Cationic liposomes in mixed didodecyldimethylammonium bromide and dioctadecyldimethylammonium bromide aqueous dispersions studied by differential scanning calorimetry, nile red fluorescence, and turbidity

The thermotropic phase behavior of cationic liposomes in mixtures of two of the most investigated liposome-forming double-chain lipids, dioctadecyldimethylammonium bromide (DODAB) and didodecyldimethylammonium bromide (DDAB), was investigated by differential scanning calorimetry (DSC), turbidity, and Nile Red fluorescence. The dispersions were investigated at 1.0 mM total surfactant concentration and varying DODAB and DDAB concentrations. The gel to liquid-crystalline phase transition temperatures (T-m) of neat DDAB and DODAB in aqueous dispersions are around 16 and 43 degrees C, respectively, and we aim to investigate the T-m behavior for mixtures of these cationic lipids. Overall, DDAB reduces the T-m of DODAB, the transition temperature depending on the DDAB content, but the T-m of DDAB is roughly independent of the DODAB concentration. Both DSC and fluorescence measurements show that, within the mixture, at room temperature (ca. 22 degrees C), the DDAB-rich liposomes are in the liquid-crystalline state, whereas the DODAB-rich liposomes are in the gel state. DSC results point to a higher affinity of DDAB for DODAB liposomes than the reverse, resulting in two populations of mixed DDAB/DODAB liposomes with distinctive phase behavior. Fluorescence measurements also show that the presence of a small amount of DODAB in DDAB-rich liposomes causes a pronounced effect in Nile Red emission, due to the increase in liposome size, as inferred from turbidity results.

Denisiuk-type reflection holography display with sillenite crystals for imaging and interferometry of small objects

A novel setup for imaging and interferometry through reflection holography with Bi12TiPO20(BTO) sillenite photorefractive crystals is proposed. A variation of the lensless Denisiuk arrangement was developed resulting in a compact, robust and simple interferometer. A red He-Ne laser was used as light source and the holographic recording occurred by diffusion with the grating vector parallel to the crystal [0 0 1]-axis. In order to enhance the holographic image quality and reduce noise a polarizing beam splitter (PBS) was positioned at the BTO input and the crystal was tilted around the [0 0 1]-axis. This enabled the orthogonally polarized transmission and diffracted beams to be separated by the PBS, providing the holographic image only. The possibility of performing deformation and strain analysis as well as vibration measurement of small objects was demonstrated. (C) 2007 Elsevier B.V. All rights reserved.

Reproductive ecology of the freshwater red alga Batrachospermum delicatulum (Batrachospermales, Rhodophyta) in three tropical streams

Batrachospermum delicatulum specimens from three stream segments were analyzed from a tropical region in south-eastern Brazil (20°18′- 20°49′S, 49°13′-49°46′W). Physical and chemical parameters and the spatial placement of thalli were investigated along with the reproductive characteristics of the gametophytic phase. Sequence data of the cox 2-3 spacer region was also utilized to evaluate genetic variation in individuals within and among stream segments. Gametophyte occurred under relatively diverse environmental conditions, whereas thalli abundance was weakly or not correlated to environmental variables within the stream segments. All specimens examined were dioecious. The ratio of male/female plants was relatively low (0.5 to 1.3) and male plants tended to occur as clumps (two or three plants together). High reproductive success was observed, as indicated by the occurrence of 100% fertilized (carposporophytic) female plants. This is similar to previous reports for this and other dioecious species, which is remarkable considering the relatively low proportion of male/female plants. Results support the two hypotheses to explain the high reproductive success in dioecious species. The occurrence of male plants in clumps was evidence for a strict spatial relationship (i.e. male plants located in upstream position of female plants in order to release spermatia, which would be carried by eddies through female plants). In contrast, the occurrence of male and female plants adjacent to each other allowed outcrossing among neighboring plants with intermingled male and female branches, which seemed more applicable to some situations (low turbulence habitats). The cox 2-3 spacer region from the 18 individuals sequenced was 376 bp and the DNA sequence was identical with no base pair substitutions. Likewise, a previous study of another Batrachospermum species showed that the same haplotypes were present in all stream segments from the same drainage basin, even though the stream segments were a considerable distance apart. Short distance dispersal either by small birds or waterway connectivity might explain these findings.

Modulation of the pharmacological effects of enzymatically-active PLA 2 by BTL-2, an isolectin isolated from the Bryothamnion triquetrum red alga

Background. An interaction between lectins from marine algae and PLA 2 from rattlesnake was suggested some years ago. We, herein, studied the effects elicited by a small isolectin (BTL-2), isolated from Bryothamnion triquetrum, on the pharmacological and biological activities of a PLA 2 isolated from rattlesnake venom (Crotalus durissus cascavella), to better understand the enzymatic and pharmacological mechanisms of the PLA 2 and its complex. Results. This PLA2 consisted of 122 amino acids (approximate molecular mass of 14 kDa), its pI was estimated to be 8.3, and its amino acid sequence shared a high degree of similarity with that of other neurotoxic and enzymatically-active PLA2s. BTL-2 had a molecular mass estimated in approximately 9 kDa and was characterized as a basic protein. In addition, BTL-2 did not exhibit any enzymatic activity. The PLA2 and BTL-2 formed a stable heterodimer with a molecular mass of approximately 24-26 kDa, estimated by molecular exclusion HPLC. In the presence of BTL-2, we observed a significant increase in PLA2 activity, 23% higher than that of PLA2 alone. BTL-2 demonstrated an inhibition of 98% in the growth of the Gram-positive bacterial strain, Clavibacter michiganensis michiganensis (Cmm), but only 9.8% inhibition of the Gram-negative bacterial strain, Xanthomonas axonopodis pv passiflorae (Xap). PLA2 decreased bacterial growth by 27.3% and 98.5% for Xap and Cmm, respectively, while incubating these two proteins with PLA2-BTL-2 inhibited their growths by 36.2% for Xap and 98.5% for Cmm. PLA2 significantly induced platelet aggregation in washed platelets, whereas BTL-2 did not induce significant platelet aggregation in any assay. However, BTL-2 significantly inhibited platelet aggregation induced by PLA2. In addition, PLA 2 exhibited strong oedematogenic activity, which was decreased in the presence of BTL-2. BTL-2 alone did not induce oedema and did not decrease or abolish the oedema induced by the 48/80 compound. Conclusion. The unexpected results observed for the PLA2-BTL-2 complex strongly suggest that the pharmacological activity of this PLA2 is not solely dependent on the presence of enzymatic activity, and that other pharmacological regions may also be involved. In addition, we describe for the first time an interaction between two different molecules, which form a stable complex with significant changes in their original biological action. This opens new possibilities for understanding the function and action of crude venom, an extremely complex mixture of different molecules. © 2008 Oliveira et al; licensee BioMed Central Ltd.

Cytogenetic description of the Amazonian brown brocket Mazama nemorivaga (Artiodactyla, Cervidae)

The Amazonian brown brocket Mazama nemorivaga (Cuvier, 1817) is a small to medium-sized deer from the Amazon rainforest and ecotones. The first karyotype described was 2n=67 to 69 + 2-7 B and FN= 69-72, in which all chromosomes were acrocentric and the X chromosome was the only submetacentric chromosome. However, important aspects of the species chromosome evolution were not resolved because of the lack of information on chromosome banding. The G-banding pattern of M. nemorivaga karyotype showedthe presence of an XX/XY1Y2 sex chromosome system as a product of an X-autosome tandem fusion, which results in a basic 2n=68, FN=70 in females and 2n= 69, FN=70 in males. The fact that this karyotype only differs from that of Capreolus capreolus pygargus (Pallas, 1771; 2n=70, FN=72+B) by X-autosome tandem fusion may corroborate the basal condition of M. nemorivaga and its proximity to the ancestral karyotype of the American Odocoileini. A derived karyotype 2n=67, XY1Y2, FN=70 + 3B from the Brazilianstate of Mato Grosso (the western Amazon) may be evidence of differentiation between western and eastern populations. © Bruno Ferreto Fiorillo et al.

Effect of sex and seasons of the year on hematologic and serum biochemical variables of captive brown brocket deer (Mazama gouazoubira)

The Brown brocket deer (Mazama gouazoubira) is the most common free-living and captive deer in South America, especially in Brazil, and has great ecological and scientific significance. However, data on hematological and biochemical parameters in brown brocket deer are scarce. The goal of this study was to establish reference ranges for hematological and biochemical parameters of Mazama gouazoubira, comparing differences during the seasons of the year and between sex. Blood samples from ten adult healthy brown brocket deer (6 female and 4 male) were collected during daytime, monthly, during 12 months. The animals were maintained in individual stable, protected from noise and fed ad libitum with commercial ration and green fodder. For blood collection, animals were submitted to physical restrain for no longer than 2 minutes. The following parameters were determined: red blood cell count (RBC), haemoglobin concentration, packed cell volume (PCV), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), white blood cell count (WBC), platelet count, enzyme activity of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) and serum levels of alkaline phosphatase (ALP), creatine kinase (CK), total protein (TP), albumin, cholesterol, total calcium, ionic calcium, sodium, potassium, magnesium, triglycerides, creatinine and urea. Values were compared according to season and sex. RBC count, WBC count and MCV suggested seasonal influence. Haemoglobin concentration, PCV and MCV were influenced by sex. Serum concentration of total calcium, ionic calcium, sodium, potassium and magnesium were influenced by season. Serum magnesium was also influenced by sex. The blood parameters herein reported may be useful as reference values for diagnostic and prognostic purposes in captive brown-brocket deer.

Filogenia e taxonomia dos veados cinza (Mazama gouazoubira e M. nemorivaga)

Pós-graduação em Genética e Melhoramento Animal - FCAV

Microphallus fonti sp. n. (Digenea: Microphallidae) from the Red Swamp Crawfish in Southern United States

A new species of digenean, Microphallus fonti, is described from the red swamp crawfish in Louisiana, USA. It has a small pharynx and a rudimentary gut like M. opacus and possibly related species from crayfishes, but it differs from them by its relatively large male copulatory papilla and a conspicuous metraterm.

THE EFFECTS OF ORNITROL ON WILD POPULATIONS OF RED-WINGED BLACKBIRDS AND GRACKLES

For the past three years the New Jersey Department of Agriculture, in coop¬eration with the New Jersey Agricultural Experiment Station, has conducted field evaluations on the effects of reproductive suppressants on wild populations of red-winged blackbirds. These studies have been performed in conjunction with the North East 49 (a Federally sponsored regional project which presently has nine states in the North East and Ohio cooperating to develop means to combat bird damage to agricultural crops) regional project on control of bird depredations. Field evaluations in 1968 and 1969 centered around the effects of TEM (tri-ethylene melamine) on the reproductive rates of red-winged blackbirds. At the close of the 1969 season further field testing of the chemical was discontinued because of the material's apparent lack of effectiveness as a reproductive inhibitor. In 1970 the field evaluations were conducted to determine the effects of Orni-trol (20, 25-diazocholesterol dihydrochloride, supplied by G. D. Searle and Company, Chicago, Illinois) on the reproductive rates of red-winged blackbirds. A small colony of common grackles was also studied during this same investigation.

Morphological and molecular studies on the Brazilian native red seaweed Laurencia oliveirana (Rhodomelaceae, Ceramiales)

Morphological and molecular studies were carried out on Laurencia oliveirana from the type locality (Arraial do Cabo, Rio de Janeiro, Brazil). This species is easily recognized by its small size, sub-erect habit forming intricate cushion-like tufts and unilateral pectinate branching. The species displays all the typical characters of the genus Laurencia, such as the production of the first pericentral cell underneath the basal cell of the trichoblast, tetrasporangia produced from particular pericentral cells, with the third and fourth pericentral cells becoming fertile, without production of additional pericentral cells, spermatangial branches produced from one of two laterals on the suprabasal cell of trichoblasts, and procarp-bearing segment with five pericentral cells. Details of tetrasporangial plants and development of procarp and male plants are described for the first time for the species. The phylogenetic position of L. oliveirana was inferred by analysis of the chloroplast-encoded rbcL gene sequences from 57 taxa. In all phylogenetic analyses, L. oliveirana grouped with L. caraibica, L. caduciramulosa, L. venusta and L. natalensis, forming a monophyletic clade within the Laurencia sensu stricto. The genetic divergence between L. oliveirana and the molecularly closest species, L. caraiba collected in Brazil, was 2.3%.

Ecological modelling of the phytoplankton dynamics in the northern Gulf of Aqaba (Red Sea)

The Gulf of Aqaba represents a small scale, easy to access, regional analogue of larger oceanic oligotrophic systems. In this Gulf, the seasonal cycles of stratification and mixing drives the seasonal phytoplankton dynamics. In summer and fall, when nutrient concentrations are very low, Prochlorococcus and Synechococcus are more abundant in the surface water. This two populations are exposed to phosphate limitation. During winter mixing, when nutrient concentrations are high, Chlorophyceae and Cryptophyceae are dominant but scarce or absent during summer. In this study it was tried to develop a simulation model based on historical data to predict the phytoplankton dynamics in the northern Gulf of Aqaba. The purpose is to understand what forces operate, and how, to determine the phytoplankton dynamics in this Gulf. To make the models data sampled in two different sampling station (Fish Farm Station and Station A) were used. The data of chemical, biological and physical factors, are available from 14th January 2007 to 28th December 2009. The Fish Farm Station point was near a Fish Farm that was operational until 17th June 2008, complete closure date of the Fish Farm, about halfway through the total sampling time. The Station A sampling point is about 13 Km away from the Fish Farm Station. To build the model, the MATLAB software was used (version 7.6.0.324 R2008a), in particular a tool named Simulink. The Fish Farm Station models shows that the Fish Farm activity has altered the nutrient concentrations and as a consequence the normal phytoplankton dynamics. Despite the distance between the two sampling stations, there might be an influence from the Fish Farm activities also in the Station A ecosystem. The models about this sampling station shows that the Fish Farm impact appears to be much lower than the impact in the Fish Farm Station, because the phytoplankton dynamics appears to be driven mainly by the seasonal mixing cycle.

Size-selective investigations of spectral and emission properties of small particles and nanotubes

In dieser Arbeit wurde die Elektronenemission von Nanopartikeln auf Oberflächen mittels spektroskopischen Photoelektronenmikroskopie untersucht. Speziell wurden metallische Nanocluster untersucht, als selbstorganisierte Ensembles auf Silizium oder Glassubstraten, sowie ferner ein Metall-Chalcogenid (MoS2) Nanoröhren-Prototyp auf Silizium. Der Hauptteil der Untersuchungen war auf die Wechselwirkung von fs-Laserstrahlung mit den Nanopartikeln konzentriert. Die Energie der Lichtquanten war kleiner als die Austrittsarbeit der untersuchten Proben, so dass Ein-Photonen-Photoemission ausgeschlossen werden konnte. Unsere Untersuchungen zeigten, dass ausgehend von einem kontinuierlichen Metallfilm bis hin zu Clusterfilmen ein anderer Emissionsmechanismus konkurrierend zur Multiphotonen-Photoemission auftritt und für kleine Cluster zu dominieren beginnt. Die Natur dieses neuen Mechanismus` wurde durch verschiedenartige Experimente untersucht. Der Übergang von einem kontinuierlichen zu einem Nanopartikelfilm ist begleitet von einer Zunahme des Emissionsstroms von mehr als eine Größenordnung. Die Photoemissions-Intensität wächst mit abnehmender zeitlicher Breite des Laserpulses, aber diese Abhängigkeit wird weniger steil mit sinkender Partikelgröße. Die experimentellen Resultate wurden durch verschiedene Elektronenemissions-Mechanismen erklärt, z.B. Multiphotonen-Photoemission (nPPE), thermionische Emission und thermisch unterstützte nPPE sowie optische Feldemission. Der erste Mechanismus überwiegt für kontinuierliche Filme und Partikel mit Größen oberhalb von mehreren zehn Nanometern, der zweite und dritte für Filme von Nanopartikeln von einer Größe von wenigen Nanometern. Die mikrospektroskopischen Messungen bestätigten den 2PPE-Emissionsmechanismus von dünnen Silberfilmen bei „blauer“ Laseranregung (hν=375-425nm). Das Einsetzen des Ferminiveaus ist relativ scharf und verschiebt sich um 2hν, wenn die Quantenenergie erhöht wird, wogegen es bei „roter“ Laseranregung (hν=750-850nm) deutlich verbreitert ist. Es zeigte sich, dass mit zunehmender Laserleistung die Ausbeute von niederenergetischen Elektronen schwächer zunimmt als die Ausbeute von höherenergetischen Elektronen nahe der Fermikante in einem Spektrum. Das ist ein klarer Hinweis auf eine Koexistenz verschiedener Emissionsmechanismen in einem Spektrum. Um die Größenabhängigkeit des Emissionsverhaltens theoretisch zu verstehen, wurde ein statistischer Zugang zur Lichtabsorption kleiner Metallpartikel abgeleitet und diskutiert. Die Elektronenemissionseigenschaften bei Laseranregung wurden in zusätzlichen Untersuchungen mit einer anderen Anregungsart verglichen, der Passage eines Tunnelstroms durch einen Metall-Clusterfilm nahe der Perkolationsschwelle. Die elektrischen und Emissionseigenschaften von stromtragenden Silberclusterfilmen, welche in einer schmalen Lücke (5-25 µm Breite) zwischen Silberkontakten auf einem Isolator hergestellt wurden, wurden zum ersten Mal mit einem Emissions-Elektronenmikroskop (EEM) untersucht. Die Elektronenemission beginnt im nicht-Ohmschen Bereich der Leitungsstrom-Spannungskurve des Clusterfilms. Wir untersuchten das Verhalten eines einzigen Emissionszentrums im EEM. Es zeigte sich, dass die Emissionszentren in einem stromleitenden Silberclusterfilm Punktquellen für Elektronen sind, welche hohe Emissions-Stromdichten (mehr als 100 A/cm2) tragen können. Die Breite der Energieverteilung der Elektronen von einem einzelnen Emissionszentrum wurde auf etwa 0.5-0.6 eV abgeschätzt. Als Emissionsmechanismus wird die thermionische Emission von dem „steady-state“ heißen Elektronengas in stromdurchflossenen metallischen Partikeln vorgeschlagen. Größenselektierte, einzelne auf Si-Substraten deponierte MoS2-Nanoröhren wurden mit einer Flugzeit-basierten Zweiphotonen-Photoemissions-Spektromikroskopie untersucht. Die Nanoröhren-Spektren wiesen bei fs-Laser Anregung eine erstaunlich hohe Emissionsintensität auf, deutlich höher als die SiOx Substratoberfläche. Dagegen waren die Röhren unsichtbar bei VUV-Anregung bei hν=21.2 eV. Eine ab-initio-Rechnung für einen MoS2-Slab erklärt die hohe Intensität durch eine hohe Dichte freier intermediärer Zustände beim Zweiphotonen-Übergang bei hν=3.1 eV.

Applications of remote sensing and geographic information systems in geomorphological studies: Safaga - El Quseir area, Red Sea coast, Egypt as an example

In den letzten drei Jahrzehnten sind Fernerkundung und GIS in den Geowissenschaften zunehmend wichtiger geworden, um die konventionellen Methoden von Datensammlung und zur Herstellung von Landkarten zu verbessern. Die vorliegende Arbeit befasst sich mit der Anwendung von Fernerkundung und geographischen Informationssystemen (GIS) für geomorphologische Untersuchungen. Durch die Kombination beider Techniken ist es vor allem möglich geworden, geomorphologische Formen im Überblick und dennoch detailliert zu erfassen. Als Grundlagen werden in dieser Arbeit topographische und geologische Karten, Satellitenbilder und Klimadaten benutzt. Die Arbeit besteht aus 6 Kapiteln. Das erste Kapitel gibt einen allgemeinen Überblick über den Untersuchungsraum. Dieser umfasst folgende morphologische Einheiten, klimatischen Verhältnisse, insbesondere die Ariditätsindizes der Küsten- und Gebirgslandschaft sowie das Siedlungsmuster beschrieben. Kapitel 2 befasst sich mit der regionalen Geologie und Stratigraphie des Untersuchungsraumes. Es wird versucht, die Hauptformationen mit Hilfe von ETM-Satellitenbildern zu identifizieren. Angewandt werden hierzu folgende Methoden: Colour Band Composite, Image Rationing und die sog. überwachte Klassifikation. Kapitel 3 enthält eine Beschreibung der strukturell bedingten Oberflächenformen, um die Wechselwirkung zwischen Tektonik und geomorphologischen Prozessen aufzuklären. Es geht es um die vielfältigen Methoden, zum Beispiel das sog. Image Processing, um die im Gebirgskörper vorhandenen Lineamente einwandfrei zu deuten. Spezielle Filtermethoden werden angewandt, um die wichtigsten Lineamente zu kartieren. Kapitel 4 stellt den Versuch dar, mit Hilfe von aufbereiteten SRTM-Satellitenbildern eine automatisierte Erfassung des Gewässernetzes. Es wird ausführlich diskutiert, inwieweit bei diesen Arbeitsschritten die Qualität kleinmaßstäbiger SRTM-Satellitenbilder mit großmaßstäbigen topographischen Karten vergleichbar ist. Weiterhin werden hydrologische Parameter über eine qualitative und quantitative Analyse des Abflussregimes einzelner Wadis erfasst. Der Ursprung von Entwässerungssystemen wird auf der Basis geomorphologischer und geologischer Befunde interpretiert. Kapitel 5 befasst sich mit der Abschätzung der Gefahr episodischer Wadifluten. Die Wahrscheinlichkeit ihres jährlichen Auftretens bzw. des Auftretens starker Fluten im Abstand mehrerer Jahre wird in einer historischen Betrachtung bis 1921 zurückverfolgt. Die Bedeutung von Regentiefs, die sich über dem Roten Meer entwickeln, und die für eine Abflussbildung in Frage kommen, wird mit Hilfe der IDW-Methode (Inverse Distance Weighted) untersucht. Betrachtet werden außerdem weitere, regenbringende Wetterlagen mit Hilfe von Meteosat Infrarotbildern. Genauer betrachtet wird die Periode 1990-1997, in der kräftige, Wadifluten auslösende Regenfälle auftraten. Flutereignisse und Fluthöhe werden anhand von hydrographischen Daten (Pegelmessungen) ermittelt. Auch die Landnutzung und Siedlungsstruktur im Einzugsgebiet eines Wadis wird berücksichtigt. In Kapitel 6 geht es um die unterschiedlichen Küstenformen auf der Westseite des Roten Meeres zum Beispiel die Erosionsformen, Aufbauformen, untergetauchte Formen. Im abschließenden Teil geht es um die Stratigraphie und zeitliche Zuordnung von submarinen Terrassen auf Korallenriffen sowie den Vergleich mit anderen solcher Terrassen an der ägyptischen Rotmeerküste westlich und östlich der Sinai-Halbinsel.

Protein changes and proteolytic degradation in red and white clover plants subjected to waterlogging

Red (Trifolium pratense L., cv. “Start”) and white clover varieties (Trifolium repens L., cv. “Debut” and cv. “Haifa”) were waterlogged for 14 days and subsequently recovered for the period of 21 days. Physiological and biochemical responses of the clover varieties were distinctive, which suggested different sensitivity toward flooding. The comparative study of morphological and biochemical parameters such as stem length, leaflet area, dry weight, protein content, protein pattern and proteolytic degradation revealed prominent changes under waterlogging conditions. Protease activity in the stressed plants increased significantly, especially in red clover cv. “Start”, which exhibited eightfold higher azocaseinolytic activity compared to the control. Changes in the protein profiles were detected by SDS-PAGE electrophoresis. The specific response of some proteins (Rubisco, Rubisco-binding protein, Rubisco activase, ClpA and ClpP protease subunits) toward the applied stress was assessed by immunoblotting. The results characterized the red clover cultivar “Start” as the most sensitive toward waterlogging, expressing reduced levels of Rubisco large and small subunits, high content of ClpP protease subunits and increased activity of protease isoforms.

Near infra-red-activatable nanocarriers for selective cancer diagnosis and treatment

Standard treatment strategies for cancer patients include surgery, radiation therapy, and chemotherapy. Although these strategies have been proven effective, they also have associated limitations. An attractive and innovative approach that can be used alone or in combination with the above modalities is based on the systemic or topical administration of a nanomaterial-based photoactive compound. Interaction with light in the near infrared (NIR) region results in either emission of fluorescence, which can be used for photodetection, or absorption of light which results in phototherapy. Nanomaterials have the advantage of providing multi-functional and unique properties in a single device that cannot be readily acquired with conventional small molecular weight compounds. ^ In this study, three different novel nanocarrier systems were designed and evaluated in mediating photodetection and phototherapy in the NIR. The first compound synthesized was a dual-labeled magnetic resonance/optical imaging agent for sentinel lymph node mapping and biopsy. This dual-labeled agent combines the high resolution of magnetic resonance imaging with the highly sensitive detection of optical imaging. The second imaging agent was an activatable optical imaging agent used to monitor cathepsin B activity in vivo and to probe the degradation of poly(L-glutamic acid). This polymeric nanocarrier offers highly sensitive technique for the detection of enzymatic activity, with is not yet possible with small molecular weight compounds. The third agent was a C225-conjugated hollow nanoshell that is targeted to epidermal growth factor receptors. This targeting agent has been demonstrated to mediate photothermal therapy both in vitro and in vivo. ^ These nanocarrier systems are an invaluable tool for the detection of cancer and many other diseases. With improved targeted delivery of these agents, the ability to diagnose diseases will become more sensitive and more specific. Finally, when designed properly, these agents would allow concurrent diagnosis and treatment of patients of various diseases. ^