Congenital chylothorax, a condition in which chyle accumulates in the pleural cavity, is extremely rare. The reported incidence is 1 in 24,000 births. Medical treatment using octreotide as well as chemical and surgica...Congenital chylothorax, a condition in which chyle accumulates in the pleural cavity, is extremely rare. The reported incidence is 1 in 24,000 births. Medical treatment using octreotide as well as chemical and surgical pleurodesis has been reported, but also few reports on the successful use of Sildenafil exists. We herein report a case of congenital chylothorax referred to our Hospital at 7 days-old. Sildenafil was introduced on day 6 post intubation. Before the introduction of sildenafil, the peak total daily drainage was 106 ml/kg/day (340 mls/day), and after sildenafil was introduced, the total daily drainage dropped progressively to 10 ml/kg/day by day 11 post intubation. This case report highlights the successful use of oral Sildenafil for treatment of congenital chylothorax and also peculiarities of management related to a resource- constrained developing country setting in Africa.展开更多
Aim： To test the hypothesis that sildenafil （50 mg nightly for one year） can improve spontaneous erectile function （EF） in men with mild-to-moderate arteriogenic erectile dysfunction （ED） responsive to erectoge...Aim： To test the hypothesis that sildenafil （50 mg nightly for one year） can improve spontaneous erectile function （EF） in men with mild-to-moderate arteriogenic erectile dysfunction （ED） responsive to erectogenic treatment. Methods： In a prospective open-label trial, 112 men with ED were randomized to sildenafil 50 mg nightly or sildenafil 50 or 100 mg as needed for 12 months, followed by one-month and 6-month non-medicated periods. Non-randomized, non-medicated men with ED were also assessed. The EF domain of the International Index of Erectile Function （IIEF EF） and the peak systolic velocity （PSV） of penile cavernous arteries were used to measure the efficacy. Results： After sildenafil treatment and a subsequent non-medicated month, IIEF EF was normal in 29 of 48 （60.4%, 95% confidence interval [CI]： 45.3-74.2%） of the nightly group vs. 4 of 49 （8.2%, 95% CI： 2.3-19.6%） of the as-needed group. PSV improved by 11.2 cm/s （95% CI： 4.7-21.4; P = 0.012） in the nightly group but only by 3.4 cm/s （-5.1- 14.7; P = 0.435） in the as-needed group. IIEF EF normalized in 1 of 18 （5.6%, 95% CI： 0.1-27.3%） non-medicated men and the PSV declined slightly. Six months after treatment, the IIEF EF remained normal and PSV was stabilized in most （28/29, 97%） nightly group men who had initially normalized. Conclusion： Sildenafil nightly for one year resulted in ED regression that persisted well beyond the end of treatment, so that spontaneous EF was characterized as normal on the IIEF in most men. The results from this open-label, randomized trial warrant verification under double-blind, placebo-controlled conditions.展开更多
Aim： To assess heine oxygenase-1 （HO-1） activity in the cavemous tissue of sildenafil citrate-treated rats. Methods： One hundred and ninety-two Sprague-Dawley male rats, divided into four equal groups, were invest...Aim： To assess heine oxygenase-1 （HO-1） activity in the cavemous tissue of sildenafil citrate-treated rats. Methods： One hundred and ninety-two Sprague-Dawley male rats, divided into four equal groups, were investigated. Group 1, the control group, received regular animal chow; group 2 received sildenafil citrate by intragastric tube; group 3 received sildenafil and HO inhibitor （zinc protoporphyrin, ZnPP）; and group 4 received sildenafil and nitric oxide synthase （NOS） inhibitor L-nitroarginine methyl ester （L-NAME）. Twelve rats from each group were killed after 0.5 h, 1 h, 2 h and 3 h of drug administration. Then HO-1 activity, cGMP levels and NOS enzymatic activity in the cavernous tissues were estimated. Results： In cavemous tissue, HO-1 activity, NOS enzymatic activity and cGMP concentration increased significantly in sildenafil-treated rats compared to other groups throughout the experiment. Rats receiving either HO or NOS inhibitors showed a significant decrease in these parameters. HO- 1 cavemous tissue activity and NOS enzymatic activity demonstrated a positive significant correlation with cGMP levels （r = 0.646, r = 0.612 respectively; P 〈 0.001）. Conclusion： The actions of PDE5 inhibitor sildenafil citrate in the cavernous tissue are partly mediated through the interdependent relationship between both HO-1 and NOS activities.展开更多
Aim： To determine if there are different penile hemodynamic patterns between sildenafil non-responders and responders by using color Doppler ultrasonography. Methods： A total of 69 erectile dysfunction （ED） patien...Aim： To determine if there are different penile hemodynamic patterns between sildenafil non-responders and responders by using color Doppler ultrasonography. Methods： A total of 69 erectile dysfunction （ED） patients aged 22-79 years were enrolled into the present study. Thirty-eight （55.1%） men with ED who did not respond to four attempts of treatment with 100 mg sildenafil after re-education were classified as sildenafil non-responders. A com- bination of three vasodilator drugs, 1.25 mg papaverine, 0.4 mg phentolamine and 5 ug prostaglandin E1, was given by intracavernous injection before penile Doppler ultrasonography was carried out. The erectile response to intracavernous injection and vascular parameters including peak systolic velocity （PSV）, resistance index （RI）, end diastolic velocity （EDV） and cavernosa artery diameter （CD） were measured and the results between sildenafil nonresponders and responders were compared. Results： No statistical difference in vascular parameters measured by Doppler ultrasonography studies between non-responders and responders was noted. Sildenafil non-responders had a poorer penile rigidity response to intracavernous injection than responders （P 〈 0.05）. Among patients with adequate PSV （〉 30 cm/s） and abnormal EDV （〉 5 cm/s）, individuals in the non-responder group had fewer positive responses to intracavernous vasodilator injection than in the responder group （35.3% vs. 72.2%, P 〈 0.05）. Advanced age and comorbidity with diabetes mellitus were significantly associated with sildenafil non-response （P 〈 0.05）. Conclusion： Sildenafil non-responders were characterized by a poorer penile rigidity response to intracavernous injection and had an associated impaired veno-occlusive mechanism. Advanced age and comorbidity with diabetes mellitus were two common factors associated with non-response.展开更多
To evaluate patient preferences for sildenafil citrate or tadalafil （PDE-5 inhibitors available for the treatment of erectile dysfunction [ED]） and assess potential reasons for these preferences. Methods： This open...To evaluate patient preferences for sildenafil citrate or tadalafil （PDE-5 inhibitors available for the treatment of erectile dysfunction [ED]） and assess potential reasons for these preferences. Methods： This open-label study was conducted on Korean men taking sildenafil, at least 6 weeks prior to study entry, for ED. Following screening, patients continued sildenafil treatment for 4 weeks, then after a 1-week washout period, switched to tadalafil for 8 weeks. Patients then continued with their treatment of choice during an extension phase. Psychosocial factors （time concern, spontaneity, sexual self-confidence） were evaluated using Psychological and Interpersonal Relation- ship Scales （PAIRS）, while timing of dose to sexual attempt patterns were assessed from patient diaries. Results： The present study enrolled 160 Korean men （mean age 55 years） with prior median sildenafil use of 585 days. During the extension phase, 73.7% of patients elected to take tadalafil, whereas 26.3% chose sildenafil （P 〈 0.001）. After switching from sildenafil to tadalafil, mean PAIRS time concern scores decreased from 2.54 to 2.42 （P = 0.002）, with no statistically significant differences observed between the sildenafil and tadalafil assessment phases in sexual spontaneity and self-confidence scores. Sexual attempts made 〉 4 h to 〈 36 h post-dose occurred in 4.5% of patients during the sildenafil assessment phase compared with 17.5% during the tadalafil assessment phase. Conclusion： After experiencing both sildenafil and tadalafil, the majority of patients exhibited a preference for tadalafil. This preference might be influenced by psychosocial factors, such as decreased time concerns, and a broader window of opportunity available for sexual activity.展开更多
Aim： To assess the efficacy of sildenafil and continuous positive airway pressure （CPAP） in the treatment of concurrent erectile dysfunction （ED） with obstructive sleep apnea （OSA）, and to gauge the level of tr...Aim： To assess the efficacy of sildenafil and continuous positive airway pressure （CPAP） in the treatment of concurrent erectile dysfunction （ED） with obstructive sleep apnea （OSA）, and to gauge the level of treatment satisfaction in patients and their partners. Methods： Forty men were treated for 12 weeks with sildenafil 100 mg （20 men） or CPAP during nighttime sleep （20 men）. Treatment efficacy was assessed by the rate of successful intercourse attempts, and satisfaction with treatment was assessed by patients＇ and partners＇ answers to question 1 of the Erectile Dysfunction Inventory of Treatment Satisfaction. Results： Under sildenafil, 128 of 249 （51.4%） intercourse attempts were successful; under CPAP, 51 of 193 （26.9%） attempts were successful （^cp 〈 0.001）. Erectile function was improved in both groups. After sildenafil and CPAP treatment, the mean International Index for Erectile Function domain scores were 14.3 and 10.8, respectively （^bp = 0.025）, compared to 7.8 and 7 at baseline, respectively. CPAP and sildenafil were well tolerated. Sporadic episodes of nasal dryness under CPAP and transient headache and flushing under sildenafil were not significant. Fifty percent of patients treated with sildenafil and 25% with CPAP were satisfied with the treatment, and their partners were equally satisfied. The satisfaction scores for both patients and partners under sildenafil were superior to those under CPAP （^cP 〈 0.002）. Conclusion： Both sildenafil 100 mg and CPAP, used separately, had positive therapeutic impact but sildenafil was superior. Patients and their partners were more satisfied with sildenafil for the treatment of ED. However, because of the high proportion of dissatisfied men and partners, new therapeutic agents or a combination of the two methods must be studied further.展开更多
In vitro interaction of sildenafil citrate (SC) with bovine serum albumin (BSA) was investigated at two excitation wavelengths of BSA (280 nm and 293 nm) at two different temperatures (298 K and 308 K) by fluorescence...In vitro interaction of sildenafil citrate (SC) with bovine serum albumin (BSA) was investigated at two excitation wavelengths of BSA (280 nm and 293 nm) at two different temperatures (298 K and 308 K) by fluorescence emission spectroscopy. The study showed that quenching of BSA fluores-cence by sildenafil citrate was the result of formation BSA-SC complex with probable involvement of both tryptophan and tyrosine residues of BSA. Fluorescence quenching constant was determined from Stern-Volmer equation, and both static quenching and dynamic quenching were showed for BSA by SC at the conditions. Van’t Hoff equation was used to measure the thermodynamic parameters ΔG, ΔH, and ΔS at the temperatures which indicated that the hydrogen bond and the hydrophobic forces played major roles for BSA-SC complexation. The binding number (n) was found to be ≈1 indicating that one mole BSA bound with one mole SC. The binding affinity of SC to BSA was calculated at different temperatures. The binding constant was decreased with increasing temperatures indicating that stability of BSA-SC complex decreased with increasing temperatures.展开更多
Aim： To determine the effect of sildenafil citrate on the nocturnal penile erections （i.e. time to onset, the duration of erection, and the interval between first and second erections） of healthy young men. Methods...Aim： To determine the effect of sildenafil citrate on the nocturnal penile erections （i.e. time to onset, the duration of erection, and the interval between first and second erections） of healthy young men. Methods： Twenty-two potent men, 23-29 years old, were recruited for the study. All subjects completed three sessions over consecutive nights using the RigiScan monitoring device （Dacomed, Minneapolis, USA）. After a first night of adaptation, night 2 records were their baseline values, and on night 3 they received 100 mg of sildenafil citrate. Statistical comparisons were done between the second and third night data. Results： The mean time to onset of the first erection with sildenafil citrate was （34 ± 18） min, whereas it was （74 ± 24） min （P 〈 0.001） without sildenafil citrate. The number of erections observed during the first 5 h after sildenafil citrate medication was 3.6 ± 0.5 in contrast to 2.4 ± 0.5 with no medica- tion （P = 0.001）. The interval between first and second erections was shorter with sildenafil citrate： （52 ± 26） min vs. （85 ± 34） min （P = 0.01）. The duration of the last erection was statistically significantly longer with the sildenafil citrate： （64 ± 33） min vs. （42 ± 28） min （P 〈 0.01）. Conclusion： Healthy young men achieved erection within 34 min after sildenafil citrate administration, which is shorter than the 1 h interval proposed by the manufacturer. The interval between the first and second erections was shorter and the duration of the last nocturnal erection was longer.展开更多
AIM： To investigate if sildenafil increases splanchnic blood flow and changes the hepatic venous pressure gradient （HVPG） in patients with cirrhosis. Phosphodiesterase type-5 inhibitors are valuable in the treatmen...AIM： To investigate if sildenafil increases splanchnic blood flow and changes the hepatic venous pressure gradient （HVPG） in patients with cirrhosis. Phosphodiesterase type-5 inhibitors are valuable in the treatment of erectile dysfunction and pulmonary hypertension in patients with end-stage liver disease. However, the effect of phosphodiesterase type-5 inhibitors on splanchnic blood flow and portal hypertension remains essentially unknown. METHODS： Ten patients with biopsy proven cirrhosis （five females/five males, mean age 54：1：8 years） and an HVPG above 12 mmHg were studied after informed consent. Measurement of splanchnic blood flow and the HVPG during liver vein catheterization were done before and 80 min after oral administration of 50 mg sildenafil. Blood flow was estimated by use of indocyanine green clearance technique and Fick＇s principle, with correction for non-steady state. RESULTS： The plasma concentration of sildenafil was 222 ± 136 ng/mL 80 min after administration. Mean arterial blood pressure decreased from 77 ±7 mmHg to 66 ± 12 mmHg, P = 0.003, while the splanchnicblood flow and oxygen consumption remained unchanged at 1.14 ± 0.71 L/min and 2.3 ± 0.6 mmol/ min, respectively. Also the HVPG remained unchanged （18 ± 2 mmHg vs 16 ± 2 mmHg） with individual changes ranging from -8 mmHg to ±2 mmHg. In seven patients, HVPG decreased and in three it increased. CONCLUSION： In spite of arterial blood pressure decreases 80 min after administration of the phosphodiesterase type-5 inhibitor sildenafil, the present study could not demonstrate any clinical relevant influence on splanichnic blood flow, oxygen consumption or the HVPG.展开更多
Aim: To examine the effect of sildenafil citrate on penile erection of male rhesus macaque. Methods: Twenty Macaca mulatta were divided into the sildenafil treated and the control groups of 10 animals each. The penile...Aim: To examine the effect of sildenafil citrate on penile erection of male rhesus macaque. Methods: Twenty Macaca mulatta were divided into the sildenafil treated and the control groups of 10 animals each. The penile size, the corpus cavernosal electromyogram (EMG) and the intra-corpus cavernosal pressure (ICP) were determined. Results: The diameter of penis and the ICP were significantly increased and the corpus cavernosal EMG significantly reduced in the sildenafil group. Conclusion: Sildenafil citrate increases the penile size and ICP and reduces the corpus cavernosal EMG in male rhesus macaque.展开更多
Aim: To investigate the reasons for discontinuations of sildenafil after the successful restoration of erectile function. Methods: One hundred fifty six patients, whose scores of erectile function domain of the 15-ite...Aim: To investigate the reasons for discontinuations of sildenafil after the successful restoration of erectile function. Methods: One hundred fifty six patients, whose scores of erectile function domain of the 15-item International Index of Erectile Function (IIEF) increased to 26 or more after sildenafil medication, were included in this study. Six-months after the first sildenafil prescription, compliance to medication and the reason for discontinuity were reviewed by chart or surveyed by telephone. Results: Fifty-four (34.6%) of the 156 successfully treated patients discontinued sildenafil medication. The r easons for discontinuance were shortcomings in the partners' or patients' emotional readiness for the restoration of sexual life after long-term abstinence (37.0%), fear of possible side effects (18.5 %), recovery of spontaneous erection (14.8 %), postponement of ED treatment because of co morbid disease treatment (11.1%), unwillingness to accept drug-dependent erection (7.4%), high drug cost (3.7%), unacceptability of planned sexual activity (3.7%) and lack of sexual interesi (3.7%). Conclusion: The reasons for discontinuing sildenafil medication were primarily emotional or relationship-oriented, which indicates that simple recovery of a rigid erection is insufficient to restore sexual activity. More education about the effects of drug and the counseling of both partners is recommended to promote the successful recovery of sexual activity.展开更多
<abstract>Aim: To determine the ultrastructural effects of sildenafil on the female genital organs. Methods: Twenty female cycling Wistar albino rats weighing 250±20 g were randomly divided into two groups ...<abstract>Aim: To determine the ultrastructural effects of sildenafil on the female genital organs. Methods: Twenty female cycling Wistar albino rats weighing 250±20 g were randomly divided into two groups of 10 each. Rats of one group were gavaged with 0.5 mg·kg-1·d-1 of sildenafil 3 days in a week for 4 weeks and the other served as the controls. After cessation of treatment animals were sacrificed by cervical dislocation under methoxyflurane anaesthesia. The clitoris, vagina, uterus and bartholin glands were taken at the estrous and were fixed with 10 % formalin solution for light microscopy and 2.5 % glutaraldehyde and osmic acid for electron microscopy. Results: Under the light microscope, the fibrocollageous tissue was found increased, the capillaries enlarged and the connecting tissue elements increased in the corpus cavernosum in the treated group. On electron microscopy, increased connective tissue, fibroblasts with notched nucleus, shorten immature collagen fibers without striation were seen. Abundant foldings and penetration with collagen bundles were observed in the basal membrane. Large connection complexes, especially gap junctions among the wide capillary endothelial cells were observed. Conclusion: There are evident histological changes due to sildenafil citrate in female rat corpus cavernosum. The clitoris and bartholin glands were the most effected organs. While the histopathological changes of clitoral tissue could be expected, an increase in the mass of bartholin gland was surprised.展开更多
Sildenafil citrate is a potent and selective phosphodiesterase-5inhibitor. It is effectively used in the treatment of erectile dysfunction and pulmonary arterial hypertension. The drug is rapidly absorbed and pharmaco...Sildenafil citrate is a potent and selective phosphodiesterase-5inhibitor. It is effectively used in the treatment of erectile dysfunction and pulmonary arterial hypertension. The drug is rapidly absorbed and pharmacologically acts within30 min to 1 h after oral administration. However, it has a relatively low absolute bioavailability of 41%because its limited solubility in water is the major problem (1)To improve the oral bioavailability of poorly water-soluble drugs.展开更多
Dear Editor,Sildenafil citrate（Viagra;Pfizer Pharmaceuticals,New York,NY,USA）,a selective inhibitor of phosphodiesterase type 5（PDE-5）,is widely used for erectile dysfunction.Its clinical recommended dosage is 25 ...Dear Editor,Sildenafil citrate（Viagra;Pfizer Pharmaceuticals,New York,NY,USA）,a selective inhibitor of phosphodiesterase type 5（PDE-5）,is widely used for erectile dysfunction.Its clinical recommended dosage is 25 to 100 mg per day.展开更多
文摘Congenital chylothorax, a condition in which chyle accumulates in the pleural cavity, is extremely rare. The reported incidence is 1 in 24,000 births. Medical treatment using octreotide as well as chemical and surgical pleurodesis has been reported, but also few reports on the successful use of Sildenafil exists. We herein report a case of congenital chylothorax referred to our Hospital at 7 days-old. Sildenafil was introduced on day 6 post intubation. Before the introduction of sildenafil, the peak total daily drainage was 106 ml/kg/day (340 mls/day), and after sildenafil was introduced, the total daily drainage dropped progressively to 10 ml/kg/day by day 11 post intubation. This case report highlights the successful use of oral Sildenafil for treatment of congenital chylothorax and also peculiarities of management related to a resource- constrained developing country setting in Africa.
文摘Aim： To test the hypothesis that sildenafil （50 mg nightly for one year） can improve spontaneous erectile function （EF） in men with mild-to-moderate arteriogenic erectile dysfunction （ED） responsive to erectogenic treatment. Methods： In a prospective open-label trial, 112 men with ED were randomized to sildenafil 50 mg nightly or sildenafil 50 or 100 mg as needed for 12 months, followed by one-month and 6-month non-medicated periods. Non-randomized, non-medicated men with ED were also assessed. The EF domain of the International Index of Erectile Function （IIEF EF） and the peak systolic velocity （PSV） of penile cavernous arteries were used to measure the efficacy. Results： After sildenafil treatment and a subsequent non-medicated month, IIEF EF was normal in 29 of 48 （60.4%, 95% confidence interval [CI]： 45.3-74.2%） of the nightly group vs. 4 of 49 （8.2%, 95% CI： 2.3-19.6%） of the as-needed group. PSV improved by 11.2 cm/s （95% CI： 4.7-21.4; P = 0.012） in the nightly group but only by 3.4 cm/s （-5.1- 14.7; P = 0.435） in the as-needed group. IIEF EF normalized in 1 of 18 （5.6%, 95% CI： 0.1-27.3%） non-medicated men and the PSV declined slightly. Six months after treatment, the IIEF EF remained normal and PSV was stabilized in most （28/29, 97%） nightly group men who had initially normalized. Conclusion： Sildenafil nightly for one year resulted in ED regression that persisted well beyond the end of treatment, so that spontaneous EF was characterized as normal on the IIEF in most men. The results from this open-label, randomized trial warrant verification under double-blind, placebo-controlled conditions.
文摘Aim： To assess heine oxygenase-1 （HO-1） activity in the cavemous tissue of sildenafil citrate-treated rats. Methods： One hundred and ninety-two Sprague-Dawley male rats, divided into four equal groups, were investigated. Group 1, the control group, received regular animal chow; group 2 received sildenafil citrate by intragastric tube; group 3 received sildenafil and HO inhibitor （zinc protoporphyrin, ZnPP）; and group 4 received sildenafil and nitric oxide synthase （NOS） inhibitor L-nitroarginine methyl ester （L-NAME）. Twelve rats from each group were killed after 0.5 h, 1 h, 2 h and 3 h of drug administration. Then HO-1 activity, cGMP levels and NOS enzymatic activity in the cavernous tissues were estimated. Results： In cavemous tissue, HO-1 activity, NOS enzymatic activity and cGMP concentration increased significantly in sildenafil-treated rats compared to other groups throughout the experiment. Rats receiving either HO or NOS inhibitors showed a significant decrease in these parameters. HO- 1 cavemous tissue activity and NOS enzymatic activity demonstrated a positive significant correlation with cGMP levels （r = 0.646, r = 0.612 respectively; P 〈 0.001）. Conclusion： The actions of PDE5 inhibitor sildenafil citrate in the cavernous tissue are partly mediated through the interdependent relationship between both HO-1 and NOS activities.
文摘Aim： To determine if there are different penile hemodynamic patterns between sildenafil non-responders and responders by using color Doppler ultrasonography. Methods： A total of 69 erectile dysfunction （ED） patients aged 22-79 years were enrolled into the present study. Thirty-eight （55.1%） men with ED who did not respond to four attempts of treatment with 100 mg sildenafil after re-education were classified as sildenafil non-responders. A com- bination of three vasodilator drugs, 1.25 mg papaverine, 0.4 mg phentolamine and 5 ug prostaglandin E1, was given by intracavernous injection before penile Doppler ultrasonography was carried out. The erectile response to intracavernous injection and vascular parameters including peak systolic velocity （PSV）, resistance index （RI）, end diastolic velocity （EDV） and cavernosa artery diameter （CD） were measured and the results between sildenafil nonresponders and responders were compared. Results： No statistical difference in vascular parameters measured by Doppler ultrasonography studies between non-responders and responders was noted. Sildenafil non-responders had a poorer penile rigidity response to intracavernous injection than responders （P 〈 0.05）. Among patients with adequate PSV （〉 30 cm/s） and abnormal EDV （〉 5 cm/s）, individuals in the non-responder group had fewer positive responses to intracavernous vasodilator injection than in the responder group （35.3% vs. 72.2%, P 〈 0.05）. Advanced age and comorbidity with diabetes mellitus were significantly associated with sildenafil non-response （P 〈 0.05）. Conclusion： Sildenafil non-responders were characterized by a poorer penile rigidity response to intracavernous injection and had an associated impaired veno-occlusive mechanism. Advanced age and comorbidity with diabetes mellitus were two common factors associated with non-response.
文摘To evaluate patient preferences for sildenafil citrate or tadalafil （PDE-5 inhibitors available for the treatment of erectile dysfunction [ED]） and assess potential reasons for these preferences. Methods： This open-label study was conducted on Korean men taking sildenafil, at least 6 weeks prior to study entry, for ED. Following screening, patients continued sildenafil treatment for 4 weeks, then after a 1-week washout period, switched to tadalafil for 8 weeks. Patients then continued with their treatment of choice during an extension phase. Psychosocial factors （time concern, spontaneity, sexual self-confidence） were evaluated using Psychological and Interpersonal Relation- ship Scales （PAIRS）, while timing of dose to sexual attempt patterns were assessed from patient diaries. Results： The present study enrolled 160 Korean men （mean age 55 years） with prior median sildenafil use of 585 days. During the extension phase, 73.7% of patients elected to take tadalafil, whereas 26.3% chose sildenafil （P 〈 0.001）. After switching from sildenafil to tadalafil, mean PAIRS time concern scores decreased from 2.54 to 2.42 （P = 0.002）, with no statistically significant differences observed between the sildenafil and tadalafil assessment phases in sexual spontaneity and self-confidence scores. Sexual attempts made 〉 4 h to 〈 36 h post-dose occurred in 4.5% of patients during the sildenafil assessment phase compared with 17.5% during the tadalafil assessment phase. Conclusion： After experiencing both sildenafil and tadalafil, the majority of patients exhibited a preference for tadalafil. This preference might be influenced by psychosocial factors, such as decreased time concerns, and a broader window of opportunity available for sexual activity.
文摘Aim： To assess the efficacy of sildenafil and continuous positive airway pressure （CPAP） in the treatment of concurrent erectile dysfunction （ED） with obstructive sleep apnea （OSA）, and to gauge the level of treatment satisfaction in patients and their partners. Methods： Forty men were treated for 12 weeks with sildenafil 100 mg （20 men） or CPAP during nighttime sleep （20 men）. Treatment efficacy was assessed by the rate of successful intercourse attempts, and satisfaction with treatment was assessed by patients＇ and partners＇ answers to question 1 of the Erectile Dysfunction Inventory of Treatment Satisfaction. Results： Under sildenafil, 128 of 249 （51.4%） intercourse attempts were successful; under CPAP, 51 of 193 （26.9%） attempts were successful （^cp 〈 0.001）. Erectile function was improved in both groups. After sildenafil and CPAP treatment, the mean International Index for Erectile Function domain scores were 14.3 and 10.8, respectively （^bp = 0.025）, compared to 7.8 and 7 at baseline, respectively. CPAP and sildenafil were well tolerated. Sporadic episodes of nasal dryness under CPAP and transient headache and flushing under sildenafil were not significant. Fifty percent of patients treated with sildenafil and 25% with CPAP were satisfied with the treatment, and their partners were equally satisfied. The satisfaction scores for both patients and partners under sildenafil were superior to those under CPAP （^cP 〈 0.002）. Conclusion： Both sildenafil 100 mg and CPAP, used separately, had positive therapeutic impact but sildenafil was superior. Patients and their partners were more satisfied with sildenafil for the treatment of ED. However, because of the high proportion of dissatisfied men and partners, new therapeutic agents or a combination of the two methods must be studied further.
文摘In vitro interaction of sildenafil citrate (SC) with bovine serum albumin (BSA) was investigated at two excitation wavelengths of BSA (280 nm and 293 nm) at two different temperatures (298 K and 308 K) by fluorescence emission spectroscopy. The study showed that quenching of BSA fluores-cence by sildenafil citrate was the result of formation BSA-SC complex with probable involvement of both tryptophan and tyrosine residues of BSA. Fluorescence quenching constant was determined from Stern-Volmer equation, and both static quenching and dynamic quenching were showed for BSA by SC at the conditions. Van’t Hoff equation was used to measure the thermodynamic parameters ΔG, ΔH, and ΔS at the temperatures which indicated that the hydrogen bond and the hydrophobic forces played major roles for BSA-SC complexation. The binding number (n) was found to be ≈1 indicating that one mole BSA bound with one mole SC. The binding affinity of SC to BSA was calculated at different temperatures. The binding constant was decreased with increasing temperatures indicating that stability of BSA-SC complex decreased with increasing temperatures.
文摘Aim： To determine the effect of sildenafil citrate on the nocturnal penile erections （i.e. time to onset, the duration of erection, and the interval between first and second erections） of healthy young men. Methods： Twenty-two potent men, 23-29 years old, were recruited for the study. All subjects completed three sessions over consecutive nights using the RigiScan monitoring device （Dacomed, Minneapolis, USA）. After a first night of adaptation, night 2 records were their baseline values, and on night 3 they received 100 mg of sildenafil citrate. Statistical comparisons were done between the second and third night data. Results： The mean time to onset of the first erection with sildenafil citrate was （34 ± 18） min, whereas it was （74 ± 24） min （P 〈 0.001） without sildenafil citrate. The number of erections observed during the first 5 h after sildenafil citrate medication was 3.6 ± 0.5 in contrast to 2.4 ± 0.5 with no medica- tion （P = 0.001）. The interval between first and second erections was shorter with sildenafil citrate： （52 ± 26） min vs. （85 ± 34） min （P = 0.01）. The duration of the last erection was statistically significantly longer with the sildenafil citrate： （64 ± 33） min vs. （42 ± 28） min （P 〈 0.01）. Conclusion： Healthy young men achieved erection within 34 min after sildenafil citrate administration, which is shorter than the 1 h interval proposed by the manufacturer. The interval between the first and second erections was shorter and the duration of the last nocturnal erection was longer.
基金Rigshospitalet,University of Copenhagen,The Laerdal Foundation for Acute MedicineSavvaerksejer Jeppe Juhl and wife Ovita Juhls Foundation+2 种基金The Novo Nordisk FoundationThe AP-Mфller Foundationan unrestricted grant from Pfizer,Denmark
文摘AIM： To investigate if sildenafil increases splanchnic blood flow and changes the hepatic venous pressure gradient （HVPG） in patients with cirrhosis. Phosphodiesterase type-5 inhibitors are valuable in the treatment of erectile dysfunction and pulmonary hypertension in patients with end-stage liver disease. However, the effect of phosphodiesterase type-5 inhibitors on splanchnic blood flow and portal hypertension remains essentially unknown. METHODS： Ten patients with biopsy proven cirrhosis （five females/five males, mean age 54：1：8 years） and an HVPG above 12 mmHg were studied after informed consent. Measurement of splanchnic blood flow and the HVPG during liver vein catheterization were done before and 80 min after oral administration of 50 mg sildenafil. Blood flow was estimated by use of indocyanine green clearance technique and Fick＇s principle, with correction for non-steady state. RESULTS： The plasma concentration of sildenafil was 222 ± 136 ng/mL 80 min after administration. Mean arterial blood pressure decreased from 77 ±7 mmHg to 66 ± 12 mmHg, P = 0.003, while the splanchnicblood flow and oxygen consumption remained unchanged at 1.14 ± 0.71 L/min and 2.3 ± 0.6 mmol/ min, respectively. Also the HVPG remained unchanged （18 ± 2 mmHg vs 16 ± 2 mmHg） with individual changes ranging from -8 mmHg to ±2 mmHg. In seven patients, HVPG decreased and in three it increased. CONCLUSION： In spite of arterial blood pressure decreases 80 min after administration of the phosphodiesterase type-5 inhibitor sildenafil, the present study could not demonstrate any clinical relevant influence on splanichnic blood flow, oxygen consumption or the HVPG.
文摘Aim: To examine the effect of sildenafil citrate on penile erection of male rhesus macaque. Methods: Twenty Macaca mulatta were divided into the sildenafil treated and the control groups of 10 animals each. The penile size, the corpus cavernosal electromyogram (EMG) and the intra-corpus cavernosal pressure (ICP) were determined. Results: The diameter of penis and the ICP were significantly increased and the corpus cavernosal EMG significantly reduced in the sildenafil group. Conclusion: Sildenafil citrate increases the penile size and ICP and reduces the corpus cavernosal EMG in male rhesus macaque.
文摘Aim: To investigate the reasons for discontinuations of sildenafil after the successful restoration of erectile function. Methods: One hundred fifty six patients, whose scores of erectile function domain of the 15-item International Index of Erectile Function (IIEF) increased to 26 or more after sildenafil medication, were included in this study. Six-months after the first sildenafil prescription, compliance to medication and the reason for discontinuity were reviewed by chart or surveyed by telephone. Results: Fifty-four (34.6%) of the 156 successfully treated patients discontinued sildenafil medication. The r easons for discontinuance were shortcomings in the partners' or patients' emotional readiness for the restoration of sexual life after long-term abstinence (37.0%), fear of possible side effects (18.5 %), recovery of spontaneous erection (14.8 %), postponement of ED treatment because of co morbid disease treatment (11.1%), unwillingness to accept drug-dependent erection (7.4%), high drug cost (3.7%), unacceptability of planned sexual activity (3.7%) and lack of sexual interesi (3.7%). Conclusion: The reasons for discontinuing sildenafil medication were primarily emotional or relationship-oriented, which indicates that simple recovery of a rigid erection is insufficient to restore sexual activity. More education about the effects of drug and the counseling of both partners is recommended to promote the successful recovery of sexual activity.
文摘<abstract>Aim: To determine the ultrastructural effects of sildenafil on the female genital organs. Methods: Twenty female cycling Wistar albino rats weighing 250±20 g were randomly divided into two groups of 10 each. Rats of one group were gavaged with 0.5 mg·kg-1·d-1 of sildenafil 3 days in a week for 4 weeks and the other served as the controls. After cessation of treatment animals were sacrificed by cervical dislocation under methoxyflurane anaesthesia. The clitoris, vagina, uterus and bartholin glands were taken at the estrous and were fixed with 10 % formalin solution for light microscopy and 2.5 % glutaraldehyde and osmic acid for electron microscopy. Results: Under the light microscope, the fibrocollageous tissue was found increased, the capillaries enlarged and the connecting tissue elements increased in the corpus cavernosum in the treated group. On electron microscopy, increased connective tissue, fibroblasts with notched nucleus, shorten immature collagen fibers without striation were seen. Abundant foldings and penetration with collagen bundles were observed in the basal membrane. Large connection complexes, especially gap junctions among the wide capillary endothelial cells were observed. Conclusion: There are evident histological changes due to sildenafil citrate in female rat corpus cavernosum. The clitoris and bartholin glands were the most effected organs. While the histopathological changes of clitoral tissue could be expected, an increase in the mass of bartholin gland was surprised.
文摘Sildenafil citrate is a potent and selective phosphodiesterase-5inhibitor. It is effectively used in the treatment of erectile dysfunction and pulmonary arterial hypertension. The drug is rapidly absorbed and pharmacologically acts within30 min to 1 h after oral administration. However, it has a relatively low absolute bioavailability of 41%because its limited solubility in water is the major problem (1)To improve the oral bioavailability of poorly water-soluble drugs.
文摘Dear Editor,Sildenafil citrate（Viagra;Pfizer Pharmaceuticals,New York,NY,USA）,a selective inhibitor of phosphodiesterase type 5（PDE-5）,is widely used for erectile dysfunction.Its clinical recommended dosage is 25 to 100 mg per day.
