Ashley J; Cranston, Emily D; Kilpeläinen, Ilkka

2018-04-11

Recent developments in ionic liquid electrolytes for cellulose or biomass dissolution has also allowed for high-resolution 1 H and 13 C NMR on very high molecular weight cellulose. This permits the development of advanced liquid-state quantitative NMR methods for characterization of unsubstituted and low degree of substitution celluloses, for example, surface-modified nanocelluloses, which are insoluble in all molecular solvents. As such, we present the use of the tetrabutylphosphonium acetate ([P 4444 ][OAc]):DMSO- d 6 electrolyte in the 1D and 2D NMR characterization of poly(methyl methacrylate) (PMMA)-grafted cellulose nanocrystals (CNCs). PMMA- g-CNCs was chosen as a difficult model to study, to illustrate the potential of the technique. The chemical shift range of [P 4444 ][OAc] is completely upfield of the cellulose backbone signals, avoiding signal overlap. In addition, application of diffusion-editing for 1 H and HSQC was shown to be effective in the discrimination between PMMA polymer graft resonances and those from low molecular weight components arising from the solvent system. The bulk ratio of methyl methacrylate monomer to anhydroglucose unit was determined using a combination of HSQC and quantitative 13 C NMR. After detachment and recovery of the PMMA grafts, through methanolysis, DOSY NMR was used to determine the average self-diffusion coefficient and, hence, molecular weight of the grafts compared to self-diffusion coefficients for PMMA GPC standards. This finally led to a calculation of both graft length and graft density using liquid-state NMR techniques. In addition, it was possible to discriminate between triads and tetrads, associated with PMMA tacticity, of the PMMA still attached to the CNCs (before methanolysis). CNC reducing end and sulfate half ester resonances, from sulfuric acid hydrolysis, were also assignable. Furthermore, other biopolymers, such as hemicelluloses and proteins (silk and wool), were found to be soluble in the electrolyte media, allowing for wider application of this method beyond just cellulose analytics.

1,2,3-Triazole-Functionalized Polysulfone Synthesis through Microwave-Assisted Copper-Catalyzed Click Chemistry: A Highly Proton Conducting High Temperature Membrane.

PubMed

Sood, Rakhi; Donnadio, Anna; Giancola, Stefano; Kreisz, Aurélien; Jones, Deborah J; Cavaliere, Sara

2016-07-06

Microwave heating holds all the aces regarding development of effective and environmentally friendly methods to perform chemical transformations. Coupling the benefits of microwave-enhanced chemistry with highly reliable copper-catalyzed azide-alkyne cycloaddition (CuAAC) click chemistry paves the way for a rapid and efficient synthesis procedure to afford high performance thermoplastic materials. We describe herein fast and high yielding synthesis of 1,2,3-triazole-functionalized polysulfone through microwave-assisted CuAAC as well as explore their potential as phosphoric acid doped polymer electrolyte membranes (PEM) for high temperature PEM fuel cells. Polymers with various degrees of substitution of the side-chain functionality of 1,4-substituted 1,2,3-triazole with alkyl and aryl pendant structures are prepared by sequential chloromethylation, azidation, and microwave-assisted CuAAC using a range of alkynes (1-pentyne, 1-nonyne, and phenylacetylene). The completeness of reaction at each step and the purity of the clicked polymers were confirmed by (1)H-(13)C NMR, DOSY-NMR and FTIR-ATR spectroscopies. The thermal and thermochemical properties of the modified polymers were characterized by differential scanning calorimetry and thermogravimetric analysis coupled with mass spectroscopy (TG-MS), respectively. TG-MS analysis demonstrated that the commencement of the thermal degradation takes place with the decomposition of the triazole ring while its substituents have critical influence on the initiation temperature. Polysulfone functionalized with 4-phenyl-1,2,3-triazole demonstrates significantly higher Tg, Td, and elastic modulus than the ones bearing 4-propyl-1,2,3-triazole and 4-heptyl-1,2,3-triazole groups. After doping with phosphoric acid, the functionalized polymers with acid doping level of 5 show promising performance with high proton conductivity in anhydrous conditions (in the range of 27-35 mS/cm) and satisfactorily high elastic modulus (in the range of 332-349 MPa).

Comparison of longevity between a laboratory strain and a natural population of Anastrepha Fraterculus (Diptera: Tephritidae) under field cage conditions

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

Gomez Cendra, P.; Vilardi, J.; Segura, D.

The South American fruit fly Anastrepha fraterculus (Wiedemann) is one of the most destructive fruit pests in this region, infesting major fruit crops. Implementation of the sterile insect technique (SIT) as part of an area-wide integrated approach against this species requires information on the survival of mass-reared and sterilized insects in the field and their ability to mate with wild females. The survival rates in field cages of both non-irradiated and irradiated laboratory flies were compared with that of wild flies. Both types of laboratory flies survived longer than their wild counterparts over the 8 days under the experimental conditions.more » The irradiation dose (70 Gy) did not affect survival of the laboratory reared flies. Our results improve the prospect of integrating the SIT into the control of A. fraterculus populations in Argentina. (author) [Spanish] Anastrepha fraterculus (Wiedemann), la mosca sudamericana de la fruta, es una de las plagas mas destructivas en la region que infesta a los principales cultivos de frutas. La implementacion de la Tecnica del Insecto Esteril (TIE) como parte de un manejo integrado en areas extensivas contra esta especie requiere ensayos que demuestren que los insectos producidos en forma masiva y esterilizados son capaces de sobrevivir en el campo y aparearse con las hembras silvestres. Se comparo la supervivencia de individuos de una linea de laboratorio, tanto irradiados como no irradiados con la de individuos de una poblacion natural. Los dos tratamientos de moscas de laboratorio sobrevivieron mas tiempo que las salvajes durante los 8 dias y en las condiciones ensayadas. La dosis de radiacion (70 Gy.) no afecto la supervivencia de las moscas criadas en laboratorio. Nuestros resultados mejoran las perspectivas de integrar la TIE en el control de las poblaciones argentinas de A. fraterculus. (author)« less

Clinical Validation of the Nursing Outcome "Swallowing Status" in People with Stroke: Analysis According to the Classical and Item Response Theories.

PubMed

Oliveira-Kumakura, Ana Railka de Souza; de Araujo, Thelma Leite; Costa, Alice Gabrielle de Sousa; Cavalcante, Tahissa Frota; Lopes, Marcos Venícios de Oliveira; Carvalho, Emilia Campos

2017-09-19

To validate clinically the nursing outcome "Swallowing status". The adjustment of the nursing outcome was investigated according to the Classical and Item Response Theories. The models were compared regarding information loss, goodness-of-fit, and differential item functioning. Stability and internal consistency were examined. The nursing outcome has the best fit in the generalized partial credit model with different discrimination parameters. Strong correlations among the scores of each indicator were observed. There was no differential item functioning of the outcome indicators. The scale presented high internal consistency (Cronbach's α = .954) and stability (and > .800). This study presents a valid nursing outcome. Most accurate monitoring of sensitivity to an intervention. Validar clinicamente o resultado de enefermagem "Estado da Deglutição". MÉTODOS: O ajustamento do resultado foi investigado de acordo com as teorias Clássica e de Resposta ao Item. Os modelos foram comparados assumindo parâmetros de itens cruzados de igual discriminação. Investigaram-se as propriedades de bondade do ajuste, funcionamento diferencial dos itens, estabilidade e consistência interna. O resultado se ajustou melhor a partir do Modelo de crédito parcial generalizado, o qual demonstrou unidimensionalidade do resultado e forte correlação entre os escores de cada indicador. Não houve funcionamento diferencial dos indicadores. A consistência interna para a escala global (Cronbach's α = .954) e a estabilidade (>.800) mantiveram-se elevadas. CONCLUSÃO: O estudo apresenta um resultado de enfermagem válido. RELEVÂNCIA PARA A PRÁTICA CLÍNICA: Maior acurácia para monitorar a sensibilidade da intervenção. © 2017 NANDA International, Inc.

[In Process Citation].

PubMed

Blázquez, Ferrán Padrós; Navarro Contreras, Gabriela; Garcidueñas Gallegos, Diana; Fulgencio Juárez, Mónica

2016-03-25

Introducción: la obesidad es una enfermedad asociada a diferentes trastornos físicos y emocionales que inciden en la calidad de vida y que representan un problema de elevada prevalencia en el mundo. La etiología es múltiple y compleja; se ha señalado la culpa como consecuencia del sobrepeso y, al mismo tiempo, como factor asociado al aumento de peso. En México no existen instrumentos para evaluar la culpa por obesidad y sobrepeso en niños y adolescentes. Objetivos: analizar la fiabilidad y validez de la Escala de Culpa por Obesidad o Sobrepeso para Niños y Adolescentes (ECOSNA) en población de Morelia (México). Material y métodos: se elaboró una versión preliminar basada en la bibliografía que se sometió a la revisión de jueces expertos. La escala obtenida de 6 ítems se aplicó a una muestra de 1.418 estudiantes de educación básica de 7 a 15 años. Se realizó un análisis factorial confir- matorio y se estudió la relación de la escala con otras variables como autoestima, sintomatología depresiva y ansiedad. Resultados: la escala resultó unifactorial, se obtuvo un índice alfa de Cronbach de 0,853. La escala ECOSNA mostró una correlación moderada e inversa con la escala de autoestima, y directa y baja con la sintomatología depresiva y la ansiedad clínica. Conclusión: los datos empíricos indican que la escala presenta una validez y confiabilidad satisfactorias.

TENDENCIA DE LA TUBERCULOSIS EN LA REGIÓN SANITARIA V DE LA PROVINCIA DE BUENOS AIRES, AÑOS 2000–2011

PubMed Central

CHIRICO, CRISTINA; SANJURJO, MYRIAM; IRIBARREN, SARAH; APPENDINO, ANDREA; ZERBINI, ELSA; ETCHEVARRIA, MIRTA

2016-01-01

El objetivo del presente trabajo fue analizar la situación epidemiológica de la tuberculosis (TB) en la Región Sanitaria V (RSV), provincia de Buenos Aires. El estudio de tendencia permitió conocer un valor promedio de las variaciones de la tasa de incidencia (TI), calculadas por regresión lineal simple y expresadas como variación anual promedio (VAP). Se analizaron el número de casos notificados y TI por 100 000 habitantes de todas las formas de TB, los casos de TB pulmonar (TBP) y TBP confirmados por bacteriología, total casos por grupos de edad: 0 – 14; 15 – 29 y mayores de 64 años, entre el 1° de enero de 2000 al 31 de diciembre de 2011. La declinación de la TI fue menor al 5% para todas las formas de TB e inferior en las TBP confirmadas bacteriológicamente. Los casos de TBP y TI más elevadas, se concentraron en el grupo de 15 a 29 años, con tendencia estable o ligeramente ascendente de la TI en la TBP bacilífera. El mismo comportamiento presentaron los casos de TBP infantil con confirmación bacteriológica. La mayor velocidad de descenso en la TI de la TBP se produjo en este grupo de edad, mientras que en mayores de 64 años, el descenso fue sostenido en el tiempo. La TB persiste como un riesgo de salud en la RSV, con casos en edades jóvenes, por lo que sigue siendo necesario fortalecer el control de la TB en esta región. PMID:26117604

Recent transmission of drug-resistant Mycobacterium tuberculosis in a prison population in southern Brazil.

PubMed

Reis, Ana Julia; David, Simone Maria Martini de; Nunes, Luciana de Souza; Valim, Andreia Rosane de Moura; Possuelo, Lia Gonçalves

2016-01-01

We conducted a cross-sectional, retrospective study, characterized by classical and molecular epidemiology, involving M. tuberculosis isolates from a regional prison in southern Brazil. Between January of 2011 and August of 2014, 379 prisoners underwent sputum smear microscopy and culture; 53 (13.9%) were diagnosed with active tuberculosis. Of those, 8 (22.9%) presented with isoniazid-resistant tuberculosis. Strain genotyping was carried out by 15-locus mycobacterial interspersed repetitive unit-variable-number tandem-repeat analysis; 68.6% of the patients were distributed into five clusters, and 87.5% of the resistant cases were in the same cluster. The frequency of drug-resistant tuberculosis cases and the rate of recent transmission were high. Our data suggest the need to implement an effective tuberculosis control program within the prison system. RESUMO Estudo transversal, retrospectivo, com isolados de M. tuberculosis de pacientes de um presídio regional no sul do Brasil, caracterizado através de epidemiologia clássica e molecular. Entre janeiro de 2011 e agosto de 2014, 379 detentos foram submetidos a baciloscopia e cultura, sendo 53 (13,9%) diagnosticados com tuberculose ativa. Desses, 8 (22,9%) apresentavam tuberculose resistente a isoniazida. A genotipagem das cepas foi realizada por 15-locus mycobacterial interspersed repetitive units-variable number of tandem repeat analysis; 68,6% dos pacientes estavam distribuídos em cinco clusters, e 87,5% dos casos resistentes estavam em um mesmo cluster. Verificou-se uma frequência elevada de casos de resistência e alta taxa de transmissão recente. Estes dados sugerem a necessidade da implantação de um programa efetivo de controle da tuberculose no sistema prisional.

Adherence to immunosuppressive therapy following liver transplantation: an integrative review.

PubMed

Oliveira, Ramon Antônio; Turrini, Ruth Natália Teresa; Poveda, Vanessa de Brito

2016-08-29

to investigate the evidence available in the literature on non-adherence to immunosuppressive therapy among patients undergoing liver transplantation. integrative literature review, including research whose sample consisted of patients aged over 18 years undergoing liver transplantation. It excluded those containing patients undergoing multiple organ transplants. For the selection of articles, Medline / Pubmed, CINAHL, LILACS, Scopus and Embase were searched. The search period corresponded to the initial date of indexation of different bases, up to the deadline of February 10, 2015, using controlled and uncontrolled descriptors: liver transplantation, hepatic transplantation, liver orthotopic transplantation, medication adherence, medication non-adherence, medication compliance and patient compliance. were located 191 investigations, 10 of which met the objectives of the study and were grouped into four categories, namely: educational process and non-adherence; non-adherence related to the number of daily doses of immunosuppressive medications; detection methods for non-adherence and side effects of therapy. there were risk factors related to the health service, such as control and reduction of the number of doses; related to the individual, such as being male, divorced, alcohol or other substances user, exposed to low social support and being mentally ill. investigar as evidências disponíveis na literatura sobre a não adesão à terapêutica imunossupressora entre pacientes submetidos ao transplante de fígado. revisão integrativa da literatura, que incluiu investigações cuja amostra era composta por pacientes com idade igual ou superior a 18 anos, submetidos a transplante de fígado. Excluíram-se as que continham pacientes submetidos a transplantes de múltiplos órgãos. Para a seleção dos artigos foram consultadas as bases Medline/Pubmed, CINAHL, LILACS, Scopus e Embase. O período de busca determinado correspondeu à data inicial de indexação das diferentes bases, até a data limite de 10 de fevereiro de 2015, empregando-se os descritores controlados e não controlados: liver transplantation, hepatic transplantation, liver orthotopic transplantation, medication adherence, medication non-adherence, medication compliance e patient compliance. foram localizadas 191 investigações, das quais 10 atenderam aos objetivos do estudo e foram agrupadas em quatro categorias, a saber: processo educativo e ocorrência de não adesão; não adesão relacionada ao número de doses diárias dos medicamentos imunossupressores; métodos de detecção da não adesão e efeitos colaterais da terapêutica. verificou-se a existência de fatores de risco relacionados ao serviço de saúde, como controle e redução do número de doses; relacionados ao indivíduo, como ser do sexo masculino, divorciado, usuário de álcool ou outras substâncias, expostos a menor suporte social e portadores de transtorno mental. investigar la evidencia disponible en la literatura sobre la falta de adherencia a la terapia inmunosupresora en los pacientes sometidos a trasplante hepático. revisión integradora de la literatura, que incluye investigaciones cuya muestra estaba constituida por pacientes mayores de 18 años sometidos a trasplante hepático. Se excluyeron aquellos que tenían pacientes sometidos a trasplantes de varios órganos. Para la selección de los artículos fueron consultadas las bases Medline / Pubmed, CINAHL, LILACS, Scopus y Embase. El período de búsqueda determinado correspondió a la fecha inicial de indexación de las diferentes bases, con fecha límite de 10 de febrero de 2015, usándose descriptores controlados y no controlados: liver transplantation, hepatic transplantation, liver orthotopic transplantation, medication adherence, medication non-adherence, medication compliance e patient compliance. se localizaron 191 investigaciones, de los cuales 10 cumplieron con los objetivos del estudio y se agruparon en cuatro categorías, a saber: proceso educativo y ocurrencia de no adhesión; falta de adhesión relacionada con el número de dosis diarias de medicamentos inmunosupresores; métodos de detección de la falta de adhesión y los efectos secundarios de la terapia. se verificaron factores de riesgo relacionados con el servicio de salud, tales como el control y la reducción del número de dosis; inherentes a la persona, como ser hombre, divorciado, usuario de alcohol u otras sustancias, expuestos a un menor apoyo social y portadores de enfermedades mentales.

Mercaptursäure und Nukleosidaddukt im Harn als Biomarker in 1-Hydroxymethylpyren-exponierten Ratten

NASA Astrophysics Data System (ADS)

Ma, Lan

2002-01-01

1-Methylpyren (MP) ist hepatokanzerogen in neugeborenen männlichen Mäusen. Durch Hydroxylierung an der benzylischen Stelle und anschließende Sulfonierung wird MP zu DNA-reaktivem 1-Sulfooxymethylpyren (SMP) aktiviert. In der Ratte führt die Exposition des benzylischen Alkohols, 1-Hydroxymethylpyren (HMP), zur DNA-Adduktbildung in verschiedenen Geweben. Eventuelle Konsequenz der Toxifizierung ist die Ausscheidung entsprechender Mercaptursäure und Nukleosidaddukt im Harn, welche aufgrund ihrer Herkunft als Biomarker eignen könnten. In dieser Arbeit wird die Ausscheidung der Mercaptursäure und des N2-Desoxyguanosinadduktes in HMP-exponierten Ratten untersucht. Nach der Applikation von HMP bzw. MP wurden weniger als 1 % der Dosis als MPMA über Urin und Faeces ausgeschieden (0 - 48 h). Die Ausscheidung erfolgt hauptsächlich in den ersten 24 h nach der Applikation. MPdG konnte weder in Urin noch in Faeces der HMP-behandelten Tieren identifiziert werden. Nach direkter SMP-Applikation wurde MPdG nur in sehr geringe Menge (weniger als 0,9 ppm in 12 h) im Urin gefunden. Aufgrund der geringen Menge eignet sich MPdG nicht als Biomarker. MPMA dagegen, lässt sich analytisch gut erfassen. Es sollte daher untersucht werden, ob MPMA die Toxifizierung des HMP wiederspiegelt. Die Voraussetzung dafür ist die Kenntnisse über das Metabolismusmuster von HMP. Es wurde daher umfassende Untersuchungen zum Metabolismus des HMP durchgeführt. Die Ergebnisse zeigten, dass mehr als 80 % der Metaboiten in ihrer oxidierten Form (PCS, deren Glucuronsäure-Konjugate sowie phenolische Sulfatester der PCS) ausgeschieden wurden. Demnach spielt die Oxidation des HMP zu PCS eine sehr wichtige Rolle bei der Detoxifizierung und Ausscheidung von HMP. Ferne konnte nachgewiesen werden, dass die Enzyme Alkohol- und Aldehyd-Dehydrogenase an der Oxidation von HMP beteiligt waren. Die Inhibitoren Disulfiram und Ethanol der o. g. Enzyme wurde daher zur Modulation der Detoxifizierung in vivo eingesetzt. Die Veränderungen in der Toxifizierung von HMP zu SMP wurden durch die SMP-Konzentration im Plasma, die DNA-Addukthäufigkeit und die MPMA-Ausscheidung erfasst. Die Vorbehandlung von Disulfiram und Ethanol führte zu tendentielle Erhöhung der SMP-Konzentration im Plasma, DNA-Addukthäufigkeit in der Leber und die MPMA-Ausscheidung. Bemerkenswert ist jedoch, dass bereits eine Dosis von 0,2 g Ethanol/kg Körpermasse bereits zu statistisch signifikanten Erhöhungen der MPMA-Ausscheidung bei weiblichen Ratten. 1-Methylpyrene is hepatocarcinogenic in rodents. It is metabolized primarily to 1-hydroxymethylpyrene (HMP) by various cDNA-expressed rat and human cytochromes P450. HMP is activated to a highly reactive sulfuric acid ester, 1-sulfooxymethylpyrene (SMP), by sulphotransferases. In the rat, this activation pathway leads to the formation of DNA adducts in various tissues. Possible consequences of the toxification could be the excretion of the corresponding mercapturic acid and nucleosidadduct in urine and feces. Because of their origin, these substances should reflex the toxification process may be used as biomarkers. We investigate the excretion of 1-methylpyrenyl-mercapturic acid (MPMA) and the excretion of N2-(1-methylpyrenyl)-desoxyguanosin (MPdG) in urine and feces of HMP-treated rats. These studies showed that only a minor portion (< 1 %) of the administered dose of 1-HMP was excreted as mercapturic acid. MPdG could not be identified in urine and feces of HMP-treated rats. Treating rats with the active spieces sulfooxymethylpyrene, 0.9 ppm of the dose was found excreted within 12 h. I now investigated the alternative metabolic pathways of HMP. More than 50 % of the dose (administered intraperitoneally) was excreted as free 1-pyrenyl carboxylic acid and its glucuronic acid conjugate primarily in the urine. Other major urinary metabolites were phenolic sulpho conjugates of ring-oxidized 1-pyrenyl carboxylic acid (> 30 %). Minor metabolites were phenolic sulpho conjugates of HMP (< 5 %). The glucuronic acid conjugate of HMP was found in very small amounts. In total, > 80 % of the metabolites excreted were oxidized at the exocyclic carbon. This side-chain oxidation, probably catalyzed by alcohol and aldehyde dehydrogenases, appears to represent a detoxification pathway. Indeed, administration of ethanol shortly before the administration of HMP to rats increased the levels of SMP detected in blood, of DNA adducts formed in tissues and of mercapturic acid excreted. These effects were observed even at very low dose levels of ethanol (0.2 g per kg body weight). Similar effects were shown after administration of Disulfiram, an inhibitor of aldehyde dehydrogenase.

Trastornos mentales y consumo de drogas en la población víctima del conflicto armado en tres ciudades de Colombia.

PubMed

Castaño, Guillermo; Sierra, Gloria; Sánchez, Daniela; Torres, Yolanda; Salas, Carolina; Buitrago, Carolina

2018-05-01

Introducción. La violencia en sus diferentes modalidades incrementa el riesgo de trastornos mentales y de consumo de drogas.Objetivos. Estimar la prevalencia de los trastornos mentales, del uso y abuso de drogas, así como los factores asociados en víctimas de desplazamiento forzado en tres ciudades colombianas.Materiales y métodos. Se hizo un estudio de prevalencia en una muestra de 1.026 personas entre los 13 y los 65 años de edad, a quienes se entrevistó utilizando el instrumento Composite International Diagnostic Interview y el Alcohol Use Disorders Identification Test de la Organización Mundial de la Salud, así como un cuestionario sobre el consumo de drogas modificado a partir de la encuesta del Sistema Interamericano de Datos Uniformes sobre Drogas de la Comisión Interamericana para el Control del Abuso de Drogas de la Organización de Estados Americanos, y otro sobre aspectos relacionados con el desplazamiento forzado. El análisis se hizo mediante el programa estadístico SPSS™, versión 21.Resultados. La prevalencia de vida de los trastornos mentales fue la siguiente: fobia específica, 17,7 %; depresión mayor, 16,4 %; estrés postraumático, 9,9 %; trastorno oposicionista desafiante, 8,9 %; ansiedad por separación, 7,2 %; trastornos de conducta, 5,8 %, y déficit de atención, 5,6 %. La prevalencia de vida del consumo de alcohol fue de 68,7 %; de tabaco, 31,3 %, de marihuana, 11,2 %, de cocaína, 3,5 %, de basuco, 2,0 %, de inhalables, 2,3 %, y de medicamentos ansiolíticos sin receta, 2,5 %, en tanto que 0,7 % de los entrevistados se había inyectado drogas. El presentar cualquiera de los trastornos mentales se asoció con el sexo femenino (odds ratio, OR=1,61; IC95% 1,21-2,14), así como el haber sido sometido a más de un desplazamiento forzado (OR=1,47; IC95 1,05-2,05). El consumo de cualquiera de las drogas se asoció con ser hombre (OR=5,38; IC95% 2,35-12,34).Conclusiones. La alta prevalencia de trastornos mentales y de consumo de drogas en la población estudiada, comparada con la población general, constituye un problema de salud pública que justifica el diseño de planes y la implementación de programas orientados a la recuperación de su bienestar y salud mental.

Prevalence of hypoalbuminemia and nutritional issues in hospitalized elders.

PubMed

Brock, Felipe; Bettinelli, Luiz Antonio; Dobner, Taise; Stobbe, Júlio César; Pomatti, Gabriela; Telles, Cristina Trevizan

2016-08-08

to estimate the prevalence of hypoalbuminemia in hospitalized elders, related to socio-demographic variables, nutritional status and length of stay. crosscutting study with 200 patients hospitalized in a large hospital in the South of Brazil during three months. Evaluations, lab tests and interviews through questionnaires were performed. the average albuminemia was 2,9 ± 0,5g/dL. Hypoalbuminemia was diagnosed in 173 subjects (87%) and was absent in 27 (13%) that have normal albuminemia (p=0,000). After six days of hospitalization, the prevalence of low levels grew significantly to 90% (p=0,002), average 2,7 ± 0,5g/dL. Using the Mini Nutritional Assessment, it was observed that 41 patients were malnourished and from those, 40 had hypoalbuminemia. the prevalence of hypoalbuminemia proved to be high, in approx. nine in ten elders, and the nutritional status and the length of stay proved to be related to the decrease of serum albumin levels. Thus, it is suggested that monitoring albumin levels should be done to evaluate the risk that the patient has to develop malnutrition and other complications during hospital stays. estimar a prevalência de hipoalbuminemia em idosos hospitalizados, em relação às variáveis sociodemográficas, estado nutricional e tempo de internação. estudo transversal, com 200 pacientes internados em hospital de grande porte do sul do Brasil, durante o período de três meses. Foram realizadas avaliações, análise de exames laboratoriais e entrevista através de questionário. a média de albuminemia foi 2,9 ± 0,5g/dL. O diagnóstico de hipoalbuminemia, foi encontrado em 173 sujeitos (87%), e não revelado em 27 (13%), que apresentaram albuminemia normal (p=0,000). Constatou-se que após seis dias de internação a prevalência de níveis baixos aumentou significativamente para 90% (p=0,002), com média de 2,7 ± 0,5g/dL. Utilizando-se a Mini Avaliação Nutricional, observou-se que 41 pacientes estavam desnutridos, e que destes, 40 apresentavam hipoalbuminemia. a prevalência de hipoalbuminemia mostrou-se elevada, acometendo aproximadamente nove entre dez idosos, sendo que o estado nutricional, da mesma maneira que o tempo de internação , está relacionado à diminuição dos níveis de albumina sérica. Assim, sugere-se monitorar os níveis de albuminemia para avaliar o risco que o paciente tem de desenvolver desnutrição e demais complicações durante a internação hospitalar. estimar la prevalencia de hipoalbuminemia en ancianos hospitalizados, considerando las variables sociodemográficas, estado nutricional y tiempo de internación. estudio transversal, en 200 pacientes internados en hospital de gran porte del sur de Brasil, durante un período de tres meses. Fueron realizadas evaluaciones, análisis de exámenes de laboratorio y se realizó una entrevista usando un cuestionario. el promedio de albuminemia fue 2,9 ± 0,5g/dL. El diagnóstico de hipoalbuminemia, fue encontrado en 173 sujetos (87%), y no revelado en 27 (13%), que presentaron albuminemia normal (p=0,000). Se constató que después de seis días de internación la prevalencia de niveles bajos aumentó significativamente para 90% (p=0,002), con promedio de 2,7 ± 0,5g/dL. Utilizando la Mini Evaluación Nutricional, se observó que 41 pacientes estaban desnutridos, y que de estos, 40 presentaban hipoalbuminemia. la prevalencia de hipoalbuminemia se mostró elevada, afectando aproximadamente nueve entre diez ancianos, siendo que el estado nutricional, de la misma manera que el tiempo de internación, está relacionado a la disminución de los niveles de albúmina sérica. Así, se sugiere monitorizar los niveles de albuminemia para evaluar el riesgo que el paciente tiene de desarrollar desnutrición y demás complicaciones durante la internación hospitalaria.

Patient Safety Incidents and Nursing Workload.

PubMed

Carlesi, Katya Cuadros; Padilha, Kátia Grillo; Toffoletto, Maria Cecília; Henriquez-Roldán, Carlos; Juan, Monica Andrea Canales

2017-04-06

to identify the relationship between the workload of the nursing team and the occurrence of patient safety incidents linked to nursing care in a public hospital in Chile. quantitative, analytical, cross-sectional research through review of medical records. The estimation of workload in Intensive Care Units (ICUs) was performed using the Therapeutic Interventions Scoring System (TISS-28) and for the other services, we used the nurse/patient and nursing assistant/patient ratios. Descriptive univariate and multivariate analysis were performed. For the multivariate analysis we used principal component analysis and Pearson correlation. 879 post-discharge clinical records and the workload of 85 nurses and 157 nursing assistants were analyzed. The overall incident rate was 71.1%. It was found a high positive correlation between variables workload (r = 0.9611 to r = 0.9919) and rate of falls (r = 0.8770). The medication error rates, mechanical containment incidents and self-removal of invasive devices were not correlated with the workload. the workload was high in all units except the intermediate care unit. Only the rate of falls was associated with the workload. identificar a relação entre a carga de trabalho da equipe de enfermagem e a ocorrência de incidentes de segurança dos pacientes ligados aos cuidados de enfermagem de um hospital público no Chile. pesquisa transversal analítica quantitativa através de revisão de prontuários médicos. A estimativa da carga de trabalho em Unidade de Terapia Intensiva (UTI) foi realizada utilizando o Índice de Intervenções Terapêuticas-TISS-28 e para os outros serviços, foram utilizados os cocientes enfermeira/paciente e auxiliar de enfermagem/ paciente. Foram feitas análises univariada descritiva e multivariada. Para a análise multivariada utilizou-se análise de componentes principais e correlação de Pearson. foram analisados 879 prontuáriosclínicos de pós-alta e a carga de trabalho de 85 enfermeiros e 157 auxiliares de enfermagem. A taxa global de incidentes foi de 71,1%. Foi encontrada uma alta correlação positiva entre as variáveis de carga de trabalho (r = 0,9611 para r = 0,9919) e a taxa de quedas (r = 0,8770). As taxas de erro de medicação, incidentes de contenção mecânica e auto remoção de dispositivos invasivos não foram correlacionadas com a carga de trabalho. a carga de trabalho foi elevada em todas as unidades, exceto na unidade de cuidados intermédios. Apenas a taxa de quedas foi associada com a carga de trabalho. identificar la relación entre la carga laboral del equipo de enfermería y la ocurrencia de incidentes de seguridad del paciente relacionados con los cuidados de enfermería en un hospital público de Chile. investigación cuantitativa, analítica, transversal, realizada por revisión de fichas clínicas. La estimación de carga laboral en las Unidades de Cuidados Intensivos (UCI) se realizó utilizando el Índice de Intervenciones Terapéuticas (TISS-28) y, para el resto de los servicios, por la relación enfermera/paciente y auxiliar/paciente. Se realizó análisis descriptivo univariado y multivariado. Para el análisis multivariado se utilizó análisis de componentes principales y el test de correlación de Pearson. se revisaron 879 fichas clínicas posteriores al alta y la carga laboral de 85 enfermeras y 157 auxiliares de enfermería. La tasa global de incidentes fue 71,1%. Se encontró correlación positiva alta entre las variables de carga laboral (r = 0,9611 a r = 0,9919) y tasa de caídas (r = 0,8770). Las tasas de error de medicación, incidente por contención mecánica y auto retiro de invasivos no se correlacionaron con la carga laboral. la carga laboral fue elevada en todas las unidades a excepción de la unidad de cuidados intermedios. Sólo la tasa de caídas se asoció a la carga laboral.

A BMI-adjusted ultra-low-dose CT angiography protocol for the peripheral arteries-Image quality, diagnostic accuracy and radiation exposure.

PubMed

Schreiner, Markus M; Platzgummer, Hannes; Unterhumer, Sylvia; Weber, Michael; Mistelbauer, Gabriel; Loewe, Christian; Schernthaner, Ruediger E

2017-08-01

To investigate radiation exposure, objective image quality, and the diagnostic accuracy of a BMI-adjusted ultra-low-dose CT angiography (CTA) protocol for the assessment of peripheral arterial disease (PAD), with digital subtraction angiography (DSA) as the standard of reference. In this prospective, IRB-approved study, 40 PAD patients (30 male, mean age 72 years) underwent CTA on a dual-source CT scanner at 80kV tube voltage. The reference amplitude for tube current modulation was personalized based on the body mass index (BMI) with 120 mAs for [BMI≤25] or 150 mAs for [2570%) was assessed by two readers independently and compared to subsequent DSA. Radiation exposure was assessed with the computed tomography dose index (CTDIvol) and the dosis-length product (DLP). Objective image quality was assessed via contrast- and signal-to-noise ratio (CNR and SNR) measurements. Radiation exposure and image quality were compared between the BMI groups and between the BMI-adjusted ultra-low-dose protocol and the low-dose institutional standard protocol (ISP). The BMI-adjusted ultra-low-dose protocol reached high diagnostic accuracy values of 94% for Reader 1 and 93% for Reader 2. Moreover, in comparison to the ISP, it showed significantly (p<0.001) lower CTDIvol (1.97±0.55mGy vs. 4.18±0.62 mGy) and DLP (256±81mGy x cm vs. 544±83mGy x cm) but similar image quality (p=0.37 for CNR). Furthermore, image quality was similar between BMI groups (p=0.86 for CNR). A CT protocol that incorporates low kV settings with a personalized (BMI-adjusted) reference amplitude for tube current modulation and iterative reconstruction enables very low radiation exposure CTA, while maintaining good image quality and high diagnostic accuracy in the assessment of PAD. Copyright © 2017 Elsevier B.V. All rights reserved.

Progress in molecular diagnosis of Charcot-Marie-Tooth-disease type 1 (CMT 1, HMSN I) and hereditary neuropathy with liability to pressure palsies (HNPP) by fluorescence in situ hybridization (FISH)-detection of a potential genetic mosaicism

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

Bathke, K.; Liehr. T.; Ekici, A.

1994-09-01

We tested 20 CMT 1 patients characterized according to the criteria of the European CMT consortium by Southern hybridization of MspI restricted genomic DNA with probes pVAW409R1, pVAW412Hec and pEW401HE. In 11 of the 20 CMT 1 cases (55%), we observed a duplication in 17q11.2; one patient had a dinucleotide insertion in exon 6 of the PO-gene (5%). One HNPP case had a typical 17p11.2 deletion. Analysis of CA-repeats was performed with primers RM11GT and Mfd41; SSCP-analysis of the PO, PMP22 and Cx32-genes is in progress. FISH was carried out with probe pVAW409R1. 125 interphase nuclei were analyzed for eachmore » proband by counting the signals per nucleus. Normal cells show a characteristic distribution of signals: 1 signal in 5.9% of nuclei, 2 in 86.3% and 3 in 7.8%. A duplication is indicated by a shift to 3 signals in more than approximately 60% and 2 in less than 25% of the nuclei. In contrast, the 17p11.2 deletion of the HNPP patient shifts to 82.4% of nuclei with a single hybridization signal versus 14.4% with 2 signals. We detected one case with significantly abnormal distribution of interphase nuclei hybridization signals compared to cultures of normal cells and to those with 17p11.2 duplication or deletion: 3.2% nuclei revealed 1 signal, 48.0% two signals and 48.8% 3 signals, indicating a pathogenic but moderate dosis increase compared to the throughout duplicated cases. FISH with probe pVAW409R1 is a versatile tool to detect the HNPP deletion both in interphase nuclei and in metaphase chromosomes. In CMT 1 disease interphase nuclei are required for FISH analysis due to the small duplication of 1.5 Mbp. In contrast to Southern techniques, FISH is able to detect genetic mosaicism.« less

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

Gonzalez-Sprinberg, G; Piriz, G

Purpose: To optimize the dose in bladder and rectum and show the different shapes of the isodose volumes in Co60-HDR brachytherapy, considering different utero and vaginal sources dwell ratio times (TU:TV). Methods: Besides Ir192-HDR, new Co60-HDR sources are being incorporated. We considered different TU:TV times and computed the dosis in bladder, rectum and at the reference points of the Manchester system. Also, we calculated the isodose volume and shape in each case. We used a EZAG-BEBIG Co0.A86 model with TPS HDRplus3.0.4. and LCT42-7, LCT42-2(R,L) applicators. A reference dose RA= 1.00 Gy was given to the A-right point. We considered themore » TU:TV dwell time ratios 1:0.25, 1:0.33, 1:0.5, 1:1, 1:2, 1:3, and 1:4. Given TU:TV, the stop time at each dwell position is fixed for each applicator. Results: Increasing TU:TV systematically results in a decreasing of the dose in bladder and rectum, e.g. 9% and 27% reduction were found in 1:0.25 with respect to 1:1, while 12% and 34% increase were found in 1:4 with respect to 1:1. Also, the isodose volume parameters height (h), width (w), thickness (t) and volume (hwt) increased from the 1:0.25 case to the 1:4 value: hwt is 25% lower and 31% higher than the 1:1 reference volume in these cases. Also w decreased for higher TU:TV and may compromise the tumoral volume coverage, decreasing 17% in the 1:0.25 case compared to the 1:1 case. The shape of the isodose volume was obtained for the different TU:TV considered. Conclusion: We obtained the shape of isodose volumes for different TU:TV values in gynecological Co60-HDR. We studied the dose reduction in bladder and rectum for different TU:TV ratios. The volume parameters and hwt are strongly dependent on this ratio. This information is useful for a quantitative check of the TPS and as a starting point towards optimization.« less

Low completion rate of hepatitis B vaccination in female sex workers.

PubMed

Magalhães, Rosilane de Lima Brito; Teles, Sheila Araújo; Reis, Renata Karina; Galvão, Marli Teresinha Gimeniz; Gir, Elucir

2017-01-01

to assess predictive factors for noncompletion of the hepatitis B vaccination schedule in female sex workers in the city of Teresina, Northeastern Brazil. 402 women were interviewed and, for those who did not wish to visit specialized sites, or did not know their hepatitis B vaccination status, the vaccine was offered at their workplaces. Bi- and multivariate analyses were performed to identify potential predictors for noncompletion of the vaccination schedule. of the 284 women eligible for vaccination, 258 (90.8%) received the second dose, 157/258 (60.8%) and 68/258 (26.3%) received the second and third doses, respectively. Working at clubs and consuming illicit drugs were predictors for noncompletion of the vaccination schedule. the high acceptability of the vaccine's first dose, associated with low completion rates of the vaccination schedule in sex workers, shows the need for more persuasive strategies that go beyond offering the vaccine at their workplaces. avaliar fatores preditores de não completude do esquema vacinal contra hepatite B em mulheres que se prostituem em Teresina, Nordeste do Brasil. Um total de 402 mulheres foi entrevistado e, para as que se negaram a irem a lugares especializados, ou desconheciam sua situação vacinal contra hepatite B, a vacina foi oferecida no local do trabalho. Análises bi e multivariadas foram realizadas para identificar potenciais preditores de não completude do esquema vacinal. Das 284 mulheres elegíveis para vacinação, 258 (90,8%) receberam a primeira dose, 157/258 (60,8%) e 68/258 (26,3%) receberam a segunda e terceira doses. Trabalhar em boates e consumir drogas ilícitas foram preditores de não completude do esquema vacinal (p<0,05). A elevada aceitabilidade da primeira dose da vacina, associada à baixa completude do esquema vacinal em profissionais do sexo, evidencia a necessidade de estratégia mais persuasiva que vá além da oferta da vacina no local de trabalho.

PubMed

Caamaño Navarrete, Felipe; Delgado Floody, Pedro; Jerez Mayorga, Daniel; Osorio Poblete, Aldo

2016-09-20

Introducción: bajos niveles de actividad física, moderada y vigorosa, son un factor de riesgo conductual importante en la obesidad en niños.Objetivo: el objetivo del estudio fue determinar el estado nutricional y la condición física de escolares, comparando los resultados obtenidos por género, obesidad y rendimiento físico.Material y métodos:578 escolares: 308 hombres de 11,22 ± 1,93 años y 270 mujeres de 10,93 ± 1,92 años participaron en la investigación. Fueron evaluados: índice de masa corporal (IMC), porcentaje de masa grasa (%MG), contorno de cintura (CC), razón cintura-estatura (RCE) y rendimiento físico según los test del Estudio Nacional de Educación Física de la Agencia de Calidad de la Educación de Chile.Resultados: el %MG fue mayor en la mujeres (p < 0,001). En el test de abdominales y en el de Navette el rendimiento fue mayor en los hombres, y en el test de flexo-extensiones de brazo el rendimiento fue mayor en las mujeres (p < 0,05). Los escolares en categoría de obeso presentaron inferiores resultados en los test de: abdominales, salto largo, flexo-extensiones de brazo y Navette (p < 0,001). El VO2MAX fue menor en los sujetos con obesidad (p < 0,001). Los estudiantes que necesitan mejorar 3 o 4 test presentan mayor RCE (p < 0,001) y %MG (p < 0,001). Existe una asociación negativa entre la RCE y el VO2MAX (-0,543, p < 0,001).Conclusiones: existe una elevada prevalencia de sobrepeso y obesidad. Además, se aprecia un bajo rendimiento físico asociado a esta condición. Los escolares que necesitan mejorar 3 o 4 test de la condición física presentan mayores promedios de %MG y RCE; esta última variable es un potente indicador de riesgo cardiovascular.

Impacto metabólico e inflamatorio de una comida rica en grasas saturadas y su relación con la obesidad abdominal.

PubMed

Alayón, Alicia Norma; Rivadeneira, Ana Patricia; Herrera, Carlos; Guzmán, Heidy; Arellano, Dioneris; Echeverri, Isabella

2018-05-01

Introducción. La etapa posprandial se asocia con el incremento de marcadores relacionados con el riesgo cardiovascular, cuya intensidad depende del estado metabólico.Objetivo. Determinar el impacto de la ingestión de una comida rica en grasas saturadas sobre el perfil metabólico e inflamatorio y su relación con la obesidad abdominal.Materiales y métodos. Se hizo un ensayo clínico en 42 individuos (21 con obesidad abdominal). Se midieron, en sangre, la glucosa, la insulina, el perfil lipídico, la proteína C reactiva, los lipopolisacáridos y la interleucina 6, en ayunas y después de la ingestión.Resultados. Además de la obesidad, se registró la presencia de resistencia a la insulina y de niveles elevados de triacilglicéridos y proteína C reactiva en ayunas. Asimismo, se detectaron niveles posprandiales más elevados de glucosa, insulina y triacilglicéridos. La interleucina 6 disminuyó en el grupo de personas sin obesidad y los lipopolisacáridos aumentaron en ambos grupos.Conclusión. La ingestión de una comida rica en grasas saturadas produjo un mayor impacto en las variables glucémicas en el grupo con obesidad y, aunque afectó de forma similar los lípidos en ambos grupos, el incremento de triacilglicéridos fue mayor en presencia de una concentración basal elevada y promovió el aumento de lipopolisacáridos. El estado inflamatorio basal y posprandial afectó en mayor medida al grupo con obesidad. El momento posprandial reflejó el estado más frecuente de los individuos en un día normal y permitió evidenciar la capacidad de respuesta metabólica frente a la ingestión de alimentos, así como los estados tempranos de riesgo metabólico.

Fiber-optic components for optical communicatios and sensing =

NASA Astrophysics Data System (ADS)

Marques, Carlos Alberto Ferreira

Nos ultimos anos, a Optoelectronica tem sido estabelecida como um campo de investigacao capaz de conduzir a novas solucoes tecnologicas. As conquistas abundantes no campo da optica e lasers, bem como em comunicacoes opticas tem sido de grande importancia e desencadearam uma serie de inovacoes. Entre o grande numero de componentes opticos existentes, os componentes baseados em fibra optica sao principalmente relevantes devido a sua simplicidade e a elevada de transporte de dados da fibra optica. Neste trabalho foi focado um destes componentes opticos: as redes de difraccao em fibra optica, as quais tem propriedades opticas de processamento unicas. Esta classe de componentes opticos e extremamente atraente para o desenvolvimento de dispositivos de comunicacoes opticas e sensores. O trabalho comecou com uma analise teorica aplicada a redes em fibra e foram focados os metodos de fabricacao de redes em fibra mais utilizados. A inscricao de redes em fibra tambem foi abordado neste trabalho, onde um sistema de inscricao automatizada foi implementada para a fibra optica de silica, e os resultados experimentais mostraram uma boa aproximacao ao estudo de simulacao. Tambem foi desenvolvido um sistema de inscricao de redes de Bragg em fibra optica de plastico. Foi apresentado um estudo detalhado da modulacao acustico-optica em redes em fibra optica de silica e de plastico. Por meio de uma analise detalhada dos modos de excitacao mecanica aplicadas ao modulador acustico-optico, destacou-se que dois modos predominantes de excitacao acustica pode ser estabelecidos na fibra optica, dependendo da frequencia acustica aplicada. Atraves dessa caracterizacao, foi possivel desenvolver novas aplicacoes para comunicacoes opticas. Estudos e implementacao de diferentes dispositivos baseados em redes em fibra foram realizados, usando o efeito acustico-optico e o processo de regeneracao em fibra optica para varias aplicacoes tais como rapido multiplexador optico add-drop, atraso de grupo sintonizavel de redes de Bragg, redes de Bragg com descolamento de fase sintonizaveis, metodo para a inscricao de redes de Bragg com perfis complexos, filtro sintonizavel para equalizacao de ganho e filtros opticos notch ajustaveis.

Atomic layer deposition of metal oxide by non-aqueous sol-gel chemistry =

NASA Astrophysics Data System (ADS)

Marichy, Catherine

O trabalho apresentado neste manuscrito foi desenvolvido no ambito do programa doutoral intitulado “Deposicao de Camadas Atomicas (ALD) de oxido de metais por sol-gel nao-aquoso”. O objectivo deste trabalho foi a preparacao de hetero-estruturas funcionais por ALD e a sua caracterizacao. Foi desenvolvido um novo processo de deposicao de oxido de estanho a temperatura baixa-moderada, utilizando um metodo ALD nao-aquoso, o qual foi aplicado com sucesso ao revestimento controlado das paredes internas e externas de nanotubos de carbono. Uma vez que a preparacao de nanomateriais funcionais requer uma elevada exatidao do processo de deposicao, foi demonstrada a deposicao precisa de filmes que se adaptem a forma do substrato ou de filmes nano-estruturados constituidos por particulas em varios substratos. Alem disso, foram depositados com grande exatidao varios oxidos de metal em nanotubos de carbono e demonstrou-se a possibilidade de ajustar o revestimento feito por ALD atraves do controlo da funcionalizacao da superficie do substrato nano-estruturado de carbono. As hetero-estruturas obtidas foram posteriormente aplicadas como sensores de gases. O melhoramento verificado na sensibilidade foi atribuido a formacao de heterojuncoes p-n entre o filme de oxido de metais e o suporte. O trabalho desenvolvido tendo como objetivo o controlo do revestimento por ALD atraves da funcionalizacao da superficie do suporte e certamente de interesse para o design de hetero-estruturas funcionais baseadas em substratos de carbono. De facto, durante o ultimo periodo do programa de doutoramento, este conceito foi alargado a funcionalizacao e revestimento com oxidos de metal de fibras de carbono preparadas por “electrospinning”, de forma a melhorar a estabilidade e a atividade eletrocatalitica de catalisadores a base de Pt. Este trabalho foi realizado maioritariamente na Universidade de Aveiro mas tambem na Universidade Nacional de Seul e beneficiou de varias colaboracoes internacionais devido a natureza multidisciplinar da area de investigacao em que esta inserido.

Nursing appointment and cardiometabolic control of diabetics: a randomized clinical trial.

PubMed

Teston, Elen Ferraz; Arruda, Guilherme Oliveira de; Sales, Catarina Aparecida; Serafim, Deise; Marcon, Sonia Silva

2017-01-01

to verify the effect of nursing appointment on cardiometabolic profile of people with Diabetes Mellitus type 2. randomized controlled trial, developed with 134 individuals chosen for two groups: intervention and control. The intervention consisted of three nursing appointments alternated bimonthly, with two phone calls, over five months. The control group received usual care offered by the Health Unit. Data were collected through semi-structured interviews before and after the intervention, in addition to conducting laboratory tests. after the intervention, a significant difference was shown in the amount of glycated hemoglobin (p = 0.006) and in the systolic blood pressure (p = 0.031), which were higher in the control group. besides being low-cost and easy to develop on the monitoring routine of people with diabetes, the intervention performed influenced positively the biochemical profile. verificar o efeito da consulta de enfermagem sobre o perfil cardiometabólico de pessoas com Diabetes Mellitus tipo 2. ensaio clínico controlado e randomizado, desenvolvido com 134 indivíduos sorteados para dois grupos: intervenção e controle. A intervenção consistiu em três consultas de enfermagem bimensais alternadas, com duas ligações telefônicas, ao longo de cinco meses. O grupo-controle recebeu os cuidados habituais oferecidos pela Unidade de Saúde. Os dados foram coletados mediante entrevistas semiestruturadas antes e após a intervenção, além da realização de exames laboratoriais. após a intervenção, foi evidenciada diferença significativa no valor da hemoglobina glicada (p=0,006) e da pressão arterial sistólica (p=0,031), que se mostraram mais elevadas no grupo-controle. a intervenção realizada, além de ser de baixo custo e de fácil desenvolvimento na rotina de acompanhamento da pessoa com diabetes, influenciou positivamente a melhora do perfil bioquímico.

Factors associated with poor sleep quality in women with cancer.

PubMed

Mansano-Schlosser, Thalyta Cristina; Ceolim, Maria Filomena

2017-03-02

to analyze the factors associated with poor sleep quality, its characteristics and components in women with breast cancer prior to surgery for removing the tumor and throughout the follow-up. longitudinal study in a teaching hospital, with a sample of 102 women. The following were used: a questionnaire for sociodemographic and clinical characterization, the Pittsburgh Sleep Quality Index; the Beck Depression Inventory; and the Herth Hope Scale. Data collection covered from prior to the surgery for removal of the tumor (T0) to T1, on average 3.2 months; T2, on average 6.1 months; and T3, on average 12.4 months. Descriptive statistics and the Generalized Estimating Equations model were used. depression and pain contributed to the increase in the score of the Pittsburgh Sleep Quality Index, and hope, to the reduction of the score - independently - throughout follow-up. Sleep disturbances were the component with the highest score throughout follow-up. the presence of depression and pain, prior to the surgery, contributed to the increase in the global score of the Pittsburgh Sleep Quality Index, which indicates worse quality of sleep throughout follow-up; greater hope, in its turn, influenced the reduction of the score of the Pittsburgh Sleep Quality Index. analizar los factores asociados a la mala calidad del sueño, sus características y componentes en mujeres con cáncer de mama, antes de la cirugía de retirada del tumor y a lo largo del seguimiento. estudio longitudinal, en hospital universitario con muestra de 102 mujeres. Fueron utilizados: un cuestionario de caracterización sociodemográfica y clínica; el Índice de Calidad del Sueño de Pittsburgh; el Inventario de Depresión de Beck; y la Escala de Esperanza de Herth. La recolección comprendió los momentos: antes de la cirugía de retirada del tumor (T0), en (T1) en promedio 3,2 meses, en (T2) en promedio 6,1 meses y en (T3) en promedio 12,4 meses. Se utilizó estadística descriptiva y el modelo de Ecuaciones de Estimación Generalizada. la depresión y el dolor contribuyeron para el aumento del puntaje del Índice de Calidad del Sueño de Pittsburgh y la esperanza para la reducción del puntaje, de manera independiente, a lo largo del seguimiento. Los trastornos del sueño fueron el componente con puntuación más elevada, a lo largo del seguimiento. la presencia de la depresión y del dolor, previos a la cirugía, contribuyeron para el aumento del puntaje global del Índice de Calidad del Sueño de Pittsburgh, lo que indica peor calidad del sueño, a lo largo del seguimiento y, la mayor esperanza, a su vez, influenció en la reducción del puntaje del Índice de Calidad del Sueño de Pittsburgh. analisar os fatores associados à má qualidade do sono, suas características e componentes em mulheres com câncer de mama antes da cirurgia de retirada do tumor e ao longo do seguimento. estudo longitudinal, em hospital universitário com amostra de 102 mulheres. Foram utilizados: questionário de caracterização sociodemográfica e clínica, Índice de Qualidade do Sono de Pittsburgh; Inventário de Depressão de Beck; Escala de Esperança de Herth. Coleta compreendeu antes da cirurgia de retirada do tumor (T0) em T1, em média 3,2 meses; T2, em média 6,1 meses; T3, em média 12,4 meses. Utilizou-se estatística descritiva e o modelo de Equações de Estimação Generalizada. a depressão e a dor contribuíram para o aumento do escore do Índice de Qualidade de Sono de Pittsburgh, e a esperança, para a redução do escore, de maneira independente, ao longo do seguimento. Os transtornos do sono foram o componente com pontuação mais elevada, ao longo do seguimento. a presença de depressão e de dor, previamente à cirurgia, contribuiu para o aumento do escore global do Índice de Qualidade do Sono de Pittsburgh, o que indica pior qualidade do sono, ao longo do seguimento e, a maior esperança, por sua vez, influenciou na redução do escore do Índice de Qualidade do Sono de Pittsburgh.

Factors associated with the healing of complex surgical wounds in the breast and abdomen: retrospective cohort study.

PubMed

Borges, Eline Lima; Pires, José Ferreira; Abreu, Mery Natali Silva; Lima, Vera Lúcia de Araújo; Silva, Patrícia Aparecida Barbosa; Soares, Sônia Maria

2016-10-10

to estimate the healing rate of complex surgical wounds and its associated factors. retrospective cohort study from 2003 to 2014 with 160 outpatients of a Brazilian university hospital. Data were obtained through consultation of the medical records. Survival function was estimated using the Kaplan-Meier method and Cox regression model to estimate the likelihood of the occurrence of healing. the complex surgical wound healing rate was 67.8% (95% CI: 60.8-74.9). Factors associated with a higher likelihood of wound healing were segmentectomy/quadrantectomy surgery, consumption of more than 20 grams/day of alcohol, wound extent of less that 17.3 cm2 and the length of existence of the wound prior to outpatient treatment of less than 15 days, while the use of hydrocolloid covering and Marlex mesh were associated with a lower likelihood of healing. the wound healing rate was considered high and was associated with the type of surgical intervention, alcohol consumption, type of covering, extent and length of wound existence. Preventive measures can be implemented during the monitoring of the evolution of the complex surgical wound closure, with possibilities of intervention in the modifiable risk factors. estimar a taxa de cicatrização de ferida cirúrgica complexa e seus fatores associados. coorte retrospectiva de 2003 a 2014 com 160 pacientes ambulatoriais de um hospital universitário brasileiro. Os dados foram obtidos por meio de consulta aos prontuários médicos. Função de sobrevida foi estimada pelo método de Kaplan-Meier e modelo de regressão de Cox para estimação do risco de ocorrência da cicatrização. a taxa de cicatrização da ferida cirúrgica complexa foi 67,8% (IC 95%: 60,8-74,9). Os fatores associados a um maior risco de cicatrização da ferida foram cirurgia de setorectomia / quadrantectomia, consumo de mais de 20 gramas/dia de etanol, extensão da ferida menor que 17,3 cm2 e tempo de existência da ferida pré-tratamento ambulatorial inferior a 15 dias, enquanto uso de cobertura hidrocoloide e tela de Marlex estiveram associados a um menor risco de cicatrização. a taxa de cura da ferida foi considerada elevada, e esteve associada ao tipo de intervenção cirúrgica, consumo de etanol, tipo de cobertura, extensão e tempo de existência da ferida. Condutas preventivas podem ser implementadas durante o acompanhamento da evolução do fechamento da ferida cirúrgica complexa, com possibilidades de intervenção nos fatores de risco modificáveis. estimar la tasa de cicatrización de herida quirúrgica compleja y sus factores asociados. cohorte retrospectivo de 2003 a 2014 con 160 pacientes de ambulatorio de un hospital universitario brasileño. Los datos fueron obtenidos por medio de consulta a las fichas médicas. La función de supervivencia fue estimada por el método de Kaplan-Meier y el modelo de regresión de Cox para estimar el riesgo de ocurrencia de cicatrización. la tasa de cicatrización de la herida quirúrgica compleja fue 67,8% (IC 95%: 60,8-74,9). Los factores asociados a un mayor riesgo de cicatrización de la herida fueron cirugía de sectorectomía / cuadrantectomía, consumo de más de 20 gramos/día de etanol, extensión de la herida menor que 17,3 cm2 y tiempo de existencia de la herida antes del tratamiento en ambulatorio inferior a 15 días; en lo que se refiere al uso de cubrimiento hidrocoloide y tela de Marlex estuvieron asociados a un menor riesgo de cicatrización. la tasa de cura de la herida fue considerada elevada, y estuvo asociada al tipo de intervención quirúrgica, consumo de etanol, tipo de cubrimiento, extensión y tiempo de existencia de la herida. Conductas preventivas pueden ser implementadas durante el acompañamiento de la evolución del cierre de la herida quirúrgica compleja, con posibilidades de intervenir sobre los factores de riesgo modificables.

Workload and associated factors: a study in maritime port in Brazil.

PubMed

Cezar-Vaz, Marta Regina; Bonow, Clarice Alves; Almeida, Marlise Capa Verde de; Sant'Anna, Cynthia Fontella; Cardoso, Leticia Silveira

2016-11-28

to identify the effect of the mental, physical, temporal, performance, total effort and frustration demands in the overall workload, and in the same way analyze the global burden of port labor and associated factors that contribute most to their decrease or increase. a cross-sectional, quantitative study, developed with 232 dock workers. For data collection, a structured questionnaire with descriptive, occupational, smoking and illicit drug use variables was applied, as well as variables on the load on the tasks undertaken at work, based on the questionnaire NASA Task Load Index. For data analysis, we used the analysis of the Poisson regression model. the demands physical demand and total effort showed greater effect on the overall workload, indicating high overall load on port work (134 employees - 58.8%). The following remained associated statistically with high levels of workload: age (p = 0.044), to be employee of the wharfage (p = 0.006), work only at night (p = 0.025), smoking (p = 0.037) and use of illegal drugs (p = 0.029). the workload in this type of activity was high, and the professional category and work shift the factors that contributed to the increase, while the age proved to be a factor associated with a decrease. identificar o efeito das demandas mental, física, temporal, de desempenho, esforço total e frustração na carga global de trabalho, da mesma maneira que analisar a carga global de trabalho portuário e fatores associados que mais contribuem para sua diminuição ou aumento. estudo transversal, quantitativo, desenvolvido com 232 trabalhadores portuários. Para a coleta de dados, foi aplicado um questionário estruturado com variáveis de caracterização, ocupacional, tabagismo e uso de drogas ilícitas, além de variáveis sobre a carga nas tarefas desenvolvidas no trabalho, com base no questionário NASA Task Load Index. Para análise dos dados, utilizou-se a análise do modelo de regressão de Poisson. as demandas exigência física e esforço total apresentaram maior efeito sobre a carga global de trabalho, indicando elevada carga global no trabalho portuário (134 trabalhadores - 58,8%). Permaneceram associados, estatisticamente, com níveis elevados da carga de trabalho: idade (p = 0,044), ser trabalhador da capatazia (p = 0,006), trabalhar somente no período noturno (p = 0,025), tabagismo (p = 0,037) e uso de drogas ilícitas (p = 0,029). a carga de trabalho, nesse tipo de atividade, foi alta, sendo a categoria profissional e o turno de trabalho os fatores que contribuíram para o aumento, enquanto a idade mostrou-se fator associado à sua diminuição. identificar el efecto de las demandas mentales, físicas de tiempo y de desempeño, el esfuerzo total y la frustración en la carga de trabajo global, al mismo tiempo que se analizan la carga global de trabajo portuario y los factores asociados que contribuyen principalmente a su disminución o aumento. estudio transversal cuantitativo desarrollado con 232 trabajadores portuarios. Para la recolección de datos se aplicó un cuestionario estructurado con variables de caracterización, ocupacionales, tabaquismo y uso de drogas ilícitas así como también variables sobre la carga en las tareas desarrolladas en el trabajo, en base en el cuestionario NASA Task Load Index. Para el análisis de los datos se utilizó análisis de regresión de Poisson. las demandas exigencia física y esfuerzo total presentaron mayor efecto sobre la carga global de trabajo, indicando una elevada carga global en el trabajo portuario (134 trabajadores 58,8%). Estaban asociados estadísticamente con niveles elevados de la carga de trabajo: la edad (p = 0,044); ser trabajador de la capatacía (p = 0,006); trabajar solamente en el periodo nocturno (p = 0,025); tabaquismo (p = 0,037); y uso de drogas ilícitas (p = 0,029). la carga de trabajo en este tipo de actividad fue alta, siendo la categoría profesional y el turno de trabajo los factores que contribuyeron para este aumento, mientras que la edad fue un factor asociado a su disminución.

Evaluating cis-2,6-Dimethylpiperidide (cis-DMP) as a Base Component in Lithium-Mediated Zincation Chemistry

PubMed Central

Armstrong, David R; Garden, Jennifer A; Kennedy, Alan R; Leenhouts, Sarah M; Mulvey, Robert E; O'Keefe, Philip; O'Hara, Charles T; Steven, Alan

2013-01-01

Most recent advances in metallation chemistry have centred on the bulky secondary amide 2,2,6,6-tetramethylpiperidide (TMP) within mixed metal, often ate, compositions. However, the precursor amine TMP(H) is rather expensive so a cheaper substitute would be welcome. Thus this study was aimed towards developing cheaper non-TMP based mixed-metal bases and, as cis-2,6-dimethylpiperidide (cis-DMP) was chosen as the alternative amide, developing cis-DMP zincate chemistry which has received meagre attention compared to that of its methyl-rich counterpart TMP. A new lithium diethylzincate, [(TMEDA)LiZn(cis-DMP)Et2] (TMEDA=N,N,N′,N′-tetramethylethylenediamine) has been synthesised by co-complexation of Li(cis-DMP), Et2Zn and TMEDA, and characterised by NMR (including DOSY) spectroscopy and X-ray crystallography, which revealed a dinuclear contact ion pair arrangement. By using N,N-diisopropylbenzamide as a test aromatic substrate, the deprotonative reactivity of [(TMEDA)LiZn(cis-DMP)Et2] has been probed and contrasted with that of the known but previously uninvestigated di-tert-butylzincate, [(TMEDA)LiZn(cis-DMP)tBu2]. The former was found to be the superior base (for example, producing the ortho-deuteriated product in respective yields of 78 % and 48 % following D2O quenching of zincated benzamide intermediates). An 88 % yield of 2-iodo-N,N-diisopropylbenzamide was obtained on reaction of two equivalents of the diethylzincate with the benzamide followed by iodination. Comparisons are also drawn using 1,1,1,3,3,3-hexamethyldisilazide (HMDS), diisopropylamide and TMP as the amide component in the lithium amide, Et2Zn and TMEDA system. Under certain conditions, the cis-DMP base system was found to give improved results in comparison to HMDS and diisopropylamide (DA), and comparable results to a TMP system. Two novel complexes isolated from reactions of the di-tert-butylzincate and crystallographically characterised, namely the pre-metallation complex [{(iPr)2N(Ph)C=O}LiZn(cis-DMP)tBu2] and the post-metallation complex [(TMEDA)Li(cis-DMP){2-[1-C(=O)N(iPr)2]C6H4}Zn(tBu)], shed valuable light on the structures and mechanisms involved in these alkali-metal-mediated zincation reactions. Aspects of these reactions are also modelled by DFT calculations. PMID:23955639

Pyclen Tri-n-butylphosphonate Ester as Potential Chelator for Targeted Radiotherapy: From Yttrium(III) Complexation to (90)Y Radiolabeling.

PubMed

Le Fur, Mariane; Beyler, Maryline; Lepareur, Nicolas; Fougère, Olivier; Platas-Iglesias, Carlos; Rousseaux, Olivier; Tripier, Raphaël

2016-08-15

The Y(3+) complex of PCTMB, the tri-n-butyl phosphonate ester of pyclen (3,6,9,15-tetraazabicyclo[9.3.1]pentadeca-1(15),11,13-triene), was synthesized as well as its Ho(3+) and Lu(3+) analogues. X-ray diffraction analyses revealed isomorphous dimeric M2(PCTMB)2·9H2O (M = Y, Ho, Lu) structures that crystallize in the centrosymmetric P1̅ triclinic space group. (1)H NMR and UV studies in aqueous solutions indicated that Y(3+) complexation is fast, being quantitative in 167 min at pH 3.8 and in 13 min at pH 5.5 (25 °C, acetate buffer, I = 0.150 M, [Y(3+)] = [PCTMB] = 0.2 mM). (1)H NMR DOSY and photon correlation spectroscopy experiments evidenced the formation of aggregates in chloroform with a bimodal distribution that changes slightly with concentration (11-24 and 240-258 nm). The behavior of the acid-assisted dissociation of the complex of Y(3+) with PCTMB was studied under pseudo-first-order conditions, and the half-life of the [Y(PCTMB)] complex in 0.5 M HCl at 25 °C was found to be 37 min, a value that decreases to 2.6 min in 5 M HCl. The Y(3+) complex of PCTMB is thermodynamically very stable, with a stability constant of log KY-PCTMB = 19.49 and pY = 16.7 measured by potentiometry. (90)Y complexation studies revealed fast radiolabeling kinetics; optimal radiolabeling conditions were obtained for (90)Y in acetate medium, PCTMB at 10(-4) to 10(-2) M in acetate buffer pH = 4.75, 15 min at 45-60 °C. In vitro stability studies in human serum showed that [(90)Y(PCTMB)] is quite stable, with about 90% of the activity still in the form of the radiotracer at 24 h and 80% from 48 h to 72 h. A comparison with other ligands such as PCTA, DOTA, and DTPA already used for in vivo application shows that [(90)Y(PCTMB)] is an interesting lipophilic and neutral analogue of these reference chelates for therapeutic applications in aqueous and nonaqueous media.

[In Process Citation].

PubMed

Fófano do Lago, Márcia; Chaia Kaippert, Vanessa; Lopes Souto, Débora; Lopes Rosado, Eliane

2016-03-25

Introducción: el tipo de ácido graso de la dieta presenta diferentes efectos sobre la obesidad y sus complicaciones, pero estos efectos pueden verse influenciados por los genes y sus polimorfismos, tales como los receptores activados por el proliferador de los peroxisomas isoforma γ2 (PPARγ2). Además, no está claro si el grado de insaturación de los lípidos posee diferentes efectos en el metabolismo de los lípidos y de la glucosa y, particularmente, en la pérdida de peso. Objetivos: evaluar la influencia de dietas ricas en ácidos grasos poliinsaturados (AGPI) y monoinsaturados (AGMI) en las variables antropométricas y bioquímicas en el peso corporal y el perfil glucémico y lipémico en mujeres obesas con el genotipo Pro12Pro en el gen PPARγ2. Métodos: dieciocho mujeres obesas con genotipo Pro12Pro fueron distribuidas aleatoriamente para una de las dietas, rica en AGPI (n = 8) o AGMI (n = 10). Las variables antropométricas (índice de masa corporal [IMC] y circunferencia de la cintura) y bioquímicas (glucosa, insulina, HOMA-IR, colesterol total, LDL-colesterol, HDL colesterol y triglicéridos) fueron evaluadas antes y después de un periodo de 45 días. Resultados: las variables antropométricas y bioquímicas fueron similares entre los grupos antes y después de la intervención (p > 0,05). El IMC disminuyó después de la ingesta de AGPI (p = 0,01), probablemente debido al menor contenido de lípidos. El AGMI redujo la glucosa (p = 0,03), insulina (p = 0,03) y HOMA-IR (p = 0,02). Conclusión: los AGMI fueron más eficientes para reducir la resistencia a la insulina en mujeres obesas con el genotipo Pro12Pro en el gen PPARγ2, aunque las mujeres presentaran una elevada ingesta de lípidos totales y ácidos grasos saturados.

Associação entre sintomas, veias varicosas e refluxo na veia safena magna ao eco-Doppler

PubMed Central

Seidel, Amélia Cristina; Campos, Mariana Baldini; Campos, Raquel Baldini; Harada, Dérica Sayuri; Rossi, Robson Marcelo; Cavalari, Pedro; Miranda, Fausto

2017-01-01

Resumo Contexto A doença venosa crônica requer avaliação clínica, quantificação dos efeitos hemodinâmicos e definição da distribuição anatômica para decisão diagnóstica e tratamento. Métodos Estudo prospectivo realizado em 2015 com amostra de 1.384 pacientes (2.669 membros) com idade entre 17 e 85 anos, sendo 1.227 do sexo feminino. Nas respostas do questionário aplicado, os sintomas pesquisados eram dor, cansaço, sensação de peso, queimação, câimbras e formigamento. Para a formação dos grupos, foi considerado o número de membros, distribuídos em relação ao gênero, ao índice de massa corporal e à idade. Após a definição grupos e a realização do eco-Doppler para estudo da veia safena magna (VSM), os pacientes foram distribuídos em três grupos (I: sintomas presentes e varizes ausentes, II: sintomas ausentes e varizes presentes e III: sintomas presentes e varizes presentes). A análise estatística utilizou o teste qui-quadrado ou exato de Fisher para verificar a homogeneidade entre os grupos. Em caso de associação com significância de 5%, foi calculada a razão de chances. Resultados Para ambos os gêneros, foi observada chance de insuficiência da VSM 11,2 vezes maior no grupo III. Por sua vez, os casos de obesidade mórbida ocorreram 9,1 vezes mais no mesmo grupo. Além disso, pacientes na faixa etária entre 30 e 50 anos desse grupo apresentaram chance de insuficiência da VSM 43,1 vezes maior. Conclusões A insuficiência da VSM foi significantemente mais frequente no grupo III, tanto globalmente como considerando apenas os casos de obesidade mórbida e a faixa etária mais elevada. PMID:29930616

Medio ambiente y cáncer pediátrico en la Región de Murcia (España): integrando la historia clínica medioambiental en un sistema de información geográfica

PubMed Central

Ortega-García, J.A.; López-Hernández, F.A.; Sobrino-Najul, E.; Febo, I.; Fuster-Soler, J.L.

2016-01-01

Introducción Medio Ambiente y Cáncer Pediátrico (CP) en la Región de Murcia (RM) es un proyecto de investigación, cuya principal meta es el desarrollo de una cuidadosa historia ambiental pediátrica (HAP) y el uso de sistemas de información geográfica (SIG) para crear mapas de incidencia y analizar la distribución geográfica del CP en la RM. El objetivo es presentar la metodología, el estudio descriptivo y los primeros resultados sobre la incidencia espacial y temporal del CP en la RM (España). Material y métodos Estudio descriptivo y de georreferenciación de todos los casos de CP menores de 15 años, diagnosticados entre el 1 de enero de 1998 y el 31 de diciembre de 2009. Se han asociado a cada caso tres direcciones postales, durante el embarazo, en el período posnatal y en el momento del diagnóstico. También se han utilizado las siguientes variables: sexo, fechas de nacimiento y diagnóstico y el diagnóstico patológico. Resultados No se observa un incremento en la tendencia de la incidencia del CP. La tasa cruda de incidencia fue de 14,3 casos por 100.000 niños menores de 15 años. La razón de incidencia estandarizada es más elevada en el noroeste de la RM. El 30% tienen un domicilio previo al diagnóstico distinto al del embarazo. Conclusiones La integración de la información temporal y espacial de la HAP en un SIG permitirá la identificación y el estudio de conglomerados espacio-temporales a través de un sistema de vigilancia medioambiental que ayude a ponderar la importancia de los factores de riesgo asociados. PMID:21315667

Learning of Unknown Environments in Goal-Directed Guidance and Navigation Tasks: Autonomous Systems and Humans

NASA Astrophysics Data System (ADS)

Vidal, Joao Vasco Silvestres

Este trabalho expoe um estudo teorico e experimental das propriedades anisotropicas magnetoeletricas (ME) em diferentes compositos contendo monocristais piezoeletricos (PE), maioritariamente sem chumbo na sua composicao, com vista a diversas aplicacoes multifuncionais. Uma descricao linear do efeito ME em termos de campos eletricos, magneticos e elasticos e constantes materiais e apresentada. Um modelo fenomenologico quasi-estatico e usado para ilustrar a relacao entre as constantes materiais, sua anisotropia e os coeficientes MEs transversais de tensao e carga. Subsequentemente, este modelo e empregue para estimar o maximo coeficiente ME direto de tensao expectavel numa serie de compositos tri-camadas de Metglas/Piezocristal/Metglas em funcao da orientacao do cristal PE. Demonstra-se assim como os efeitos MEs sao fortemente dependentes da orientacao cristalina, o que suporta a possibilidade de se gerarem coeficientes MEs de tensao elevados em compositos contendo monocristais PEs sem chumbo como o niobato de litio (LiNbO3; LNO), tantalato de litio (LiTaO3), ortofosfato de galio (GaPO4; GPO), quartzo (SiO2), langatato (La3Ga5.5Ta0.5O14) e langasite (La3Ga5SiO14) atraves da otimizacao da orientacao cristalina. Uma tecnica experimental dinâmica de lock-in para a medicao da impedância e efeito ME direto e exposta. O formalismo descritivo desta tecnica, assim como um arranjo experimental desenvolvido para o efeito sao apresentados. O esquema e caracteristicas deste, assim como diferentes formas de reduzir o ruido e a indesejavel inducao mutua sao exploradas. Um estudo comparativo do efeito ME direto em compositos tri-camadas de Metglas e monocristais de LNO e PMN-PT conectados de forma simples e exposto. Embora o PMN-PT possua piezocoeficientes de carga muito superiores aos do LNO, o coeficiente ME direto de tensao demonstrou-se comparavel entre ambos os compositos devido a uma muito menor permitividade dieletrica do LNO. Calculos teoricos indicam ainda que as propriedades MEs poderao ser significativamente melhoradas (ate 500 V/(cm.Oe)) atraves da otimizacao do ângulo de corte do LNO, espessura relativa entre camadas ferroeletrica/ferromagnetica e uma melhor colagem entre o Metglas e o LNO. Vantagens da utilizacao do material ferroeletrico LNO em compositos MEs sao discutidas. Num estudo subsequente, as propriedades dinâmicas anisotropicas de impedância e MEs em compositos tri-camadas de Metglas e monocristais PEs sem chumbo de LNO e GPO sao exploradas. Medicoes foram realizadas em funcao do corte de cristal, magnitude e orientacao do campo magnetico de polarizacao e frequencia do campo de modulacao. Coeficientes MEs altamente intensos em certos modos de ressonância sao explorados, e a sua relacao com as propriedades materiais dos cristais e geometria dos compositos e investigada. Um coeficiente ME de ate 249 V/(cm.Oe) foi aqui observado num composito com um cristal de LNO com corte 41ºY a 323.1 kHz. Mostramos assim que compositos multicamadas contendo cristais sem chumbo de LNO e GPO podem exibir efeitos MEs anisotropicos relativamente elevados. Demonstramos tambem que o controlo da orientacao dos cristais PEs pode em principio ser usado na obtencao de propriedades MEs anisotropicas desejaveis para qualquer aplicacao. Caracteristicas unicas como elevada estabilidade quimica, piezoeletricidade linear e robusteza termica abrem verdadeiras perspetivas para a utilizacao de compositos baseados no LNO e GPO em diversas aplicacoes. Eventualmente, compositos bi-camadas contendo lâminas PEs com bidominios de LNO com corte 127ºY foram estudados tanto teoricamente como experimentalmente. Estas lâminas de LNO possuem uma estrutura de bidominios com vetores de polarizacao espontânea opostos ao longo da direcao da sua espessura (i.e. uma estrutura de macrodominios ferroeletricos "head-to-head" ou "tail-to-tail") Medicoes de impedância, efeito ME e densidade de ruido magnetico equivalente foram realizadas nos compositos operando sob condicoes quasi-estaticas e de ressonância. Coeficientes MEs de ate 578 V/(cm.Oe) foram obtidos a ca. 30 kHz sob ressonâncias de dobramento usando cristais PEs com 0.5 mm de espessura. Medicoes de densidade de ruido magnetico equivalente demosntraram valores de ate 153 pT/Hz1/2 a 1 kHz (modo quasi-estatico) e 524 fT/Hz1/2 sob condicoes de ressonância. E de esperar que uma otimizacao adicional das tecnicas de fabrico, geometria dos compositos e circuitos de detencao possa permitir reduzir estes valores ate pelo menos 10 pT/Hz1/2 e 250 fT/Hz1/2, respetivamente, e a frequencia de ressonância em pelo menos duas ordens de grandeza. Estes sistemas poderao assim no futuro ser usados em sensores vetoriais de campo magnetico simples e sensiveis, passivos e estaveis e operaveis a elevadas temperaturas. None

Transcorneal iontophoresis of dendrimers: PAMAM corneal penetration and dexamethasone delivery.

PubMed

Souza, Joel G; Dias, Karina; Silva, Silas A M; de Rezende, Lucas C D; Rocha, Eduardo M; Emery, Flavio S; Lopez, Renata F V

2015-02-28

Iontophoresis of nanocarriers in the eye has been proposed to sustain drug delivery and maintain therapeutic concentrations. Fourth generation polyamidoamine (PAMAM) dendrimers are semi-rigid nanoparticles with surface groups that are easily modified. These dendrimers are known to modulate tight junctions, increase paracellular transport of small molecules and be translocated across epithelial barriers, exhibiting high uptake by different cell lines. The first aim of this study was to investigate the effect of iontophoresis on PAMAM penetration and distribution into the cornea. The second aim was to evaluate, ex vivo and in vivo, the effect of these dendrimers in dexamethasone (Dex) transcorneal iontophoresis. Anionic (PAMAM G3.5) and cationic (PAMAM G4) dendrimers were labeled with fluorescein isothiocyanate (FITC), and their distribution in the cornea was investigated using confocal microscopy after ex vivo anodal and cathodal iontophoresis for various application times. The particle size distribution and zeta potential of the dendrimers in an isosmotic solution were determined using dynamic light scattering and Nanoparticle Tracking Analysis (NTA), where the movement of small particles and the formation of large aggregates, from 5 to 100 nm, could be observed. Transcorneal iontophoresis increased the intensity and depth of PAMAM-FITC fluorescence in the cornea, suggesting improved transport of the dendrimers across the epithelium toward the stroma. PAMAM complexes with Dex were characterized by (13)C-NMR, (1)H-NMR and DOSY. PAMAM G3.5 and PAMAM G4 increased the aqueous solubility of Dex by 10.3 and 3.9-fold, respectively; however, the particle size distribution and zeta potential remained unchanged. PAMAM G3.5 decreased the Dex diffusion coefficient 48-fold compared with PAMAM G4. The ex vivo studies showed that iontophoresis increased the amount of Dex that penetrated into the cornea by 2.9, 5.6 and 3.0-fold for Dex, Dex-PAMAM G4 and Dex-PAMAM G3.5, respectively. In vivo experiments, however, revealed that iontophoresis of Dex-PAMAM-G3.5 increased Dex concentration in the aqueous humor by 6.6-fold, while iontophoresis of Dex-PAMAM G4 and Dex increased it 2.5 and 2-fold, respectively. Therefore, iontophoresis targeted PAMAM to the cornea but it is the sustained delivery of the Dex from PAMAM that prevents its rapid elimination from the aqueous humor. In conclusion, iontophoresis of PAMAM complexes represents a promising strategy for targeted and sustained topical drug delivery to the eye. Copyright © 2015 Elsevier B.V. All rights reserved.

[Kombinierte Anwendung von Strahlentherapie und adjuvanter Therapie mit einem Mistelextrakt (Viscum album L.) zur Behandlung des oralen malignen Melanoms beim Hund: Eine retrospektive Studie].

PubMed

von Bodungen, Uta; Ruess, Katja; Reif, Marcus; Biegel, Ulrike

2017-01-01

Hintergrund: Orale maligne Melanome (OMM) des Hundes zeichnen sich durch schnelles Wachstum, lokale Invasion und hohe Metastasierungsraten aus. Extrakte auf Basis von Viscum album L. (VAE) werden zunehmend in der Krebstherapie sowohl in der Human- als auch in der Veterinärmedizin eingesetzt. Ziel unserer Studie war es zu untersuchen, inwieweit die adjuvante Therapie mit VAE eine therapeutische Option zur Behandlung von OMM ist. Besonderes Augenmerk galt dabei der Überlebenszeit und möglichen Nebenwirkungen. Tiere und Methoden: 26 Hunde mit OMM, die in einem der größten veterinäronkologischen Zentren der Schweiz allesamt eine Strahlentherapie erhielten (teilweise nach operativer Tumorresektion) wurden in die retrospektive Studie eingeschlossen: 18 Hunde wurden mit VAE behandelt (1 ml VAE (Iscador®) in ansteigenden Konzentrationen von 0,1 bis 20 mg/ml subkutan 3-mal pro Woche (VAE-Gruppe), 8 erhielten keine adjuvante Behandlung (Vergleichsgruppe). Wir verglichen die Größenentwicklung der OMM sowie die Überlebenszeit. Ergebnisse: Patienten mit Bestrahlung und adjuvanter VAE-Therapie zeigten mit 236 Tagen eine signifikant längere mediane Überlebenszeit im Vergleich zu Patienten mit Bestrahlung, aber ohne adjuvante VAE-Therapie (49 Tage; Log-Rank-Test: p = 0,0047). Die VAE-Therapie verlängerte die Überlebenszeit um mehr als zwei Drittel (Hazard Ratio (HR) = 0,30, 95%-Konfidenzintervall (KI) 0,11-0,86; p = 0,024), während ein höheres Tumorstadium gemäß UICC (Union internationale contre le cancer) einen statistischen Trend zur Verdopplung des Sterberisikos zeigte (UICC-Stadium III/IV vs. I/II: HR = 2,12, 95%-KI 0,88-5,12; p = 0,095). Zwei Patienten zeigten milde Nebenwirkungen während der VAE-Behandlung. Einer der beiden zeigte 1 Tag lang ein selbstlimitiertes Fieber, bei dem anderen Patienten reduzierten wir die Dosis von einem konzentrierteren zu einem weniger konzentrierten VAE (Serie 0) aufgrund von Müdigkeit, die daraufhin verschwand. Schlussfolgerungen: VAE ist eine sichere, nebenwirkungsarme Behandlung und scheint sich positiv auf die Überlebenszeit von Hunden mit OMM auszuwirken. Somit ist dieser therapeutische Ansatz es wert, vermehrt bei der adjuvant zur Strahlentherapie eingesetzten Behandlung des OMM in Betracht gezogen zu werden. Die verglichenen Gruppen waren jedoch klein, divers und nicht konsistent hinsichtlich aller prognostischen Parameter. Eine prospektive Studie mit einer größeren Studienpopulation wäre daher von Interesse. © 2017 S. Karger GmbH, Freiburg.

Determination of nuclear tracks parameters on sequentially etched PADC detectors

NASA Astrophysics Data System (ADS)

Horwacik, Tomasz; Bilski, Pawel; Koerner, Christine; Facius, Rainer; Berger, Thomas; Nowak, Tomasz; Reitz, Guenther; Olko, Pawel

Polyallyl Diglycol Carbonate (PADC) detectors find many applications in radiation protection. One of them is the cosmic radiation dosimetry, where PADC detectors measure the linear energy transfer (LET) spectra of charged particles (from protons to heavy ions), supplementing TLD detectors in the role of passive dosemeter. Calibration exposures to ions of known LET are required to establish a relation between parameters of track observed on the detector and LET of particle creating this track. PADC TASTRAK nuclear track detectors were exposed to 12 C and 56 Fe ions of LET in H2 O between 10 and 544 keV/µm. The exposures took place at the Heavy Ion Medical Accelerator (HIMAC) in Chiba, Japan in the frame of the HIMAC research project "Space Radiation Dosimetry-Ground Based Verification of the MATROSHKA Facility" (20P-240). Detectors were etched in water solution of NaOH with three different temperatures and for various etching times to observe the appearance of etched tracks, the evolution of their parameters and the stability of the etching process. The applied etching times (and the solution's concentrations and temperatures) were: 48, 72, 96, 120 hours (6.25 N NaOH, 50 O C), 20, 40, 60, 80 hours (6.25 N NaOH, 60 O C) and 8, 12, 16, 20 hours (7N NaOH, 70 O C). The analysis of the detectors involved planimetric (2D) measurements of tracks' entrance ellipses and mechanical measurements of bulk layer thickness. Further track parameters, like angle of incidence, track length and etch rate ratio were then calculated. For certain tracks, results of planimetric measurements and calculations were also compared with results of optical track profile (3D) measurements, where not only the track's entrance ellipse but also the location of the track's tip could be directly measured. All these measurements have been performed with the 2D/3D measurement system at DLR. The collected data allow to create sets of V(LET in H2 O) calibration curves suitable for short, intermediate and long etching time and will be use during analysis of detectors exposed on the International Space Station during DOSIS and MATROSHKA experiments. The help and support of Yukio Uchihori and Hisashi Kitamura during the irradiations at HIMAC is highly appreciated. This work was supported by the Polish Ministry of Science and Higher Education, grants: No N N505 261535 and No. DWM/N118/ESA/2008.

Reactivity and O2 Formation by Mn(IV)- and Mn(V)-Hydroxo Species Stabilized within a Polyfluoroxometalate Framework.

PubMed

Schreiber, Roy E; Cohen, Hagai; Leitus, Gregory; Wolf, Sharon G; Zhou, Ang; Que, Lawrence; Neumann, Ronny

2015-07-15

Manganese(IV,V)-hydroxo and oxo complexes are often implicated in both catalytic oxygenation and water oxidation reactions. Much of the research in this area is designed to structurally and/or functionally mimic enzymes. On the other hand, the tendency of such mimics to decompose under strong oxidizing conditions makes the use of molecular inorganic oxide clusters an enticing alternative for practical applications. In this context it is important to understand the reactivity of conceivable reactive intermediates in such an oxide-based chemical environment. Herein, a polyfluoroxometalate (PFOM) monosubstituted with manganese, [NaH2(Mn-L)W17F6O55](q-), has allowed the isolation of a series of compounds, Mn(II, III, IV and V), within the PFOM framework. Magnetic susceptibility measurements show that all the compounds are high spin. XPS and XANES measurements confirmed the assigned oxidation states. EXAFS measurements indicate that Mn(II)PFOM and Mn(III)PFOM have terminal aqua ligands and Mn(V)PFOM has a terminal hydroxo ligand. The data are more ambiguous for Mn(IV)PFOM where both terminal aqua and hydroxo ligands can be rationalized, but the reactivity observed more likely supports a formulation of Mn(IV)PFOM as having a terminal hydroxo ligand. Reactivity studies in water showed unexpectedly that both Mn(IV)-OH-PFOM and Mn(V)-OH-PFOM are very poor oxygen-atom donors; however, both are highly reactive in electron transfer oxidations such as the oxidation of 3-mercaptopropionic acid to the corresponding disulfide. The Mn(IV)-OH-PFOM compound reacted in water to form O2, while Mn(V)-OH-PFOM was surprisingly indefinitely stable. It was observed that addition of alkali cations (K(+), Rb(+), and Cs(+)) led to the aggregation of Mn(IV)-OH-PFOM as analyzed by electron microscopy and DOSY NMR, while addition of Li(+) and Na(+) did not lead to aggregates. Aggregation leads to a lowering of the entropic barrier of the reaction without changing the free energy barrier. The observation that O2 formation is fastest in the presence of Cs(+) and ∼fourth order in Mn(IV)-OH-PFOM supports a notion of a tetramolecular Mn(IV)-hydroxo intermediate that is viable for O2 formation in an oxide-based chemical environment. A bimolecular reaction mechanism involving a Mn(IV)-hydroxo based intermediate appears to be slower for O2 formation.

Global Analysis of Anthropogenic Debris Ingestion by Sea Turtles

PubMed Central

Schuyler, Qamar; Hardesty, Britta Denise; Wilcox, Chris; Townsend, Kathy

2014-01-01

Ingestion of marine debris can have lethal and sublethal effects on sea turtles and other wildlife. Although researchers have reported on ingestion of anthropogenic debris by marine turtles and implied incidences of debris ingestion have increased over time, there has not been a global synthesis of the phenomenon since 1985. Thus, we analyzed 37 studies published from 1985 to 2012 that report on data collected from before 1900 through 2011. Specifically, we investigated whether ingestion prevalence has changed over time, what types of debris are most commonly ingested, the geographic distribution of debris ingestion by marine turtles relative to global debris distribution, and which species and life-history stages are most likely to ingest debris. The probability of green (Chelonia mydas) and leatherback turtles (Dermochelys coriacea) ingesting debris increased significantly over time, and plastic was the most commonly ingested debris. Turtles in nearly all regions studied ingest debris, but the probability of ingestion was not related to modeled debris densities. Furthermore, smaller, oceanic-stage turtles were more likely to ingest debris than coastal foragers, whereas carnivorous species were less likely to ingest debris than herbivores or gelatinovores. Our results indicate oceanic leatherback turtles and green turtles are at the greatest risk of both lethal and sublethal effects from ingested marine debris. To reduce this risk, anthropogenic debris must be managed at a global level. Análisis Global de la Ingesta de Residuos Antropogénicos por Tortugas Marinas La ingesta de residuos marinos puede tener efectos letales y subletales sobre las tortugas marinas y otros animales. Aunque hay investigadores que han reportado la ingesta de residuos antropogénicos por tortugas marinas y la incidencia de la ingesta de residuos ha incrementado con el tiempo, no ha habido una síntesis global del fenómeno desde 1985. Por esto analizamos 37 estudios publicados, desde 1985 hasta 2012, que reportan datos colectados desde antes de 1900 y a lo largo del 2011. Investigamos específicamente si el predominio de la ingesta ha cambiado con el tiempo, qué tipos de residuos se ingieren comúnmente, la distribución geográfica de la ingesta de residuos por tortugas marinas en relación a la distribución global de residuos y cuáles especies y etapas de vida tienen más probabilidad de ingerir residuos. La probabilidad de que las tortugas verdes (Chelonia mydas) y laúd (Dermochelys coriacea) ingieran escombros incrementa significativamente con el tiempo; plástico fue el residuo que más se ingirió. Las tortugas en casi todas las regiones estudiadas ingieren residuos, pero la probabilidad de ingesta no estuvo relacionada con las densidades modeladas de residuos. Además de esto, tortugas más pequeñas, en etapa oceánica de vida, tuvieron una mayor probabilidad de ingerir residuos que las tortugas forrajeras terrestres, mientras que las especies carnívoras tuvieron menos probabilidad de ingerir residuos que las herbívoras o las gelatinívoras. Nuestros resultados indican que las tortugas verdes y laúd tienen el mayor riesgo de efectos letales y subletales de la ingesta de residuos marinos. Para reducir el riesgo, los residuos antropogénicos deben manejarse en un nivel global. PMID:23914794

Development and validation of educational technology for venous ulcer care.

PubMed

Benevides, Jéssica Lima; Coutinho, Janaina Fonseca Victor; Pascoal, Liliane Chagas; Joventino, Emanuella Silva; Martins, Mariana Cavalcante; Gubert, Fabiane do Amaral; Alves, Allana Mirella

2016-04-01

To develop and validate an educational technology venous ulcers care. Methodological study conducted in five steps: Situational diagnosis; literature review; development of texts, illustrations and layout; apparent and content validity by the Content Validity Index, assessment of Flesch Readability Index; and pilot testing. The developed technology was a type of booklet entitled Booklet for Venous Ulcers Care, consisting of seven topics: Diet and food intake, walking and light exercise, resting with elevated leg, bandage care, compression therapy, family support, and keeping healthy habits. The apparent validity revealed minimal agreement of 85.7% in the clarity and comprehensibility. The total content validity index was 0.97, the Flesch Readability Index was 75%, corresponding to the reading "fairly easy". The pilot test showed that 100% of people with venous ulcers evaluated the text and the illustrations as understandable, as appropriate. The educational technology proved to be valid for the appearance and content with potential for use in clinical practice. Construir e validar uma tecnologia educativa para cuidados com úlcera venosa. Estudo metodológico realizado em cinco fases: diagnóstico situacional; revisão da literatura; desenvolvimento de textos, ilustrações e diagramação; validade de aparência e de conteúdo pelo Índice de Validade de Conteúdo, avaliação do Índice de Legibilidade de Flesch; e teste piloto. A tecnologia desenvolvida foi do tipo cartilha intitulada Cartilha para cuidados com úlcera venosa, constituída de sete tópicos: Alimentação, Caminhadas e exercícios leves, Repouso com a perna elevada, Cuidados com o curativo, Terapia compressiva, Apoio familiar, e manter hábitos saudáveis. A validade aparente revelou concordância mínima de 85,7% na clareza e compreensibilidade. O Índice de Validade de Conteúdo total foi de 0,97, o Índice de legibilidade de Flesch foi de 75%, o que correspondeu à leitura "razoavelmente fácil". O teste piloto revelou que 100% das pessoas com úlcera venosa avaliaram o texto como compreensivo e as ilustrações, como adequadas. A tecnologia educativa mostrou-se válida quanto à aparência e ao conteúdo, com potencial de utilização na prática clínica.

Incidence and factors related to delirium in an intensive care unit.

PubMed

Mori, Satomi; Takeda, Juliana Rumy Tsuchihashi; Carrara, Fernanda Souza Angotti; Cohrs, Cibelli Rizzo; Zanei, Suely Sueko Viski; Whitaker, Iveth Yamaguchi

2016-01-01

To identify the incidence of delirium, compare the demographic and clinical characteristics of patients with and without delirium, and verify factors related to delirium in critical care patients. Prospective cohort with a sample made up of patients hospitalized in the Intensive Care Unit (ICU) of a university hospital. Demographic, clinical variables and evaluation with the Confusion Assessment Method for Intensive Care Unit to identify delirium were processed to the univariate analysis and logistic regression to identify factors related to the occurrence of delirium. Of the total 149 patients in the sample, 69 (46.3%) presented delirium during ICU stay, whose mean age, severity of illness and length of ICU stay were statistically higher. The factors related to delirium were: age, midazolam, morphine and propofol. Results showed high incidence of ICU delirium associated with older age, use of sedatives and analgesics, emphasizing the need for relevant nursing care to prevent and identify early, patients presenting these characteristics. Identificar a incidência de delirium, comparar as características demográficas e clínicas dos pacientes com e sem delirium e verificar os fatores relacionados ao delirium em pacientes internados em Unidade de Terapia Intensiva (UTI). Coorte prospectiva, cuja amostra foi constituída de pacientes internados em UTI de um hospital universitário. Variáveis demográficas, clínicas e da avaliação com o Confusion Assessment Method for Intensive Care Unit para identificação de delirium foram processadas para análise univariada, e regressão logística para identificar fatores relacionados à ocorrência do delirium. Do total de 149 pacientes da amostra, 69 (46,3%) apresentaram delirium durante a internação na UTI, observando-se que a média da idade, o índice de gravidade e o tempo de permanência nas UTI foram estatisticamente maiores. Os fatores relacionados ao delirium foram: idade, midazolam, morfina e propofol. Os resultados mostraram elevada incidência de delirium na UTI e sua ocorrência associada às idades mais avançadas e o uso de sedativos e analgésicos, ressaltando-se a importância da atuação do enfermeiro na prevenção e identificação precoce do quadro nos pacientes com essas características.

Development of lithium disilicate based glass-ceramics =

NASA Astrophysics Data System (ADS)

Fernandes, Hugo Alexandre Goncalves da Rocha

O principal objectivo deste estudo foi o desenvolvimento de vitroceramicos a base de dissilicato de litio no sistema Li2O-K2O-Al2O3-SiO2 contendo uma razao molar SiO2/Li2O muito afastada da do dissilicato de litio (Li2Si2O5) usando composicoes simples e a tecnica tradicional de fusao-vazamento de vidro de forma a obter materiais com propriedades mecanicas, termicas, quimicas e electricas superiores que permitam a utilizacao destes materiais em diversas aplicacoes funcionais. Investigou-se o fenomeno de separacao de fases, a cristalizacao e as relacoes estrutura-propriedades de vidros nos sistemas Li2O-SiO2, Li2O-Al2O3-SiO2 e Li2O-K2O-Al2O3-SiO2. Os vidros nos sistemas Li2O-SiO2 e Li2O-Al2O3-SiO2 apresentaram fraca densificacao e resultaram em materiais frageis, contrastando com a boa sinterizacao dos vidros no sistema Li2O-K2O-Al2O3-SiO2. Pequenas adicoes de Al2O3 e K2O ao sistema Li2O-SiO2 permitiram controlar a separacao de fases devido a formacao de especies de Al(IV) que confirmaram o papel de Al2O3 como formador de rede. Os compactos de po de vidro das composicoes contendo Al2O3 e K2O tratados termicamente resultaram em vitroceramicos bem densificados, apresentando dissilicato de litio como a principal fase cristalina, e valores de resistencia mecanica a flexao, resistencia quimica e condutividade electrica (173-224 MPa, 25-50 mg/cm2 e 2´10-18 S/cm, respectivamente) que possibilitam a utilizacao destes materiais em diversas aplicacoes funcionais. A adicao de P2O5, TiO2 e ZrO2 ao sistema Li2O-K2O-Al2O3-SiO2 como agentes nucleantes revelou que os vidros contendo apresentaram cristalizacao em volume, com a formacao de metassilicato de litio a temperaturas mais baixas e dissilicato de litio para as temperaturas mais elevadas, enquanto a adicao de zirconia reduz o grau de segregacao, aumenta a polimerizacao da matriz vitrea e desloca o valor de Tg para temperaturas superiores, inibindo a cristalizacao.

Cardiac Regeneration using Growth Factors: Advances and Challenges.

PubMed

Rebouças, Juliana de Souza; Santos-Magalhães, Nereide Stela; Formiga, Fabio Rocha

2016-09-01

Myocardial infarction is the most significant manifestation of ischemic heart disease and is associated with high morbidity and mortality. Novel strategies targeting at regenerating the injured myocardium have been investigated, including gene therapy, cell therapy, and the use of growth factors. Growth factor therapy has aroused interest in cardiovascular medicine because of the regeneration mechanisms induced by these biomolecules, including angiogenesis, extracellular matrix remodeling, cardiomyocyte proliferation, stem-cell recruitment, and others. Together, these mechanisms promote myocardial repair and improvement of the cardiac function. This review aims to address the strategic role of growth factor therapy in cardiac regeneration, considering its innovative and multifactorial character in myocardial repair after ischemic injury. Different issues will be discussed, with emphasis on the regeneration mechanisms as a potential therapeutic resource mediated by growth factors, and the challenges to make these proteins therapeutically viable in the field of cardiology and regenerative medicine. Resumo O infarto do miocárdio representa a manifestação mais significativa da cardiopatia isquêmica e está associado a elevada morbimortalidade. Novas estratégias vêm sendo investigadas com o intuito de regenerar o miocárdio lesionado, incluindo a terapia gênica, a terapia celular e a utilização de fatores de crescimento. A terapia com fatores de crescimento despertou interesse em medicina cardiovascular, devido aos mecanismos de regeneração induzidos por essas biomoléculas, incluindo angiogênese, remodelamento da matriz extracelular, proliferação de cardiomiócitos e recrutamento de células-tronco, dentre outros. Em conjunto, tais mecanismos promovem a reparação do miocárdio e a melhora da função cardíaca. Esta revisão pretende abordar o papel estratégico da terapia, com fatores de crescimento, para a regeneração cardíaca, considerando seu caráter inovador e multifatorial sobre o reparo do miocárdio após dano isquêmico. Diferentes questões serão discutidas, destacando-se os mecanismos de regeneração como recurso terapêutico potencial mediado por fatores de crescimento e os desafios para tornar essas proteínas terapeuticamente viáveis no âmbito da cardiologia e da medicina regenerativa.

[Not Available].

PubMed

De Abajo Larriba, Ana Beatriz; Díaz Rodríguez, Ángel; González-Gallego, Javier; Méndez Rodríguez, Enrique; Álvarez Álvarez, María Jesús; Capón Álvarez, Jessica; Peleteiro Cobo, Beatriz; Mahmoud Atoui, Omar; De Abajo Olea, Serafín; Martínez de Mandojana Hernández, Juan

2016-07-19

Introducción: estimar la prevalencia del tabaquismo y analizar cómo se diagnostican y se trata a los fumadores diagnosticados de EPOC.Métodos: estudio epidemiológico, transversal, multicéntrico (30 centros salud de la provincia de León). Incluyó pacientes mayores de 35 años diagnosticados y tratados de EPOC. Variables analizadas: edad, sexo, hábitat, datos antropométricos, tabaquismo, número de paquetes/año, cooximetría, dependencia (escala analógico-visual), motivación (test de Fagerström), autoeficacia, estado anímico, intentos previos, terapia cognitivo-conductual, tratamiento farmacológico (TSN, bupropión, vareniclina) y recaídas. Los resultados se expresan con sus IC al 95,5%.Resultados: se incluyó a 833 pacientes, el 85,8% varones, edad media: 64,69 (53,66-75,61) años y 20,65 (4,47-36,8) años de evolución de la EPOC. El 86,67% (80,30-93,30) tenían antecedentes de tabaquismo (n = 722), de 35,26 (17,87-52,64) años de evolución, con consumo medio 28,36 (9,60-46,86) paquetes año, p < 0,001, siendo el 58% fumadores severos. El 57,4% (53,90-60,60) son exfumadores. El 29,3% (26,40-32,70) fumadores activos declarados vs. 35,11% (33,90-37,12) fumadores diagnosticados por cooximetría p < 0,05. Los 288 fumadores activos, presentaban baja motivación (49,80%), alta dependencia (49,5%), actitud negativa (52,60%), bajo estado de ánimo (32,05%), con 2,72 (1,74-3,67) intentos para dejar de fumar, p < 0,0001. La terapia conductivo-conductual (TCC) combinado con tratamiento farmacológico se realizó en el 55,8% (52,2-54,9), p < 0,05; La intervención más efectiva fue TCC combinada con vareniclina logrando una abstinencia del 29,86%. En total dejaron de fumar un 51,05% (49,49-52,70) de los pacientes con EPOC, p < 0,001.Conclusiones: la prevalencia de tabaquismo en la EPOC en nuestro medio continúa siendo inadmisiblemente elevada. Es necesaria una mayor implicación para disminuir su impacto en la salud de estos pacientes.

Acute tubulointerstitial nephritis with severe renal impairment associated with multisystem IgG4-related disease.

PubMed

Beltrame, Rafael Coimbra Ferreira; Friderichs, Maurício; Fior, Bárbara Rayanne; Schaefer, Pedro Guilherme; Thomé, Gustavo Gomes; Silva, Dirceu Reis da; Barros, Elvino José Guardão; Seligman, Renato; Veronese, Francisco Veríssimo

2016-01-01

The IgG4-related disease has a wide clinical spectrum where multiple organs can be affected, and the diagnosis depends on typical histopathological findings and an elevated IgG4 expression in plasma cells in the affected tissue. We describe the clinical presentation and evolution of a patient with acute tubulointerstitial nephritis, severe kidney failure and systemic manifestations such as lymphadenomegaly and chronic pancreatitis. The diagnosis was confirmed by the clinical picture and kidney and lymph node histopathology, in which immunohistochemistry of the lymphoid tissue showed policlonality and increased expression of IgG4, with a IgG4/total IgG ratio > 80%. The patient was treated with prednisone at a dose of 60 mg/day, followed by mycophenolate mofetil, and showed clinical and renal function improvement at 6 months of follow-up. The high index of suspicion of IgG4-related disease with multisystem involvement and the early treatment of this condition are essential to improve the prognosis of affected patients. Resumo A doença relacionada à IgG4 tem um espectro clínico amplo em que múltiplos órgãos podem ser afetados, e o diagnóstico depende de achados histopatológicos típicos e elevada expressão de IgG4 em plasmócitos no tecido afetado. Descrevemos o quadro clínico e a evolução de um paciente com nefrite túbulo-intersticial aguda, insuficiência renal grave e manifestações sistêmicas como linfoadenomegalias e pancreatite crônica. O diagnóstico foi confirmado pelas características clínicas e pela histopatologia renal e de linfonodo, na qual a imunohistoquímica mostrou tecido linfoide com policlonalidade e expressão aumentada de IgG4, com uma relação IgG4/IgG total > 80%. O paciente foi tratado com prednisona na dose de 60 mg/dia, seguido de micofenolato mofetil, e apresentou melhora clínica e da função renal depois de 6 meses de tratamento. O alto índice de suspeição da doença relacionada ao IgG4 com comprometimento multissistêmico e o tratamento precoce desta condição são primordiais para a melhora do prognóstico destes pacientes.

The Role of Sex and Mating Status in the Expansion Process of Arhopalus rusticus (Coleoptera: Cerambycidae)-an Exotic Cerambycid in Argentina.

PubMed

Grilli, Mariano Pablo; Fachinetti, Romina

2017-06-01

In Córdoba province, central Argentina, there is an area of introduced pine trees, in which an invading Cerambycid, Arhopalus rusticus (L.), was detected in this region for the first time in 2006. The species has since expanded its range until it now occupies the whole area. Arhopalus rusticus is a common species in pine forests of the northern hemisphere. In this paper, we analyze how sex and mating status affects flight performance and the potential distribution of this species. The study was performed with individuals collected from introduced pine forests in the center-west of Córdoba Province (Argentina). The dispersal capability of A. rusticus was determined by measuring flight speed and distance traveled by recently emerged mated and unmated A. rusticus in flight mills. Data of preflight body weight, postflight body weight, body length, and elytron size were obtained from the individuals that were flown in the flight mill. We found that females had a greater body length, weighed more, had longer elytra, and were stronger flyers than males. We also found that mated individuals flew faster and longer distances than unmated individuals, and consumed a smaller fraction of their body weight. A positive ratio was observed between elytra size and flight speed. A map of males' and females' dispersal distances was produced for the study region, using the adjusted dispersal distance distribution of males and females. The flight performance showed that, as females disperse after copulation, they increase the chances of establishing the species in unoccupied areas.En la provincia de Córdoba, Argentina, hay una importante área de pinos implantados. En esta región durante el año 2006 se detectó por primera vez a Arhopalus rusticus (L.), un Cerambycidae invasor. A. rusticus es una especie común en los bosques de pino del hemisferio norte. En este trabajo analizamos de qué manera el sexo y el estado de apareamiento afectan el desempeño de vuelo y la distribución potencial de esta especie. Utilizamos individuos recolectados de los bosques de pino implantados en la región centro oeste de la provincia de Córdoba (Argentina). La capacidad de dispersión de Arhopalus rusticus se determinó haciendo volar individuos recién emergidos en un molino de vuelo. Se registró el peso previo y posterior al vuelo, el largo del cuerpo y el tamaño del élitro. Las hembras fueron mejores voladoras, más largas, más pesadas, con élitros más largos que los machos. Observamos diferencias entre el potencial de dispersión dependiendo del estado de apareamiento de los individuos. Los individuos apareados volaron más rápido y mayores distancias que los individuos no apareados y consumieron una menor fracción de su peso corporal. Se observó una relación positiva entre el tamaño del élitro y la velocidad de vuelo. Se generó un mapa de las distancias de dispersión potencial de los machos y de las hembras para la región de estudio utilizando las distribuciones de las distancias obtenidas del molino de vuelo. La dispersión post copulación incrementa las chances de que la especie se establezca en zonas no ocupadas. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Diffusion of a Highly-Charged Supramolecular Assembly: Direct Observation of Ion-Association in Water

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

University of California, Berkeley; Lawrence Berkeley National Laboratory; Raymond, Kenneth

2007-10-22

Understanding the solution behavior of supramolecular assemblies is essential for a full understanding of the formation and chemistry of synthetic host-guest systems. While the interaction between host and guest molecules is generally the focus of mechanistic studies of host-guest complexes, the interaction of the host-guest complex with other species in solution remains largely unknown, although in principle accessible by diffusion studies. Several NMR techniques are available to monitor diffusion and have recently been reviewed. Pulsed gradient spin-echo (PGSE) NMR methods have attracted increasing interest, since they allow diffusion coefficients to be measured with high accuracy; they have been successfully usedmore » with observation of {sup 7}Li and {sup 31}P nuclei as well as with {sup 1}H NMR. We report here the direct measurement of diffusion coefficients to observe ion-association interactions by counter cations with a highly-charged supramolecular assembly. Raymond and coworkers have described the design and chemistry of a class of metal-ligand supramolecular assemblies over the past decade. The [Ga{sub 4}L{sub 6}]{sup 12-} (L = 1,5-bis(2,3-dihydroxybenzamido)naphthalene) (1) (Figure 1) assembly has garnered the most attention, with the exploration of the dynamics and mechanism of guest exchange as well as the ability of 1 to achieve either stoichiometric or catalytic reactions inside its interior cavity. Recent studies have revealed the importance of counter cations in solution on the chemistry of 1. During the mechanistic study of the C-H bond activation of aldehydes by [Cp*Ir(PMe{sub 3})(olefin){sup +} {contained_in} 1]{sup 11-} a stepwise guest dissociation mechanism with an ion-paired intermediate was proposed. Similarly, in the mechanism for the hydrolysis of iminium cations generated from the 3-aza Cope rearrangement of enammonium cations in 1, the presence of an exterior ion association was part of the kinetic model. To further substantiate the indirect kinetic evidence for such ion-paired species, we sought to explore the solution behavior of 1 by studying the diffusion of 1 with varying alkali and tetraalkyl ammonium cations. For large molecules in solution, such as synthetic supramolecular assemblies, the diffusion behavior of host and guest molecules can provide valuable information on host-guest interaction. One characteristic feature of a stable host-guest complex is that the host and guest molecules diffuse at the same rate in solution; this has been observed in a number of supramolecular systems. In order to confirm that this system was suitable for study by diffusion NMR spectroscopy, a PGSE-DOSY spectrum was acquired of [NEt{sub 4} {contained_in} 1]{sup 11-} (Figure 2), which shows that the host and guest molecules diffuse at the same rate. Quantitative analysis of the data, from monitoring the integral of host and guest resonances as a function of applied gradient strength, gave identical diffusion coefficients, confirming that the host and guest molecules diffuse together.« less

Burnout Syndrome prevalence of on-call surgeons in a trauma reference hospital and its correlation with weekly workload: cross-sectional study.

PubMed

Novais, Rodrigo Nobre DE; Rocha, Louise Matos; Eloi, Raissa Jardelino; Santos, Luciano Menezes Dos; Ribeiro, Marina Viegas Moura Rezende; Ramos, Fernando Wagner DA Silva; Lima, Fernando José Camello DE; Sousa-Rodrigues, Célio Fernando DE; Barbosa, Fabiano Timbó

2016-01-01

to determine the prevalence of Burnout Syndrome (BS) for surgeons working in referral hospital for trauma in Maceio and to evaluate the possible correlation between BS and weekly workload. cross-sectional study with 43 on-call surgeons at Professor Osvaldo Brandão Vilela General State Hospital, Maceió, between July and December, 2015. A self-administered form was used to evaluate BS through the Maslach Burnout Inventory (MBI) and socio-demographic characteristics among participants. Spearman's S test was used to compare BS and weekly workload. Significant level was 5%. among the surgeons studied, 95.35% were male and the mean age was 43.9 ± 8.95 years. The mean weekly workload on call in trauma was 33.90 ± 16.82 hours. The frequency of high scores in at least one of the three dimensions of MBI was 46.5%. Professional achievement was correlated with weekly workload (P = 0.020). the prevalence of Burnout Syndrome among on-call surgeons in referral hospital for trauma was 46.5%. In this sample there was correlation between weekly workload and the Burnout Syndrome. determinar a prevalência da Síndrome de Burnout (SB) em médicos cirurgiões que trabalham em hospital de referência para o trauma em Maceió e avaliar a possível correlação entre SB e a carga horária semanal de trabalho. estudo transversal com 43 cirurgiões de plantão do Hospital Geral do Estado Professor Osvaldo Brandão Vilela, Maceió, entre julho e dezembro de 2015. Um formulário autoadministrado foi utilizado para avaliar SB por meio do Maslach Burnout Inventory (MBI) e as características sociodemográficas entre os participantes. Foi utilizado o teste de Spearman S para comparar SB e carga horária semanal. O nível de significância foi 5%. entre os cirurgiões estudados, 95,35% eram do sexo masculino e a média de idade foi 43,9±8,95 anos. A média da carga horária semanal de plantão no trauma foi 33,90±16,82 horas. A frequência de pontuações elevadas em pelo menos uma das três dimensões do MBI foi 46,5%. Realização profissional foi correlacionada com a carga de trabalho semanal (P=0,020). a prevalência da Síndrome de Burnout entre cirurgiões plantonistas em hospital de referência para o trauma foi 46,5%. Nesta amostra houve correlação entre a carga horária semanal de trabalho e a Síndrome de Burnout.

Indicators of health and safety among institutionalized older adults.

PubMed

Cavalcante, Maria Lígia Silva Nunes; Borges, Cíntia Lira; Moura, Acácia Maria Figueiredo Torres de Melo; Carvalho, Rhanna Emanuela Fontenele Lima de

2016-01-01

To identify the incidence of mortality, diarrheal diseases, scabies and falls; and the prevalence of pressure ulcers - all of which are related to the safety ofinstitutionalized older adults. This was a documentary retrospective study developed in a long-term residential careinstitution for older adults in the Northeast region of Brazil. The data were gathered from records of health assessment indicators filed between January 2008 and December 2015. Analysis included absolute case frequency; the sum of monthly prevalence and incidence rates; mean values of cases; and mean annual incidence and prevalence rates. The incidence of mortality over these nine years ranged from 9% to 13%; of acute diarrheic disease from 13% to 45%; and scabies from 21% to 63%. The prevalence of pressure ulcers ranged from 8% to 23%. Between 2012 and 2015, the incidence rate of falls without injury varied from 38% to 83%, and with injury from12% to 20%. Analysis of the health indicators revealeda high incidence of scabies and falls and a high prevalence of pressure ulcers. The identification of less than optimal rates for performance indicators canhelp improve the quality of nursing care. Identificar a incidência de mortalidade, doenças diarreicas, escabiose e quedas, e a prevalência de lesões por pressão para a segurança do idoso institucionalizado. Estudo documental, retrospectivo desenvolvido em uma Instituição de Longa Permanência para Idosos, localizada no nordeste do Brasil. Os dados foram coletados por meio dos registros dos indicadores de avaliação de saúde, arquivados de janeiro de 2008 a dezembro de 2015. A análise incluiu a frequência absoluta dos casos; o somatório das taxas de prevalência e incidência mensais; a média de casos e das taxas de incidência e prevalência anuais. Observa-se que a incidência de óbitos nos nove anos considerados variou de 9 a 13%; de doenças diarreicas agudas, de 13 a 45%; e de escabiose, de 21 a 63%. A prevalência de lesão por pressão oscilou de 8 a 23%. Entre os anos de 2012 a 2015, a taxa de incidência de quedas sem lesão variou em torno de 38 a 83%, e com lesão, de 12 a 20%. A análise da amplitude dos indicadores de saúde permitiu identificar a alta incidência de escabiose e de quedas e a elevada prevalência de lesões por pressão. A identificação do comprometimento dos indicadores contribui para otimização da qualidade da assistência de enfermagem.

Synthesis of new porphyrinoids for biomedical and materials applications

NASA Astrophysics Data System (ADS)

Stewart, Fraser

The facile synthesis of three non-hydrolysable thioglycosylated porphyrinoids is reported. Starting from meso perfluorophenylporphyrin (TPPF20), the non-hydrolysable thioglycosylated porphyrin (PGlc4), chlorin (CGlc4), isobacteriochlorin (IGlc4), and bacteriochlorin (BGlc4) can be made in 2-3 steps. The ability to append a wide range of targeting agents onto the perfluorophenyl moieties, the chemical stability, and the ability to fine-tune the photophysical properties of the chromophores make this a suitable platform for development of biochemical tags, diagnostics, or as photodynamic therapeutic agents. With reduction of one or two pyrrole double bonds, there is a red shift in the lowest energy absorption band and a significant increase in intensity. The fluorescence of these porphyrinoids is in the order PGlc4 = BGlc4 < CGlc4 < IGlc4 and there is a corresponding decrease in the amount of triplet formed. Fluorescence micrographs of cells after treatment with these four porphyrinoids indicate they are taken up. The CGlc4 and IGlc4 may be dual function agents that can detect cancer by luminescence, and treat cancer by photodynamic therapy (PDT). Porphyrins appended with four rigid hydrogen bonding motifs on the meso positions were synthesized and self-assembled into a cofacial cage with four complementary bis- (decyl)melamine units in dry solvents, these hydrogen-bonded cages were analysed by diffusion-ordered spectroscopy (DOSY) in solution. The hydrocarbon chains on the melamine mediate the formation of nanofilms on surfaces as the solvent slowly evaporates. A water soluble zinc (II) phthalocyanine symmetrically appended with eight thioglucose units was synthesized from commercially available hexadecafluoro-phthalocyaninato zinc(II) by controlled nucleophilic substitution of the peripheral fluoro groups by thio-sugars. The photophysical properties and cancer cell uptake studies of this nonhydrolyzable thioglycosylated phthalocyanine are reported. The new compound has amphiphilic character, is chemically and photochemically stable, and can potentially be used as a photosensitizer in photodynamic therapy. A porphyrin bearing pyridyl groups at the meso positions was synthesized using 2,6-diacetamido-4-formylpyridine. A new method has been developed for the synthesis of the precursor aldehyde that avoid much of the problems associated with the earlier synthesis. With this porphyrin it is possible to build hetero-complementary rigid, multi-porphyrin supramolecular arrays via hydrogen bonds. For example, when using naphthalenediimide (NDI) units a checkerboard pattern is expected to be formed using this porphyrin as a donor and NDI as an acceptor where triple hydrogen bond is formed between the diimide and pyridyl units. Energy transfer can be studied through this hydrogen bonded supramolecular assembly. The synthesis of a triply bridged diporphyrin appended with six thioglucose units is reported. The electronic spectrum of this triply bridged porphyrin has enhanced intensity at low-energy wavelengths that reaches the near infrared region. The goal of this project is to create tumor targeting dyes that can be activated with red wavelengths of light that penetrate deeper into tissues. This new compound is amphiphilic in nature, chemically and photochemically stable, expected to have unusual photophysical and electrochemical properties, and can potentially be used as a photosensitizer in photodynamic therapy.

Controlled release formulations of Atrazine and Mesotrione: characterization and sorption on soils

NASA Astrophysics Data System (ADS)

Pinheiro Dick, D.; Gomes de Ávila, L.; Benvenuti Leite, S.; Raffin Pohlmann, A.

2009-04-01

Atrazine is a widely used herbicide on corn and sugar cane plantations, which, along with soybeans, are the most productive crops in Brazil and are responsible for 36.5% of the annual national consumption of herbicides. Mesotrione is a new herbicide registered in the last years used for controlling weeds in corn plantations as a tentative substitution for atrazine. After its application in the field, reactions between the herbicide and chemical groups from the soil matrix surface occur, and this complexed form remains in the soil, representing a potential source for environmental contamination and also affecting its agronomic efficiency. Therefore, the application of herbicides associated to carrier systems may represent an alternative to mitigate the environmental impact caused by their intense usage, considering that the interaction between the soil matrix and the xenobiotic is reduced, and thus, diminishes the recommended dosis and reduces the environmental pollution. The objectives of this study are to evaluate the chemical and morphological characteristics of controlled release formulations of atrazine (ATZ) and of mesotrione (MES) and to investigate their sorptive behavior in three representative Brazilian soils. To assess the feasibility of using these associated systems, four formulations (SGATZ) containing different concentrations of atrazine and four formulations (SGMES) containing different levels of mesotrione (MES) were synthesized by the sol-gel method (SG), using tetraetil-ortho-silicate as precursor and NaF as catalyst. The formulations were characterized by elemental analysis, adsorption and desorption isotherms of nitrogen, thermal analysis (DSC), scanning electron microscopy (SEM) and infrared spectroscopy (FTIR). For comparison, samples of pure xerogel (SG), commercial MES (Callisto-Syngenta), pure ATZ (99% of active principle, Milênia), granulated ATZ (Gesaprim GrDA Syngenta) and dried commercial ATZ (Nortox 500 SC) were analyzed. The herbicides release from the formulations and from the commercial products in CaCl2 0,01 mol.L-1 medium was quantified by UV/vis spectroscopy along 24 hours. Mathematical models were tested in order to establish the release kinetics. Sorption isotherms of the formulations SGATZ150 and of the SGMES150 and of the comercial products were determined in three types of soil. The ATZ yields in the formulations were around 60%, while for MES the values reached 80%. In all formulations, ATZ was physically dispersed on the Si-polymer, and the dispersion grade decreased with increasing amount of added herbicide. The same behaviour was shown by MES. Both dissolution and diffusion processes controlled the release kinetics of ATZ from the formulations, whose data was fitted to the Korsmeyer-Peppas model. With the decrease of ATZ dispersion, the mechanism of dissolution assumes a more important role. In the case of MES, the dissolution to the aqueous media was rapidly achieved and the hebiced was located mostly outside the carrier polymer. Nevertheles, both herbicides in the form of xerogel presented a lower affinity for soil than in the commercial form. However, in soils with high contents of organic matter, the retention of ATZ in high affinity sorptive sites occurs both with the herbicide in molecular form as well as bound to the sol-gel matrix.

Strengths of primary healthcare regarding care provided for chronic kidney disease.

PubMed

Paula, Elaine Amaral de; Costa, Mônica Barros; Colugnati, Fernando Antonio Basile; Bastos, Rita Maria Rodrigues; Vanelli, Chislene Pereira; Leite, Christiane Chaves Augusto; Caminhas, Márcio Santos; Paula, Rogério Baumgratz de

2016-09-09

to assess the structure and results obtained by the "Chronic Renal Patients Care Program" in a Brazilian city. epidemiological, cross-sectional study conducted in 14 PHC units and a secondary center from 2010 to 2013. The Donabedian Model was the methodological framework used. A total of 14 physicians, 13 supervisors, and 11 community health agents from primary healthcare were interviewed for the assessment of structure and process and 1,534 medical files from primary healthcare and 282 from secondary care were consulted to assess outcomes. most units lacked sufficient offices for physicians and nurses to provide consultations, had incomplete staffing, and most professionals had not received proper qualification to provide care for chronic renal disease. Physicians from PHC units classified as capable more frequently referred patients to the secondary care service in the early stages of chronic renal disease (stage 3B) when compared to physicians of units considered not capable (58% vs. 36%) (p=0.049). Capable PHC units also more frequently presented stabilized glomerular filtration rates (51%) when compared to partially capable units (36%) and not capable units (44%) (p=0.046). patients cared for by primary healthcare units that scored higher in structure and process criteria presented better clinical outcomes. to identify the coping strategies of family members of patients with mental disorders and relate them to family member sociodemographic variables and to the patient's clinical variables. this was a descriptive study conducted at a psychiatric hospital in the interior of the state of São Paulo, with 40 family members of hospitalized patients over the age of 18, and who followed the patient before and during hospitalization. We used tools to characterize the subjects and the Folkman and Lazarus Inventory of Coping Strategies. the coping strategies most often used by family members were social support and problem solving. Mothers and fathers used more functional strategies (self-control p=0.037, positive reappraisal p=0.037, and social support p=0,021). We found no significant differences between the strategies and other variables examined. despite the suffering resulting from the illness of a dear one, family members make more use of functional strategies, allowing them to cope with adversities in a more well-adjusted way. avaliar estrutura, processo e resultado do "Programa de Atenção a Doentes Renais Crônicos" em um município brasileiro. estudo epidemiológico, transversal, realizado em 14 unidades de atenção primária e um centro de atenção secundária, no período de 2010-2013. Utilizou-se o referencial metodológico de Donabedian. Para avaliação de estrutura e processo, foram entrevistados 14 médicos, 13 supervisores e 11 agentes comunitários de saúde da atenção primária. Para avaliação de resultado, foram utilizados 1.534 prontuários de saúde na atenção primária e 282 na atenção secundária. na maioria das unidades faltam consultórios para atendimento médico e de enfermagem, as equipes estavam incompletas e a maioria dos profissionais não participou de capacitação para atenção à doença renal crônica. Médicos das unidades primárias, classificadas como capacitadas, encaminharam usuários à atenção secundária em estágios mais precoces da doença renal crônica (estágio 3B) quando comparados aos médicos das unidades não capacitadas (58% vs 36%) (p=0,049). As unidades de atenção primária, classificadas como capacitadas, apresentaram melhores taxas de estabilização da filtração glomerular (51%) quando comparadas às unidades parcialmente capacitadas (36%) e não capacitadas (44%) (p=0,046). usuários atendidos nas unidades de atenção primária com pontuação mais elevada em critérios de estrutura e processo apresentaram melhores resultados clínicos. evaluar la estructura, el proceso y los resultados del "Programa de Atención a Enfermos Renales Crónicos" en un municipio brasileño. estudio epidemiológico, transversal, realizado en 14 unidades de atención primaria y en un centro de atención secundario, en el período de 2010 a 2013. Se utilizó el referencial metodológico de Donabedian. Para evaluación de estructura y proceso; fueron entrevistados 14 médicos, 13 supervisores y 11 agentes comunitarios de salud de la atención primaria. Para evaluación del resultado, fueron utilizadas 1.534 fichas médicas en la atención primaria y 282 en la atención secundaria. en la mayoría de las unidades faltaban consultorios para la atención médica y de enfermería, los equipos estaban incompletos y la mayoría de los profesionales no participó de capacitaciones sobre la atención a la enfermedad renal crónica. Los médicos de las unidades primarias, clasificados como capacitados, encaminaron usuarios para la atención secundaria en etapas más precoces de la enfermedad renal crónica (etapa 3B) cuando comparados a los médicos de las unidades no capacitadas (58% vs 36%) (p=0,049). Las unidades de atención primaria, clasificadas como capacitadas, presentaron mejores tasas de estabilización de la filtración glomerular (51%) cuando comparadas a las unidades parcialmente capacitadas (36%) y no capacitadas (44%) (p=0,046). los usuarios atendidos en las unidades de atención primaria, con puntuación más elevada en criterios de estructura y proceso, presentaron mejores resultados clínicos.

Tribosystems based on multilayered micro/nanocrystalline CVD diamond coatings =

NASA Astrophysics Data System (ADS)

Shabani, Mohammadmehdi

A combinacao das caracteristicas do diamante microcristalino (MCD) e nanocristalino (NCD), tais como elevada adesao do MCD e a baixa rugosidade superficial e baixo coeficiente de atrito do NCD, e ideal para aplicacoes tribologicas exigentes. Deste modo, o presente trabalho centrou-se no desenvolvimento de revestimentos em multicamada MCD/NCD. Filmes com dez camadas foram depositados em amostras de cerâmicos de Si3N4 pela tecnica de deposicao quimica em fase vapor assistida por filamento quente (HFCVD). A microestrutura, qualidade do diamante e adesao foram investigadas usando tecnicas como SEM, AFM, espectroscopia Raman, DRX, indentacao Brale e perfilometria otica 3D. Diversas geometrias para aplicacoes distintas foram revestidas: discos e esferas para testes tribologicos a escala laboratorial, e para testes em servico, aneis de empanques mecânicos e pastilhas de corte para torneamento. Nos ensaios tribologicos esfera-sobre-plano em movimento reciproco, sob 10-90% de humidade relativa (RH), os valores medios dos coeficientes de atrito maximo e em estado estacionario sao de 0,32 e 0,09, respetivamente. Em relacao aos coeficientes de desgaste, observou-se um valor minimo de cerca de 5,2x10-8 mm3N-1m-1 para valores intermedios de 20-25% de RH. A humidade relativa tem um forte efeito sobre o valor da carga critica que triplica a partir de 40 N a 10% RH para 120 N a 90% de RH. No intervalo de temperaturas 50-100 °C, as cargas criticas sao semelhantes as obtidas em condicoes de baixa RH ( 10-25%). A vida util das ferramentas com revestimento de dez camadas alternadas MCD/NCD e 24 mum de espessura total no torneamento de um composito de matriz metalica Al- 15 vol% Al2O3 (Al-MMC) e melhor do que a maioria das ferramentas de diamante CVD encontradas na literatura, e semelhante a maioria das ferramentas de diamante policristalino (PCD). A formacao de cratera ocorre por desgaste sucessivo das varias camadas, atrasando a delaminacao total do revestimento de diamante do substrato, ao contrario do que acontece com os revestimentos monocamada. Os aneis de empanque testados com biodiesel apresentaram coeficientes de desgaste (4,1x10-10 mm3N-1m-1) duas ordens de grandeza menores do que em ensaios esfera-sobre-plano em movimento reciproco (k = 5,0x10-8 mm3N-1m-1), mas nao foi possivel obter vedacao completa devido a sobreaquecimento do fluido. Esta condicao foi obtida com agua sob pressao, para condicoes P.V na gama 0,72-5,3 MPa.ms-1. Um coeficiente de atrito em estado estacionario de 0,04 e um valor de coeficiente de desgaste de 6,0x10-10 mm3N-1m-1, caracteristico de um regime desgaste ultra-suave, revelam o alto desempenho deste tribossistema.

MORTALITY OF URGENCY VERSUS ELECTIVE VIDEOLAPAROSCOPIC CHOLECYSTECTOMY FOR ACUTE CHOLECYSTITIS.

PubMed

Felício, Saulo José Oliveira; Matos, Ediriomar Peixoto; Cerqueira, Antonio Maurício; Farias, Kurt Wolfgang Schindler Freire de; Silva, Ramon de Assis; Torres, Mateus de Oliveira

2017-01-01

Surgical approach is still controversial in patients with acute cholecystitis: to treat clinically the inflammatory process and operate electively later or to operate immediately on an emergency basis? To test the hypothesis that urgent laparoscopic cholecystectomy in acute cholecystitis has a higher mortality than elective laparoscopic cholecystectomy. From the data available in Datasus, mortality was compared between patients undergoing elective laparoscopic cholecystectomy for cholelithiasis and in urgency. Calculations were made of the relative reduction in risk of death, absolute reduction of risk of death and number needed to treat. From 2009 to 2014 in Brazil, there were 250.439 laparoscopic cholecystectomy and 74.6% were electives. Mortality in the emergency group was 4.8 times higher compared to the elective group (0.0023% vs. 0.00048%). Despite the relative reduction in risk of death (RRR) was 83%, in the calculation of absolute risk was found 0.0018 and number needed to treat of 55,555. Despite the relative risk reduction for mortality was high comparing elective vs. urgent basis, the absolute risk reduction was minimal, since this outcome is very low in both groups, suggesting that mortality should not have much influence on surgical decision. Continua controversa a conduta nos pacientes com colecistite aguda: compensar o processo inflamatório e operar eletivamente ou operar imediatamente em caráter de urgência? Testar a hipótese de que a colecistectomia videolaparoscópica de urgência por colecistite aguda apresenta maior mortalidade que a colecistectomia videolaparoscópica eletiva. A partir dos dados disponíveis no Datasus, foi comparada a mortalidade entre os pacientes submetidos à colecistectomia videolaparoscópica eletiva por colelitíase e a de urgência. Foram realizados cálculos da redução relativa de risco de morte, redução absoluta do risco de morte e número necessário para tratar . De 2009 a 2014 no Brasil, foram realizadas 250.439 colecistectomias videolaparoscópicas sendo 74,6% eletivas. A mortalidade no grupo de emergência foi 4,8 vezes mais elevada em comparação com o grupo eletivo (0,0023% vs. 0,00048%). Apesar da redução relativa do risco de morte (RRR) ser de 83%, no cálculo do risco absoluto encontrou-se 0,0018 e número necessário para tratar de 55.555. Apesar da redução relativa de risco para mortalidade ser alta comparando o caráter eletivo vs. urgência, a redução de risco absoluto é mínima, já que esse desfecho é muito baixo nos dois grupos, sugerindo que a mortalidade não deve ter muita influência na tomada de decisão cirúrgica.

Achieving Conservation Science that Bridges the Knowledge–Action Boundary

PubMed Central

Cook, Carly N; Mascia, Michael B; Schwartz, Mark W; Possingham, Hugh P; Fuller, Richard A

2013-01-01

There are many barriers to using science to inform conservation policy and practice. Conservation scientists wishing to produce management-relevant science must balance this goal with the imperative of demonstrating novelty and rigor in their science. Decision makers seeking to make evidence-based decisions must balance a desire for knowledge with the need to act despite uncertainty. Generating science that will effectively inform management decisions requires that the production of information (the components of knowledge) be salient (relevant and timely), credible (authoritative, believable, and trusted), and legitimate (developed via a process that considers the values and perspectives of all relevant actors) in the eyes of both researchers and decision makers. We perceive 3 key challenges for those hoping to generate conservation science that achieves all 3 of these information characteristics. First, scientific and management audiences can have contrasting perceptions about the salience of research. Second, the pursuit of scientific credibility can come at the cost of salience and legitimacy in the eyes of decision makers, and, third, different actors can have conflicting views about what constitutes legitimate information. We highlight 4 institutional frameworks that can facilitate science that will inform management: boundary organizations (environmental organizations that span the boundary between science and management), research scientists embedded in resource management agencies, formal links between decision makers and scientists at research-focused institutions, and training programs for conservation professionals. Although these are not the only approaches to generating boundary-spanning science, nor are they mutually exclusive, they provide mechanisms for promoting communication, translation, and mediation across the knowledge–action boundary. We believe that despite the challenges, conservation science should strive to be a boundary science, which both advances scientific understanding and contributes to decision making. Logrando que la Ciencia de la Conservación Trasponga la Frontera Conocimiento-Acción Resumen Hay muchas barreras para utilizar ciencia para informar a la política y práctica de la conservación. Los científicos de la conservación que desean producir ciencia relevante para el manejo deben equilibrar esta meta con el imperativo de demostrar novedad y rigor en su ciencia. Los tomadores de decisiones que buscan que sus decisiones se basen en evidencias deben equilibrar el deseo de conocimientos con la necesidad de actuar a pesar de la incertidumbre. La generación de ciencia que informe efectivamente a las decisiones de manejo requiere que la producción de información (los componentes del conocimiento) sea sobresaliente (relevante y oportuna), creíble (autoritativa, verosímil y confiable) y legítima (desarrollada mediante un proceso que considera los valores y perspectivas de todos los actores relevantes) a la vista tanto de investigadores como de tomadores de decisiones. Percibimos tres retos clave para quienes desean generar ciencia de la conservación que logre estas tres características de la información. Primero, las audiencias científicas y de manejo pueden tener percepciones contrastantes sobre la relevancia de la investigación. Segundo, la credibilidad se puede lograr a costa de la relevancia y legitimidad a la vista de los tomadores de decisiones y tercero, los diferentes actores pueden tener percepciones conflictivas sobre los que constituye información legítima. Resaltamos cuatro marcos institucionales que pueden facilitar que la ciencia informe al manejo: organizaciones de frontera (organizaciones ambientales que trasponen la frontera entre la ciencia y el manejo), investigadores científicos insertados en agencias de manejo de recursos, vínculos formales entre tomadores de decisiones y científicos en instituciones enfocadas a la investigación, y programas de capacitación para profesionales de la conservación. Aunque estos no son los únicos métodos para generar ciencia que traspone fronteras, ni son mutuamente excluyentes, proporcionan mecanismos que promueven la comunicación, traslación y mediación para trasponer la frontera conocimiento-acción. Consideramos que no obstante los retos, la ciencia de la conservación debería pugnar por ser una ciencia de frontera, que incrementa el entendimiento científico y contribuye a la toma de decisiones. PMID:23574343

Global Longitudinal Strain or Left Ventricular Twist and Torsion? Which Correlates Best with Ejection Fraction?

PubMed

Lima, Marcio Silva Miguel; Villarraga, Hector R; Abduch, Maria Cristina Donadio; Lima, Marta Fernandes; Cruz, Cecilia Beatriz Bittencourt Viana; Sbano, João Cesar Nunes; Voos, Mariana Callil; Mathias, Wilson; Tsutsui, Jeane Mike

2017-07-01

Estimative of left ventricular ejection fraction (LVEF) is a major indication for echocardiography. Speckle tracking echocardiography (STE) allows analysis of LV contraction mechanics which includes global longitudinal strain (GLS) and twist/torsion, both the most widely used. Direct comparison of correlations between these novel parameters and LVEF has never been done before. This study aims to check which one has the highest correlation with LVEF. Patients with normal LVEF (> 0,55) and systolic dysfunction (LVEF <0,55) were prospectively enrolled, and underwent echocardiogram with STE analysis. Correlation of variables was performed by linear regression analysis. In addition, correlation among levels of LV systolic impairment was also tested. A total of 131 patients were included (mean age, 46 ± 14y; 43%, men). LVEF and GLS showed a strong correlation (r = 0.95; r2 = 0.89; p < 0.001), more evident in groups with LV systolic dysfunction than those with preserved LVEF. Good correlation was also found with global longitudinal strain rate (r = 0.85; r2 = 0.73; p < 0.001). Comparing to GLS, correlation of LVEF and torsional mechanics was weaker: twist (r = 0.78; r2 = 0.60; p < 0.001); torsion (r = 0.75; r2 = 0.56; p < 0.001). GLS of the left ventricle have highly strong positive correlation with the classical parameter of ejection fraction, especially in cases with LV systolic impairment. Longitudinal strain rate also demonstrated a good correlation. GLS increments analysis of LV systolic function. On the other hand, although being a cornerstone of LV mechanics, twist and torsion have a weaker correlation with LV ejection, comparing to GLS. A estimativa da fração de ejeção do ventrículo esquerdo (FEVE) é uma das pincipais indicações para a ecocardiografia. Speckle tracking (ST) permite a análise da mecânica de contração do VE que inclui a deformação (strain) longitudinal global (SLG) e o twist / torção, sendo ambos os mais utilizados. A comparação direta de correlações entre esses novos parâmetros e a FEVE nunca foi feita antes. Verificar qual delas tem a maior correlação com a FEVE. Pacientes com FEVE normal (> 0,55) e disfunção sistólica (FEVE < 0,55) foram prospectivamente inscritos e submetidos a ecocardiograma com análise do ST. A correlação das variáveis foi realizada por análise de regressão linear. Além disso, também foi testada a correlação entre os níveis de comprometimento sistólico do VE. Foram incluídos 131 pacientes (média de idade de 46 ± 14 anos e 43% de homens). A FEVE e SLG apresentaram forte correlação (r = 0,95; r2 = 0,89; p < 0,001), mais evidente em grupos com disfunção sistólica do VE do que naqueles com FEVE preservada. Também foi encontrada boa correlação com a taxa de deformação (strain rate) longitudinal (SRL) global (r = 0,85; r2 = 0,73; p < 0,001). Comparando-a à SLG, a correlação entre FEVE e mecânica de torção foi mais fraca: twist (r = 0,78; r2 = 0,60; p < 0,001); Torção (r = 0,75, r2 = 0,56, p < 0,001). A SLG do ventrículo esquerdo apresenta alta correlação positiva com o parâmetro clássico de fração de ejeção, principalmente nos casos de comprometimento sistólico do VE. O SRL também demonstrou uma boa correlação. A SLG incrementa a análise da função sistólica do VE. Por outro lado, apesar de ser a pedra angular da mecânica do VE, o twist e a torção têm uma correlação mais fraca com a ejeção do VE, quando comparados ao SLG.

Dinámica y crecimiento de los granos de polvo en la nebulosa protoplanetaria

NASA Astrophysics Data System (ADS)

de La Fuente Marcos, Carlos

2001-06-01

En el escenario estándar de la formación planetaria, los planetesimales (cuerpos de tamaño kilométrico) crecen a partir de granos de polvo, similares a los interestelares, embebidos en un disco gaseoso denominado nebulosa protoplanetaria. Durante esta etapa, los movimientos del gas pueden tener gran influencia en la dinámica y el crecimiento de los granos de polvo, dado que el flujo kepleriano del gas frena el movimiento de los mismos haciendo que caigan hacia el Sol, y la turbulencia inhibe la inestabilidad gravitacional de la capa de polvo. Aunque se acepta que los planetesimales fueron los elementos constituyentes de los planetas, todavía se desconoce cómo se produjo la formación de los mismos. Por esta razón, en los estudios más recientes, existe un renovado interés por comprender mejor la evolución de la capa de polvo inmersa en el disco gaseoso de la Nebulosa. El gas que fluye en el disco puede engendrar estructuras carentes de simetría axial, como por ejemplo ondas espirales y vórtices, a partir de gran variedad de mecanismos de excitación e inestabilidad. En 1995, Barge y Sommeria pusieron de manifiesto que la existencia de vórtices gaseosos persistentes en la nebulosa solar tendría importantes consecuencias sobre la formación de los planetesimales y el posterior crecimiento de los planetas gigantes. La investigación desarrollada en esta Tesis analiza la relación entre el polvo y el gas debida al acoplamiento por fricción dinámica entre ambos; en concreto, se estudia el efecto del flujo medio del gas sobre la dinámica de las partículas de polvo. El primer objetivo es investigar en profundidad los procesos de captura y crecimiento de los granos de polvo dentro de un vórtice y su posible relevancia en cuanto a la formación de los planetesimales. El segundo objetivo es la exploración de los efectos de ondas espirales propagándose en el disco gaseoso sobre la dinámica y el crecimiento de las partículas. La presencia de líneas de corriente no circulares perturba significativamente el movimiento de las partículas alrededor del Sol e incrementa su vida media en la Nebulosa. El flujo medio del gas se modela de forma simple, analizándose la dinámica y el crecimiento de las partículas mediante simulaciones numéricas. Al incrementarse la vida media y la densidad superficial de las partículas sólidas, los mecanismos de confinamiento derivados de la presencia de vórtices y ondas espirales actuan sobre el material sólido de la Nebulosa (mediante agregación colisional o inestabilidades gravitacionales) de manera mucho más eficiente que la previamente considerada. Esto ofrece nuevas posibilidades para la formación de planetesimales y núcleos de planetas gigantes, y puede explicar la formación rápida de planetas extrasolares gigantes. Además, esta Tesis analiza la respuesta de las partículas, en un disco protoplanetario con un radio de 100 UA en torno a una estrella de tipo solar, al campo gravitatorio derivado de la presencia de dos estrellas compañeras ligadas en una órbita relativamente elongada (300-1600 UA). Para llevar a cabo este análisis, se han realizado una serie de simulaciones numéricas de configuraciones jerárquicas coplanares utilizando un programa FORTRAN que integra directamente las ecuaciones del movimiento con el objeto de modelar la presencia de las fuerzas gravitacionales y viscosas. El disco protoplanetario masivo se encuentra en torno a una de las componentes de la binaria. La evolución temporal del subdisco de polvo depende directamente de la naturaleza (directa o retrógrada) de la revolución relativa de la compañera estelar, y de la temperatura y la masa del disco circunestelar.

Establishment of Lipolexis oregmae (Hymenoptera: Aphidiidae) in a classical biological control program directed against the brown citrus aphid (Homoptera: Aphididae) in Florida

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

Persad, A.B.; Hoy, M.A.; Ru Nguyen

The parasitoid Lipolexis oregmae Gahan (introduced as L. scutellaris Mackauer) was imported from Guam, evaluated in quarantine, mass reared, and released into citrus groves in Florida in a classical biological control program directed against the brown citrus aphid, Toxoptera citricida Kirkaldy. Releases of 20,200, 12,100, and 1,260 adults of L. oregmae were made throughout Florida during 2000, 2001, and 2002, respectively. To determine if L. oregmae had successfully established, surveys were conducted throughout the state beginning in the summer of 2001 and continuing through the summer of 2003. Parasitism during 2001 and 2002 was evaluated by holding brown citrus aphidsmore » in the laboratory until parasitoid adults emerged. Lipolexis oregmae was found in 10 sites in 7 counties and 4 sites in 3 counties with parasitism rates ranging from 0.7 to 3.3% in 2001 and 2002, respectively. Laboratory tests indicated that high rates of mortality occurred if field-collected parasitized aphids were held in plastic bags, so a molecular assay was used that allowed immature L. oregmae to be detected within aphid hosts immediately after collection. The molecular assay was used in 2003 with the brown citrus aphids and with other aphid species collected from citrus, weeds, and vegetables near former release sites; immatures of L. oregmae were detected in black citrus aphids, cowpea aphids, spirea aphids, and melon aphids, as well as in the brown citrus aphid, in 4 of 8 counties sampled, with parasitism ranging from 2.0 to 12.9%, indicating that L. oregmae is established and widely distributed. Samples taken in Polk County during Oct 2005 indicated that L. oregmae has persisted. The ability of L. oregmae to parasitize other aphid species on citrus, and aphids on other host plants, enhances the ability of L. oregmae to persist when brown citrus aphid populations are low. (author) [Spanish] El parasitoide Lipolexis oregmae Gahan (introducido como L. scutellaris Mackauer) fue importado de Guam, evaluado en cuarentena, criado en masa y liberado en huertos de citricos en un programa de control biologico clasico dirigido contra el afido pardo de citricos, Toxoptera citricida Kirkaldy. Se hicieron liberaciones de 20,200, 12,100, y 1,260 adultos de L. oregmae a traves de la Florida durante los anos de 2000, 2001, y 2002, respectivamente. Para determinar si L. oregmae ha logrado en establecer, se realizaron sondeos a traves del estado empezando en el verano del 2001 y continuando hasta el final del verano del 2003. El parasitismo durante 2001 y 2002 fue evaluado con el mantenimiento de individuos del afido pardo de los citricos en el laboratorio hasta que los adultos emergieron. Lipolexis oregmae fue encontrado en 10 sitios en 7 condados y con tasas de parasitismo en 4 sitios en 3 condados entre 0.7 a 3.3% en el 2001 y 2002, respectivamente. Las pruebas del laboratorio indicaron que las tasas altas de mortalidad fueron posibles si los afidos con parasitos recolectados en el campo fueron mantenidos en bolsas plasticas, entonces un ensayo molecular fue usado con lo que permitio la deteccion de inmaduros de L. oregmae dentro de los hospederos de afidos inmediatamente despues de la recoleccion. El ensayo molecular fue usado en el 2003 con individuos del afido pardo de los citricos y con otras especies de afidos recolectados sobre citricos, malezas y hortalizas cerca de los sitios donde los parasitoides fueron liberados anteriormente; inmaduros de L. oregmae fueron detectados en individuos del afido negro de los citricos, el afido del caupi, el afido spirea y el afido del melon, ademas del afido pardo de los citricos en 4 de los 8 condados muestreados, con la tasa del parasitismo entre 2.0 a12.9%, indicando que L. oregmae estaba estabecido y ampliamente distribuido. Las muestras tomadas en el Condado de Polk durante octobre del 2005 indicaron que L. oregmae ha persistido. La capacidad de L. oregmae para parasitar otras especies de afidos sobre citricos y otros afidos sobre otras plantas hospederas, incrementa la capacidad de L. oregmae para persistir cuando las poblaciones del afido pardo de los citricos estan bajas. (author)« less

Single-dose systemic methotrexate vs expectant management for treatment of tubal ectopic pregnancy: a placebo-controlled randomized trial.

PubMed

Jurkovic, D; Memtsa, M; Sawyer, E; Donaldson, A N A; Jamil, A; Schramm, K; Sana, Y; Otify, M; Farahani, L; Nunes, N; Ambler, G; Ross, J A

2017-02-01

Methotrexate is used routinely worldwide for the medical treatment of clinically stable women with a tubal ectopic pregnancy. This is despite the lack of robust evidence to show its superior effectiveness over expectant management. The aim of our multicenter randomized controlled trial was to compare success rates of methotrexate against placebo for the conservative treatment of tubal ectopic pregnancy. This study took place in two early-pregnancy units in the UK between August 2005 and June 2014. Inclusion criteria were clinically stable women with a conclusive ultrasound diagnosis of a tubal ectopic pregnancy, presenting with a low serum beta human chorionic gonadotropin (β-hCG) level of < 1500 IU/L. Women were assigned randomly to a single systemic injection of either 50 mg/m 2 methotrexate or placebo. The primary outcome was a binary indicator for success of conservative management, defined as resolution of clinical symptoms and decline of serum β-hCG to < 20 IU/L or a negative urine pregnancy test without the need for any additional medical intervention. An intention-to-treat analysis was followed. We recruited a total of 80 women, 42 of whom were assigned to methotrexate and 38 to placebo. The arms of the study were matched in terms of age, ethnicity, obstetric history, pregnancy characteristics and serum levels of β-hCG and progesterone. The rates of success were similar for the two study arms: 83% with methotrexate and 76% with placebo. On univariate analysis, this difference was not statistically significant (χ 2 (1 degree of freedom) = 0.53; P = 0.47). On multivariate logistic regression, the serum level of β-hCG was the only covariate found to be significantly associated with outcome. The odds of failure increased by 0.15% for each unit increase in β-hCG (odds ratio, 1.0015 (95% CI, 1.0002-1.003); P = 0.02). In 14 women presenting with serum β-hCG of 1000-1500 IU/L, the success rate was 33% in those managed expectantly compared with 62% in those receiving methotrexate. This difference was not statistically significant and a larger sample size would be needed to give sufficient power to detect a difference in the subgroup of women with higher β-hCG. In women with successful conservative treatment, there was no significant difference in median β-hCG resolution times between study arms (17.5 (interquartile range (IQR), 14-28.0) days (n = 30) in the methotrexate group vs 14 (IQR, 7-29.5) days (n = 25) in the placebo group; P = 0.73). The results of our study do not support the routine use of methotrexate for the treatment of clinically stable women diagnosed with tubal ectopic pregnancy presenting with low serum β-hCG (< 1500 IU/L). Further work is required to identify a subgroup of women with tubal ectopic pregnancy and β-hCG ≥ 1500 IU/L in whom methotrexate may offer a safe and cost-effective alternative to surgery. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Comparación entre una sola dosis de metotrexate sistémico y la conducta expectante en el tratamiento de casos de embarazo ectópico tubárico: un ensayo aleatorio controlado con placebo RESUMEN OBJETIVO: El metotrexate se utiliza de modo rutinario en todo el mundo para el tratamiento de las mujeres clínicamente estables con un embarazo ectópico tubárico. Esto sucede a pesar de la falta de evidencia rigurosa que demuestre que su eficacia es superior a la conducta expectante. El objetivo de este ensayo controlado aleatorio multicéntrico fue comparar las tasas de éxito del metotrexate con las de un placebo para el tratamiento cauteloso del embarazo ectópico tubárico. MÉTODOS: Este estudio se llevó a cabo en dos clínicas de control de gestación temprana en el Reino Unido entre agosto de 2005 y junio de 2014. Los criterios de inclusión fueron mujeres clínicamente estables con un diagnóstico ecográfico concluyente de embarazo ectópico tubárico, las cuáles presentaban una concentración sérica baja de la β hormona coriónica gonadotrópica (β-hCG) inferior a 1500 UI/L. Las mujeres fueron asignadas aleatoriamente a una sola inyección sistémica de 50 mg/m2 de metotrexate o a placebo. El resultado primario fue un indicador binario del éxito del tratamiento conservador, definido como la resolución de los síntomas clínicos y la disminución en el suero de la β-hCG a <20 UI/L o una prueba de embarazo negativa en orina sin la necesidad de ninguna intervención médica adicional. Se hizo un análisis por intención de tratar. Se reclutó un total de 80 mujeres; a 42 de ellas se les asignó el metotrexate y a 38 el placebo. Los grupos del estudio se realizaron en función de la edad, el origen étnico, los antecedentes obstétricos, las características del embarazo y los niveles séricos de la β-hCG y la progesterona. Las tasas de éxito fueron similares para los dos grupos de estudio: 83% con metotrexate y 76% con placebo. En el análisis univariante, esta diferencia no fue estadísticamente significativa (χ2 (1 grado de libertad) = 0,53; P = 0,47). En la regresión logística multivariante, el nivel sérico de la β-hCG fue la única covariable que se encontró significativamente asociada con el resultado. Las probabilidades de fracaso aumentaron en un 0,15% por cada unidad de aumento de la β-hCG (cociente de probabilidad 1,0015 (IC 95%, 1,0002-1,003); P = 0,02). La tasa de éxito en las 14 mujeres con un nivel sérico de la β-hCG de 1000-1500 UI/L fue del 33% en las tratadas con conducta expectante frente al 62% en las que recibieron metotrexate. Esta diferencia no fue estadísticamente significativa, por lo que se necesitaría un tamaño de muestra mayor, lo suficiente como para poder detectar diferencias en el subgrupo de mujeres con una β-hCG más elevada. En las mujeres en las que el tratamiento conservador tuvo éxito, no hubo una diferencia significativa en la mediana de los tiempos de resolución de la ß-hCG entre los grupos del estudio (17,5 (amplitud intercuartílica (IQR), 14-28,0) días (n = 30) en el grupo de metotrexate frente a 14 (IQR, 7-29.5) días (n = 25) en el grupo de placebo; P = 0,73). Los resultados de este estudio no apoyan el uso rutinario de metotrexate para el tratamiento de las mujeres clínicamente estables diagnosticadas con un embarazo ectópico tubárico que presenta un nivel sérico bajo la β-hCG (<1500 UI/L). Serán necesarios estudios adicionales para identificar un subgrupo de mujeres con embarazo ectópico tubárico y β-hCG ≥1500 UI/L para quienes el metotrexate puede ofrecer una alternativa segura y rentable en comparación con la cirugía. : : ,,。。 : 2005820146,2。,,β(beta human chorionic gonadotropin,β-hCG)<1500 IU/L。,(50 mg/m 2 )。,β-hCG<20 IU/L,。。 : 80,42,38。2、、、β-hCG。2:83%,76%。,[χ 2 (1)=0.53;P=0.47]。logistic,β-hCG。β-hCG,0.15%[,1.0015(95% CI,1.0002~1.003);P=0.02]。14β-hCG1000~1500 IU/L,33%,62%。,β-hCG。,2β-hCG(P=0.73),17.5[(interquartile range,IQR),14~28.0](n=30),14 (IQR,7~29.5)(n=25)。 : 、、β-hCG(<1500 IU/L)。,β-hCG>1500 IU/L、。. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Study of hydrogen in phthalocyanine semiconductors using muSR technique =

NASA Astrophysics Data System (ADS)

Duarte, Joao Pedro Piroto Pereira

Este trabalho apresenta um estudo experimental dos semicondutores organicos Ftalocianina (H2Pc), Ftalocianina de Zinco (ZnPc) e Ftalocianina de Cobre (CuPc) por tecnicas de µSR, tendo-se obtido informacao detalhada sobre a estrutura electronica dos estados de carga formados pelo muao positivo nos tres compostos, e sobre as interaccoes dinamicas a que esses estados se encontram sujeitos. Os resultados do estudo indicam que nas ftalocianias com caracter nao magneticas H2Pc e ZnPc se da a formacao de tres radicais muonicos paramagneticos distintos. A estrutura hiperfina destes radicais, referidos como estados I, II e III, foi caracterizada atraves da medida dos parametros de acoplamento hipefino em conjunto com a parameterizacao da sua dependencia com a temperatura. Uma quarta componente paramagnetica do sinal µSR foi tambem identificada, mas sobre a qual nao foi possivel retirar conclusoes definitivas quanto a sua origem. Verificou-se que os parametros de acoplamento hiperfino isotropicos dos tres estados identificados se encontram numa regiao de valores entre os 100 e os 150MHz para os estados I e II, enquanto que para o estado III esta quantidade toma valores em torno de 10 MHz. A estrutura electronica de todos os estados possui simetria axial, caracterizada por parametros dipolares de cerca de 15MHz para os estados I e II, e 20MHz para o estado III. A origem dos estados I e II foi determinada como sendo devida a adicao de muonio a uma das ligacoes duplas existentes nos aneis benzenicos da periferia das moleculas de ftalocianina recorrendo a calculos de estrutura electronica, tendo-se verificado a existencia de um acoplamento entre a interaccao hiperfina desses estados e modos vibracionais desses aneis. A problematica da localizacao do estado III tambem foi abordada, tomando-se como hipotese mais provavel uma posicao intersticial entre duas moleculas de ftalocianina. O estudo das interaccoes dinamicas de spin destes tres estados revelou que o estado III esta sujeito a um fenomeno de spin exchange, originado pela colisao com portadores de carga presentes no material. A taxa de spin-flip relativa a esta interaccao foi deduzida a partir de medidas µSR em geometria de campo longitudinal, tendo sida determinada a barreira energetica existente para a difusao de portadores de carga entre moleculas de ftalocianina localizadas dentro da mesma estrutura colunar tanto na H2Pc, como na ZnPc. Por fim, o sinal µSR da ftalocianina com caracter magnetico CuPc foi tambem caracterizado. Foram identificadas duas componentes de caracter aparentemente diamagnetico com taxas de relaxacao separadas por cerca de duas ordens de grandeza, atribuidas a duas configuracoes distintas para o emparelhamento entre o electrao do radical muonico, e o electrao com spin desemparelhado localizado no atomo de cobre. Os dois emparelhamentos diferentes geram um ambiente puramente diamagnetico para o muao, o que origina a componente de relaxacao lenta, e uma configuracao na qual existe uma densidade de spin flutuante na posicao do muao, responsavel pela componente de relaxacao elevada.

Frequency and risk factors for the birth of small-for-gestational-age newborns in a public maternity hospital.

PubMed

Teixeira, Marina Parca Cavelagna; Queiroga, Tatiana Peloso Reis; Mesquita, Maria Dos Anjos

2016-01-01

To determine the frequency and risk factors of small-for-gestational-age newborns in a high-risk maternity. This is an observational, cross-sectional, and case-control study, conducted in a public tertiary care maternity hospital. Data from 998 newborns and their mothers were collected through interviews and review of medical records and prenatal care cards. Some placentas underwent histopathological analysis. The variables of small-for-gestational-age and non-small-for-gestational-age newborns and of their mothers were statistically compared by means of Student's t test, Fisher's exact test, and odds ratio. The significance level used was 0.050. There was a 17.9% frequency of small-for-gestational-age newborns. The statistically significant factors associated with the birth of these babies were female sex (p=0.012); positive history of another small-for-gestational-age child (p=0.006); inadequate prenatal care (p=0.019); smoking (p=0.003); hypertensive disorders of pregnancy (p=0.007); placental bleeding (p=0.009) and infarction (p=0.001). In the population studied, the frequency of small-for-gestational-age newborns was high and associated with sex, inappropriate prenatal care, presence of maternal diseases and addictions, and placental abnormalities. Determinar a frequência e os fatores de risco de recém-nascidos pequenos para idade gestacional em uma maternidade de alto risco. Trata-se de um estudo observacional, transversal e caso-controle, realizado em maternidade pública de nível terciário. Foram levantados dados de 998 recém-nascidos e de suas respectivas mães por meio de entrevista e análise de prontuários e de cartões do pré-natal. Algumas placentas foram submetidas à análise anatomopatológica. As variáveis dos recém-nascidos pequenos e não pequenos para idade gestacional e de suas respectivas mães foram comparadas estatisticamente pelo teste paramétrico t de Student, pelo teste exato de Fisher e por odds ratio. O nível de significância adotado foi de 0,050. A frequência de recém-nascidos pequenos para idade gestacional foi de 17,9%. Os fatores com significado estatístico associados ao nascimento desses bebês foram sexo feminino (p=0,012); história positiva para filho anterior pequeno para idade gestacional (p=0,006); realização de pré-natal inadequado (p=0,019); tabagismo (p=0,003); doença hipertensiva específica da gestação (p=0,007); hemorragia (p=0,009) e infarto (p=0,001) placentários. Na população estudada, a frequência de recém-nascidos pequenos para idade gestacional foi elevada e relacionada ao sexo, à inadequação do pré-natal, à presença de doenças e vícios maternos e às alterações placentárias.

Compliance with the Prescription of Antihypertensive Medications and Blood Pressure Control in Primary Care.

PubMed

Novello, Mayra Faria; Rosa, Maria Luiza Garcia; Ferreira, Ranier Tagarro; Nunes, Icaro Gusmão; Jorge, Antonio José Lagoeiro; Correia, Dayse Mary da Silva; Martins, Wolney de Andrade; Mesquita, Evandro Tinoco

2017-02-01

Hypertension is the most prevalent risk factor for cardiovascular disease, and its proper control can prevent the high morbidity and mortality associated with this disease. To assess the degree of compliance of antihypertensive prescriptions with the VI Brazilian Guidelines on Hypertension and the blood pressure control rate in primary care. Cross-sectional study conducted between August 2011 and November 2012, including 332 adults ≥ 45 years registered in the Family Doctor Program in Niteroi and selected randomly. The analysis included the prescribed antihypertensive classes, doses, and frequencies, as well as the blood pressure (BP) of the individuals. The rate of prescription compliance was 80%. Diuretics were the most prescribed medications, and dual therapy was the most used treatment. The most common non-compliances were underdosing and underfrequencies. The BP goal in all cases was < 140/90 mmHg, except for diabetic patients, in whom the goal was set at < 130/80 mmHg. Control rates according to these goals were 44.9% and 38.6%, respectively. There was no correlation between prescription compliance and BP control. The degree of compliance was considered satisfactory. The achievement of the targets was consistent with national and international studies, suggesting that the family health model is effective in BP management, although it still needs improvement. A hipertensão arterial é o fator de risco mais prevalente para a doença cardiovascular e seu controle adequado pode prevenir a elevada morbi-mortalidade associada a esta doença. Avaliar o grau de conformidade das prescrições de anti-hipertensivos com as VI Diretrizes Brasileiras de Hipertensão e a taxa de controle pressórico na atenção básica. Estudo transversal conduzido entre agosto de 2011 e novembro de 2012, incluindo 332 adultos ≥ 45 anos cadastrados no Programa Médico de Família de Niterói e selecionados aleatoriamente. Foram analisadas as classes de anti-hipertensivos prescritos, suas doses e frequências, bem como a pressão arterial (PA) dos indivíduos. A taxa de conformidade das prescrições foi de 80%. Diuréticos foram as medicações mais prescritas e a terapia dupla foi o tratamento mais utilizado. As não conformidades mais comuns foram subdoses e subfrequências. A meta de PA para todos os casos foi < 140/90 mmHg, exceto para diabéticos, que foi < 130/80 mmHg. As taxas de controle de acordo com essas metas foram de 44,9% e 38,6%, respectivamente. Não houve correlação entre conformidade da prescrição e controle pressórico. O grau de conformidade foi considerado satisfatório. O alcance das metas foi compatível com estudos nacionais e internacionais, sugerindo que o modelo de saúde da família é efetivo no manejo da PA, embora ainda necessite aprimoramento. (Arq Bras Cardiol. 2017; [online].ahead print, PP.0-0).

Pulmonary function in children and adolescents with sickle cell disease: have we paid proper attention to this problem?

PubMed

Vieira, Ana Karine; Alvim, Cristina Gonçalves; Carneiro, Maria Cristina Marquez; Ibiapina, Cássio da Cunha

2016-01-01

To evaluate pulmonary function and functional capacity in children and adolescents with sickle cell disease. This was a cross-sectional study involving 70 children and adolescents (8-15 years of age) with sickle cell disease who underwent pulmonary function tests (spirometry) and functional capacity testing (six-minute walk test). The results of the pulmonary function tests were compared with variables related to the severity of sickle cell disease and history of asthma and of acute chest syndrome. Of the 64 patients who underwent spirometry, 15 (23.4%) showed abnormal results: restrictive lung disease, in 8 (12.5%); and obstructive lung disease, in 7 (10.9%). Of the 69 patients who underwent the six-minute walk test, 18 (26.1%) showed abnormal results regarding the six-minute walk distance as a percentage of the predicted value for age, and there was a ≥ 3% decrease in SpO2 in 36 patients (52.2%). Abnormal pulmonary function was not significantly associated with any of the other variables studied, except for hypoxemia and restrictive lung disease. In this sample of children and adolescents with sickle cell disease, there was a significant prevalence of abnormal pulmonary function. The high prevalence of respiratory disorders suggests the need for a closer look at the lung function of this population, in childhood and thereafter. Avaliar a função pulmonar e a capacidade funcional em crianças e adolescentes com doença falciforme. Estudo transversal com 70 crianças e adolescentes com doença falciforme (8-15 anos), submetidos a testes de função respiratória (espirometria) e de capacidade funcional (teste de caminhada de seis minutos). Os resultados da avaliação da função pulmonar foram comparados com variáveis relacionadas à gravidade da doença falciforme e à presença de história de asma e de síndrome torácica aguda. Dos 64 pacientes submetidos à espirometria, 15 (23,4%) apresentaram resultados alterados: distúrbio ventilatório restritivo, em 8; (12,5%) e distúrbio respiratório obstrutivo, em 7 (10,9%). Dos 69 pacientes submetidos ao teste de caminhada de seis minutos, 18 (26,1%) apresentaram resultados alterados na distância em % do previsto para a idade, e houve uma queda ≥ 3% na SpO2 em 36 (52,2%) dos pacientes. Não houve associações significativas entre função pulmonar alterada e as outras variáveis analisadas, exceto para hipoxemia e distúrbio ventilatório restritivo. Observou-se uma significativa prevalência de alterações na função pulmonar nesta amostra de crianças e adolescentes com doença falciforme. A elevada prevalência de distúrbios ventilatórios sugere a necessidade de um olhar mais atento à função pulmonar desde a infância nessa população.

Longitudinal hemodynamics in acute phase of treatment with labetalol in hypertensive pregnant women to predict need for vasodilatory therapy.

PubMed

Stott, D; Bolten, M; Paraschiv, D; Papastefanou, I; Chambers, J B; Kametas, N A

2017-01-01

Hypertensive pregnant women who do not respond to treatment with labetalol to control blood pressure (BP), but require vasodilatory therapy, progress rapidly to severe hypertension. This could be delayed by early recognition and individualized treatment. In this study, we sought to create prediction models from data at presentation and at 1 h and 24 h after commencement of treatment to identify patients who will not have a sustained response to labetalol and therefore need vasodilatory therapy. The study population comprised 134 women presenting with hypertension at a UK hospital. Treatment with oral labetalol was administered when BP was > 150/100 mmHg or > 140/90 mmHg with systemic disease. BP and hemodynamic parameters were recorded at presentation and at 1 h and 24 h after commencement of treatment. Labetalol doses were titrated to maintain BP around 135/85 mmHg. Women with unresponsive BP, despite labetalol dose maximization (2400 mg/day), received additional vasodilatory therapy with nifedipine. Binary logistic and longitudinal (mixed-model) data analyses were performed to create prediction models anticipating the likelihood of hypertensive women needing vasodilatory therapy. The prediction models were created from data at presentation and at 1 h and 24 h after treatment, to assess the value of central hemodynamics relative to the predictive power of BP, heart rate and demographic variables at these intervals. Twenty-two percent of our cohort required additional vasodilatory therapy antenatally. These women had higher rates of severe hypertension and delivered smaller babies at earlier gestational ages. The unresponsive women were more likely to be of black ethnicity, had higher BP and peripheral vascular resistance (PVR), and lower heart rate and cardiac output (CO) at presentation. Those who needed vasodilatory therapy showed an initial decrease in BP and PVR, which rebounded at 24 h, whereas BP and PVR in those who responded to labetalol showed a sustained decrease at 1 h and 24 h. Stroke volume and CO did not decrease during the acute phase of treatment in either group. The best model for prediction of the need for vasodilators was provided at 24 h by combining ethnicity and longitudinal BP and heart rate changes. The model achieved a detection rate of 100% for a false-positive rate of 20% and an area under the receiver-operating characteristics curve of 0.97. Maternal demographics and hemodynamic changes in the acute phase of labetalol monotherapy provide a powerful tool to identify hypertensive pregnant patients who are unlikely to have their BP controlled by this therapy and will consequently need additional vasodilatory therapy. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Las embarazadas hipertensas que no responden al tratamiento con labetalol para el control de la presión arterial (PA), pero que requieren terapia vasodilatadora, evolucionan rápidamente hacia una hipertensión severa. Ésta se puede retrasar mediante un diagnóstico precoz y un tratamiento individual. En este estudio se ha tratado de crear modelos de predicción a partir de datos al inicio del tratamiento y al cabo de 1 hora y de 24 horas después del mismo, para identificar a las pacientes que no mostrarán una respuesta constante al labetalol y que por lo tanto necesitarán terapia vasodilatadora. MÉTODOS: La población de estudio incluyó 134 mujeres con hipertensión en un hospital del Reino Unido. El tratamiento con labetalol por vía oral se administró cuando la PA fue >150/100 mm de Hg o >140/90 mm de Hg con enfermedad multisistémica. Se registró la PA y los parámetros hemodinámicos tanto al inicio como al cabo de 1 h y de 24 h después del inicio del tratamiento. Las dosis de Labetalol se ajustaron para mantener la PA en torno a los 135/85 mm de Hg. Las mujeres cuya PA no produjo respuesta, a pesar de haberles administrado la dosis máxima de labetalol (2400 mg/día), recibieron terapia vasodilatadora adicional con nifedipino. Se realizaron análisis de datos mediante logística binaria y longitudinal (modelo mixto), para crear modelos de predicción con los que pronosticar la probabilidad de la necesidad de terapia vasodilatadora en mujeres hipertensas. Los modelos de predicción se crearon a partir de datos al inicio y al cabo de 1 hora y 24 horas del tratamiento, para evaluar el valor de los parámetros hemodinámicos principales con respecto a la capacidad predictiva de la PA, la frecuencia cardíaca y las variables demográficas en estos intervalos. El 22 % de la cohorte necesitó terapia vasodilatadora adicional antes del parto. Estas mujeres tuvieron tasas más altas de hipertensión grave y neonatos más pequeños en edades gestacionales más tempranas. Las mujeres que no respondieron al tratamiento fueron con más frecuencia de raza negra, tuvieron la PA y la resistencia vascular periférica (RVP) más alta, y la frecuencia cardíaca y el gasto cardíaco (GC) más bajos al inicio del tratamiento. Aquellas que necesitaron terapia vasodilatadora mostraron un descenso inicial de la PA y la RVP, que se recuperó al cabo de 24 h, mientras que la PA y la RVP en las que respondieron al labetalol mostraron una disminución constante al cabo de 1 h y de 24 h. El volumen sistólico y el GC no disminuyeron durante la fase aguda del tratamiento en ninguno de los grupos. El mejor modelo para la predicción de la necesidad de vasodilatadores se obtuvo a las 24 h mediante la combinación de la etnia con los cambios longitudinales de la PA y la frecuencia cardíaca. El modelo alcanzó una tasa de detección del 100% para una tasa de falsos positivos del 20% y un área bajo la curva de características operativas del receptor de 0,97. CONCLUSIÓN: Los datos demográficos maternos y los cambios hemodinámicos en la fase aguda de la monoterapia con labetalol constituyen una herramienta poderosa para identificar a las pacientes embarazadas hipertensas con pocas probabilidades de que se les pueda controlar su PA mediante esta terapia y que por lo tanto necesitarán terapia vasodilatadora adicional. : 、(blood pressure,BP),。。,1 h24 h,。 : 134。BP>150/100 mmHgBP>140/90 mmHg。1 h24 hBP。,BP135/85 mmHg。BP,()。logistic(),。1 h24 h,,BP、。 : 22%。。,BP(peripheral vascular resistance,PVR),(cardiac output,CO)。BPPVR,24 h,1 h24 hBPPVR。CO。24hBP。100%,20%,0.97。 : ,BP。. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Association between diabetes and tuberculosis: case-control study.

PubMed

Pereira, Susan Martins; Araújo, Gleide Santos de; Santos, Carlos Antônio de Souza Teles; Oliveira, Maeli Gomes de; Barreto, Maurício Lima

2016-12-22

To test the association between diabetes and tuberculosis. It is a case-control study, matched by age and sex. We included 323 new cases of tuberculosis with positive results for bacilloscopy. The controls were 323 respiratory symptomatic patients with negative bacilloscopy, from the same health services, such as: ambulatory cases from three referral hospitals and six basic health units responsible for the notifications of new cases of tuberculosis in Salvador, Bahia. Data collection occurred between 2008 and 2010. The instruments used were structured interview, including clinical data, capillary blood glucose (during fasting or postprandial), and the CAGE questionnaire for screening of abusive consumption of alcohol. Descriptive, exploratory, and multivariate analysis was performed using conditional logistic regression. The average age of the cases was 38.5 (SD = 14.2) years and of the controls, 38.5 (SD = 14.3) years. Among cases and controls, most subjects (61%) were male. In univariate analysis we found association between the occurrence of diabetes and tuberculosis (OR = 2.37; 95%CI 1.04-5.42), which remained statistically significant after adjustment for potential confounders (OR = 3.12; 95%CI 1.12-7.94). The association between diabetes and tuberculosis can hinder the control of tuberculosis, contributing to the maintainance of the disease burden. The situation demands increasing early detection of diabetes among people with tuberculosis, in an attempt to improve disease control strategies. Testar a associação entre diabetes e tuberculose. Trata-se de estudo caso-controle, pareado por idade e sexo. Foram incluídos 323 casos novos de tuberculose com resultados positivos à baciloscopia. Os controles foram 323 sintomáticos respiratórios com baciloscopia negativa, oriundos dos mesmos serviços de saúde dos casos: ambulatórios de três hospitais de referência e seis unidades básicas de saúde responsáveis pelas notificações dos casos novos de tuberculose em Salvador, Bahia. A coleta de dados ocorreu entre 2008 e 2010. Os instrumentos utilizados foram entrevista estruturada, incluindo dados clínicos, glicemia capilar (em jejum ou pós-prandial) e o questionário CAGE para triagem de consumo abusivo de álcool. Foi realizada análise descritiva, exploratória e multivariada utilizando-se de regressão logística condicional. A média de idade dos casos foi 38,5 (DP = 14,2) anos e dos controles, 38,5 (DP = 14,3) anos. Tanto entre os casos quanto entre os controles, a maioria (61%) dos indivíduos era do sexo masculino. Na análise univariada, houve associação entre ocorrência de diabetes e de tuberculose (OR = 2,37; IC95% 1,04-5,42), que permaneceu estatisticamente significante após ajuste pelos potenciais confundidores (OR = 3,12; IC95% 1,12-7,94). A associação entre diabetes e tuberculose pode dificultar o controle da tuberculose, contribuindo para manutenção da elevada carga da doença. A situação demanda intensificação da detecção precoce de diabetes entre pessoas com tuberculose, na tentativa de maior efetividade das estratégias de controle da doença.

Relationship between Cardiometabolic Parameters and Elevated Resting and Effort Heart Rate in Schoolchildren.

PubMed

Silva, Cristiane Fernanda da; Burgos, Miria Suzana; Silva, Priscila Tatiana da; Burgos, Leandro Tibiriçá; Welser, Letícia; Sehn, Ana Paula; Horta, Jorge André; Mello, Elza Daniel de; Reuter, Cézane Priscila

2017-09-01

Little has been studied on heart rate and its relationship with metabolic disorders. To identify possible association between heart rate (HR) and metabolic disorders in children and adolescents. This cross-sectional study evaluated 2.098 subjects, aged between 7 and 17 years. The variables evaluated were: HR, systolic (SBP) and diastolic blood pressure (DBP), pulse pressure (PP), double-product (DP), myocardial oxygen consumption (mVO2), lipids, glucose and uric acid levels, body mass index (BMI) and waist circumference (WC). The values of HR at rest and effort were divided into quartiles. The association between continuous values of HR and cardiometabolic indicators was tested by linear regression. LDL cholesterol presented a significantly higher mean (p = 0.003) in schoolchildren with resting HR greater or equal to 91 bpm, compared to students with less than 75 bpm. Compared with the quartiles of effort HR, SBP, DBP, glucose and uric acid presented high values when HR was greater or equal than 185 bpm. SBP, glucose and HDL cholesterol demonstrated a significant association with resting HR. Uric acid was observed as a predictor of increased effort HR. Schoolchildren with a higher resting HR have higher mean of LDL cholesterol. For effort HR, there was an increase in blood pressure, glucose and uric acid levels. Uric acid has been shown to be a predictor of elevated effort HR. Pouco se tem estudado sobre frequência cardíaca e suas relações com alterações metabólicas. Verificar se existe associação entre frequência cardíaca e disfunções metabólicas em crianças e adolescentes. Estudo transversal com 2.098 escolares, com idade entre 7 e 17 anos. As variáveis avaliadas foram: frequência cardíaca (FC), pressão arterial sistólica (PAS), diastólica (PAD) e de pulso (PP), duplo-produto (DP), consumo de oxigênio pelo miocárdio (mVO2), perfil lipídico e glicêmico, níveis de ácido úrico, índice de massa corporal (IMC) e circunferência da cintura (CC). Os valores de FC de repouso e esforço foram divididos em quartis. A associação entre os valores contínuos de FC com indicadores cardiometabólicos foi testada por meio da regressão linear. O colesterol LDL apresentou média significativamente superior (p = 0,003) nos escolares com FC de repouso maior ou igual a 91 bpm, em comparação aos escolares que apresentaram menos de 75 bpm. Comparados com os quartis da FC de esforço, a PAS, PAD, glicose e ácido úrico apresentaram valores elevados quando a FC foi igual ou superior a 185 bpm. A PAS, a glicose e o colesterol HDL demonstraram associação significativa com a FC de repouso. Observou-se o ácido úrico como um preditor do aumento da FC de esforço. Escolares com FC de repouso mais elevada apresentam médias superiores de colesterol LDL. Para FC de esforço, observou-se elevação na pressão arterial, nos níveis de glicose e de ácido úrico. O ácido úrico demonstrou ser preditor da elevação da FC de esforço.

Factors associated with disease-specific survival of patients with non-small cell lung cancer.

PubMed

Souza, Mirian Carvalho de; Cruz, Oswaldo Gonçalves; Vasconcelos, Ana Glória Godoi

2016-01-01

Lung cancer is a global public health problem and is associated with high mortality. Lung cancer could be largely avoided by reducing the prevalence of smoking. The objective of this study was to analyze the effects of social, behavioral, and clinical factors on the survival time of patients with non-small cell lung cancer treated at Cancer Hospital I of the José Alencar Gomes da Silva National Cancer Institute, located in the city of Rio de Janeiro, Brazil, between 2000 and 2003. This was a retrospective hospital cohort study involving 1,194 patients. The 60-month disease-specific survival probabilities were calculated with the Kaplan-Meier method for three stage groups. The importance of the studied factors was assessed with a hierarchical theoretical model after adjustment by Cox multiple regression. The estimated 60-month specific-disease lethality rate was 86.0%. The 60-month disease-specific survival probability ranged from 25.0% (stages I/II) to 2.5% (stage IV). The performance status, the intention to treat, and the initial treatment modality were the major prognostic factors identified in the study population. In this cohort of patients, the disease-specific survival probabilities were extremely low. We identified no factors that could be modified after the diagnosis in order to improve survival. Primary prevention, such as reducing the prevalence of smoking, is still the best method to reduce the number of people who will suffer the consequences of lung cancer. O câncer de pulmão é um problema de saúde pública global e é associado a elevada mortalidade. Ele poderia ser evitado em grande parte com a redução da prevalência do tabagismo. O objetivo deste estudo foi analisar os efeitos de fatores sociais, comportamentais e clínicos sobre o tempo de sobrevida de pacientes com câncer de pulmão de células não pequenas atendidos, entre 2000 e 2003, no Hospital do Câncer I do Instituto Nacional de Câncer José Alencar Gomes da Silva, localizado na cidade do Rio de Janeiro. Estudo retrospectivo de coorte hospitalar com 1.194 pacientes. As probabilidades de sobrevida doença-específica em 60 meses foram calculadas com o método de Kaplan-Meier para três grupos de estadiamento. A importância dos fatores estudados foi avaliada por um modelo teórico hierarquizado após o ajuste de modelos de regressão múltipla de Cox. Foi estimada uma taxa de letalidade doença-específica em 60 meses de 86,0%. A probabilidade de sobrevida doença-específica em 60 meses variou de 25,0%, nos estádios iniciais, a 2,5%, no estádio IV. A situação funcional, a intenção e a modalidade do tratamento inicial foram os principais fatores prognósticos identificados na população estudada. As probabilidades de sobrevida doença-específica estimadas na amostra estudada foram muito baixas, e não foram identificados fatores que pudessem ser modificados após o diagnóstico visando uma melhora da sobrevida. A prevenção primária, como a redução da prevalência do tabagismo, ainda é a melhor forma de evitar que mais pessoas sofram as consequências do câncer de pulmão.

Modeling and self-assembly behavior of PEG-PLA-PEG triblock copolymers in aqueous solution

NASA Astrophysics Data System (ADS)

Wu, Xiaohan; Li, Suming; Coumes, Fanny; Darcos, Vincent; Lai Kee Him, Joséphine; Bron, Patrick

2013-09-01

A series of poly(ethylene glycol)-polylactide-poly(ethylene glycol) (PEG-PLA-PEG) triblock copolymers with symmetric or asymmetric chain structures were synthesized by combination of ring-opening polymerization and copper-catalyzed click chemistry. The resulting copolymers were used to prepare self-assembled aggregates by dialysis. Various architectures such as nanotubes, polymersomes and spherical micelles were observed from transmission electron microscopy (TEM), cryo-TEM and atomic force microscopy (AFM) measurements. The formation of diverse aggregates is explained by modeling from the angle of both geometry and thermodynamics. From the angle of geometry, a ``blob'' model based on the Daoud-Cotton model for star polymers is proposed to describe the aggregate structures and structural changes with copolymer composition and molar mass. In fact, the copolymer chains extend in aqueous medium to form single layer polymersomes to minimize the system's free energy if one of the two PEG blocks is short enough. The curvature of polymersomes is dependent on the chain structure of copolymers, especially on the length of PLA blocks. A constant branch number of aggregates (f) is thus required to preserve the morphology of polymersomes. Meanwhile, the aggregation number (Nagg) determined from the thermodynamics of self-assembly is roughly proportional to the total length of polymer chains. Comparing f to Nagg, the aggregates take the form of polymersomes if Nagg ~ f, and change to nanotubes if Nagg > f to conform to the limits from both curvature and aggregation number. The length of nanotubes is mainly determined by the difference between Nagg and f. However, the hollow structure becomes unstable when both PEG segments are too long, and the aggregates eventually collapse to yield spherical micelles. Therefore, this work gives new insights into the self-assembly behavior of PEG-PLA-PEG triblock copolymers in aqueous solution which present great interest for biomedical and pharmaceutical applications.A series of poly(ethylene glycol)-polylactide-poly(ethylene glycol) (PEG-PLA-PEG) triblock copolymers with symmetric or asymmetric chain structures were synthesized by combination of ring-opening polymerization and copper-catalyzed click chemistry. The resulting copolymers were used to prepare self-assembled aggregates by dialysis. Various architectures such as nanotubes, polymersomes and spherical micelles were observed from transmission electron microscopy (TEM), cryo-TEM and atomic force microscopy (AFM) measurements. The formation of diverse aggregates is explained by modeling from the angle of both geometry and thermodynamics. From the angle of geometry, a ``blob'' model based on the Daoud-Cotton model for star polymers is proposed to describe the aggregate structures and structural changes with copolymer composition and molar mass. In fact, the copolymer chains extend in aqueous medium to form single layer polymersomes to minimize the system's free energy if one of the two PEG blocks is short enough. The curvature of polymersomes is dependent on the chain structure of copolymers, especially on the length of PLA blocks. A constant branch number of aggregates (f) is thus required to preserve the morphology of polymersomes. Meanwhile, the aggregation number (Nagg) determined from the thermodynamics of self-assembly is roughly proportional to the total length of polymer chains. Comparing f to Nagg, the aggregates take the form of polymersomes if Nagg ~ f, and change to nanotubes if Nagg > f to conform to the limits from both curvature and aggregation number. The length of nanotubes is mainly determined by the difference between Nagg and f. However, the hollow structure becomes unstable when both PEG segments are too long, and the aggregates eventually collapse to yield spherical micelles. Therefore, this work gives new insights into the self-assembly behavior of PEG-PLA-PEG triblock copolymers in aqueous solution which present great interest for biomedical and pharmaceutical applications. Electronic supplementary information (ESI) available: 1H-NMR, DOSY, FTIR, and GPC measurements, methods and results of the copolymers in PEG-PLA-PEG synthesis. See DOI: 10.1039/c3nr02899b

Tuning the Emission and Quantum Yield of Gold and Silver Nanoclusters Through Ligand Design and Doping

NASA Astrophysics Data System (ADS)

Mishra, Dinesh

Nanoparticles have been extensively studied in the past few decades due to the possibilities they offer in applications ranging from medicine to energy generation. A new class of ultra-small noble metal nanoparticles consisting of tens to hundreds of atoms, commonly known as clusters or nanoclusters, have drawn interest of the research community recently due to their unique optical, electronic and structural properties. Over the past few years, advances have been made in the synthesis of atomically precise noble metal clusters (for example, silver and gold) with distinct optical properties. Their ultra-small size distinguishes them from conventional plasmonic nanoparticles and the properties are very sensitive to the slight variation in the compositon of the cluster, i.e. the number of the metal atoms and/or the nature of the ligands. These clusters are interesting because of their potential applications in field such as sensing, imaging, catalysis, clean energy, photonics, etc. as well as they provide fundamental insight into the evolution of the optical and electronic properties of these clusters. In this project, we explored the strategies to synthesize luminescent metallic clusters of gold and silver and to promote their solubility and stability in aqueous and biological medium. We focused particularly on the thiolate protected clusters due to the higher affinity of gold and silver to sulfur. Lipoic acid (Thioctic acid) is a bio-molecule with a cyclic disulfide ring, which also acts as a chelating ligand. Due to the higher binding affinity of the cyclic disulfide ring to nanocrystal surface, lipoic acid and chemically modified lipoic acid molecules have been widely reported for the synthesis and functionalization of inorganic nanocrystals. Here, we describe the use of bidentate lipoic acid ligands in the one phase growth of luminescent gold and silver nanoclusters. In addition, we have synthesized a new set of monothiol ligands containing PEG and zwitterion for the functionalization of fluorescent clusters. Chapter 1 introduces the fundamental properties of metallic clusters and the origin of these properties from electronic and structural point of view. The optical properties of ultra-small nanocrystals (<2 nm) in comparison to the plasmonic particles is described. In addition, the variation of optical and structural properties from one metal to another as well as one ligand to another is also compared. Chapter 2 describes the synthesis of ultra-small size gold clusters with different optical emission (ranging from blue to red) using photo-activated LA-PEG ligands. The influence of various factors on the growth of the clusters is also studied. Optical properties of the clusters were studied by UV-visible absorption, PL emission and excitation and time resolved fluorescence spectroscopy. XPS and DOSY NMR were used to characterize the oxidation states and sizes of these clusters. The photo-chemical transformation of LA-PEG ligands to thiols and the effect of various experimental parameters such as solvent, oxygen, ligand functional group and effect of acid are described in chapter 3. Thiol yield percentage was quantified using ellman assay. Chapter 4 describes the one phase aqueous synthesis of Ag29 clusters capped with bidentate dihydrolipoic acid (DHLA). We also describe the drastic enhancement of the PL intensity upon gold doping of the Ag29 clusters. Optical properties along with the size characterization by electrospray ionization mass spectrometry is also described. We further describe the growth of these clusters using DHLA-PEG molecules. Chapter 5 describes the synthesis of highly fluorescent Au25-xAgx clusters stabilized with two types of ligands (triphenylphosphine and thiols). We designed a set of monothiolate ligands appended with PEG and zwitterionic moieties. This approach allows to prepare water soluble and stable metallic clusters with enhanced photoluminescence and well defined optical properties. Chapter 6 is the overall summary of our findings and prospects and outlook.

Synthesis, characterization and functionalization of silicon nanoparticle based hybrid nanomaterials for photovoltaic and biological applications

NASA Astrophysics Data System (ADS)

Xu, Zejing

Silicon nanoparticles are attractive candidates for biological, photovoltaic and energy storage applications due to their size dependent optoelectronic properties. These include tunable light emission, high brightness, and stability against photo-bleaching relative to organic dyes (see Chapter 1). The preparation and characterization of silicon nanoparticle based hybrid nanomaterials and their relevance to photovoltaic and biological applications are described. The surface-passivated silicon nanoparticles were produced in one step from the reactive high-energy ball milling (RHEBM) of silicon wafers with various organic ligands. The surface structure and optical properties of the passivated silicon nanoparticles were systematically characterized. Fast approaches for purifying and at the same time size separating the silicon nanoparticles using a gravity GPC column were developed. The hydrodynamic diameter and size distribution of these size-separated silicon nanoparticles were determined using GPC and Diffusion Ordered NMR Spectroscopy (DOSY) as fast, reliable alternative approaches to TEM. Water soluble silicon nanoparticles were synthesized by grafting PEG polymers onto functionalized silicon nanoparticles with distal alkyne or azide moieties. The surface-functionalized silicon nanoparticles were produced from the reactive high-energy ball milling (RHEBM) of silicon wafers with a mixture of either 5-chloro-1-pentyne in 1-pentyne or 1,7 octadiyne in 1-hexyne to afford air and water stable chloroalkyl or alkynyl terminated nanoparticles, respectively. Nanoparticles with the ω-chloroalkyl substituents were easily converted to ω-azidoalkyl groups through the reaction of the silicon nanoparticles with sodium azide in DMF. The azido terminated nanoparticles were then grafted with monoalkynyl-PEG polymers using a copper catalyzed alkyne-azide cycloaddition (CuAAC) reaction to afford core-shell silicon nanoparticles with a covalently attached PEG shell. Covalently linked silicon nanoparticle clusters were synthesized via the CuAAC "click" reaction of functional silicon nanoparticles with α,ω-functional PEG polymers of various lengths. Dynamic light scattering studies show that the flexible globular nanoparticle arrays undergo a solvent dependent change in volume (ethanol> dichloromethane> toluene) similar in behavior to hydrogel nanocomposites. A novel light-harvesting complex and artificial photosynthetic material based on silicon nanoparticles was designed and synthesized. Silicon nanoparticles were used as nanoscaffolds for organizing the porphyrins to form light-harvesting complexes thereby enhancing the light absorption of the system. The energy transfer from silicon nanoparticles to porphyrin acceptors was investigated by both steady-state and time-resolved fluorescence spectroscopy. The energy transfer efficiency depended on the donor-acceptor ratio and the distance between the nanoparticle and the porphyrin ring. The addition of C60 resulted in the formation of silicon nanoparticle-porphyrin-fullerene nanoclusters which led to charge separation upon irradiation of the porphyrin ring. The electron-transfer process between the porphyrin and fullerene was investigated by femto-second transient absorption spectroscopy. Finally, the water soluble silicon nanoparticles were used as nanocarriers in photodynamic therapeutic application, in which can selectively deliver porphyrins into human embryonic kidney 293T (HEK293T) cells. In particular, the PEGylated alkynyl-porphyrins were conjugated onto the azido-terminated silicon nanoparticles via a CuAAC "click" reaction. The resultant PEGylated porphyrin grafted silicon nanoparticles have diameters around 13.5 +/- 3.8 nm. The cryo-TEM and conventional TEM analysis proved that the PEGylated porphyrin grafted silicon nanoparticle could form the micelle-like structures at higher concentration in water via self-assembly. The UV-Vis absorption analysis demonstrated that the silicon nanoparticle could reduce the porphyrin aggregation in water which can reduce the photophysical activity of porphyrin. In addition, the nanoparticle complex was capable of producing singlet oxygen when the porphyrin units were excited by light. The cell studies demonstrated that the silicon nanoparticle could deliver the porphyrin drugs into HEK293T cells and accumulate in the mitochondria where the porphyrin could serve as an efficient photosensitizer to kill the cells via mitochondrial apoptotic pathway.

Identification of duck plague virus by polymerase chain reaction

USGS Publications Warehouse

Hansen, W.R.; Brown, Sean E.; Nashold, S.W.; Knudson, D.L.

1999-01-01

A polymerase chain reaction (PCR) assay was developed for detecting duck plague virus. A 765-bp EcoRI fragment cloned from the genome of the duck plague vaccine (DP-VAC) virus was sequenced for PCR primer development. The fragment sequence was found by GenBank alignment searches to be similar to the 3a?? ends of an undefined open reading frame and the gene for DNA polymerase protein in other herpesviruses. Three of four primer sets were found to be specific for the DP-VAC virus and 100% (7/7) of field isolates but did not amplify DNA from inclusion body disease of cranes virus. The specificity of one primer set was tested with genome templates from other avian herpesviruses, including those from a golden eagle, bald eagle, great horned owl, snowy owl, peregrine falcon, prairie falcon, pigeon, psittacine, and chicken (infectious laryngotracheitis), but amplicons were not produced. Hence, this PCR test is highly specific for duck plague virus DNA. Two primer sets were able to detect 1 fg of DNA from the duck plague vaccine strain, equivalent to five genome copies. In addition, the ratio of tissue culture infectious doses to genome copies of duck plague vaccine virus from infected duck embryo cells was determined to be 1:100, making the PCR assay 20 times more sensitive than tissue culture for detecting duck plague virus. The speed, sensitivity, and specificity of this PCR provide a greatly improved diagnostic and research tool for studying the epizootiology of duck plague. /// Se desarroll?? una prueba de reacci??n en cadena por la polimerasa para detectar el virus de la peste del pato. Un fragmento EcoRI de 765 pares de bases clonado del genoma del virus vacunal de la peste del pato fue secuenciado para la obtenci??n de los iniciadores de la prueba de la reacci??n en cadena por la polimerasa. En investigaciones de alineaci??n en el banco de genes ('GenBank') se encontr?? que la secuencia del fragmento era similar a los extremos 3a?? de un marco de lectura abierto indefinido y al gen para la proteina de la DNA polimerasa en otros virus herpes. Se encontraron tres o cuatro grupos de iniciadores especificos para el virus vacunal y para el 100% (7/7) de los a??slamientos de campo, pero no amplificaron el DNA del virus de hepatitis por cuerpos de inclusi??n de grullas. Se analiz?? la especificidad de un primer juego de iniciadores con moldes del genoma de otros virus herpes aviares, incluyendo el ?!guila dorada, ?!guila de cabeza blanca, lechuza de cuernos grandes, lechuza blanca, halc??n peregrino, palomas, aves psit?!cidas y pollos (virus de laringotraqueitis infecciosa), pero no se produjeron los productos finales. Por lo tanto, esta prueba de reacci??n en cadena por la polimerasa es altamente especifica para el DNA del virus. Dos grupos de iniciadores fueron capaces de detectar un fragmento de DNA de la cepa vacunal equivalente a cinco copias del genoma. Adem?!s, se determin?? que la proporci??n de la dosis infecciosa en cultivo celular y copias del genoma del virus vacunal de c??lulas de embri??n de pato infectadas era de 10 a 100 respectivamente, haciendo la prueba de la reacci??n en cadena por la polimerasa 20 veces m?!s sensible que el cultivo celular para detectar el virus. La velocidad, sensibilidad y especificidad de la prueba de la reacci??n en cadena por la polimerasa suministra una herramienta de investigaci??n y de diagn??stico altamente mejorada para el estudio de la epizootiolog?-a del virus.

Smoking among female sex workers: prevalence and associated variables.

PubMed

Devóglio, Ligia Lopes; Corrente, José Eduardo; Borgato, Maria Helena; Godoy, Ilda de

2017-01-01

To assess the prevalence of smoking and associated variables in female sex workers (FSWs). This was a quantitative cross-sectional study involving FSWs in the city of Botucatu, Brazil, who completed a sociodemographic questionnaire, including data regarding smoking status, motivational stage of change, and degree of nicotine dependence, as well as the Perceived Stress Scale and the Hospital Anxiety and Depression Scale. We included 83 FSWs. The mean age was 26.8 years. Among the participants, 58 (69.8%) had at least a high school education, only 26 (31.3%) resided in the city of Botucatu, 59 (71.1%) were smokers, 5 (6.0%) were former smokers, 74 (89.2%) regularly consumed alcohol, and 43 (51.8%) used illicit drugs. The majority of the women were classified as having an intermediate stress level, and 51 (61.4%) were classified as having possible or probable anxiety, whereas depression was found to be improbable in 57 (68.7%). The level of nicotine dependence was high among the smokers, the majority of whom showed no intention to quit smoking. Smoking was associated with illicit drug use (p = 0.0271) and with alcohol consumption (p = 0.0001), although not with the levels of stress, anxiety, or depression; nor was the age at smoking initiation associated with the length of time as an FSW (p = 0.4651). The prevalence of smoking among the FSWs evaluated here was much higher than the 8.3% reported for the overall female population of Brazil. Our findings show that FSWs are exposed to various risk factors inherent to their profession. Therefore, harm reduction is an important strategy to be adopted. Avaliar a prevalência de tabagismo e variáveis associadas em mulheres profissionais do sexo (MPS). Estudo de corte transversal quantitativo com MPS na cidade de Botucatu (SP), as quais completaram um questionário sociodemográfico, incluindo informações sobre tabagismo, estágio motivacional para cessação do tabagismo e grau de dependência da nicotina, assim como a Escala de Estresse Percebido e a Escala Hospitalar de Ansiedade e Depressão. Foram incluídas 83 MPS. A média de idade foi de 26,8 anos. Entre as participantes, 58 (69,8%) possuíam pelo menos o ensino médio, apenas 26 (31,3%) residiam em Botucatu, 59 (71,1%) eram fumantes, 5 (6,0%) eram ex-fumantes, 74 (89,2%) faziam uso de bebidas alcoólicas e 43 (51,8%) faziam uso de algum tipo de drogas. A maioria foi classificada com grau de estresse médio, 51 (61,4%) apresentaram nível de ansiedade possível ou provável, e 57 (68,7%) tiveram resultado improvável para depressão. O nível de dependência da nicotina foi elevado entre as fumantes. Dessas, a maioria não tinha intenção de parar de fumar. Houve associações do tabagismo com o consumo de drogas ilícitas (p = 0,0271) e com o uso de bebidas alcoólicas (p < 0,0001); porém, não houve associações do tabagismo com as questões de humor e nem da idade da iniciação tabágica com o tempo que trabalhavam como MPS (p = 0,4651). A prevalência de tabagismo entre as MPS estudadas se mostrou muito elevada quando comparada à da média nacional de mulheres (8,3%). Evidenciou-se que MPS estão expostas a diversos fatores de risco inerentes da própria profissão, sendo a redução de danos uma estratégia importante a ser trabalhada.

Cultural adaptation and validation of the Portuguese version of the Nursing Clinical Facilitators Questionnaire.

PubMed

Frederico-Ferreira, Maria Manuela; Camarneiro, Ana Paula Forte; Loureiro, Cândida Rosalinda Exposto da Costa; Ventura, Maria Clara Amado Apóstolo

2016-08-15

to perform the cultural adaptation to Portuguese of the Nursing Clinical Facilitators Questionnaire (NCFQ), which was designed by the Centre for Learning and Teaching at the University of Technology of Sydney, and to validate this instrument. this methodological study involved the cultural adaptation of the questionnaire by using translation, back-translation, semantic comparison, idiomatic and conceptual equivalence, and validation through validity and reliability analyses and used a sample of 767 students in their second year of the Nursing Program. construct validity had a two-factor solution according to the varimax rotation method. In addition, there was a high overall internal consistency for the questionnaire (Cronbach's alpha of 0.977) and for the factors found (0.966 and 0.952, respectively). the Portuguese version has good psychometric characteristics; therefore, it is adequate to obtain reliable information on the perception of nursing students concerning the type of supervision that is provided in clinical practice, and this version is adequate to improve teaching practices. realizar a adaptação cultural para a língua portuguesa do Nursing Clinical Facilitators Questionnaire (NCFQ) concebido pelo Centre for Learning and Teaching, University of Technology de Sydney e proceder à validação do instrumento. estudo metodológico de adaptação cultural do questionário através de tradução, retroversão, comparação semântica, idiomática e equivalência conceitual, seguido de validação em uma amostra de 767 estudantes do 2º ano do Curso de Licenciatura em Enfermagem, por meio de análise da validade e confiabilidade. a validade de constructo apresenta uma solução bifatorial após rotação varimax. A consistência interna global do questionário é elevada (alfa de Cronbach 0,977), assim como dos fatores encontrados (respectivamente, 0,966 e 0,952). a versão portuguesa apresenta boas características psicométricas, sendo um instrumento válido para obter informação fidedigna acerca da percepção dos estudantes de enfermagem relativamente ao tipo de orientação tida em contexto clínico, revelando-se importante para melhoria das práticas pedagógicas. llevar a cabo la adaptación cultural al portugués del Nursing Clinical Facilitators Questionnaire (NCFQ), diseñado por el Centre for Learning and Teaching, University of Technology Sydney, y validar este instrumento. este estudio metodológico implicó la adaptación cultural del cuestionario usando la traducción, la retrotraducción, la comparación semántica, la equivalencia idiomática y conceptual, y la validación usando una muestra de 767 estudiantes del segundo curso del Programa de Enfermería mediante análisis de validez y de fiabilidad. la validez del constructo presentó una solución bifactorial según el método de rotación Varimax. Además, hubo una consistencia interna total alta para el cuestionario (alfa de Cronbach de 0,977) y para los factores encontrados (de 0,966 y 0,952, respectivamente). la versión en portugués cuenta con buenas características psicométricas y, por lo tanto, es adecuada para obtener información fiable sobre la percepción de los estudiantes de enfermería sobre el tipo de supervisión proporcionada en la práctica clínica, y esta versión es adecuada para la mejora de las prácticas pedagógicas.

Risk factors for cardiovascular disease in patients with COPD: mild-to-moderate COPD versus severe-to-very severe COPD.

PubMed

Caram, Laura Miranda de Oliveira; Ferrari, Renata; Naves, Cristiane Roberta; Coelho, Liana Sousa; Vale, Simone Alves do; Tanni, Suzana Erico; Godoy, Irma

2016-01-01

To assess and compare the prevalence of comorbidities and risk factors for cardiovascular disease (CVD) in COPD patients according to disease severity. The study included 25 patients with mild-to-moderate COPD (68% male; mean age, 65 ± 8 years; mean FEV1, 73 ± 15% of predicted) and 25 with severe-to-very severe COPD (males, 56%; mean age, 69 ± 9 years; mean FEV1, 40 ± 18% of predicted). Comorbidities were recorded on the basis of data obtained from medical charts and clinical evaluations. Comorbidities were registered on the basis of data obtained from medical charts and clinical evaluations. The Charlson comorbidity index was calculated, and the Hospital Anxiety and Depression Scale (HADS) score was determined. Of the 50 patients evaluated, 38 (76%) had been diagnosed with at least one comorbidity, 21 (42%) having been diagnosed with at least one CVD. Twenty-four patients (48%) had more than one CVD. Eighteen (36%) of the patients were current smokers, 10 (20%) had depression, 7 (14%) had dyslipidemia, and 7 (14%) had diabetes mellitus. Current smoking, depression, and dyslipidemia were more prevalent among the patients with mild-to-moderate COPD than among those with severe-to-very severe COPD (p < 0.001, p = 0.008, and p = 0.02, respectively). The prevalence of high blood pressure, diabetes mellitus, alcoholism, ischemic heart disease, and chronic heart failure was comparable between the two groups. The Charlson comorbidity index and HADS scores did not differ between the groups. Comorbidities are highly prevalent in COPD, regardless of its severity. Certain risk factors for CVD, themselves classified as diseases (including smoking, dyslipidemia, and depression), appear to be more prevalent in patients with mild-to-moderate COPD. Avaliar e comparar a prevalência de comorbidades e de fatores de risco de doença cardiovascular (DCV) em pacientes com DPOC de acordo com a gravidade da doença. O estudo incluiu 25 pacientes com DPOC leve/moderada (homens: 68%; média de idade: 65 ± 8 anos; média de VEF1: 73 ± 15% do previsto) e 25 com DPOC grave/muito grave (homens: 56%; média de idade: 69 ± 9 anos; média de VEF1, 40 ± 18% do previsto). As comorbidades foram registradas com base nos dados dos prontuários médicos e avaliações clínicas. O índice de comorbidades de Charlson foi calculado, e a pontuação na Hospital Anxiety and Depression Scale (HADS) foi determinada. Dos 50 pacientes avaliados, 38 (76%) receberam diagnóstico de pelo menos uma comorbidade, sendo que 21 (42%) receberam diagnóstico de pelo menos uma DCV. Vinte e quatro pacientes (48%) apresentavam mais de uma DCV. Dezoito pacientes (36%) eram fumantes, 10 (20%) tinham depressão, 7 (14%) apresentavam dislipidemia, e 7 (14%) tinham diabetes mellitus. Tabagismo atual, depressão e dislipidemia foram mais prevalentes nos pacientes com DPOC leve/moderada que naqueles com DPOC grave/muito grave (p < 0,001, p = 0,008 e p = 0,02, respectivamente). A prevalência de pressão arterial elevada, diabetes mellitus, alcoolismo, doença isquêmica do coração e insuficiência cardíaca crônica foi semelhante nos dois grupos. O índice de comorbidades de Charlson e a pontuação na HADS não diferiram entre os grupos. Comorbidades são muito prevalentes na DPOC, independentemente da gravidade da doença. Certos fatores de risco de DCV, eles próprios considerados doenças (incluindo tabagismo, dislipidemia e depressão), parecem ser mais prevalentes nos pacientes com DPOC leve/moderada.

EXPRESSION OF E-CADHERIN AND WNT PATHWAY PROTEINS BETACATENIN, APC, TCF-4 AND SURVIVIN IN GASTRIC ADENOCARCINOMA: CLINICAL AND PATHOLOGICAL IMPLICATION.

PubMed

Lins, Rodrigo Rego; Oshima, Celina Tizuko Fujiyama; Oliveira, Levindo Alves de; Silva, Marcelo Souza; Mader, Ana Maria Amaral Antonio; Waisberg, Jaques

2016-01-01

Gastric cancer is the fifth most frequent cancer and the third most common cause of cancer-related deaths worldwide.It has been reported that Wnt/ betacatenin pathway is activated in 30-50% of these tumors. However,the deregulation of this pathway has not been fully elucidated. To determine the expression of E-cadherin, betacatenin, APC, TCF-4 and survivin proteins in gastric adenocarcinoma tissues and correlate with clinical and pathological parameters. Seventy-one patients with gastric adenocarcinoma undergoing gastrectomy were enrolled. The expression of E-cadherin, betacatenin, APC, TCF-4 and survivin proteins was detected by immunohistochemistryand related to the clinical and pathological parameters. The expression rates of E-cadherin in the membrane was 3%; betacatenin in the cytoplasm and nucleus were 23,4% and 3,1% respectively; APC in the cytoplasm was 94,6%; TCF-4 in the nucleus was 19,4%; and survivin in the nucleus 93,9%. The expression rate of E-cadherin was correlated with older patients (p=0,007), while betacatenin with tumors <5 cm (p=0,041) and APC with proximal tumors (p=0,047). Moreover, the expression of TCF-4 was significantly higher in the diffuse type (p=0,017) and T4 tumors (p=0,002). The Wnt/betacatenin is not involved in gastric carcinogenesis. However, the high frequency of survivin allows to suggest that other signaling pathways must be involved in the transformation of gastric tissue. O câncer gástrico encontra-se entre as principais neoplasias malignas do mundo sendo o quinto mais incidente e o terceiro em relação ao índice de mortalidade. Acredita-se que a via Wnt/betacatenina esteja ativada em 30-50% desses tumores, porém a desregulação dela ainda não está completamente esclarecida. Avaliar a imunoexpressão das proteínas E-caderina, betacatenina, APC, TCF-4 e survivina em tecidos de adenocarcinoma gástrico e correlacioná-las com as variáveis clínicas dos doentes e anatomopatológicas do tumor. Foram coletados os dados clínicos e anatomopatológicos dos prontuários de 71 doentes com adenocarcinoma gástrico submetidos à gastrectomia. O material obtido na operação foi submetido à análise imunoistoquímica e a frequência da expressão de cada proteína pôde ser analisada de acordo com a sua localização na célula e relacionada com as variáveis clinicopatológicas. A graduação percentualda expressão e da localização das proteínas foi a seguinte: E-caderina em 3% na membrana; betacatenina em 23,4% no citoplasma e 3,1% no núcleo; APC em 94,6% no citoplasma; TCF-4 em19,4% no núcleo; e survivina em 93,9% no núcleo. Houve relação entre expressão da proteína E-caderina com a idade mais avançada (p=0,007); betacatenina com tumores <5 cm de diâmetro (p=0,041);APC com tumores proximais (p=0,047); e TCF-4 com tipo difuso da classificação de Lauren (p=0,017) e com o grau de penetração tumoral (p=0,002). A via Wnt/betacatenina não está envolvida na carcinogênese gástrica. Porém, a frequência elevada de survivina permite sugerir que outras vias sinalizadoras devam estar envolvidas na transformação do tecido gástrico.

Self-perception of oral health in older adults from an urban population in Lisbon, Portugal.

PubMed

Carvalho, Catarina; Manso, Ana Cristina; Escoval, Ana; Salvado, Francisco; Nunes, Carla

2016-08-22

To analyze if the self-perception of oral health in the urban context is associated with sociodemographic factors that interfere in the life quality of oral health. Cross-sectional study with convenience sample of older individuals (65 years old or more) enrolled in the Agrupamento de Centros de Saúde de Lisboa Norte (ACES Lisboa Norte - Health Centers Groupings North Lisbon). The self-perception of oral health and associated life quality was evaluated by the Geriatric Oral Health Assessment Index and the individuals were classified according to sociodemographic characteristics. The internal consistency of the questionnaire was evaluated by Cronbach's alpha (α). Later, we used binary logistic regression models to characterize the factors associated with the self-perception of oral health, considering the sociodemographic variables and the older adults' clinical conditions of oral health and establishing the crude and adjusted (to age) odds ratios and their 90% confidence intervals. A total of 369 older adults participated in this study, with an average age of 74.2 years (SD = 6.75); 62.9% were female. On average, the index was moderated, with tendency to be high: 32.9 (SD = 3.6; 12-36 interval). The Cronbach's alpha was high: 0.805. Age, marital status, and the last dental appointment were the factors significantly associated with self-perception of oral health. The study shows that these individuals have a moderate, with tendency to high, self-perception of oral health. The self-perception of oral health assessment allowed us to identify the main associated sociodemographic factors. This instrument can help guiding planning strategies and oral health promotion directed toward a better life quality for this population group. Analisar se a autopercepção de saúde bucal em contexto urbano está associada aos factores sociodemográficos que interferem na qualidade de vida da saúde bucal. Estudo transversal com amostra de conveniência de indivíduos idosos (65 anos ou mais) inscritos no Agrupamento de Centros de Saúde de Lisboa Norte. A autopercepção da saúde bucal e qualidade de vida associada foi avaliada pelo índice de avaliação da saúde bucal em idosos (Geriatric Oral Health Assessment Index) e os indivíduos foram classificados de acordo com as características sociodemográficas. A consistência interna do questionário foi avaliada por meio do alfa (α) de Cronbach. Posteriormente, foram utilizados modelos de regressão logística binária para caracterizar os factores associados com a autopercepção de saúde bucal considerando as variáveis sociodemográficas e de condições clínicas de saúde bucal dos idosos e determinados os odds ratios bruto e ajustado (à idade) e respectivos intervalos de confiança a 90%. Participaram 369 idosos, com média de idade de 74,2 anos (DP = 6,75); 62,9% eram do sexo feminino. Em média, o índice foi moderado com tendência a elevado: 32,9 (DP = 3,6; intervalo 12-36). O alfa de Cronbach foi elevado: 0,805. A idade, o estado civil e a última consulta de Medicina Dentária foram os factores significativamente associados a autopercepção da saúde bucal. O estudo mostra que esses indivíduos apresentam uma autopercepção de saúde bucal moderada, com tendência a elevada. A avaliação da autopercepção da saúde bucal permitiu identificar os principais factores sociodemográficos associados. Este instrumento pode contribuir para orientar as estratégias de planejamento e promoção da saúde bucal direcionadas para uma melhor qualidade de vida deste grupo populacional.

Evaluation of thermochemical biomass conversion in fluidized bed =

NASA Astrophysics Data System (ADS)

Neves, Daniel dos Santos Felix das

Dado o aumento acelerado dos precos dos combustiveis fosseis e as incertezas quanto a sua disponibilidade futura, tem surgido um novo interesse nas tecnologias da biomassa aplicadas a producao de calor, eletricidade ou combustiveis sinteticos. Nao obstante, para a conversao termoquimica de uma particula de biomassa solida concorrem fenomenos bastante complexos que levam, em primeiro lugar, a secagem do combustivel, depois a pirolise e finalmente a combustao ou gasificacao propriamente ditas. Uma descricao relativamente incompleta de alguns desses estagios de conversao constitui ainda um obstaculo ao desenvolvimento das tecnologias que importa ultrapassar. Em particular, a presenca de elevados conteudos de materia volatil na biomassa poe em evidencia o interesse pratico do estudo da pirolise. A importância da pirolise durante a combustao de biomassa foi evidenciada neste trabalho atraves de ensaios realizados num reator piloto de leito fluidizado borbulhante. Verificou-se que o processo ocorre em grande parte a superficie do leito com chamas de difusao devido a libertacao de volateis, o que dificulta o controlo da temperatura do reator acima do leito. No caso da gasificacao de biomassa a pirolise pode inclusivamente determinar a eficiencia quimica do processo. Isso foi mostrado neste trabalho durante ensaios de gasificacao num reator de leito fluidizado de 2MWth, onde um novo metodo de medicao permitiu fechar o balanco de massa ao gasificador e monitorizar o grau de conversao da biomassa. A partir destes resultados tornou-se clara a necessidade de descrever adequadamente a pirolise de biomassa com vista ao projeto e controlo dos processos. Em aplicacoes de engenharia ha particular interesse na estequiometria e propriedades dos principais produtos piroliticos. Neste trabalho procurou-se responder a esta necessidade, inicialmente atraves da estruturacao de dados bibliograficos sobre rendimentos de carbonizado, liquidos piroliticos e gases, assim como composicoes elementares e poderes calorificos. O resultado traduziu-se num conjunto de parâmetros empiricos de interesse pratico que permitiram elucidar o comportamento geral da pirolise de biomassa numa gama ampla de condicoes operatorias. Para alem disso, propos-se um modelo empirico para a composicao dos volateis que pode ser integrado em modelos compreensivos de reatores desde que os parâmetros usados sejam adequados ao combustivel ensaiado. Esta abordagem despoletou um conjunto de ensaios de pirolise com varias biomassas, lenhina e celulose, e temperaturas entre os 600 e 975ºC. Elevadas taxas de aquecimento do combustivel foram alcancadas em reatores laboratoriais de leito fluidizado borbulhante e leito fixo, ao passo que um sistema termo-gravimetrico permitiu estudar o efeito de taxas de aquecimento mais baixas. Os resultados mostram que, em condicoes tipicas de processos de combustao e gasificacao, a quantidade de volateis libertada da biomassa e pouco influenciada pela temperatura do reator mas varia bastante entre combustiveis. Uma analise mais aprofundada deste assunto permitiu mostrar que o rendimento de carbonizado esta intimamente relacionado com o racio O/C do combustivel original, sendo proposto um modelo simples para descrever esta relacao. Embora a quantidade total de volateis libertada seja estabelecida pela composicao da biomassa, a respetiva composicao quimica depende bastante da temperatura do reator. Rendimentos de especies condensaveis (agua e especies orgânicas), CO2 e hidrocarbonetos leves descrevem um maximo relativamente a temperatura para dar lugar a CO e H2 as temperaturas mais altas. Nao obstante, em certas gamas de temperatura, os rendimentos de algumas das principais especies gasosas (e.g. CO, H2, CH4) estao bem correlacionados entre si, o que permitiu desenvolver modelos empiricos que minimizam o efeito das condicoes operatorias e, ao mesmo tempo, realcam o efeito do combustivel na composicao do gas. Em suma, os ensaios de pirolise realizados neste trabalho permitiram constatar que a estequiometria da pirolise de biomassa se relaciona de varias formas com a composicao elementar do combustivel original o que levanta varias possibilidades para a avaliacao e projeto de processos de combustao e gasificacao de biomassa.

Relation of streams, lakes, and wetlands to groundwater flow systems

NASA Astrophysics Data System (ADS)

Winter, Thomas C.

Surface-water bodies are integral parts of groundwater flow systems. Groundwater interacts with surface water in nearly all landscapes, ranging from small streams, lakes, and wetlands in headwater areas to major river valleys and seacoasts. Although it generally is assumed that topographically high areas are groundwater recharge areas and topographically low areas are groundwater discharge areas, this is true primarily for regional flow systems. The superposition of local flow systems associated with surface-water bodies on this regional framework results in complex interactions between groundwater and surface water in all landscapes, regardless of regional topographic position. Hydrologic processes associated with the surface-water bodies themselves, such as seasonally high surface-water levels and evaporation and transpiration of groundwater from around the perimeter of surface-water bodies, are a major cause of the complex and seasonally dynamic groundwater flow fields associated with surface water. These processes have been documented at research sites in glacial, dune, coastal, mantled karst, and riverine terrains. Résumé Les eaux de surface sont parties intégrantes des systèmes aquifères. Les eaux souterraines interagissent avec les eaux de surface dans presque tous les types d'environnements, depuis les petits ruisseaux, les lacs et les zones humides jusqu'aux bassins versants des vallées des grands fleuves et aux lignes de côte. Il est en général admis que les zones topographiquement hautes sont des lieux de recharge des aquifères et les zones basses des lieux de décharge, ce qui est le cas des grands systèmes aquifères régionaux. La superposition de systèmes locaux, associés à des eaux de surface, à l'organisation régionale d'écoulements souterrains résulte d'interactions complexes entre les eaux souterraines et les eaux de surface dans tous les environnements, quelle que soit la situation topographique régionale. Les processus hydrologiques associés aux eaux de surface elles-mêmes, tels que des niveaux d'eau de surface saisonnièrement hauts et l'évaporation et la transpiration de l'eau souterraine à la périphérie des eaux de surface, sont les causes essentielles de la dynamique complexe et saisonnière des nappes associées aux eaux de surface. Ces processus ont été mis en évidence sur des sites de recherche dans des formations glaciaires, dunaires, littorales, fluviales et de karst couvert. Resumen Los cuerpos de aguas superficiales son partes integrales de los sistemas de flujo subterráneo. El agua subterránea interactúa con la superficial en prácticamente todo tipo de paisajes, desde pequeños torrentes, lagos y humedales, hasta grandes valles fluviales y costas. Aunque se suele asumir que las áreas topográficamente elevadas son zonas de recarga de aguas subterráneas, mientras las áreas topográficamente más bajas lo son de descarga, esto es cierto básicamente para los sistemas de flujo regional. Al superponer los sistemas de flujo local, asociados a los cuerpos de agua superficial, a las condiciones regionales, resultan interacciones complejas, y esto ocurre independientemente de su posición topográfica. Los procesos hidrológicos asociados con los propios cuerpos de agua superficial, como los niveles superficiales máximos estacionales y la evapotranspiración de agua subterránea en los perímetros de cuerpos superficiales, son una de las principales causas de la complejidad y de las variaciones dinámicas de las interacciones entre aguas subterráneas y superficiales. Estos procesos se han documentado en distintas zonas investigadas, incluyendo depósitos glaciares, dunas, áreas costeras, karsts y terrazas fluviales.

Relationship between Resting Heart Rate, Blood Pressure and Pulse Pressure in Adolescents.

PubMed

Christofaro, Diego Giulliano Destro; Casonatto, Juliano; Vanderlei, Luiz Carlos Marques; Cucato, Gabriel Grizzo; Dias, Raphael Mendes Ritti

2017-05-01

High resting heart rate is considered an important factor for increasing mortality chance in adults. However, it remains unclear whether the observed associations would remain after adjustment for confounders in adolescents. To analyze the relationship between resting heart rate, blood pressure and pulse pressure in adolescents of both sexes. A cross-sectional study with 1231 adolescents (716 girls and 515 boys) aged 14-17 years. Heart rate, blood pressure and pulse pressure were evaluated using an oscillometric blood pressure device, validated for this population. Weight and height were measured with an electronic scale and a stadiometer, respectively, and waist circumference with a non-elastic tape. Multivariate analysis using linear regression investigated the relationship between resting heart rate and blood pressure and pulse pressure in boys and girls, controlling for general and abdominal obesity. Higher resting heart rate values were observed in girls (80.1 ± 11.0 beats/min) compared to boys (75.9 ± 12.7 beats/min) (p ≤ 0.001). Resting heart rate was associated with systolic blood pressure in boys (Beta = 0.15 [0.04; 0.26]) and girls (Beta = 0.24 [0.16; 0.33]), with diastolic blood pressure in boys (Beta = 0.50 [0.37; 0.64]) and girls (Beta = 0.41 [0.30; 0.53]), and with pulse pressure in boys (Beta = -0.16 [-0.27; -0.04]). This study demonstrated a relationship between elevated resting heart rate and increased systolic and diastolic blood pressure in both sexes and pulse pressure in boys even after controlling for potential confounders, such as general and abdominal obesity. A frequência cardíaca de repouso é considerada um importante fator de aumento de mortalidade em adultos. Entretanto, ainda é incerto se as associações observadas permanecem após ajuste para fatores de confusão em adolescentes. Analisar a relação entre frequência cardíaca de repouso, pressão arterial e pressão de pulso em adolescentes dos dois sexos. Estudo transversal com 1231 adolescentes (716 meninas e 515 meninos, idade de 14-17 anos). Frequência cardíaca, pressão arterial e pressão de pulso foram avaliadas com esfigmomanômetro oscilométrico validado para essa população. Peso e altura foram medidos com balança eletrônica e estadiômetro, respectivamente, e a circunferência abdominal, com uma fita inextensível. Análise multivariada com regressão linear investigou a relação entre frequência cardíaca de repouso, pressão arterial e pressão de pulso em meninos e meninas, controlando para obesidade geral e abdominal. Valores maiores de frequência cardíaca de repouso foram observados em meninas (80,1 ± 11,0 bpm) em comparação a meninos (75,9 ± 12,7 bpm) (p ≤ 0,001). Frequência cardíaca de repouso associou-se com pressão arterial sistólica em meninos [Beta = 0,15 (0,04; 0,26)] e meninas [Beta = 0,24 (0,16; 0,33)], com pressão arterial diastólica em meninos [Beta = 0,50 (0,37; 0,64)] e meninas [Beta = 0,41 (0,30; 0,53)], e com pressão de pulso apenas em meninos [Beta = -0,16 (-0,27; -0,04)]. Este estudo demonstrou a relação da frequência cardíaca de repouso elevada com aumento das pressões arteriais sistólica e diastólica em ambos os sexos e com pressão de pulso em meninos, mesmo após controle para potenciais fatores de confusão, como obesidade geral e abdominal.

Efectos de la irradiación iónica en hielos de moléculas carbonadas

NASA Astrophysics Data System (ADS)

Satorre, M. A.

En Astrofísica podemos encontrar numerosos contextos en los cuales se observan moléculas en estado sólido que, en condiciones estándar de presión y temperatura, se encontrarían como gases o líquidos. Dichas moléculas se denominan hielos y han sido observadas en nubes densas del medio interestelar, en envolturas circumestelares, en satélites del Sistema Solar, en cometas, etc. Los hielos pueden ser alterados en su composición química debido a diversos factores como por ejemplo variaciones de temperatura o aportes energéticos por parte de la irradiación, ya sea tanto de fotones ultravioleta como de iones. Dependiendo del escenario astrofísico que analicemos, unos factores cobran más importancia que otros. Los experimentos de laboratorio muestran el efecto que produce sobre la composición de los hielos la irradiación iónica, en particular sobre los que contenían alguna molécula con átomos de carbono. Dicha composición se analiza con espectroscopía IR en el rango de 2 a ˜ 25μ m. La aplicabilidad de los resultados de los experimentos es distinta dependiendo de la composición química inicial de los hielos, del tipo de ion utilizado y de la dosis total de irradiación. Existen efectos generales de la irradiación sobre la materia en los experimentos de relevancia astrofísica como son: - la formación de nuevas moléculas, que pueden incluir o no el ion incidente; - la progresiva pérdida de hidrógeno (carbonización) cuando irradiamos muestras que originalmente contienen una determinada relación carbono/hidrógeno; - la variación de la temperatura de sublimación que presentan algunos hielos. Esto puede suceder tanto en hielos que estaban presentes antes de la irradiación como en hielos formados por ésta. Se presentará el papel del ion en la formación de nuevas moléculas a partir de las que originalmente se encontraban en el hielo. Al penetrar en él, el ion provoca distintos procesos como rotura de enlaces y excitaciones electrónicas. En la mayor parte de los casos las especies producidas por la rotura del enlace, se recombinan volviendo a formar la molécula original. Sin embargo un pequeño porcentaje es capaz de formar nuevas moléculas. Si el ion queda implantado en el hielo y es reactivo (H+, C+,ldots) podría formar parte de una molécula nueva que incorpora un átomo que inicialmente no se encontraba presente en el hielo. También se presentará un contraejemplo para demostrar que no es posible asegurar que siempre que implantemos un ion reactivo, éste formará parte de nuevas moléculas en la mezcla. También se presentará la formación de nuevas moléculas a partir de la irradiación de hielos de metano, que llevan a la formación de otros compuestos como acetileno, eteno, etano,... en los cuales la relación C/H ha variado. Además de estos compuestos se forma también un residuo carbonoso (refractario) que es estable a temperatura ambiente y cuya composición química no es bien conocida. Por último, el aumento de la temperatura de sublimación es también una consecuencia de la irradiación, aunque la magnitud del aumento depende de la mezcla original y de la irradiación sufrida. Existen moléculas que llegan a variar su temperatura de sublimación en decenas de grados. Para el caso de moléculas carbonadas se forman especies por irradiación que son estables a temperatura ambiente. Con todo ello se muestra que los experimentos de laboratorio pueden ayudarnos a comprender la formación, destrucción y variación de las propiedades físicas de los hielos de interés astrofísico con la irradiación.

The influence of faults in basin-fill deposits on land subsidence, Las Vegas Valley, Nevada, USA

NASA Astrophysics Data System (ADS)

Burbey, Thomas

2002-07-01

The role of horizontal deformation caused by pumping of confined-aquifer systems is recognized as contributing to the development of earth fissures in semiarid regions, including Las Vegas Valley, Nevada. In spite of stabilizing water levels, new earth fissures continue to develop while existing ones continue to lengthen and widen near basin-fill faults. A three-dimensional granular displacement model based on Biot's consolidation theory (Biot, MA, 1941, General theory of three-dimensional consolidation. Jour. Applied Physics 12:155-164) has been used to evaluate the nature of displacement in the vicinity of two vertical faults. The fault was simulated as (1) a low-permeability barrier to horizontal flow, (2) a gap or structural break in the medium, but where groundwater flow is not obstructed, and (3) a combination of conditions (1) and (2). Results indicate that the low-permeability barrier greatly enhances horizontal displacement. The fault plane also represents a location of significant differential vertical subsidence. Large computed strains in the vicinity of the fault may suggest high potential for failure and the development of earth fissures when the fault is assumed to have low permeability. Results using a combination of the two boundaries suggest that potential fissure development may be great at or near the fault plane and that horizontal deformation is likely to play a key role in this development. Résumé. On considère que la déformation horizontale provoquée par un pompage dans un aquifère captif joue un rôle dans le développement des fissures du sol en régions semi-arides, comme la vallée de Las Vegas (Nevada). Malgré des niveaux d'eau stabilisés, de nouvelles fissures du sol continuent de se développer en longueur et en largeur au voisinage de failles dans les bassins sédimentaires. Un modèle de déplacement granulaire tri-dimensionnel, basé sur la théorie de la consolidation de Biot (Biot, M A, 1941, General theory of three-dimensional consolidation. Jour. Applied Physics 12:155-164), a été utilisé pour évaluer la nature du déplacement au voisinage de deux failles verticales. La faille a été simulée comme 1) une barrière de faible perméabilité pour l'écoulement horizontal, 2) une rupture structurale dans le milieu, mais sans obstruction de l'écoulement, et 3) une combinaison des deux précédentes conditions. Les résultats indiquent que la barrière de faible perméabilité favorise fortement le déplacement horizontal. Le plan de faille constitue aussi un lieu de subsidence différentielle verticale significative. Les fortes contraintes calculées au voisinage de la faille laissent penser qu'il existe un fort potentiel de rupture et le développement de fissures du sol quand on suppose que la faille possède une faible perméabilité. Les résultats utilisant une combinaison des deux conditions suggèrent que le développement potentiel de fissures peut être grand sur ou à proximité du plan de faille et que la déformation horizontale joue vraisemblablement un rôle clé dans ce développement. Resumen. Se conoce la contribución que la deformación horizontal causada por el bombeo de sistemas acuíferos confinados tienen en el desarrollo de fisuras en regiones semiáridas, como es el caso del Valle de Las Vegas (Nevada, Estados Unidos de América). A pesar de la estabilización de los niveles, se continúa desarrollando nuevas fisuras, mientras las ya existentes se alargan y ensanchan cerca de las fallas de relleno de cuenca. Se ha utilizado un modelo tridimensional de desplazamiento granular basado en la teoría de consolidación de Biot (Biot, M.A., 1941. General theory of three-dimensional consolidation. J. Applied Physics, 12: 155-164) para evaluar la naturaleza del desplazamiento junto a dos fallas verticales. Se ha simulado cada falla como (1) una barrera de baja permeabilidad al flujo horizontal, (2) un hueco o ruptura estructural en el medio pero sin obstrucción al flujo de aguas subterráneas, y (3) una combinación de las dos condiciones anteriores. Los resultados indican que la barrera de baja permeabilidad incrementa enormemente el desplazamiento horizontal. El plano de falla también representa una situación de subsidencia diferencial vertical significativa. Los valores elevados que se han calculado para la deformación en la proximidad de la falla pueden sugerir que existe un alto potencial de fallo y desarrollo de fisuras cuando se supone que la falla posee una baja permeabilidad. Si se combinan los dos contornos, los resultados sugieren que el desarrollo potencial de fisuras puede ser mayor en o cerca de el plano de falla, y que es probable que la deformación horizontal desempeñe un papel clave en él.

Factors associated with subendocardial ischemia risk in patients on hemodialysis.

PubMed

Silva, Bruno Caldin da; Sanjuan, Adriano; Costa-Hong, Valéria; Reis, Luciene Dos; Graciolli, Fabiana; Consolim-Colombo, Fernanda; Bortolotto, Luiz Aparecido; Moyses, Rosa Maria Affonso; Elias, Rosilene Motta

2016-01-01

Bone metabolism disorder (BMD) and vascular dysfunction contribute to excess cardiovascular mortality observed in hemodialysis patients. Vascular dysfunction, a new marker of atherosclerosis, can play a role in this risk. Even though associated with higher mortality in the general population, such vascular evaluation in patients on hemodialysis has not been extensively studied. In this cross-sectional study, hemodialysis patients were submitted to flow-mediated dilation, subendocardial viability ratio (SEVR) and ejection duration index assessment, in order to estimate the impact of BMD markers on vascular dysfunction. A matched cohort of patients with (n = 16) and without (n = 11) severe secondary hyperparathyroidism (SHPT) was studied. Additionally, time spent under severe SHPT was also evaluated. Patients with severe SHPT had lower SEVR and higher ejection duration index, indicating higher cardiovascular risk. Lower SEVR was also associated to diastolic blood pressure (r = 0.435, p = 0.049), serum 25-Vitamin-D levels (r = 0.479, p = 0.028) and to more time spent under severe secondary hyperparathyroidism (SHPT), defined as time from PTH > 500pg/ml until parathyroidectomy surgery or end of the study (r = -0.642, p = 0.027). In stepwise multiple regression analysis between SEVR and independent variables, lower SEVR was independently associated to lower serum 25-Vitamin-D levels (p = 0.005), female sex (p = 0.012) and more time spent under severe SHPT (p = 0.001) in a model adjusted for age, serum cholesterol, and blood pressure (adjusted r² = 0.545, p = 0.001). Subendocardial perfusion was lower in patients with BMD, reflecting higher cardiovascular risk in this population. Whether early parathyroidectomy in the course of kidney disease could modify such results still deserves further investigation. Distúrbios do metabolismo ósseo (DMO) e alterações da função vascular contribuem para a elevada mortalidade de pacientes em hemodiálise. A disfunção vascular, um novo marcador de aterosclerose, pode contribuir para este risco. Apesar de associada a aumento de mortalidade na população geral, a avaliação de tal disfunção ainda não foi realizada de modo amplo em pacientes em hemodiálise. Neste estudo transversal, pacientes em hemodiálise foram submetidos à avaliação da vasodilatação mediada por fluxo, razão de viabilidade subendocárdica (RVSE) e índice de duração de ejeção, como estimativas de avaliação dos marcadores de DMO sobre disfunção vascular. Uma coorte pareada com (n = 16) e sem (n = 11) hiperparatireoidismo secundário (HPTS) grave foi estudada. Adicionalmente, o tempo transcorrido do diagnóstico de HPTS grave também foi avaliado. Pacientes com HPTS grave apresentaram menores valores de RVSE e maiores valores de índice de duração de ejeção, apontando maior risco cardiovascular. Baixa RVSE também foi associada à pressão arterial diastólica (r = 0,435, p = 0,049), níveis séricos de 25-Vitamina D (r = 0,479, p = 0,028) e maior tempo transcorrido desde diagnóstico de HPTS grave, definido como tempo em que o paciente permaneceu com valores de paratormônio superiores a 500 pg/ml até realização de cirurgia de paratireoidectomia ou término do estudo (r = -0,642, p = 0,027). Em regressão logística stepwise entre RVSE e variáveis independentes, menor RVSE foi independentemente associado a menores valores de 25-Vitamina D (p = 0,005), sexo feminino (p = 0,012) e maior tempo transcorrido desde diagnóstico de HPTS grave (p = 0,001) em um modelo ajustado para idade, colesterol sérico e pressão arterial (r2 ajustado = 0,545, p = 0,001). A perfusão subendocárdica foi menor em pacientes com DMO, refletindo o maior risco cardiovascular nesta população. Investigações adicionais são necessárias para definir se a paratireoidectomia precoce no curso da doença renal crônica poderia interferir neste risco.

FROM COMPLEX EVOLVING TO SIMPLE: CURRENT REVISIONAL AND ENDOSCOPIC PROCEDURES FOLLOWING BARIATRIC SURGERY.

PubMed

Zorron, Ricardo; Galvão-Neto, Manoel Passos; Campos, Josemberg; Branco, Alcides José; Sampaio, José; Junghans, Tido; Bothe, Claudia; Benzing, Christian; Krenzien, Felix

Roux-en-Y gastric bypass (RYGB) is a standard therapy in bariatric surgery. Sleeve gastrectomy and gastric banding, although with good results in the literature, are showing higher rates of treatment failure to reduce obesity-associated morbidity and body weight. Other problems after bariatric may occur, as band erosion, gastroesophageal reflux disease and might be refractory to medication. Therefore, a laparoscopic conversion to a RYGB can be an effective alternative, as long as specific indications for revision are fulfilled. The objective of this study was to analyse own and literature data on revisional bariatric procedures to evaluate best alternatives to current practice. Institutional experience and systematic review from the literature on revisional bariatric surgery. Endoscopic procedures are recently applied to ameliorate failure and complications of bariatric procedures. Therapy failure following RYGB occurs in up to 20%. Transoral outlet reduction is currently an alternative method to reduce the gastrojejunal anastomosis. The diameter and volume of sleeve gastrectomy can enlarge as well, which can be reduced by endoscopic full-thickness sutures longitudinally. Dumping syndrome and severe hypoglycemic episodes (neuroglycopenia) can be present in patients following RYGB. The hypoglycemic episodes have to be evaluated and usually can be treated conventionally. To avoid partial pancreatectomy or conversion to normal anatomy, a new laparoscopic approach with remnant gastric resection and jejunal interposition can be applied in non-responders alternatively. Hypoglycemic episodes are ameliorated while weight loss is sustained. Revisional and endoscopic procedures following bariatric surgery in patients with collateral symptomatic or treatment failure can be applied. Conventional non-surgical approaches should have been applied intensively before a revisional surgery will be indicated. Former complex surgical revisional procedures are evolving to less complicated endoscopic solutions. Bypass gástrico em Y-de-Roux (BGYR) é procedimento padrão em cirurgia bariátrica. Gastrectomia vertical e banda gástrica, embora com bons resultados na literatura, estão mostrando taxas mais elevadas de insucesso no tratamento para reduzir a morbidade associada à obesidade e peso corporal. Outros problemas pós-operatórios podem ocorrer, como a erosão da banda, e doença do refluxo gastroesofágico refratária à medicação. Portanto, conversão laparoscópica para BGYR pode ser alternativa eficaz, desde que indicações específicas para a revisão sejam cumpridas. Analisar os nossos dados e os da literatura sobre procedimentos bariátricos revisionais para avaliar melhores alternativas para a prática atual. Foram efetuados experiência institucional e revisão sistemática da literatura sobre cirurgia bariátrica revisional. Procedimentos endoscópicos estão sendo aplicados recentemente para melhorar a falha e complicações de procedimentos bariátricos. Falha terapêutica após BGYR ocorre em até 20%. A redução transoral é atualmente um método alternativo para reduzir a anastomose gastrojejunal. A gastrectomia vertical pode apresentar aumento de volume e do diâmetro do pouch , o qual podem ser reduzidos por meio de sutura total endoscópica longitudinal. Síndrome de dumping e episódios de hipoglicemia grave (neuroglicopenia) podem estar presentes nos pacientes com BGYR. Os episódios hipoglicêmicos devem ser avaliados e geralmente podem ser tratados convencionalmente. Para evitar pancreatectomia parcial ou conversão à anatomia normal, uma nova abordagem laparoscópica com ressecção do remanescente gástrico e interposição de jejuno, pode ser aplicada como alternativa em não-respondedores. Episódios de hipoglicemia melhoram, enquanto a perda de peso é mantida. Procedimentos revisionais endoscópicos podem ser aplicados após cirurgia bariátrica em pacientes com sintomas colaterais ou na falha do tratamento. Abordagens convencionais não-cirúrgicas devem ser aplicadas intensivamente antes que uma operação revisional seja indicada. Antigos procedimentos cirúrgicos revisionais complexos estão evoluindo para soluções endoscópicas menos complicadas.

Sleep-disordered breathing in patients with COPD and mild hypoxemia: prevalence and predictive variables.

PubMed

Silva, José Laerte Rodrigues; Conde, Marcus Barreto; Corrêa, Krislainy de Sousa; Rabahi, Helena; Rocha, Arthur Alves; Rabahi, Marcelo Fouad

2017-01-01

To infer the prevalence and variables predictive of isolated nocturnal hypoxemia and obstructive sleep apnea (OSA) in patients with COPD and mild hypoxemia. This was a cross-sectional study involving clinically stable COPD outpatients with mild hypoxemia (oxygen saturation = 90-94%) at a clinical center specializing in respiratory diseases, located in the city of Goiânia, Brazil. The patients underwent clinical evaluation, spirometry, polysomnography, echocardiography, arterial blood gas analysis, six-minute walk test assessment, and chest X-ray. The sample included 64 patients with COPD and mild hypoxemia; 39 (61%) were diagnosed with sleep-disordered breathing (OSA, in 14; and isolated nocturnal hypoxemia, in 25). Correlation analysis showed that PaO2 correlated moderately with mean sleep oxygen saturation (r = 0.45; p = 0.0002), mean rapid eye movement (REM) sleep oxygen saturation (r = 0.43; p = 0.001), and mean non-REM sleep oxygen saturation (r = 0.42; p = 0.001). A cut-off point of PaO2 ≤ 70 mmHg in the arterial blood gas analysis was significantly associated with sleep-disordered breathing (OR = 4.59; 95% CI: 1.54-13.67; p = 0.01). The model showed that, for identifying sleep-disordered breathing, the cut-off point had a specificity of 73.9% (95% CI: 51.6-89.8%), a sensitivity of 63.4% (95% CI: 46.9-77.9%), a positive predictive value of 81.3% (95% CI: 67.7-90.0%), and a negative predictive value of 53.1% (95% CI: 41.4-64.4%), with an area under the ROC curve of 0.69 (95% CI: 0.57-0.80), correctly classifying the observations in 67.2% of the cases. In our sample of patients with COPD and mild hypoxemia, the prevalence of sleep-disordered breathing was high (61%), suggesting that such patients would benefit from sleep studies. Inferir a prevalência e as variáveis preditivas de hipoxemia noturna e apneia obstrutiva do sono (AOS) em pacientes portadores de DPOC com hipoxemia leve. Estudo transversal realizado em pacientes ambulatoriais, clinicamente estáveis, portadores de DPOC e hipoxemia leve (saturação de oxigênio = 90-94%) em um centro clínico especializado no atendimento de doenças respiratórias em Goiânia (GO). Os pacientes foram submetidos à avaliação clínica, espirometria, polissonografia, ecocardiografia, gasometria arterial, teste de caminhada de seis minutos e radiografia de tórax. Foram avaliados 64 pacientes com DPOC e hipoxemia leve, e 39 (61%) apresentaram distúrbios respiratórios do sono (14 com AOS e 25 com hipoxemia noturna isolada). A análise de correlação mostrou moderada correlação da PaO2 com saturação média do sono (r = 0,45; p = 0,0002), saturação média do sono rapid eye movement (REM; r = 0,43; p = 0,001) e saturação média do sono não-REM (r = 0,42; p = 0,001). Um ponto de corte de PaO2 ≤ 70 mmHg (OR = 4,59; IC95%: 1,54-13,67; p = 0,01) na gasometria arterial foi significativamente associada com distúrbios respiratórios do sono. O modelo mostrou que, para identificar distúrbios respiratórios do sono, o ponto de corte teve uma especificidade de 73,9% (IC95%: 51,6-89,8%), uma sensibilidade de 63,4% (IC95%: 46,9-77,9%) e valores preditivos positivo e negativo de 81,3% (IC95%: 67,7-90,0%) e 53,1% (IC95%: 41,4-64,4%), respectivamente. A área sob a curva ROC foi de 0,69 (IC95%: 0,57-0,80), e a proporção de observações corretamente classificadas foi de 67,2% dos casos. A elevada prevalência de distúrbios respiratórios do sono em portadores de DPOC e hipoxemia leve nesta amostra (61%) sugere que esses pacientes podem se beneficiar da realização de estudos do sono.

Depression and health behaviors in Brazilian adults - PNS 2013.

PubMed

Barros, Marilisa Berti de Azevedo; Lima, Margareth Guimarães; Azevedo, Renata Cruz Soares de; Medina, Lhais Barbosa de Paula; Lopes, Claudia de Souza; Menezes, Paulo Rossi; Malta, Deborah Carvalho

2017-06-01

To evaluate the prevalence of health-related behaviors according to presence and type of depression in Brazilian adults. Based on a sample of 49,025 adults (18 to 59 years) from the National Survey on Health 2013 (PNS 2013), we estimated the prevalence of health-related behaviors (smoking; passive smoking; frequent or risky alcohol consumption; leisure time physical activity; time watching TV; and eating pattern indicators), according to the presence of depression (minor and major), evaluated by the Patient Health Questionnaire - 9 (PHQ-9), and the report of depressive mood (in up to seven days or more than seven days) over a two-week period. Prevalence ratios were estimated by Poisson regression. Evaluated by the PHQ-9 scale, 9.7% of the Brazilian adults had depression and 3.9% presented major depression. About 21.0% reported depressive mood and, in 34.9% of them, that feeling has been present for more than seven days. In individuals with major depression (PHQ-9), higher prevalence was found in almost all unhealthy behaviors analyzed, in particular, smoking (PR = 1.65), passive smoking (PR = 1.55), risk alcohol consumption (PR = 1.72), TV for ≥ 5 hours/day (PR = 2.13), consumption of fat meat (PR = 1.43) and soft drink (PR = 1.42). The prevalence ratios tended to be lower in those with minor depression. Similar results were observed in adults with depressive mood. This study detected relevant association between depression and health behaviors, in particular for smoking and physical activity. The associations found with the PHQ were similar to those observed with the application of a single question about depressive mood. Our results indicate the importance of assessing the presence of depression and the frequency and severity of symptoms when implementing actions for the promotion of healthy behaviors. Avaliar a prevalência de comportamentos relacionados à saúde segundo a presença e tipo de depressão em adultos brasileiros. Com base em amostra de 49.025 adultos (18 a 59 anos) da Pesquisa Nacional de Saúde 2013, foram estimadas as prevalências de comportamentos relacionados à saúde (tabagismo, fumo passivo, consumo frequente ou de risco de álcool, atividade física de lazer, horas de TV e indicadores de padrão alimentar), segundo a presença de depressão (menor e maior), avaliada pela escala PHQ-9, e o relato de humor depressivo (em até sete dias ou em mais de sete dias) em um período de duas semanas. Razões de prevalências foram estimadas por meio de regressão de Poisson. Avaliados pela escala PHQ-9, 9,7% dos adultos brasileiros apresentaram depressão, e 3,9%, depressão maior. Cerca de 21,0% relataram humor depressivo e em 34,9% deles esse sentimento esteve presente por mais de sete dias. Nos indivíduos com depressão maior (PHQ-9), foram constatadas prevalências mais elevadas de quase todos os comportamentos não saudáveis analisados, principalmente tabagismo (RP = 1,65), fumo passivo (RP = 1,55), consumo de risco de álcool (RP = 1,72), horas de TV ≥ 5 h/dia (RP = 2,13), consumo de carne gordurosa (RP = 1,43) e refrigerante (RP = 1,42). As razões de prevalência tenderam a ser menores na depressão menor. Resultados similares foram observados nos adultos com humor depressivo. O estudo detectou relevante associação entre depressão e comportamentos de saúde, em especial, para tabagismo e atividade física. As associações encontradas com o uso do PHQ foram similares às observadas com a aplicação de uma única pergunta sobre humor depressivo. Os resultados do estudo sinalizam a importância da avaliação da presença de depressão e da frequência e gravidade dos sintomas quando da implementação de ações para a promoção de comportamentos saudáveis.

Synthesis of interlocked molecules by olefin metathesis

NASA Astrophysics Data System (ADS)

Clark, Paul Gregory

A large body of work in the Grubbs group has focused on the development of functional-group tolerant ruthenium alkylidene catalysts that perform a number of olefin metathesis reactions. These catalysts have seen application in a wide range of fields, including classic total synthesis as well as polymer and materials chemistry. One particular family of compounds, interlocked molecules, has benefitted greatly from these advances in catalyst stability and activity. This thesis describes several elusive and challenging interlocked architectures whose syntheses have been realized through the utilization of different types of ruthenium-catalyzed olefin metathesis reactions. Ring-closing olefin metathesis has enabled the synthesis of a [c2]daisy-chain dimer with the ammonium binding site near the cap of the dimer. A deprotonated DCD possessing such a structural attribute will more forcefully seek to restore coordinating interactions upon reprotonation, enhancing its utility as a synthetic molecular actuator. Dimer functionalization facilitated incorporation into linear polymers, with a 48% size increase of an unbound, extended analogue of the polymer demonstrating slippage of the dimer units. Ongoing work is directed at further materials studies, in particular, exploring the synthesis of macroscopic networks containing the DCD units and analyzing the correlation between molecular-scale extension-contraction manipulations and resulting macro-scale changes. A "clipping" approach to a polycatenated cyclic polymer, a structure that resembles a molecular "charm bracelet", has been described. The use of ring-opening metathesis polymerization of a carbamate monomer in the presence of a chain transfer agent allowed for the synthesis of a linear polymer that was subsequently functionalized and cyclized to the corresponding cyclic analogue. This cyclic polymer was characterized through a variety of techniques, and subjected to further functionalization reactions, affording a cyclic polyammonium scaffold. Diolefin polyether fragments were coordinated and "clipped" around the ammonium sites within the polymer backbone using ring-closing olefin metathesis, giving the molecular "charm bracelet". Confirmation of the interlocked nature of the product was achieved via 1H NMR spectroscopy and two-dimensional diffusion ordered NMR spectroscopy. A simple strategy for a one-pot, multi-component synthesis of polyrotaxanes using acyclic diene metathesis polymerization was developed. The polyrotaxanes were characterized by traditional 1H NMR spectroscopy as well as size exclusion chromatography, and the interlocked topology was confirmed using two-dimension diffusion-ordered NMR spectroscopy. The dynamic, self-correcting nature of the ADMET polymerization was also explored through the equilibration of a capped polyammonium polymer in the presence of dibenzo-24-crown-8 ether and olefin metathesis catalysts. The efficiency and ease with which these mechanically interlocked macromolecules can be assembled should facilitate rapid modulation to achieve versatile polyrotaxane architectures. Flexible, switchable [c2]daisy-chain dimers (DCDs) were synthesized, where the macromer ammonium binding site was adjacent to the crown-type recognition structure and separated from the cap by an alkyl chain. A DCD of this topology is expected to have an extended structure in the bound conformation (when the ammonium was coordinated to the crown). Several different macromer candidates were designed to allow access to DCDs with flexible alkyl chains between the ammonium binding site and the cap, and a number of synthetic routes were explored in an effort to access these challenging materials. While the first generation DCD structure proved to be unstable due to a labile ester linkage, work is continuing toward the development of several cap structures in an effort to replace the ester linkage with an ether linkage, which, in the second generation model systems, has proven much more stable to the acidic and basic conditions necessary to induce switching of the dimeric architecture. One of the efforts in our lab is directed at the synthesis of 18F-labeled nanoparticles to be used as tumor imaging agents in positron emission tomography. We have been working to optimize fluorine incorporation while minimizing NP crosslinking. Because of evidence of NP side-reactions with the potassium carbonate base, we have begun to use potassium benzoate solid-state beads. To analyze the fluorinated NPs, various sorbents were explored. It was found that silica sorbents rapidly reacted and bound to the NPs, while the NPs remained unreactive and mobile on alumina. Further analysis of the NPs has been accomplished using 2D-DOSY NMR spectroscopy. Future work with the NPs will involve a systematic evaluation of the role of water on the extent of fluorination, as well as functionalization of the NPs with Cy5.5 dye for use in studies on eyes to be done in collaboration with researchers at the Mayo Clinic.

Tuberculosis control program in the municipal context: performance evaluation.

PubMed

Arakawa, Tiemi; Magnabosco, Gabriela Tavares; Andrade, Rubia Laine de Paula; Brunello, Maria Eugenia Firmino; Monroe, Aline Aparecida; Ruffino-Netto, Antonio; Scatena, Lucia Marina; Villa, Tereza Cristina Scatena

2017-03-30

The objective of this study is to evaluate the performance of the Tuberculosis Control Program in municipalities of the State of São Paulo. This is a program evaluation research, with ecological design, which uses three non-hierarchical groups of the municipalities of the State of São Paulo according to their performance in relation to operational indicators. We have selected 195 municipalities with at least five new cases of tuberculosis notified in the Notification System of the State of São Paulo and with 20,000 inhabitants or more in 2010. The multiple correspondence analysis was used to identify the association between the groups of different performances, the epidemiological and demographic characteristics, and the characteristics of the health systems of the municipalities. The group with the worst performance showed the highest rates of abandonment (average [avg] = 10.4, standard deviation [sd] = 9.4) and the lowest rates of supervision of Directly Observed Treatment (avg = 6.1, sd = 12.9), and it was associated with low incidence of tuberculosis, high tuberculosis and HIV, small population, high coverage of the Family Health Strategy/Program of Community Health Agents, and being located on the countryside. The group with the best performance presented the highest cure rate (avg = 83.7, sd = 10.5) and the highest rate of cases in Directly Observed Treatment (avg = 83.0, sd = 12.7); the group of regular performance showed regular results for outcome (avg cure = 79.8, sd = 13.2; abandonment avg = 9.5, sd = 8.3) and supervision of the Directly Observed Treatment (avg = 42.8, sd = 18.8). Large population, low coverage of the Family Health Strategy/Program of Community Health Agents, high incidence of tuberculosis and AIDS, and being located on the coast and in metropolitan areas were associated with these groups. The findings highlight the importance of the Directly Observed Treatment in relation to the outcome for treatment and raise reflections on the structural and managerial capacity of municipalities in the implementation of the Tuberculosis Control Program. Avaliar o desempenho do Programa de Controle da Tuberculose em municípios paulistas. Pesquisa de avaliação de serviços, com delineamento ecológico, utilizando três agrupamentos não hierárquicos de municípios paulistas de acordo com seu desempenho em relação a indicadores operacionais. Foram selecionadas 195 cidades com no mínimo cinco casos novos de tuberculose notificados no Sistema de Notificação do Estado de São Paulo e 20.000 habitantes ou mais em 2010. A análise de correspondência múltipla foi utilizada para a identificação da associação entre os grupos de distintos desempenhos e as características epidemiológicas, demográficas e de sistemas de saúde dos municípios. O grupo de pior desempenho apresentou as taxas mais elevadas de abandono (média [md] = 10,4; desvio padrão [dp] = 9,4) e as menores proporções de efetivação de Tratamento Diretamente Observado (md = 6,1; dp = 12,9) e esteve associado à baixa incidência de tuberculose, alta confecção tuberculose e HIV, pequeno porte populacional, alta cobertura de Estratégia Saúde da Família/Programa de Agentes Comunitários em Saúde e localização no interior. O grupo de melhor desempenho apresentou a maior taxa de cura (md = 83,7; dp = 10,5) e a maior proporção de casos em Tratamento Diretamente Observado (md = 83,0; dp = 12,7); enquanto o grupo de desempenho regular mostrou resultados regulares de desfecho (cura: md = 79,8; dp = 13,2; abandono: md = 9,5; dp = 8,3) e de efetivação do Tratamento Diretamente Observado (md = 42,8; dp = 18,8). Grande porte populacional, baixa cobertura de Estratégia Saúde da Família/Programa de Agentes Comunitários em Saúde, alta incidência de tuberculose e aids, e localização no litoral e em áreas metropolitanas estiveram associados com esses grupos. Os achados destacam a importância do Tratamento Diretamente Observado em relação ao desfecho do tratamento e levantam reflexões sobre a capacidade estrutural e gerencial dos municípios na operacionalização do Programa de Controle da Tuberculose.

Spatial characteristics of groundwater temperature in the Ishikari Lowland, Hokkaido, northern Japan: analytical and numerical applications

NASA Astrophysics Data System (ADS)

Dim, J. R.; Sakura, Y.; Fukami, H.; Miyakoshi, A.

2002-03-01

In porous sediments of the Ishikari Lowland, there is a gradual increase in the background geothermal gradient from the Ishikari River (3-4 °C 100 m-1) to the southwest highland area (10 °C 100 m-1). However, the geothermal gradient at shallow depths differs in detail from the background distribution. In spite of convective heat-flow loss generally associated with groundwater flow, heat flow remains high (100 mW m-2) in the recharge area in the southwestern part of the Ishikari basin, which is part of an active geothermal field. In the northeastern part of the lowland, heat flow locally reaches 140 mW m-2, probably due to upward water flow from the deep geothermal field. Between the two areas the heat flow is much lower. To examine the role of hydraulic flow in the distortion of the isotherms in this area, thermal gradient vs. temperature analyses were made, and they helped to define the major components of the groundwater-flow system of the region. Two-dimensional simulation modeling aided in understanding not only the cause of horizontal heat-flow variations in this field but also the contrast between thermal properties of shallow and deep groundwater reservoirs. Résumé. Dans les sédiments poreux des basses terres d'Ishikari, on observe une augmentation graduelle du gradient géothermal général depuis la rivière Ishikari (3-4 °C 100 m-1) vers la zone élevée située au sud-ouest (10 °C 100 m-1). Toutefois, le gradient géothermal aux faibles profondeurs diffère dans le détail de la distribution générale. Malgré la perte de flux de chaleur par convection, généralement associée aux écoulements souterrains, le flux de chaleur reste élevé (100 mW m-2) dans la zone de recharge de la partie sud-ouest du bassin de l'Ishikari, qui appartient à un champ géothermal actif. Dans la partie nord-est des basses terres, le flux de chaleur atteint localement 140 mW m-2, probablement à cause d'un écoulement souterrain ascendant depuis le champ géothermal profond. Entre les deux zones, le flux de chaleur est beaucoup plus faible. Afin de déterminer le rôle du flux d'eau souterraine dans la distorsion des isothermes dans cette zone, des analyses du gradient thermal en fonction de la température ont été réalisées elles ont permis de définir les composantes majeures du système aquifère régional. Une modélisation deux-dimensionnelle pour la simulation a ensuite contribué à la compréhension non seulement de la cause des variations horizontales du flux de chaleur dans cette région, mais également du contraste entre les propriétés des réservoirs superficiel et profond. Resumen. En los sedimentos porosos de las tierras bajas de Ishikari, hay un incremento gradual en el gradiente geotérmico desde el río Ishikari (3-4 °C 100 m-1) hacia la zona elevada del sudoeste (10 °C 100 m-1). Sin embargo, el gradiente geotérmico a profundidades someras difiere de la distribución de fondo. A pesar de las pérdidas por el flujo convectivo de calor asociadas generalmente al flujo de aguas subterráneas, el flujo de calor permanece elevado (100 mW m-2) en el área de recarga, hacia el sudoeste de la cuenca del Ishikari, la cual pertenece a un campo geotérmico activo. Al nordeste de las tierras bajas, el flujo de calor alcanza 140 mW m-2, probablemente por el flujo ascendente de agua procedente del campo geotérmico profundo. Entre ambas áreas, el flujo de calor es mucho menor. Para examinar el papel del flujo hidráulico en la distorsión de las isotermas de esta región, se ha comparado el gradiente térmico con la temperatura, con lo cual se ha podido definir los componentes mayoritarios del sistema de flujo de las aguas subterráneas. El uso de modelos bidimensionales ha servido para comprender no sólo del origen de las variaciones horizontales del flujo de calor en este campo, sino también el contraste entre las propiedades térmicas de los reservorios someros y profundos de aguas subterráneas.

Monitoring artificially stimulated fluid movement in the Cretaceous Dakota aquifer, western Kansas

NASA Astrophysics Data System (ADS)

Macfarlane, Allen; Förster, Andrea; Merriam, Daniel; Schrötter, Jörg; Healey, John

2002-10-01

Aquifer properties can be evaluated by monitoring artificially stimulated fluid movements between wells, if the fluid is heated. Changes in the temperature profile recorded in observation wells indicate the flow path of the heated fluid, which in effect acts as a tracer. A fluid-flow experiment in the Cretaceous Dakota Formation at the Hodgeman County site, west-central Kansas, demonstrated the advantage of using the distributed optical-fiber temperature sensing method for monitoring transient temperature conditions in this hydrological application. The fluid flow in the aquifer was increased by producing water from a pumping well and injecting heated water in an injection well 13 m (43 ft) distant from the pumping well. The time-temperature series data obtained and compared with results from previous pumping tests point to interwell heterogeneity of the aquifer and to a zone in the sandstone aquifer of high hydraulic conductivity. However, the experiment would have allowed further clarification of aquifer heterogeneity and thermal properties if at least one observation well had been present between the injection and production wells. Résumé. Les caractéristiques d'un aquifère peuvent être évaluées en effectuant un suivi des mouvements du fluide stimulés artificiellement entre des puits, si le fluide est chauffé. Les variations de profils de température enregistrés dans les puits d'observation donnent des informations sur les directions d'écoulement du fluide chauffé, qui en fait se comporte comme un traceur. Réalisée dans la formation crétacée de Dakota, sur le site du Comté de Hodgeman (centre-ouest du Kansas), une expérience a démontré l'intérêt d'utiliser la méthode de détection distribuée de température par fibres optiques pour suivre les variations de température dans cette application hydrologique. L'écoulement du fluide dans l'aquifère a été favorisé en extrayant de l'eau par pompage et en injectant de l'eau chaude dans un puits d'injection distant de 13 m du puits de pompage. La chronique de température obtenue et comparée aux résultats d'essais de pompage précédents fait apparaître l'hétérogénéité de l'aquifère entre les puits et l'existence d'une zone de forte conductivité hydraulique dans l'aquifère de grès. Toutefois, l'expérience aurait fourni des éclaircissements supplémentaires sur l'hétérogénéité de l'aquifère et sur ses propriétés thermiques si au moins un puits d'observation avait été placé entre le puits d'injection et le puits de pompage. Resumen. Se puede evaluar las propiedades de un acuífero mediante la observación del movimiento de un fluido, calentado artificialmente, entre pozos. Los cambios registrados en el perfil de temperatura de los pozos de observación indican la trayectoria del fluido calentado, el cual actúa como un trazador. Un experimento de este tipo que se realizó en la formación cretácica de Dakota, en el condado de Hodgeman (porción occidental del centro de Kansas, Estados Unidos de América), demostró la ventaja de utilizar el método del sensor de temperatura con fibra óptica distribuída para medir condiciones transitorias de temperatura en esta aplicación hidrológica. El flujo del fluido en el acuífero aumentó con el bombeo de un pozo y la inyección de agua caliente en otro sondeo, que distaba 13 m (43 pies) del primero. Las series de temperatura obtenidas y comparadas con resultados de ensayos de bombeo previos resaltan la heterogeneidad del acuífero entre ambos pozos, así como la existencia de una zona de elevada conductividad hidráulica en el acuífero de la arenisca. Sin embargo, el experimento habría proporcionado más información sobre la heterogeneidad de la formación y sus propiedades termales si se hubiera dispuesto al menos de un punto de observación entre los pozos de inyección y bombeo.

Contributions of groundwater conditions to soil and water salinization

NASA Astrophysics Data System (ADS)

Salama, Ramsis B.; Otto, Claus J.; Fitzpatrick, Robert W.

Salinization is the process whereby the concentration of dissolved salts in water and soil is increased due to natural or human-induced processes. Water is lost through one or any combination of four main mechanisms: evaporation, evapotranspiration, hydrolysis, and leakage between aquifers. Salinity increases from catchment divides to the valley floors and in the direction of groundwater flow. Salinization is explained by two main chemical models developed by the authors: weathering and deposition. These models are in agreement with the weathering and depositional geological processes that have formed soils and overburden in the catchments. Five soil-change processes in arid and semi-arid climates are associated with waterlogging and water. In all represented cases, groundwater is the main geological agent for transmitting, accumulating, and discharging salt. At a small catchment scale in South and Western Australia, water is lost through evapotranspiration and hydrolysis. Saline groundwater flows along the beds of the streams and is accumulated in paleochannels, which act as a salt repository, and finally discharges in lakes, where most of the saline groundwater is concentrated. In the hummocky terrains of the Northern Great Plains Region, Canada and USA, the localized recharge and discharge scenarios cause salinization to occur mainly in depressions, in conjunction with the formation of saline soils and seepages. On a regional scale within closed basins, this process can create playas or saline lakes. In the continental aquifers of the rift basins of Sudan, salinity increases along the groundwater flow path and forms a saline zone at the distal end. The saline zone in each rift forms a closed ridge, which coincides with the closed trough of the groundwater-level map. The saline body or bodies were formed by evaporation coupled with alkaline-earth carbonate precipitation and dissolution of capillary salts. Résumé La salinisation est le processus par lequel la concentration des sels dissous dans l'eau et les sols s'accroît sous l'effet de processus naturels ou anthropiques. L'eau est perdue par l'une ou l'autre combinaison de quatre principaux mécanismes : l'évaporation, l'évapotranspiration, l'hydrolyse et la drainance entre aquifères. La salinité augmente depuis les limites des bassins jusqu'au fond des vallées et le long des axes d'écoulement souterrain. La salinisation est expliquée au moyen de deux principaux modèles chimiques développés par les auteurs : l'altération et le dépôt. Ces modèles sont en accord avec les processus géologiques d'altération et de dépôt qui ont formé les sols et qui recouvrent les bassins versants. Cinq processus d'évolution de sols sous climats aride et semi-aride sont associés à l'eau et à des formations aquifères. Dans tous les cas présentés, l'eau souterraine est le principal agent géologique qui transporte, accumule et dépose les sels. A l'échelle de petits bassins versants dans le sud et dans l'ouest de l'Australie, l'eau est consommée par évapotranspiration et par hydrolyse. L'eau souterraine salée coule le long des berges de rivières et s'accumule dans des paléochenaux, qui fonctionnent comme des zones de stockage de sels, et finalement s'écoule dans des lacs, où la plupart des eaux salées se concentrent. Dans les formations bosselées des grandes plaines du nord du Canada et des États-Unis, des scénarios d'alimentation et de décharge localisées conduisent la salinisation à se produire surtout dans les dépressions, en association avec la formation de sols et d'infiltrations salins. A l'échelle régionale dans les bassins fermés, ce processus peut être à l'origine de playas ou de lacs salés. Dans les aquifères continentaux des bassins de rift du Soudan, la salinité augmente le long des axes d'écoulement souterrain et forme ainsi une zone saline à leur extrémité. La zone saline de chaque rift constitue une crête, qui coïncide avec le creux piézométrique. Le ou les ensembles salins se sont formés par évaporation couplée à la précipitation d'un carbonate alcalino-terreux et à la dissolution de sels par capillarité. Resumen La salinización es el proceso por el cual la concentración de sales disueltas en el agua o el suelo aumenta por causas naturales o antrópicas. El contenido de agua se reduce por uno o una combinación de los siguientes mecanismos: evaporación, evapotranspiración, hidrólisis y goteo entre acuíferos. La salinidad aumenta en la dirección del flujo subterráneo, desde los puntos de recarga hacia los de descarga. La salinización se puede explicar por dos modelos químicos que se pueden definir como erosión y deposición y que están de acuerdo con los clásicos procesos geológicos que tienen los mismos nombres. Se conocen cinco procesos de salinización de suelos ligados al agua o a la extracción de la misma en climas áridos o semiáridos. En todos los casos que se presentan el agua subterránea es el principal agente geológico de transmisión, acumulación y descarga de sales. A escala de pequeña cuenca, en Australia Occidental y del Sur, el agua se pierde mediante evapotranspiración e hidrólisis. El agua subterránea salina fluye a lo largo de los cauces de los arroyos y se acumula en los paleocanales, que actúan como depósitos, hasta que finalmente descarga en los lagos, donde se acumula la mayor parte de la salinidad. En los hummocks de la Zona Norte de los Grandes Llanos de Canadá y EEUU, la recarga localizada y el tipo de descarga provocan que la salinización tenga lugar fundamentalmente en las depresiones. A escala regional y en cuencas cerradas este mismo mecanismo provoca playas o lagos salinos. En los acuíferos continentales de los rift del Sudán, la salinidad se incrementa a lo largo de las líneas de flujo subterráneo y se concentra en el límite distal. La zona salina en cada rift forma una cresta cerrada que se manifiesta en los mapas piezométricos. El cuerpo o cuerpos salinos se formaron por evaporación, acoplada con la precipitación de carbonatos y la disolución de sales capilares.

Arsenic contamination of groundwater: Mitigation strategies and policies

NASA Astrophysics Data System (ADS)

Alaerts, Guy J.; Khouri, Nadim

Contamination of groundwater by arsenic from natural geochemical sources is at present a most serious challenge in the planning of large-scale use of groundwater for drinking and other purposes. Recent improvements in detection limits of analytical instruments are allowing the correlation of health impacts such as cancer with large concentrations of arsenic in groundwater. However, there are at present no known large-scale technological solutions for the millions of people-mostly rural-who are potentially affected in developing countries. An overall framework of combating natural resource degradation is combined with case studies from Chile, Mexico, Bangladesh and elsewhere to arrive at a set of strategic recommendations for the global, national and local dimensions of the arsenic ``crisis''. The main recommendations include: the need for flexibility in the elaboration of any arsenic mitigation strategy, the improvement and large-scale use of low-cost and participatory groundwater quality testing techniques, the need to maintain consistent use of key lessons learned worldwide in water supply and sanitation and to integrate arsenic as just one other factor in providing a sustainable water supply, and the following of distinct but communicable tracks between arsenic-related developments and enhanced, long-term, sustainable water supplies. La contamination des eaux souterraines par l'arsenic provenant de sources naturelles est actuellement un sujet des plus graves dans l'organisation d'un recours à grande échelle des eaux souterraines pour la boisson et d'autres usages. De récentes améliorations dans les limites de détection des équipements analytiques permettent de corréler les effets sur la santé tels que le cancer à de fortes concentrations en arsenic dans les eaux souterraines. Toutefois, il n'existe pas actuellement de solutions technologiques à grande échelle connues pour des millions de personnes, surtout en zones rurales, qui sont potentiellement affectées dans les pays en développement. Un cadre d'ensemble pour lutter contre la dégradation naturelle des ressources est associé à des études de cas au Chili, au Mexique, au Bangladesh et ailleurs afin d'établir un ensemble de recommandations stratégiques pour les dimensions globale, nationale et locale de la «crise» de l'arsenic. Les principales recommandations sont les suivantes: le besoin d'une flexibilité pour élaborer une stratégie de diminution de l'arsenic, l'amélioration et l'utilisation à grande échelle de techniques peu coûteuses et associant les populations pour tester la qualité de l'eau souterraine, le besoin de maintenir un usage logique des leçons clés acquises de par le monde pour l'alimentation en eau et la santé publique, celui d'intégrer l'arsenic simplement comme un autre facteur pour assurer une alimentation durable en eau, et pour suivre des pistes distinctes mais communicables entre les développements liés à l'arsenic et les alimentations durables en eau mises en valeurs à long terme. La contaminación de las aguas subterráneas con arsénico procedente de fuentes geoquímicas naturales es actualmente uno de los retos principales de la planificación a gran escala de las aguas subterráneas para uso de boca y otros fines. Las recientes mejoras en los límites de detección del instrumental analítico permiten correlacionar impactos en la salud tales como el cáncer con concentraciones elevadas de arsénico en las aguas subterráneas. Sin embargo, a fecha de hoy no existen soluciones tecnológicas de gran escala para millones de personas-población principalmente rural-que están potencialmente afectadas en los países en vías de desarrollo. Se combina un enfoque general para combatir la degradación de los recursos naturales con estudios concretos de Chile, México, Bangladesh y cualquier otro lugar que permita obtener un conjunto de recomendaciones estratégicas para las dimensiones global, nacional y local de la ``crisis'' del arsénico. Las recomendaciones principales incluyen la necesidad de flexibilizar la elaboración de cualquier estrategia de mitigación del arsénico la mejora y uso a gran escala de técnicas de muestreo de las aguas subterráneas que sean económicas y participativas; la necesidad de mantener un uso coherente de las lecciones clave aprendidas a nivel mundial en el suministro y saneamiento del agua y de integrar el arsénico como otro factor más en la consecución de un suministro sustentable de agua; y el seguimiento de trazas distintas pero comunicables entre los desarrollos relacionados con el arsénico y los abastecimientos de agua sustentables a largo plazo.

Groundwater targeting in a hard-rock terrain using fracture-pattern modeling, Niva River basin, Andhra Pradesh, India

NASA Astrophysics Data System (ADS)

Srinivasa Rao, Y.; Reddy, T. V. K.; Nayudu, P. T.

2000-09-01

In hard-rock terrain, due to the lack of primary porosity in the bedrock, joints, fault zones, and weathered zones are the sources for groundwater occurrence and movement. To study the groundwater potential in the hard-rock terrain and drought-prone area in the Niva River basin, southern Andhra Pradesh state, India, Landsat 5 photographic data were used to prepare an integrated hydrogeomorphology map. Larsson's integrated deformation model was applied to identify the various fracture systems, to pinpoint those younger tensile fracture sets that are the main groundwater reservoirs, and to understand the importance of fracture density in groundwater prospecting. N35°-55°E fractures were identified as tensile and N35°-55°W fractures as both tensile and shear in the study area. Apparently, these fractures are the youngest open fractures. Wherever N35°-55°E and N35°-55°W fracture densities are high, weathered-zone thickness is greater, water-table fluctuations are small, and well yields are high. Groundwater-potential zones were delineated and classified as very good, good to very good, moderate to good, and poor. Résumé. Dans les roches de socle, l'absence de porosité primaire dans la roche fait que les fractures, les zones de faille et les zones d'altération sont les sites où l'eau souterraine est présente et s'écoule. Pour étudier le potentiel en eau souterraine dans la région de socle sujette à la sécheresse du bassin de la rivière Niva (sud de l'État d'Andhra Pradesh, Inde), des données photographiques de Landsat 5 ont été utilisées pour préparer une carte hydro-géomorphologique. Le modèle intégré de déformation de Larssons a été mis en œuvre pour identifier les différents systèmes de fractures, pour mettre l'accent sur les ensembles de fractures en extension les plus jeunes qui constituent les principaux réservoirs d'eau souterraine, et pour comprendre l'importance de la densité de fractures pour la prospection de l'eau souterraine. Dans la région étudiée, les fractures N35°-55°E ont été identifiées comme étant en extension, et les fractures N35°-55°W comme étant à la fois en extension et en cisaillement. Ces fractures sont apparemment les fractures ouvertes les plus jeunes. Partout où la densité des fractures N35°-55°E et N35°-55°W est élevée, la zone altérée est plus épaisse, les fluctuations de la nappe sont faibles et les rendements des puits sont forts. Des zones à potentiel en eau souterraine ont ainsi été délimitées et classées en excellent, bon à très bon, assez bon et médiocre. Resumen. Las zonas de fracturación y de meteorización son las que condicionan el flujo de agua subterránea en rocas duras, debido a la falta de porosidad primaria en la matriz rocosa. Se utilizaron cinco conjuntos de datos fotográficos del satélite Landsat con el fin de preparar un mapa integrado hidrogeomorfológico de la cuenca del río Niva, al sur del estado Andhra Pradesh (India). El objetivo era estudiar el potencial de aguas subterráneas en esta región, que es propensa a períodos de sequía, en la que predominan las rocas duras. Se aplicó el modelo de deformación integrado de Larsson a la identificación de los sistemas de fracturación. El propósito era, por un lado, identificar los conjuntos de fracturas de tracción más jóvenes, que desempeñan un papel principal como reservorios de aguas subterráneas. Por otro lado, se quería comprender la importancia de la densidad de fracturación en el desarrollo de las aguas subterráneas. Se identificó una familia de fracturas de tracción con orientación N35°-55°E y otra familia N35°-55°W que contenía tanto bandas de cizalla como fracturas de tracción. Aparentemente, se trataba de las fracturas abiertas más recientes. El espesor de la zona de meteorización es grande cuando la densidad de fracturas de estas dos familias es elevada, hecho que está asociado a fluctuaciones pequeñas del nivel freático y a caudales elevados. Se estableció una clasificación de las aguas subterráneas como zona muy buena, buena-muy buena, moderadamente buena, y regular.

Groundwater and climate change: a sensitivity analysis for the Grand Forks aquifer, southern British Columbia, Canada

NASA Astrophysics Data System (ADS)

Allen, D. M.; Mackie, D. C.; Wei, M.

The Grand Forks aquifer, located in south-central British Columbia, Canada was used as a case study area for modeling the sensitivity of an aquifer to changes in recharge and river stage consistent with projected climate-change scenarios for the region. Results suggest that variations in recharge to the aquifer under the different climate-change scenarios, modeled under steady-state conditions, have a much smaller impact on the groundwater system than changes in river-stage elevation of the Kettle and Granby Rivers, which flow through the valley. All simulations showed relatively small changes in the overall configuration of the water table and general direction of groundwater flow. High-recharge and low-recharge simulations resulted in approximately a +0.05 m increase and a -0.025 m decrease, respectively, in water-table elevations throughout the aquifer. Simulated changes in river-stage elevation, to reflect higher-than-peak-flow levels (by 20 and 50%), resulted in average changes in the water-table elevation of 2.72 and 3.45 m, respectively. Simulated changes in river-stage elevation, to reflect lower-than-baseflow levels (by 20 and 50%), resulted in average changes in the water-table elevation of -0.48 and -2.10 m, respectively. Current observed water-table elevations in the valley are consistent with an average river-stage elevation (between current baseflow and peak-flow stages). L'aquifère de Grand Forks, situé en Colombie britannique (Canada), a été utilisé comme zone d'étude pour modéliser la sensibilité d'un aquifère à des modifications de la recharge et du niveau de la rivière, correspondant à des scénarios envisagés de changement climatique dans cette région. Les résultats font apparaître que les variations de recharge de l'aquifère pour différents scénarios de changement climatique, modélisées pour des conditions de régime permanent, ont un impact sur le système aquifère beaucoup plus faible que les changements du niveau des rivières Kettle et Granby, qui coulent dans la vallée. Toutes les simulations ont montré des différences relativement faibles dans la configuration d'ensemble de la nappe et dans la direction générale des écoulements. Des simulations de conditions de recharge forte et de recharge faible produisent respectivement une remontée de 0,05 m et un abaissement de 0,025 m, approximativement, des cotes de la nappe pour l'ensemble de l'aquifère. Des changements simulés de la cote du niveau de la rivière, pour refléter des niveaux plus hauts que ceux des pics de crues (de 20 et de 50%), produisent respectivement des remontées de la nappe de 2,72 et 3,45 m en moyenne. Des changements simulés de l'altitude du niveau de la rivière, pour refléter des niveaux plus bas que ceux de basses eaux (de 20 et de 50%), produisent respectivement des abaissements de la nappe de 0,48 et 2,10 m en moyenne. Les altitudes courantes observées de la nappe dans la vallée sont cohérentes avec une cote moyenne du niveau de la rivière (entre les niveaux courants de basses eaux et de crues). El acuífero de los Grand Forks, situado al sur de la Columbia Británica central (Canadá) ha sido utilizado como lugar de estudio para modelar la sensibilidad de un acuífero a los cambios en la recarga y el caudal de los ríos de acuerdo con escenarios previstos de cambio climático en la región. Los resultados sugieren que las variaciones en la recarga al acuífero bajo los diversos escenarios, que han sido modelados en régimen estacionario, tienen un impacto mucho menor en las aguas subterráneas que los cambios en el caudal de los ríos Kettle y Granby, que discurren por el valle. Todas las simulaciones muestran diferencias relativamente pequeñas en la configuración regional de los niveles freáticos y en la dirección general del flujo subterráneo. Las simulaciones de recarga elevada y baja causan un incremento de 0,05 m y un decremento de 0,025 m, respectivamente, en los niveles del acuífero. Los cambios de la elevación del río, simulados para reflejar niveles de flujo mayores que los valores pico (en un 20% y un 50%) resultan en cambios medios de los niveles del acuífero de 2,72 m y 3,45 m, respectivamente. Los cambios simulados en la elevación del río para flujos inferiores al caudal de base (en un 20% y en un 50%) provocan descensos en los niveles de 0,48 y 2,10 m, respectivamente. Los niveles actuales del acuífero en el valle son coherentes con una elevación media del nivel en el río (entre el caudal de base actual y los picos de caudal).

Use and abuse of the urban groundwater resource: Implications for a new management strategy

NASA Astrophysics Data System (ADS)

Drangert, J.-O.; Cronin, A. A.

Various human activities threaten the groundwater quality and resource under urban areas, and yet residents increasingly depend on it for their livelihood. The anticipated expansion of the world's urban population from 3 to 6 billion in the coming 50 years does not only pose a large water management threat but also provides an opportunity to conserve groundwater in a better way than up to now. The authors argue for a new way to manage urban activities in order to conserve the precious groundwater resource. The focus is on the quality of the discharged water after use in households. Restrictions on what is added to water while using it, e.g. detergents, excreta, paint residues, oils, and pharmaceuticals, are important to simplify the treatment and reuse of used water. Avoiding mixing different wastewater flows has the same positive effect. If increased volumes of wastewater can be treated and reused, the demand on the groundwater resource is reduced, as also occurs with demand management measures. Reduced discharge of polluted water to the environment from households and utilities also conserves the quality of groundwater and reduces sophisticated treatment costs. L'urbanisation conduit à une demande élevée et concentrée d'eau de qualité adéquate, accompagnée du rejet d'importants volumes correspondants d'eaux usées. La nourriture est importée dans les villes tandis que les micro-organismes et les nutriments provenant des excrétas humains sont rejetés dans les rivières, les lacs et aussi les eaux souterraines. De plus, une large gamme de biens de consommation est évacuée par les égouts. Les créances environnementales, c'est-à-dire l'appauvrissement des conditions environnementales qui demandera des apports humains et économiques pour la réhabilitation, sont habituelles dans toutes les villes, et pas seulement dans l'hémisphère sud, comme cela est indiqué dans le rapport sur l'alimentation en eau et la santé publique du monde (publié par l'OMS et UNICEF), établissant que la plupart des eaux résiduaires des zones urbaines reste non traitée (65% en Asie, 86% en Amérique latine et 100% en Afrique). La tâche à réaliser pour l'homme est de protéger les ressources en eau souterraine en sorte qu'elle reste disponible pour les habitants des villes dans le futur. Dans les prochaines 50 années, il faut s'attendre à ce que la population urbaine s'accroisse de 3 à 6 milliards de personnes selon les estimations des Nations Unies; aussi il est impératif de ne pas continuer à polluer les eaux souterraines sous les nouvelles zones urbaines en cours de construction. Dans cet article, nous analyserons la qualité des eaux souterraines et leur protection à la lumière des récents changements de politique de l'eau, c'est-à-dire de la gestion de l'alimentation en eau jusqu'à une gestion de la demande et en abordant éventuellement la période de gestion du recyclage. La urbanización lleva a una demanda elevada y concentrada de agua de calidad adecuada, acompañada por el vertido de volúmenes análogamente mayores de aguas residuales. Los alimentos se importan a ciudades donde los microorganismos y nutrientes de los excrementos humanos son descargados a ríos, lagos y, también, aguas subterráneas. Más aún, gran número de los bienes de consumo son eliminados vía las tuberías de las cloacas. Las deudas medioambientales, es decir, el empobrecimiento de las condiciones medioambientales, que requerirán de aportaciones humanas y económicas para rehabilitarlas, son comunes a todas las ciudades, sobretodo en el Hemisferio Sur, donde, según la Valoración Global de Suministro de Agua y Saneamiento (OMS y UNICEF), la mayor parte de las aguas residuales urbanas no son tratadas (65% en Asia, 86% en Latinoamérica, 100% en África). La tarea pendiente consiste en proteger los recursos de aguas subterráneas para que estén disponibles de forma rápida para los habitantes urbanos también el futuro. En los próximos 50 años, se espera que la población urbana aumente de 3,000 a 6,000 millones de personas, según estimaciones de las Naciones Unidas, por lo que es imperativo dejar de contaminar las aguas subterráneas existentes bajo las nuevas áreas urbanas en construcción. En este artículo, se escudriña la calidad de las aguas subterráneas y su protección a la luz de los cambios recientemente introducidos en las políticas del agua, esto es, desde la gestión de los abastecimientos de agua a la gestión de la demanda y, eventualmente, hastaa la gestión de la reutilitzación.

Integrating geophysical and hydrochemical borehole-log measurements to characterize the Chalk aquifer, Berkshire, United Kingdom

NASA Astrophysics Data System (ADS)

Schürch, Marc; Buckley, David

2002-09-01

Geophysical and hydrochemical borehole-logging techniques were integrated to characterize hydraulic and hydrogeochemical properties of the Chalk aquifer at boreholes in Berkshire, UK. The down-hole measurements were made to locate fissures in the chalk, their spatial extent between boreholes, and to determine the groundwater chemical quality of the water-bearing layers. The geophysical borehole logging methods used were caliper, focused resistivity, induction resistivity, gamma ray, fluid temperature, fluid electrical conductivity, impeller and heat-pulse flowmeter, together with borehole wall optical-imaging. A multiparameter data transmitter was used to measure groundwater temperature, electrical conductivity, dissolved oxygen, pH, and redox potential of the borehole fluid down-hole. High permeability developed at the Chalk Rock by groundwater circulation provides the major flow horizon at the Banterwick Barn study site and represents a conduit system that serves as an effective local hydraulic connection between the boreholes. The Chalk Rock includes several lithified solution-ridden layers, hardgrounds, which imply a gap in sedimentation possibly representing an unconformity. Lower groundwater temperature, high dissolved-oxygen content, and flowmeter evidence of preferential groundwater flow in the Chalk Rock indicated rapid groundwater circulation along this horizon. By repeating the logging at different times of the year under changing hydraulic conditions, other water-inflow horizons within the Chalk aquifer were recognized. Résumé. Des techniques géophysiques et hydrochimiques de diagraphies en forage ont été mises en oeuvre pour caractériser les propriétés hydrauliques et hydrogéochimiques de l'aquifère de la craie dans des forages du Berkshire (Grande-Bretagne). Les mesures en descente ont été faites pour localiser les fissures dans la craie et leur développement spatial entre forages, et pour déterminer la qualité de l'eau souterraine des niveaux aquifères. Les méthodes géophysiques utilisées pour les diagraphies en forage étaient le calibrage, la résistivité concentrée, la résistivité par induction, le rayonnement gamma, la température du fluide, la conductivité électrique du fluide, un courantomètre à impulsions et à flux de chaleur, avec une sonde vidéo pour l'examen des parois du forage. Une sonde multiparamètre a été utilisée pour mesurer la température, la conductivité électrique, l'oxygène dissous, le pH et le potentiel redox dans le fluide du forage à la descente. Une forte perméabilité développée dans la craie par les écoulements souterrains forme le principal niveau d'écoulement du site d'étude de Banterwick Barn ; elle est constituée d'un système de conduits qui crée une connexion hydraulique locale efficace entre les forages. Cet horizon est formé de plusieurs niveaux de haut-fonds lithifiés, qui impliquent l'existence d'une lacune de sédimentation susceptible pouvant correspondre à une discordance. Une plus faible température de l'eau souterraine, une plus forte concentration en oxygène dissous, les indications du courantomètre sur un écoulement préférentiel dans la craie indiquent une circulation rapide de l'eau souterraine le long de cet horizon. En répétant les diagraphies à des moments différents de l'année sous des conditions hydrauliques variées, d'autres horizons d'écoulements d'eau dans l'aquifère de la craie ont été reconnus. Resumen. Se ha integrado técnicas geofísicas e hidroquímicas de registro de sondeos para caracterizar las propiedades hidráulicas e hidrogeoquímicas del acuífero de la Creta en perforaciones de Berkshire (Reino Unido). Las medidas en los sondeos tenían como objetivo localizar fisuras en las cretas, así como determinar su extensión espacial entre sondeos y calidad química de las aguas subterráneas. Entre los métodos de testificación geofísica utilizados, se halla el calibre, la resistividad focalizada e inducida, los rayos gamma, la temperatura y la conductividad eléctrica del fluido, impulsores y medidores de flujo en sondeos por pulsos de calor, junto con el televisor óptico en las paredes de los sondeos. Se ha empleado un transmisor multiparamétrico para medir la temperatura, la conductividad eléctrica, el oxígeno disuelto, el pH y el potencial redox de las aguas subterráneas en el sondeo. El horizonte más productivo está asociado a las superficies litificadas ('hardgrounds') de la Creta que han desarrollado una permeabilidad elevada debido a la circulación de las aguas subterráneas identificado en el emplazamiento de Banterwick Barn, representa un sistema de conductos que actúa como conexión hidráulica local efectiva entre los sondeos. La Creta incluye una serie de 'hardgrounds' compactada por migración de fluidos, produciendo un hiato sedimentario que posiblemente representa una inconformidad. La menor temperatura de las aguas subterráneas, junto con un alto contenido de oxígeno disuelto y la evidencia aportada por el medidor de flujo en sondeos respecto a un flujo preferente en la Creta, indican que la circulación de las aguas es rápida en dicho horizonte. Repitiendo la testificación en épocas distintas del año y bajo condiciones hidráulicas diferentes, se ha podido identificar otros niveles productivos en el acuífero de la Creta.

Effects of positive and negative delusional ideation on memory.

PubMed

Sugimori, Eriko; Tanno, Yoshihiko

2010-04-01

We investigated the relationship between levels of delusional ideation (whether positive or negative delusions) and the activation and distortion of memory by using pairs of positive and negative adjectives describing personality traits where those adjectives had similar meanings. We presented one of each pair of adjectives in the learning phase. Immediately after the learning phase in Experiment 1, we asked whether each adjective had been presented. Participants with high (positive or negative) delusional ideation were more likely to indicate that they had learned adjectives that they had not actually learned. This finding suggested that non-learned positive (or negative) adjectives that were associated with learned negative (or positive) adjectives were more likely to be activated in participants prone to positive (or negative) delusional ideation. However, in Experiment 2, two forced-choice tests were conducted immediately after the learning phase. In this context, participants, regardless of their proneness to delusional ideation, could almost always correctly distinguish what had and had not been presented, suggesting that the activation of learned items was still stronger than that for non-learned items in the immediate test. As time passed, the proportion of false alarms for positive or negative adjectives was higher in the two forced-choice tests among those with high proneness to (positive or negative) delusional ideation, suggesting that participants with delusional ideation were increasingly likely to depend on internal conditions for retrieval over time. Nous avons examiné la relation entre les niveaux d'idéation illusoire (qu'elle soit positive ou négative) et l'activation et la distorsion de la mémoire, en utilisant des paires d'adjectifs positifs et négatifs à significations similaires décrivant des traits de personnalité. Nous avons présenté un membre de chaque paire d'adjectifs lors d'une phase d'apprentissage. Dans une première expérience, immédiatement après la phase d'apprentissage, nous avons demandé si chaque adjectif avait été présenté. Les participants ayant un niveau d'idéation illusoire (positive ou négative) élevé étaient plus susceptibles d'indiquer qu'ils avaient appris les adjectifs qu'ils n'avaient pas appris. Ce résultat suggérait que les adjectifs positifs (ou négatifs) non appris qui étaient associés à des adjectifs négatifs (ou positifs) appris étaient plus susceptibles d'être activés chez les participants portés à l'idéation illusoire positive (ou négative). Dans une deuxième expérience, deux tests à choix forcés ont été menés immédiatement après la phase d'apprentissage. Dans ce contexte, les participants, indépendamment de leur tendance à l'idéation illusoire, pouvaient presque toujours distinguer correctement ce qui avait été présenté de ce qui n'avait pas été présenté, suggérant que l'activation des items appris était encore plus forte que celle des items non appris dans le test immédiat. Avec le temps, la proportion de fausses alarmes pour les adjectifs positifs ou négatifs était plus élevée dans les deux tests à choix forcés chez les participants portés à l'idéation illusoire (positive ou négative), ce qui suggère que les participants avec idéation illusoire étaient de plus en plus susceptibles de dépendre de leurs conditions internes lors du rappel à mesure que le temps passait. En este estudio se investigó la relación entre los niveles de ideación delusional (tanto delusiones positivas como negativas) y la activación y distorsión de la memoria a través del uso de pares de adjetivos positivos y negativos que describen rasgos de personalidad. Estos pares de adjetivos tenían significados similares. En la fase de aprendizaje se presentó un miembro de cada par de adjetivos. Inmediatamente después de la fase de aprendizaje se realizó el primer experimento, en el cual se preguntó al participanten si es que se le habían presentado cada uno de los adjetivos. Los participantes con elevada ideación delusiva (positiva o negativa) reportaran con una mayor probabilidad haber aprendido adjetivos que en realidad no se les había presentado. Este hallazgo sugiere que adjetivos positivos (o negativos) no aprendidos que estaban asociados con adjetivos negativos (o positivos) aprendidos, tenían una mayor probabilidad de ser activados en participantes propensos a una ideación delusiva positiva (o negativa). En el segundo experimento se llevaron a cabo inmediatamente después de la fase de aprendizaje dos pruebas de decisión forzada. En este contexto se pudo observar que los participantes a pesar de su tendencia hacia una ideación delusional, lograron distinguir en la mayoría de los casos correctamente entre los adjetivos que les fueron presentado y lo que no. Esto sugiere que la activación de los items aprendidos fue mucho más intensa que la de los items no aprendidos en el test. Sin embargo se pudo observar en los participantes de las dos pruebas de decisión forzada que con el paso del tiempo el porcentaje de falso reconocimiento de adjetivos positivos y negativos fue más elevado entre aquellas personas con una alta tendencia hacia una ideación delusional (positiva o negativa). Esto sugiere que en participantes con ideación delusional el reconocimiento de información a lo largo del tiempo probablemente es muy dependiente de condiciones internas.

Inverse modeling of groundwater flow in the semiarid evaporitic closed basin of Los Monegros, Spain

NASA Astrophysics Data System (ADS)

Samper-Calvete, F. J.; García-Vera, M. A.

Only minor attention has been given in the past to the study of closed-basin hydrogeology in evaporitic environments, because these basins usually contain poor-quality groundwater. The motivation for hydrogeological research in the Los Monegros area in northeastern Spain was the approval in 1986 of a large irrigation project in the Ebre River basin. The irrigation of 60,000 ha is planned, partly in an evaporitic closed basin containing playa lakes. The project has given rise to environmental concerns. The evaluation of the hydrologic impacts of irrigation requires quantifying properly the hydrogeology of the area. With the available information, a conceptual hydrogeological model was formulated that identifies two main aquifers connected through a leaky aquitard. On the basis of the conceptual model, a numerical model was calibrated under steady-state conditions using the method of maximum-likelihood automatic parameter estimation (Carrera and Neuman, 1986a). The calibrated model reproduces the measured hydraulic heads fairly well and is consistent with independent information on groundwater discharge. By the solution of the inverse problem, reliable parameter estimates were obtained. It is concluded that anisotropy plays a major role in some parts of the lower aquifer. The geometric average of model conductivity is almost two orders of magnitude larger than the average conductivity derived from small-scale field tests. This scale effect in hydraulic conductivity is consistent with the findings of Neuman (1994) and Sánchez-Vila et al. (1996). Résumé Dans le passé, on s'est peu intéresséà l'hydrogéologie des bassins fermés en milieu évaporitique, parce que ces bassins possèdent en général de l'eau souterraine de qualité médiocre. L'intérêt porté aux recherches hydrogéologiques dans la région de Los Monegros, dans le nord-est de l'Espagne est dûà l'approbation en 1986 d'un vaste projet d'irrigation dans le bassin de l'Ebre. L'irrigation de 60000 ha a été programmée, en partie dans un bassin évaporitique fermé où existent des lacs de playa. Le projet a fait émergé des préoccupations environnementales. L'évaluation des impacts hydrologiques de l'irrigation implique de quantifier correctement l'hydrogéologie de cette région. A partir des informations disponibles, un modèle hydrogéologique conceptuel a étéétabli il identifie deux aquifères principaux interconnectés par drainance au travers d'un imperméable. Un modèle numérique, établi sur la base de ce modèle conceptuel, a été calibré en conditions de régime permanent, en utilisant la méthode d'estimation automatique du maximum de vraisemblance des paramètres (Carrera and Neuman, 1986a). Le modèle calibré reproduit correctement la piézométrie mesurée et est en accord avec les informations concernant l'écoulement des nappes. La résolution du problème inverse a fourni des estimations acceptables des paramètres. On en a conclu que l'anisotropie joue un rôle essentiel dans certaines parties de l'aquifère inférieur. La moyenne géométrique de la conductivité hydraulique est d'environ deux ordres de grandeur plus élevée que la conductivité hydraulique moyenne obtenue par des essais de terrain à l'échelle locale. Cet effet d'échelle sur la conductivité hydraulique est conforme aux résultats obtenus par Neuman (1994) et Sánchez-Vila et al. (1996). Resumen La hidrogeología de zonas endorreicas en zonas evaporíticas ha recibido muy poca atención en el pasado debido fundamentalmente a que en estas zonas las aguas subterráneas tienen una elevada salinidad debido a la alta solubilidad de sus materiales. El interés por la hidrogeología de la zona de Los Monegros en el noreste de España surgió a raiz de la aprobación en 1986 del proyecto de Los Monegros II en la zona central del valle del Ebro que contempla la puesta en regadío de 60,000 ha, algunas de las cuales se encuentran situadas en la zona endorreica de Los Monegros en la que existen toda una serie de lagunas salinas. La implantación del regadío en esta zona puede alterar el régimen hidrológico de las lagunas, provocar problemas de salinización de suelos y aguas y aumentar la salinidad del río Ebro. Con el fin de evaluar estos efectos se construyó un modelo numérico del flujo subterráneo. Con la información disponible se pueden distinguir dos acuíferos que están conectados mediante un acuitardo. El modelo de flujo se calibró en régimen estacionario utilizando el procedimiento de calibración automática de Carrera y Neuman (1986a) basado en el método de la máxima verosimilitud. El modelo finalmente calibrado es capaz de reproducir los niveles piezométricos medidos y es coherente con los resultados de los balances hidrológicos en las lagunas. La conductividad hidráulica media del modelo es superior en casi dos órdenes de magnitud a la media de las conductividades hidráulicas obtenidas en ensayos de campo a escala local. Este efecto de escala en la conductividad hidráulica es coherente con los resultados de Neuman (1994) y Sánchez-Vila et al. (1996) y confirma que dicho efecto también se observa en medios evaporíticos.

Groundwater-flow modeling in the Yucatan karstic aquifer, Mexico

NASA Astrophysics Data System (ADS)

González-Herrera, Roger; Sánchez-y-Pinto, Ismael; Gamboa-Vargas, José

2002-09-01

The current conceptual model of the unconfined karstic aquifer in the Yucatan Peninsula, Mexico, is that a fresh-water lens floats above denser saline water that penetrates more than 40 km inland. The transmissivity of the aquifer is very high so the hydraulic gradient is very low, ranging from 7-10 mm/km through most of the northern part of the peninsula. The computer modeling program AQUIFER was used to investigate the regional groundwater flow in the aquifer. The karstified zone was modeled using the assumption that it acts hydraulically similar to a granular, porous medium. As part of the calibration, the following hypotheses were tested: (1) karstic features play an important role in the groundwater-flow system; (2) a ring or belt of sinkholes in the area is a manifestation of a zone of high transmissivity that facilitates the channeling of groundwater toward the Gulf of Mexico; and (3) the geologic features in the southern part of Yucatan influence the groundwater-flow system. The model shows that the Sierrita de Ticul fault, in the southwestern part of the study area, acts as a flow barrier and head values decline toward the northeast. The modeling also shows that the regional flow-system dynamics have not been altered despite the large number of pumping wells because the volume of water pumped is small compared with the volume of recharge, and the well-developed karst system of the region has a very high hydraulic conductivity. Résumé. Le modèle conceptuel classique de l'aquifère karstique libre de la péninsule du Yucatan (Mexique) consiste en une lentille d'eau douce flottant sur une eau salée plus dense qui pénètre à plus de 40 km à l'intérieur des terres. La transmissivité de l'aquifère est très élevée, en sorte que le gradient hydraulique est très faible, compris entre 7 et 10 mm/km dans la plus grande partie du nord de la péninsule. Le modèle AQUIFER a été utilisé pour explorer les écoulements souterrains régionaux dans cet aquifère. La zone karstifiée a été modélisée en posant l'hypothèse qu'il fonctionne hydrauliquement comme un milieu poreux granulaire. Au cours de la calibration, les hypothèses suivantes ont été testées: (1) les phénomènes karstiques jouent un rôle important dans le système aquifère, (2) un anneau ou une ceinture de dépressions dans la région est la manifestation d'une zone à forte transmissivité qui permet l'écoulement en conduits de l'eau souterraine en direction du Golfe du Mexique, et (3) la situation géologique dans la partie sud du Yucatan détermine les écoulements souterrains. Le modèle montre que la faille de la Sierrita de Ticul, dans la partie sud-ouest de la région étudiée, joue le rôle de barrière et que les valeurs de la piézométrie décroissent en direction du nord-est. La modélisation montre également que la dynamique du système aquifère à l'échelle régionale n'a pas été modifiée malgré le grand nombre de puits de pompage, parce que le volume pompé est faible en comparaison du volume de recharge; en outre, le réseau karstique très bien développé dans cette région possède une très forte conductivité hydraulique. Resumen. El modelo conceptual actual del acuífero cárstico no confinado de la Península de Yucatán (México) es el de un lentejón de agua dulce flotando sobre agua salada, más densa, la cual penetra más de 40 kilómetros tierra adentro. Debido a la alta conductividad hidráulica del acuífero, existe un gradiente hidráulico muy bajo cuyo rango está entre 7 y 10 milímetros por kilómetro en la porción norte de la península. Se utilizó el código AQUIFER para investigar el sistema de flujo de las aguas subterráneas a escala regional en el acuífero. La zona carstificada se modeló suponiendo que actúa hidráulicamente como un medio poroso granular. Como parte de la calibración, se probaron las siguientes hipótesis: (1) las características cársticas desempeñan un papel importante en el sistema de flujo de agua subterránea (2) un anillo o cinturón de sumideros en el área es una manifestación de una zona de alta transmisividad que conduce las aguas subterráneas hacia el Golfo de México y (3) las propiedades geológicas de la porción sur de Yucatán influyen en el sistema de flujo de agua subterránea. El modelo demostró que la falla de la Sierrita de Ticul, situada en el sudoeste de la zona de estudio, actúa como una barrera al flujo, y que los niveles piezométricos disminuyen hacia el nordeste. La modelación también mostró que la dinámica del sistema de flujo regional no ha sido alterada a pesar de la gran cantidad de captaciones, ya que el volumen extraído es pequeño en comparación con la recarga al acuífero además, el sistema cárstico de la región, bien desarrollado, posee una conductividad hidráulica muy elevada.

The Pliocene Yafo Formation in Israel: Hydrogeologically inert or active?

NASA Astrophysics Data System (ADS)

Avisar, D.; Rosenthal, E.; Shulman, H.; Zilberbrand, M.; Flexer, A.; Kronfeld, J.; Ben Avraham, Z.; Fleischer, L.

For several decades the ``Saqiye beds'' (later renamed Yafo Formation) underlying the Coastal Plain aquifer (Kurkar Group) aquifer of Israel, were regarded as an extremely thick, tectonically undisturbed, and absolutely impervious aquiclude. Following intensive groundwater exploitation from the overlying Kurkar Group aquifer, brackish and saline waters were locally encountered in the lower parts of this aquifer and always at the contact with the underlying Yafo Formation aquiclude. The present study revealed that this aquiclude is not a uniform and impervious rock unit, but rather an alternation of pervious and impervious strata within the Yafo Formation containing highly pressured fluids of different - mostly high - salinities. The permeable beds are at an angular unconformity and in direct contact with the overlying Kurkar Group aquifer. The Yafo Formation and the underlying and overlying rock units are dislocated by numerous fault systems, which facilitate accessibility of brines into the Kurkar Group aquifer. The mobilization of the saline fluids and their injection into the Kurkar Group aquifer could be due either to diffusion of saline fluids occurring in the permeable horizons of the Petah Tiqva Member through the clays of the Yafo Formation or to their upconing following intensive pumping in the Coastal Plain aquifer. It could have also been caused by up-dip movement of saline water as the result of overpressure generated by major accumulation of gas in the permeable horizons. Another possible mechanism could be hydraulic contact with pressurized brines up-flowing along fault zones from deep-seated Jurassic or Cretaceous reservoirs. The squeezing of saline interstitial water from the clays of the Yafo Formation into the overlying Kurkar Group aquifer, is of secondary importance for groundwater salinization (its input is comparable with salt input from rain). Depuis longtemps, les «couches de Saqiye», nommées maintenant formation de Yafo, constituant le mur de l'aquifère côtier (série de Kurkar) d'Israël, ont été considérées comme un ensemble extrêmement épais, sans déformation tectonique et totalement imperméable. À la suite de l'exploitation intensive de l'eau souterraine de l'aquifère sus-jacent de la série de Kurkar, des eaux salées et des saumures sont rencontrées occasionnellement dans les parties les plus profondes de cet aquifère et toujours au contact de l'imperméable sous-jacent de la formation de Yafo. Cette étude a révélé que cet imperméable n'est pas une unité géologique uniforme et imperméable, mais qu'il s'agit plutôt d'une alternance de couches perméables et imperméables dans la formation de Yafo contenant des fluides sous des pressions fortes avec des salinités différentes (?) et en général élevées (?). Les niveaux perméables sont en discordance angulaire et en contact direct avec l'aquifère sus-jacent de la série de Kurkar. La formation de Yafo et les unités géologiques situées dessous et dessus sont disloquées par de nombreuses systèmes de failles, qui facilitent le passage des saumures dans l'aquifère de la série de Kurkar. La mobilisation des fluides salins et leur injection dans l'aquifère de Kurkar pourraient être dues soit à la diffusion des fluides salins dans les horizons perméables du Petah Tiqva au travers des argiles de la formation de Yafo, soit leur remontée par upconing sous l'effet de pompages intensifs dans l'aquifère de la plaine côtière. Il peut aussi être causé par la remontée des eaux salines selon le pendage sous l'effet d'une surpression provoquée par une accumulation considérable de gaz dans les horizons imperméables. Un autre mécanisme possible pourrait être un contact hydraulique avec des saumures sous pression, remontant le long des zones de faille depuis des réservoirs profonds jurassiques ou crétacés. L'expulsion d'eau saline interstitielle des argiles de la formation de Yafo dans l'aquifère de Kurkar est d'importance secondaire pour la salinisation de l'eau souterraine cet apport est comparable à celui de sels par les pluies. Durante décadas, las ``Saqiyebeds'' (rebautizadas como Formación Yafo) que se sitúan bajo el acuífero Costero (Grupo Kurkar) de Israel fueron consideradas como un acuicludo extremadamente potente, tectónicamente inalterado y totalmente impermeable. Como resultado de la explotación intensiva del Grupo Kurkar, se produjo la mezcla de aguas salobres y salinas en la zona inferior de dicho acuífero y siempre en el contacto con el acuicludo subyaciente de la Formación Yafo. Este estudio reveló que el acuicludo no es una unidad rocosa uniforme e impermeable, sino que consiste en una alternancia de estratos permeables e impermeables dentro de la Formación Yafo, que contiene fluidos a alta presión de salinidades diferentes pero generalmente elevadas. Las capas permeables se hallan en inconformidad angular y en contacto directo con el acuífero superior del Grupo Kurkar. La Formación Yafo y las unidades rocosas infra- y suprayacentes están dislocadas por numerosos sistemas de fallas, lo que facilita el acceso de las salmueras al acuífero del Grupo Kurkar. Los fluidos de los horizontes permeables del Miembro Petah Tiqva a través de las arcillas de la Formación Yafo o hacia el ascenso de los domos salinos en respuesta a la extracción intensiva en el acuífero del Llano Costero. Podría también haber sido causado por el movimiento a favor del buzamiento de las aguas salinas como resultado de la sobrepresión generada por una acumulación mayor de gas en los horizontes permeables. Otro posible mecanismo podría basarse en el contacto hidráulico con salmueras presurizadas, que fluyen hacia arriba a favor de zonas de falla desde los reservorios profundos del Jurásico o del Cretácico. La extracción de agua salina intersticial desde las arcillas de la Formación Yafo hacia el acuífero superior del Grupo Kurkar es de importancia secundaria para la salinización de las aguas subterráneas, ya que su aportación es comparable a la procedente del agua de lluvia.

Serial hemodynamic monitoring to guide treatment of maternal hypertension leads to reduction in severe hypertension.

PubMed

Stott, D; Papastefanou, I; Paraschiv, D; Clark, K; Kametas, N A

2017-01-01

To examine whether treatment for hypertension in pregnancy that is guided by serial monitoring of maternal central hemodynamics leads to a reduction in the rate of severe hypertension, defined as blood pressure ≥ 160/110 mmHg; and to assess the distinct longitudinal hemodynamic profiles associated with beta-blocker monotherapy, vasodilator monotherapy and dual agent therapy, and their relationships with outcomes, including fetal growth restriction. This was a prospective observational study at a dedicated antenatal hypertension clinic in a tertiary UK hospital. Fifty-two untreated women presenting with hypertension were recruited consecutively and started on treatment, either with a beta-blocker or a vasodilator. The choice of initial antihypertensive agent was determined according to a model constructed previously to predict the response to the beta-blocker labetalol in pregnant women needing antihypertensive treatment. At presentation, the demographic and maternal hemodynamic variables associated with a therapeutic response to labetalol, defined as blood pressure control < 140/90 mmHg with labetalol monotherapy throughout pregnancy, were ascertained and analyzed with logistic regression to create a model to predict sustained blood pressure control as described above. The women were reviewed regularly until delivery and underwent serial hemodynamic monitoring throughout pregnancy. If their blood pressure was elevated, the prediction model was referred to again to determine if alternative antihypertensive therapy, either with additional beta-blocker or a vasodilator, should be added. Treatment by referring to results of serial hemodynamic monitoring reduced the rate of severe antenatal hypertension from 18% to 3.8%. Seventy-seven percent of women were initially prescribed a beta-blocker and 23% a vasodilator. The group that maintained good blood pressure control with beta-blocker monotherapy had the best fetal and maternal outcomes. They had lower blood pressures at presentation and throughout gestation, demonstrated well-maintained cardiac output and had the lowest rates of fetal growth restriction. The groups that required dual therapy to control their blood pressure had persistently higher blood pressure and rate of fetal growth restriction. The groups that required vasodilator therapy due to high levels of peripheral vascular resistance, either at presentation or later in pregnancy, accounted for 81% of cases with fetal growth restriction. Using serial hemodynamic monitoring in pregnancy to guide treatment of hypertension significantly reduces the rate of severe hypertension and allows identification of high-resistance, low-output hypertensive pregnancies that are associated with an increased rate of fetal growth restriction. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Examinar si el tratamiento para la hipertensión en el embarazo guiado por un seguimiento en serie de las principales constantes hemodinámicas de la madre conduce a una reducción en la tasa de hipertensión grave, definida como presión arterial ≥ 160/110 mmHg; y evaluar los diferentes perfiles hemodinámicos longitudinales asociados a la monoterapia con beta-bloqueantes, la monoterapia con vasodilatadores y la terapia dual, y su relación con los resultados, como la restricción del crecimiento fetal. MÉTODOS: Se realizó un estudio observacional prospectivo en una clínica especializada en hipertensión prenatal de un hospital de atención terciaria del Reino Unido. Se reclutaron consecutivamente a cincuenta y dos mujeres no tratadas que presentaban hipertensión y se comenzó a tratarlas, bien con un beta-bloqueante o bien con un vasodilatador. La elección del agente antihipertensivo inicial se determinó de acuerdo con un modelo elaborado previamente para predecir la respuesta al beta-bloqueante labetalol en mujeres embarazadas que necesitaban tratamiento antihipertensivo. Al inicio se registraron las características demográficas y las variables hemodinámicas maternas asociadas con una respuesta terapéutica al labetalol, definida como un control de la presión arterial < 140/90 mmHg con monoterapia de labetalol durante todo el embarazo que se analizó mediante regresión logística para crear un modelo con el que pronosticar un control sostenido de la presión arterial, como se describe arriba. Las mujeres fueron sometidas a revisiones regulares hasta el momento del parto y se les hizo un seguimiento hemodinámico en serie durante todo el embarazo. Si la presión arterial era elevada, se empleó de nuevo el modelo de predicción para determinar si se debería añadir un tratamiento antihipertensivo alternativo, ya sea con un beta-bloqueante adicional o con un vasodilatador. El tratamiento que tuvo en cuenta los resultados del seguimiento hemodinámico en serie redujo la tasa de hipertensión prenatal grave del 18% al 3,8%. Al 77% de las mujeres se les recetó inicialmente un y al 23% un vasodilatador. El grupo que mantuvo un buen control de la presión arterial con monoterapia de beta-bloqueantes logró mejores resultados fetales y maternos. Este grupo tuvo menor presión arterial al inicio y durante toda la gestación, mostró un gasto cardíaco en buen estado y tuvo las tasas más bajas de restricción del crecimiento fetal. Los grupos que requirieron terapia dual para controlar su presión arterial mostraron persistentemente una mayor presión arterial y un mayor ritmo de restricción del crecimiento fetal. Los grupos que requirieron tratamiento vasodilatador debido a los altos niveles de resistencia vascular periférica, tanto al inicio como durante el embarazo, representaron el 81% de los casos con restricción del crecimiento fetal. CONCLUSIÓN: El uso de un seguimiento hemodinámico en serie en el embarazo como guía para el tratamiento de la hipertensión reduce significativamente la tasa de hipertensión severa y permite la identificación de embarazos con hipertensión de alta resistencia y malos resultados, asociados con una mayor tasa de restricción del crecimiento fetal. : (≥ 160/110 mmHg);β、,()。 : 。52、,β。β。,(<140/90 mmHg),logistic,。,。,(β)。 : ,18%3.8%。77%β,23%。β。,,。,。,81%。 : ,,、。. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Geochemical and stable isotopic evolution of the Guarani Aquifer System in the state of São Paulo, Brazil

NASA Astrophysics Data System (ADS)

Sracek, Ondra; Hirata, Ricardo

2002-09-01

The purpose of this report is to explain geochemical and stable isotopes trends in the Brazilian unit of the Guarani Aquifer System (Botucatu and Piramboia aquifers) in São Paulo State, Brazil. Trends of dissolved species concentrations and geochemical modeling indicated a significant role of cation exchange and dissolution of carbonates in downgradient evolution of groundwater chemistry. Loss of calcium by the exchange for sodium drives dissolution of carbonates and results in Na-HCO3 type of groundwater. The cation-exchange front moves downgradient at probably much slower rate compared to the velocity of groundwater flow and at present is located near to the cities of Sertãozinho and Águas de Santa Barbara (wells PZ-34 and PZ-148, respectively) in a shallow confined area, 50-70 km from the recharge zone. Part of the sodium probably enters the Guarani Aquifer System. together with chloride and sulfate from the underlying Piramboia Formation by diffusion related to the dissolution of evaporates like halite and gypsum. High concentrations of fluorine (up to 13.3 mg/L) can be explained by dissolution of mineral fluoride also driven by cation exchange. However, it is unclear if the dissolution takes place directly in the Guarani Aquifer System or in the overlying basaltic Serra Geral Formation. There is depletion in δ2H and δ18O values in groundwater downgradient. Values of δ13C(DIC) are enriched downgradient, indicating dissolution of calcite under closed system conditions. Values of δ13C(DIC) in deep geothermal wells are very high (>-6.0‰) and probably indicate isotopic exchange with carbonates with δ13C about -3.0‰. Future work should be based on evaluation of vertical fluxes and potential for penetration of contamination to the Guarani Aquifer System. Résumé. Cet article a pour objet d'expliquer l'évolution de la géochimie et des isotopes stables dans l'unité brésilienne du système aquifère du Guarani (aquifères de Botucatu et Piramboia), dans l'État de Sao Paulo (Brésil). L'évolution des concentrations des espèces dissoutes et la modélisation géochimique ont fait apparaître le rôle notable des échanges de cations et de la dissolution des carbonates de l'amont vers l'aval des nappes. La perte de calcium par échange de cation avec le sodium pilote la dissolution des carbonates et donne naissance à des eaux souterraines à faciès Na-HCO3. Le front d'échange de cation se déplace vers l'aval probablement plus lentement que la vitesse d'écoulement de l'eau souterraine et est actuellement situé à proximité des villes de Sertaozinho et de Aguas de Santa Barbara (respectivement puits PZ-34 et PZ-148), dans une zone captive proche de la surface, à 50-70 km de la zone de recharge. Une partie du sodium provient probablement du système aquifère du Guarani, associée aux chlorures et aux sulfates de la formation Piramboia sous-jacente, par diffusion liée à la dissolution d'évaporites comme la halite et le gypse. De fortes concentrations en fluorures (jusqu'à 13,3 mg/L) peuvent être expliquées par la dissolution d'un minéral fluoré également pilotée par l'échange de cations. Cependant, on ne sait pas bien si la dissolution intervient directement dans le système aquifère du Guarani ou dans la formation basaltique sus-jacente de Serra Geral. Les valeurs de δ2H et δ18O décroissent vers l'aval de la nappe. Les valeurs de δ13C du carbone minéral dissous sont enrichies vers l'aval, indiquant qu'il se produit une dissolution de calcite en système fermé. Les valeurs de δ13C du carbone minéral dissous dans les puits géothermaux profonds sont très élevées (supérieures à -6,0‰) et rendent probablement compte d'échanges isotopiques avec des carbonates possédant un δ13C d'environ -3,0‰. De prochaines études devront s'attacher à évaluer les flux verticaux et le potentiel de pénétration de contamination du système aquifère du Guarani. Resumen. El propósito de este informe es explicar las tendencias geoquímicas y de los isótopos estables en la unidad brasileña del Sistema Acuífero Guaraní (acuíferos de Botucatu y Piramboya), en el Estado de Sao Paulo. Las concentraciones de especies disueltas y los resultados de modelaciones geoquímicas indican que el intercambio catiónico y la disolución de carbonatos desempeñan un papel importante en la evolución aguas abajo del acuífero. La disminución de calcio por el intercambio con sodio origina la disolución de carbonatos, dando lugar a aguas subterráneas de tipo bicarbonatado sódico. El frente de intercambio catiónico se desplaza a una velocidad probablemente mucho más lenta que la del flujo de agua; actualmente, se halla cerca de las ciudades de Sertaozinho y Aguas de Santa Bárbara (pozos PZ-34 y PZ-148, respectivamente), en una zona confinada somera que dista entre 50 y 70 km del área de recarga. Parte del sodio entra probablemente en el Sistema Acuífero Guaraní junto con el cloruro y el sulfato procedentes de la Formación Piramboia inferior, debido a la difusión relacionada con la disolución de evaporitas como la halita y los yesos. Se puede explicar las elevadas concentraciones de flúor (hasta 13,3 mg/L) por la disolución de fluoruro mineral, que sucede también por intercambio catiónico. Sin embargo, no está claro si la disolución ocurre directamente en el Sistema Acuífero Guaraní o en la Formación basáltica superior de Serra Geral. Hay una reducción de δ2H y de δ18O a favor del gradiente hidráulico. Hay un enriquecimiento en δ13C inorgánico aguas abajo, lo que indica que la calcita se disuelve en condiciones de sistema cerrado. Los valores de δ13C inorgánico en pozos geotérmicos profundos son muy altos (mayores que -6,0‰), y probablemente apuntan a un intercambio isotópico con carbonatos de δ13C que tiene un valor del orden del -3,0‰. Las líneas de investigación deberían centrarse en evaluar los flujos verticales y el potencial de penetración de contaminantes en el Sistema Acuífero Guaraní.

Wirkungen biogener Amine auf die Erregungs-Sekretions-Kopplung in der Speicheldrüse von Periplaneta americana (L.)

NASA Astrophysics Data System (ADS)

Rietdorf, Katja

2003-07-01

In der vorliegenden Arbeit habe ich wichtige Teilmechanismen der Erregungs-Sekretionskopplung in der Speicheldrüse der Schabe Periplaneta americana (L.) untersucht. Die Speicheldrüse ist von dopaminergen und serotonergen Fasern innerviert (Baumann et al., 2002). Beide Transmitter stimulieren eine unterschiedliche Reaktion der Drüse: Dopamin (DA) stimuliert die P-Zellen der Acini und die Ausführgangzellen, während Serotonin (5-HT) die P- und C-Zellen der Acini stimuliert, nicht jedoch die Ausführgangzellen. Der Endspeichel ist nach einer DA-Stimulierung proteinfrei. Dagegen enthält er nach einer 5-HT-Stimulierung Proteine, die von den C-Zellen sezerniert werden (Just & Walz, 1996). Im ersten Teil meiner Arbeit habe ich mittels Kapillarelektrophoretischer Analyse (CE-Analyse) die Elektrolytkonzentrationen im Endspeichel untersucht sowie die Raten der Flüssigkeitssekretion gemessen. Damit wollte ich klären, welche Transporter an der Sekretion des Primärspeichels und an dessen Modifikation beteiligt sind. Ausserdem wollte ich die Rolle der transportaktiven Epithelzellen der Ausführgänge für die Modifikation des Primärspeichels untersuchen. Dafür habe ich einen Vergleich der Elektrolytkonzentrationen im DA- und 5-HT-stimulierten Endspeichel durchgeführt. Der Elektrolytgehalt des DA- und 5-HT-stimulierten Endspeichels unterscheidet sich nicht signifikant voneinander. Er ist nach beiden Stimulierungen hypoosmotisch zum verwendeten Ringer. Die Ausführgangzellen werden durch DA stimuliert und modifizieren den Primärspeichel durch eine netto-Ionenreabsorption. Meine Versuche zeigen jedoch, dass auch die während einer 5-HT-Stimulierung der Drüse unstimulierten Ausführgangzellen den Primärspeichel modifizieren. In einer nachfolgenden Versuchsreihe habe ich den Einfluss von Ouabain, einem Hemmstoff der Na+-K+-ATPase, und Bumetanid, einem Hemmstoff des NKCC, auf die Raten der Flüssigkeitssekretion sowie den Elektrolytgehalt des Endspeichels untersucht. Ich habe gefunden, dass die Aktivität der Na+-K+-ATPase wichtig für die Modifikation des DA-stimulierten Primärspeichels ist. Im Gegensatz dazu ist sie für die Modifikation des 5-HT-stimulierten Primärspeichels nicht von Bedeutung. Bezüglich der Flüssigkeitssekretion habe ich keinen Einfluss der Na+-K+-ATPase-Aktivität auf die DA-stimulierten Sekretionsraten gefunden, dagegen ist die 5-HT-stimulierte Sekretionsrate in Anwesenheit von Ouabain gesteigert. Die Aktivität des NKCC ist für beide sekretorische Prozesse, die Ionen- und die Flüssigkeitssekretion, wichtig. Eine Hemmung des NKCC bewirkt eine signifikante Verringerung der Raten der Flüssigkeitssekretion nach DA- und 5-HT-Stimulierung sowie in beiden Fällen einen signifikanten Abfall der Ionenkonzentrationen im Endspeichel. Im zweiten Teil meiner Arbeit habe ich versucht, Änderungen der intrazellulären Ionenkonzentrationen in den Acinuszellen während einer DA- oder 5-HT-Stimulierung zu messen. Diese Experimente sollten mit der Methode des "ratiometric imaging" durchgeführt werden. Messungen mit dem Ca2+-sensitiven Fluoreszenzfarbstoff Fura-2 zeigten keinen globalen Anstieg in der intrazellulären Ca2+-Konzentration der P-Zellen. Aufgrund von Problemen mit einer schlechten Beladung der Zellen, einer starken und sich während der Stimulierung ändernden Autofluoreszenz der Zellen sowie Änderungen im Zellvolumen wurden keine Messungen mit Na+- und K+-sensitiven Fluoreszenzfarbstoffen durchgeführt. Im dritten Teil dieser Arbeit habe ich die intrazellulären Signalwege untersucht, die zwischen einer 5-HT-Stimulierung der Drüse und der Proteinsekretion vermitteln. Dazu wurde der Proteingehalt im Endspeichel biochemisch mittels eines modifizierten Bradford Assay gemessen. Eine erstellte Dosis-Wirkungskurve zeigt, dass die Rate der Proteinsekretion von der zur Stimulierung verwendeten 5-HT-Konzentration abhängt. In einer Serie von Experimenten habe ich die intrazellulären Konzentrationen von Ca2+, cAMP und / oder cGMP erhöht und anschließend den Proteingehalt im Endspeichel gemessen. Ein Anstieg der intrazellulären Ca2+-Konzentration aktiviert nur eine geringe Rate der Proteinsekretion. Dagegen kann die Steigerung der intrazellulären cAMP-Konzentration eine stärkere Proteinsekretion aktivieren, die sich nicht signifikant von der nach 5-HT-Stimulierung unterscheidet. Die cAMP-stimulierte Proteinsekretion kann durch gleichzeitige Erhöhung der intrazellulären Ca2+-Konzentration weiter gesteigert werden. Dagegen aktivierte eine Erhöhung der intrazellulären cGMP-Konzentration die Proteinsekretion nicht. Aufgrund dieser Ergebnisse postuliere ich die Existenz eines die Adenylatcyclase aktivierenden 5-HT-Rezeptors in der Basolateralmembran der C-Zellen. The aim of this PhD-work was to investigate major mechanisms of excitation-secretion coupling in the salivary gland of the cockroach Periplaneta americana (L.). This salivary gland is innervated by dopaminergic and serotonergic fibres (Baumann et al., 2002). The two transmitters stimulate different processes in the gland: Dopamine (DA) stimulates the p-cells of the acini and the salivary duct cells, whereas 5-HT (serotonin) activates the p- and the c-cells of the acini, but not the salivary duct cells. Final saliva is completely protein-free after dopamine stimulation. It contains proteins, which are secreted by the c-cells of the acini, after a 5-HT-stimulation (Just & Walz, 1996). In the first part of my work I measured the electrolytic composition of the final saliva by capillary electrophoretic analysis and measured the rates of fluid secretion, in order to answer the following questions: 1.) Which transporters affect the production of primary saliva and its modification? 2.) What is the function of the transport-active salivary duct cells for the modification of the primary saliva? Electrolytic composition of the DA- and 5-HT-stimulated final saliva is not significantly different from each other, and is hypoosmotic to the Ringer used. Salivary duct cells are stimulated by DA and modify the primary saliva by a netto ion-reabsorption. My experiments also show that the duct cells, which are unstimulated during a 5-HT-stimulation of the gland, modify the primary saliva. In the next series of experiments I investigated the effects of ouabain, an inhibitor of the Na+-K+-ATPase, and bumetanide, an inhibitor of the NKCC on the rates of fluid secretion and the electrolytic composition of the final saliva. I found, that the activity of the Na+-K+-ATPase is important for the modification of DA-stimulated primary saliva during its flow through the stimulated duct system. In contrast, it is not important for modification of the 5-HT-stimulated primary saliva. Inhibition of the Na+-K+-ATPase does not affect rates of DA-stimulated fluid secretion, but it increases the rates of 5-HT-stimulated fluid secretion. Activity of the NKCC is important for both secretory processes: the ion and the fluid secretion. Inhibition of the NKCC results in a significant drop in the rates of fluid secretion after DA- and 5-HT-stimulation, as well as a drop in electrolytic concentrations in the saliva. In the second part of my work, I tried to measure changes in the intracellular ionic concentrations (Ca2+, Na+, and K+) within the acinar cells during a DA- or 5-HT-stimulation. The experiments should be performed by ratiometric imaging. Measurements with the Ca2+-sensitive dye Fura-2 did not show any global increase in the intracellular Ca2+-concentration in the p-cells of the acini. Problems concerning a bad loading of the cells, a strong autofluorescence which changed during the time course of the stimulation, as well as changes in the cell volume were the reason, that no measurements using Na+- or K+-sensitive dyes were performed. In the third part of my work I investigated the intracellular signalling pathways, which activate protein secretion after 5-HT-stimulation of the gland. A modified Bradford Assay was used for measuring the protein content in the final saliva. In a dose-response curve I showed that rates of protein secretion are dependent on the 5-HT-concentrations used to stimulate the glands. In another set of experiments I increased the intracellular concentrations of Ca2+, cAMP and / or cGMP, and measured the protein content in the final saliva. An increase in the intracellular Ca2+-concentration activates only a low rate of protein secretion. After an increase in the intracellular cAMP-concentration a much higher rate of protein secretion can be activated, which is not significantly different from the 5-HT stimulated rate of protein secretion. The cAMP-stimulated protein secretion can be further increased by a simultaneous rise in the intracellular Ca2+-concentration. In contrast, cGMP does not activate protein secretion. Therefore I propose the expression of an adenylyl cyclase activating 5-HT-receptor in the basolateral membrane of the protein secreting c-cells.

Farmyard Manure and Fertilizer Effects on Seed Potato (Solanum tuberosum L.) Yield in Green House Production

NASA Astrophysics Data System (ADS)

László, M.

2009-04-01

Nowadays is widely well know that the potato is an important vegetable crop at Brazíl. It is grown on about 173.000 ha, with total yield of 2.6 million tons year-1. The average yield is 15 t ha-1. This level is very low because degeneration of crop is rapid under high temperature and high viruses pressure. Therefore seed potato propagation and production is principal on consumption potato production. This is why we found it necessary to develop it. The latossolo vermelho soil-farmyard manure- burnt rice straw-fertilizer 4N:14P:8K greenhouse pot trial was set up at the National Vegetable Crops Research Center, Brasília-DF, Brazíl in 1990. The methods of the experiments were soil x farmyard manure x burnt rice straw, soil x 4N:14P:8K fertilizer and soil x farmyard manure x burnt rice straw x 4N:14P:8K fertilizer on randomized block design in total 29 combination of treatments in 5, 5 and 3 repetitions with in a total parcel of 116. According to chemical analysis of the a., soil, b., farmyard manure and c., burnt rice straw the agrochemistry parameters were as follows (estimated datas): a., latossolo vermelho soil: CaCO3 0.3-0.7%, humo 0.9-1.0%, pH (H2O) 5.3, pH (KCl) 4.5, AL- P2O5 3.2-3.5 mg kg-1, AL- K2O 180 mg kg-1, Mg (KCl) 70 mg kg-1, EDTA-Zn 0.5-0.8 mg kg-1, EDTA-Cu 0.5-0.6 mg kg-1, b., farmyard manure: N 1.8 g kg-1, P2O5 2.0 g kg-1, K2O 4.0 g kg-1, c., burnt rice straw: N 0.8 g kg-1, P2O5 7.0 g kg-1, K2O 4.5 g kg-1. The experimental datas were estimated by analysis of variance, ANOVA and MANOVA. The main conclusions were as follows: 1. Mixture of 80% latossolo vermelho, 10% burnt rice straw and 10% farmyard manure were shown best performance on seed potato productivity. The piece of tubers with a 0-20 mm (consumption seeds) was increased by 77%. 2. Total seed potato number was reached maximum at 10.8 g pot-1 4N:14P:8K fertilizer regarding to average of treatments with a 33%. 3. Dry biomassa production plant-1 was decreased by high dose of 4N:14P:8K fertilizer (18.0 g pot-1) with a hard effect (57%). Our results are shown that it was possible developing of the seed potato production under tropical greenhouse conditions by optimalised soil-organic matter-fertilizer system. This datas should be as indicators to sustainable field potato advisory systems. Keywords: potato (Solanum tuberosum L.), greenhouse, latossolo vermelho soil, farmyard manure, burnt rice straw, 4N:14P:8K fertilizer, sustainability, yield Introducáo: Importância e situação actual em produção da batata no Brazíl A batata é atualmente uma das hortaliças de maior importância no Brasíl (Márton 2000a., 2000b.) com um cultivo annual médio de 173.000 ha e uma produção de 2600000 t. A produtividade médio nacional é de 15 t ha-1, muito baixa se considerar que é possivel a obtenção de rendimentos acima de 40 t ha-1. Observa- se também, que existe variação no produtividade entre regiões e estados. E importante como fonte de alimento pelo seu alto valor nutricional a quantidade produzida muito superior por unidade de área a tempo, se comparada com diversas outras culturas (László 2000b., 2000c.). Os estados que tradicionalmente produzem batata em maior ou menor escala são indicados em seguente: Pernambuco, Ceará, Sergipe, Goiás, Mato Grosso, Mato Grosso do Sul, Rondonia e Acre. Os plantios predominantes são o das águas e das secas, sendo o de inverno bem menos expressivo, pois poucas áreas permitem o seu cultivo, na maioria dos casos necessitando- se de irrigação. Considerando as três épocas de plantio e diferentes condições climaticas brasileiras, podemos definir de um modo geral o plantio de batata no Brasíl da seguinte maneira: Nordeste e Centro- Oeste- plantio de inverno, Sudeste- plantio das águas, secas e inverno, Sul- plantio das aguas, secas e inverno. Sendo este último em áreas muito limitadas. Dentre as hortaliças a batata é uma das culturas mais estudadas actualmente. Os principais problemas que afetam a cultura da batata podem ser de ordem agronómica, economica e comercial. Como exemplos destes podem ser citados: o uso racional de matérias orgânicos, esterco de curral e inorgânico fertilizantes. Efeito de materias orgnicânicos e N, P, K elementos minerais para produção da batata As necessidades em N, P, e K elementos minerais da batata são superidas pela aplicação apropriada de matérias orgânicos, esterco de currals, fertilizantes ao solo, combinada com a ambiente (Márton 2001a., 2001b.), época adequada e posição ideal de aplicá- lo. Efeito da materias orgânicos O suprimento de N á batateira provém principalmente da matéria orgânica do solo e do fertilizante aplicado (László 2000a., Márton et all. 2000.). Embora não seja muito praticado no Brasíl, a incorporação de esterco ao solo é fator de aumento da produção de tuberculos. Este resultado favorável poderia ser atribuído ao melhoramento da estrutura do solo, á maior retenção de água pelo e mesmo favorecendo o melhor desenvolvimento do sistema radicular da planta. A batata pode ser cultivada em todo tipo de solo desde que tenha boa drenagem e seja bem estruturado. Isto é tem que ser bem aerado e permitir o bom desenvolvimento dos órgãos subterráneos da batateira. Sem de matéria orgânicos e esterco de curral a tendencia de determinados solos formar crosta, oferecendo uma alta resisténcia mecánica á emergéncia das plantas, pode ser um determinante de stands desuniformes. A cause primaria da formação de crostas é a destruição dos agregados do solo pela excessiva manipulação mecánica resultando em aeração reduzida e aumento da densidade e coesão das particulas do solo. O encrostamento do solo pode ser reduzido através com matérias orgânicos. De maneira geral, a produção de tuberculos em solo de baixa potencialidade (aqueles em que a penetração das raizes é dificultada pela compactação, textura argilosa ou com camadas no solo) será menor do que nagueles com alta potencialidade (boa textura e adequada retenção de agua). Efeito do nitrogênio No Brazíl em todas regiões onde se cultiva batata é raro encontrar solos com elevado teor de nitrogênio e que não precisam de quantidades desta elemento. É o elemento que governa o padrão de desenvolvimento da planta, estimulando principalmente o crescimento da parte aérea (Kádár et all. 2000., László 2000.). Para se obter rendimento de tubérculos é necessário um rápido e curto periodo de desenvolvimento da parte aérea e uma fase de acúmulo maior possível. Para tanto, devem ser evitadas doses muito altas de nitrogênio e, principalmente, se aplicadas tardiamente, pois haverá demasiado desenvolvimento de folhas que demorarão mais a finalizar seu crescimento e maturação. Isto implicará na redução do periodo de intenso desenvolvimento dos tubérculos e armazenagem do amido, resultando em menor produção. Há risco para a saúde na ingestão de alimentos com altos teores de nitrato e nitrito, havendo preocupação com o efeito de doses mais altas de nitrogênio sobre os teores dos mesmos nos tuberculos. Embora haja diferenças entre cultivares, localidades e períodos de armazenamento, há estudos mostrando que a fertilização com até 150 kg ha-1 de nitrogênio não foi suficiente para propiciar niveis preocupantes de nitrato nos tuberculos colhidos. Efeito do fósforo A grande maioria dos solos brasileiros cultivados com batata apresentam limitações ao bom desenvolvimento e produção da cultura em função dos baixos níveis de fósforo. Isto significa que aumentos de produção quase sempre ocorrem quando o solo recebe adubação fosfatada (László 2001a.). Estes aumentos são mais marcantes em solos nunca antes adubados ou com baixo teor de fósforo. Nestes, dificilmente alcanca- se a produção máxima com níveis reduzidos de fósforo. Não seria exagerado supor níveis de 600 a 800 kg ha-1 de P2O5, como sendo aqueles que iriam proporcionar produção máximas, principalmente em solos mais ácidos e pobres em matéria orgânico. A adubação fosfatada é muito importante no crescimento inicial da planta e, além de aumentar a produção de tuberculos em peso e números, aumenta também a quantidade e qualidade do amido neles contidos e reduz perdas durante o armazenamento dos mesmos. A quantidade de fósforo a aplicar dependerá da análise do solo considerando- se principalmente o nível de P existente e a textura do solo. Solos de textura média e arenosa necessitam maior conteúdo de fósforo do que os de textura argilosa para serem considerandos solos de baixo, médio ou alto teor de fósfato. Efeito da potássica Embora seja o elemento mais absorbido pela batateira, nem sempre há resposta positiva da aduba potássica sobre o rendimento da cultura. Provavelmente isto esteja relacionado com níveis elevados deste elemento no solo (Kurnik et all. 2001.). Entretanto, em solos com médios e baixos teores de potássio, aumentos significativos são conseguidos. Por isto, as recomendações de adubação com potássio, nas diversas regiões do mundo, variam de 50-300 kg ha-1 de K2O. Resultados de trabalhos em brasiléiros têm demonstrado que a aduba potássica pode ser substituída pela aplicação de 150 m3 ha-1 de vinhaça de cana de açúcar. Ao elevar- se a dose de fertilização potássica deverá haver precaução para que a adubação magnesiana seja suficiente. O K além de aumentar a produção, em solos deficientes, aumenta também o tamanho dos tubérculos produzidos, e a proporção de tubérculos grandes. Deficiência no suprimento de potássio á planta pode acarretar produção de tubérculos com elevada susceptibilidade aos danos mecánicos pós-colheita. Os tubérculos injuriados enegrecem facilmente e este enegrecimento é inversamente proporcional á quantidade de potássio nos tuberculos. Ademais, quando fritos dão origem a um produto escuro, de baixa valor comercial. Manejo de adubação Diversos fatores como potencial de produção do solo, modo de aplicação do fertilizante dentre outro fatores afetam a resposta da batateira á aplicação de fertilizantes (Refschneider 1987.). Depreende- se pois que no estabelecimento de um nivel ideal de fertilização as variáveis planta, solo e condições climaticas devem ser visualizadas como um sistema pouco provável de ser homogeneo mesmo em nivel de fazenda. Como tal, generalizações a respeito de doses ou niveis de fertlização são difíceis de serem feitas, recomendações exigem julgamento hábil por parte do fazendeiro ou do tecnico responsavel pela cultura (Márton 2001a., 2001b.). Este julgamento será mais preciso conhecendo- se pontos que serão rápidamente discutidos a seguir. A taxa de absorção de nutrientes é governada pela concentração externa ou suprimento de nutrientes pelo solo e a demanda do nutriente criada pelo desenvolvimento e funcinamento normal dos diversos órgãos das plantas. O nivel de nutrientes na solução do solo deve ser suficiamente alto para que suas taxas de absorção não sejam limitantes ao crescimento. Por outro lado, não deve ser demasiado para causar excessiva absorção de outros nutrientes. Forte associação existe entre a absorção de nutrientes e o desenvolvimento da planta. De maneira geral, a fase de rapido desenvolvimento da cultura é acompanhada por um grande aumento na absorção de nutrientes com a taxa de absorção declinado quando a taxa de crescimento diminuiu. Normalmente todos os fertilizantes potássicos e fosfatados são adicionados ao solo na época do plantio. O nitrogênio normalmente é parcelado. Cerca de 2 por 3 do nível recomendado é colocado no sulco de plantio e o restante adicionado por ocasião da amontoa. É uma prática tradicinal e com pouco suporte experimental no condiõces brasileiras. Espera -se que a aplicação parcelada do nitrogênio e mesmo do potássio possem ser benéficas quando houver chuva excessiva ou irrigações mal executadas principalmente em solos mais arenosos onde poderá ocorrer a lixiviacão dos mesmos (Márton 2001a., 2001b.). O parcelamento poderá também ser benéfico quando elevados níveis de fertilizantes porém recomendandos e a aplicação por feita nos sulcos de plantio, pois evitar-se ia assim, elevada concentração salina em torno dos tubérculos plantados, embora a aplicação á lanco, em toda área, possa ser opção vantajosa. Quantidades corretas de fertilizantes, posição ideal e época certa de aplicação, combinadas adequadamente, definem o programa de adubação da batata. Esse programa é variável de acordo com o solo, a batata e condisões ambientais (Márton 2001a.). A dose de um elemento a ser aplicada em batata, é função da quantidade desse elemento suprida pelo solo e da percentagem de recuperação do elemento adicionado ao solo como fertilizante. Resultados experimentais comparando a aplicação de fertilizante á lanco ou localizado mostram respostas variadas sobre a produção. E possivel encontrar resultados iguais em ambos os métodos, de supremacia da aplicação á lanco ou da aplicação localizada (Kurnik et all. 2001.). Parece que baixas quantidades de fertilizantes são mais eficiemente utilizadas quando aplicação nos sulcos de plantios. Entretanto o potancial de produção pode ser aumentando com alta ou mesmo moderada quantidade de fertilizantes aplicados á lanço. A recomendação geral de colocar o adubo no sulco de plantio da batata merece ser questionada. É uma recomendação válida ao entender- se que a batata responde bastante á aplicação de fósforo, que os solos brasileiros tem alta capacidade de absorção de fósforo e que haverá maior proliferação de raízes na área fertilizada. Uma indagação aparece: um solo com baxa disponibilidade de fósforo fora da zona fertilizada permitiria o desenvolvimento ótimo da planta. Algumas evidéncias mostram, para outras espécies, que grande parte do sistema radicular, deve estar exposta ao fósforo para suprir as necessidades das plantas. Ademais, há um determinado valor de concentração de fósforo, na solução do solo, acima da qual a taxa de absorção não é aumentada. Essas considerações suscitam a possibilidade de questionar se a aplicação de fósforo em sulcos seria a forma mais eficiente de usá-lo quando se pretende alcancar elevadas produções. Deve-se lembrar entretanto, que solos tropicais, ainda com baixos teores fósforo e alta capacidade de adsorção, seria necessária dose muito elevada de P, quando aplicada á lanço, em todo o terreno. Se a aplicação localizada do fósforo pode, em parte, ser explicada, a do nitrogênio e potássio não são facilmente justificadas sob o aspecto de eficiéncia de utilização. Pelo contrário, ela pode ser questionada, principalmente pelas suas caracteristicas de difusão, pelo efeito que altas concentração de amónio e cloreto podem ter sobre a pressão osmotica da solução do solo junto aos tubérculos plantados, pelo efeito negativo do cloreto sobre a absorção de fósforo e também sobre a capacidade produtiva das plantas. Portanto, existe a possibilidade de ocorrer toxidez de amónio e de cloreto ao se aplicar doses altas dos fertilizantes nos sulcos de plantios. Isto pode determinar uma menor eficiéncia no uso dos fertilizantes. Materiais e Metodos: Nos desenvolverémos os três experimentos (i.e.: 1., 2., 3.) para aumentár-se do produção e produtividade da batata (Solanum tuberosum L.) semente pré- básica no casa de vegetação com diferentes doságens do latossolo vermelho novo, do esterco de curral e do adubo fórmula 4N:14P:8K no Empresa Brasileira de Pesquisa Agropecuaria- Centro Nacional de Pesquisas de Hortaliças, da Brazília-DF no 1990. Caracteristicas agroquímicas do solo em faixa arado (dados estimados), e conteudos N, P2O5, K2O do esterco de curral e palha de arroz queimado (dados estimados): a., caracteristicas agroquímicas do solo latossolo vermelho (solo novo: nunca foi usado para produção da batata semente): CaCO3 0.3-0.7%, humo 0.9-1.0%, pH (H2O) 5.3, pH (KCl) 4.5, AL- P2O5 3.2-3.5 mg kg-1, AL- K2O 180 mg kg-1, Mg (KCl) 70 mg kg-1, EDTA-Zn 0.5-0.8 mg kg-1, EDTA-Cu 0.5-0.6 mg kg-1 com abastecer fraco destes elementos, b., conteudos N, P2O5, K2O do esterco de curral (qualidade médio): N 1.8 g kg-1, P2O5 2.0 g kg-1, K2O 4.0 g kg-1, c., conteudos N, P2O5, K2O do palha de arroz queimado (palha de arroz foi queimado em um especial forno): N 0.8 g kg-1, P2O5 7.0 g kg-1, K2O 4.5 g kg-1. Nestas provas usarémos para controle a *mistura padrão. O este tratamento é a composição usual neste programa i.e.: 150 l de solo novo, 50 l de palha de arroz queimado, 50 l de esterco de curral, 350 gramas de cal e 300 gramas de adubo da fórmula 4N:14P:8K. Experimento 1. Efeito de diferentes misturas para produção da batata semente pré- básica em casa de vegetação O experimento foi instalado considerando-se sete misturas de substrato (latossolo vermelho novo, esterco de curral, palha de arroz queimado) em 3000 cm3 volume de capacidade de vasos preto com cinco repetições, no delineamento experimental de blocos ao acaso, na mésas experimentais em caso de vegetação. A cultivar foi a Achat, com plãntulas provenientes de cultura de tecidos. A data de plantio foi 18.04.1990. Plantarémos em cada vaso 3-3 "in vitro" plantulas com raiz embaixo de 4cm de superficie da mistura no vasos. Irrigarémos com 12 mm quantidade da augua 2 vezes por semana. Para produção aplicarémos sistema de proteção de plantas como usados no Brasíl. Ambiente foi controlado com ventilação automatizado. Temperatura médio foi 22 0C e humidade médio foi 68% durante de experimento. A data de colheta foi 04.07.1990. As pesagens foram feitos como peso fresco. Os resultados foram submetidos a analise de variáncia, ANOVA. As misturas do substrato utilizadas foram como a seguir no Tabela 1. Experimento 2. Efeito de adubo 4N:14P:8K para produção da batata semente pré- básica em casa de vegetação O experimento foi instalado considerando-se 9 dosagens de adubo da fórmula 4N:14P:8K com latossolo vermelho novo em 3000 cm3 volume de capacidade de vasos preto com cinco repetições, no delineamento experimental de blocos ao acaso na mésas experimentais em casa de vegetação. O adubo foi posicionando no solo de 4 cm abaixo de superficie do solo. A cultivar foi a Achat, com plãntulas provenientes de cultura de tecidos. A data de plantio foi 18.04.1990. Plantarémos em cada vaso 3-3 "in vitro" plantulas com raiz embaixo de 4cm de superficie da mistura no vasos. Irrigarémos com 12 mm quantidade da augua 2 vezes por semana. Para produção aplicarémos sistema de proteção de plantas como usados no Brasíl. Ambiente foi controlado com ventilação automatizado. Temperatura médio foi 22 0C e humidade médio foi 68% durante de experimento. A data de colheta foi 04.07.1990. As pesagens foram feitos como peso fresco. Os resultados foram submetidos a analise de variáncia, ANOVA. As doságens de adubo foram como a seguir no Tabela 2. Experimento 3. Efeito de latossolo vermelho novo, palha de arroz queimado e adubo 4N:14P:8K para produção da batata semente pré- básica em casa de vegetação Para pesquisar estes efeitos o experimento tipo de (2 x 6) foi instalado considerando-se as combinações entre duas misturas (i.e.: 1., 2.) e seis doságens de adubo complexo 4N:14P:8K, com três repetições, no delineamento experimental de bloco ao acaso, sendo 1 vaso (3000 cm3 volume de capacidade de vasos preto) por parcela na mésas experimentais em casa de vegetação. O adubo foi posicionando no solo de 4 cm abaixo de superficie do solo. A cultivar utilizada foi Baraka e o tamanho de tuberculos foi com 0-20 mm. A data de plantio foi 25.09.1990. Plantarémos em cada vaso 3-3 tuberculos com embaixo de 4cm de superficie da mistura no vasos. Irrigarémos com 12 mm quantidade da augua 2 vezes por semana. Para produção aplicarémos sistema de proteção de plantas como usados no Brasíl. Ambiente foi controlado ventilação automatizado. Temperatura médio foi 21 0C é humidade médio foi 66% durante de experimento. A data de colheta foi 14.12.1990. As pesagens foram feitos como peso fresco e matéria seca. Os resultados foram submetidos a analise de variáncia, MANOVA. Os manejos foram como a seguir no Tabela 3. Resultados e Discuscáo Experimento 1. Efeito de diferentes misturas para produção da batata semente pré- básica em casa de vegetação O tratamento 3. i.e.: mistura de 80% latossolo vermelho novo, 10% palha de arroz queimado e 10% esterco de curral, apresentou os maiores valores para numero de tuberculos com 0-20 mm (tamanho de comercial), peso de tuberculos com 0-20 mm e peso total de tuberculos por vaso. Porém, não houve diferencas significativas para o numero tuberculos comerciais, i.e.: com 0-20 mm, para os tratamentos 2., 3., 4., e 5. Portanto, a mistura poderá ter uma composição entre 60 a 90% de latossolo vermelho novo, 6 a 24% de palha de arroz queimado e de 4 a 16% de esterco de curral. Não houve diferenca significativa entre a mistura padrão utilizada e as misturas incluidas nos extremos indicados anteriormente. Porém, a mistura padrão recebeu adubação quimica de 4N:14P:8K (3.6 grama vaso-1) e calcário na dosagem de 4.2 grama vaso-1, o que não aconteceu com as parcelas das misturas em analise. Experimento 2. Efeito de adubo 4N:14P:8K para produção da batata semente pré- básica em casa de vegetação Há um efeito crescente das dóses de 4N:14P:8K nos caracteres observados. Porém, a maior dóse não chegou a ultrapassar a mistura padrão. Experimento 3. Efeito de latossolo vermelho novo, palha de arroz queimado e adubo 4N:14P:8K para produção da batata semente pré- básica em casa de vegetação Efeitos de misturas As duas misturas (i.e.: 1 e 2) deram resultados significativos mais alto que a mistura padrão, em média 54 %. Entre as misturas 1 e 2, foi melhor a 2. (80% latossolo vermelho novo, 10% palha de arroz queimado, 10% esterco de curral). Examinando-se 15 fatores, entre 11 casos afirmou-se a mistura como para melhor que a mistura 1. (70% latossolo vermelho novo, 20% palha de arroz queimado, 10% esterco de curral). Em caso de número de tuberculos 0-20 mm com a mistura 2. foi possivel aumentar geralmente os números de tuberculos em 77% que a mistura padrão. Efeitos de adubação 1. Área da folhas por planta entre manejo foi melhor de modo significativo a doságem de 3.6 grama vaso-1 adubo complexo (3103 cm2 plantas-1). 2. Peso fresco da folhas e de hastes por plantas as tendencias foram parecidos com o da área de folhas. 3. Peso fresco de raizis por planta até 7.2 grama vaso-1 diminuiu depois aumentou. 4. Peso fresco total de tuberculos por planta as crescentes doságens de um modo forte diminuiram a produção de tuberculos de 0 e 18.0 grama vaso-1 em 160% em os dois caso da mistura. 5. Peso de fitomassa fresco por planta foi melhor a 3.6 g vaso-1 (239 grama planta-1 em médio da dois mistura), depois os dados diminuirám. 6. Produção de biomassa fresco por planta a maxima produção (188 grama planta-1) foi obtida com 3.6 grama vaso-1. Deste ponto de modo forte caiu a produção. 7. Peso da matéria seca de folhas, hastes e raizis por planta somente em caso de mistura padrão o resultado foi significativo em relação aos outros tratamentos. 8. Péso da matéria seca de tuberculos total por planta modo significativo diminuiu a produção (0 e 18.0 grama vaso-1 = 360%) em médio da duas misturas. 9. Biomassa produção de materia seca por planta modo significativo diminuiu para efeito de alta dosagens de adubo complexo (0 e 18.0 grama vaso-1 = 158%) em médio da duas misturas. 10. Peso fresco de tuberculos com 0-20 mm as crescentes dosagens de 0 e 18.0 grama vaso-1 diminuiram a produção em 213% em médio da duas misturas. 11. Peso fresco de tuberculos com 20 mm-1 as crescentes dosagens de 0 e 18.0 grama vaso-1 diminuiram a produção assima de 250% em médio da duas misturas. 12. Numero de tuberculos 0-20 mm e 20 mm- por planta com os manejos de 0 e 18.0 grama vaso-1 foi possível aumentar em media 200% sobre a mistura padrão. Os manejo de 18.0 grama de adubo vaso-1 já causaram importante diminuição em relação caso a absoluto controle. 13. Numero total de tuberculos por planta entre manejos foi melhor a dosagem de 7.2 grama vaso-1 adubo complexo 4N:14P:8K comparando da mistura padrão. Nos verificamos-se que a mistura padrão sempre deu menor rasultados do que as outras misturas (i.e.: 1 e 2). Entre as misturas 1 e 2 a melhor foi a número 2. (80% latossolo vermelho novo, 10% palha de arroz queimado, 10% esterco de curral). Com esta mistura e com relação a mistura padrão, foi possível aumentar o número de tuberculos 0-20 mm com 77%. No caso do adubação, verificamos que grande quantidades de adubo acima de 7.2 grama vaso-1, de modo rigoroso diminuiu a produção de batata-semente pré- básica. Este fato deve ser considerado para a eleição das dosagens de adubos. Deve-se indicar o caso de número de tuberculos acima 20 mm-, onde em relação mistura padrão foi possivel aumentar em média 73% os resultados. Reconhecimento: Esta pesquisa foi apoio da Empresa Brasileira de Pesquisa Agropecuaria- Centro Nacional de Pesquisas de Hortaliças, Brasília-DF e Centro Pesquisa de Solo e Agroquímica do Academia Húngara de Ciências, Budapest References Kádár I-Márton L.-Horváth S. 2000. Mineral fertilisation of potato (Solanum tuberosum L.) on calcareous chernozem soil. Plant Production. 49: 291-306. Kurnik E.-Németh T.-Márton L.-Radimszki L. 2001. Effects of a new environment friendly deep fertilization system on a limy chernozem soil parameters. Agrochemistry and Soil Science. Budapest. In press László M. 2000. Nutrition of potato (Solanum tuberosum L.) on Hungary on a chernozem soil. Acta Agronomica Óváriensis. 42: 81-93. László M. 2001a. Climate change and N, P, K, Mg fertilization effects on potato (Solanum tuberosum L.) yield and quality. EAPR. Hamburg. In press László M. 2001b. Year and fertilization effect analysis in long field term experiments. XLIII. Georgikon Days. University of Veszprém. Keszthely László M.-Imre K.-Jose E.M. 2000a. Effects of Crotalaria juncea L. and Crotalaria spectabilis ROTH. on soil fertility and soil conservation in Hungary. Acta Agronomica Óváriensis. 42: 99-106. László M.-Silva J.C.-Jose A.B. 2000b. Ecological friendly dragée technics on different crops and vegetables seeds. Acta Agronomica Óváriensis. 42: 107-111. László M.-Silva J.B.C.-Jose A.B. 2000c. Ecological friendly dragée technics to sustainable precision agriculture. Fertilization in the Third Millenium. CASISCF. Beijing Márton L. 2000a. Effects of NPK fertilizers on potato (Solanum tuberosum L.) yield. Doctoral Ph.D Dissertation. University of Veszprém, Keszthely Márton L. 2000b. Effects of NPK fertilizers on potato (Solanum tuberosum L.) yield. Doctoral Ph.D Thesis. University of Veszprém, Keszthely Márton L. 2001a. Climete change effets on rye (Secale cereale L.) yield. Agrochemistry and Soil Science. Budapest. In press Márton L. 2001b. Climate change and fertilization effect analysis at the Tisza- river basin on rye yield. SZINET. University of Szent István. Gödöllő Márton L.-Kádár I.-Estáquio M.J. 2000. Effects of Crotalaria juncea L. and Crotalaria spectabilis ROTH on soil fertility and soil conservation. ESSC. Man and Soil at the Third Millennium. Abstract Book. 195. Valencia Reifschneider F.J.B. 1987. Produção de batata. Linha Gráfica e Editora. Brasília. p. 239. Tabela 1. Tratamentos do experimento 1. (Brasília-DF, 1990) ------------------------------------------------------------------ Numero de Composição em % Tratamento Solo novo Palha de arroz queimado Esterco de curral ------------------------------------------------------------------ 1. 100 0 0 2. 90 6 4 3. 80 10 10 4. 70 18 12 5. 60 24 16 6. 50 30 20 7. 40 36 24 ----------------------------------------------------------------- Tabela 2. Tratamentos do experimento 2. (Brasília-DF, 1990) ------------------------------------------------------- Numero de Adubo 4:14:8 N P2O5 K2O Tratamento Grama vaso-1 ------------------------------------------------------- 1. 0.0 0.000 0.000 0.000 2. 1.8 0.072 0.252 0.144 3. 3.6 0.144 0.504 0.288 4. 5.4 0.216 0.756 0.432 5. 7.2 0.288 1.008 0.576 6. 9.0 0.360 1.260 0.720 7. 10.8 0.432 1.512 0.864 8. 12.6 0.504 1.764 1.008 9. 14.4 0.576 2.016 1.152 ------------------------------------------------------- Tabela 3. Tratamentos do experimento 3. (Brasília-DF, 1990) ------------------------------------------------------------------------ Num. de Mistura % Trat. Solo novo Palea de arr. Q Esterco de curral 4N:14P:8K g vaso-1 ------------------------------------------------------------------------ 1. 70 20 10 0.0 2 70 20 10 3.6 3. 70 20 10 7.2 4. 70 20 10 10.8 5. 70 20 10 14.4 6. 70 20 10 18.0 7. 80 10 10 0.0 8. 80 10 10 3.6 9. 80 10 10 7.2 10. 80 10 10 10.8 11. 80 10 10 14.4 12. 80 10 10 18.0 ------------------------------------------------------------------------