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S Meretyk

Publications and source records attributed to S Meretyk.

At least 19 recordsLinked to original sources
PubMed1992

Alpha 1-adrenoceptor properties of terazosin HCl and its enantiomers in the human prostate and canine brain.

The objective of the present study was to characterize the alpha 1-adrenoceptor binding properties of terazosin and its enantiomers in human prostate and canine brain. Human prostate adenomas were obtained from 7 males undergoing prostatectomy for symptomatic BPH and canine cerebral cortices were obtained from 6 male beagles. Competitive displacement experiments were carried out on these tissue homogenates in the presence of a constant concentration ([180 pM]) of 125I-Heat and varying concentrations of unlabelled terazosin and its enantiomers. The Ki of terazosin and its enantiomers were determined from these binding studies. The mean Ki of rac-terazosin, R(+)-terazosin, and S(-)-terazosin in human prostate was 3.6 nM, 3.8 nM, and 2.8 nM, respectively. The differences between these mean Ki values were not statistically significant. The mean Ki of rac-terazosin, R(+)-terazosin, and S(-)-terazosin in canine brain were 6.7 nM, 8.4 nM, and 5.6 nM, respectively. The differences between these mean Ki values were not significantly different. The mean Ki of terazosin and its enantiomers were consistently lower in the human prostate compared to canine brain (P less than 0.05). The present study does not provide any evidence suggesting differential effects of terazosin enantiomers on the human prostate. The twofold difference between the Ki values in the prostate and brain suggests that different subtypes of the alpha 1-receptor might be present in these tissues.

Adrenergic alpha-Antagonists↗
PubMed1992

Extracorporeal shock-wave lithotripsy (ESWL) monotherapy for stones in lower ureter.

Extracorporeal shock-wave lithotripsy (ESWL) has been accepted as the method of choice for most upper urinary tract calculi. However, in cases of stones in the lower ureter, ureteroscopic procedures have generally been preferred. Using the Dornier HM3 lithotriptor with modifications in the patient's position, we were able to successfully treat 155 unselected cases of lower ureteral calculi. The average stone size was 9.6 mm (range 5-23 mm). One hundred forty-three patients had stones located below the lower margin of the sacroiliac joint. These patients were placed in a supine position. The stones were visualized radiologically without use of a ureteral catheter in 78 percent of the patients; in 22 percent a ureteral catheter was inserted prior to ESWL to aid in stone localization. In 145 patients (94%) treatment was completed in one session; 10 patients (6%) required two sessions. Of the patients, 38 percent were free of stones one day after ESWL; 97 percent became stone free within three months, and only 3 patients required endoscopic manipulation, after ESWL. Twelve patients had stones in the midureter overlying the sacroileum. They were placed in the prone position, and the calculi were visualized with the aid of a ureteral catheter. All these patients became free of stones one month after treatment. There were no significant treatment-related complications except for bacteremia in 1 case. In view of the remarkable efficacy, negligible complication rate, and shorter hospital stay as compared to ureteroscopic stone manipulations, we recommend high energy ESWL as the primary monotherapy of mid and lower ureteral stones.

Adolescent↗
PubMed1992

Endopyelotomy: comparison of ureteroscopic retrograde and antegrade percutaneous techniques.

To date 2 approaches have been developed for performing endopyelotomy, that is the antegrade and retrograde approaches. Experience with antegrade transnephrostomy endopyelotomy is quite large and the results have been excellent. However, the need for percutaneous nephrostomy and prolonged hospitalization have been 2 drawbacks to this approach. In contrast, experience with retrograde transureteral endopyelotomy is scant. However, a ureteroscopic approach is attractive from the standpoint of eliminating the need for a large nephrostomy tube and because of the possibility of performing this procedure on an outpatient basis or during a short hospital stay. We report our experience with antegrade and retrograde endopyelotomy in 41 patients. The hospital stay (3.4 versus 4.0 days), nephrostomy tube size (8F to 10F versus 20F to 22F) and nephrostomy tube duration (2.9 versus 3.8 days) were all less with the retrograde approach. The initial success rate was similar between the 2 methods: 79% (retrograde) versus 78% (antegrade). However, the analgesic requirements (5.3 versus 3.5 doses) and the occurrence of significant complications (that is late ureteral stricture in 20%) were greater with the ureteroscopic approach. With the methods currently available, we believe that antegrade endopyelotomy is the preferred approach for endopyelotomy.

Adult↗
PubMed1992

Binding and functional properties of alpha 1 adrenoceptors and area density of smooth muscle in the canine prostate.

The present study was designed to compare the area density of smooth muscle, and the binding and functional properties of alpha 1 adrenoceptors in 8 different regions of the canine prostate. The area density of smooth muscle, alpha 1 adrenoceptor density, and contractile response to phenylephrine were investigated using immunoenzymatic staining with color assisted computer image analysis, radioligand receptor binding, and isometric tension studies, respectively. The equilibrium dissociation constants (Kd) for 125I-Heat binding and the alpha 1 adrenoceptor densities (Bmax) in the prostatic regions ranged between 138-230 pM and 0.32-0.52 fmol/wet wt., respectively. The maximal tension generated in the presence of phenylephrine (phenylephrine Emax) and phenylephrine EC50s ranged between 0.043-0.129 gm. force/mm.2 CSA and 4.0-11.0 microM, respectively. The differences between Kd, Bmax, Emax, and EC50 were not significantly different between the different regions of the prostate. The percent area density of smooth muscle ranged between 10.6-24.4%. A direct relationship was not observed between alpha 1 adrenoceptor density and phenylephrine Emax, or alpha 1 adrenoceptor density and percent area density of smooth muscle. A direct relationship was observed between the phenylephrine Emax and percent area density of smooth muscle (p = 0.003; r = 0.90). The phenylephrine Emax and percent area density of smooth muscle was threefold and 1.6-fold greater in the peripheral prostate relative to the central prostate, respectively. The morphometrical and isometric tension studies provides evidence that the canine prostate is a heterogeneous gland.

Animals↗
PubMed1992

Caveat emptor: caliceal stones and the missing calix.

The failure of a stone-containing calix to visualize on an imaging study (that is a missing calix) is often the initial and only sign of an associated pyocalix, since the patient may present without fever and with sterile urine. Extracorporeal shock wave lithotripsy (ESWL*) in these patients may lead to life-threatening systemic sepsis. Therefore, the treatment of choice for the stone-laden missing calix is percutaneous drainage of the affected calix followed by percutaneous stone removal and, when necessary, an endoinfundibulotomy to reestablish communication between the obstructed calix and the renal pelvis.

Adult↗
PubMed1992

Endoureterotomy for treatment of ureteral strictures.

Advances in endosurgical technology have provided the urological surgeon with an alternative to open surgery for the treatment of ureteral strictures. We report the use of an endoscopic intraureteral incision (endoureterotomy) followed by balloon calibration to treat benign ureteral strictures in 13 patients. With an average subjective and objective followup among successful endoureterotomies of 20 months (all cases 12 months or greater), the overall success rate for this procedure is 62%. Of these patients 5 also received triamcinolone injections into the stricture bed following incision and dilation. This method appeared to influence favorably subsequent ureteral patency. The only operative complication was a urinoma, which resolved without intervention. Endoureterotomy appears to be a safe and reasonably effective modality for the treatment of ureteral stricture disease.

Adult↗
PubMed1992

The safety, efficacy and compliance of terazosin therapy for benign prostatic hyperplasia.

The primary objective of the present interim analysis of an open label study initiated in December 1988 is to provide further insight into the long-term safety, efficacy and compliance of terazosin, a long-acting selective alpha 1-blocker, for the treatment of symptomatic benign prostatic hyperplasia (BPH). A total of 45 normotensive patients with symptomatic BPH was enrolled into this study. The dose of terazosin was titrated to 5 mg. during a 1-month period provided adverse reactions and orthostatic hypotension were not observed. The subjects were maintained on 5 mg. terazosin throughout the 24-month followup. The peak and mean urinary flow rates, obstructive and irritative Boyarsky symptom scores, and systolic and diastolic blood pressures were evaluated at 2, 6, 12, 18 and 24 months after initiation of therapy. Of the 45 subjects 21 (47%) exhibited a durable clinical response with no significant adverse events during the 24-month followup. The obstructive and irritative symptom scores decreased by 63% and 35%, respectively, after 2 months of terazosin therapy. These improvements in obstructive and irritative symptom scores were maintained throughout the 2-year followup. The peak and mean urinary flow rates improved by 42% and 48%, respectively, after 2 months of terazosin therapy. The changes in mean urinary flow rate increased, whereas the changes in peak urinary flow rate decreased during followup. Of the patients 6 (13%) were withdrawn from the study due to an adverse event. Our study demonstrates the safety, efficacy and compliance of terazosin therapy for BPH during a 2-year followup.

Adrenergic alpha-Antagonists↗
PubMed1992

Retroperitoneoscopy: foreign body retrieval.

Retroperitoneoscopy is a rarely indicated procedure for the urological surgeon. However, it can be a useful means to approach some types of ureteral pathology and foreign bodies. We describe a case in which a severed surgical drain was removed from deep within the retroperitoneum by using a percutaneous retroperitoneal approach.

Aged↗
PubMed1991

Laparoscopic nephrectomy: initial case report.

A tumor-bearing right kidney was completely excised from an 85-year-old woman using a laparoscopic approach. A newly devised method for intra-abdominal organ entrapment and a recently developed laparoscopic tissue morcellator made it possible to deliver the 190 gm. kidney through an 11 mm. incision.

Adenoma↗
PubMed1991

Ureteronephroscopic marsupialization of obstructing peripelvic renal cyst.

Flexible ureteronephroscopy has been used for numerous therapeutic applications in the upper urinary tract. We report a case of a large peripelvic renal cyst causing obstruction to the ureteropelvic junction, which was treated by incising the wall of the cyst into the renal pelvis with the ureteronephroscope.

Endoscopes↗
PubMed1991

Endopyelotomy for secondary ureteropelvic junction obstruction in children.

Percutaneous endopyelotomy has been shown to be successful in treating ureteropelvic junction obstruction in adults. Little data have been published regarding this procedure in children. We describe 4 patients 6.5 weeks to 5.5 years old who underwent percutaneous endopyelotomy to treat ureteropelvic junction obstruction following failed open dismembered pyeloplasty. Preoperative obstruction was demonstrated by a nephrostogram, diuretic renogram and/or ultrasonography. Percutaneous endopyelotomy was successful in relieving the obstruction in all 4 patients, although 2 required secondary endoscopic procedures. One patient had persistent obstruction 40 days after endopyelotomy at the ureteropelvic junction and, subsequently, required percutaneous resection of a persistent flap of obstructing tissue. In another patient a ureterovesical stricture was noted at the time of stent removal, which was treated by endoscopic incision. All patients have been followed from 1.5 to 3 years postoperatively. Followup diuretic renograms, ultrasound and/or excretory urography demonstrated a patent ureteropelvic junction in all patients and all have remained asymptomatic. Endopyelotomy appears to be safe and effective in treating secondary ureteropelvic junction obstruction in children.

Child, Preschool↗
PubMed1991

Endourological treatment of ureteroenteric anastomotic strictures: long-term followup.

In 1987 we reported our initial experience with an endosurgical incisional approach to ureteroenteric anastomotic strictures (that is endoureterotomy). We have extended that initial report to encompass 15 patients with 19 ureteroenteric strictures followed for an average of 2.5 years. In all cases an endosurgical approach was well tolerated, blood loss was less than 50 cc and hospital stay averaged 3.5 days. A 16 to 22F external stent was left in place for 4 to 6 weeks postoperatively in 14 strictures. A permanent external 12F catheter was left in 5 strictures due to the presence of metastatic disease (4) and a complete dense stricture (1). The only major complication was a ureteroenteric fistula that healed over a ureteral stent without any open surgical intervention. Among 14 ureteroenteric strictures in which the stent was removed, the ureteroenteric area has remained patent in 8 (57%) with an average followup of 28.6 months (range 9 to 57 months). Failures were associated with metastatic disease in 2 cases, generalized debility in 2 and unexplained in 2. In this series an endosurgical approach to ureteroenteric strictures provided long-term satisfactory management of the problem in the majority of patients with benign and malignant disease. By current standards, only 1 patient (7%) would have been considered a candidate for open surgical repair.

Adolescent↗
PubMed1991

Comparison of intravenous sedative-analgesic techniques for outpatient immersion lithotripsy.

Fifty-three unpremedicated outpatients undergoing elective extracorporeal shock wave lithotripsy using an unmodified Dornier HM-3 lithotriptor received one of two different intravenous sedation-analgesia techniques. Both intravenous midazolam-alfentanil and fentanyl-propofol techniques produced conditions comparable to those achieved with epidural anesthesia during immersion lithotripsy. Of the two sedative-analgesic techniques, midazolam-alfentanil was associated with greater intraoperative amnesia (81% vs 38%), whereas fentanyl-propofol produced less cardiorespiratory depression and fewer postoperative side effects (e.g., pruritus). Compared with a standard epidural anesthesia technique, the mean anesthesia and recovery times were significantly shorter with the two intravenous sedation-analgesia techniques (57-62 min vs 105 min and 143-147 min vs 199 min, respectively). These data suggest that combinations of either midazolam and alfentanil or fentanyl and propofol are viable alternatives to epidural anesthesia for outpatient immersion lithotripsy.

Adult↗
PubMed1989

[Intrapleural marcaine for postoperative analgesia].

Intrapleural marcaine has been described as an effective method of analgesia following upper abdominal and thoracic operations and is no longer regarded as experimental. We have shown that the same quality of analgesia can be achieved by injecting the drug through a catheter inserted intraoperatively through the surgical incision. In our method, applied in 9 cases, there is no risk of pneumothorax as a result of piercing the chest wall, since intraoperative placement of the intrapleural catheter is very easy. We therefore suggest it as the method of choice for postoperative analgesia in kidney operations. It is especially recommended in elderly patients with chronic pulmonary disease who do not tolerate narcotics well.

Bupivacaine↗
PubMed1986

Nontraumatic spontaneous rupture of the urinary bladder.

Rupture of the urinary bladder without a history of recent trauma or instrumentation is rare; it is usually associated with bladder disease or outlet obstruction. The patient is usually seen as an emergency case and has an atypical clinical picture. The four patients in this report were initially seen and treated by a general surgeon; in only two was the diagnosis established preoperatively and confirmed by retrograde cystography. Awareness on the part of the consulting surgeon that bladder rupture is possible in a predisposed patient may lead to a correct preoperative diagnosis. In this series, early operation--removing urine from the peritoneal cavity or retropubic space, closing the rupture and securing good vesical drainage--resulted in resumption of vesical function in all four patients and there were no deaths.

Adult↗