963 resultados para 2,4-DICHLOROPHENOXYACETIC ACID 2,4-D


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BACKGROUND Detecting prostate cancer before spreading or predicting a favorable therapy are challenging issues for impacting patient's survival. Presently, 2-[(18) F]-fluoro-2-deoxy-D-glucose ((18) F-FDG) and/or (18) F-fluorocholine ((18) F-FCH) are the generally used PET-tracers in oncology yet do not emphasize the T877A androgen receptor (AR) mutation being exclusively present in cancerous tissue and escaping androgen deprivation treatment. METHODS We designed and synthesized fluorinated 5α-dihydrotestosterone (DHT) derivatives to target T877A-AR. We performed binding assays to select suitable candidates using COS-7 cells transfected with wild-type or T877A AR (WT-AR, T877A-AR) expressing plasmids and investigated cellular uptake of candidate (18) F-RB390. Stability, biodistribution analyses and PET-Imaging were assessed by injecting (18) F-RB390 (10MBq), with and without co-injection of an excess of unlabeled DHT in C4-2 and PC-3 tumor bearing male SCID mice (n = 12). RESULTS RB390 presented a higher relative binding affinity (RBA) (28.1%, IC50  = 32 nM) for T877A-AR than for WT-AR (1.7%, IC50  = 357 nM) related to DHT (RBA = 100%). A small fraction of (18) F-RB390 was metabolized when incubated with murine liver homogenate or human blood for 3 hr. The metabolite of RB390, 3-hydroxysteroid RB448, presented similar binding characteristics as RB390. (18) F-RB390 but not (18) F-FDG or (18) F-FCH accumulated 2.5× more in COS-7 cells transfected with pSG5AR-T877A than with control plasmid. Accumulation was reduced with an excess of DHT. PET/CT imaging and biodistribution studies revealed a significantly higher uptake of (18) F-RB390 in T877A mutation positive xenografts compared to PC-3 control tumors. This effect was blunted with DHT. CONCLUSION Given the differential binding capacity and the favorable radioactivity pattern, (18) F-RB390 represents the portrayal of the first imaging ligand with predictive potential for mutant T877A-AR in prostate cancer for guiding therapy. Prostate 75:348-359, 2015. © 2014 Wiley Periodicals, Inc.

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Question: The intervertebral disc (IVD) has a limited regenerative potential and low back pain represents a leading cause of disability [1]. IVD repair strategies require an appropriate cell source that is able to regenerate the damaged tissue such as progenitor stem cells. Recently, progenitor cells that are positive for the angiopoietin re- ceptor (Tie2) in the nucleus pulposus were identified [2]. Here we isolated primary cells from bovine IVD and sorted bovine nucleus pulposus progenitor cells (NPPC) for the marker Tie2. Furthermorewe tested whether Tie2 expressing cells can differentiate into os- teogenic and adipogenic lineages in vitro. Methods: NP cells were obtained from 1 year old bovine tails by sequential digestion with pronase for 1 h and collagenase over- night. Sorted Tie2- and Tie2+ cells were cultured in osteogenic and adipogenic medium for 3 weeks. The formed cell layers from both subpopulations were stained for calcium deposition and fat droplets. Colony forming units were prepared for both cell sus- pensions in methylcellulose-based medium and formed colonies ([10 cells) were analyzed macroscopically after 8 days. Results: After 3 weeks of culture, sorted Tie2+ cells were able to differentiate into osteocytes and adipocytes as characterized by cal- cium deposition and fat droplet formation. By contrast, Tie2- cells generated a weak staining for calcium and no fat droplets were ob- tained (Fig. 1). Sorted Tie2- and Tie2+ subpopulations of cells both formed colonies, however with different morphologies. The colonies formed from Tie2+ cells were spheroid in shape whereas those from Tie2- cells were spread and fibroblastic. Conclusion: Our data showed that Tie2+ cells of the nucleus pul- posus cells are progenitor-like cells that are able to differentiate into osteogenic and adipogenic lineages. Sorting of NPPC for Tie2 may represent a promising strategy with the potential to be used in the clinics for treatment of intervertebral disc damage. References 1. Freemont AJ (2009) The cellular pathobiology of the degenerate intervertebral disc and discogenic back pain. Rheumatology (Oxford) 48:5–10 2. Sakai D, Nakamura Y, Nakai T et al (2012) Exhaustion of nucleus pulposus progenitor cells with ageing and degeneration of the intervertebral disc. Nat Commun 3:1264 Acknowledgments: This project was funded by two projects of the Swiss National Science Foundation grant number #IZK0Z3_154384 and #310030_153411.

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Sodium/hydrogen exchangers (NHEs) are ubiquitous ion transporters that serve multiple cell functions. We have studied two mammalian isoforms, NHE1 (ubiquitous) and NHE3 (epithelial-specific), by measuring extracellular proton (H+) gradients during whole-cell patch clamp with perfusion of the cell interior. Maximal Na(+)-dependent H+ fluxes (JH+) are equivalent to currents >20 pA for NHE1 in Chinese hamster ovary fibroblasts, >200 pA for NHE1 in guinea pig ventricular myocytes, and 5-10 pA for NHE3 in opossum kidney cells. The fluxes are blocked by an NHE inhibitor, ethylisopropylamiloride, and are absent in NHE-deficient AP-1 cells. NHE1 activity is stable with perfusion of nonhydrolyzable ATP [adenosine 5'-(beta,gamma-imido)triphosphate], is abolished by ATP depletion (2 deoxy-D-glucose with oligomycin or perfusion of apyrase), can be restored with phosphatidylinositol 4,5-bisphosphate, and is unaffected by actin cytoskeleton disruption (latrunculin or pipette perfusion of gelsolin). NHE3 (but not NHE1) is reversibly activated by phosphatidylinositol 3,4,5-trisphosphate. Both NHE1 and NHE3 activities are disrupted in giant patches during gigaohm seal formation. NHE1 (but not NHE3) is reversibly activated by cell shrinkage, even at neutral cytoplasmic pH without ATP, and inhibited by cell swelling. NHE1 in Chinese hamster ovary fibroblasts (but not NHE3 in opossum kidney cells) is inhibited by agents that thin the membrane (L-alpha-lysophosphatidylcholine and octyl-beta-D-glucopyranoside) and activated by cholesterol enrichment, which thickens membranes. Expressed in AP-1 cells, however, NHE1 is insensitive to these agents but remains sensitive to volume changes. Thus, changes of hydrophobic mismatch can modulate NHE1 but do not underlie its volume sensitivity.

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This in vivo study aimed to evaluate the influence of contact points on the approximal caries detection in primary molars, by comparing the performance of the DIAGNOdent pen and visual-tactile examination after tooth separation to bitewing radiography (BW). A total of 112 children were examined and 33 children were selected. In three periods (a, b, and c), 209 approximal surfaces were examined: (a) examiner 1 performed visual-tactile examination using the Nyvad criteria (EX1); examiner 2 used DIAGNOdent pen (LF1) and took BW; (b) 1 week later, after tooth separation, examiner 1 performed the second visual-tactile examination (EX2) and examiner 2 used DIAGNOdent again (LF2); (c) after tooth exfoliation, surfaces were directly examined using DIAGNOdent (LF3). Teeth were examined by computed microtomography as a reference standard. Analyses were based on diagnostic thresholds: D1: D 0 = health, D 1 –D 4 = disease; D2: D 0 , D 1 = health, D 2 –D 4 = disease; D3: D 0 –D 2 = health, D 3 , D 4 = disease. At D1, the highest sensitivity/specificity were observed for EX1 (1.00)/LF3 (0.68), respectively. At D2, the highest sensitivity/ specificity were observed for LF3 (0.69)/BW (1.00), respectively. At D3, the highest sensitivity/specificity were observed for LF3 (0.78)/EX1, EX2 and BW (1.00). EX1 showed higher accuracy values than LF1, and EX2 showed similar values to LF2. We concluded that the visual-tactile examination showed better results in detecting sound surfaces and approximal caries lesions without tooth separation. However, the effectiveness of approximal caries lesion detection of both methods was increased by the absence of contact points. Therefore, regardless of the method of detection, orthodontic separating elastics should be used as a complementary tool for the diagnosis of approximal noncavitated lesions in primary molars.

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Introduction: Although it seems plausible that sports performance relies on high-acuity foveal vision, it could be empirically shown that myoptic blur (up to +2 diopters) does not harm performance in sport tasks that require foveal information pick-up like golf putting (Bulson, Ciuffreda, & Hung, 2008). How myoptic blur affects peripheral performance is yet unknown. Attention might be less needed for processing visual cues foveally and lead to better performance because peripheral cues are better processed as a function of reduced foveal vision, which will be tested in the current experiment. Methods: 18 sport science students with self-reported myopia volunteered as participants, all of them regularly wearing contact lenses. Exclusion criteria comprised visual correction other than myopic, correction of astigmatism and use of contact lenses out of Swiss delivery area. For each of the participants, three pairs of additional contact lenses (besides their regular lenses; used in the “plano” condition) were manufactured with an individual overcorrection to a retinal defocus of +1 to +3 diopters (referred to as “+1.00 D”, “+2.00 D”, and “+3.00 D” condition, respectively). Gaze data were acquired while participants had to perform a multiple object tracking (MOT) task that required to track 4 out of 10 moving stimuli. In addition, in 66.7 % of all trials, one of the 4 targets suddenly stopped during the motion phase for a period of 0.5 s. Stimuli moved in front of a picture of a sports hall to allow for foveal processing. Due to the directional hypotheses, the level of significance for one-tailed tests on differences was set at α = .05 and posteriori effect sizes were computed as partial eta squares (ηρ2). Results: Due to problems with the gaze-data collection, 3 participants had to be excluded from further analyses. The expectation of a centroid strategy was confirmed because gaze was closer to the centroid than the target (all p < .01). In comparison to the plano baseline, participants more often recalled all 4 targets under defocus conditions, F(1,14) = 26.13, p < .01, ηρ2 = .65. The three defocus conditions differed significantly, F(2,28) = 2.56, p = .05, ηρ2 = .16, with a higher accuracy as a function of a defocus increase and significant contrasts between conditions +1.00 D and +2.00 D (p = .03) and +1.00 D and +3.00 D (p = .03). For stop trials, significant differences could neither be found between plano baseline and defocus conditions, F(1,14) = .19, p = .67, ηρ2 = .01, nor between the three defocus conditions, F(2,28) = 1.09, p = .18, ηρ2 = .07. Participants reacted faster in “4 correct+button” trials under defocus than under plano-baseline conditions, F(1,14) = 10.77, p < .01, ηρ2 = .44. The defocus conditions differed significantly, F(2,28) = 6.16, p < .01, ηρ2 = .31, with shorter response times as a function of a defocus increase and significant contrasts between +1.00 D and +2.00 D (p = .01) and +1.00 D and +3.00 D (p < .01). Discussion: The results show that gaze behaviour in MOT is not affected to a relevant degree by a visual overcorrection up to +3 diopters. Hence, it can be taken for granted that peripheral event detection was investigated in the present study. This overcorrection, however, does not harm the capability to peripherally track objects. Moreover, if an event has to be detected peripherally, neither response accuracy nor response time is negatively affected. Findings could claim considerable relevance for all sport situations in which peripheral vision is required which now needs applied studies on this topic. References: Bulson, R. C., Ciuffreda, K. J., & Hung, G. K. (2008). The effect of retinal defocus on golf putting. Ophthalmic and Physiological Optics, 28, 334-344.

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We describe and test a nonperturbatively improved single-plaquette lattice action for 4-d SU(2) and SU(3) pure gauge theory, which suppresses large fluctuations of the plaquette, without requiring the naive continuum limit for smooth fields. We tune the action parameters based on torelon masses in moderate cubic physical volumes, and investigate the size of cut-off effects in other physical quantities, including torelon masses in asymmetric spatial volumes, the static quark potential, and gradient flow observables. In 2-d O(N) models similarly constructed nearest-neighbor actions have led to a drastic reduction of cut-off effects, down to the permille level, in a wide variety of physical quantities. In the gauge theories, we find significant reduction of lattice artifacts, and for some observables, the coarsest lattice result is very close to the continuum value. We estimate an improvement factor of 40 compared to using the Wilson gauge action to achieve the same statistical accuracy and suppression of cut-off effects.

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von Karl Friedrich Tannert

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Grossmann, Henrik: "The Nature of Economic Crisis". Typoskript, 4 Blatt; Über die Tätigkeiten des Institutes für Sozialforschung. Verschiedene Berichte. 1940- 1941; "Report to the Trustees of the Kurt Gerlach Memorial Foundation". 25.01.1940, Typoskript, 5 Blatt; "Manuskript under preparation". Januar 1940, handschriftliche Liste, 1 Blatt; Horkheimer, Max: "Über die allgemeine Lage des Instituts". Bericht für das Advisory Bord (New York members) Meeting, 22.04.1940; sowie ein Protokoll des Treffens, Typoskript, 5 Blatt; "Annual Report on the Activities of the Société International de Recherces Sociales, Presented to the Eight General Meeting in New York City on April 27, 1940"; sowie "Report on the Activities of the International Institute of Social Research for the Year 1939". Typoskript, 13 Blatt; "Report to the Trustees of the Kurt Gerlach Memorial Foundation". 23.02.1941, Typoskript mit eigenhändigen Ergänzungen von Max Horkheimer und handschriftlichen Ergänzungen und Korrekturen von Leo Löwenthal, 7 Blatt; Liste der Veröffentlichungen und der Forschungsgebiete des Instituts für Sozialforschung; "Content of Periodicals. List of Articles and Selected Major Book Reviews Arranged According to Contibutors. List of Articles and Selected Major Book Reviews Arranged According Topics. 1934-1941". a) Typoskript, 14 Blatt; b) Typoskript , 15 Blatt; "Literatur über features". 03.02.1941, Veröffentlichungsliste, 1 Blatt; Veröffentlichungsliste zu den Gebieten Nationalsozialismus, Massenkultur, Sozialgeschichte des späteren Mittelalters; 19.12.1941, Typoskript, 1 Blatt; Ankündigung und Übersicht über die ersten Nummern der "Studies in Philosophy and Social Science". 1941; Typoskripte und Drucksachen, 3 Blatt; "Supplementary Memorandum on the Activities of the Institute from 1939 to 1941. (supplemented to December, 1942)". 1942, als Typoskript vervielfältigt, 5 Blatt; Über Organisation und Mitarbeiter des Institutes für Sozialforschung. 1943; a) Typoskript, 6 Blatt; b) Typoskript, 7 Blatt; c) Teilstück, Typoskript mit handschriftlichen Korrekturen, 2 Blatt; d) Teilstück, Typoskript, 3 Blatt; e) Entwurf, Typoskript mit handschriftlichen Korrekturen, 8 Blatt; "Annual Report on the Activities of the Social Studies Association, Inc.". 15.05.1943, Typoskript, 6 Blatt; "Statement of Prof. Dr. Max Horkheimer, Director of the Institut of Social Research on June 9, 1943. Reponse: Certain Charges made against the Institut of Social Research (Columbia University)". 1943; a) Typoskript, 6 Blatt; b) Typoskript mit handschriftlichen Randbemerkungen, 6 Blatt; c) deutsche Rückübersetzung, 1969, Typoskript mit handschriftlichen Korrekturen, 4 Blatt;

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Institute of Social Research: "Project on Antisemitism. Report to the American Jewish Committee on the first year of the Project ending March 15, 1944" (April 1944), a) Typoskript, 153 Blatt, b) Teilstück, Typoskript mit handschriftlichen Korrekturen, 22 Blatt, c) Entwurf der Gliederung, 16.11.1943, Typoskript, 2 Blatt, d) "Annex 1: List of Contributors to the Project on Antisemitism", Typoskript, 3 Blatt; "Notes on the latest phase of Nazi Antisemitism" (12.5.1944), a) Typoskript mit handschriftlichen Korrekturen und Ergänzungen, 4 Blatt, b) Typoskript, 3 Blatt;

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Objective. Itraconazole is recommended life-long for preventing relapse of disseminated histoplasmosis in HIV-infected patients. I sought to determine if serum itraconazole levels are affected by the type of Highly Active Anti-Retroviral Therapy (NNRTI or PI) being taken concomitantly to treat HIV. ^ Design. Retrospective cohort. ^ Methods. De-identified data were used from an IRB-approved parent study which identified patients on HAART and maintenance itraconazole for confirmed disseminated histoplasmosis between January 2003 and December 2006. Available itraconazole blood levels were abstracted as well as medications taken by each patient at the time of the blood tests. Mean itraconazole levels were compared using the student's t-test. ^ Results. 11 patients met study criteria. Patient characteristics were: median age 36, 91% men, 18% white, 18% black, 55% Hispanic and 9% Asians, median CD4 cell count 120 cells/mm3. 14 blood levels were available for analysis—8 on PI, 4 on NNRTI and 2 on both. 8/8 itraconazole levels obtained while taking concomitant PI were therapeutic (>0.4 μg/mL) in contrast to 0/4 obtained while taking NNRTI. Two patients switched from NNRTI to PI and reached therapeutic levels. Mean levels on NNRTI (0.05 μg/mL, s.d. 0.0) and on PI (2.45 μg/mL, s.d. 0.21) for these two patients were compared via a paired t-test (t = 16.00, d.f. = 1, P = 0.04). Remaining patient levels were compared using an unpaired t-test. Mean itraconazole on concomitant PI (n = 6) was 1.37 μg/mL (s.d. 0.74), while the mean on concomitant NNRTI was 0.05 μg/mL (s.d. 0.0), t = 2.39, d.f. = 6, P = 0.05. ^ Conclusions. Co-administration of NNRTI and itraconazole results in significant decreases in itraconazole blood levels, likely by inducing the CYP3A4 enzyme system. Itraconazole drug levels should be monitored in patients on concomitant NNRTI. PI-based HAART may be preferred over NNRTI-based HAART when using itraconazole to treat HIV-infected patients with disseminated histoplasmosis. ^

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Children who experience early pubertal development have an increased risk of developing cancer (breast, ovarian, and testicular), osteoporosis, insulin resistance, and obesity as adults. Early pubertal development has been associated with depression, aggressiveness, and increased sexual prowess. Possible explanations for the decline in age of pubertal onset include genetics, exposure to environmental toxins, better nutrition, and a reduction in childhood infections. In this study we (1) evaluated the association between 415 single nucleotide polymorphisms (SNPs) from hormonal pathways and early puberty, defined as menarche prior to age 12 in females and Tanner Stage 2 development prior to age 11 in males, and (2) measured endocrine hormone trajectories (estradiol, testosterone, and DHEAS) in relation to age, race, and Tanner Stage in a cohort of children from Project HeartBeat! At the end of the 4-year study, 193 females had onset of menarche and 121 males had pubertal staging at age 11. African American females had a younger mean age at menarche than Non-Hispanic White females. African American females and males had a lower mean age at each pubertal stage (1-5) than Non-Hispanic White females and males. African American females had higher mean BMI measures at each pubertal stage than Non-Hispanic White females. Of the 415 SNPs evaluated in females, 22 SNPs were associated with early menarche, when adjusted for race ( p<0.05), but none remained significant after adjusting for multiple testing by False Discovery Rate (p<0.00017). In males, 17 SNPs were associated with early pubertal development when adjusted for race (p<0.05), but none remained significant when adjusted for multiple testing (p<0.00017). ^ There were 4955 hormone measurements taken during the 4-year study period from 632 African American and Non-Hispanic White males and females. On average, African American females started and ended the pubertal process at a younger age than Non-Hispanic White females. The mean age of Tanner Stage 2 breast development in African American and Non-Hispanic White females was 9.7 (S.D.=0.8) and 10.2 (S.D.=1.1) years, respectively. There was a significant difference by race in mean age for each pubertal stage, except Tanner Stage 1 for pubic hair development. Both Estradiol and DHEAS levels in females varied significantly with age, but not by race. Estradiol and DHEAS levels increased from Tanner Stage 1 to Tanner Stage 5.^ African American males had a lower mean age at each Tanner Stage of development than Non-Hispanic White males. The mean age of Tanner Stage 2 genital development in African American and Non-Hispanic White males was 10.5 (S.D.=1.1) and 10.8 (S.D.=1.1) years, respectively, but this difference was not significant (p=0.11). Testosterone levels varied significantly with age and race. Non-Hispanic White males had higher levels of testosterone than African American males from Tanner Stage 1-4. Testosterone levels increased for both races from Tanner Stage 1 to Tanner Stage 5. Testosterone levels had the steepest increase from ages 11-15 for both races. DHEAS levels in males varied significantly with age, but not by race. DHEAS levels had the steepest increase from ages 14-17. ^ In conclusion, African American males and females experience pubertal onset at a younger age than Non-Hispanic White males and females, but in this study, we could not find a specific gene that explained the observed variation in age of pubertal onset. Future studies with larger study populations may provide a better understanding of the contribution of genes in early pubertal onset.^

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This is the seventeenth of a series of symposia devoted to talks by students about their biochemical engineering research. The first, third, fifth, ninth, twelfth, and sixteenth were at Kansas State University, the second and fourth were at the University of Nebraska-Lincoln, the sixth was in Kansas City and was hosted by Iowa State University, the seventh, tenth, thirteenth, and seventeenth were at Iowa State University, the eighth and fourteenth were at the University of Missouri–Columbia, and the eleventh and fifteenth were at Colorado State University. Next year's symposium will be at the University of Colorado. Symposium proceedings are edited by faculty of the host institution. Because final publication usually takes place elsewhere, papers here are brief, and often cover work in progress. ContentsThe Effect of Polymer Dosage Conditions on the Properties of ProteinPolyelectrolyte Precipitates, K. H. Clark and C. E. Glatz, Iowa State University An Immobilized Enzyme Reactor/Separator for the Hydrolysis of Casein by Subtilisin Carlsberg, A. J. Bream, R. A. Yoshisato, and G. R. Carmichael, University of Iowa Cell Density Measurements in Hollow Fiber Bioreactors, Thomas Blute, Colorado State University The Hydrodynamics in an Air-Lift Reactor, Peter Sohn, George Y. Preckshot, and Rakesh K. Bajpai, University of Missouri–Columbia Local Liquid Velocity Measurements in a Split Cylinder Airlift Column, G. Travis Jones, Kansas State University Fluidized Bed Solid Substrate Trichoderma reesei Fermentation, S. Adisasmito, H. N. Karim, and R. P. Tengerdy, Colorado State University The Effect of 2,4-D Concentration on the Growth of Streptanthus tortuosis Cells in Shake Flask and Air-Lift Permenter Culture, I. C. Kong, R. D. Sjolund, and R. A. Yoshisato, University of Iowa Protein Engineering of Aspergillus niger Glucoamylase, Michael R. Sierks, Iowa State University Structured Kinetic Modeling of Hybidoma Growth and Monoclonal Antibody Production in Suspension Cultures, Brian C. Batt and Dhinakar S. Kampala, University of Colorado Modelling and Control of a Zymomonas mobilis Fermentation, John F. Kramer, M. N. Karim, and J. Linden, Colorado State University Modeling of Brettanomyces clausenii Fermentation on Mixtures of Glucose and Cellobiose, Max T. Bynum and Dhinakar S. Kampala, University of Colorado, Karel Grohmann and Charles E. Yyman, Solar Energy Research Institute Master Equation Modeling and Monte Carlo Simulation of Predator-Prey Interactions, R. 0. Fox, Y. Y. Huang, and L. T. Fan, Kansas State University Kinetics and Equilibria of Condensation Reactions Between Two Different Monosaccharides Catalyzed by Aspergillus niger Glucoamylase, Sabine Pestlin, Iowa State University Biodegradation of Metalworking Fluids, S. M. Lee, Ayush Gupta, L. E. Erickson, and L. T. Fan, Kansas State University Redox Potential, Toxicity and Oscillations in Solvent Fermentations, Kim Joong, Rakesh Bajpai, and Eugene L. Iannotti, University of Missouri–Columbia Using Structured Kinetic Models for Analyzing Instability in Recombinant Bacterial Cultures, William E. Bentley and Dhinakar S. Kompala, University of Colorado

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Introducción: La utilización de regímenes de tratamiento más individualizados requiere de mejores sistemas de estratificación temprana en Linfoma Hodgkin (LH). El estudio Tomografía por Emisión de Positrones utilizando 2-[18F] fluoro-2-deoxi-Dglucosa (FDG-PET) intra-tratamiento podría jugar un rol muy importante en esta evaluación. Objetivo: Determinar el valor pronóstico del FDG-PET intra-tratamiento en pacientes con LH para predecir sobrevida libre de progresión y sobrevida global. Material y método: El estudio fue llevado a cabo en el Servicio de Hematología del Hospital Central de Mendoza incluyendo pacientes con diagnóstico de LH confirmados por histología. De acuerdo al estadio y sitio de presentación, los pacientes recibieron quimioterapia sola o la combinación de radioterapia y quimioterapia, con el uso del esquema ABVD (adriamicina, bleomicina, vinblastina y dacarbazina) como protocolo estándar. Los estudios FDG-PET fueron practicados como parte de la evaluación intra-tratamiento y a la finalización. Resultados: En total fueron evaluados 8 pacientes, Sexo: F/M: 4/4, Edad: 18-58 años (Mediana: 29 años), Estadios: IIB:1, IIIA:2, IIIB:1, IVA:1, IVB:3, regiones nodales: 2-10 (Mediana:4), compromiso extranodal: 4/8, síntomas B: 5/8, enfermedad bulky 2/8 . Subtipos: Escleronodular: 6/8, Celularidad mixta: 1/8, Depleción linfocítica: 1/8. IPS: 1: 3/8 2: 3/8 3: 1/8 4: 0/8 ≥ 5: 1/8. Tratamientos: ABVD x 6: 6/8, ABVD x 6 + Radioterapia: 2/8. PET intermedio: 8/8 negativos (6/8 PET 3, 2/8 PET 2). PET final: 7/8 PET negativo, 1/8 PET positivo. Recaída: 1/8 (10° mes). Seguimiento: 11-37 meses (mediana de 24 meses). Discusión y Conclusiones: Al momento actual el FDG-PET intra-tratamiento demostró tener un importante valor predictivo negativo dado que todos los pacientes, menos uno, se encuentran en remisión completa sin progresión de enfermedad. Resta aún determinar el rol que esta herramienta pueda tener en el futuro en la terapia adaptada al riesgo de pacientes con LH.

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We present field measurements of air-sea gas exchange by the radon deficit method that were carried out during JASIN 1978 (NE Atlantic) and FGGE 1979 (Equatorial Atlantic). Both experiments comprised repeated deficit measurements at fixed position over periods of days or longer, using a previously descibed precise and fast-acquiaition, automatic radon measuring system. The deficit time series exhibit variations that only partly reflect the expected changes in gas transfer. By evaluating averages over each time series we deduce the following gas transfer velocities (average wind velocity and water temperature in parentheses): JASIN phase 1: 1.6 ± 0.8 m/d (at ~6 m/s, 13°C) JASIN phase 2: 4.3 ± 1.2 m/d (at ~8 m/s, 13°C) FGGE: 1.2 ± 0.4 m/d (at ~5 m/s, 28°C) 0.9 ± 0.4 m/d (at ~7 m/s, 28°C) 1.5 ± 0.4 m/d (at ~7 m/s, 28°C) The large difference betwen the JASIN phase 2 and FGGE values despite quite similare average wind velocity becomes even larger when the values are, however, fully compatible with the range of gas transfer velocities observed in laboratory experiments and the conclusion is suggested that their difference is caused by the highly different wind variability in JASIN and FGGE. We conclude that in gas exchange parameterization it is not sufficinent to consider wind velocity only. A comparison of our observations with laboratory results outlines the range of variations of air-sea gas transfer velocities with wind velocity and sea state. We also reformulate the radon deficit method, in the light of our observed deficit variations, to account explicitely for non-stationary and horizontal inhomogeneity in previous radon work introduces considerable uncertainty in deduced gas transfere velocity. We furthermore discuss the observational rewuirements that have to be met for an adequate exploitation of the radon deficit method, of which an observation area of minimum horizontal inhomogeneity and monitoring of the remaining inhomogeneities are thought to be the most stringent ones.