An SPR investigation into the therapeutic drug monitoring of the anticancer drug imatinib with selective aptamers operating in human plasma.

The anticancer drug imatinib is often involved in therapeutic drug monitoring (TDM) studies aimed at improving the treatment of several forms of leukemia and gastrointestinal stromal tumors (GIST). To further implement the TDM of imatinib in clinical practice, we developed a detection assay by using an ssDNA aptamer, which demonstrated excellent selectivity and was not affected by interference from the components of human plasma samples. The efficient binding of imatinib to the aptamer was demonstrated by means of surface plasmon resonance (SPR) analysis, which allowed the development of a quantitative assay in the concentration range between 400 and 6000 ng mL (0.

ELISA assay employing epitope-specific monoclonal antibodies to quantify circulating HER2 with potential application in monitoring cancer patients undergoing therapy with trastuzumab.

Circulating HER2 extracellular domain (HER2 ECD) levels were proposed as a surrogate for HER2 tissue expression to monitor breast cancer patients for early relapse or responses to standard or HER2-targeted therapies, such as the monoclonal antibody (mAb) trastuzumab. Currently, available commercial ELISA assays for HER2 ECD rely on antibodies recognizing undisclosed or unknown epitopes. In this work, two ELISA assays employing MGR2 and MGR3 epitope-specific mAbs for HER2 ECD were developed and validated, showing good assay precision and linearity of the dose-response signal within the dynamic range of 0.

Practical fluorimetric assay for the detection of anticancer drug SN-38 in human plasma.

The implementation of therapeutic drug monitoring in the routine clinical practice in oncology is mainly limited by the lack of therapeutic indexes for the majority of the anticancer drugs, and by the absence of suitable analytical tools, which can accurately quantify in real time the concentration of the administered drugs and their relevant metabolites in biological fluids. In this work, a simple and efficient fluorimetric determination of SN-38, the active metabolite of the anticancer drug irinotecan, was developed and applied to human plasma samples. The intrinsic fluorescence of SN-38 allowed its quantification in the range 10-500 ng mL with a LOQ of 5.

Ultra-small dye-doped silica nanoparticles via modified sol-gel technique.

In modern biosensing and imaging, fluorescence-based methods constitute the most diffused approach to achieve optimal detection of analytes, both in solution and on the single-particle level. Despite the huge progresses made in recent decades in the development of plasmonic biosensors and label-free sensing techniques, fluorescent molecules remain the most commonly used contrast agents to date for commercial imaging and detection methods. However, they exhibit low stability, can be difficult to functionalise, and often result in a low signal-to-noise ratio.

Enzyme-Based Electrochemical Biosensor for Therapeutic Drug Monitoring of Anticancer Drug Irinotecan.

Therapeutic drug monitoring (TDM) is the clinical practice of measuring pharmaceutical drug concentrations in patients' biofluids at designated intervals, thus allowing a close and timely control of their dosage. To date, TDM in oncology can only be performed by trained personnel in centralized laboratories and core facilities employing conventional analytical techniques (e.g.

Biosensing Technologies for Therapeutic Drug Monitoring.

Background And Rationale: Therapeutic drug monitoring (TDM) is the clinical practice of measuring pharmaceutical drug concentrations in patients' biofluids at designated intervals to allow a close and timely control of their dosage. This practice allows for rapid medical intervention in case of toxicity-related issues and/or adjustment of dosage to better fit the therapeutic demand. Currently, TDM is performed in centralized laboratories employing instruments, such as immunoassay analyzers and mass spectrometers that can be run only by trained personnel.

Human NDE1 splicing and mammalian brain development.

Exploring genetic and molecular differences between humans and other close species may be the key to explain the uniqueness of our brain and the selective pressures under which it evolves. Recent discoveries unveiled the involvement of Nuclear distribution factor E-homolog 1 (NDE1) in human cerebral cortical neurogenesis and suggested a role in brain evolution; however the evolutionary changes involved have not been investigated. NDE1 has a different gene structure in human and mouse resulting in the production of diverse splicing isoforms.

Label-free efficient and accurate detection of cystic fibrosis causing mutations using an azimuthally rotated GC-SPR platform.

Plasmonic nanosensors are candidates for the development of new sensors with low detection limits, high sensitivity, and specificity for target detection: these characteristics are of critical importance in the screening of mutations responsible for inherited diseases. In this work, we focused our study on the detection of some of the most frequent mutations responsible for cystic fibrosis (CF) among the Italian population. For the detection of the CF mutations we adopted a recently developed and highly sensitive Grating Coupled-Surface Plasmon Resonance (GC-SPR) enhanced spectroscopy method for label-free molecular identification exploiting a conical illumination configuration.

Sensitive detection of Ochratoxin A in food and drinks using metal-enhanced fluorescence.

Easy, sensitive, rapid and low cost ochratoxin biosensors are strongly demanded in food analysis since Ochratoxin A (OTA) is a widely diffused food contaminant, highly detrimental for human health. In this work, a novel plasmonic based optical biosensor prototype for ochratoxin A is described. It exploits the metal-enhanced fluorescence phenomenon due to the silver film over nanosphere plasmonic substrate.

Development of a multiplex sandwich aptamer microarray for the detection of VEGF165 and thrombin.

In this work we have developed a multiplex microarray system capable of detecting VEGF165 and thrombin. We recently described a Sandwich Aptamer Microarray (SAM) for thrombin detection feasible for use in multiplex microarrays; here we describe a new aptasensor for VEGF165 detection employing Vap7 and VEa5, two DNA aptamers recognizing different sites of the protein. The aptamers were modified to be adapted to the solid phase platform of SAM and their capability to simultaneously recognize VEGF165 by forming a ternary complex was analyzed in solution.

Development and Optimization of a Thrombin Sandwich Aptamer Microarray.

A sandwich microarray employing two distinct aptamers for human thrombin has been optimized for the detection of subnanomolar concentrations of the protein. The aptamer microarray demonstrates high specificity for thrombin, proving that a two-site binding assay with the TBA1 aptamer as capture layer and the TBA2 aptamer as detection layer can ensure great specificity at times and conditions compatible with standard routine analysis of biological samples. Aptamer microarray sensitivity was evaluated directly by fluorescent analysis employing Cy5-labeled TBA2 and indirectly by the use of TBA2-biotin followed by detection with fluorescent streptavidin.

Human thrombin detection through a sandwich aptamer microarray: interaction analysis in solution and in solid phase.

We have developed an aptamer-based microarray for human thrombin detection exploiting two non-overlapping DNA thrombin aptamers recognizing different exosites of the target protein. The 15-mer aptamer (TBA1) binds the fibrinogen-binding site, whereas the 29-mer aptamer (TBA2) binds the heparin binding domain. Extensive analysis on the complex formation between human thrombin and modified aptamers was performed by Electrophoresis Mobility Shift Assay (EMSA), in order to verify in solution whether the chemical modifications introduced would affect aptamers/protein recognition.

Signal enhancement in DNA microarray using dye doped silica nanoparticles: application to human papilloma virus (HPV) detection.

DNA microarray is a powerful tool for the parallel of nucleic acids and other biologically significant molecules. In this communication we report an easy and cheap synthesis route for incorporating organic dyes into monodisperse inorganic silica nanoparticles and their application on the detection of carcinogenic risky Human Papilloma Virus using DNA microarray technology. We correlate our system with conventional direct dyes and commercial quantum dots, with a promising increase in optical signal, and a related decrease of the limit of detection, thus giving a remarkable improvement in this technique towards early diagnosis of diseases and trace level detection of dangerous biological contaminants.

[Chronic spondylodiscitis. Clinical aspects and imaging features].

Introduction: The diagnosis of a chronic inflammatory process involving the vertebral body and disk is often very difficult because patient's history, subjective symptoms and physical findings are often unconclusive. Thus imaging techniques play a decisive role. Radiography, tomography, CT and MR have different capabilities and limitations and provide different findings in spondylodiscitis.

[Destructive arthrosis of the hip. Natural history, pathogenesis, and radiographic features].

Degenerative hip arthritis is caused by the joint failing to bear the normal walk load, because of changes in the anatomical components and of some factors leading to static or dynamic unbalance of the joint surfaces. Degenerative arthritis usually evolves slowly, but its evolution is rapid under certain circumstances and in elderly patients. In such cases destruction is severe and irregular erosions are observed in the femoral heads, which become small and move to the superior lateral edge of the acetabulum.

[Neurogenic senile vertebral spondylopathy].

Neurogenic spinal arthropathy is quite frequent a finding in elderly patients. Peripheral neuropathy underlies this complication. As a matter of fact, impaired proprioception and sensitivity, which are often associated with lesions of the motor nerves, prevent the joint or bone segment submitted to repeated traumas from perceiving alarm sensations, especially pain.

[Aseptic osteonecrosis of the femoral head in cancer patients with neuropathies caused by vincristine and vinblastine].

Aseptic osteonecrosis has been described in many and dissimilar pathologic conditions--most frequently as the aftermath of fractures or dislocations; in falciform anemia, obesity, alcoholism; in diseases requiring constant and heavy corticosteroid therapy, and also following renal transplantation. Many of these pathologies, especially alcoholism, diabetes, uremia, and collagen vascular diseases, have a common denominator: peripheral neuropathy, which is believed to be a pathogenetic factor supporting osteonecrosis. The authors analyze 3 cases of aseptic osteonecrosis of the femoral head in cancer patients treated with vincristine and/or vinblastine.

Perforations of the extraperitoneal rectum during barium enema.

Rectal injuries during barium enema are uncommon but not unusual complications. Radiologists and surgeons must be able to recognize them, as early diagnosis is essential for effective treatment. The Authors discuss various aspects of problems arising from rectal perforation, and report their experience on seven cases.

Osteonecrosis of the femoral head after renal transplantation. Pathogenetic considerations.

In 5 out of 16 renal transplantation patients, osteonecrosis of the femoral head developed in the presence (p less than 0.01) of significant uremic neuropathy; its possible pathogenetic role is discussed.

[Thickening of the bronchial wall in asthma and asthma-like bronchitis].

Small ring-shaped images, related to 2nd or 3rd bronchial walls are seen in prahilar lung region in 80% of chest Xray films, when a bronchus in seen "end on". This bronchial wall thickening (greater than 0.3 mm) is present in numerous lung diseases such as silicosis, bronchiectasis and pulmonary edema.

Lesions of the spine in heroin addicts.

The authors present 6 cases of spinal lesions in heroin addicts--3 infective, 3 traumatic. The striking feature about all these cases is the comparative absence of spinal symptoms. This underlines the importance of accurate and early diagnosis in these subjects.

Neuropathic arthropathy (Charcot's joint) in dialysis patients.

To the author's knowledge, uraemic neuropathy has not been previously reported as a cause of Charcot's joint. In this paper they present three cases in which the association between clinical and radiographic patterns suggest the diagnosis of neuropathic arthropathy. The features of uraemic neuropathy are stressed and the role of secondary hyperparathyroidism in the development of this type of arthropathy is discussed.