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Biomedical subjects

U Jonas

Publications and source records attributed to U Jonas.

At least 217 records · Page 12Linked to original sources
PubMed1992

[ESWL in hemophilia B].

One of the most dramatic dangers in treating nephrolithiasis by ESWL is the development of intra- and perirenal bleeding, which requires therapeutic intervention. Even in patients whose blood parameters suggest they are healthy, hematomas are found in up to 80%. Therefore, ESWL must be regarded as contraindicated in patients with blood disorders. A case of a patient suffering from hemophilia B and from a large renal pelvic stone is reported, whom we treated by ESWL twice after sufficient substitution. X-ray revealed that the patient was stone-free on the 25th day after the first ESWL session. ESWL. A review of the literature is presented.

Adult↗
PubMed1992

[Vasectomy: minor intervention--grave sequelae].

Claims for compensation following dissatisfaction with the results of medical treatment have increased in frequency over the last few years. Medical records, such as declarations of consent and operation reports, often constitute important evidence in legal proceedings, particularly in the field of surgery. Before a vasectomy is performed for the purpose of contraception, detailed information must be given on how safe this is as a method of birth control and the patient must be made aware of the importance of sperm count controls after the operation. The surgeon is held responsible if it can be shown that a failed sterilization is due to ligation of only one vas deferens or to failure to notice an accessory one. Claims for compensation can include support for children up to the age of 18 years and financial compensation to the mother in respect of the labour pains.

Humans↗
PubMed1991

In-vitro matured human macrophages express Alzheimer's beta A4-amyloid precursor protein indicating synthesis in microglial cells.

Microglia which are consistently associated with Alzheimer's disease (AD) senile plaques are part of the mononuclear phagocyte system. In-vitro matured human monocyte-derived macrophages feature many immunological characteristics of microglia. We found strong constitutive expression of Alzheimer's beta A4-amyloid precursor protein (APP) in human mononuclear phagocytes after terminal in-vitro maturation from monocytes to macrophages. Amyloid has previously been found to be associated with microglia in AD brains, however, it remained unclear whether the material was synthesized in or had been phagocytosed by the cells. The findings presented here support the assumption that brain microglia may contribute to APP synthesis in AD brain.

Amyloid beta-Peptides↗
PubMed1991

Alpha 2-macroglobulin synthesis in interleukin-6-stimulated human neuronal (SH-SY5Y neuroblastoma) cells. Potential significance for the processing of Alzheimer beta-amyloid precursor protein.

Cultured human neuronal (SH-SY5Y neuroblastoma) cells synthesize and secrete the potent protease inhibitor alpha 2-macroglobulin (a2M) upon stimulation with interleukin-6 (IL-6) indicating that alpha 2-macroglobulin behaves as an acute-phase protein in the human central nervous system. Exogenous addition of a2M to the cultured neuronal cells resulted in only a slight inhibition of Alzheimer beta A4-amyloid precursor protein (APP) synthesis, but markedly inhibited its secretion pointing to the possibility that a2M may affect the proteolytic APP processing. Evidence is provided that IL-6 and a2M are involved in Alzheimer's disease pathogenesis.

Alzheimer Disease↗
PubMed1991

Single potential analysis of cavernous electrical activity.

Recording of cavernous electric activity was performed in 178 patients with erectile dysfunction and in 37 normal patients. In 34/37 normal patients, potentials of a uniform shape were recorded during flaccidity: At cut-off frequencies of 0.5-500 Hz, the length was 8-18 (mean 12.8, SD 2.8), the amplitude 250-750 (mean 444, SD 109) microV, and the polyphasity 8-22 (mean 13.8, SD 3.3). In impotent patients with upper motor neuron lesions or peripheral lesions, specific types of potentials were observed. In 11/14 impotent patients with insulin-dependent diabetes for over 20 years and clinical findings of cavernous myopathy, potentials showed low amplitude, irregular shape, and slow depolarizations. In 51% of the consecutive impotent patients, abnormal findings of cavernous electric activity were recorded. Our clinical study suggests that single potential analysis of cavernous electric activity (SPACE) may be useful in the diagnosis of cavernous autonomic neuropathy and cavernous smooth muscle myopathy.

Action Potentials↗
PubMed1991

In vitro sensitivity testing of human renal cell carcinoma with cytostatic agents and interferon alpha-2a.

Samples of 38 human renal cell carcinomas (RCC) were subjected to routine histopathological examination but also to in vitro sensitivity testing with mitomycin C, vinblastine and interferon Alpha-2a at various concentrations corresponding to serum titers recommended to be effective in vivo, employing a monolayer assay. Extending earlier in vitro studies, both tumor cell kill rates (TCKR) and proliferation rates (PR) were assessed. Following in vitro preparation the tumor cell cultures were simultaneously exposed to the anticancer drugs listed above. The proliferation rates were determined immunocytochemically using the monoclonal antibody Ki-67. Nine (23.7%) of the tumors investigated revealed temporary and limited response with respect to either TCKR or PR. Improvement of this percentage could only be obtained by increasing drug concentration to titers with toxicity intolerable for in vivo administration. The in vivo data presented correspond to clinical temporary and limited remissions in patients with metastatic RCC ranging up to 25%.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

Metastatic renal cell carcinoma (RCC): spontaneous regression, long-term survival and late recurrence.

We report 4 cases of metastatic renal cell carcinoma (RCC) with long-term survival either following radical nephrectomy alone or in combination with radio- or hormonal therapy. Two patients with lymph node metastases showed a long-term survival of 12 or more years following radical tumour nephrectomy (with lymphadenectomy) and radiotherapy. One of them exhibited a histologically proven tumour recurrence nearly 12 years after primary surgical treatment and died shortly later; the other one is still without any evidence of metastatic disease. Two other patients exhibited spontaneous regression of pulmonary metastases: one regression occurred after radical tumour nephrectomy alone, the other one after successful primary hormonal treatment and subsequent radical tumour nephrectomy. The following important aspects are emphasized: 1. Renal cell carcinoma is a very unpredictable tumour. Once the diagnosis of renal cell carcinoma is proved, a patient can never be considered cured. 2. Although adjuvant palliative nephrectomy has produced contradictory results in several reports, radical tumour nephrectomy either alone or in combination with other adjuvant therapies such as radiotherapy, hormonal or immunological treatment, can be worthwhile. Cases with long-term survival and spontaneous regression of distant metastases are proof of this. Besides, if carefully selected, the mortality rate of different adjuvant therapies is not significantly higher in patients with metastatic disease than in patients without metastases. The world literature on this subject is reviewed.

Aged↗
PubMed1991

Single potential analysis of cavernous electrical activity in impotent patients: a possible diagnostic method for autonomic cavernous dysfunction and cavernous smooth muscle degeneration.

Cavernous electrical activity was recorded in 214 patients with erectile dysfunction and in 39 normal patients. In 34 of the 39 normal patients potentials of a uniform shape were recorded during flaccidity. At cutoff frequencies of 0.5 to 500 Hz. the duration was 8 to 18 seconds (mean 12.8 +/- 2.8, seconds, standard deviation), the amplitude was 250 to 750 microv. (mean 444 +/- 109 microv.) and the polyphasity was 8 to 22 (mean 13.8 +/- 3.3). With increasing tumescence and rigidity during audiovisual sexual stimulation, high frequency potentials of low amplitude and short duration were found in the normal patients. In impotent patients with an upper motor neuron or peripheral lesion specific types of potentials were observed. In 11 of 14 impotent patients with insulin-dependent diabetes for more than 20 years and with clinical findings of cavernous myopathy the potentials showed low amplitude, irregular shape and slow depolarizations. Abnormal findings of cavernous electrical activity were recorded in 51.6% of the consecutive impotent patients. Our clinical study suggests that single potential analysis of cavernous electrical activity may be useful in the diagnosis of cavernous autonomic neuropathy and cavernous smooth muscle myopathy.

Adult↗
PubMed1991

Calcitonin-gene-related peptide: a possible role in human penile erection and its therapeutic application in impotent patients.

A functional study was done to examine a possible role of calcitonin-gene-related peptide in human penile erection and its possible therapeutic applications for patients with erectile dysfunction. In the determination of an effective dosage, 5 ng. (2 patients), 50 ng. (2 patients), 500 ng. (4 patients), 5 micrograms (4 patients) and 25 micrograms (7 patients) were injected intracavernously, and pulse and blood pressure were monitored. Arterial inflow was measured by Doppler sonography, smooth muscle relaxation was determined by the analysis of cavernous electrical activity and cavernous outflow occlusion was recorded by cavernosometry. In 12 patients the erectile response of prostaglandin E1 was compared to the response of an equal (6 patients) or decreased dose of prostaglandin E1 combined with an equal weight of calcitonin-gene-related peptide. In 14 patients the erectile response to the combination of calcitonin-gene-related peptide and prostaglandin E1 was compared to the response of prostaglandin E1 alone, and with a combination of 15 mg./ml. papaverine and 0.5 mg./ml. phentolamine. Calcitonin-gene-related peptide induced an increase in the penile arterial inflow, cavernous smooth muscle relaxation and cavernous outflow occlusion. Histochemical results indicated nerve fibers positive for calcitonin-gene-related peptide within the cavernous bodies. A dose-dependent erectile response to calcitonin-gene-related peptide was observed at doses of 500 ng. to 25 micrograms. Systemic side effects were first observed at a dose of 25 micrograms in 2 of 7 patients. The combination of calcitonin-gene-related peptide and prostaglandin E1 was more effective in inducing a full erection than either prostaglandin E1 alone or the combination of papaverine and phentolamine. Pain was reported in 4% of the patients who received the combination of calcitonin-gene-related peptide and prostaglandin E1, whereas 42% of those who received prostaglandin E1 alone reported pain. Our results suggest that calcitonin-gene-related peptide may be a possible neurotransmitter for penile erection. A combination of calcitonin-gene-related peptide and prostaglandin E1 seems to be an effective alternative combination in the treatment of impotence.

Adult↗
PubMed1991

Effects of the nitric oxide synthase inhibitor NG-nitro-L-arginine on the erectile response to cavernous nerve stimulation in the rabbit.

Using a rabbit model, the involvement of the L-arginine/nitric oxide pathway in penile erection was investigated. The mean basal intracavernous pressure was 21 cm H2O. Cavernous nerve stimulation (4-8 V, 20-30 Hz) increased the pressure to approximately 130 cm H2O. This response was highly reproducible and usually associated with full penile erection. The pressure increase could be quantified in terms of: (1) the slope of the initial, ascending part of the pressure increase; (2) delta P, which was defined as the maximal pressure obtained by the stimulation minus the basal pressure before the stimulation; (3) T90, which was defined as the time to reach 90 per cent of delta P. Intrapenile administration of the L-arginine/nitric oxide synthesis inhibitor NG-nitro-L-arginine had no effect on systemic arterial blood pressure. However, NG-nitro-L-arginine (0.22 and 2.19 mg), administered via the same route, abolished the erectile response induced by cavernous nerve stimulation; T90 increased and slope and delta P decreased significantly. NG-nitro-D-arginine (2.19), on the other hand, had no inhibitory effect. L-arginine (21.07 mg), given either directly or after NG-nitro-L-arginine had no consistent effect on the functional response to cavernous nerve stimulation. The results suggest that pharmacologically induced effects on intracavernous pressure in the rabbit can be described quantitatively, and that this model may be useful to study the mechanisms controlling penile erection in vivo. The pronounced inhibitory action of NG-nitro-L-arginine demonstrates the important role of the arginine/nitric oxide pathway in mediating relaxation of penile smooth muscles necessary for erection.

Amino Acid Oxidoreductases↗
PubMed1991

Trends in future urodynamics: computer support-data base-digitized imaging.

The use of computers in urodynamics must be based preferably on the structure of the urodynamic investigation itself. This enables implementation of computerized systems in the urodynamic laboratory in the most natural way and provides transparency of urodynamic software for the investigators. Additionally, the algorithms of the urodynamic software then can provide for a urodynamic investigation following a logical path based on the patient's history and clinical data and (automatically interpreted) results from earlier steps in the urodynamics. As an extension of this structured logical reasoning, the computer use in urodynamics can be extended to include validation and decision rules, comprising measurement data and rules for interpretation and combination of history, clinical and measurement data. Conclusions will be presented then in the form of a preliminary differential diagnosis, including the odds for each of the possible diagnoses. These kinds of computerized interpretation systems will be validated by comparison with the classical clinical diagnoses and are generally known as expert systems. These systems rely on logical branching-as opposed to systems that are statistical in nature and use large data bases to classify individual data into known groups. Data bases will remain for the purpose of documentation, based on individual patients and comprising all patient data-comparable to the existing patient files in the hospital's archives. The computer files have to include also the original data from functional studies like urodynamics-and not just the abstracted conclusions-and from imaging techniques. Intelligent compression of data prevents the data bases from exploding. Digital imaging techniques combined with computerized urodynamic investigations open possibilities for dynamic analysis of morphologic data and combination thereof with urodynamic measurement data.

Databases, Factual↗
PubMed1991

Entering data into expert system for lower urinary tract pressure-flow studies.

This paper describes methods of entering data into an expert system used to study lower urinary tract pressure and flow. Data is usually entered into an expert system directly from the keyboard or on an online basis. We have developed a new method of offline data entry using a photoscanner. For this method, we developed versatile software to convert the graphic data read by a photoscanner to online data format. This software allows us to handle graphic data printed on paper in the same way as online data. The software is also designed to solve the problems caused by blurred lines or ink spots on printed charts. In other words, the software compensates for data reading errors caused by blurred or stained lines on printed charts. Because data can be entered through the photoscanner, the enormous volume of data already recorded in graphic forms can be used by the expert system. As a result, the diagnostic capability of the expert system is significantly improved.

Diagnosis, Computer-Assisted↗
PubMed1991

Human fetal hepatocytes respond to inflammatory mediators and excrete bile.

Under strict observation of the ethical guidelines of the 1975 Declaration of Helsinki Human Research Committee, primary hepatocyte cultures were prepared from second-trimester fetal liver specimens. We have shown for the first time that fetal hepatocytes have the capacity to produce an acute-phase response on treatment with inflammatory mediators. Addition of interleukin-6 to the cultures resulted in strong induction of C-reactive protein and alpha-1-antichymotrypsin expression, whereas albumin expression was repressed. In contrast to interleukin-6, transforming growth factor-beta did not induce C-reactive protein expression. However, as in adult hepatocytes, fetal cells responded to transforming growth factor-beta by reduced albumin synthesis. We were able to show by virtue of fluorescein excretion into sealed clefts that fetal hepatocytes have the functional capacity to form bile. Our findings indicate that second-trimester hepatocytes can be regarded as fairly mature liver cells.

Acetylcholine↗
PubMed1991

[Silicone-silver penis prosthesis (Jonas-Eska), long-term experiences. A critical assessment].

As an example of a semirigid/malleable penile prosthesis for the treatment of erectile dysfunction, the silicone-silver device is described. After a short introduction in which all types in current use are listed, the penile prosthesis itself and the implantation technique are described and the long-term results, which are good in around 92% of the cases, are presented. Importance is attached to the problems and complications and to the specification of surgical aids needed for successful implantation. In view of the alternative treatment options available, the use of alloplastics is now regarded as a last option in the treatment of erectile dysfunction; however, even in 1991 penile implants give the best results known so far.

Erectile Dysfunction↗
PubMed1991

[Diagnosis and therapy of renal echinococcosis].

About 60% of clinically diagnosed cases of echinococcosis are found in the liver. Echinococcal involvement of the kidney is extremely rare. Imaging techniques such as sonography and CAT scan disclose typical findings are obtained in most of the cases. In this paper the necessary diagnostic procedure and a organ-preserving surgical technique are described.

Adult↗
PubMed1990

Induction of an interleukin-1 receptor (IL-1R) on monocytic cells. Evidence that the receptor is not encoded by a T cell-type IL-1R mRNA.

Primary human monocytes and the human monocytic cell line THP-1 were induced to express receptors for interleukin-1 alpha (IL-1 alpha) and IL-1 beta. Treatment of primary monocytes with dexamethasone resulted in a 10-fold increase in receptor number over untreated cells, to approximately 2,000 receptors/cell. Treatment of THP-1 cells with phorbol ester followed by prostaglandin E2 and dexamethasone resulted in the expression of approximately 30,000 receptors/cell. Competitive binding assays on THP-1 cells showed that both IL-1 alpha and IL-1 beta bind to the same receptor. The monocyte IL-1R is significantly smaller (63 kDa) than the T cell IL-1R (80 kDa) and is immunologically distinct. However, induction of monocytes and monocytic cell lines leads to the appearance of an abundant mRNA of approximately 5,000 bases which hybridizes to a cDNA probe from the T cell-type IL-1R. Sequence data obtained from a cDNA clone of this mRNA indicate that the message is identical to the T cell IL-1R mRNA throughout the coding region. A smaller mRNA, also homologous to the T cell IL-1R mRNA, accumulated in induced THP-1 cells and has a shorter 3'-untranslated region than the larger. Data are presented which suggest that neither form of this message encodes the 63-kDa IL-1R, but rather that this protein is the product of a separate nonhomologous mRNA.

Cell Line↗
PubMed1990

[The modular image analysis computer for assessment of prognosis in testicular tumors].

Since 1981 a total of 107 patients with non-seminomatous germ cell tumors of the testis (NSGCT) in clinical stage I were assigned to a "wait and see" protocol. At a median follow-up of 40 months (4-100) thirty seven pts. (35%) relapsed with 84% of these within the first year. Employing the Hedley-technique out of 50 primary tumor-tissues available nuclear suspensions were obtained, staining according to the DNA-Feulgen-procedure and evaluated by the modular image analysis computer (MIAC, Leitz, FRG). In 67% hyperpentaploidy was found in the cases with progression while only 23% exhibited a greater than 5c-rate in the NED-group. With logistic regression achieving a p-value of 0.0296 hyperpentaploidy has to be considered a significant prognosticator in NSGCT/CS I.

Dysgerminoma↗