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J S Paick

Publications and source records attributed to J S Paick.

At least 19 recordsLinked to original sources
PubMed2003

A double-blind, randomised- placebo, controlled, parallel group, multicentre, flexible-dose escalation study to assess the efficacy and safety of sildenafil administered as required to male outpatients with erectile dysfunction in Korea.

The efficacy and safety of sildenafil was evaluated in a randomiSed, double-blind, placebo-controlled, flexible-dose study in Korean men aged 28-78 y with erectile dysfunction (ED) of broad-spectrum aetiology and more than 6 months duration. A total of 133 patients were randomised at six centres in Korea to receive either sildenafil (50 mg initially, increased if necessary to l00 mg or decreased to 25 mg depending on efficacy and tolerance) (n=66) or matching placebo (n=67) taken on an 'as needed' basis l h prior to anticipated sexual activity for a period of 8 weeks. At the end of this time, the primary efficacy variables relating to the achievement and maintenance of erections sufficient for sexual intercourse, and the secondary efficacy variables, which included: (1) the five separate domains of sexual functioning of the International Index of Erectile Function (IIEF) scale, (2) the percentage of successful intercourse attempts, and (3) a global assessment of erections, were all statistically significantly improved by sildenafil in comparison with placebo (P&<0.0001). Treatment-related adverse events occurred in 56.1% of patients receiving sildenafil and 20.9% receiving placebo. The most common adverse events with sildenafil were vasodilatation (flushing), headache and abnormalities in colour vision (31.8, 22.7 and 6.1% of patients, respectively), and most were mild in nature. The efficacy and safety of sildenafil in this population of Korean men appears similar to that reported in other studies in western populations.

Adult↗
PubMed2003

Clinical efficacy and tolerability of extended-release tolterodine and immediate-release oxybutynin in Japanese and Korean patients with an overactive bladder: a randomized, placebo-controlled trial.

OBJECTIVE: To compare extended-release (ER) tolterodine and immediate-release (IR) oxybutynin with placebo in Japanese and Korean patients with an overactive bladder (OAB). PATIENTS AND METHODS: Men and women aged >or= 20 years with symptoms of urinary urgency, urinary frequency (>or= 8 micturitions/24 h), urge incontinence (>or= 5 episodes/week) and symptoms of OAB for >or= 6 months were randomized to double-blind treatment with tolterodine ER 4 mg once daily, oxybutynin IR 3 mg three times daily or placebo for 12 weeks. Efficacy assessments included changes from baseline in numbers of incontinence episodes per week, voids/24 h and mean volume voided/void. Patient perceptions of bladder condition, urgency and treatment benefit were also assessed. RESULTS: In all, 608 patients were randomized to treatment with tolterodine (240), oxybutynin (246) or placebo (122). More patients prematurely withdrew on oxybutynin (23%) than with tolterodine (10.4%) or placebo (16.4%). After 12 weeks of treatment, the median number of incontinence episodes/week was reduced significantly more in the tolterodine (79%; P= 0.0027) and oxybutynin groups (76.5%; P= 0.0168) than on placebo (46.4%). There were also significantly greater improvements in the number of voids/24 h and volume voided/void with tolterodine and oxybutynin than with placebo. More patients in the tolterodine and oxybutynin than in the placebo groups reported improvements in perceived bladder condition, ability to hold urine and treatment benefit. Patients treated with oxybutynin reported more adverse events than those treated with tolterodine or placebo. Dry mouth was significantly more common with oxybutynin than with tolterodine (53.7% vs. 33.5%; P < 0.001), and occurred in 9.8% of placebo patients. CONCLUSION: Tolterodine ER has similar efficacy but is better tolerated than oxybutynin IR in Japanese and Korean patients with OAB.

Adult↗
PubMed2000

Microsurgical single tubular epididymovasostomy: assessment in the era of intracytoplasmic sperm injection.

OBJECTIVE: To reevaluate the role of microsurgical single tubular epididymovasostomy for the treatment of obstructive azoospermia in the era of intracytoplasmic sperm injection (ICSI). DESIGN: Retrospective clinical study. SETTING: University infertility clinic. PATIENT(S): Sixty-one patients with obstructive azoospermia who underwent microsurgical single tubular epididymovasostomy. INTERVENTION(S): Microsurgical single tubular epididymovasostomy. MAIN OUTCOME MEASURE(S): The overall patency and live-birth rates and factors that influenced the surgical outcome. RESULT(S): The overall patency rate after surgery was 68.9% (42/61) and the live-birth rate 31.1% (19/61). Of the 19 live-birth cases, 11 were achieved by natural means and 2 were achieved by conventional IVF soon after the operation, then subsequently by natural conception. The remaining 6 were the result of conventional IVF after surgery. An analysis of the potential prognostic factors previously associated with epididymovasostomy indicated that none had a statistically significant correlation with surgical outcome. In cases of patency, the partners were stratified into a younger group (21-30 years; n = 12) and an older group (31-36 years; n = 30). There was no statistically significant difference between the groups in the live-birth rate regardless of the means of conception (natural versus conventional IVF). CONCLUSION(S): This study demonstrates that the results obtained by microsurgical single tubular epididymovasostomy are comparable to those obtained with the use of IVF and ICSI. Even in this era of ICSI, the option of microsurgical single tubular epididymovasostomy should be considered because ICSI involves surgery to retrieve sperm and complex invasive treatment of the wife.

Adult↗
PubMed2000

Transurethral resection of the ejaculatory duct.

Complete bilateral ejaculatory duct obstruction has long been recognized as an uncommon, treatable form of male infertility. Partial ejaculatory duct obstruction reflects a disturbance of ejaculation where sperm quality is impaired during transit through the distal vas deferens and ejaculatory ducts. With the advent and increased use of high-resolution transrectal ultrasonography, abnormalities of the distal ejaculatory ducts related to infertility have been well documented. Although there are no pathognomonic findings associated with ejaculatory duct obstruction, several clinical findings are highly suggestive. In an infertile man with oligospermia or azoospermia with low ejaculate volume, normal secondary sexual characteristics, testes and hormonal profile and dilated seminal vesicles, midline cyst, or calcification on transrectal ultrasonography, ejaculatory duct obstruction is suggested. Of course, other causes of infertility may be concomitantly present and need to be searched for and treated as well. In selected cases, transurethral resection has resulted in marked improvement in semen parameters and pregnancies have been achieved. As is the case with all surgical procedures, proper patient selection and surgical experience are necessary to obtain optimal results. However, it appears that the treatments currently available for relief of ejaculatory obstruction are not optimally effective. Only approximately one half of treated patients will have an improvement in semen parameters and only about one quarter of treated patients will contribute to a pregnancy. What remains to be determined is how to manage the additional nearly 50% of patients who do not benefit from transurethral resection of ejaculatory obstruction. Based on my experience, I suggest that transrectal ultrasonography should be the first diagnostic procedure used when infertile men are suspected of having ejaculatory duct obstruction; however, vasography should still be considered for a more comprehensive diagnosis of ejaculatory duct obstruction. In patients showing atrophic seminal vesicles on transrectal ultrasonography and having a history of pulmonary tuberculosis, further study is not necessary and microscopic epididymal sperm aspiration is recommended for in vitro fertilization. Qualitative measurement of semen fructose may be helpful in the diagnosis of partial ejaculatory duct obstruction. Patients having midline cyst and being treated by transurethral resection are expected to have the best outcome.

Ejaculatory Ducts↗
PubMed1999

Microdeletions within the azoospermia factor subregions of the Y chromosome in patients with idiopathic azoospermia.

OBJECTIVE: To examine the patterns of submicroscopic DNA deletions in the AZF (AZoospermia Factor) subregions of the Y chromosome in patients with idiopathic azoospermia. DESIGN: Controlled clinical study. SETTING: University-based infertility clinic. PATIENT(S): Infertile men (n = 40) with nonobstructive, idiopathic azoospermia. The control group consisted of proven fathers (n = 14) and healthy women (n = 4). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Semen analysis; polymerase chain reaction amplification of the 37 loci spanning the AZFa, AZFb, and AZFc subregions of the Y chromosome; serum FSH, LH, and testosterone levels; and testicular histologic analysis. RESULT(S): Testicular histologic analysis of the subjects revealed Sertoli cell-only syndrome (n = 36) and spermatogenic arrest (n = 4). Microdeletions of the Y chromosome were found in eight (20%) of the patients with azoospermia. All eight affected patients had interstitial microdeletions within the AZFc subregion. Patients with Sertoli cell-only syndrome had additional microdeletions in regions distal to DAZ (Deleted in Azoospermia), although DAZ deletion was observed in seven of the eight affected patients. In five patients, microdeletions were found in the AZFb region containing RBM (RNA Binding Motif). CONCLUSION(S): Our results add to the evidence supporting the current suggestion that there is a cause-and-effect relation between Yq11 microdeletions in the AZF region and azoospermia.

Adult↗
PubMed1999

Short-term analysis of the effects of as needed use of sertraline at 5 PM for the treatment of premature ejaculation.

OBJECTIVES: Pharmacotherapy using selective serotonin reuptake inhibitors (SSRIs) for men with primary premature ejaculation is promising. In particular, the strategy of taking a pill "as needed" may offer an attractive option. To investigate the possibility of self-therapy for the treatment of premature ejaculation, we compared the efficacy of sertraline taken as needed with that of continuous medication. METHODS: Since 1996, we have treated 24 men with sertraline on an as needed basis for primary premature ejaculation. Sertraline was chosen from among the SSRIs because a large dose need not be divided and because peak plasma levels occur 4 to 8 hours after oral administration, making 5 PM a suitable time for administration (by which time a man may know whether sexual intercourse is likely to occur later that evening). Each patient was started on 50 mg daily for 2 weeks, and the dose was then adjusted to 50 or 100 mg on the day of intercourse only (PRN). RESULTS: After 6 weeks, 18 men were still taking medication, and 6 had dropped out. Among the 18, the mean ejaculation latency was 23 +/- 19 seconds before treatment, 5.9 +/- 4.2 minutes after 2 weeks of 50 mg daily, 5.1 +/- 3.8 minutes after 2 weeks of 50 or 100 mg PRN, and 4.5 +/- 2.7 minutes after 4 weeks of 50 or 100 mg PRN. Mean sexual satisfaction scores (5, extremely satisfied; 0, extremely unsatisfied) for men were 0.8 +/- 0.8 before treatment, 3.8 +/- 1.2 after 2 weeks of 50 mg daily, 3.4 +/- 1.0 after 2 weeks of 50 or 100 mg PRN, and 3.2 +/- 0.7 after 4 weeks of 50 or 100 mg PRN. For their partners, mean sexual satisfaction scores were 1.1 +/- 0.7 before treatment, 3.2 +/- 1.6 after 2 weeks of 50 mg daily, 3.1 +/- 1.4 after 2 weeks of 50 or 100 mg PRN, and 3.3 +/- 1.2 after 4 weeks of 50 or 100 mg PRN. Side effects were intermittent excessive delay of ejaculation in 1 patient, fatigue in 2, and numbness in 1. CONCLUSIONS: If our results are supported by additional long-term clinical studies, self-therapy with sertraline taken PRN at 5 PM for the treatment of premature ejaculation could be as attractive as self-injection therapy for the treatment of erectile dysfunction.

Adult↗
PubMed1999

Effects of androgens on the expression of nitric oxide synthase mRNAs in rat corpus cavernosum.

OBJECTIVE: To examine the effects of androgens on erectile response and the expression of nitric oxide synthase (NOS) isoform mRNAs in the penile corpus cavernosum of castrated rats. MATERIALS AND METHODS: The study comprised 50 adult male Sprague-Dawley rats in five groups: sham controls; castrated; castrated and receiving testosterone; castrated and receiving dihydrotestosterone (DHT); castrated and receiving testosterone and 5alpha-reductase inhibitor (finasteride). Androgen replacements were administered via implants of silicone tubing. After 7 days, some animals underwent electrical stimulation of the cavernosal nerves and the remainder were used for further analysis. NOS activity was measured in the soluble fraction of the corpus cavernosum, using the Griess reaction. Total RNA was isolated and nNOS and eNOS mRNA expression examined using semiquantitative reverse-transcriptase polymerase chain reaction. RESULTS: Castration caused a marked decrease in erectile response and the ratio of maximal intracavernosal pressure (ICPmax) to systemic blood pressure (SBP), although both testosterone and DHT effectively restored the response to normal. NOS activity and the amount of nNOS mRNA were reduced in castrated rats but restored by androgen replacement. Although there was no significant difference in NOS activity between the androgens, nNOS mRNA expression was higher in rats treated with DHT. There were no effects of androgen in rats treated with finasteride, as the ICPmax/SBP ratio, NOS activity and amount of nNOS mRNA decreased. eNOS mRNA expression was independent of androgen. CONCLUSIONS: Androgens enhance nNOS gene expression in the penile corpus cavernosum of rats, suggesting that they play an important role in maintaining NOS activity. Of the two androgens, DHT was more potent.

Androgens↗
PubMed1999

The effects of androgen on penile reflex, erectile response to electrical stimulation and penile NOS activity in the rat.

AIM: To investigate the effects of androgen on penile erection through the reflex arc and penile corpus cavernosum, and study the respective roles of testosterone (T) and dihydrotestosterone (DHT) in penile erection in rats. METHODS: Male Sprague-Dawley rats were castrated and implanted with silastic brand silicone tube containing T or DHT, with or without daily injections of a 5alpha-reductase inhibitor, MK-434. The penile reflex, erectile response to electrical stimulation (ES) of the cavernous nerves and penile nitric-oxide synthase (NOS) activity were observed under varying androgenic status. RESULTS: Penile reflex erection in the rat was, on the whole, related to serum T levels though the number of glans engorgements was not. The number of cups and flips was significantly decreased by castration, and restored to the control level by T supplementation. Erectile response to ES and NOS activity in penile tissue was also related to serum T level. T administered together with a 5alpha-reductase inhibitor no longer restored the number of reflex erection, erectile responses to ES and NOS activity in the corpus caveenosum. CONCLUSION: Androgen influenced the penile reflex arc, corpus cavernosum, and the perineal striated muscles. In reflex erection, erectile response to ES and penile NOS activity in the rat, T seems to be first converted to DHT, the more active androgen modality.

Animals↗
PubMed1998

Penile sensitivity in men with premature ejaculation.

Premature ejaculation is the most prevalent form of male sexual dysfunction, but its cause has not been well established. Recent studies have indicated that in men with premature ejaculation, penile sensitivity is increased. To investigate whether penile hypersensitivity is a cause of premature ejaculation, we prospectively evaluated the penile sensitivity of 18 patients with a lifelong history of premature ejaculation from the first coital experience and 15 controls, both in the flaccid and erect state. We used an SMV-5 vibrometer (Suzuki-Matsuoka, Teknologue, Tokyo, Japan), which automatically controls stimulatory strength; its precision and reproducibility are thus higher than analogue-type biothesiometers. At the styloid process of the ulna and medial maleolus of the tibia, there was no significant statistical difference in vibratory threshold between the two groups (P > 0.05). Also we did not find significant statistical differences in sensitivity of the glans penis, dorsum of the penile shaft, or frenulum of the penis between the two groups, in either the flaccid or erect state (P > 0.05). According to our results, penile hypersensitivity, as measured by an SMV-5 vibrometer, does not appear to be a major factor contributing to premature ejaculation.

Adult↗
PubMed1998

Ejaculatory duct obstruction: TRUS-guided opacification of seminal tracts.

OBJECTIVE: To assess the usefulness of TRUS-guided aspiration and opacification of seminal tracts in the evaluation and management of patients with ejaculatory duct obstruction (EDO). METHODS: In 21 men who had dilated seminal vesicles and/or midline cysts on TRUS, a mixture of contrast media and indigocarmine was injected and then pelvic radiographs were taken. RESULTS: The diagnoses based on the findings of TRUS-guided opacification were bilateral EDO in 9 patients, unilateral EDO in 1, and midline cyst with EDO in 11. Midline cysts had communication with seminal tracts in 7. Transurethral unroofing was performed in 12, in all of whom blue color of the injected indigocarmine facilitated the surgical procedure. CONCLUSION: TRUS-guided opacification of the seminal tracts with a mixture of contrast media and indigocarmine may be valuable in the evaluation and management of the patients with EDO.

Adult↗
PubMed1998

Morphological classification of sperm heads using artificial neural networks.

In male reproducible health and fertility and IVF (in-vitro fertilization), morphological analysis of sperm has been most important. But the traditional tools for semen analysis are subjective, imprecise, inaccurate, difficult to standardize, and reproduce mainly due to their manually oriented operations. The purpose of morphological analysis of sperm is to microscopically type-classify sperm according to their morphological characteristics of heads. Until now, the strict criteria method has long been used in clinic to discriminate normal sperm from abnormal. This method cannot classify the diverse groups of abnormal sperm in detail and shows large variations in inter-operators and intra-operator. In this paper, we have studied a new method of sperm morphological classification using artificial neural networks that are widely used in pattern recognition and image processing. With a multi-layer perceptron trained by the error back-propagation algorithm, profile features from digitized sperm images were classified into four classes that consisted of one normal group and three abnormal groups according to their morphological characteristics.

Humans↗
PubMed1996

An experimental study of the effect of ginkgo biloba extract on the human and rabbit corpus cavernosum tissue.

PURPOSE: To investigate the effect of subfractions of extract from the ginkgo on human and rabbit corpus cavernosal tissue and their possible use for the treatment of impotence. MATERIALS AND METHODS: Among the fractions of ginkgo biloba extract (GBE), nonginkgolide nonflavonoid fraction (NGF) has the most potent relaxing effect on vascular smooth muscle. We subfractionated NGF and speculated that some of the subfractions might have a very potent relaxing effect on corpus cavernosal tissue. Thereafter we have studied their effect on human and rabbit corpus cavernosum using organ bath and electrical field stimulation experiments. RESULTS: In the tissue precontracted by norepinephrine (10(-5)M.), corpus cavernosal tissue of human and rabbit showed relaxation in response to subfractions of NGF in a dose-dependent manner. 304U-1 showed the most potent relaxing effect (ED50 = 0.74 mg./ml. in human, ED50 = 0.66 mg./ml. in rabbit). 304U-1 elicits pharmacological actions on corpus cavernosum smooth muscle via the signal transduction pathway whereby relaxation induced by 304U-1 is mediated by intracellular cAMP and perhaps partially by antagonizing of the adrenergic nervous system. A hyperpolarizing effect via potassium channel opening might also be related to this relaxing effect. CONCLUSION: The subfractions of NGF, especially 304U-1, have a relaxing effect on corpus cavernosum tissue. 304U-1, which showed the most potent relaxing effect, can possibly be used as a drug for intracavernosal injection therapy. Considering the fact that the value of ED50 is too high, further fractionation and in vivo study are needed before clinical use in an oral form.

Animals↗
PubMed1994

The neural mechanism of apomorphine-induced erection: an experimental study by comparison with electrostimulation-induced erection in the rat model.

The rat model of an apomorphine (APO)-induced erection is accepted as a rapid, reproducible way of observing whether erectile capability is present. However there are still questions that can be asked about whether an APO erection shares the same neural pathway as a physiologic erection. We compared APO-induced erections of sham-operated rats with those in rats that had the hypogastric, pelvic and cavernous nerves ablated bilaterally. The results suggest that an APO-induced erection is a vascular event primarily mediated via the sacral parasympathetic nerve system and that, in case of injury to the parasympathetic nerve system, it may also be mediated by the thoracolumbar sympathetic pathway. Similarity in the neural pathways between APO-induced erection and a psychogenic erection makes this animal model useful for study of psychogenic erectile reflexes.

Animals↗
PubMed1994

Doppler sonography of deep cavernosal artery of the penis: variation of peak systolic velocity according to sampling location.

To determine if there are significant variations in the peak systolic velocity of cavernosal arteries according to the Doppler sampling location, Doppler sonography was performed in 32 patients with erectile dysfunction and 15 control patients. Doppler spectral waveforms were obtained at proximal and distal locations in cavernosal artery. The peak systolic velocity of the cavernosal artery was 39.0 +/- 11.2 cm/sec in proximal portion and 20.0 +/- 5.6 cm/sec in distal portion in patients with erectile dysfunction. In control patients, the peak systolic velocity was 39.8 +/- 8.0 cm/sec in proximal portion and 21.3 +/- 5.5 cm/sec in distal portion. The peak systolic velocity of the cavernosal artery varies significantly according to the sampling location in patients with erectile dysfunction as well as in control patients. Our study demonstrated that the sampling location needs to be standardized in performing Doppler sonography of the cavernosal arteries, and we propose the proximal cavernosal artery where it angles posteriorly as the standardized sampling location.

Adult↗
PubMed1993

Anatomy of cavernous nerves distal to prostate: microdissection study in adult male cadavers.

Retrograde and antegrade dissections from the penile hilum to the prostatic area and the glans penis were performed in 4 formalin-preserved adult male cadavers. In addition to the medial branches accompanying the urethra, the lateral branches of the cavernous nerves pierced the urogenital diaphragm 4 to 7 mm from the striated muscles of the external sphincter. At the penile region, multiple communications between the cavernous and dorsal nerves were noted that suggest that either the cavernous nerves use the dorsal nerve as a carrier to the distal portion of the penis or the dorsal nerve may itself contain autonomic fibers. These findings will improve our ability to preserve erectile function during pelvic, urethral, and penile surgery.

Adult↗
PubMed1993

Implantable penile venous compression device: initial experience in the chronic canine model.

A prosthetic penile venous compression device was surgically placed in 14 dogs to assess the effects of chronic device implantation and repeated device cycling on cavernous tissue. Duration of device implantation ranged from 37 to 224 days; total number of device cycles ranged from 8 to 59. At recovery, erection was induced by electrostimulation of the pelvic nerve. The device successfully prolonged intracavernous elevation for as much as 30 minutes after inflation. Histologic examination of representative tissue sections through the corpora revealed no evidence of neural injury, vascular compromise, or tissue atrophy. The implantable venous compression device may offer an improved method of treatment of venogenic impotence.

Animals↗