QCD and strongly coupled gauge theories: challenges and perspectives.

We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.

A new generation of semirigid fiberoptic ureteroscopes.

BACKGROUND: Further advances in endoscope technology have allowed the development of a new generation of tightly packed fiberoptics encased within a rigid ureteroscope. The tips of these semirigid ureteroscopes measure between 5.0F and 11.9F, and their working channels measure between 1.8F and 5.5F, which allows passage of routine endoscopc instruments. Additionally, several manufacturers have recently produced straight-channel fiberoptic semirigid endoscopes with an offset lens which allow usage of rigid lithotripsy devices. New fiber-packing techniques provide numerous pixels within the image bundle. These ureteroscopes have varied distal lens systems, but all have excellent vision in the field of view. METHODS: Over the past 28 months, we have performed transurethral ureteroscopy in 187 patients, having utilized semirigid ureteroscopes in 158 patients for diagnostic procedures (8.7 %), stone manipulation (78.7 %), removal of migrated stents (4.4%), and surgery of stricture, tumor, or foreign bodies (8.2%). In more than 50% of our cases, ureteral dilation was not necessary, and the semirigid ureteroscope was passed to the area of interest without difficulty. RESULTS: We accessed the site of pathology in 96.2% of patients. Overall, complications occurred in 6.9% of patients. However, of these problems, 93.6% were small ureteral perforations (only three of which were caused by the semirigid ureteroscope itself), and all cases but one were managed successfully by a ureteral stent. No postoperative strictures were noted. CONCLUSION: This new generation of semirigid fiberoptic ureteroscopes represents another significant advance in the endourologic management of ureteral disease.

Lipid peroxidation induced by shockwave lithotripsy.

To determine the relation between high-energy shockwaves (HESW) and the presence of lipid peroxidation produces, juvenile pigs were subjected to shockwave lithotripsy (SWL). After lithotripsy, both treated and control kidneys were analyzed, along with urine samples collected before, during, and after SWL. Thiobarbituric acid-reactive substance (TBARS) and lipid-conjugated diene (CD) concentrations, used as markers for membrane lipid peroxidation, were determined in the kidney and urine samples. Significantly increased mean TBARS concentrations (146%) were associated with homogenates of lithotripsy-treated kidneys, 77.8 +/- 14.4 (SD) mmol/g v the controls, 31.4 +/- 14.9 mmol/g. Lithotripsy induction of lipid peroxidation products in the cortex, the gross damage site, and the respective medulla were also examined. In HESW-treated cortex samples, increased TBARS concentrations were seen--75.0 +/- 21.3 mmol/g--compared with untreated controls-- 45.2+/- 5.6 mmol/g--while increased CD concentrations (168%) were observed in the medulla of HESW-treated samples. No significant differences were observed in TBARS or CD concentrations in urine samples from control or treated kidneys, yet specific lipid hydroperperoxides were detected in the urine of HESW-treated kidneys. We conclude that HESW lithotripsy of swine kidneys is associated with increased lipid peroxidation products that may cause further cellular damage. Lipid peroxidation induced by SWL may be one of several mechanisms that lead to other potential bioeffects. Finally, analysis of specific lipid hydroperoxides in the urine of HESW-treated kidneys may serve as a noninvasive marker of renal injury after clinical SWL.

Management of calyceal calculi.

Management of calyceal calculi has changed dramatically during the past 20 years. Minimally invasive techniques virtually have replaced open surgical stone removal. Even large and complex calyceal calculi may be treated effectively with these minimally invasive techniques. Although open surgical stone removal is performed infrequently, a clear understanding of the subtle renal anatomy aids the urologist in more effectively treating patients with calyceal calculi and in limiting surgical complications.

Struvite calculi.

Although calcium oxalate stones are the most common type of calculi found in the United States, struvite or infection stones are quite common and generally pose a difficult treatment dilemma. The presence of urinary infection with a urease-producing organism is necessary for these stones to form. Proteus species account for the majority of infections that cause struvite stones in all age ranges. However, other organisms also produce urease and may be detected in conjunction with struvite calculi. Factors that may predispose one to urinary tract infections increase the likelihood of struvite stone formation. Several options are available for the treatment of existing struvite calculi. Smaller stones may be treated with primary shock-wave lithotripsy, whereas larger stones are more appropriately managed with percutaneous or combination procedures. Medical therapy to prevent recurrent stone formation is also an essential part of the treatment of these patients, as the risk of stone recurrence is extremely high. Antibiotic therapy and urease inhibitors perhaps offer the best form of preventative treatment available today.

Long-term follow-up of Acucise incision of ureteropelvic junction obstruction and ureteral strictures.

OBJECTIVES: There are few data on the long-term effectiveness of various endoureterotomy procedures. One such technique for the treatment of ureteral strictures and ureteropelvic junction (UPJ) obstruction utilizes a recently developed ureteral cutting balloon catheter, Acucise. This device may be used under fluoroscopic guidance alone, which significantly reduces operating time. The purpose of this study is to determine the long-term efficacy of the Acucise balloon in treatment of ureteral strictures and UPJ obstruction. METHODS: Fifteen patients have been treated with the Acucise balloon, with an average follow-up of 21.6 months. Five of the patients have been followed for more than 2 years, and 11 of the patients had greater than 1 year follow-up. RESULTS: The overall success rate, defined as resolution of obstruction radiographically or disappearance of symptoms, or both, was 73%, with only 4 overt failures. All but one of the procedures were completed in 45 minutes or less, and 13 of the 15 patients were treated as outpatients. There were two significant complications. Seventy-five percent (3 of 4) of the treatment failures occurred within the first 4 months following original procedure. Of the 4 total failures. 2 patients had ureteral strictures greater than 2 cm in length, which were likely ischemic in nature secondary to previous surgeries. One patient, with a primary UPJ obstruction, was found to have a crossing vessel at subsequent open pyeloplasty. CONCLUSIONS: The Acucise cutting balloon offers the urologist a rapid and effective alternative for the management of ureteral strictures and UPJ obstruction. In our experience, early results (3 to 4 months) are usually indicative of long-term success. Proper patient selection may further improve long-term results of this simple, innovative technique.

Long-term incidence and risks for recurrent stones following contemporary management of upper tract calculi in patients with a urinary diversion.

PURPOSE: The long-term rate of stone recurrence following contemporary minimally invasive management of calculi was determined in patients with urinary diversion and to identify specific risk factors for these recurrences. MATERIALS AND METHODS: We followed for a minimum of 12 months 25 patients (29 renal units) with upper tract calculi associated with urinary diversion, and treated with extracorporeal shock wave lithotripsy and/or percutaneous nephrostolithotomy. The risk of recurrent stones at 5 years was determined by a Kaplan-Meier estimate, while potential risk factors for recurrence were analyzed using a log-rank comparison. RESULTS: Stones recurred in 8 patients (32%) 18 to 61 months (mean 27.0) after treatment. The risk of new stone formation after 5 years was estimated to be 63.3% and was significantly greater in patients with recurrent bacteriuria after treatment. Neither stone history, type of procedure used, stone composition nor radiographic status at completion of treatment significantly influenced this risk. CONCLUSIONS: Contemporary management of upper tract calculi in patients with a urinary diversion is associated with a high recurrence rate, especially among those with recurrent bacteriuria, regardless of whether the patient is initially rendered stone-free. Continued close surveillance and antibiotic prophylaxis seem to be essential in this high risk patient population.

Transfer of endogenous retroviral superantigen from donor to recipient B cells following priming to induce peripheral T cell tolerance.

Endogenous retroviral superantigens such as vSAG-7 are highly stimulatory for T cells through interaction with the T cell receptor on the basis of V beta usage. Priming of adult MMTV 7-negative mice with vSAG-7-expressing cells has been shown to result in peripheral V beta 6/CD4+ T cell activation followed by tolerance to further interaction with the superantigen. The goal of the current study was to examine the cells presenting vSAG-7 during this initial burst of in vivo T cell activation. Priming of MMTV 7-negative BALB/c (H-2d) mice with DBA/2 (H-2d, MMTV 7+) spleen cells resulted in a 5- to 12-fold increase in the number of B cells in the lymph nodes. These B cells expressed increased levels of I-A and I-E class II MHC determinants. Use of MMTV 7-negative CB.17 (H-2d, Ighb) mice as recipients of DBA/2 (Igha) cells indicated that the increased number of B cells was of host, rather than donor, origin. The number of donor-derived (IgM/B220+) B cells observed during the course of vSAG-7-reactive V beta 6/CD4+ T cell activation was very low. Proliferation of unprimed T cells from MMTV 7-negative mice was induced during coculture with B cells from the lymph nodes of vSAG-7-primed recipients and was blocked by anti-class II MHC antibodies, as well as by an anti-vSAG-7 antibody. Highly purified host B cells from vSAG-7-primed recipients specifically stimulated the blastogenesis of V beta 6/CD4+ T cells in vitro. Collectively, the results indicate that following priming to induce peripheral tolerance, vSAG-7 is transferred from donor cells to class II MHC determinants on recipient B cells and is presented to the T cell repertoire by the autologous B cells.

Clinical effect of captopril on the formation and growth of cystine calculi.

We determined the clinical efficacy of captopril for the prevention of new or stone growth in patients with homozygous cystinuria. Nine patients with a history of multiple cystine stones despite standard fluid and alkalization therapy received 50 mg. captopril, 3 times daily in addition to the standard therapy. Before treatment the rate of new stone formation or stone growth ranged from 0.7 to 2.0 events (mean 1.2) per patient-year for 1 to 3 years of observation (mean 1.9). During treatment the rate ranged from 0 to 3.0 events (mean 1.03) per patient-year for 0.5 to 6 years (mean 2.9). Although statistical significance was not evident for the group as a whole (p = 0.35), our findings suggest that captopril may be clinically efficacious in at least some patients with difficult to control cystinuria. Recommendations regarding its indications in this setting are made.

Selective minimally invasive management of calculi in patients with urinary diversions.

We evaluate the efficacy of selectively applied minimally invasive management of calculi in 30 patients with urinary diversions (ileal/jejunal conduit in 23, cutaneous ureterostomy in 2, nonrefluxing colon conduit in 4 and ureterosigmoidostomy in 1). Upper tract calculi in 38 renal units were managed with extracorporeal shock wave lithotripsy or endo-urologically. Patients were divided into 3 treatment groups determined primarily by stone size and location: group 1-25 renal units with a mean stone burden of 1.78 cm.2 treated with extracorporeal shock wave lithotripsy alone, group 2-7 renal units with a mean stone burden of 12.75 cm.2 treated with percutaneous nephrostolithotomy alone and group 3-6 renal units with a mean stone burden of 19.03 cm.2 treated with a combination of both procedures. Stone-free results were 92%, 100% and 67% in groups 1 to 3, respectively. Total hospital stay averaged 4.3, 11.1 and 13.7 nights, while complications occurred in 1, 3 and 2 patients, respectively. We conclude that selective application of contemporary techniques for minimally invasive management of calculi in patients with a urinary diversion can provide acceptable results, even with progressively large and complex stone burdens, and that these results will be equivalent to those achieved in patients without urinary diversion.

Minimally invasive endourologic management of calculi in continent urinary reservoirs.

This study was done to determine whether minimally invasive endourologic management of calculi in continent reservoirs can be done effectively without compromise of urinary continence. Four patients with continent urinary diversions (1 Indiana pouch and 3 Kock pouches) were managed with trans-stomal pouchoscopic ultrasonic lithotripsy (n = 2), prone position extracorporeal shock wave lithotripsy (n = 1), or a "sandwich" combination of these (n = 1) for stone burdens up to 20 cm2. Total hospital stay ranged from one to four (mean = 2.6) days. All 4 patients were initially rendered stone free, and, with follow-up as long as twenty-five months, only 1 has had a recurrence. No patient experienced stomal leakage or other complications. This study suggests that minimally invasive endourologic management of calculi in continent urinary reservoirs can be done safely and effectively to obviate the need for more invasive percutaneous approaches or open surgery, even for some patients with large stone burdens.

Reoperation for cryptorchid testis in prepubertal child.

Twenty-two prepubertal patients with cryptorchid testes after having previous inguinal surgery were referred. These included 17 patients in whom orchidopexy had been unsuccessful. Five patients had prior surgery for hernia and/or hydrocele resulting in surgical entrapment of the testis. Five patients had bilateral disease. In 1 patient the testis was involved in Marlex mesh, 1 had had two prior orchidopexies, and 1 had prune belly syndrome. Postoperatively the testes were in good position in the scrotum in all 22 cases, with mean follow-up of 8.9 months. All testes were of normal size, and no atrophic testes ensued following the procedures. Principle factors for success in re-exploration included initial retrograde dissection of the testis and cord, intraperitoneal exposure, and subsequent dissection and adequate lengthening of the cord with protection of the spermatic vessels.