Monitoring sessile droplet evaporation on a micromechanical device.

A bulk acoustic mode micro-electro-mechanical dual resonator platform is utilised to study the evaporation of sub-microliter water droplets from the surface of the resonator. An analytical formulation for the observed frequency shift and the measure dependence of resonant frequency on the modes of evaporation which is consistent with the optically derived data. The resonators access only a thin layer of the liquid through shear contact and, hence, the response is not affected by the bulk mass of the droplet to first order. A relationship between the droplet contact area and the elapsed time was established for the evaporation process and is used to derive a value of the diffusion coefficient of water in air that is found to be in reasonable agreement with literature values. This work introduces a new tool for the electro-mechanical monitoring of droplet evaporation with relevance to applications such as biosensing in liquid samples of sub-microliter volumes.

Evidence of possible carcinogenesis during conformational changes in bladder mucosa induced by bladder outlet obstruction.

Fourier transform infrared spectroscopy with attenuated total reflectance technique was applied to determine the mucosa on the surface of the rabbit urinary bladder wall before and after obstruction. Several abnormal spectra related to the hydrogen bonding in nucleic acids of protein, previously found in the colon malignant tissues, appeared in the infrared spectra of the obstructed bladder mucosa, which could not be found in normal bladder mucosa. Urinary bladder outlet obstruction seemed to induce carcinogenesis in the obstructed bladder mucosa by forming several infrared spectral abnormalities.

Sexual dysfunction in men with lower urinary tract symptoms.

The conventional view that sexual function is not adversely affected by lower urinary tract symptoms (LUTS), assumed to be caused by enlargement secondary to benign prostatic hyperplasia (BPH), was investigated in this study of 423 men aged 40 years and over in a community population in the UK and 1271 urology clinic attenders aged 45 years and over in 12 countries, using the ICSmale and ICSsex questionnaires. Sexual dysfunction was found to be common: in the community, age standardized prevalences of reduced rigidity of erections were 53%, reduced ejaculation 47%, and pain on ejaculation 5%; in clinic men, age standardized prevalences of reduced rigidity of erections were 60%, reduced ejaculation 62%, and pain on ejaculation 17%. Sex lives were reported to be spoiled by LUTS in 8% of community men and 46% in the clinic. There were negative trends for age in the extent to which clinic men were bothered by these symptoms, although older men were still very concerned. Significantly raised odds ratios of sexual dysfunction were found in those with LUTS, especially storage symptoms associated with incontinence. Urinary flow rates were not associated with sexual symptoms. Sexual dysfunction is, therefore, strongly associated with LUTS, is a matter of concern to the men affected, and should be taken into account when managing patients with LUTS.

Clinical outcome at 3 months after transurethral vaporization of prostate for benign prostatic hyperplasia.

OBJECTIVES: To evaluate the clinical outcome of transurethral vaporization of the prostate (TUVP) for the management of benign prostatic hyperplasia (BPH). METHODS: Between March and June 1995, 30 patients with symptomatic BPH treated by TUVP were enrolled in this study. Transrectal ultrasonography (TRUS) was done preoperatively. American Urological Association (AUA) symptom score determination, pressure flow study, and questionnaire (for evaluating potency) were done preoperatively and 3 months postoperatively. RESULTS: The average age was 70.5 years (range 60 to 83) and estimated prostate size by TRUS before surgery was 33.8 +/- 14.0 g. The average AUA symptom score decreased significantly 3 months after TUVP (6.2 +/- 7.8 versus 18.2 +/- 9.0; P < 0.01). The maximum urine flow rate (Qmax) was 11.1 +/- 3.7 mL/min before TUVP (mean +/- SD) and 17.0 +/- 6.5 mL/min 3 months after TUVP, whereas the detrusor pressure at maximum urine flow (Pdes at Qmax) was 61.0 +/- 23.9 and 41.2 +/- 15.2 cm H2O, respectively. Qmax increased and Pdes at Qmax decreased significantly 3 months after TUVP. Of the 30 patients, 3 (10%) developed bladder neck contracture. Of the 24 patients who were potent sexually before operation, 3 (12.5%) developed impotence 3 months after surgery. CONCLUSIONS: TUVP is an effective alternative surgical procedure to relieve obstruction for patients with symptomatic BPH. However, cautious attitude on its usage is advocated based on our preliminary results indicating the occurrence of late complication such as impotence and bladder neck contracture.

Femoral neuropathy after pelvic surgery.

Femoral neuropathy is an uncommon complication following pelvic surgery. We report on 2 cases of femoral nerve injury after pelvic surgery: 1 patient received radical cystectomy due to invasive transitional cell carcinoma of the urinary bladder, and the other patient had a transurethral resection of the bladder and received exploration and biopsy of a tumor mass over the right sacroiliac joint area. Pathogenesis and prevention of the complication of femoral neuropathy are discussed in the following report.

Cisplatin-based chemotherapy for the treatment of advanced transitional-cell carcinoma of the urinary tract--a preliminary report.

The CMV (cisplatin, methotrexate, and vinblastine) and M-VAC (methotrexate, vinblastine, doxorubicin, and cisplatin) regimens were used to treat 19 patients with advanced transitional-cell carcinoma (TCC) of the urothelial tract. In the CMV group, the partial response rate was 45.5% and the mean response duration was 6.3 months. No complete response was obtained in our series. The median duration of survival was 15.8 and 8.3 months in responders and nonresponders, respectively. The toxic symptoms included one case of sepsis and three cases of renal toxicity. However, nausea and vomiting were experienced by most patients and required the administration of antiemetics. In the M-VAC group, the median duration of survival for responders was longer than that of nonresponders (greater than 10.2 vs 7.2 months), although the number of patients was too small for this difference to reach statistical significance. The toxic symptoms included one case of sepsis, two cases of renal toxicity, and nausea and vomiting in most patients. Bone metastasis in three patients did not respond to chemotherapy (CMV), a finding that is compatible with the results reported by other investigators. In summary, chemotherapy with the CMV or M-VAC regimen was effective in improving the response rate of patients. However, the duration of response was short, toxicity was severe in some cases, and the efficacy against bone lesions was poor. These problems must be solved to improve the outcome of patients with TCC following chemotherapy with the CMV or M-VAC regimens.

Treatment guideline of enuresis in Taiwan.

The treatment guideline of enuresis suggested by the study group of enuresis in Taiwan is reported. Medical consultation and treatment of enuresis are recommended at the age of 5 and 6 years respectively. Evaluation of the enuretic children includes history taking, physical examination and laboratory investigations. A checklist is provided for quick evaluation in busy clinics. Urinalysis, urine specific gravity and office ultrasonography are essential tests. An algorithm of treatment of monosymptomatic enuresis is constructed. The two main options of treatment are behavioral modification with alarm system and pharmacotherapy with desmopressin or imipramine. Imipramine is recommended as one of the treatment options because of its relative safety in Taiwan. However the potential toxicity and mortality of imipramine is highlighted and warned. The responses to treatment are evaluated after a period of treatment for 1 to 3 months. Further evaluation and individualized treatment is suggested for poor responders.

Impact of aging on rat urinary bladder fatigue.

PURPOSE: Little is known about the fatigability of the urinary bladder. In these experiments, we characterized contractile and bioenergetic changes in bladder fatigue and investigated the impact of aging on these changes. MATERIALS AND METHODS: Whole urinary bladders from 3-month-old (n = 17) and 24-month-old (n = 12) SD rats were isolated and individually mounted in organ baths. The bladders were electrostimulated repeatedly (50 volts, 32 Hz, 1 MS; every 2.5 minutes). The pressure generation, rate of pressure generation and the emptying ability (% volume emptied) of the isolated bladders were measured with each stimulation. After the 20th electrostimulation, the bladders were immediately stimulated with 500 microM bethanechol. Upon completion of their series of stimulations, some of the bladders were quickly frozen in liquid nitrogen. Tissue phosphocreatine and ATP content of the frozen bladders and a group (six 3-month-old and six 24-month-old rats) of fresh bladder tissues was determined using high performance liquid chromatography (HPLC). RESULTS: The results can be summarized as follows: (1) Pressure generation, rate of pressure generation and emptying ability were gradually reduced in both young and aged bladders as repeated stimulation proceeded. (2) The final bethanechol stimulation emptied the same intravesical volume as the 20th electrostimulation emptied (in both groups), indicating that bladder fatigue is due to a post-synaptic mechanism. (3) As compared to their own first responses, aged rats exhibited significantly greater rates of reduction in both pressure generation and emptying ability than did young rats. (4) Analysing fresh bladder tissues, the phosphocreatine and ATP concentration of the aged bladders were significantly less than those of the young bladders-13.2 +/- 2.0 and 1.2 +/- 0.3 nmol/mg. protein respectively in the aged bladders vs. 21.2 +/- 1.8 and 7.5 +/- 1.0 nmol/mg. protein respectively in the young bladders. After repeated stimulation, phosphocreatine and ATP concentration were reduced in both groups (1.4 +/- 0.3 and 0.43 +/- 0.1 nmol./mg. protein in the aged bladders, 7.5 +/- 1.4 and 4.1 +/- 0.5 nmol./mg. protein in the young bladders), with a greater degree of reduction in the aged bladders. CONCLUSION: These observations indicate that, in response to repeated electrostimulation, aged rat bladders became fatigued faster than young bladders. Decreased capability in energy production might be one contributing factor for faster fatiguability of the aged urinary bladders.

Effects of aging on mitochondrial enzyme activity of rat urinary bladder.

OBJECTIVES: Our previous study showed that aged rat bladders became fatigued faster than young bladders following repeated contraction induced by electrostimulation. One factor might be a lower energy-producing capability secondary to a decreased mitochondrial enzyme activity of the aged bladder. This study examined this possibility. MATERIALS AND METHODS: Mitochondria from 3- (n = 11) and 24-month-old (n = 10) Sprague-Dawley rats were isolated. Activities of the following enzymes were assayed: two key enzymes in the citric acid cycle, citrate synthase and malate dehydrogenase, and three enzymes in the respiratory chain reaction, NADH-cytochrome c reductase, succinate-cytochrome c reductase and cytochrome c oxidase. The concentration of phosphocreatine and ATP in the aged rat bladders and a separate group of young bladders (n = 12) was determined using high-performance liquid chromatography. RESULTS: (1) The aged bladders have a significantly lower level of phosphocreatine and ATP content than those of young bladders. (2) The activities of all five enzymes assayed were significantly lower in the aged bladders than in young bladders, especially for citrate synthase, which had only 46.8% of the activity of young bladders. CONCLUSIONS: Aging reduces the mitochondrial enzyme activity of the rat bladder resulting in a lower energy-production capability, which might explain some of the voiding dysfunctions found in the elderly.

Mannitol facilitates rabbit urinary bladder recovery from overdistension injury.

OBJECTIVES: To investigate the existence and functional significance of the enhanced lipid peroxidation in bladder overdistension injury and to explore the effect of mannitol, a free radical scavenger. METHODS: Overdistension of rabbit bladders was induced and maintained for 3 hours by infusing normal saline into the bladder while keeping the intravesical pressure at 30 cm H(2)O. The bladders were then emptied and decompressed. Intravenous 20% mannitol was initiated 5 minutes before decompressing the overdistension. Detrusor tissue was obtained from the following groups: control, at the end of the overdistension period, and 30 minutes, 2 hours, and 7 days after decompressing the bladder. The tissue level of adenosine triphosphate (ATP) and phosphocreatine (PCr) and the lipid peroxidation product malondialdehyde (MDA) was assayed. Detrusor contractility was assessed by the response of the detrusor strips to KCl and bethanechol. RESULTS: Decompressing the overdistended bladder led to a period of enhanced lipid peroxidation with an increase of MDA content from 225 to 384 pmol/mg protein 30 minutes after the decompression. Two hours later, the MDA content had recovered to the normal level. Mannitol abolished this period of enhanced lipid peroxidation. Overdistension impaired detrusor contractility and reduced the content of PCr (from 24.1 to 10.8 nmol/mg protein) and ATP (from 9.6 to 4.6 nmol/mg protein). Both detrusor contractility and the content of PCr and ATP further decreased 30 minutes after the decompression (PCr 5.4 nmol/mg, ATP 2.8 nmol/mg). They had recovered, but not fully, 7 days later. Mannitol prevented the further decrease in detrusor contractility and in the content of PCr and ATP during the initial decompression period (30 minutes after the decompression). In addition, the mannitol-treated group had quicker recovery in PCr and ATP levels, which returned to normal 7 days later. CONCLUSIONS: Decompressing an overdistended bladder leads to enhanced lipid peroxidation, which is associated with an additionally decreased energetic metabolism and a more impaired contractile function. Mannitol effectively prevents enhanced lipid peroxidation and facilitates functional recovery. These results show that reactive oxygen species play a significant role in bladder overdistension injury.

Concentration of bone marrow mononuclear cells using a programmable blood cell separator.

Bone marrow was collected from adult patients with various solid tumors who consented to participate in a study of myelo-ablative chemotherapy followed by autologous bone marrow rescue. Twenty marrow suspensions were processed by using standard Procedure 3 (PRO-3) for lymphocytapheresis without modification. A modified Procedure 1 (M-PRO-1) for plateletpheresis was employed for processing 34 marrow suspensions. For PRO-3, mononuclear cell (MNC) recovery was 68 +/- 22% of the starting marrow suspension (baseline), in a concentrate volume of 234 +/- 53 ml. MNC represented 59 +/- 27% of the total WBC count of the concentrate. The residual volume of RBC was 49 +/- 47 ml. For M-PRO-1, MNC recovery was 63 +/- 22% of the baseline in a concentrate volume of 200 +/- 8 ml. MNC comprised 94 +/- 7% of the total WBC count of the concentrate. RBC contamination was 7 +/- 3 ml. Hematopoietic recovery, defined as the post-transplant days when a sustained granulocyte count of 500/microL and a platelet count of 50,000/microL were achieved, was similar in the two groups and comparable to other reports utilizing other methods and equipment for bone marrow concentration. Personnel time was significantly reduced compared to other procedures for bone marrow concentration due to increased automation. Although there was no significant difference in MNC recovery between the two groups (P greater than 0.5), M-PRO-1 was clearly superior to PRO-3 because of the consistently high degree of purity of the MNC in the concentrate and minimal RBC contamination.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of orchiectomy on the alpha adrenergic contractile response of dog prostate.

PURPOSE: To investigate the effect of androgen deprivation on the alpha-adrenergic contractile response of the dog prostate using both in vitro and in vivo methods. MATERIALS AND METHODS: In vitro muscle bath study: One month after surgery, responses to KCl (120 mM.) and norepinephrine (10(-8) to 10(-3)M.) of prostatic tissue strips (of the same size) from castrated (n = 6) and sham-operated (n = 6) adult mongrel dogs were determined. In vivo study: Before and 1 month after surgery, the intraprostatic urethral pressure response to intravenous norepinephrine administration of 6 castrated and 5 sham-operated adult dogs was examined. RESULTS: (1) Before castration the serum level of testosterone was 1.24 +/- 0.2 ng./ml.; 1 month after castration, it had dropped to an undetectable level. (2) Histological examination of the prostates from castrated animals revealed profound atrophy of glandular tissue with a relatively increased stromal tissue component in each section. (3) In vitro study: The contractile responses to KCl and norepinephrine of individual prostate strips (same size) from castrated animals were significantly higher than control. However, if the response to norepinephrine was normalized to the response to KCl, there was no significant difference in response to norepinephrine between the 2 groups. In addition, the ED50 of the norepinephrine-stimulated contractile response was not changed by castration. (4) In vivo study: There was no significant change in intraprostatic urethral pressure response to intravenous norepinephrine administration after orchiectomy. CONCLUSIONS: The results of this study show that the sensitivity of the alpha-adrenergic contractile response of the dog prostate is not affected by androgen deprivation, nor is alpha-adrenergic contractile activity of the dog prostate regulated by androgen.

The subjective assessment and pressure-flow study of outcome of surgical treatment for patients with prostatism and high voiding pressure.

BACKGROUND: In 1992, the International Continence Society (ICS) began to conduct an international multicenter study to correlate the symptoms and urodynamics in patients with BPH. Our institute was invited to participate this ICS-BPH study, and the preliminary (phase I) results have revealed poor correlation between preoperative symptoms and parameters of the pressure-flow study. This phase II study continued the phase I ICS-BPH study to assess the changes of subjective symptoms and objective parameters of pressure-flow study before and after TURP. METHODS: Fifty-two patients with prostatism, aged from 56 to 80, were evaluated using the ICS-BPH questionnaire, free urine flow rate and pressure-flow study. According to the criteria of maximum urine flow rate (Qmax) 15 ml/sec and voiding intravesical pressure at Qmax (Pves at Qmax) 100 cm H2O, low flow-high pressure (LFHP) was proved in 20 patients (38%), high flow-high pressure (HFHP) in 22 (42%), low flow-low pressure (LFLP) in 3 (6%), and high flow-low pressure (HFLP) in 7 (14%). Transurethral resection of the prostate (TURP) was performed for 33 of 42 patients with high voiding pressure (LFHP and HFHP groups). RESULTS: The weight of the TURP specimen was 28 +/- 6.3 gm. Sixteen patients repeated the questionnaire and pressure-flow study 9.0 +/- 2.1 months after surgery. Both irritative and obstructive symptom scores decreased in 15 (94%) of the 16 patients (p < 0.001). The opening intravesical pressure (openPves) and Pves at Qmax improved from 136 +/- 34 and 124 +/- 30 cm H2O preoperatively to 89 +/- 25 and 94 +/- 22 cm H2O postoperatively respectively (p < 0.004). However, UFRmax, 16.7 +/- 6.0 ml/sec preoperatively and 19.3 +/- 6.4 postoperatively, showed no statistical difference. If the HFHP and LFHP groups were compared separately, the degree of improvement in symptomatology or parameters of pressure-flow study was similar, although changes in HFHP group appeared more evident. UFRmax in LFHP group changed significantly from 11.9 +/- 2.8 preoperatively to 22.1 +/- 6.7 ml/sec postoperatively. For the patients with high flow obstruction (HFHP group), although UFRmax did not increase after TURP, the symptom score, openPves and Pves at Qmax, decreased as much as the LFHP group did. CONCLUSIONS: Based on the analysis of the pressure flow study, TURP not only offers an advantage to the patient with classical obstruction (LFHP group), but also to patients with high flow obstruction (HFHP group). However, this does not suggest that a pressure-flow study should be performed routinely for a male with prostatism. It is advised only for patients with Qmax > 15 ml/sec but exhibiting typical symptoms.

In vitro simulation of thermotherapy for benign prostatic hyperplasia by Fourier transform infrared microspectroscopy combined with differential scanning calorimetry.

Thermo-dependent changes in the secondary structure of the epithelium and stroma of benign prostatic hyperplasia (BPH) were investigated by Fourier transform infrared (FT-IR) microspectroscopy combined with differential scanning calorimetry (DSC). This microscopic FT-IR/DSC system was used to simulate transurethral thermotherapy for BPH in vitro. The results indicate that thermal-induced conversion from an alpha helix to a beta structure was found in the epithelium and stroma of BPH. However, this thermal-induced conversion behavior in the stroma was less sensitive than that in the epithelium during thermal treatment. The different thermal response between the epithelium and stroma of BPH might be due to the different constitutions of the epithelium and stroma of BPH.

Renal angiomyolipoma--experience of 20 years in Taiwan.

OBJECTIVE: 32 cases of renal angiomyolipoma were presented. Diagnosis, treatment and prognosis of the 32 cases were discussed. MATERIAL AND METHODS: A total of 32 cases of renal angiomyolipoma treated at the Veterans General Hospital-Taipei between 1974 and 1994 were retrospectively reviewed. Follow-up periods ranged from 2 to 108 months (mean 43.4). RESULTS: Of the 32 cases, 26 were female, 28 were unilateral lesions and 2 were associated with tuberous sclerosis. The tumor size averaged 6.73 cm (range 2-25). The mean age was 48.3 years. There was a typical image finding in 87.5% of the 28 unilateral tumors. Tumors larger than 4 cm had a greater incidence of symptoms (90%) and a higher nephrectomy rate (18/22). 30 cases underwent surgery including 22 nephrectomy, 1 partial nephrectomy and 7 enucleation. The nephrectomy rate decreased from 90% (9/10) to 59.1% (13/22) after 1985. Only 1 patient had a contralateral recurrence 26 months after surgery. Two cases had unusual presentations, which were perirenal capsule invasion and renal vein extension, respectively. CONCLUSIONS: Our experience with angiomyolipoma in the past 20 years showed that the advancement of imaging technology has much improved the diagnosis of this tumor. A correct diagnosis is possible in most cases before surgery. The nephrectomy rate has markedly decreased in recent years. Every effort should be made to preserve renal tissue in the treatment of this benign tumor.

Effects of outlet obstruction and its reversal on mitochondrial enzyme activity in rabbit urinary bladders.

PURPOSE: This study investigated the effects of outlet obstruction and its reversal on mitochondrial enzyme activity in the rabbit urinary bladder. MATERIALS AND METHODS: We induced mild bladder outlet obstruction in male New Zealand White rabbits. Following two weeks of obstruction, one group of animals (n = 6) was sacrificed, while outlet obstruction was relieved in three additional groups of animals, which were sacrificed one (n = 5), two (n = 5) and four (n = 5) weeks after relieving the obstruction. Seven sham operated rabbits served as controls. We extracted mitochondria from fresh detrusor and assayed activities of key mitochondrial enzymes in the citric acid cycle, citrate synthase and malate dehydrogenase, as well as those in the electron transport chain, succinate cytochrome c reductase, NADH-cytochrome c reductase and cytochrome c oxidase. With high performance liquid chromatography (HPLC) we determined the tissue content of phosphocreatine and the adenine nucleotides (ATP, ADP and AMP), which was used for calculating energy charge. Responses of detrusor strips to 500 microM bethanechol and 120 mM KCl provided the assessment of detrusor contractility. RESULTS: Contractile response of the detrusor strips to bethanechol stimulation was significantly reduced by outlet obstruction, nevertheless, it recovered gradually toward the control level after the relief of outlet obstruction. Outlet obstruction reduced the detrusor content of phosphocreatine, ATP and energy charge. After relieving the obstruction, however, these recovered gradually, reaching control levels 4 weeks later. The activities of all assayed enzymes were reduced by two weeks of outlet obstruction. Relieving the obstruction restored enzyme activity gradually but at different rates for different enzymes. Activities of the citric acid cycle enzymes citrate synthase and malate dehydrogenase recovered and were similar to control levels four weeks after relief of the obstruction. Of the enzymes in the electron transport chain, NADH cytochrome reductase activity recovered most quickly by one week after relief of the obstruction. The activity of cytochrome c oxidase improved more slowly, but 4 weeks after relieving the obstruction it, also, was restored and was similar to the control level. Succinate cytochrome reductase activity remained lower than the control over the entire four weeks of recovery. CONCLUSIONS: The close association between mitochondrial enzyme activity, energy metabolism and contractility of the detrusor indicates the important role of mitochondrial enzyme damage in decreasing energy production and impairing contractile function of the urinary bladders following outlet obstruction. Our findings also show that various mitochondrial enzymes exhibit different susceptibilities and reversibilities to pathological stress.

Pharmacological responses of rabbit urinary bladder after subtotal cystectomy.

Partial cystectomy is used clinically in specific circumstances. There have been some reports indicating that the bladder following subtotal cystectomy can regenerate to a certain degree. The present study investigates the physiology and pharmacology of bladder regeneration at eight weeks after resection of a major part of the bladder body in rabbits. The following studies were performed on control and cystectomy bladders: 1) in vivo cystometry (prior to and four weeks after the operation, and before the sacrifice at eight weeks); 2) sequential muscle strip study (the strips were obtained by dividing bladder transversely into upper body, lower body, mid-bladder, upper base and lower base); and 3) in vitro whole bladder studies. The results can be summarized as follows: 1) grossly there was no regeneration of the bladder body; the cystometric capacity was increased slowly after the operation primarily due to increased size and capacity of the bladder base. 2) The contractile response of the subtotal cystectomized bladder body to field stimulation and bethanechol stimulation was less than the response of normal bladder body. 3) The contractile response to epinephrine showed that the ratio of alpha/beta adrenergic response was much greater in the cystectomy bladder than in the normal bladder. 4) In the whole bladder study, the intravesical pressure response to field stimulation was about the same in both groups, the response to bethanechol was less for cystectomized bladder, and the response to methoxamine was greater for the cystectomized bladder. 5) The ability of cystectomy bladder to empty in response to both field stimulation and bethanechol was impaired whereas the control bladder fully emptied to both field stimulation and bethanechol. In conclusion, over the eight week period following subtotal cystectomy the capacity increased via distention (and hypertrophy) of the bladder base area as opposed to regeneration of the bladder body.

Blood flow of the urinary bladder: effects of outlet obstruction and correlation with bioenergetic metabolism.

This study investigated the effects of outlet obstruction on blood flow and high energy phosphates content in the rabbit urinary bladder. Mild bladder outlet obstruction was induced by placing a silicon ring (diameter 7 mm) around the bladder neck of each male New Zealand White rabbit (n = 7). Before and immediately after inducing obstruction, and 2 weeks later, the bladders were emptied and regional blood flow measured using laser Doppler flowmetry (LASERFLO BPM2, Vasamedics Inc., St. Paul, Minnesota). Six different areas of each bladder were measured, and the average blood flow calculated for each rabbit. Then, the animals were sacrificed, the bladder excised, and the tissue content of high energy phosphates determined by high performance liquid chromatography (HPLC). Six normal male New Zealand White rabbits served as controls. The results can be summarized as follows: (1) Before surgery, bladder blood flow was similar in all animals (16.3 ml/min/100 g); positioning the silicon ring around the bladder neck did not affect blood perfusion, two weeks after the induction of outlet obstruction, bladder blood flow was significantly decreased (4.9 ml/min/100 g). (2) There was no significant difference between control and obstructed bladders in NAD, AMP, or ADP content. However, the obstructed bladders contained significantly less phosphocreatine (12.0 vs 21.9 nmol/mg protein) and ATP (4.0 vs. 6.1 nmol/mg protein) than control bladders. In summary, this study showed that urinary bladder blood flow was reduced by outlet obstruction, and the reduction in blood flow was associated with decreased tissue high energy phosphates content.(ABSTRACT TRUNCATED AT 250 WORDS)

Morphological and morphometric analysis of human detrusor mitochondria with urodynamic correlation after partial bladder outlet obstruction.

PURPOSE: We correlated ultrastructural changes in mitochondria in the human detrusor with the severity of partial bladder outlet obstruction on urodynamics. MATERIALS AND METHODS: We recruited into the study 52 men with and without bladder outlet obstruction symptoms. The severity of partial bladder outlet obstruction was determined by pressure flow study. Random detrusor biopsy specimens obtained by cystoscopy were fixed immediately and processed for transmission electron microscopic observation. Random areas were photographed for further morphological and morphometric analysis using mitochondrial damage score and stereological principles. RESULTS: Mitochondrial damage score and mean mitochondrial volume strongly correlated with the urodynamic severity of partial bladder outlet obstruction, while mitochondrial volume density, surface density of the mitochondrial outer membrane and number of mitochondria per unit of cytoplasm area did not significantly correlate with severity. CONCLUSIONS: Detrusor mitochondrial swelling and structural destruction increased with the severity of partial bladder outlet obstruction. These changes may be associated with impaired mitochondrial function and oxidative metabolism after partial bladder outlet obstruction. Detrusor mitochondrial damage may explain voiding dysfunction after partial bladder outlet obstruction develops.

Mitochondrial DNA deletion of the human detrusor after partial bladder outlet obstruction-correlation with urodynamic analysis.

OBJECTIVES: To investigate mitochondrial DNA (mtDNA) mutations in human detrusor after partial bladder outlet obstruction (BOO) and correlate the findings with the results of urodynamic studies. METHODS: Sixty-two male patients with and without BOO were recruited and assessed by the International Prostate Symptom Score, a quality-of-life assessment index, and sonography. The severity of partial BOO was determined by pressure-flow study with an International Continence Society (ICS) nomogram. Random detrusor biopsies obtained cystoscopically were analyzed by polymerase chain reaction (PCR) techniques to detect possible mtDNA deletions. Primer-shift PCR and DNA sequencing were then performed to characterize specific mtDNA deletions. A semiquantitative PCR method was used to determine the proportion of the deleted mtDNA in detrusor. Finally, the mtDNA deletion and the urodynamic results were compared statistically. RESULTS: A 4977-bp mtDNA deletion was identified in the human detrusor. Its incidence and proportion were found to increase after partial BOO (P = 0.005 and 0.012, respectively). The incidence of the mtDNA deletion was 4.2% (1 of 24) in the unobstructed group, 27.8% (5 of 18) in the equivocal group, and 40% (8 of 20) in the obstructed group. The mean proportion of the 4977-bp deleted mtDNA was 23.7 and 12.7 times higher in the obstructed and equivocal groups, respectively, compared with that of the unobstructed group. CONCLUSIONS: We found mtDNA with the 4977-bp deletion in human detrusor and an increase of this deletion after partial BOO. This molecular change might account for the previous observations of mitochondrial functional impairment and voiding dysfunction after partial BOO.