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Biomedical subjects

C G Stief

Publications and source records attributed to C G Stief.

At least 127 records · Page 7Linked to original sources
PubMed1993

Efficient pathway for early detection of prostate cancer concluded from a 5-year prospective study.

In a prospective study the statistical characteristics of digital rectal examination (DRE), transrectal ultrasound (TRUS), and serologic determination of prostate-specific antigen (PSA) were assessed in 1230 patients aged over 40 years. The sensitivity, specificity, and positive and negative predictive values were determined to be 80.3%, 69.7%, 58.9%, and 86.7%, respectively, for DRE; 76.5%, 62.3%, 52.3%, and 83.1%, respectively, for TRUS; and 87.9%, 49.6%, 48.5%, and 88.3%, respectively, for PSA (normal level, 4 ng/ml). The data clearly demonstrate the nonsuitability of each single measure for reliable early detection of prostatic carcinoma. Connection of the parameters in all possible combinations under various conditions demonstrated the superiority of the test "DRE and PSA > 4 ng/ml" over DRE as the "gold standard" and all other options. The use of this approach as the first-line raster of an algorithm (outlined herein) would allow the detection of prostatic malignancy with a specificity of 86.5% and a positive predictive value of 74.0%. Supplementing this screen with short-term controls in cases in which only one parameter is positive ("DRE or PSA > 4 ng/ml") might enable the detection of almost all patients with prostate cancer. TRUS did not provide any additional information.

Adult↗
PubMed1993

Calcitonin gene-related peptide: possibly neurotransmitter contributes to penile erection in monkeys.

The distribution of calcitonin gene-related peptide (CGRP) immunoreactivity in the cavernous tissue and the erectile response to intracavernous injection of CGRP was investigated in 7 monkeys. Intracavernous CGRP increased cavernous arterial flow and induced cavernous smooth muscle relaxation and venous outflow occlusion. Intracavernous injection of CGRP antibody did not significantly change the erectile response to cavernous nerve stimulation. Histologic staining for CGRP immunoreactivity showed nerve fiber-like staining within the cavernous arterial wall and the cavernous smooth muscles. These data suggest that CGRP may contribute to penile erection in monkeys.

Animals↗
PubMed1993

Predictive value of real-time RigiScan monitoring for the etiology of organogenic impotence.

We performed routine diagnostic evaluations in 160 consecutive patients from our impotence clinic. After the diagnostic studies were completed, the results of RigiScan* monitoring during visual sexual stimulation before and after intracavernous injection of vasoactive drugs were compared to the results of standardized pharmacological testing, single potential analysis of cavernous electrical activity and pharmacocavernosometry. The results suggest RigiScan monitoring to be a highly accurate method to evaluate and document objectively the erectile response after intracavernous injection of vasoactive drugs. Although pathological monitoring after intracavernous injection is significantly associated with pathological findings in the specific evaluation, the predictive value of RigiScan monitoring for specific organogenic etiologies is not satisfactory, since normal monitoring showed no convincing correlation to single potential analysis of cavernous electrical activity or cavernosometry.

Erectile Dysfunction↗
PubMed1993

Followup results of a combination of calcitonin gene-related peptide and prostaglandin E1 in the treatment of erectile dysfunction.

Recent human and animal studies have shown a possible role for calcitonin gene-related peptide in penile erection and a therapeutic benefit in combination with prostaglandin E1 for autoinjection therapy. The ethical committee approved calcitonin gene-related peptide-prostaglandin E1 combination for cases of nonresponse or cavernous fibrosis to papaverine-phentolamine. Since June 1990, 65 patients (59 nonresponders and 6 with fibrosis) were injected with 5 micrograms. calcitonin gene-related peptide plus 10 micrograms. prostaglandin E1. Of the 59 nonresponders to papaverine-phentolamine 31 and of the 6 patients with fibrosis 5 had full erectile response. Of these 36 patients 2 experienced pain during the pharmacologically induced erection. A total of 39 patients who had had at least 20 autoinjections of calcitonin gene-related peptide plus prostaglandin E1 was available for minimum followup. There were no side effects, such as pain (the 2 patients with pain mentioned previously were not included in the autoinjection therapy group), systemic side effects or (increased) fibrosis. Our results show that a combination of calcitonin gene-related peptide and prostaglandin E1 may be beneficial to the treatment of impotence in carefully selected patients.

Alprostadil↗
PubMed1993

Single potential analysis of cavernous electrical activity. Four years' experience in more than 500 patients with erectile dysfunction.

Since the recent introduction of cavernous electromyography by Gerstenberg and Wagner, a new too for the study of erectile dysfunction in man is available. The refinement of this method, single potential analysis of cavernous electrical activity (SPACE), offers a straightforward approach to the diagnosis of cavernous autonomic neuropathy and smooth muscle myopathy by minimal invasive means. SPACE was done in more than 500 consecutive patients with erectile dysfunction and in 85 normal control subjects. With increasing experience the methodology was refined with respect to the used hardware as well as cut-off frequencies. In normal control subjects, SPACE showed a reproducible regular activity with potentials of low frequency and electrical silence inbetween. The potentials were synchronous throughout the cavernous bodies. In patients with peripheral autonomic denervation, asynchronous potentials with higher frequencies and irregular shape were found. Normal and abnormal potentials were found in patients with upper spinal cord lesions. Recordings obtained with surface electrodes showed similar characteristics when compared with recordings obtained with needle electrodes. Recent studies show that SPACE provides independent information about the autonomic and myogenic intactness of the cavernous tissue. Currently, a computerized expert system and a graded classification for easier interpretation is being developed with first results. We conclude that cavernous electrical activity can be recorded. SPACE is a reproducible diagnostic tool for erectile dysfunction.

Action Potentials↗
PubMed1993

Single potential analysis of cavernous electrical activity (SPACE). Experiences, limitations and perspectives.

Cavernous electromyography was first introduced by Wagner and Gerstenberg in 1989. The authors developed a refined method of cavernous electromyography by means of single potential analysis in introduced this method into clinical Urology as a diagnostic procedure for the evaluation of patients presenting with erectile dysfunction. To date, our experience with single potential analysis of cavernous electrical activity (SPACE) includes more than 500 patients with erectile dysfunction of various etiologies and 92 normal control subjects. Several technical modifications and refinements have been adopted during the last 4 years. In normal control subjects, SPACE shows a regular pattern of activity with long phases of electrical silence at the usual amplification interrupted by synchronous low frequency, high amplitude potentials. In patients with disruption of the peripheral autonomic supply, typical asynchronous potentials with higher frequencies and irregular shape are observed. In complete spinal cord lesions, abnormal as well as normal electrical activity is found. In patients with a long history of insulin-dependent diabetes and presumably cavernous smooth muscle degeneration, SPACE recordings show irregular potentials with low amplitudes and slow depolarization speed. Synchronization of electrical activity is usually absent. Recent studies on patients with venous leakage show that SPACE provides independent clinical information about the cavernous smooth musculature. The recording of cavernous electrical activity is possible and reproductible. In the future, a new software for one-line date processing, storage and interpretation of SPACE signals will be available.

Action Potentials↗
PubMed1993

Intracavernous application of SIN-I in rabbit and man: functional and toxicological results.

The mode of action of the active metabolite SIN-I of the vasodilator prodrug molsidomine was studied in vitro and in vivo in corpus cavernosum of rabbit and man. SIN-I produces a dose-dependent relaxation of isolated human cavernous smooth muscle strips. In the rabbit, the intracavernous application of SIN-I increased the intracavernous pressure to a full erection (approximately 100 cm H2O). This response was highly reproductible. SIN-I was also injected intracavernously 6 times in five rabbits over 2 weeks; no inflammatory or fibrotic reactions were found on histology. SIN-I may be a reliable drug for the treatment of impotence without side-effects.

Animals↗
PubMed1993

[Results of surgical therapy for venous insufficiency as a cause of erectile disorders].

Since penile vein ligation is usually associated with a poor postoperative outcome, a study was undertaken to evaluate possible prognostic factors for this procedure. A total of 44 patients with erectile dysfunction underwent ligation of all dorsal penile veins and resection of the deep dorsal penile vein for venous impotence. A comprehensive study of all patients was made. All patients did not respond to pharmacotherapy and had a venous leak. With a minimum follow-up period of 6 months, patients were categorized as follows: full spontaneous erections, those patients responding to pharmacotherapy and those showing no improvement. Out of 44 patients, 13 had full spontaneous erections postoperatively, 5 now responded to pharmacotherapy and 26 showed no improvement. The maintenance flow was 89 +/- 50 ml/min in the group with spontaneous erections and 85 +/- 49 ml/min in those showing no improvement (P = 0.78). Out of the 20 patients with normal single potential analysis of cavernous electric activity (SPACE), 12 had full erections postoperatively, 4 showed no improvement and 4 responded to pharmacotherapy. Of the 24 patients with abnormal SPACE, 1 developed full erections, 1 now responds to pharmacotherapy and 22 showed no improvement. Our results indicate that SPACE seems to be an important prognostic factor for the postoperative outcome of penile vein ligations for venous impotence.

Adult↗
PubMed1992

Effects of cytokines on growth in vitro of primary human renal cell carcinoma.

In clinical trials different haematopoietic active cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) have been proven to alleviate myelosuppressive side effects of intensive chemotherapy in different non-urological malignancies. On the other hand, these cytokines can directly stimulate the proliferation of cells originating from some non-urological tumours. To clarify the impact of these cytokines on the proliferative behaviour of human renal cell carcinoma (RCC), 29 previously untreated RCC tumours were prepared for culturing in vitro using the cell cluster technique. The success rate for growth in vitro was 82.8% (24/29). The malignant renal cells were treated with different cytokines (GM-CSF, G-CSF and interleukin-3) in different dosages. Cell number and proliferation rates detected by immunostaining were used for treatment evaluation. A dosage-dependent stimulation of cell growth could not be observed compared to untreated cells. From the data presented in this study, proliferative stimulation of RCC by administering colony-stimulating factors in clinical trials cannot be assumed.

Carcinoma, Renal Cell↗
PubMed1992

The influence of anterior root stimulation (S2) in deafferented spinal cord injury men on cavernous electrical activity.

Registration of cavernous electrical activity (single potential analysis of cavernous electrical activity) was recently suggested for the diagnosis of autonomic cavernous dysfunction. For validation of this method the effect of sacral neurostimulation on cavernous electrical activity was examined. In 3 male patients with a complete spinal cord lesion (T3, T4 and T12, respectively), deafferentation was done at the S2 to S5 levels. Around the anterior roots of S2 to S5 electrodes for neurostimulation were placed. Cavernous electrical activity was recorded with an intracavernous needle electrode and with surface electrodes in the flaccid as well as in the erect states induced by neurostimulation (at 7, 8, 12, 18, 20, 30 and 45 Hz., 30 v. and 0.4 msec). In all patients similar potentials compared to the normal values, as well as additional pathological potentials were recorded during flaccidity. During neurostimulation all patients achieved full erection with no or markedly decreased cavernous electrical activity to frequencies of 12, 18, 20 and 30 Hz., while to 7, 8 and, more pronounced, 45 Hz. only partial erection with ongoing cavernous electrical activity was found. Our study strongly suggests that cavernous electrical activity and, subsequently, the cavernous smooth muscle tone are dependent on autonomic input. This finding supports the hypothesis that single potential analysis of cavernous electrical activity may be valid in the diagnosis of cavernous autonomic dysfunction. Furthermore, our results suggest a possible role for single potential analysis of cavernous electrical activity in the fine tuning of erection inducing neurostimulators.

Adult↗
PubMed1992

Effect of intracavernous simultaneous injection of acetylcholine and vasoactive intestinal polypeptide on canine penile erection.

We investigated the effects of intracavernous injection of a combination of acetylcholine (ACh) and vasoactive intestinal polypeptide (VIP) on the erectile response in eleven adult male dogs. The minimum dose of ACh which increased the intracavernous pressure in eight dogs varied from 0.2 to 40 micrograms, and the minimum dose of VIP varied from 0.2 to 5 micrograms. When the minimum doses of ACh and VIP were injected simultaneously, a strong increase of intracavernous pressure (the mean increase was 102 cm. H2O from the baseline level) and a sustained erection (mean 5 min.) were observed in all eight dogs. The effect of simultaneous injection of both drugs was not additive but synergistic. Pretreatment with VIP-antibody and atropine intracavernously suppressed the erectile response induced by cavernous nerve stimulation. VIP may increase the affinity of muscarinic receptors for ACh in canine corpus cavernosum because pretreatment with atropine alone before the simultaneous injection of ACh and VIP completely abolished the effect of the combination. We conclude that ACh and VIP may play a cooperative role in canine penile erection.

Acetylcholine↗
PubMed1992

A new therapeutic concept for long-lasting iatrogenic priapism: a case report.

In a therapeutic attempt on an 18-year-old patient with iatrogenic priapism lasting for more than 2 weeks after internal urethrotomy, intracavernous lysis was commenced with 80,000 IU streptokinase per hour. Following a dosage of 300,000 IU streptokinase the lysis was stopped because of severe bleeding from the urethrotomy scar. At 4 weeks after the patient was discharged from the hospital he reported normal erections and intercourse, while single potential analysis of cavernous electrical activity and ultrasound returned to normal. Provided there are no contraindications, intracavernous lysis seems to be an effective treatment for long-lasting priapism induced by intracavernous thrombosis.

Adolescent↗
PubMed1992

Preliminary results with the nitric oxide donor linsidomine chlorhydrate in the treatment of human erectile dysfunction.

Recent experimental studies showed an important role of endothelium derived relaxing factor for cavernous smooth muscle relaxation. Since nitric oxide seems to account for the biological actions of endothelium derived relaxing factor, a study was done to examine a possible role of the nitric oxide donor linsidomine chlorhydrate (SIN-1) in the treatment of erectile dysfunction. To determine a therapeutically useful dose 0.1, 0.2, 0.5 and 1 mg. SIN-1 were injected intracavernously in patients with erectile dysfunction. Each dose was given to 2 patients. Then, 63 patients received 1 mg. SIN-1, including 7 who had prolonged erections to minimal doses of papaverine plus phentolamine and 4 who did not respond with a full erection to other pharmacological agents. Intracavernous injection of SIN-1 induced a dose-dependent erectile response by increasing the arterial inflow and relaxing cavernous smooth muscles. Of the patients 29 had a full, 21 an almost full and 13 a moderate erection to 1 mg. SIN-1. There were no systemic or local side effects. In the patients with prolonged erections to papaverine plus phentolamine the mean duration of a full erectile response to SIN-1 was 57 minutes. Compared to the responses to a papaverine (15 mg./ml.) and phentolamine (0.5 mg./ml.) mixture, the erection induced by SIN-1 was superior in 10, comparable in 47 and inferior in 6 patients. Our data suggest a possible role for SIN-1 in the treatment of erectile dysfunction. Possible advantages may be that erection is induced by a mechanism similar to that occurring physiologically, a decreased risk of inducing prolonged erections and low therapy costs.

Blood Flow Velocity↗
PubMed1992

Transcutaneous registration of cavernous smooth muscle electrical activity: noninvasive diagnosis of neurogenic autonomic impotence.

Registration of cavernous electrical activity was shown to be a possible method for the evaluation of cavernous autonomic innervation. Recent studies in patients with normal erectile function showed that cavernous electrical activity is synchronous throughout the entire cavernous bodies. Therefore, we examined the feasibility of transcutaneous registration of cavernous electrical activity in 8 normal and 62 impotent patients. In the sitting patient cavernous electrical activity was recorded with a 2-channel electrophysiological unit. Recording was done with a coaxial needle electrode in the proximal left cavernous body and with surface electrodes bilaterally on the penile shaft. In 7 of 8 normal patients swelling of the penile shaft after circumcision resulted in a dramatically decreased amplitude of the potentials. In 41 of 62 impotent patients recordings were similar. In 10 of 62 patients no recording or markedly decreased amplitudes were noted with the surface electrodes and in these patients a small penis or penile retraction with consecutive electrode displacement was found. Careful repositioning of the surface electrodes with the patient in the supine position resulted in similar recordings in 9 (inconsistently in 4). In 11 of the 62 patients more information was obtained with the surface than with the needle electrode. Our results show that recording of cavernous electrical activity can be done in a completely noninvasive manner using surface electrodes with similar or even better information obtained than with needle electrodes.

Action Potentials↗
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↗