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H Danuser

Publications and source records attributed to H Danuser.

33 records · Page 2Linked to original sources
PubMed1997

Extrinsic innervation of the cat prostate gland: a combined tracing and immunohistochemical study.

PURPOSE: The purpose of the present study was to determine the peripheral neural pathways, spinal distribution, sizes, and peptide transmitter content of primary afferent and autonomic efferent neurons that innervate the prostate gland. METHODS: Retrograde transport of the fluorescent dye "fast blue" (injected into the prostate gland) was combined with neurotransmitter immunohistochemistry. Lesions of the pelvic and pudendal nerve were used to determine the peripheral neural pathways. RESULTS: The majority of the afferent innervation arose from the sacral dorsal root ganglia (DRG) and was equally comprised of small, substance P- and calcitonin gene-related peptide-immunoreactive (IR) neurons and large, non-IR neurons. The majority (70%) of the afferent axons traversed the pelvic nerve with the remainder traversing the pudendal nerve. Fewer afferent neurons were located in lumbar DRG; nearly all of these were small, peptidergic neurons. Efferent autonomic neurons were located in the inferior mesenteric ganglia (IMG), sympathetic chain ganglia (SCG), and pelvic plexus ganglia (PPG). Nearly all efferent neurons in the IMG and SCG, but only 2/3 of the PPG neurons, contained dopamine-beta-hydroxylase. Substantial neuropeptide Y innervation was derived from the SCG but not the IMG or PPG. CONCLUSIONS: First, clinical reports suggested that sensory innervation of the prostate would be purely nociceptive in nature (implied by small, peptide-IR neurons). However, the present study suggests that there may also be a substantial, presumably non-nociceptive, afferent innervation (implied by findings of large, non-IR neurons). Second, 3 sources of autonomic efferent innervation exist, each being different in the distribution of transmitter phenotypes. Understanding the physiological role of putative non-nociceptive primary afferent neurons, and the differential roles of the various autonomic neurons, is likely to be important in developing therapies for the treatment of prostatic diseases, such as benign prostatic hyperplasia and prostatodynia.

Amidines↗
PubMed1997

[Long-term urodynamic and clinical follow-up in 70 patients with ileal bladder replacement combined with an antireflux mechanism or an afferent tubular segment].

OBJECTIVES: A low-pressure ileal bladder replacement does not have any coordinated contraction during micturition, which is why we have evaluated various antireflux mechanisms in the context of a randomized prospective study. MATERIAL AND METHODS: 70 patients undergoing low-pressure ileal bladder replacement were randomized into 2 groups. An antireflux mechanism was performed in 35 patients and an afferent tubular segment was performed in the other 35 patients. RESULTS: After a median follow-up of 57 and 45 months respectively, the functional capacity of the reservoir, incidence of urinary tract infections, urinary continence, voiding havits, and serum urea and creatinine were similar in the two groups. 11/67 (16.5%) evaluable ureteropelvic units with an antireflux mechanism and 2/69 (3%) units with an afferent tubular segment developed major dilatation due to stenosis of the antireflux mechanism or the ureteroileal anastomosis (Fisher's exact test, p < 0.009). No radiological reflux could be demonstrated during micturition in either group. A simultaneous increase of intravesical, intraabdominal and intrapelvic pressure was observed during a Valsalva manoeuvre. CONCLUSION: Protection of the upper urinary tract by an ileal afferent tubular segment has yet to be confirmed in a larger series of patients with a longer follow-up. Our results show that prevention of reflux is less important in the case of orthotopic low-pressure ileal bladder replacement. Consequently, creation of an antireflux mechanism, associated with a high complication rate, is probably not justified.

Adult↗
PubMed1996

Summary of 10 years' experience with an ileal low-pressure bladder substitute combined with an afferent tubular isoperistaltic segment.

We report on 10 years of experience with an ileal low-pressure bladder substitute combined with an afferent tubular segment following cystectomy in 100 consecutive men. The median follow-up period was 30 months (range 3-108 months), with a 2.5-year minimum in survivors. A total of 42 patients died, 33 of these dying of bladder cancer. The early complication rate was 11%, including 2 deaths due to postoperative sepsis. In all, 14 patients required reoperation for late complications. The reservoir's median functional capacity increased to 500 ml at 12 months and was paralleled by improving continence: 92% by day (after 1 year) and 80% by night (after 2 years). Four ureteric strictures occurred. No coordinated, isolated pressure rise developed in the reservoir during voiding, which was accomplished by pelvic floor relaxation with abdominal straining, if necessary. Raised intraabdominal pressure acted equally on the reservoir and ureters, preventing reflux during voiding. This technique is straightforward, allows radical cancer surgery, and protects the upper tract. The favorable functional results are comparable with those achieved by similar techniques, but meticulous follow-up is essential.

Adult↗
PubMed1996

No evidence of osteopenia 5 to 8 years after ileal orthotopic bladder substitution.

PURPOSE: The use of bowel segments as bladder substitutes may result in chronic, impaired vitamin D and calcium metabolism, and ultimately in bone demineralization. MATERIALS AND METHODS: Bone metabolism was examined in 14 patients who lived for 5 to 8 years with an ileal low pressure bladder substitute after radical cystectomy for bladder cancer. Bone mineral density was measured using dual energy x-ray absorptiometry of the total skeleton, lumbar spine, femoral neck, and tibial epiphysis and diaphysis. Laboratory studies included serum levels of 1,25-dihydroxyvitamin D, 25-hydroxyvitamin D, intact parathyroid hormone, plasma alkaline phosphatase, electrolytes, creatinine and blood gas analysis. RESULTS: Bone mineral density was normal in all patients. There was no evidence of deficient vitamin D stores. There was a tendency toward slightly elevated serum creatinine values in patients with preexisting impaired renal function, including 1 who also had slight acidosis. No patient had hyperchloremia. CONCLUSIONS: We found no evidence of osteomalacia, osteoporosis or significant metabolic acidosis in 14 patients with an ileal bladder substitute for 5 to 8 years. However, it is not known whether the absence of osteopenia would also apply to patients with poor renal function, to those not followed meticulously and, thus, at risk for major long-term functional or metabolic disturbances from the ileal bladder substitute or to patients with orthotopic bladder substitutes made from longer or other bowel segments than we used.

Acidosis↗
PubMed1996

Spinal 5-HT2 receptor-mediated facilitation of pudendal nerve reflexes in the anaesthetized cat.

1. 5-Hydroxytryptamine (5-HT) is intimately associated with central sympathetic and somatic control of the lower urinary tract. The sympathetic and somatic innervation of the lower urinary tract is conveyed through efferent axons of the hypogastric and pudendal nerves, respectively. 2. The present study examined the effects of 2,5-dimethoxy-4-iodophenylisopropylamine (DOI), a 5-HT2 receptor subtype-selective agonist, on evoked potentials recorded from the central ends of the hypogastric and pudendal nerves in response to electrical stimulation of afferent fibres in the pelvic and pudendal nerves, respectively. Various spinalization paradigms were employed to localize the site of action. All cats were pretreated with xylamidine (1 mg kg-1), a peripherally-restricted 5-HT2 receptor antagonist. 3. In acute spinal cats, DOI (0.01-3 mg kg-1, i.v.) reliably produced dose-dependent increases in the pudendal nerve reflex (to 228 +/- 31% of control). These increases were reversed by the 5-HT2 receptor-selective antagonist, LY53857 (0.3-3 mg kg-1, i.v.). On the other hand, in spinally-intact cats, DOI produced no significant changes in the pudendal reflex. However, within minutes of spinalization of DOI-pretreated cats, a marked increase (to 221 +/- 16% of control) in the pudendal reflex was observed which could be reversed by LY53857. No significant effects were observed on hypogastric reflexes in either acute spinal or spinally-intact cats following DOI administration. No effects were seen in either spinally-intact or acute spinal animals when LY53857 was administered as the initial drug. 4. These results indicate that activation of spinal 5-HT2 receptors facilitates pudendal reflexes. In spinally-intact cats, it is hypothesized that DOI activates supraspinal pathways that mediate inhibition of the pudendal reflexes and counteracts the facilitatory effects of spinal 5-HT2 receptor activation.

Amphetamines↗
PubMed1996

Antireflux nipples or afferent tubular segments in 70 patients with ileal low pressure bladder substitutes: long-term results of a prospective randomized trial.

PURPOSE: Intestinal low pressure orthotopic bladder substitutes have no major coordinated contractions during micturition. Therefore, the importance and type of reflux prevention were assessed in a prospective randomized study. MATERIALS AND METHODS: A total of 70 patients with an ileal low pressure bladder substitute was randomized to receive a nipple valve or an isoperistaltic afferent ileal tubular segment for reflux prevention. RESULTS: After median observation times of 57 and 45 months, respectively, the results regarding functional reservoir capacity, incidence of infected urine, urinary continence, voiding habits and serum electrolytes, urea and creatinine were similar in both groups. Severe upper tract dilatation due to ureteroileal or nipple stenosis occurred in 9 of 67 evaluable reno-ureteral units (13.5%) in patients with antireflux nipples and in 2 of 69 (3%) in patients with an afferent tubular segment. This difference in favor of the latter cases is significant (Fisher's exact test p < 0.03). Video urodynamics did not show reflux of contrast medium during voiding in either group. A simultaneous intravesical, intra-abdominal and intrapelvic pressure increase was noted during the Valsalva maneuver. CONCLUSIONS: While long-term upper tract preservation by an afferent tubular ileal segment must be confirmed in larger patient series with longer followup, our results indicate that reflux prevention in patients with orthotopic low pressure bladder substitutes is not a major concern and does not justify the use of antireflux mechanisms with a high complication rate.

Adult↗
PubMed1995

Pharmacological analysis of the noradrenergic control of central sympathetic and somatic reflexes controlling the lower urinary tract in the anesthetized cat.

Norepinephrine (NE)-containing terminals densely innervate sympathetic preganglionic neurons in the intermediolateral nucleus and somatic motor neurons in Onuf's nucleus that project through the hypogastric and pudendal nerves, respectively, to innervate the lower urinary tract. In the present study, we pharmacologically analyzed the role of noradrenergic systems on the sympathetic and somatic pathways to the lower urinary tract and asked: 1) Are alpha-1, alpha-2, or beta-adrenergic receptors tonically active along sympathetic and/or somatic reflex pathways? And 2) what is the net effect of increasing the extracellular levels of NE by administration of a NE reuptake inhibitor? To address these questions, we recorded evoked potentials from the central ends of the hypogastric and pudendal nerves in response to electrical stimulation of the pelvic and pudendal nerves in chloralose-anesthetized cats, and the effects of prazosin (1-300 micrograms/kg i.v.), an alpha-1-adrenergic receptor antagonist; idazoxan (1-300 micrograms/kg i.v.), an alpha-2-adrenergic receptor antagonist; propranolol (1 mg/kg i.v.), a beta-adrenergic receptor antagonist; and tomoxetine (0.003-3 mg/kg i.v.), a selective NE reuptake inhibitor, were examined. The results indicate that facilitatory alpha-1-adrenergic receptors are tonically active along both sympathetic and somatic reflex pathways, whereas inhibitory alpha-2-adrenergic receptors are not tonically active. The net effect of acute inhibition of NE reuptake along sympathetic reflex pathways is increased activation of inhibitory alpha-2-adrenergic receptors. Along somatic reflex pathways, increased activation of both facilitatory alpha-1- and inhibitory alpha-2-adrenergic receptors were recorded after acute NE reuptake inhibition. No role for central beta-adrenergic receptors was noted.

Anesthesia↗
PubMed1995

Experience in 100 patients with an ileal low pressure bladder substitute combined with an afferent tubular isoperistaltic segment.

Between April 1985 and April 1993, 100 consecutive men underwent lower urinary tract reconstruction after cystectomy. An ileal low pressure reservoir using the Goodwin cup-patch principle was combined with an afferent ileal tubular segment. The early complication rate was 11%, including 2 postoperative deaths due to septicemia. After a median followup of 27 months (range 3 to 96) 14 patients required surgery for late complications (intestinal obstruction, urethral stricture or tumor recurrence, hernia or ureteral stenosis). A total of 32 patients died of metastatic bladder cancer and 7 died of other causes. The functional capacity of the bladder substitute was increased to the desired 450 to 500 ml. after 3 to 12 months, which was paralleled by improving urinary continence. After 1 year 92% of the patients were continent by day and after 2 years 80% were continent at night. Upper tract surveillance with excretory urography, renal ultrasound and serum creatinine estimation has shown 4 left ureteral strictures but not significant upper tract deterioration or ureteral recurrence. Significant reflux was not observed during video urodynamics unless the reservoir was overfilled. During voiding, by outlet relaxation and straining if necessary, the intra-abdominal pressure increase with straining acted equally on the reservoir and ureters. Therefore, unlike voiding with a normal bladder, no isolated intravesical pressure increase occurred and, thus, there was no reflux from the reservoir. The combination of an ileal low pressure reservoir with an afferent isoperistaltic ileal segment and an open end-to-side ureteroileal anastomosis allows for radical cancer surgery with resection of the ureters where they cross the iliac vessels and minimizes the risk of ureteral stenosis. The unidirectional peristalsis of the ureters and the afferent tubular ileal segment seem to protect the upper urinary tract sufficiently. The surgical technique is straightforward and allows for later conversion to an ileal conduit if necessary. The functional results of the bladder substitute are comparable to other similar reservoir techniques, provided that the patients are carefully selected, well rehabilitated and meticulously followed.

Acidosis↗
PubMed1995

Inhibition of central sympathetic and somatic outflow to the lower urinary tract of the cat by the alpha 1 adrenergic receptor antagonist prazosin.

Selective alpha 1 adrenergic receptor antagonists are used to reduce the dynamic component of urethral obstruction in patients with benign prostatic hyperplasia. Their effectiveness is presumed to result from blockade of alpha 1 adrenergic receptors within the prostatic smooth muscle. However, a reduction in central sympathetic tone to the prostate might also contribute to their effectiveness. The present experiments examined the effects of the selective alpha 1 adrenergic receptor antagonist prazosin on sympathetic activity recorded from the hypogastric nerve in chloralose-anesthetized cats. For comparison, the effects of prazosin were also examined on somatic activity recorded from the pudendal nerve. When the urinary bladder was empty, prazosin reduced spontaneous activity recorded from the hypogastric nerve (to 65% of control) and reduced evoked reflex activity recorded from the hypogastric nerve (to 44% of control) and the pudendal nerve (to 48% of control). Interestingly, when the urinary bladder was filled, the inhibitory effects of prazosin on the pelvic to hypogastric reflex were overcome. These experiments indicate that central noradrenergic neurons mediate a tonic facilitation of sympathetic and somatic activity to pelvic viscera via activation of alpha 1 adrenergic receptors. Thus, alpha 1 adrenergic receptor antagonists may reduce the dynamic component of urethral outlet obstruction in patients with benign prostatic hyperplasia through dual mechanisms: first, through a blockade of alpha 1 adrenergic receptors on the prostatic smooth muscle itself and, second, by reducing the activity of the sympathetic neurons that innervate the prostate. Additional therapeutic relief may be provided through reduction of somatic neural activity to the external urethral sphincter, which might also reduce outlet resistance and improve flow.

Action Potentials↗
PubMed1993

[Partial kidney resection in renal cell carcinoma].

In 18 patients with renal cell carcinoma in anatomical or functional single kidneys, with limited renal function or bilateral tumors, partial renal resection was absolutely indicated to preserve renal function. In 17 patients with small peripheral tumors and intact contralateral kidney, partial renal resection was performed electively. One patient of each group died during postoperative care. During follow-up, 4 patients with absolute indication for partial renal resection showed progression of the disease. Three developed distant metastases, and in one patient local relapse with infiltration of the inferior cava vein occurred. These 4 patients had had a bilateral synchronous or asynchronous stage pT2 or pT3 renal cell carcinoma and died from the neoplasm within 10-36 months postoperatively. 13 of 18 patients with absolute indication remained tumorfree during a median follow-up period of 57 months. Partial renal resection saved 15 of these 17 patients from dialysis. Sixteen of 17 patients in whom partial renal resection was performed electively remained tumorfree during a median follow-up period of 28 months. The results suggest that, given an absolute indication to prevent dialysis, partial renal resection should be performed whenever technically possible. In patients with small peripherally located tumors and intact contralateral kidney, partial renal resection as an elective procedure must be considered a genuine alternative to radical nephrectomy.

Adult↗
PubMed1993

[Urological emergencies].

Every general practitioner has to deal with urologic emergencies. The most frequent illnesses are urinary retention, acute scrotum, priapism, macrohematuria, nephritic colic, obstructive pyelonephritis and pyonephrosis. Whereas urinary retention, as well as acute ureteric stone colic must generally be treated by the practitioner, the urologist must often be consulted in case of an acute scrotum or for priapism. Testicular torsion is one situation, where surgical treatment needs to be performed within 6 hours. Of utmost importance is his timely assistance with the obstructive pyelonephritis and pyonephrosis. These are initially often not recognized, especially because the first ultrasound examination of the intrarenal pyelone may not show a dilatation of the collecting system despite obstruction. If the adequate treatment with drainage and antibiotics is applied too late, this can result in serious and potentially lethal consequences.

Adult↗
PubMed1993

Extracorporeal shock wave lithotripsy in situ or after push-up for upper ureteral calculi: a prospective randomized trial.

A total of 110 patients with upper ureteral calculi was admitted to a prospective trial and randomly allocated to 2 groups: 1 group treated with in situ extracorporeal shock wave lithotripsy (ESWL) and 1 group treated with ureteral manipulation before ESWL. All patients had solitary upper ureteral calculi without urinary infection. The stones had to be smaller than 1 cm. and located more than 2 cm. lateral to the spine. ESWL was performed with the Dornier HM3 lithotriptor. One patient in the in situ ESWL group had to be treated twice because disintegration of the stone was insufficient after the initial treatment session. All other patients underwent only 1 treatment session. Because 16 patients were lost to followup, 94 were evaluable for the analysis of immediate and long-term results. For disintegration of the stones in situ ESWL needed significantly more shock waves (1,844 +/- 639 versus 1,297 +/- 473, p < 0.001) and a higher voltage (19.5 +/- 1.4 versus 18.7 +/- 0.9 kv., p < 0.001). There were no severe complications in either treatment group. At 3 months 44 of 46 patients (96%) after in situ ESWL and 45 of 48 (94%) after ureteral manipulation before ESWL were free of stones. In view of these results it is suggested that uncomplicated upper ureteral calculi (as defined previously) should be treated first with in situ ESWL, thus, avoiding an invasive procedure.

Adult↗
PubMed1989

[Abdominal tuberculosis and open lung tuberculosis caused by mycobacterium bovis].

Abdominal tuberculosis is a rare disease in Western countries and remains difficult to diagnose. The most frequent symptoms are abdominal pain, weight loss, fever, vomiting, constipation and/or diarrhea. Clinical findings include abdominal tenderness, a palpable mass (often in the right fossa due to ileocecal infection), paleness, cachexia and ascites. Suggested radiological investigations include plain abdominal film, upper GI-series and barium enema. Chest X-rays often show signs of either active or inactive tuberculosis. Sputum and gastric juice should be cultured. Coloscopy serves to sample specimens for histology and bacteriology and may help to confirm the diagnosis, which is, however, not ruled out by negative findings. The same holds good for peritoneal biopsy and laparoscopy. Bowel perforation and ileus are frequent complications and always require surgery, whereas uncomplicated cases can be treated by drugs only.

Adolescent↗
PubMed1989

[Buschke-Löwenstein tumor].

The rare disease entity of Buschke-Löwenstein tumor, a giant condyloma, is discussed with reference to a case history. The clinical picture is quite typical, whereas the histological differentiation from carcinoma can be difficult. The tumor exterts a local destructive effect by way of growth penetrating in to the deep tissue. Malignant transformation has been known to occur. These aspects have to be considered in therapy.

Aged↗