A review of applications of MRI in soft tissue and bone tumors

Due to excellent soft tissue contrast and multiplanar imaging capability, MRI is assuming a major role in recognition, staging, and treatment planning of soft tissue and bone tumors. Direct sagittal, coronal, and axial images permit assessment of intraosseous and extraosseous extension of tumors and their relationship to the joints and neurovascular structures, and detection of "skip" lesions. MRI allows improved detection of recurrent tumors in the presence of non-ferromagnetic metallic implants as compared to CT. In the evaluation of soft tissue tumors, MRI is more sensitive than CT and allows differentiation among fat, muscle, tendon, bone, and vascular structures based on signal characteristics. Over a period of 18 months, 100 soft tissue masses and bone tumors were evaluated using MRI. Spin echo sequences with T1 and T2 weighted images were most valuable in differentiating normal and abnormal tissues. Calculated comparative measurements of relaxation times showed no reliable difference between benign and malignant tumors.     

Neoglycoprotein binding to colorectal tumour cells: Comparison between primary and secondary lesions

Summary Biotinylated neoglycoproteins are useful to determine the expression of sugar receptors (lectins) histochemically in routinely processed tissue sections. Assessment of the presence of distinct receptor classes with specificity to-galactosides and to- or-N-acetylgalactosamine, selected on the basis of their potential relevance for recognition processes within the metastatic cascade in murine model systems, was performed for a common human tumour type, colorectal cancer. The four different types of neoglycoproteins, derived from covalent attachment of commercially available derivatives of-N-acetylgalactosamine, differed only quantitatively in their capacity to detect specific binding on cultured cells and tissue sections, thus posing no major restriction on the choice of synthetic process for histochemical efficiency of the product. Glycocytological application revealed specific probe binding and a regulation of level of receptor expression for a human colon carcinoma cell line primarily forN-acetylgalactosamine-specific receptors upon retinoic acid-induced differentiation. Monitoring of sections of the 12 cases of primary and secondary colorectal lesions invariably disclosed the presence of the respective receptors, the extent of cell labelling in primary tumours and metastases being similar. Establishment of metastases, even in different target organs, is apparently not followed by a major phenotypic variation in this feature.     

Alteration of the LRP1B gene region is associated with high grade of urothelial cancer

We have delineated regions of interest at chromosome 2q21.2, 2q36.3, and 2q37.1 by deletion mapping of 114 urothelial cancers (UC). Altogether, 17%, 18%, and 63% of the G1, G2, and G3 tumors displayed loss of heterozygosity at chromosome 2q, respectively, The region at 2q21.2 was narrowed down to the LRP1B gene (NT_005129.6). Hemi- and homozygous deletion at the LRP1B gene region was seen in 31 of 114 UCs. Only 8% of the UCs with G1 and none with G2 tumors showed loss of heterozygosity at the LRP1B gene, whereas 49% of the G3 UCs had allelic loss at this region. RT-PCR analysis of the LRP1B gene showed the lack of expression of several exons in 2 of 9 cases analyzed. Our analysis suggests that the LRP1B gene is a candidate tumor suppressor gene in UCs.     

The stability of methacrylate biomaterials when enzyme challenged: kinetic and systematic evaluations

This study addressed whether methacrylate monomers and polymers used in dentistry might degrade from enzymolysis by acetylcholinesterase (ACHE), cholesterol esterase (CHE), porcine liver esterase (PRLE), and a pancreatic lipase (PNL). Short (hour) and long-term (day) exposures were performed. Product ratios were used to determine surface hydrolysis of the polymeric materials. Enzyme kinetics were studied for the monomers when challenged by ACHE, CHE, and PRLE. In the case of PRLE, the V(max) for the dimethacrylate substrates varied slightly, but amounted to as much as 10% of that of p-nitrophenylacetate. The K(m) for triethylene glycol dimethacrylate (TEGDMA) was 197 microM for ACHE and 1107 microM for CHE. The V(max) was 2.7 nmol/min for ACHE and 3.5 nmol/min for CHE. TEGDMA was converted by CHE at 2% the rate of cholesteryl oleate. Long-term incubations of monomers with CHE and ACHE produced degrees of hydrolysis that evidenced structure dependency in the ability of the enzymes to effect hydrolysis. Particularly resistant were aromativ derivatives and those with branching in methacrylate linkages. Overall, the study confirms the ability of physiologically important esterases to catalyze the hydrolysis of biomaterial methacrylates.     

Pathogen and resistance spectrum in intraoral infections of the jaw-facial area with special reference to anaerobic bacteria]

The aim of the study was to obtain more knowledge about the aerobic and anaerobic species causing maxillofacial infections and their resistance patterns today. Samples of pus or infectious tissue obtained from 110 patients of maxillofacial surgery were investigated microbiologically by means of aerobic and anaerobic cultivation. After incubation, the cultivated species were isolated and identified. The resistance patterns of all bacteria to penicillin, doxycyclin, and clindamycin were determined. Additionally, the resistance of aerobic species to cefuroxim was documented, and the MICs of cefoxitin and metronidazole to the anaerobic species were assessed. The most frequent disease was periodontitis apicalis (70 patients). Aerobic species alone were found in 23% of the samples, 14% of the infections harbored only anaerobes, but 63% were mixed infections caused by aerobic and anaerobic bacteria. In case of detection of aerobic species, streptococci were always identified. Five patients were infected by Staphylococcus aureus and gram-negative aerobic rods were found in eight patients. Most of the anaerobic species were black pigmented prevotella species (62), nonpigmented prevotellae (56), and fusobacteria (37). Metronidazole and clindamycin were highly efficient to gram-negative anaerobic rods. Most of the oral species were resistant to penicillin and doxycyclin. The indication for applying antibiotics should always be noticed and these drugs should only be used after determination of the pathogenic microorganisms and their susceptibility to the antimicrobials.     

A systematic review on the Rosa canina effect and efficacy profiles

Rose hip, rose hip and seed and rose hip seed, all were negatively monographed by the German Commission E due to insufficient evidence of effects and effectiveness. Therefore a comprehensive review of the literature was conducted to summarize the pharmacological and clinical effects of Rosa canina L. to reevaluate its usefulness in traditional medicine. For various preparations of rose hip and rose hip and seed, antioxidative and antiinflammatory effects have been demonstrated. Lipophilic constituents are involved in those mechanisms of action. The proprietary rose hip and seed powder Litozin has been employed successfully in a number of exploratory studies in patients suffering from osteoarthritis, rheumatoid arthritis and low back pain. However, the sizes of the clinical effects for the different indications need to be determined to assure clinical significance. There is also a rationale behind the use of Litozin as part of a hypocaloric diet based on the rose hip probiotic, stool regulating and smooth muscle-relaxing actions, as well as the rose hip seed lipid-lowering, antiobese and antiulcerogenic effects. Further research is needed to clarify the importance of the reported promising experimental effects in clinical use and to characterize the optimum rose hip seed oil preparation for topical use in the treatment of skin diseases.