Biomedical subjects

U Engelmann

Publications and source records attributed to U Engelmann.

At least 91 records · Page 5Linked to original sources

PubMed1997

Expression of immunohistochemical markers (PCNA, Ki-67, 486p and p53) on paraffin sections and their relation to the recurrence rate of superficial bladder tumors.

We present a retrospective study using four different immunohistochemical markers (PCNA, Ki-67, 486p and p53) on paraffin sections from 104 selected cases with primary superficial transitional cell carcinomas of the bladder (59 cases pTa, 45 cases pT1, 40 cases G1, 64 cases G2). 53 of the 104 patients experienced recurrence of their bladder lesion, while 51 remained free of tumor. The distribution of staging, grading and multifocality was comparable in both groups of patients. Overall, the tumors that recurred had a significantly higher proportion of labeled cells for PCNA (p < or = 0.0001), Ki-67 (p < or = 0.006) and 486p (p < or = 0.0001). The latter antigen proved to be the most reliable marker. A less significant difference in staining pattern was found for p53 (p < or = 0.01). Evaluating the predictive value of the various antibodies separately for the groups with G1 vs. G2 carcinomas and pTa vs. pT1 tumors revealed a lower significance for all antibodies. The technique of immunostaining on paraffin sections facilitates further retrospective studies on archival material. These markers may provide additional information about the probability of recurrence of superficial bladder tumors. But at the moment they should only be utilized in selected cases.

Adult↗

PubMed1996

[The determination of patient satisfaction as a part of quality management in the hospital].

BASIC PROBLEM AND OBJECTIVE OF STUDY: Patient-satisfaction is an important part of the quality of results of medical treatment in hospital. Such satisfaction can be measured with a standardised multi-dimensional questionnaire which takes into account all relevant parts of a hospital. An enquiry was undertaken on patients in a university department of urology to find out whether a scientifically based measurement of patient-satisfaction is possible and whether organisational improvement can result from it. PATIENTS AND METHODS: Dimensions of patients-satisfaction included "care by doctors", "care by nursing staff", "food and accommodation", and "administration and daily activity". A questionnaire with a scale for answers (total of 65 items with closed answers) was developed for each of the dimensions. A one-month pretest served to ascertain acceptance and understanding of the questionnaire. In the three-month main test period questionnaires were given to all in-patients over 16 years old on admission. Participation was voluntary and anonymous. RESULTS: 232 patients took part (172 men, 60 women; median age 57 years), a response rate of 61%. The scales were shown to have a high internal consistency. The answers provided, for example, the means for simple and directly applicable improvement in patient information and the organisation of daily routine. Making the results known had a positive effect on the motivation of the staff. CONCLUSION: The work and cost involved in such a study are reasonable. This is the more so since in future investigation on patient-satisfaction will be undertaken every year or two as part of the demanded quality management in hospitals. However, scientific principles in the methodology must be taken into account when evaluating the results.

Adult↗

PubMed1996

First temporal and spatial quantification of single-shot electrohydraulic lithotripsy in vitro.

Single electrohydraulic lithotripsy (EHL) discharges from a human ureter were analyzed with a mechanical high-speed motion analysis camera. We found a cavitation bubble, at 650 mJ, 4-11 mm in size, with a lifetime of 400-500 microseconds. Varying sizes and lifetimes were found using single-shot analysis, as well as in different shot-sequences. This supports similar observations by recent investigations of cavitation bubble size with high-shutter-speed videofilm, which have depicted events at shutter speeds of 4000/s, i.e., an approximate exposure time of 250 microseconds. Due to the occurrence of high-voltage interference from the EHL high-voltage generator, no other technical electronic event timing equipment has so far been available capable of mechanical high-speed film motion analysis, while at the same time avoiding high-voltage interference.

Lithotripsy↗

PubMed1996

Recurrent bleeding of angiomyolipomas in tuberous sclerosis.

The diagnostic and therapeutic problems of renal hamartomas are illustrated by a case of recurrence of bleeding angiomyolipomas associated with tuberous sclerosis. Ultrasound and computed tomography provide clear evidence of lipomatous formation while, in rare instances, angiography can demonstrate the existence of multiple vascular tumor compartments. In view of the risk of bleeding, multiple or very large angiomyolipomas should be treated by interventional radiology in the form of superselective tumor embolization or by the most conservative surgery possible.

Adult↗

PubMed1996

Testicular tissue oxygen pressure.

PURPOSE: We evaluate the feasibility of continuous, intratesticular tissue oxygen pressure (IT-pO2) measurement under various conditions. MATERIALS AND METHODS: Flexible, polarographic microcatheter systems (1.5 F) for continuous pO2 measurements have been used. The measurements were conducted on 37 adult male albino rats. The probes could be placed intratesticularly under controlled temperatures by microsurgical techniques. The IT-pO2 of the ipsilateral and contralateral testicle was determined after unilateral torsion. Furthermore the influence of intratesticular temperature on IT-pO2 was determined. RESULTS: Intratesticular pO2 was found to be 21 +/- 5 mm.Hg under normal conditions. Under complete ischemia, pO2 dropped within 3 to 5 minutes to a level of approximately 1 mm.Hg. A counterclockwise unilateral testicular torsion of 720 degrees led to a decrease of the IT-pO2 within 5 to 7 minutes to 5 +/- 1.5 mm.Hg. After detorsion the IT-pO2 recovered within 15 minutes, while the IT-pO2 of the contralateral testicle remained unchanged. Simple surgical exposure of the testicle led to a reversible decrease of the intratesticular pO2 to 7 +/- 2.5 mm.Hg correlating with an intratesticular temperature decrease from approximately 31.5 to 23.5 C. CONCLUSIONS: The measurements are feasible and may provide a continuous intraoperative assessment of intratesticular oxygen pressure. The contralateral IT-pO2 after unilateral torsion remained unchanged. The IT-pO2 and testicular blood flow depend, if the utilization of oxygen is unchanged, on intratesticular temperature.

Animals↗

PubMed1996

[Compartment syndrome: a complication of lithotomy position].

Urological operations are commonly performed in the lithotomy position. A rare, but serious, complication is the compartment syndrome, which can result in neurovascular damage and permanent disability or limb loss. We describe two cases of compartment syndrome. One arose after transurethral resection of the prostate, and the other after an operation to change a transsexual patient from man to woman. The literature is reviewed, and the causes of the syndrome and possible ways of preventing serious consequences to the patients affected are discussed.

Adult↗

PubMed1995

The image related services of the HELIOS software engineering environment.

This paper describes the approach of the European HELIOS project to integrate image processing tools into ward information systems. The image processing tools are the result of the basic research in image analysis in the Department Medical and Biological Informatics at the German Cancer Research Center. These tools for the analysis of two-dimensional images and three-dimensional data volumes with 3D reconstruction and visualization ae part of the Image Related Services of HELIOS. The HELIOS software engineering environment allows to use the image processing functionality in integrated applications.

Computer Communication Networks↗

PubMed1995

Efficacy of local Bacillus Calmette-Guérin treatment in superficial bladder cancer relapsing under Keyhole-Limpet Hemocyanin immunotherapy.

The efficacy of local immunotherapy with Keyhole-Limpet Hemocyanin (KLH) and Bacillus Calmette-Guérin (BCG) in preventing recurrence of superficial bladder cancer (stages pTa to pT1; grades 1 to 3) was checked in 96 patients. All tumours were resected and all patients were presumed to be free of malignant disease at initiation of prophylactic KLH instillations. Before starting KLH instillations (20 mg/administration week for 6 weeks, followed by regular (bi)monthly instillations for 3 years altogether) all patients were intracutaneously immunized with 1 mg KLH. Tumour relapse under this therapeutic schedule was the indication for BCG instillations (120 mg BCG-Connaught; administration in analogy to KLH treatment). This study has proved that (1) prophylactic KLH treatment reduced superficial bladder cancer relapse rate after surgical intervention without considerable local/systemic side effects and (2) local BCG-administration was therapeutically effective in relapsing/progressive disease under KLH treatment. There were, however, pronounced side effects.

Adjuvants, Immunologic↗

PubMed1995

Immunohistological findings in patients with superficial bladder carcinoma after intravesical instillation of keyhole limpet haemocyanin.

OBJECTIVE: To determine whether keyhole limpet haemocyanin (KLH) instilled intravesically improves the local cellular response within the bladder wall of patients suffering from superficial bladder carcinoma. PATIENTS AND METHODS: Twelve patients (10 men and two women, mean age 67 years, range 42-85) with superficial carcinomas of the bladder were treated for 6 consecutive weeks and then monthly for 1 year with 20 mg KLH in 20 mL saline instilled intravesically after complete resection of the tumours. Biopsies were taken for immunohistochemical examination before treatment and again 6 weeks, 3, 6 and 9 months after treatment. Six patients with no evidence of cystitis or malignant bladder disease acted as a control group. Immunofluorescent staining of the biopsies was performed using monoclonal antibodies to the T-cell markers CD4 and CD8, and to CD14 (monocytes), CDw15 (granulocytes), CD19 B-cells (Pan-B), CD68 (macrophages) and HLA-DR. Anti-KLH antibody-producing plasma cells were detected using a standard technique. A semiquantitative analysis of locally infiltrating cell types was performed. RESULTS: After treatment with KLH the increase of CD8+ suppressor cells was less pronounced than that of CD4+ helper cells. The T-helper/inducer to T-suppressor/cytotoxic cell ratio thus altered from 0.8:2.0 before treatment to 1.6:2.3 afterwards. Hence, the number of T-helper cells had increased considerably, whereas there was only a moderate increase in the number of T-suppressor cells. This cellular ratio could be detected for 9 months after KLH therapy. The numbers of activated HLA-DR+ immune cells in the submucosa and among urothelial cells also increased after KLH instillation. The degree of mononuclear cell infiltration of the submucosa increased considerably, but granulocyte infiltration was only moderate. Lymph follicles with enhanced B-lymphocyte counts were also detected. CONCLUSION: Immune-cell infiltration into the urothelium and enhanced activation (expression of class II antigens) suggests distinct processes of cellular antigen recognition, which could be detected for up to 9 months after the beginning of KLH therapy. This may represent a basic functional mechanism of KLH therapy.

Administration, Intravesical↗

PubMed1995

[Current trends in clinical urology].

Many recent developments in urologic diagnostic and therapy are also of interest for general surgeons. Flexible and semirigid ureteroscopes (6-8 F) provide easy and atraumatic access to the whole upper urinary tract. Beside extracorporeal shockwave-lithotripsy now various endourologic modalities to treat ureteral stones are available. Although useful, laparoscopic techniques are not yet widely accepted by urologists because there is a lack of indications in urologic laparoscopic surgery. The functional reconstruction of the urinary bladder by means of an ileal neobladder with an anastomosis to the urethra in the male or with a continent stoma and selfcatheterism provides better quality of life in patients after radical cystectomy. Nephron-sparing tumor surgery may become a routine procedure under certain precautions such as small tumor size, patient's compliance and good local medical infrastructure. Especially for urologic microsurgery, neurourology and different treatments of benign prostatic hyperplasia essential new and interesting improvements are expected.

Female↗

PubMed1995

[Follow-up of contralateral intratesticular oxygen pressure in unilateral testicular torsion].

The intratesticular tissue oxygen tension (= IT-pO2) depends on the testicular perfusion. Polarographic microcatheter probes have recently become available and are suitable for continuous measurements of the tissue oxygen tension. In 20 adult albino rats flexible Clark-type oxygen electrodes (1.5 F) were used for simultaneous monitoring of IT-pO2 of the ipsi- and contralateral testicle during unilateral torsion. A counterclockwise 720 degrees torsion caused a decrease of IT-pO2 from 21 mm Hg (+/- 5 mm Hg) to 5 mm Hg (+/- 1.5 mm Hg) in the twisted testicle within 5-7 min. After detorsion the IT-pO2 returned to normal level in the following 25 min. The IT-pO2 of the contralateral testicle showed no significant changes during torsion for 1 h or after detorsion. Thus, if the oxygen utilization is unchanged a unilateral acute torsion for 1 h does not cause a decrease in perfusion in the contralateral testicle. It will probably also prove possible to use oxygen tissue tension measurements to improve our understanding of testicular perfusion in humans.

Animals↗

PubMed1995

Impact of shock wave pattern and cavitation bubble size on tissue damage during ureteroscopic electrohydraulic lithotripsy.

It is known that electrohydraulic lithotripsy (EHL) during ureteroscopy may cause ureteral damage. To evaluate this trauma potential, find its mechanism and make it possible to avoid it, our research employed photographic evaluation, tissue studies, shock wave measurements and disintegration tests. The setup included a 3.3 F probe attached to an experimental generator with adjustable voltages and capacities providing energies from 25 mJ. to 1300 mJ. per pulse. In general, we distinguish between two traumatic mechanisms: (1) After placing the probe directly on the mucosa the rapid initial plasma penetrates the tissue resulting in a small, nonthermal, punched-like defect, whose depth depends on the energy applied. This trauma has minor clinical implications and is avoided by maintaining a minimum safety distance of 1 mm.; (2) According to physics, each plasma is followed by a cavitation bubble. The maximum size of this bubble depends on the energy applied and ranges from 3 mm. (25 mJ) to > 15 mm. (1300 mJ). In proportion to the bubble size, the ureteral wall may be distended or disrupted, even when the probe is not in direct contact with the mucosa. Therefore, the goal should be to obtain a low energy pressure pulse with high disintegration efficacy. Our evaluation of the pressure waves revealed that the selection of a high voltage and a low capacity leads to short and steep "laser-like" pulses. These pulses have a significant higher impact on stone disintegration than the broader pulses of the same energy provided by currently available generators.

Biophysical Phenomena↗

PubMed1995

Integrated image processing in clinical applications: the HELIOS approach.

This paper describes the approach of the European HELIOS project to integrate image processing tools into ward information systems. The image processing tools are the result of the basic research in image analysis in the Department Medical and Biological Informatics at the German Cancer Research Center. Tools for the analysis of 2-dimensional images and 3-dimensional data volumes with 3-dimensional reconstruction and visualization are part of the Image Related Services of HELIOS.

Europe↗

PubMed1994

The HELIOS medical software engineering environment.

The aim of the HELIOS project is to create an integrated Software Engineering Environment (SEE) to facilitate the development and maintenance of medical applications. HELIOS is made of a set of software components, communicating through a software bus called the HELIOS Unification Bus. The object oriented paradigm is used both as the basic structure for building the software components and as the methodology for modelling, storing and retrieving the entities and procedures used in an application. Development standards include UNIX as operating system and X Window/MOTIF as windowing environment. One of the target applications for the HELIOS prototype is the development of a multimedia medical workstation as a front end to a hospital information system.

Computer Systems↗

PubMed1994

[Value of endoluminal high-resolution ultrasound in urology].

The clinical use of endoluminal high resolution ultrasound in urology was investigated in 14 patients using miniature transducer-containing catheters (20 MHz 8 F and 10 MHz 10 F). For imaging the ureter, an 8 F flexible ultrasound probe was used. Using this technique, exact 360 degrees cross sections of the ureter and periureteral tissue were obtained. Differentiation between normal and abnormal structures including embedded stones and aberrant vessels is possible and impacts on surgical approach. Wall thickness of the ureterovesical junction was observed in patients with vesicoureteral reflux compared to the other patients. Therefore, a reliable measurement and differentiation of anatomical structures in the urinary tract was possible. The 20 MHz device revealed a better discrimination of anatomical and pathological structures than the widely used systems with lower frequencies e.g. 10 MHz. However, for the exact staging of superficial urothelial carcinomas, the method failed. Ultrasound devices with higher frequencies, e.g. 30 MHz and more, will most likely allow a more exact staging of these tumours.

Adult↗

PubMed1994

Nephrogenic adenoma of the bladder.

A nephrogenic adenoma of the bladder in a 4-year-old girl with a past history of urologic surgery for vesicorenal reflux is described. The multifocal tumor was treated by transurethral resection. Relapse occurred 15 months later and was again treated by transurethral resection. Pathological aspects, clinical features and therapeutic considerations of this proliferative lesion are reviewed and discussed.

Adenoma↗

PubMed1994

The component-based architecture of the HELIOS medical software engineering environment.

The constitution of highly integrated health information networks and the growth of multimedia technologies raise new challenges for the development of medical applications. We describe in this paper the general architecture of the HELIOS medical software engineering environment devoted to the development and maintenance of multimedia distributed medical applications. HELIOS is made of a set of software components, federated by a communication channel called the HELIOS Unification Bus. The HELIOS kernel includes three main components, the Analysis-Design and Environment, the Object Information System and the Interface Manager. HELIOS services consist in a collection of toolkits providing the necessary facilities to medical application developers. They include Image Related services, a Natural Language Processor, a Decision Support System and Connection services. The project gives special attention to both object-oriented approaches and software re-usability that are considered crucial steps towards the development of more reliable, coherent and integrated applications.

Computer Communication Networks↗

PubMed1994

The HELIOS Medical Connection Services.

This paper presents the design and implementation of the HELIOS software component that deals with integration of medical applications in health information networks. The problem of interoperability between health information systems based on different data exchange syntaxes is first discussed. A meta-model, relying on CEN TC251 recommendations, is then presented as a possible solution to this problem and a message description language including these recommendations is proposed. Using this meta-model, the Medical Connection Services that comprises a generic message processing automaton, a resource manager and a mapper is able either to interpret messages expressed in a given syntax (e.g., EDIFACT, ASTM) and map them to the application objects or to automate the translation of the messages in another syntax. Special focus is given on the position of the Medical Connection Services within the HELIOS integration strategy (i.e., through data, presentation and communication). The problem of semantic heterogeneity is then discussed.

Computer Communication Networks↗