Adenovirus type-5 entry and disassembly followed in living cells by FRET, fluorescence anisotropy, and FLIM.

We have used fluorescence resonance energy transfer (FRET) to follow the process of capsid disassembly for adenovirus (Ad) serotype 5 (Ad5) in living CHO-CAR cells. Ad5 were weakly labeled on their capsid proteins with FRET donor and acceptor fluorophores. A progressive decrease in FRET efficiency recorded during Ad5 uptake revealed that the time course of Ad5 capsid disassembly has two sequential protein dissociation rates with half-times of 3 and 60 min.

Interaction of metastasis-inducing S100A4 protein in vivo by fluorescence lifetime imaging microscopy.

Elevated levels of the calcium-binding regulatory protein, S100A4, have been shown to be causative of a metastatic phenotype in models of cancer metastasis and to be associated with reduced patient survival in breast cancer patients. Recombinant S100A4 protein interacts in vitro in a calcium-dependent manner with the heavy chain of non-muscle myosin isoform A at a protein kinase C phosphorylation site. At present, the mechanism of metastasis induction by S100A4 in vivo is almost completely unknown.

Heterodimeric interaction and interfaces of S100A1 and S100P.

With the widespread use of yeast two-hybrid systems, many heterodimeric forms of S100 proteins have been found, although their biological significance is unknown. In the present study, S100A1 was found to interact with another S100 protein, S100P, by using the yeast two-hybrid system. The binding parameters of the interaction were obtained using an optical biosensor and show that S100P has a slightly higher affinity for S100A1 (K(d)=10-20 nM) when compared with that for self-association (K(d)=40-120 nM).

Comments on: A methodology for evaluation of boundary detection algorithms on medical images.

In this paper we analyze a result previously published about a comparison between two statistical tests used for evaluation of boundary detection algorithms on medical images. We conclude that the statement made by Chalana and Kim (1997) about the performance of the percentage test has a weak theoretical foundation, and according to our results, is not correct. In addition, we propose a one-sided hypothesis test for which the acceptance region can be determined in advance, as opposed to the two-sided confidence intervals proposed in the original paper, which change according to the estimated quantity.

A computational TW3 classifier for skeletal maturity assessment. A Computing with Words approach.

This paper proposes a fuzzy methodology to translate the natural language descriptions of the TW3 method for bone age assessment into an automatic classifier. The classifier is built upon a modified version of a fuzzy ID3 decision tree. No large data records are needed to train the classifier, i.

Delayed myocardial perforation following pacemaker implantation.

Myocardial perforation is a rare complication following pacemaker implantation that may cause cardiac tamponade. If it does occur, it is usually at the time of lead insertion. This condition requires urgent recognition since the prompt drainage of the pericardial fluid may be lifesaving.

A theoretical framework to three-dimensional ultrasound reconstruction from irregularly sampled data.

Several techniques have been described in the literature in recent years for the reconstruction of a regular volume out of a series of ultrasound (US) slices with arbitrary orientations, typically scanned by means of US freehand systems. However, a systematic approach to such a problem is still missing. This paper focuses on proposing a theoretical framework for the 3-D US volume reconstruction problem.

Preformed oligomeric epidermal growth factor receptors undergo an ectodomain structure change during signaling.

Fluorescence resonance energy transfer (FRET) was used to reveal aspects of the mechanism of signal transduction by epidermal growth factor receptors (EGFR). The superpositions of epidermal growth factor (EGF), transforming growth factor-alpha (TGFalpha) and an antibody fragment (29.1) to the carbohydrate extremity of the receptor's ectodomain as measured by FRET, show that 14% of EGFRs in A431 cells are oligomerized before growth factor binding.

Real-time studies of the interactions between epidermal growth factor and its receptor during endocytic trafficking.

The interactions of growth factors with cell surface receptors regulate fundamental cell processes, such as growth, differentiation and transformation. Understanding the nature of these interactions at the molecular level is of fundamental importance in cell biology. This is not only from the point of view of basic science, but also because of the repercussions such knowledge might have in understanding the mode of action of drugs in cells.

[Renal cell carcinoma. Clinical onset with peritoneal carcinomatosis. Report of a case].

Renal carcinoma accounts for 2-3% of malignant tumours in the adult, with high tendency for metastasis basically in liver, lymph nodes, lungs and bones. Intraperitoneal, gut, mesentery and omentum involvement is extremely rare affecting only 1% of patients with metastasis at post-mortem. Contribution of one case of renal carcinoma with initial presentation as intraperitoneal metastasis.

Time-resolved X-ray diffraction studies of myosin head movements in live frog sartorius muscle during isometric and isotonic contractions.

Using the facilities at the Daresbury Synchrotron Radiation Source, meridional diffraction patterns of muscles at ca 8 degrees C were recorded with a time resolution of 2 or 4 ms. In isometric contractions tetanic peak tension (P0) is reached in ca 400 ms. Under such conditions, following stimulation from rest, the timing of changes in the major reflections (the 38.

Two-dimensional time-resolved X-ray diffraction studies of live isometrically contracting frog sartorius muscle.

Results were obtained from contracting frog muscles by collecting high quality time-resolved, two-dimensional, X-ray diffraction patterns at the British Synchrotron Radiation Source (SERC, Daresbury, Laboratory). The structural transitions associated with isometric tension generation were recorded under conditions in which the three-dimensional order characteristic of the rest state is either present or absent. In both cases, new layer lines appear during tension generation, subsequent to changes from activation events in the thin filaments.

A comparative study of the supramolecular structure of frog sartorius and dorsal semitendinosus muscle.

This report describes a comparative X-ray diffraction study of the supramolecular structure of frog sartorius and semitendinosus muscles. For sarcomere lengths of 2.7 microns and below the X-ray diffraction diagrams of each muscle type are very similar; the only differences being that the diffraction diagram for semitendinosus muscles exhibit the presence of a broad diffraction band or a cluster of diffraction orders at a spacing of ca.

Two-dimensional time resolved X-ray diffraction of muscle: recent results.

This report provides a preliminary sketch of the results obtained in a two-dimensional time resolved X-ray diffraction study of "live" frog sartorius muscles undergoing isometric tetani. These results demonstrate the recently developed capability to record time resolved (10 msec time resolution), two-dimensional X-ray diffraction diagrams throughout the cycle of contraction. The correlation between the time courses of the diffraction features in the whole of the diffraction diagram establishes a sequence of structural events, which suggest that during the transition from rest to the plateau of tension and the subsequent recovery, the following sequence of events takes place: a) Following the activation phase, which is best monitored by the increase of intensity on the second actin layer line at 18.

Properties and function of malate enzyme from Pseudomonas putida.

Malate enzyme (L-malate: NADP+ oxidoreductase (oxalacetate-decarboxylating, EC 1.1.1.