Primary Synovial Sarcoma arising from gingivo-buccal sulcus harbouring SS18-SSX2 positive fusion transcript: The 1st reported case in English literature.

Synovial sarcoma (SS) is a mesenchymal tumour of uncertain histiogenesis that can show dual epithelial and mesenchymal differentiation. Thought to arise predominantly in deep soft tissue of extremities, these sarcomas have shown that they can affect a wide variety of organs and sites, however intraoral mucosal SS is rarely encountered and herein the authors present possibly the second reported case of a young lady presenting with a slow growing tumour arising in the gingivo-buccal sulcus that was reported as Synovial sarcoma on biopsy and subsequently confirmed using molecular studies, tumour demonstrating SS18-SSX2 fusion transcript. Review of the published literature revealed no documented case with molecular fusion transcript making this case the first reported case. This case also highlights the imperative role of immunohistochemistry in tandem with molecular studies to confirm the diagnosis of spindle cell tumours of oral cavity, since squamous cell carcinoma, by far remains the commonest malignancy arising in mucosa lined oral cavity.

Cell cycle control of a holdfast attachment gene in Caulobacter crescentus.

Attachment to surfaces by the prosthecate bacterium Caulobacter crescentus is mediated by an adhesive organelle, the holdfast, found at the tip of the stalk. Indirect evidence suggested that the holdfast first appears at the swarmer pole of the predivisional cell. We used fluorescently labeled lectin and transmission electron microscopy to detect the holdfast in different cell types. While the holdfast was readily detectable in stalked cells and at the stalked poles of predivisional cells, we were unable to detect the holdfast in swarmer cells or at the flagellated poles of predivisional cells. This suggests that exposure of the holdfast to the outside of the cell occurs during the differentiation of swarmer to stalked cells. To investigate the timing of holdfast synthesis and exposure to the outside of the cell, we have examined the regulation of a holdfast attachment gene, hfaA. The hfaA gene is part of a cluster of four genes (hfaABDC), identified in strain CB2A and involved in attachment of the holdfast to the polar region of the cell. We have identified the hfaA gene in the synchronizable C. crescentus strain CB15. The sequence of the CB2A hfaA promoter suggested that it was regulated by sigma54. We show that the transcription of hfaA from either strain is not dependent on sigma54. Using a hfaA-lacZ fusion, we show that the transcription of hfaA is temporally regulated during the cell cycle, with maximal expression in late-predivisional cells. This increase in expression is largely due to the preferential transcription of hfaA in the swarmer pole of the predivisional cell.

Transcriptional and mutational analyses of the rpoN operon in Caulobacter crescentus.

The alternative sigma factor sigma54 is required for the biogenesis of both the flagellum and the stalk in Caulobacter crescentus. The DNA sequence downstream of the sigma54 gene (rpoN) has been determined, revealing three open reading frames (ORFs) encoding peptides of 203, 208, and 159 amino acids. ORF208 and ORF159 are homologous to ORFs found downstream of rpoN in other microorganisms. The organization of this region in C. crescentus is similar to that in other bacteria, with the exception of an additional ORF, ORF203, immediately downstream from rpoN. There is a single temporally regulated promoter that drives the expression of both rpoN and ORF203. Promoter probe analysis indicates the presence of another promoter downstream from ORF203 which exhibits a temporal control that is different from that of the rpoN promoter. Mutational analysis was used to address the function of the proteins encoded by these three downstream ORFs. The mutations have no effect on the transcription of previously known sigma54-dependent flagellar promoters except for a slight effect of an ORF159 mutation on transcription of fljK.

A general method to calculate dose to spine in opposing anterior posterior treatment setup without CT.

The spinal cord is usually part of the treatment volume in the treatment of the thorax and abdomen areas using antero-posterior (AP) and postero-anterior (PA) ports. Thus it is necessary to know the dose the spinal cord would receive. One needs to locate the spine to calculate the dose at that location. In the absence of CT, a set of orthogonal films is taken at simulation to aid in locating the spine. The relative point dose then is calculated using irregular field point dose calculation mode of the treatment planning system. The data needed for the calculation are the x and y coordinates of the spine in the coronal plane, air gap, and depth in tissue. Correct entry of these is thus important to obtain the dose accurately. Planning systems assume that the spine is close to the beam axis. There could be possible mislocation of the spine when this assumption is not valid. This presentation describes a procedure to obtain the needed numbers for a general location without any assumptions. To obtain x and y coordinates the suggestion is made to solve numerically using successive approximation series for the coordinates, the series continued until mutually consistent values are obtained. The other parameters, g and d, are obtained from the source to skin distance (SSD) above the spine point, with the use of multiple transaxial contours in association with the principle of linear interpolation.(ABSTRACT TRUNCATED AT 250 WORDS)

Temperature dependence of the electron spin-lattice relaxation rate from pulsed EPR of CUA and heme a in cytochrome c oxidase.

This work shows the feasibility of using pulsed, saturation recovery EPR to study directly the magnetic relaxation properties of metal centers in cytochrome c oxidase in the 1.5-20 K range. Heme a and CuA both showed remarkably similar Tn temperature dependences in their spin-lattice relaxation rates. Either both are in environments with very similar protein backbone configurations (Stapleton, H.J., J.P. Allen, C.P. Flynn, D.G. Stinson, and S.R. Kurtz, 1980, Phys. Rev. Lett., 45:1456-1459; Allen, J.P., J.T. Colvin, D.G. Stinson, C.P. Flynn, and H.J. Stapleton, 1982, Biophys. J., 38:299-310), or the CuA is relaxed by nearby heme a. Spin-lattice relaxation of the nitrosylferrocytochrome a3 center in mixed valence oxidase showed enhancement of relaxation by a nearby paramagnetic center, most likely heme a.

Perfluorinated organic liquids and emulsions as biocompatible NMR imaging agents for 19F and dissolved oxygen.

Emulsions of fluorocarbons are finding considerable use in physiology for intravascular oxygen transport. Their wide clinical application as blood substitutes, anti-shock, and anti-ischemic agents seems imminent. Whole body NMR imaging is rapidly gaining clinical application and may one day almost completely supplant X-ray imaging. All of the 19F compounds used in biocompatible fluorocarbon emulsions give 19F signals identical to those in the corresponding neat liquid. In concentrations of 10% w/v they are readily imaged. The paramagnetic oxygen molecule reduces T1 in such a way as to make possible whole body imaging of oxygen. T1 typically decreases from 1-4 to 0.3-0.5 seconds and is an inverse linear function of oxygen tension. Spin-lattice relaxation times versus oxygen tensions from 0 to 600 torr have been obtained for F-decalin, F-tributylamine, and F-44E. The usefulness of these 19F effects in clinical NMR imaging depends upon the sensitivity of the method and the tolerable dose. The 19F signal may find use in monitoring 19F compounds as vapors or gases dissolved in plasma or in perfluorocarbons in neat liquid or particle form.

Effects of ozone on meiotic chromosomes of Vicia faba.

All of the levels of ozone used in these experiments caused morphological damage to plants of Vicia faba L., but only the dose of 200 parts per hundred million for 4 h or 8 h caused chromosomal damage in the microsporocytes. Significant chromosomal damage appeared 24 h after fumigation in metaphase I and anaphase I - telophase I but no significant damage was found in anaphase II - telophase II. This observation suggests that chromosomes are more susceptible to ozone during early stages of meiosis than at later stages. Chromosomal damage was of two types: physiological, as suggested by chromosome stickiness and physical, as indicated by bridges, fragments, and micronuclei.