Search PubMed⌕ Search

Biomedical subjects

T H Hsu

Publications and source records attributed to T H Hsu.

At least 37 records · Page 2Linked to original sources

The supine stress test: a simple method to detect intrinsic urethral sphincter dysfunction.

PURPOSE: A new clinical test for intrinsic urethral sphincter dysfunction is proposed and compared to abdominal leak point pressure determination by video urodynamics. MATERIALS AND METHODS: Patients were prospectively included in the study if they had stress urinary incontinence symptoms and were to undergo video urodynamic testing. Patients with urinary tract infection, cystocele, rectocele and vaginal vault prolapse were excluded from study. A supine stress test using cough and Valsalva's maneuvers was performed after bladder filling to 200 ml. with sterile normal saline solution by gravity. Efflux of the bladder solution from the meatus coinciding with the cough or Valsalva maneuver indicated a positive clinical test. A video urodynamic study, including abdominal leak point pressure, was performed. Intrinsic urethral sphincter dysfunction was diagnosed if abdominal leak point pressure was less than 100 cm. water. Test indexes were calculated based on the results of the supine stress test and the abdominal leak point pressure measurements. RESULTS: Results were positive in 30 of 41 consecutive patients and negative in 11. Using abdominal leak point pressure measurement, the supine stress test had 93.5% sensitivity, 90.0% specificity, 96.7% positive predictive value and 81.8% negative predictive value for detecting intrinsic urethral sphincter dysfunction. CONCLUSIONS: The supine stress test is easy, quick and inexpensive, and a positive test is a reliable predictor of intrinsic urethral sphincter dysfunction. A negative test is highly correlated with the absence of intrinsic urethral sphincter dysfunction during video urodynamic testing. This test is more reliable in diagnosing intrinsic urethral sphincter dysfunction than other nonurodynamic tests reported in the literature. The supine stress test can be a useful supplement to cotton swab testing for urethral hypermobility in determining the appropriate management for stress urinary incontinence.

Adult↗

Radical nephrectomy and nephroureterectomy in the octogenarian and nonagenarian: comparison of laparoscopic and open approaches.

OBJECTIVES: To retrospectively compare the outcome of laparoscopic and open radical nephrectomy or nephroureterectomy in patients 80 years old or older, inasmuch as the tolerance profile of major laparoscopic renal surgery in comparison to open surgery in the elderly patient has not been previously reported. METHODS: Since September 1997, 11 patients 80 years old or older underwent retroperitoneal laparoscopic radical nephrectomy or nephroureterectomy for cancer. These patients were compared with 6 consecutive patients 80 years old or older who underwent comparable open surgery at our institution since January 1994. No tumor had computed tomographic evidence of lymphatic, vascular, or perirenal extension. RESULTS: Baseline parameters were comparable between the laparoscopic and open groups. The laparoscopic group had a similar median surgical time (210 minutes versus 175 minutes; P = 0.1) and blood loss (150 mL versus 125 mL; P = 0.8) compared with the open group. However, specimen weight was larger in the laparoscopic group (568 g versus 292 g; P = 0.04). Moreover, the laparoscopic group had a quicker resumption of oral intake (less than 1 day versus 4 days; P <0.001), decreased narcotic requirements (14 mg versus 326 mg; P = 0.004), shorter hospital stay (2 days versus 6 days; P <0.001), and faster convalescence (14 days versus 42 days; P <0.001) compared with the open group. CONCLUSIONS: Retroperitoneal laparoscopic radical nephrectomy and nephroureterectomy are well tolerated by the elderly patient. Although our sample size was small, it appears that laparoscopy is an excellent alternative to open surgery for excision of selected renal malignancies in the octogenarian and nonagenarian population.

Aged↗

Robotic-assisted laparoscopic pyeloplasty: a pilot study.

OBJECTIVES: Robotic technology has been employed to manipulate the laparoscope during urologic procedures. However, to our knowledge, robotic technology has not been previously applied to actually perform the urologic laparoscopic procedure. The objective of this study was to determine the feasibility and efficacy of performing robotic-assisted laparoscopic pyeloplasty and compare it with conventional laparoscopic pyeloplasty in an acute porcine model. METHODS: Five female swine (10 kidneys) were prospectively randomized to undergo unstented robotic-assisted laparoscopic pyeloplasty (6 kidneys) or conventional laparoscopic pyeloplasty (4 kidneys). Robotic pyeloplasty was performed with the Zeus robotic system, which incorporates three remote-controlled interactive arms: one voice-activated arm to control the laparoscope and two robotic arms to manipulate purpose-designed instruments. Tissue dissection and transection of ureteropelvic junction area were performed manually by conventional laparoscopy. The pyeloureteric anastomosis during the robotic-assisted pyeloplasty was performed completely robotically from a remote workstation using running 5-0 absorbable sutures. Conventional laparoscopic pyeloplasty was performed manually by laparoscopic intracorporeal suturing and knot-tying techniques. Immediate patency and anastomotic integrity were evaluated by intravenous indigo carmine and ex vivo retrograde ureteropyelogram. RESULTS: In comparing robotic and conventional laparoscopic pyeloplasty, the following data were obtained: total surgical time (115.2 versus 94.5 minutes, P = 0.2), anastomosis time (75.7 versus 64.3 minutes, P = 0.3), and total number of suture-bites per ureter (13.0 versus 12.5, P = 0.8). Anastomoses were immediately watertight in 5 of 6 robotic and 3 of 4 conventional pyeloplasties. CONCLUSIONS: Robotic-assisted laparoscopic pyeloplasty is a feasible and effective procedure that may enhance surgical dexterity and precision. This has implications for clinical applications of laparoscopic telesurgery in the future.

Animals↗

Retroperitoneoscopic approach to nephrectomy.

Laparoscopic management of a variety of renal diseases has assumed an increasingly important role as an alternative to open surgery. At many institutions, the transperitoneal approach has been the more commonly employed technique because it creates a larger working space and reveals easily recognized landmarks. At the Cleveland Clinic, however, laparoscopic simple nephrectomy for benign disease and laparoscopic radical nephrectomy for cancer are preferentially approached retroperitoneoscopically. Herein, we present our technique of retroperitoneal laparoscopic nephrectomy.

Humans↗

Laparoscopic renal and adrenal surgery in obese patients: comparison to open surgery.

PURPOSE: The efficacy and morbidity of laparoscopic renal and adrenal surgery in comparison to open surgery in obese patients are unknown. This retrospective study was performed to compare the outcome of laparoscopic versus open renal and adrenal surgery in the markedly and morbidly obese patient (body mass index 30 or greater). MATERIALS AND METHODS: The study group comprised all obese patients undergoing laparoscopic renal and adrenal surgery (laparoscopic group) from August 1997 to February 1998 at our institution. The majority of procedures were performed using a retroperitoneoscopic approach via the flank. These patients were compared with all obese patients undergoing open renal and adrenal surgery (open group) from 1994 to 1998. Open group patients with factors precluding laparoscopic surgery were excluded from the study (mass greater than 10 cm., renal vein and/or inferior vena caval thrombus and extension outside Gerota's fascia). RESULTS: There were 21 obese patients in each group and baseline parameters were comparable between groups. Median body mass index in the laparoscopic and open groups was 34 and 31, respectively. Median surgical time between the laparoscopic (210 minutes) and open (185) groups was comparable (p = 0.16). However, the laparoscopic group had decreased blood loss (100 versus 350 ml., p<0.001), quicker resumption of oral intake and ambulation (less than 1 versus 5 days, p<0.001), decreased narcotic analgesic requirements (12 versus 279 mg., p<0.001), shorter median hospital stay (less than 1 versus 5 days, p<0.001) and quicker convalescence (3 versus 9 weeks, p<0.001). There were 6 complications in 4 laparoscopic cases and 14 in 9 open surgery cases (p = 0.16). CONCLUSIONS: Markedly obese patients have an increased risk of complications from surgery, regardless of the approach. Our data suggest that laparoscopic renal and adrenal surgery is technically feasible in the markedly and morbidly obese patient, and compared with open surgery results in significantly decreased blood loss, quicker return of bowel function, less analgesic requirement, shorter convalescence and reduced hospital stay.

Adrenal Gland Neoplasms↗

Acetylcholine and tachykinin receptor antagonists attenuate wood smoke-induced bronchoconstriction in guinea pigs.

To study the mechanisms of wood smoke-induced bronchoconstriction, we measured total lung resistance (RL) and dynamic lung compliance (Cdyn) in anesthetized and mechanically ventilated guinea pigs. Airway exposure to various doses of wood smoke (lauan wood; 5, 10, and 15 breaths) resulted in a dose-dependent increase in RL and decrease in Cdyn. The smoke-induced changes in RL and Cdyn were significantly attenuated by pretreatment with atropine, CP-96,345 [(2S,3S)-cis-2-(diphenylmethyl)-N-((2-methoxyphenyl)-methyl)-1-aza bicyclo(2.2.2.)-octan-3-amine; a tachykinin NK1 receptor antagonist], and SR-48,968 [(S)-N-methyl-N(4-(4-acetylamino-4-phenylpiperidino)-2-(3,4-dichlorophen yl)-butyl)benzamide; a tachykinin NK2 receptor antagonist] in combination, atropine alone, and SR-48,968 alone, but were not significantly affected by pretreatment with the inactive enantiomers of CP-96,345 and SR-48,968, CP-96,345 alone, indomethacin (a cyclooxygenase inhibitor), and MK-571 [((3-(3-(2-(7-chloro-2-quinolinyl)ethenyl)phenyl((3-dimethyl amino-3-oxo-propyl)thio)methyl)propanoic acid; a leukotriene D4 receptor antagonist]. The activity of airway neutral endopeptidase, a major enzyme for tachykinin degradation, was not significantly influenced by wood smoke during the development of bronchoconstriction. We conclude that: (1) both cholinergic mechanisms and endogenous tachykinins, but not cyclooxygenase products or leukotriene D4, play an important role in the acute bronchoconstriction induced by wood smoke, and (2) the contribution of tachykinins to this airway response is primarily mediated via the activation of tachykinin NK2 receptors, but is not associated with inactivation of the airway neutral endopeptidase.

Animals↗

Smoke-induced airway hyperresponsiveness to inhaled wood smoke in guinea pigs: tachykininergic and cholinergic mechanisms.

The smoke-induced airway hyperresponsiveness (SIAHR) to inhaled wood smoke was investigated in anesthetized guinea pigs. Two smoke challenges (each 10 ml) separated by 30 min were delivered into the lungs by a respirator. In control animals, SIAHR was evidenced by an average bronchoconstrictive response (an increase in total lung resistance) to the second smoke challenge (SM2) that was approximately 4.3-fold greater than that to the first challenge (SM1). Pretreatment with CP-96,345 and SR-48,968 (neurokinin-1 and -2 receptor antagonists; each 1 mg/kg) in combination totally prevented this SIAHR, while pretreatment with CP-96,344 and SR48,965 (inactive enantiomers of CP-96,345 and SR-48,968, each 1 mg/kg) in combination failed to do so. Pretreatment with CP-96,345 (1 mg/kg), SR48,968 (1 mg/kg), or atropine (50 microg/kg) significantly alleviated this SIAHR. Pretreatment with phosphoramidon [an inhibitor of neutral endopeptidase (NEP); 2 mg/kg], which suppresses the degradation of tachykinins, induced an increase in airway reactivity that largely mimicked this SIAHR. The NEP activity measured in airway tissues excised 30 min after SM1 was significantly lower than that in air control value. These results suggest that 1) a prior wood smoke exposure induces an airway hyperresponsiveness to the subsequent wood smoke inhalation, 2) a tachykininergic mechanism involving both neurokinin-1 and -2 receptors is essential for, and a cholinergic mechanism is also involved in the development of this SIAHR, and 3) inactivation of airway NEP by wood smoke may contribute to this SIAHR.

Airway Resistance↗

Metabolic abnormalities in patients with caliceal diverticular calculi.

PURPOSE: We determined the incidence and spectrum of metabolic abnormalities in patients with caliceal diverticular calculi. MATERIALS AND METHODS: Five men and 9 women with caliceal diverticular calculi underwent metabolic evaluation, including determination of serum electrolytes, calcium, phosphate and uric acid, and 24-hour urinary volume, creatinine, calcium, oxalate, uric acid and citrate. RESULTS: Of the 14 patients 7 (50%) had urinary excretion abnormalities promoting stone formation, including hypercalciuria in 3, hyperoxaluria in 1, hypercalciuria combined with hyperuricosuria in 1 and hyperoxaluria combined with hyperuricosuria in 2. Two patients had a history of gout while another had radiographic evidence of medullary sponge kidney. Of the patients 9 (64.3%) had a history of synchronous or metachronous calculi distant from the involved caliceal diverticular stone and 5 (55.6%) of these 9 had definable metabolic disorders. However, there was no statistically significant difference in urinary excretion values between patients with or without a history of additional extra diverticular stones. CONCLUSIONS: Urinary stasis alone does not explain stone formation in a significant number of patients with caliceal diverticular calculi. Rather, the local physiological environment of the urine likely has a predisposing role and evaluation for metabolic abnormalities should be considered. In some patients cure may be effected by treating the stone and any associated metabolic disorders rather than the diverticulum.

Adult↗

Complicated urinary tract infection: analysis of 179 patients.

BACKGROUND: The aim of our study was to investigate the incidence, bacteriology, management and outcome of complicated urinary tract infections (UTIs) at the Veterans General Hospital-Taipei. METHODS: Between June, 1993, and July, 1994, medical records of 2,566 patients admitted to the Division of Urology, Veterans General Hospital-Taipei, were retrospectively reviewed. Of these patient, 1,322 had a diagnosis of benign prostatic hyperplasia (BPH), 607 were admitted for renal stones, 496 for ureteral stones, 75 for transitional cell carcinoma (TCC) of the urinary bladder, 47 for renal tumors and 19 for TCC of the ureter. Among all patients studied, 179 (6.98%) acquired a complicated UTI. Of these, 81 were admitted for BPH, 46 for renal stones, 42 for ureteral stones, five for TCC of the urinary bladder, three for renal tumors and two for TCC of the ureter. RESULTS: Of the 179 patients with complicated UTIs, 155 were men and 24 were women. The urine culture positive rate was 76.0% (136/179) and the most common bacteria were Escherichia coli, Proteus mirabilis and Pseudomonas aeruginosa. The principle mode of treatment included parenteral antibiotics and urinary diversion (percutaneous nephrostomy and Foley catheterization), when necessary. The infection control rate for these complicated UTIs was 96.3% for BPH, 95.5% for renal stone, 97.6% for ureteral stone, 80% for TCC of the urinary bladder, 100% for renal tumor and 100% for TCC of the ureter. Mortality due to complicated UTI was 3.9% (7/179). CONCLUSIONS: We concluded that the prognosis of complicated UTI is good if diagnosis and appropriate treatment are given promptly. Early drainage to relieve obstruction and intravenous antibiotics are initially necessary. Surgical intervention is required to resolve functional or structural abnormalities after the UTI has been controlled.

Adult↗

Involvement of hydroxyl radical in the immediate ventilatory responses to inhaled wood smoke in rats.

Spontaneous inhalation of wood smoke (approximately 6 ml) via a tracheostomy immediately triggered either a slowing of respiration (SR, n = 51) or an augmented inspiration (AI, n = 32) in 83 anesthetized Sprague-Dawley rats studied. To investigate the involvement of hydroxyl radical (OH.) in evoking these immediate smoke-induced ventilatory responses, smoke challenges were repeated following intravenous infusion (0.05 ml/min for 20 min) of saline vehicle, dimethylthiourea (DMTU, 500 mg/kg), deferoxamine (DEF, 20 mg/kg), or iron-saturated DEF (DEF + Fe, 20 mg/kg). DMTU is a scavenger for OH.. DEF is an iron-chelator which prevents the formation of OH., whereas DEF saturated with iron results in the loss of its iron-chelating properties. In the vehicle group, both the SR (n = 8) and the AI (n = 7) were unaffected by the pretreatment. However, in the DMTU group, the SR (n = 23) was abolished in seven and attenuated in 16 rats, while the AI (n = 10) was eliminated in eight and unaffected in two rats. In the DEF group, the SR (n = 12) was abolished in three and attenuated in nine rats, while the AI (n = 8) was eliminated in six and unaffected in two rats. In contrast, in the DEF + Fe group, both the SR (n = 8) and the AI (n = 7) were not attenuated by the pretreatment. These results suggest that an increase in OH. burden following smoke inhalation is actively involved in evoking the acute irritant effects of wood smoke on breathing in rats.

Animals↗

The significance of serum alkaline phosphatase bone isoenzyme in prostatic carcinoma with bony metastasis.

OBJECTIVE: To evaluate the clinical significance of serum alkaline phosphatase (ALP). ALP bone isoenzyme (ALPb) and prostate specific antigen (PSA) levels in predicting bony metastasis in prostatic carcinoma. PATIENTS AND METHODS: The levels of serum ALP, ALPb and PSA were assessed in 32 patients with prostatic carcinoma and bony metastasis (group 1), 31 with prostatic carcinoma without bony metastasis (group 2), and 31 with benign prostatic hyperplasia (group 3). Bony metastases were detected using whole-body bone scintigraphy and ALPb was estimated electrophoretically before surgical or medical treatment. The levels of the three markers were compared for their ability to predict bony metastasis. RESULTS: In groups 1, 2 and 3, respectively, the mean (SD) serum levels of ALP were 304 (322.2), 76.6 (47.5) and 63.8 (14.7) IU/L, of ALPb were 79.9 (76.9), 23.6 (9.9) and 25.3 (9.0) IU/L and of PSA were 478.1 (352.2), 46.9 (32.1) and 8.1 (1.8) ng/mL. The differences in serum ALP and ALPb between groups 1 and 2, and between groups 1 and 3 were significant (P < 0.05), but not those between groups 2 and 3. The positive predictive value (PPV) for bony metastasis in patients with prostatic carcinoma was 91.3% (21/23) and 100% (18/18) and the negative predictive value (NPV) was 71.8% (28/39) and 68.9% (31/45) for ALP and ALPb, respectively. CONCLUSION: Both serum ALP and ALPb were increased significantly in patients with prostatic carcinoma with bony metastasis. The level of ALPb had a higher PPV and specificity for bony metastasis than had the level of ALP, but a lower NPV and sensitivity than ALP or PSA (at PSA levels > 20 ng/mL).

Aged↗

Is renal function at the tumor side a prognostic factor in ureteral transitional cell carcinoma?

OBJECTIVES: To evaluate whether the ipsilateral renal function on the tumor side is a prognostic factor in transitional cell carcinoma (TCC) of the ureter. PATIENTS AND METHODS: We retrospectively reviewed 129 consecutive patients with ureteral TCC between September 1973 and July 1993 at our hospital. There were 98 males and 31 females aged from 31 to 84 years (mean 64.9). Of them, 126 patients who received intravenous pyelography (IVP) were divided into 3 groups according to their radiological findings (group 1: nonvisualization of kidney at tumor side; group 2: hydronephrosis or hydroureter; group 3: no obstruction). Eighty patients receiving radionuclide (131I-hippuran) renal function test (RRFT) with available effective renal plasma flow (ERPF) were divided into 2 groups using ipsilateral ERPF 50 ml/min as a cutoff value (group 1: < 50 ml/min; group 2: > or = 50 ml/min). The mean survival of each group was estimated by the Kaplan-Meier method. RESULTS: For patients receiving IVP, the mean survivals were 61.7, 99.7 and 83.8 months for groups 1, 2, and 3, respectively, and the differences between each 2 of the 3 groups were statistically significant (p < 0.05). For patients having RRFT, the mean survivals were 65.8 months for group 1 and 89.2 months for group 2 patients, and the difference between them was statistically significant (p < 0.05). When renal function, tumor number, grade, stage and type of treatment were analyzed using a multivariate method, only tumor stage was statistically significant as a prognostic factor. CONCLUSION: Ipsilateral renal function at the tumor side is not a good prognostic factor for patients with ureteral TCC. However, when the stage of tumor is not available, renal function at the tumor side may provide an implication of the patient's prognosis.

Adult↗

The significance of tumour grade in predicting disease progression in stage Ta transitional cell carcinoma of the urinary bladder.

OBJECTIVE: To determine the significance of tumour grade in predicting disease progression in stage Ta transitional cell carcinoma (TCC) of the urinary bladder. PATIENTS AND METHODS: From August 1975 to January 1991, 140 patients (121 men and 19 women, mean age 64.2 years, range 30-83) with stage Ta TCC of the urinary bladder were treated at the Veterans General Hospital-Taipei by transurethral resection and post-operative adjuvant intravesical chemotherapy. There were 48 patients (34%) with grade 1, 78 patients (56%) with grade 2 and 14 patients (10%) with grade 3 tumours. Disease progression and muscle invasion were assessed during a mean follow-up of 74.3 months and related to grade, urine cytology and the number and location of tumours. RESULTS: A total of 10 patients (7%) had tumour recurrence which invaded the muscle, of whom one had grade 1, six had grade 2 and three had grade 3 tumours. The patient with a grade 1 tumour developed muscle invasion within 16 months of surgery. The mean interval to the development of muscle invasion was 49.2 months in patients with grade 2 and 39.4 months with grade 3 tumour. In patients with stage Ta TCC, a grade 3 tumour was more likely to progress to muscle invasion (21%) than was a grade 1 (2.1%; P < 0.05) or grade 2 (7.7%; P < 0.05) tumour. One patient with a grade 2 and one patient with grade 3 tumour developed distant metastases without muscle invasion. Overall, the disease progression rate was 8.6% (12/140) in stage Ta TCC. Disease progression was more common with grade 3 (28.5%) than with grade 2 (9.0%; P < 0.05) and grade 1 (2.1%; P < 0.05) tumours. CONCLUSION: Tumour grade may be used to predict disease progression after resection of stage Ta urinary bladder cancer. A higher grade of tumour was associated with a higher incidence of disease progression.

Administration, Intravesical↗

Alterations of mitochondrial oxidative metabolism in rabbit urinary bladder after partial outlet obstruction.

Previous studies demonstrated that one of the most significant cellular responses of the rabbit urinary bladder to partial outlet obstruction is a 50% decrease in the activities of the mitochondrial enzymes citrate synthase and malate dehydrogenase, when calculated as either activity per unit mass or activity per mg protein. A major question arose from these studies: Are the mitochondrial enzyme activities per mitochondrion reduced, or is the number of mitochondria per unit tissue mass reduced? The current experiments were designed to study the sequential changes in the activities of mitochondrial oxidative enzymes following partial outlet obstruction. The activities of NADH-cytochrome c reductase (NCCR), cytochrome oxidase (CO), citrate synthase (CS) and malate dehydrogenase (MDH) were measured in whole tissue homogenates and in mitochondrial preparations of separated bladder mucosa and muscle, from normal bladders, and, from hypertrophied bladders at 1, 3, and 7 days following partial outlet obstruction. The results can be summarized as follows: 1) Whole tissue homogenates: Activities of all enzymes were reduced to approximately 50% of control at 1 day following partial outlet obstruction. NCCR and CO activities returned to 75 and 85% of control respectively by 7 days post-obstruction; CS activity did not show any significant recovery over the 7 day period. 2) Mucosal and smooth muscle mitochondrial preparations: Activities of all enzymes were decreased significantly by 50% or greater at 1 day following partial outlet obstruction. The cytochrome (NCCR and CO) enzyme activities returned to control levels by 7 days post-obstruction; CS activity showed only a minor recovery over this time period. These results show that mitochondrial enzyme activity is significantly impaired immediately following partial outlet outlet obstruction, and whereas the activity of the cytochrome enzymes NCCR and CO recover to control levels (in the mitochondrial preparations) within 7 days post obstruction, the Krebs cycle enzymes (CS and MD) show no significant recovery. Thus, the regulatory mechanisms for the cytochromes is significantly different from that for the enzymes of the krebs cycle.

Animals↗

Partial outlet obstruction of the rabbit bladder results in changes in the mitochondrial genetic system.

In the rabbit, partial outlet obstruction of the urinary bladder results in significant changes in the physiology, cellular structure, and cellular metabolism of that organ. One of the most striking changes observed is a 50% decrease in oxidative metabolism. Here we investigate whether the function of the mitochondrial (mt) genetic system is altered in rabbit bladder tissue following partial outlet obstruction. Southern analyses of total DNA prepared from bladder tissue excised as a function of time after initiation of partial outlet obstruction showed that the relative number of copies of the mt genome decreases as much as 10-fold during the first 7 d after obstruction, and that this attenuated mt genome copy number is maintained until at least 14 d post-obstruction. Northern analyses, in contrast, showed that mt COII and cytochrome b transcript levels initially decrease but recover to control levels by about 5 d after obstruction; that level is maintained through 14 d post-obstruction. Enzymatic analysis of cytochrome oxidase and NADH cytochrome c reductase activities in obstructed bladder tissue gave results which paralleled the pattern in the mt RNA analyses. Surprisingly, transcript levels for the mt-related nuclear COIV gene rapidly decreased to about 50% of control levels following obstruction and remained there until 14 d post-obstruction. These results indicate that partial outlet obstruction of the rabbit bladder leads to significant changes in the status and expression of the mt genetic system in bladder tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Morphological change in the urothelium after electrohydraulic versus pulsed dye laser lithotripsy.

OBJECTIVE: To observe morphological changes in the urothelium after exposure to laser beam and electrohydraulic spark. MATERIALS AND METHODS: The pulse dye laser lithotripter (MDL-2, Candela Corporation, Boston, USA) and the electrohydraulic lithotripter (AEH-2, Circon ACMI Corporation Stamford, USA) were used directly on the bladder mucosa in six pigs. Immediately after treatment, the bladder mucosa was prepared for light microscopic and scanning electron microscopic examination. RESULTS: Both electrohydraulic spark and laser beam caused mucosal denudation, submucosal swelling and haemorrhage. There was a positive correlation between the degree of urothelial damage and the power and pulse numbers applied. CONCLUSION: Direct contact of the urothelium in patients treated with laser beam or electrohydraulic spark should be avoided.

Animals↗

Efficacy of in vitro stone fragmentation by extracorporeal, electrohydraulic, and pulsed-dye laser lithotripsy.

Fragmentation has become the standard therapy for urinary calculi in the modern era. Stone fragility as well as position and size are important for the determination of a treatment program. To compare the efficacy of stone fragmentation, seven kinds of human urinary calculi with known composition (calcium oxalate monohydrate and dihydrate, dibasic calcium phosphate, uric acid, struvite, calcium phosphate, and cystine) were treated by three fragmentation techniques commonly used, namely extracorporeal shock wave (SWL), electrohydraulic (EHL), and pulsed-dye laser lithotripsy. Uric acid, calcium oxalate dihydrate, and calcium phosphate stones could be destroyed easily by any of these methods. Struvite was soft but sticky and not easy to break into tiny particles. Both dibasic calcium phosphate and calcium oxalate monohydrate stones were resistant to the laser and EHL; SWL is the treatment of choice. For cystine stones, none of the treatments was satisfactory; SWL was the only way to break them into large pieces.

Calcium Oxalate↗