Magnetic resonance tomography in the diagnosis of juvenile nasopharyngeal angiofibromas

This work is based upon the experience in the diagnosis of juvenile nasopharyngeal angiofibromas (JAF) in 14 patients using MR-tomography and routine x-ray examination. In all the patients MR-tomography made it possible to assess the topical position of a tumor, its spreading to the cranial, nasal, accessory sinusal and orbital cavities, and the pterygopalatine and infratemporal spaces. MR-tomographic diagnosis made it possible to differentiate between tumor invasion and inflammatory processes detecting JAF attending tubotitides. However MR-tomography cannot be used alone to assess the status of osseous tissue.     

Prominent collagen type VI expression in juvenile angiofibromas

The extracellular matrix component collagen type VI demonstrates potent growth-stimulatory effects and has been associated with aggressive tumour growth. Although, juvenile angiofibromas (JAs) often exhibit an aggressive growth pattern, the collagen type VI expression of this fibrovascular tumour has not been addressed so far. RT-PCR, Western blot analysis and immunohistochemistry were used in this study to analyse collagen type VI, type VI collagen receptor subunits (integrin α1, α2, α10, α11 and β1) and the type VI collagen receptor NG2 in JAs (N = 15) and nasal mucosa (NM, N = 8) samples. The mRNA expression of all three collagen type VI chains was found to be up-regulated significantly (P < 10⁻³–10⁻⁵, adjusted) in JAs compared to NM tissues. The Western blot analysis proved highly prominent collagen-type VI expression in JAs. The ApoTome technique revealed strong collagen-type VI signals in tumour endothelium. NG2 (P < 10⁻³, adjusted) and α11-integrin (P = 0.04, adjusted) showed a significantly higher mRNA expression levels in JAs than in NM samples. NG2, α1-, α2- and β1-intergin were located to tumour vessels, and additional stromal signals were observed for NG2 and α1-integrin in JAs. This study demonstrates a prominent collagen-type VI expression in JAs. The collagen-type VI may exert an important growth stimulus in this tumour.     

Hemobilia--evolution of current diagnosis and treatment.

"Hemobilia," upper gastrointestinal tract bleeding that originates from within the biliary tract, has become widely recognized due to an increased clinical awareness of the disorder and to improvements in diagnostic techniques. In addition, the growing use of percutaneous liver puncture for the diagnosis of and therapy for hepatobiliary diseases and the increased incidence of both blunt and penetrating hepatic trauma have contributed to a rising incidence of hemobilia. We review the history, pathophysiology, and current approaches to the diagnosis and treatment of this disease.     

Promising techniques for breast cancer detection,diagnosis, and staging using non-ionizing radiation imaging techniques

Traditional imaging for the diagnosis and staging of breast cancer has relied on the tissue morphology of cancers in the background of normal patterns of fibroglandular breast tissue. X-ray mammography and ultrasound have been the primary modalities for the diagnosis and the work-up of breast cancer. New modalities have been validated including magnetic resonance imaging (MRI) and positron emission tomography (PET). New pulse sequences in MRI combined with contrast enhancement kinetic perfusion curves have greatly enhanced detection of mammographically occult cancers. New modalities on the horizon include optical imaging, exploiting again the differential perfusion properties of cancers in a background of normal glandular tissue. Even more specificity can be ach eved with the addition of ductal or intravenous introduction of optical probes specific to tumor associated antigens such as the HER-2/neu receptor in aggressive breast cancers. Quantum dots and other fluorescent dyes coupled to peptides or other probes will greatly enhance our ability to detect cancers earlier and without ionizing radiation.     

The necessity of complex use of radiation and endoscopic techniques in the differential diagnosis of gastric ulcerations

The results of examination of 156 patients were used to consider whether radiation and endoscopic techniques might be used in the differential diagnosis of gastric ulcerations. The necessity of their complex use is shown. Evidence is provided for that the understanding of intramural changes at the site of ulceration should underlie the interpretation of visual changes in the gastric mucosa. An algorithm has been developed for the rational and effective use of radiation and endoscopic techniques in the differential diagnosis of gastric ulcerations. The algorithm is shown to be highly effective in the correct interpretation of the pattern of an identified ulceration (98.4% specificity). Ultrasound and computed tomographic semiotics of benign and malignant gastric ulcerations is presented.     

Carcinoma of the nasopharynx; treatment with radioactive cobalt

A specific and characteristic type of anemia is not a feature of all malignant disease. To the contrary, the nature of the anemia will depend upon the causative mechanism, of which blood loss and accelerated erythrocyte removal appear to be the most frequently seen and the most clearly defined. Recognition of anemia due to loss of blood is relatively simple if the subtlety of blood loss in the stool is borne in mind and persistent testing to demonstrate it is carried out. Indeed, anemia characterized by chronic loss of blood in men can only mean chronic gastrointestinal bleeding if certain rare hemoglobin abnormalities can be ruled out. Anemia due to accelerated erythrocyte removal may also be recognized by simple measures. After transfusions raise hemoglobin values to near normal levels, the disappearance of the transfused blood and the rapid return of the pretransfusion severity of anemia are good evidence of the presence of such a mechanism, if blood loss can be ruled out.Adequate management of the anemia of malignant disease depends upon a clear understanding of the various mechanisms involved. It is highly probable that attention to this feature will, in many instances, significantly prolong the productive life of persons with malignant disease.     

A framework for the implementation of new radiation therapy technologies and treatment techniques in low-income countries

We present a practical, generic, easy-to-use framework for the implementation of new radiation therapy technologies and treatment techniques in low-income countries. The framework is intended to standardize the implementation process, reduce the effort involved in generating an implementation strategy, and provide improved patient safety by reducing the likelihood that steps are missed during the implementation process. The 10 steps in the framework provide a practical approach to implementation. The steps are, 1) Site and resource assessment, 2) Evaluation of equipment and funding, 3) Establishing timelines, 4) Defining the treatment process, 5) Equipment commissioning, 6) Training and competency assessment, 7) Prospective risk analysis, 8) System testing, 9) External dosimetric audit and incident learning, and 10) Support and follow-up. For each step, practical advice for completing the step is provided, as well as links to helpful supplementary material. An associated checklist is provided that can be used to track progress through the steps in the framework. While the emphasis of this paper is on addressing the needs of low-income countries, the concepts also apply in high-income countries.     

Use of exogenous electric current in the treatment of delayed lesions in peripheral nerves

A commonly observed clinical problem following nerve injury is the incomplete recovery of function associated with the formation of a neuroma in continuity. In the present study, exogenous direct electric current was tested for its ability to promote growth of axons through a neuroma-like lesion. Neuroma-like structures were created by crushing rat sciatic nerves at two sites 4 mm apart and applying phenol to the intermediate region. A bulbous axonally impenetrable structure is formed 3 weeks later. At that time, silicone cuffs were sewn onto the nerve proximal to the phenol application site and 7 mm distally. In experimental groups, cuffs were attached to wires leading to a subcutaneously implanted Traxon power source, the distal cuff being cathodal. In control groups, cuffs were not electrically connected. In electrically active groups, substantial numbers of myelinated axons were seen distal to the cathode 3 weeks after implantation. Four times fewer fibers were observed in control groups. Footprint patterns from electrically active animals revealed a significant improvement over control neuroma preparations, as quantitated using the Sciatic Functional Index.     

Stereology techniques in radiation biology

Clinicians involved in conventional radiation therapy are very concerned about the dose-response relationships of normal tissues. Before proceeding to new clinical protocols, radiation biologists involved with conformal proton therapy believe it is necessary to quantify the dose response and tolerance of the organs and tissues that will be irradiated. An important focus is on the vasculature. This presentation reviews the methodology and format of using confocal microscopy and stereological methods to quantify tissue parameters, cell number, tissue volume and surface area, and vessel length using the microvasculature as a model tissue. Stereological methods and their concepts are illustrated using an ongoing study of the dose response of the microvessels in proton-irradiated hemibrain. Methods for estimating the volume of the brain and the brain cortex, the total number of endothelial cells in cortical microvessels, the length of cortical microvessels, and the total surface area of cortical microvessel walls are presented step by step in a way understandable for readers with little mathematical background. It is shown that stereological techniques, based on a sound theoretical basis, are powerful and reliable and have been used successfully.     

Use of DNA probes in the diagnosis and treatment of periodontitis --a case series

Aggressive periodontitis is characterized by rapid attachment and bone loss with no underlying systemic disease and is associated with specific bacteria like Actinobacillus actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg). In this case series 25 patients were diagnosed with aggressive periodontitis by the aid of DNA probes for Aa and Pg and other periodontal pathogens. The use of DNA probes for the detection of periodontal pathogens may aid in the diagnosis and treatment of aggressive periodontitis. Clinical experience suggests that lowering periodontal pathogens to undetectable levels could improve the long-term stability of periodontal health.     

Molecular mechanisms of medullary thyroid carcinoma: current approaches in diagnosis and treatment

Medullary thyroid carcinoma is the most common cause of death among patients with multiple endocrine neoplasia (MEN) 2. Dominant-activating mutations in the RET proto-oncogene have been shown to have a central role in the development of MEN 2 and sporadic medullary thyroid cancer (MTC): about half of sporadic MTCs are caused by somatic genetic changes of the RET oncogene. Inactivating mutations of the same gene lead to Hirschprung disease and other developmental defects. Thus, RET genetic changes lead to phenotypes that largely depend on their location in the gene and the function and timing of developmental expression of the RET protein. The reproducibility of the phenotype caused by each RET genotype led to MEN 2/MTC being among the first conditions in Medicine where a drastic measure is applied to prevent cancer, following genetic testing: thyroidectomy is currently routinely done in young children that are carriers of MTC-predisposing RET mutations. RET inhibitors have been also developed recently and are used in various types of thyroid and other cancers. This report reviews the RET involvement in the etiology of MEN 2 and MTC and updates the therapeutic approach in preclinical and clinical studies.     

European audit of current practice in diagnosis and treatment of childhood growth hormone deficiency

BACKGROUND: The present survey among members of the ESPE on current practice in diagnosis and treatment of growth hormone (GH) deficiency (GHD) is of great clinical relevance and importance in the light of the recently published guidelines for diagnosis and treatment of GHD by the Growth Hormone Research Society. We have found much conformity but also numerous discrepancies between the recommendations of the Growth Hormone Research Society and the current practice in Europe. RESULTS: We found that 80% of the pediatric endocrinologists included insulin-like growth factor I (IGF-I) in their initial evaluation of a short child suspected of having GHD, whereas only 22% used GH provocative testing alone in the initial evaluation of a short child. Sixty-eight percent confirmed the diagnosis of GHD using two separate provocative tests. In the present survey cutoff values for GH provocative testing clustered around two values; 10 ng/ml and 20 mU/l. Interestingly, these two values, differing by a factor of 2, were also the most prevalent cutoff values among those who reported their assay to be calibrated against the WHO International Reference Preparation 80/505 where the conversion factor between milligrams and milliunits is 2.6. This suggests that the selection of cutoff values is based on tradition rather than on specific GH assay characteristics. In addition, only 63% of the respondents actually knew what GH assay they were using, and only 57% knew how their GH assay was calibrated. Dosing of GH at the start of treatment was reported according to body surface by 39%, whereas 59% were dosing according to body weight. GH dose adjustment was primarily based on growth response and height during auxological assessment every 3-4 months (height velocity, change in height velocity or change in height standard deviation scores) as indicated by almost 70% of the respondents. However, dose adjustment according to body surface (38%) and body weight (44%) was also quite common. Sixty-five percent measures IGF-I regularly (at least once a year) during GH therapy in children, and to our surprise 17% reported that they adjust the GH dose according to the IGF-I levels. SUMMARY: In summary, we have found large heterogeneity in the current practice of diagnosis and treatment of childhood GHD among European pediatric endocrinologists. Especially standardizations of GH assays and cutoff values are urgently required to ensure a uniform and correct diagnosis and therapy of GHD in the future.