Search

Immediate intraoperative control via suitable imaging techniques is necessary to achieve the best possible surgical outcome. Intraoperative imaging increases patient safety, offers the surgeon direct support in challenging anatomic regions, and affords the possibility of direct correction with a reduced rate of corrective surgery. The procedures are based on cone beam computed tomography (CBCT), endoscopy, or navigation-assisted surgery. This article describes available intraoperative quality management modalities for fracture management and tumor treatment in the field of head and neck surgery.

Plasma cell myelomas (PMs) have a poor prognosis. Cancer-testis (CT) antigens are immunogenic proteins, representing potential targets for tumor vaccination strategies. The expression of the CT antigens GAGE, MAGE-A4, MAGE-C1/CT-7, and NY-ESO-1 was investigated on paraffin-embedded bone marrow biopsies from 219 PM and 8 monoclonal gammopathy of undetermined significance (MGUS) patients. The frequency and prognostic impact of these CT antigens were compared with known morphological prognostic markers (i.e. Mib1 labeling index) and the presence of the translocations t(4;14)(p16.3; q32) and t(11;14)(q13;q32). We show that MAGE-C1/CT-7 is the most prevalent CT antigen, expressed in 57% of PMs in a high percentage of tumor cells. While MAGE-C1/CT-7 was absent in non-malignant plasma cells, plasma cells of patients with MGUS did express MAGE-C1/CT-7, but no other CT antigens. MAGE-C1/CT-7 was more frequently expressed in PMs with an elevated proliferation rate (Mib1 >10%) compared to PMs with a low proliferation rate (Mib1

Organic monolayers of 1,2-dipalmitoyl-sn-glycero-3-phosphothioethanol or dipalmitoyl-phosphatityl-choline, transferred by the Langmuir−Blodgett technique in phase-coexistence regions onto a solid support, show domains differing in their molecular packing. Domains with dense molecular packing and quite upright orientation of the molecules are neighbored by a matrix with lower packing density and variable molecular orientation. In the scanning force microscope, these domains can be distinguished by a small difference in their layer heights. In the field emission scanning electron microscope (FESEM), these small height differences were not detectable. Coated monolayers show no topographic features of different domains in secondary electron (SE) micrographs. In opposition to that, the domains are easily recognizable in SE micrographs of the uncoated monolayer by a very strong contrast which presents almost a black/white pattern. Thus, the FESEM may serve as a sensitive tool for mapping areas of different mole...

In two experimental studies we sought preliminary information about the behavior of concrements lost in the peritoneal cavity during laparoscopic cholecystectomy.In study 1, human gallstones were analyzed using X-ray diffraction, classified in three groups and examined with an ultramicroscope; then they were implanted in the peritoneal cavity of rats. After 8 weeks or 6 months, the animals were sacrificed and the concrements analyzed again as before. The tissues surrounding the calculi were also examined histologically. In study 2, human gallstones were examined with regard to bacterial contamination on the surface or in the middle of the calculi. The cholesterol content was analyzed, and the stones were divided into three groups and implantated in the rats as in the first study. After 8 weeks, the animals were sacrificed and areas with identifiable tissue reactions were examined histologically and microbiologically.The concrements lost their crystalline formation without any relation to their former cholesterol content, as shown by X-ray diffraction as well as ultramicroscopy. Mineralogically, these changes are a certain sign of structural dissolution. Cholesterol stones only caused abscess formations in association with gram-negative bowel germs. Sterile pigment concrements often led to a mesenchymal reaction such as granulomas. Contaminated pigment stones also resulted in extensive abscess formations.

PPROM occurs in approximately 1% of all pregnancies and 30–40% of preterm deliveries. No satisfactory treatment of PPROM is currently available. Here we studied the human amnion epithelial and mesenchymal cells cultured in three-dimensional (3D) collagen I and fibrin matrices with the objective to develop an implant for application in PPROM. To mimic the architecture of native amnion, amnion mesenchymal cells were embedded in 3D matrices and epithelial cells were placed on top of these matrices. Cell viability, morphology and proteolytic activity of matrix metalloproteinases(MMPs) were investigated. Epithelial and mesenchymal cells in modified 3D fibrin cell-matrix systems remained vital and acquired their natural morphologies. In addition, in fibrin matrices supplemented with fibronectin, mesenchymal cells activated proteolytic programs of tissue repair, demonstrated by the activation of MMP-9. We also studied the growth of amnion cells in collagen I matrix. One limitation of this approach is contraction of collagen I matrices. In vivo, such a size reduction would result in failure of the implant followed by clinical consequences. In contrast to the collagen I matrix, no decrease in the size of fibrin cell-matrices was observed. To conclude 3D fibrin matrices supplied with amnion cells might be useful in treatment of PPROM.

Among the variety of parameters affecting immuno-gold labelling efficiency, mainly the effects of different preparative protocols were tested. Preservation of ultrastructure and of antigenicity are the salient features of this study. We have labelled insoluble components of the secretory matrix of Paramecium trichocysts with specific antisera, using 10 nm colloidal gold particles. The highest labelling efficiency was obtained with fast freezing (cryofixation, either by sandwich or spray-freezing), freeze-substitution in methanol (without added fixatives) and hydrophilic Lowicryls, particularly when applied at low temperatures (K11M at 193 K). The presence of different chemical fixatives always reduced the labelling density and some recommendations from the literature do not appear advisable. Methods commencing with fixation at greater than or equal to 0 degree C, such as "progressive lowering of temperature" (PLT) or preparation of cryostat sections, i.e. with chemical pretreatments, always resulted in lower labelling density. Our data appear, therefore, relevant for optimal immuno-gold labelling of insoluble antigens and emphasize the potential of cryofixation as a primary preparation step. In addition, ultrastructural preservation was also superior after cryofixation.

Important parameters for the detection of small colloidal immunogold particles (10 nm) on cell surfaces include the use of field emission SEM (FESEM) and a need for a conductive metal coating to reduce charging, so as to facilitate backscatter electron (BSE) imaging for unambiguous identification by atomic number contrast. Recently Heinzmann et al (1) have reported the use of below-lens FESEM for detection of 10 nm colloidal gold at working distances of 6-13 mm, but achieved success only on uncoated cells as coating with a 1 nm layer of platinum appeared to mask the gold signal. To improve specimen conductivity and signal collection, three metals (Cr, Pt, W) have been used to generate thin coatings either by planar magnetron sputtering for cryoSEM or ion-beam sputtering for routine chemically-fixed, critical point dried samples (2,3)Three below-lens FESEM (Hitachi S-4500, JEOL 630land 63401, and LEO 982) were tested by using a sample of human neutrophils which had been chemically fixed, then immunostained for the surface antigen CD43 with 10 nm colloidal gold, and prepared by critical point drying.