New steps of elastography for the diagnosis of chronic pancreatitis

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Oxygen-Sensing Methods in Biomedicine from the Macroscale to the Microscale.

Oxygen monitoring has been a topic of exhaustive study given its central role in the biochemistry of life. The ability to quantify the physiological distribution and real-time dynamics of oxygen from sub-cellular to macroscopic levels is required to fully understand the mechanisms associated with both normal physiology and disease states. This Review will present the most significant recent advances in the development of oxygen-sensing materials and techniques, including polarographic, nuclear medicine, magnetic resonance, and optical approaches, that can be applied specifically for the real-time monitoring of oxygen dynamics in cellular and tissue environments. As some of the most exciting recent advances in synthetic methods and biomedical applications have been in the field of optical oxygen sensors, a major focus will be on the development of these toolkits.

Empleo de la medicina nuclear y las técnicas de imágenes en las afecciones del sistema óseo / Emploi de la médicine nucléaire et des techniques par image dans les affections du système osseux / Use of nuclear medicine and imaging techniques in disorders of the bone system

La medicina nuclear es la especialidad médica que se ocupa del diagnóstico, tratamiento e investigación médica mediante el uso de radioisótopos como fuentes abiertas. A menudo, las personas presentan diferentes condiciones patológicas óseas como la osteoporosis, el cáncer de hueso primario, las metástasis óseas, la artrosis y la artritis. Como objetivo de esta revisión se presentaron estadísticas internacionales y nacionales, y se evaluó la incidencia de esas afecciones. Además, se identificaron los radiofármacos más empleados en la actualidad para el diagnóstico y tratamiento de las enfermedades óseas, así como el uso combinado con las técnicas de imagen más utilizadas mediante la revisión de diferentes estudios clínicos. Se expuso la utilidad de la gammagrafía ósea para el diagnóstico y la confirmación de las afecciones estudiadas. Igualmente, se presentó el empleo de nuevas técnicas como las tomografías por emisión de fotón único o por emisión de positrones. Se observó que el radioisótopo más empleado para el diagnóstico de enfermedades del sistema óseo es el 99mTc por sus características físicas y químicas, mientras que para terapia se emplean 186Re, 188Re, 153Sm, 177Lu, 32P, 89Sr, 85Sr, 117mSn, según el tipo, ubicación y magnitud de las lesiones y la disponibilidad del radioisótopo. En la actualidad, el desarrollo de los radiofármacos se ha centrado en la combinación de estos radioisótopos con diferentes biomoléculas para mejorar sus propiedades y ampliar su campo de aplicaciones(AU)

Nuclear medicine is the medical specialty that deals with clinical diagnosis, treatment and research through the use of isotopes as open sources. Bone diseases such as osteoporosis, primary bone cancer, bone metastases, arthrosis and arthritis are common among the population. The objective of this review was to present international and national statistics, and evaluate the incidence of these disorders. Additionally, a review was conducted of various clinical studies to identify the radiopharmaceuticals most frequently used to diagnose and treat bone disease, and their combination with the most common imaging techniques. A presentation was made of the usefulness of bone gammagraphy and the confirmation of the disorders studied. Reference was also made to the use of new techniques such as single photon emission tomography or positron emission tomography. It was found that the radioisotope most commonly used to diagnose diseases of the bone system was 99mTc, due to its physical and chemical characteristics, whereas 186Re, 188Re, 153Sm, 177Lu, 32P, 89Sr, 85Sr, 117mSn are used for therapeutic purposes, depending on the type, location and magnitude of the lesions and the availability of the radioisotope. At present, radiopharmaceutical development centers on combining these radioisotopes with various biomolecules to improve their properties and broaden their field of application(A)

La médecine nucléaire est la spécialité médicale s'occupant du diagnostic, du traitement et de la recherche médicale au moyen de radioisotopes comme sources ouvertes. Les personnes sont souvent touchées par différentes conditions pathologiques osseuses telles que l'ostéoporose, le cancer d'os primaire, les métastases osseuses, l'arthrose, et l'arthrite. Le but de cette révision est de présenter des statistiques internationales et nationales, et d'évaluer l'incidence de ces affections. Grâce à la révision de différentes études cliniques, on a également identifié les traceurs isotopiques les plus souvent utilisés de nos jours pour le diagnostic et le traitement des maladies osseuses, ainsi que l'emploi combiné des techniques par image les plus fréquentes. L'utilité de la gammagraphie osseuse pour le diagnostic et la confirmation des affections étudiées a été mise en évidence. De nouvelles technologies telles que les tomographies par émission de photon unique ou par émission de positons a été également présentées. On a trouvé que le radioisotope le plus souvent utilisé pour le diagnostic des maladies du système osseux est le 99mTc, dû à ses caractéristiques physiques et chimiques, tandis que pour la thérapie, les 186Re, 188Re, 153Sm, 177Lu, 32P, 89Sr, 85Sr, et 117mSn sont utilisés selon le type, la localisation et la magnitude des lésions, et la disponibilité du radioisotope. Aujourd'hui, le développement des traceurs isotopiques est axé sur la combinaison de ces radioisotopes avec différentes biomolécules pour améliorer leurs propriétés et élargir leur champ d'applications(AU)

Isotope effect in the binding of tritium and 14C-labelled cortisol to corticosteroid-binding-globulin in serum.

We have determined the free cortisol concentration in serum using either the Amicon MPS-1 ultrafiltration-centrifugation method (I) or equilibrium dialysis (II). If procedure I was used we found that [1,2,6,7-3H]-, and [4-14C]cortisol had a lower affinity than unlabelled cortisol for corticosteroid binding globulin (CBG). The binding affinity (Ka) to three separate CBG-containing samples was 8-18 times lower for [1,2,6,7-3H]cortisol and 30-90 times lower for [4-14C]cortisol, when compared with that of unlabelled cortisol. This difference in affinity to CBG was not observed if method II was used for the free cortisol determinations. The observed isotope effect in method I is not caused by unspecific binding to material such as the Amicon MPS-1 chamber or to impurities in the tracer. We suggest that the centrifugation step during ultrafiltration changed the conformation of CBG, thereby reducing its affinity for labelled cortisol. It is concluded that incorrect results will be obtained if radiolabelled is cortisol used for determining the free cortisol content of plasma with the Amicon MPS-1 device.

Patient exposures to HIV during nuclear medicine procedures.

Although the potential for transmission of bloodborne pathogens to patients through transfusion of contaminated blood is well known, it is less widely recognized that such transmission can also occur during medical procedures involving withdrawal and reinjection of blood or blood products (e.g., nuclear medicine procedures). Since 1989, three patients (two in hospitals in the United States and one in the Netherlands) undergoing nuclear medicine procedures have been reported to have inadvertently received intravenous injections of blood or other material from patients infected with human immunodeficiency virus (HIV). Two of these patients are known to have become infected with HIV during these procedures; HIV test results are not available for the third patient. This report summarizes these three incidents and provides recommendations for preventive measures.

Hepatología nuclear

For many years the liver and spleen scan has been the study more frequently used by nuclear medicine, however recent advances in the functional evaluztion of the liver through the use of newer isotopes, make the colloid scan less useful. The real progress in nuclear medicine occurs in 1982 with the introduction of the iminodiacetic derivatives (HIDA) tagged with 99mTc. The initial compounds have several important limitations such as the hepatic function and the bilirubin levels, that now with the most recent derivatives such as the mebromofenin (TMB) became less important. This compound has many advantages such as high hepatic concentration (98.1 percent), rapid excretion (ti/2:16 minutes) and great resistance to displacement by bilirubin (70 percent with levels above 20 mgpercent). All these reasons make TMB the ideal agent to study the hepatobiliary physiology. HIDA scan is the most reliable of all the imaging modalities available in the diagnosis of acute cholecystitis with a sensitivity of 92-100 percent, and a specificity of 95-98 percent. The diagnosis of chronic cholecystitis is also simple by this method. Other indications of the HIDA scan is in the study of biliary obstructions, evaluation of biliodigestive anastomosis, biliary fistulas, hepato-biliary ruptures and congenital abnormalities such as choledochal cysts. One of the most important aspect of this technic, is the ability to study hepatic function through the use of the computer and special curves, that allows a direct evaluation of the different steps of hepatic function (uptake, excretion). The function of the transplanted liver can be evaluated this way, and modern Hepatology consider this modality as a very important diagnostic tool.