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de Lamirande E, Leduc BE, Iwasaki A, Hassouna M, Gagnon C. Increased reactive oxygen species formation in semen of patients with spinal cord injury. Fertil Steril 1995; 63:637-42. [PMID: 7851599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVES To evaluate reactive oxygen species production of semen samples and Percoll-washed spermatozoa from men with spinal cord injuries and to determine if there is a relationship between this reactive oxygen species production and sperm motility. PARTICIPANTS Semen samples from healthy volunteers and infertile patients were collected by masturbation. INTERVENTIONS Semen samples from men with a spinal cord injury were obtained by electroejaculation or by masturbation after treatment with physostigmine. MAIN OUTCOME MEASUREMENTS Motility was measured using the CellSoft computer-assisted analysis system (Cryo Resources Ltd., Montgomery, NY). Luminol-amplified chemiluminescence was used to measure reactive oxygen species production. RESULTS Semen samples and Percoll-washed spermatozoa from men with a spinal cord injury produced reactive oxygen species at much higher frequency and levels than equivalent preparations from infertile men or healthy volunteers. There was an inverse relationship between the percentage of motility and reactive oxygen species production in Percoll-washed spermatozoa from men with a spinal cord injury. CONCLUSION Semen samples and Percoll-washed spermatozoa from men with spinal cord injury produce high levels of reactive oxygen species that may be related to the low sperm motility and infertility observed in these men.
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de Lamirande E, Leduc BE, Iwasaki A, Hassouna M, Gagnon C. Increased reactive oxygen species formation in semen of patients with spinal cord injury**Supported by a grant from the Medical Research Council of Canada, Ottawa, Ontario, Canada to C.G.††Presented in part at the 1992 Annual Meeting of the American Urological Association, Washington, D.C., May 10 to 14, 1992. Fertil Steril 1995. [DOI: 10.1016/s0015-0282(16)57438-x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Li JS, Hassouna M, Sawan M, Duval F, Elhilali MM. Long-term effect of sphincteric fatigue during bladder neurostimulation. J Urol 1995; 153:238-42. [PMID: 7966780 DOI: 10.1097/00005392-199501000-00084] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Commercially available stimulators lack several features, including multiple channel capability and flexible stimulation parameters. These factors limit clinical application. A new computerized electrical stimulator system was developed by our team and evaluated for its efficacy in bladder evacuation in an animal model after spinal cord transection. The system can generate a wide range of stimulation characteristics and has the feature of being a programmable multichannel pacemaker. It has enabled us to induce a reversible fatigue to the external sphincter that results in proper bladder emptying on stimulation. Using this new bladder pacemaker, 8 dogs were studied. We applied the concept of fatiguing of the external sphincter via the pudendal nerve to avoid rhizotomy. We determined the optimal stimulation parameters that can reliably empty the dog's bladder for the duration of the experiment, which lasted for 8 months. The new computerized electrical stimulation system achieved the objective of reducing bladder outlet resistance without the need for sacral rhizotomy.
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Hirakawa S, Hassouna M, Deleon R, Elhilali MM. The role of combined pelvic floor stimulation and biofeedback in female urinary incontinence: early experience. THE CANADIAN JOURNAL OF UROLOGY 1994; 1:72-7. [PMID: 12834544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
A series of 109 female patients with urinary incontinence were treated by pelvic floor stimulation and biofeedback. Eighty-one patients received the full course of treatment and 28 patients dropped out. Among the 81 patients who completed the treatment, the improvement and cure rates (completely dry) shortly after treatment were 70.4% and 12.3%, respectively. The improvement and cure rates for more than one year after treatment were 47.6% and 14.3% respectively. Seven patients returned for further pelvic floor stimulation and biofeedback and only three patients underwent bladder neck suspension operations after completing treatment. Of the patients who dropped out, 53.6% had shown improvement with pelvic floor stimulation and biofeedback. Side effects were rare with three patients complaining of abdominal pain. These findings suggest that pelvic floor stimulation and biofeedback are useful, safe and conservative treatment modalities for female patients with urinary incontinence.
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Abstract
The dog provides an important model to study the effect of neural stimulation of different parts of the central and peripheral nervous systems. A multitude of experiments on neurostimulation and neuromodulation to ensure bladder evacuation have been conducted on dogs. The present article reviews the most prominent contributions in the English literature related to neurostimulation using the dog as an experimental model. The various modes of stimulation using dogs as a model and the rationale for their use as well as their shortcomings will be examined. The prominent anatomic features in the neural control of the bladder and the technical aspects involved in neurostimulation of the canine bladder will be reviewed.
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Selmy G, Hassouna M, Bégin LR, Coolsaet BL, Elhilali M. Effect of balloon dilation of ureter on upper tract dynamics and ureteral wall morphology. J Endourol 1993; 7:211-9. [PMID: 8358417 DOI: 10.1089/end.1993.7.211] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Sixteen male Yucatan minipigs underwent balloon dilation of the right ureterovesical junction (UVJ) and lower ureter to twice its normal caliber. With the bladder open, bilateral upper tract dynamics measurements under different perfusion rates (0.5, 2, and 4 ml/min) were recorded predilation, immediately after dilation, and 1, 2, 3, 4, and 6 weeks after dilation. Immediate and late antegrade nephrostograms, suprapubic cystograms, and right antegrade nephrostograms (oblique view) were taken. In the chronic experiment, no difference in renal pelvic pressure (Ppvs) was detectable between the control and dilated sides immediately after dilation. Only at 4 ml/min was there a statistically significant increase in the Ppvs of the dilated ureter 1 week after dilation when compared with the controls. At 2 weeks, this obstructive change had disappeared. At 3, 4, and 6 weeks, Ppvs of the dilated ureter declined progressively in comparison with the control side, but the difference was not statistically significant. At 6 weeks, Ppvs of the dilated ureter decreased significantly compared with predilation readings only at 4 ml/min. Immediate antegrade radiologic evaluation revealed that 69% of the experimental animals had no extravasation, while 31% showed variable degrees of extravasation, which disappeared completely on late antegrade nephrostograms (6 weeks). Grade 2 reflux occurred in 33% of the experimental animals at 1 week and had disappeared at 6 weeks. Histologic examinations at 1, 2, and 3 weeks revealed a nonhomogeneous pattern of ureteral damage, ranging from total rupture to much less dramatic injury.(ABSTRACT TRUNCATED AT 250 WORDS)
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Sawan M, Duval F, Li JS, Hassouna M, Elhilali MM. A new bladder stimulator--hand-held controller and miniaturized implant: preliminary results in dogs. Biomed Instrum Technol 1993; 27:143-9. [PMID: 8453422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A new urinary-tract stimulator that is intended to restore normal bladder function to patients who have spinal-cord injuries is described. The system is composed of two principal parts. The first, which is external, consists of a hand-held device based on an inductive-coupling technique. This controller incorporates all the circuitry necessary to transmit data transdermally. The second, a fully programmable implantable device, includes a complementary metal oxide semiconductor gate-array integrated circuit controlling eight monopolar (or four bipolar) stimulation channels. To protect the tissues and the device, three different biocompatible polymers encapsulate the implant. In the experimental phase, the authors investigated the effect of early electrical stimulation of the bladder during the spinal-shock phase in paraplegic dogs. In addition, using the stimulator, they localized the parameters of stimulation that give the best results in terms of effective bladder pressure and voiding a high volume of urine.
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Sawan M, Duval F, Hassouna M, Li JS, Elhilali MM. A transcutaneous implantable bladder controller. Neurourol Urodyn 1993; 12:281-4. [PMID: 8330052 DOI: 10.1002/nau.1930120313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We describe a computerized experimental system to investigate the effect of early electrical stimulation of the bladder during the spinal shock phase in paraplegic dogs. This system is composed of two main devices; an external part (or controller) based on a portable microcomputer, and a versatile implant (internal) based on a multichannel CMOS microstimulator. Using a new operative technique, this system enabled us to obtain many favorable results.
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Hassouna M, Li JS, Sawan M, Duval F, Latt R, Elhilali MM. Effect of early bladder stimulation on spinal shock: experimental approach. Urology 1992; 40:563-73. [PMID: 1466114 DOI: 10.1016/0090-4295(92)90418-v] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The period of spinal shock which frequently follows spinal cord injury is associated with bladder areflexia and urinary retention. We studied the effect of early bladder electric stimulation on detrusor activity during the spinal shock phase in the dog. The animals had a spinal cord section at T10 vertebra, and their bladder management was assigned to one of the three following groups: intermittent catheterization, indwelling catheterization, and electric bladder stimulation. The parameters for evaluating each treatment included: blood chemistry, and radiographic and urodynamic tests. The most important finding was the early return of detrusor activity in the group of animals treated by early electric stimulation of the bladder.
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Li JS, Hassouna M, Sawan M, Duval F, Elhilali MM. Electrical stimulation induced sphincter fatigue during voiding. J Urol 1992; 148:949-52. [PMID: 1512865 DOI: 10.1016/s0022-5347(17)36784-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The stimulation of the sacral nerves to induce voiding is often associated with simultaneous contraction of the striated sphincter rendering micturition difficult or impossible. Rhizotomy of some sacral nerves was found to be necessary to facilitate voiding with stimulation. An main objective in the present experiment was to evaluate the feasibility of achieving the same result using electrical stimulation to fatigue the sphincter. In order to compare the effect of rhizotomy and fatiguing striated sphincter, the bladder outlet resistance was measured. S2 nerves were stimulated with 3 V, 35 Hz and 100 microseconds duration for 5 to 10 sec. Following S2 nerves stimulation the pudendal nerve was stimulated till we obtained sphincteric fatigue. The optimal parameter to induce sphincter fatigue were 3 V, 100-500 Hz and 100 microseconds. for 15-20 sec. The combined pressure-flow studies showed that fatiguing the sphincter via the pudendal nerve using these parameters was as good as cutting it in achieving bladder emptying with stimulation.
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61
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Li JS, Hassouna M, Sawan M, Duval F, Latt R, Carter K, Collier B, Elhilali MM. Role of electric stimulation in bladder evacuation following spinal cord transection. J Urol 1992; 147:1429-34. [PMID: 1569699 DOI: 10.1016/s0022-5347(17)37587-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Neural stimulation is potentially a valuable therapeutic tool in the treatment of neurogenic bladder with detrusor areflexia. We studied 20 dogs in different groups, up to eight months, and compared the effect of electric stimulation with intermittent catheterization, specially during spinal shock phase. We found that early stimulation hastened the return of detrusor activity. When stimulation was delayed, the bladder could still regain its activity, and when the pace-maker was turned off, the detrusor activity was gradually decreased. Neurostimulation can completely empty bladder up to eight months. The lowest A.Ch. content in detrusor muscle was found in intermittent catheterization group and in this group the detrusor strips showed marked supersensitivity to urecholine stimulation than the bladders managed by electric stimulation. Also, we found that electric stimulation reduced the complications caused by intermittent catheterization and protected kidney function.
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62
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Hassouna M, Elgammal M, Gafir S, Stein L, Elhilali M. Digital subtraction cavernosography: method to detect venous leakage. Urology 1991; 38:577-81. [PMID: 1720908 DOI: 10.1016/0090-4295(91)80184-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Cavernosography has become an important diagnostic test for detecting venous leakage as a cause of vasculogenic impotence. Digital subtraction cavernosography (DSC) was carried out on 21 patients with a history of venous leakage resulting in impotence. The DSC technique was compared to conventional cineradiography. Major venous leaks were easily identified in 16 patients. DSC was able to detect minor leaks missed by cineradiography in 2 patients. DSC seems to be a reliable technique that is easy to perform. It should be done in conjunction with pharmacologically induced erection.
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63
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Fouda A, Hassouna M, Beddoe E, Kalogeropoulos D, Binik YM, Elhilali MM. Priapism: an avoidable complication of pharmacologically induced erection. J Urol 1989; 142:995-7. [PMID: 2795759 DOI: 10.1016/s0022-5347(17)38965-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Priapism is an alarming complication during treatment of erectile dysfunction with vasoactive drugs, particularly papaverine alone or in combination with phentolamine mesylate. An investigational protocol was designed to identify patients who are more susceptible to priapism after intracavernous injection of papaverine alone or with phentolamine. The protocol was applied in 331 men with impotence of various etiology. The association of a positive response to visual sexual stimulation and penile brachial index of more than 0.8 represented a higher risk for post-injection priapism. We were able to reduce the incidence of this compliance to 1% in the last 101 patients.
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64
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Ali-Shtayeh MS, Arda HM, Hassouna M, Shaheen SF. Keratinophilic fungi on sheep hairs from the West Bank of Jordan. Mycopathologia 1989; 106:95-101. [PMID: 2797114 DOI: 10.1007/bf00437087] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The mycoflora of the hair in 285 sheep from the West Bank of Jordan was analysed and the frequency of occurrence and the relative importance value for different fungal species found were calculated. Ninety six species which belong to 36 genera were isolated. Forty one of these species were either well-known agents of animal and human mycoses (Trichophyton verrucosum, T. mentagrophytes, Microsporum nanum, M. canis, and others), or have been isolated from human and animal lesions (Arthroderma cuniculi, A. curreyi, Chrysosporium tropicum, Acremonium kiliense, Aphanoascus fulvuscens, Aspergillus versicolor, Paecilomyces lilacinus, Scopulariopsis brevicaulis, and others). These pathogenic fungi comprised 75.4% of all fungi recovered from the hair of sheep. This animal seems to represent an adequate reservoir for several dermatophytes and several potentially pathogenic fungi.
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65
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el Rifaei A, Hassouna M, Fouda A, Latt R, Sawan M, Duval F, Elhilali MM. The effect of early bladder stimulation on spinal shock: a preliminary report. J Urol 1989; 141:1010-3. [PMID: 2784509 DOI: 10.1016/s0022-5347(17)41087-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The period of spinal shock which frequently follows spinal cord injury is associated with bladder areflexia and urinary retention. We studied the effect of early bladder electric stimulation on detrusor activity during the spinal shock phase in the dog. The animals had a spinal cord section at T10 vertebra and their bladder management was assigned to one of the three following groups: intermittent catheterization, indwelling catheterization and electric bladder stimulation. The parameters for evaluating each treatment included: blood chemistry, radiographic and urodynamic tests. The salient feature was the early return of detrusor activity in the group of animals treated by early electric stimulation of the bladder.
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66
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Meyer S, Hassouna M, Mokhless I, Coolsaet BLRA, Elhilali MM, Elbadawi A. Ultrastructural changes in the obstructed pig detrusor: A preliminary report. Neurourol Urodyn 1989. [DOI: 10.1002/nau.1930080206] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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67
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Ali-Shtayeh MS, Arda HM, Hassouna M, Shaheen SF. Keratinophilic fungi on the hair of goats from the West Bank of Jordan. Mycopathologia 1988; 104:103-8. [PMID: 3221912 DOI: 10.1007/bf00436935] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The mycoflora of the hair in 178 goats from the West Bank of Jordan was analysed and the frequency of occurrence and the relative importance value for the different keratinophilic fungi found were calculated. One hundred and seven species which belong to 38 genera were isolated. Thirty six of these species were either well recognised agents of mycoses (Trichophyton mentagrophytes, T. verrucosum, and M. nanum), or have been frequently isolated from human and animal lesions (Arthroderma spp., Acremonium kiliense, Alternaria alternata, Aspergillus flavus, Cladosporium carionii, and several other species). These potentially pathogenic fungal species comprised 66.9% of all keratinophilic fungi found on the hair of goats. The role of this animal as a reservoir for dermatophytes and other potentially pathogenic fungi is discussed.
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Ali-Shtayeh MS, Arda HM, Hassouna M, Shaheen SF. Keratinophilic fungi on the hair of cows, donkeys, rabbits, cats, and dogs from the West Bank of Jordan. Mycopathologia 1988; 104:109-21. [PMID: 3221913 DOI: 10.1007/bf00436936] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The mycoflora of hair of 111 cows, donkeys, rabbits, cats, and dogs were analysed and the frequency of occurrence and the relative importance value of the different fungal species isolated were calculated. Total numbers of species 56, 45, 48, 23, and 11 were recovered from cows, donkeys, rabbits, cats, and dogs respectively. The majority of the keratinophilic fungi isolated were either well-known mycotic agents or have been recovered from various animal and human lesions. These comprised 87.8%, 66.7%, 61.4%, 59.3%, and 55.2% of the hair mycoflora in cats, dogs, rabbits, cows, and donkeys respectively. Seven species of dermatophytes were isolated: Trichophyton mentagrophytes, T. verrucosum, Microsporum gypseum, M. nanum, T. ajelloi, and M. canis. Cats harboured the largest number of dermatophytes (5 species), followed by cows (4 spp), rabbits (3 spp), and donkeys and dogs (1 sp). The role of these animals in the persistence and transmission of pathogenic fungi is discussed.
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Gotoh M, Kondo A, Hassouna M, Elhilali MM. Effects of verapamil and sodium nitroprusside on acetylcholine-induced contraction of the rabbit detrusor muscle. UROLOGICAL RESEARCH 1987; 15:261-5. [PMID: 3686754 DOI: 10.1007/bf00258192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Effects of extracellular and intracellular Ca2+ on acetylcholine-induced contraction of the bladder detrusor muscle were studied in vitro, utilizing two types of Ca2+ antagonists of different mechanisms of action; verapamil and sodium nitroprusside (NP). Acetylcholine (10(-8) to 10(-2) M) caused dose-dependent contractions of the detrusor muscle strips. Pretreatment of the strips with verapamil (10(-7), 10(-6) M) significantly inhibited the acetylcholine-induced contraction in a dose-dependent manner, whereas NP (10(-7) to 10(-5) M) failed so suppress the contraction. The contraction of the strips once elicited by acetylcholine (10(-6) M) could be completely relaxed by verapamil (10(-5) M) addition, but only incompletely by NP (10(-5), 10(-4) M). In Ca2+-free solution containing 0.01 mM EGTA, replenishment of Ca2+ (2.5 mM) to the medium caused contractions of the strips. Addition of acetylcholine (10(-6) M) to the medium enhanced the Ca2+-induced contraction, which was significantly inhibited by pretreatment with verapamil (10(-6) M), but not affected by NP (10(-6) M). In Ca2+-free medium containing 0.1 mM EGTA, acetylcholine caused a slight degree of tension increase of the strips in a dose-dependent fashion, at higher concentrations exceeding 10(-6) M. These results suggest that the detrusor muscle contraction induced by acetylcholine is mostly dependent of extracellular Ca2+ influx both in its initiation and maintenance. It is also supposed, however, that intracellular Ca2+ fractions will partly participate in the acetylcholine-induced contraction and possibly in its maintenance.
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Mokhless IA, Kiruluta GH, Seemayer TA, Homsy YL, Hassouna M, Coolsaet BL, Elhilali MM. The Evolution of Artificial Sphincter Cuff in Growing Animals. J Urol 1987. [DOI: 10.1016/s0022-5347(17)76231-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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71
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Mokhless IA, Kaplan BS, Lisbona R, Homsy YL, Hassouna M, Fouda A, Coolsaet BR, Kiruluta GH. The Effect of Infravesical Obstruction on Renal Function. J Urol 1987. [DOI: 10.1016/s0022-5347(17)76023-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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72
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Gotoh M, Hassouna M, Mokhless I, Elhilali MM. Intravesical instillation of a calcium entry blocker and its effects on detrusor contractility: in vitro and vivo experiments. J Urol 1986; 135:1304-7. [PMID: 2423712 DOI: 10.1016/s0022-5347(17)46080-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The effects of intravesical instillation of a Ca2+ entry blocker (verapamil) on the contractility of the bladder detrusor muscle of the rabbit were investigated in vitro and in vivo. In in vitro experiments, using whole bladder preparations, spontaneous contractile activity and contraction induced by direct electric stimulation or acetylcholine were monitored. Both activities were inhibited in a time-dependent manner after the intravesical instillation of 7.5 mg. verapamil. The amplitude of spontaneous contraction 90 minutes after the instillation, was reduced to 10 per cent of control (before the instillation), and the response to electric stimulation and acetylcholine were inhibited to 16 per cent and 38 per cent of controls respectively. The detrusor contractility was still inhibited two hours after the removal of verapamil from the bladder. This inhibition of the detrusor contractility after removal of verapamil was completely reversed by adding four mM Ca2+ intravesically. During in vivo experiments, the changes of intravesical pressure elicited by pelvic nerve stimulation and the systemic arterial pressure were monitored. Sixty minutes after the intravesical instillation of 10 mg. verapamil, the rise of the intravesical pressure following the pelvic nerve stimulation was inhibited to 18 per cent of control, while the systemic arterial pressure was not affected. It is suggested that the intravesical instillation of verapamil can inhibit detrusor contractility without affecting cardiovascular status.
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Hassouna M, Nishizawa O, Miyagawa I, Toguri A, Gotoh M, Elhilali M. Role of calcium ion antagonists of the bladder detrusor muscle: in vitro and in vivo study. J Urol 1986; 135:1327-31. [PMID: 2423715 DOI: 10.1016/s0022-5347(17)46085-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Calcium (Ca2+) ions play an important role in the contractility of the detrusor. Most of the neurotransmitters and modulators act on the detrusor through altering the final intracellular concentration of Ca2+. We studied three commonly used Ca2+ antagonists on their effect of detrusor contractility in vitro: verapamil, nifedipine and segontin. All three inhibited the detrusor-induced contraction in a dose-dependent fashion. Verapamil showed noncompetitive inhibition. Segontin showed a competitive inhibition on both phasic and tonic contractions of the detrusor strips. Nifedipine selectively inhibited the phasic contraction noncompetitively but competitively suppressed the tonic contraction. The in vivo application of verapamil on the bladder of rabbits with multiple-sclerosis-like disease showed a significant increase in bladder capacity. The study shows the possibility of the potential use of Ca2+-antagonist to suppress the problem of bladder instability.
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Elhilali MM, Hassouna M, Abdel-Hakim A, Teijeira J. Urethral stricture following cardiovascular surgery: role of urethral ischemia. J Urol 1986; 135:275-7. [PMID: 3944857 DOI: 10.1016/s0022-5347(17)45608-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The incidence of urethral stricture has been surprisingly high following cardiovascular surgery in the last few years. We conducted a prospective study on 68 male patients undergoing cardiovascular surgery to determine the main factor(s) responsible for the development of urethral stricture. The penile-brachial pressure index was checked by strain gauge plethysmography. We found that urethral strictures developed in 15 patients (22 per cent) within an average of 3 months after cardiovascular surgery. Of these patients 13 had a penile-brachial index of 0.6 or less and complained of erectile impotence. A latex type of catheter was used in 11 and a silicone catheter in 4 of these 15 patients for urinary drainage. We conclude that urethral ischemia has an important role in the development of stricture, particularly when a latex urethral catheter is used for drainage. We recommend that a vascular penile study should be done in patients with erectile impotence undergoing an open heart operation, and that serious consideration should be given to the use of a cystocatheter diversion the night before the operation in those with a penile-brachial index less than 0.6. We strongly recommend the use of a silicone catheter in all other patients undergoing open heart surgery with hypothermia.
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Gotoh M, Hassouna M, Elhilali MM. The mode of action of prostaglandin E2, F2 alpha and prostacyclin on vesicourethral smooth muscle. J Urol 1986; 135:431-7. [PMID: 3511296 DOI: 10.1016/s0022-5347(17)45659-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Interactions of prostaglandin E2 (PGE2), F2 alpha (PGF2 alpha) and prostacyclin (PGI2) with Ca2+ on the isometric contraction of rabbit detrusor muscle strips were studied using two types of Ca2+ antagonists of different mechanisms of action: verapamil and sodium nitroprusside (NP). The effects of PGI2 on vesicourethral smooth muscle and their relationship with cholinergic, adrenergic receptors and nervous activity were also investigated. PGE2 and F2 alpha (3 X 10(-8) to 3 X 10(-5) M) caused dose-dependent contraction of the strips. Pretreatment of the strips with verapamil (10(-7) to 10(-5)M) significantly inhibited PGs-induced contraction in a dose-dependent manner, whereas NP(10(-7) to 10(-5)M) failed to suppress the contraction. Relaxation of the preparations once contracted by PGE2 and F2 alpha (3 X 10(-6)M) was induced completely by addition of verapamil (10(-5)M), and incompletely by NP(10(-5) to 10(-3)M). Washing of the strips with Ca2+-free solution containing 0.01 mM EGTA completely eliminated spontaneous activity and diminished basal tension, but replenishment of Ca2+ (0.5 to 10 mM) to the medium caused dose-related contraction and spontaneous activity of the strips. Addition of PGE2 and F2 alpha to the Ca2+-free medium enhanced Ca2+-induced contraction and spontaneous activity during Ca2+ replenishment, which were significantly inhibited by pretreatment with verapamil (10(-7) to 10(-5)M) in a dose-dependent manner, but not affected by NP (10(-7) to 10(-5)M). In Ca2+-free medium containing 0.1 mM EGTA, PGE2 and F2 alpha caused a slight degree of tension increase of the strips dose-dependently at the higher concentration exceeding 3 X 10(-6)M. PGI2 (10(-9) to 3 X 10(-4)M) caused dose-dependent contraction of the strips from the bladder body, base and the urethra. The contractile action of PGI2 was greatest on the bladder body, less on the base and minimal on the urethra. The effect of PGI2 was less potent than those of PGE2 and F2 alpha. The PGI2-induced contraction was slow in onset, short lasting, and not affected by pretreatment with phentolamine, propranolol, atropine, hexamethonium, hemicholinium-3 and tetrodotoxin. The interactions of PGI2 with Ca2+ were similar to those of PGE2 and F2 alpha.(ABSTRACT TRUNCATED AT 400 WORDS)
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Hassouna M, Lebel M, Abdel-Rahman M, Elhilali M. Evoked potential of the sacral arc reflex: Technical aspects. Neurourol Urodyn 1986. [DOI: 10.1002/nau.1930050605] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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77
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Abdel-Hakim A, Hassouna M, Teijeira J, Elhilali M. Role of urethral ischemia in the development of urethral strictures after cardiovascular surgery: a preliminary report. J Urol 1984; 131:1077-9. [PMID: 6726905 DOI: 10.1016/s0022-5347(17)50813-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A high incidence of urethral stricture was noted following cardiovascular surgery. In an attempt to elucidate factors predisposing to the occurrence of urethral stricture, we studied the penile blood flow in 7 patients presenting with strictures after cardiovascular surgery. Of these patients 5 had penile-brachial pressure indexes less than 0.5 and 6 had weak or absent erections. Of 14 patients studied prospectively by penile blood flow 2 had a low penile-brachial pressure index and suffered urethral strictures 6 weeks after cardiovascular surgery. This finding suggests that urethral ischemia could be a predisposing factor for the development of urethral strictures after cardiovascular surgery.
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Hassouna M, Galeano C, Abdel-Rahman M, Elhilali M. Vesicourethral motility following acute spinal cord transection in the cat. J Urol 1984; 131:370-3. [PMID: 6699976 DOI: 10.1016/s0022-5347(17)50388-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The cause of urinary retention during the phase of spinal shock is still uncertain. In the cat with intact spinal cord, reflex voiding shows a coordination between the longitudinal and circular urethral muscles, the detrusor and the periurethral striated muscles. After transection of the spinal cord in cervical and/or thoracic segments, 26 of 28 cats failed to void. An incoordination between longitudinal, circular, detrusor and periurethral striated muscles was noticed simulating a urethro-urethral and urethrovesical dyssynergia. The 2 cats that voided 6 hours after the cord section showed a return of synergism between longitudinal, circular, detrusor and periurethral striated muscles. The conventional pharmacologic manipulation used during the early period following spinal cord transection, bethanechol chloride and phentolamine, failed to achieve proper bladder emptying because it did not correct the dyssynergic pattern.
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Abdel-Hakim A, Hassouna M, Rioux F, St-Pierre S, Abdel-Rahman M, Galeano C, Elhilali M. Response of urethral smooth muscles to pharmacological agents. II. Noncholinergic, nonadrenergic agonists and antagonists. J Urol 1983; 130:988-91. [PMID: 6195358 DOI: 10.1016/s0022-5347(17)51613-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
We studied the effects of a variety of noncholinergic, nonadrenergic agents on the smooth muscles of the cat urethra. Prostaglandin F2 alpha contracted both urethral muscle layers to a similar extent. Prostaglandin E2 contracted the longitudinal and relaxed the circular muscle layers. The effects of the prostaglandins seem to be directly myogenic since cholinergic and adrenergic blockers and tetrodotoxin did not affect them. Bradykinin and substance P contracted both urethral muscle layers. Other tested agonists (neurotensin, vasoactive intestinal peptide, cyclic 3,5 adenosine monophosphate, adenosine diphosphate sodium, cyclic 3,5 guanosine monophosphate sodium, bombesin) had no effect on the cat urethral smooth muscles.
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Hassouna M, Galeano C, Lamarche J, Abdel-Rahman M, Elhilali MM. Bladder and urethral dynamics in multiple sclerosis-like animal model. J Urol 1983; 130:806-10. [PMID: 6887425 DOI: 10.1016/s0022-5347(17)51470-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Multiple sclerosis-like disease was induced in 18 rabbits by immunization with guinea pig spinal cord. The urodynamic studies conducted in the immunized rabbits showed a significantly lower maximal urethral pressure and a lower bladder capacity than those in the control group. We compared the urodynamic, clinical and histopathological parameters in the immunized rabbits. We conclude that the rabbit is an acceptable model for studying the bladder and urethral dynamics during various phases of experimental allergic encephalomyelitis (multiple sclerosis-like disease).
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Abdel-Hakim A, Bernstein J, Hassouna M, Elhilali MM. Visual internal urethrotomy in management or urethral strictures. Urology 1983; 22:43-5. [PMID: 6868248 DOI: 10.1016/0090-4295(83)90344-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Visual internal urethrotomy was used in the treatment of urethral strictures in 103 patients. The procedure was performed mostly under local anesthesia. Urethral catheter for forty-eight hours or urethral splinting for two weeks was used as complementary treatment in some cases. We obtained an overall success rate of 95.1 per cent.
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Hassouna M, Abdel-Hakim A, Abdel-Rahman M, Galeano C, Elhilali MM. Response of the urethral smooth muscles to pharmacological agents. I. Cholinergic and adrenergic agonists and antagonists. J Urol 1983; 129:1262-4. [PMID: 6133969 DOI: 10.1016/s0022-5347(17)52672-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
We studied the effects of cholinergic and adrenergic agents on the 2 muscle layers of the proximal urethra of the cat. Strips were challenged with bethanechol chloride, phenylephrine and isoproterenol. Bethanechol chloride caused contraction of the longitudinally oriented strips; the circularly oriented strips revealed either minimal or no response to the same doses. The difference between the response of the 2 layers was highly significant (p less than 0.001). Phenylephrine stimulated both layers with a nonsignificant difference. Isoproterenol caused relaxation of both layers with a significant action on the circularly oriented fibers (p less than 0.05). It could be concluded that the cholinergic effect which is predominant on the longitudinal fibers is important for voiding by shortening the proximal urethra. alpha-adrenergic innervation of the bladder neck has a function during ejaculation: closure of the bladder outlet by the circular fibers. beta-adrenergic agonists decrease the urethral pressure probably by relaxing both layers with a dominant effect on the circular layer.
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Hassouna M, Galeano C, Abdel-Rahman M, Elhilali M. Urodynamic studies in the rabbit under the immobility reflex. Neurourol Urodyn 1983. [DOI: 10.1002/nau.1930020311] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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