Biomedical subjects
Publications and source records attributed to J Vogel.
The radiological appearance of 6 posterior epidiaphragmatic fatty tissue masses in MRI and CT is reported. The differential diagnostic considerations of lipoma, herniation or dystopia and the value of imaging techniques are discussed.
DNA measurements in renal cell carcinoma are demonstrating a considerable tumor heterogeneity. Tumor DNA content is one of important prognostic factors. Renal cell carcinomas can be divided into two main groups by single-cell cytophotometry: diploid/near diploid in grade 1 and 2 and mainly aneuploid in grade 3 with variable blocks and peaks. In different tissue samples from the same carcinoma we can found different polymorphism and DNA content.
According to their different etiology, parapelvic cysts must be differentiated from simple renal cysts, pararenal pseudocysts, intramural renal pelvis cysts and suprarenal pseudocysts. An important criterium of parapelvic cysts is their epithelial lining. According to their radiological features, these cysts must be described as "parapelvically located cysts" until the definite histological diagnosis is made by the pathologist. The exact differentiation between a parapelvic cyst and a pararenal pseudocyst may be of forensic importance in posttraumatic patients.
An understanding of the pathogenesis of human viral diseases has been hampered by the lack of suitable animal models. However, with the advent in the last decade of transgenic technology, it is now possible to introduce one or more viral genes into the germ-line of animals. Thus, transgenic technology allows for the study of viral gene expression and function in the context of the whole animal. The focus of this review is to define the advantages and disadvantages of the transgenic approach in studies of viral pathogenesis. Studies involving a human DNA tumor virus (JCV) and a human retrovirus (HIV) will be described to illustrate these points.
The aggressive fibromatosis is a surgical problem disease. Two remarkable cases serve as examples to demonstrate the aggressive forms of extraabdominal fibromatosis. There is a tendency to locally invasive destructive growth without metastasising at any time and a markedly high relapse rate after surgery, a tendency that showed up clearly in our patients, too. The very multivarious nomenclature points out that about histiogenesis, pathogenesis and benignity of this excrescence still exists great obscurity. We report on the pathology and clinic of an aggressive fibromatosis of the thyroid gland region and of a thoracal aggressive fibromatosis in the right shoulderblade-region.
To obtain data on the volume-dependence of the oscillatory parameters of the Siregnost FD 5, we investigated the course of iso-volume and iso-resistance lines in a simple mechanical resistor-volume model in the different coordinate systems, initially in the absence of additional superimposed stationary flow. While the P-psi diagram reveals no uniform course, and no preferential relationship of changes in resistance to P or Ros, or of changes in volume to psi, such a relationship develops on transformation to the Rre-phi and the Rre-X diagram. Rre proves to contain not only the purely resistor component, but also a reactance-proportional or inversely volume-proportional component, which is apparently due to internal friction resulting from volume compression. On the other hand, reactance is almost totally derivable from volume compression. With reference to the theoretical Franken model and others (1981), we discussed the influence of various physical factors on the impedance of a tube segment, and the different volume-dependence of impedance of closed- and open-ended cylindrical tubes. Further work on the theoretical consideration of the forced oscillation technique will examine the influence of additional superimposed stationary flow, which has a considerable effect on the resistor-volume model. Furthermore, the critical value of Reynold's number may be expected to be exceed in the FD 5 reference tube already at low respiratory flow.
Against the background of the working hypothesis of the 1-parametric Siregnost FD 5 forced oscillation technique-phase angle psi may be invariant in a clinical reference population-the hypothetical straight Ros-P line is in good agreement with the crowd of extremely nonlinear Rre-P-lines only within narrow limits. Neglecting phase angle measurements it might be useful to insert a known linear resistor into the airway to determine the pertaining Rre-P relation. In spite of selective tuning to the oscillation frequency of 10 Hz there is full sensitivity to stationary flow; alinear stationary flow characteristics of resistors can be readily determined by forced oscillation. There is a marked improvement in the P-psi/Rre-phi-evaluating system with respect both to the symmetry of phase angle and unequivocality of pressure when the reference phase angle alpha is shifted from 81 degrees to 0 degrees. Using digital data acquisition and processing, a flexible evaluation technique with monitor-oriented test management, automatical calculation of secondary values and multidimensional presentation of results on a graphical display is provided, which has proved its worth in experimental and clinical-physiological studies.
The practical application of the forced oscillation technique for the analysis of the mechanics of respiration is hampered by the fact that the measured frequency-dependent impedance values R(f) and X(f) cannot be related directly to the parameters airway resistance Raw and pulmonary compliance CL. Furthermore, various derived oscillatory parameters are employed which are not directly comparable even with one another. In order to be able to estimate the diagnostic relevance and comparability of the impedance curves R(f) and X(f), their form-specific characteristics R = R(5)-R(20) and X(5), as also the equipment-specific parameters Ros (Siregnost FD5) and Rfo (custo vit), the relationships of these oscillatory parameters to Raw and CL were simulated in a structural model of the respiratory system, and tested in the real system. It was shown that already from frequencies of f greater than 10Hz upwards, R(f) no longer reacts to an increase in resistance in the peripheral region of the lung, and at 20 Hz indicates only the upper airway component of a global obstruction demonstrated body-plethysmographically with Raw. The diagnostic information on peripheral airway obstruction is contained in both components R(f) and X(f) of the respiratory impedance; with increasing obstruction and increasing frequency, it progressively reverts to the X(f) curve. Therefore, by including X(f) in the resistance evaluation for the parameters Ros and Rfo, the underevaluation of R(f) as compared with Raw can in part be compensated for, although an overe stimation at low Raw values with Ros and a large scatter of the Rfo values in the case of large Raw figures has to be accepted.(ABSTRACT TRUNCATED AT 250 WORDS)
In patients with chronic obstructive airway disease, comparative examinations using body plethysmography were performed with a view to evaluating the effectiveness of two forced oscillation techniques, fixed-frequency and poly-frequency techniques in estimating disorders of respiration mechanics. At slight and moderate elevations in bronchial flow resistance, a better agreement was found between the custo vit resistance figure and body plethysmography. A differentiation of healthy subjects from patients with low-grade obstruction by means of the FD 5, requires the establishment of the phase angle (phi), too, while in the case of the custo vit unit, this is possible by demonstrating the frequency dependence of the impedance. Patients with more severe disease with secondary emphysematous changes, reveal a clear difference between the phase signal (psi) primarily measured on the FD 5, and the phase angle. Forced oscillation usefully supplements spirometery in the respiratory basic diagnostic work-up employed through-out treatment. Fixed-frequency techniques require the determination of the phase angle for assessment of peripheral obstructions; the advantage of the poly-frequency technique can be seen in the largely specific demonstration of the frequency dependency of the resistance.
In three groups of healthy subjects and patients with pulmonary fibrosis or pulmonary emphysema, the secondary periodical oscillatory phenomena observed under conditions of normal breathing and a slow VC manoeuvre on the Siregnost FD 5 were broken down into a volume- and a flow-synchronous component, as also a third component with no correlation with either volume or flow, and which can be observed in the primary parameters Ros and psi, as also the secondary parameters Rre and phi. While both fibrotic patients and healthy subjects revealed a volume-inverse phase behaviour, patients with pulmonary emphysema revealed a volume-proportional phase behaviour. This difference in volume dependence is explained by the difference in elastic recoil in patients with fibrosis as compared with those suffering from emphysema, and the associated different influence on the filling of the lungs with air and blood.
With the aim of determining the significance of the principle of the multi-frequency forced oscillation technique employed by the custo vit to determine the airway resistance, measurements were performed on a number of test subjects, employing a unit available with three different software modifications. A comparison with the resistance values obtained with other equipment (whole-body plethysmograph, Siregnost FD5), revealed the diagnostic usefulness of the technique of frequency-dependent resistance. It was also confirmed that the phase angles, also obtainable with the custo vit, play a considerable role in the significant differentiation of the degree of obstruction. The differences in comparison with other methods are critically examined, and proposals made for a further improvement of the forced oscillation technique employed by the custo vit.
A case of a 40-year-old man with an adreno-cortical ectopia in the region of the spermatic cord is presented. The genesis and complexity of this anomaly is discussed. The seldom occurring, but sometimes important clinical relevance of these ectopies is demonstrated.
We report the not-yet-published case of a renal cell carcinoma in an atrophic kidney in combination with ipsilateral pheochromocytoma and adrenal cortex hyperplasia. The cause of the adrenal cortex hyperplasia was found to be the result of a reaction to the accompanying adaptation hyperplasia.
We report the case of an 86-year-old female with an unremarkable past history who suddenly developed severe and generalized bleeding. Laboratory work-up revealed prolonged aPTT, a factor VIII level of 7% and the presence of a factor VIII inhibitor. In spite of whole blood, factor VIII concentrates and immunoglobulin administration, the patient died of multiple hemorrhages on the third day after admission. At autopsy no causal or associated pathology could be found. Chromatographic separation of plasma immunoglobulins showed that the anti-factor VIII activity was associated with the patient's IgG. This inhibition was partially corrected in vitro by injectable immunoglobulin preparation. The case report stresses the discrepancy between the measured levels of inhibitor and the severity of the bleeding; our in vitro results may shed light on the mode of action of intravenous immunoglobulins.
When the human immunodeficiency virus transactivating gene under the control of the viral regulatory region is introduced into the germline of mice, skin lesions are induced that resemble Kaposi's sarcoma seen in AIDS. Our findings indicate that HIV could play a direct part in causing cancer.
This retrospective study analyses the fate and associated risk factors of 99 patients who underwent laparotomy for hepatic trauma from 1977 to 1986. Blunt trauma (88 patients) and stab wounds (7 patients) had mortality rates of 36 and 14 per cent respectively. The overall death rate was 35 per cent. Multiple trauma patients had a significantly higher mortality for each additional system that was seriously injured. Pre-operative shock raised the mortality from 20 to 58 per cent (P less than 0.001). For patients over 50 years of age, the mortality rate increased from 30 (younger patients) to 63 per cent (P = 0.028). Minor hepatic wounds required relatively simple surgical measures in 60 patients, yet 13 died (22 per cent) of other causes. More sophisticated surgical management was applied to 27 major hepatic lesions, with 10 deaths (37 per cent). Twelve patients (seven with minor and five with major hepatic wounds) died before surgical treatment of the liver injury could be undertaken. The overall mortality rate of major hepatic wounds was 47 per cent and for minor wounds 30 per cent. However, the difference was not significant (P = 0.152). Resection was resorted to in 15 patients, 5 of whom subsequently died (33 per cent). Classical hepatic lobectomy led to 4 deaths (50 per cent). Among the 35 deaths, 6 were due to the hepatic trauma itself (5 exsanguinations and 1 intra-abdominal sepsis). Isolated hepatic injury was fatal in three patients. We believe that conservative surgical measures should be used whenever possible in patients with hepatic trauma, especially when risk factors are encountered.
The purpose of transgenic technology is to introduce a gene into the germline of an animal in order to investigate its proper expression in the appropriate cell types and its effect on cellular functions. This technology has been used to explore a wide variety of genetic and biological issues including stage- and tissue-specific gene expression, development, immunology, oncology, and gene therapy. The intent of this article is to discuss the value of gene transfer technology for the study of mechanisms of viral pathogenesis. We will focus mainly on our experience with two experimental systems involving human T-lymphotropic virus Type 1 (HTLV-1) and human immunodeficiency virus Type 1 (HIV-1).
For the treatment of cystic changes of the pancreas, it is essential to distinguish cysts and pseudocysts from neoplasm. Since clinical parameters are usually not characteristic, only histologic and cytologic analyses will prove a diagnosis. The immunohistochemical characteristics of microcystic adenoma, mucinous cystic neoplasia in comparison to solid cystic pancreatic tumor, ductal carcinomas, and endocrine tumors, are studied with a panel of markers as well as enzyme, epithelial, neuroendocrine and pancreatic hormonal markers. The immunohistochemical results with diffuse cytoplasmatic expression of CEA and epithelial markers may be helpful in the exploration of carcinomatous transformed tissue parts within mucinous cystic pancreatic neoplasias, and are therefore of significance for surgical therapy.