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
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
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 to...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.The most common ocular side-effects are blurred vision展开更多
Sildenafil citrate is a highly selective phosphodiesterase-5(PDE-5)inhibitor.It is used for treatment of erectile dysfunction and pulmonary hypertension[1].Sildenafil citrate is categorized in BCS class 2 so it is dev...Sildenafil citrate is a highly selective phosphodiesterase-5(PDE-5)inhibitor.It is used for treatment of erectile dysfunction and pulmonary hypertension[1].Sildenafil citrate is categorized in BCS class 2 so it is developed as a citrate salt to increase water solubility(4.1 mg/mL)[2].The conventional product has been developed as a tablet dosage form.It is rapidly absorbed after oral administration,but gives a relatively low oral bioavailability of about 40%and late onset of action[2].Dry foam formulation technology is an alternative approach to overcome such a problem.展开更多
Sex-related cardiovascular arrest is a rare event occurring typically among middle-aged men with cardiovascular risk.[1,2]The main etiologies of sex-related sudden cardiovascular arrest are acute coronary syndrome and...Sex-related cardiovascular arrest is a rare event occurring typically among middle-aged men with cardiovascular risk.[1,2]The main etiologies of sex-related sudden cardiovascular arrest are acute coronary syndrome and subarachnoid hemorrhage and,to a lesser extent,chronic coronary artery disease and structural non-ischemic heart disease.[3]Coital angina that occurs during the minutes or hours after sexual activity represents<5%of all anginal attacks and it is rare in patients who do not have angina during strenous physical exertion.[4]Moreover,sexual activity is the cause of<1%of all acute myocardial infarctions.[5]Sudden death during sexual intercourse is reported with an incidence of 0.6%–1.7%.[6–8]The investigation of sudden death related to sexual activity may be difficult as it may be regarded as shameful or disgraceful to the family members and,especially to the remaining partner.Because of rarity of epidemiological data,considerable bias in the investigation of sudden death related to sexual activity has to be expected.[9–11]Extramarital sexual activity with younger partner and unfamiliar setting seems to represent risk factor as well as excessive food and alcohol consumption.[7]展开更多
Sildenafil and bosentan are often co-administered for pulmonary arterial hypertension (PAH) treatment. The plasma concentration of sildenafil can be decreased by half if co-administered with bosentan. Many patients ta...Sildenafil and bosentan are often co-administered for pulmonary arterial hypertension (PAH) treatment. The plasma concentration of sildenafil can be decreased by half if co-administered with bosentan. Many patients take these agents simultaneously in the morning and the evening. The aim of this study was to examine the pharmacokinetics of sildenafil which was interfered with bosentan administration to ascertain whether these agents should be given concomitantly or separately. A two-way crossover study was conducted in 6 PAH patients with combination therapy of sildenafil and bosentan. Participants underwent the sequence of treatment phases: phase S (sildenafil administered 3 h before bosen-tan);phase B (bosentan administered 3 h before sildenafil);and phase C (administered concomitantly). Blood samples were collected on the last day of each phase. There was no significant difference in maximum plasma concentration or area under the plasma concentration-time curve (AUC0-8) between phase C and phase S (95.5 ± 24.8 vs. 72.9 ± 40.9 (p = 0.07), 209.7 ± 81.8 vs. 180.2 ± 126.4 (p = 0.24), respectively) or between phases C and B (87.8 ± 42.0 vs. 99.6 ± 33.9 (p = 0.59), 197.2 ± 88.2 vs. 240.7 ± 121.8 (p = 0.19), respectively) (ng/mL, mean ± standard deviation). Large intra-and inter-individual variability in sildenafil concentration was noted. The timing of administration of sildenafil and bosentan does not significantly influence the plasma concentration of sildenafil. Physicians do not need to be overly concerned about the timing of administration of these drugs to maximize the sildenafil concentration.展开更多
Objectives: Sildenafil citrate (Viagra) is widely used as an aphrodisiac drug and for the treatment of erectile dysfunction. The present study was planned to study the morphological changes that might occur in the fro...Objectives: Sildenafil citrate (Viagra) is widely used as an aphrodisiac drug and for the treatment of erectile dysfunction. The present study was planned to study the morphological changes that might occur in the frontal cortex of the adult rat in response to chronic intake of Viagra and discover whether these changes are reversible or irreversible. Material and Methods: Forty adult male rats were used where they were classified into three groups: A control group (10 rats), B experimental treated group (20 rats), and C recovery group (10 rats). The treated and recovery groups received therapeutic dose of Viagra for 30 days. The control and the treated group were sacrificed at the first day after the designated period (30 days), the recovery group was sacrificed two weeks after the end of experiment. Results: The pyramidal cell neurons are little in number;some of them are atrophic, degenerated. Their cytoplasm showed varied degree of cellular degenerative changes with vaculation of their myelinated axons. Pyramidal neurons of recovery animals showed nearly complete recovery. Conclusion: Chronic intake of Viagra produced reversible morphological changes in pyramidal neurons of the frontal cortex of adult male rats.展开更多
<strong>Objective</strong><strong>:</strong><span style="font-family:""><span style="font-family:Verdana;"> To compare between the efficacy of the use of or...<strong>Objective</strong><strong>:</strong><span style="font-family:""><span style="font-family:Verdana;"> To compare between the efficacy of the use of oral sildenafil plus low dose aspirin versus the use of oral low dose aspirin alone in pregnancy as preventive measure in women at risk for preeclampsia (PE). </span><b><span style="font-family:Verdana;">Design: </span></b><span style="font-family:Verdana;">A randomized clinical trial. </span><b><span style="font-family:Verdana;">Setting: </span></b><span style="font-family:Verdana;">Outpatient Obstetric clinic of Ain Shams University Maternity Hospital. </span><b><span style="font-family:Verdana;">Population or sample: </span></b><span style="font-family:Verdana;">Women at gestational age of </span></span><span style="font-family:""><span style="font-family:Verdana;">≤</span><span><span style="font-family:Verdana;">16 weeks who at risk for PE between June 2018 and June 2019. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> Participants were randomly allocated into two groups: Group I Included 200 women who received a 25 mg tablet of oral sildenafil citrate tid until delivery plus 100 mg tablet of aspirin orally once daily until gestational age of 36 weeks, Group II Included 200 women who received a 100 mg tablet of aspirin orally once daily until gestational age of 36 weeks. </span><b><span style="font-family:Verdana;">Main Outcome Measures: </span></b><span style="font-family:Verdana;">Incidence of preeclampsia diagnosed per ACOG criteria. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> The incidence of PE in both groups showed no statistically significant difference. The incidence of PE in the first group is 11.0%, and it is 12.0% in the second group (p-value 0.754). </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> The addition of sildenafil citrate to low dose aspirin had no impact on the prevention of preeclampsia for women at risk of PE, in addition, sildenafil did not improve maternal and fetal outcomes.</span></span></span>展开更多
Purpose: To evaluate the efficacy and safety of sildenafil in orodispersable tablets of 50 mg vs. placebo in men with erectile dysfunction (ED). Methods: A blind, comparative, placebo controlled, randomized study was ...Purpose: To evaluate the efficacy and safety of sildenafil in orodispersable tablets of 50 mg vs. placebo in men with erectile dysfunction (ED). Methods: A blind, comparative, placebo controlled, randomized study was developed in 106 patients with ED. They randomly received sildenafil orodispersable 50 mg (Group I) or placebo (Group II) 3 times per week, 1 hour before sexual activity, during 4 weeks. The efficacy was evaluated by IIEF-5 and the adverse events (AE) by poll. Results: After 4 weeks a percentage improvement of the ED was observed in Group I patients 44% of whom became without ED vs. 2% of Group II, with an additional statistical significant improvement evidenced respect to the placebo in the IIEF-5 score from 13.7 ± 4.9 to 19.9 ± 4.4 vs. 13.1 ± 4.0 to 17.8 ± 4.9 in the placebo group, Confidence Interval (CI95%): 19.90 vs. 13.98, respectively, p Conclusions: Sildenafil was superior to placebo, substantially improved the IIEF-5 scores, showing a statistical significant therapeutic response in the ED treatment and it was safe and well tolerated.展开更多
Background:Hypoxic-ischemic injuries following birth asphyxia often lead to long-term neurological sequelae,including visual impairments,due to cortical and retinal injuries in affected neonates.Although treatment wit...Background:Hypoxic-ischemic injuries following birth asphyxia often lead to long-term neurological sequelae,including visual impairments,due to cortical and retinal injuries in affected neonates.Although treatment with sildenafil has been shown to improve retinal function following term neonatal asphyxia,the underlying mode of action explaining this improvement remains yet to be elucidated.Our goal is to determine the impact of sildenafil on retinal neurons and glial cells following hypoxic-ischemic injury.Methods:Neonatal hypoxia-ischemia(HI)was induced in male Long-Evans rat pups at postnatal day 10(P10)by left common carotid ligation followed by 2-hour exposure to 8%oxygen.12 hours following HI,animals were randomly administered 0(vehicle),2,10 or 50 mg/kg of sildenafil for 7 consecutive days.At P30,rats were sacrificed and their eyes were extracted.Immunohistochemistry was performed to examine retinal ganglion cells(Brn3a),bipolar cells(Chx10),astrocytes(GFAP)and microglia(Iba1)in order to assess the neuronal count and the inflammatory response in the retina following HI and the impact of the sildenafil treatment.In addition,the ratio of activated to non-activated Muller cells was assessed by co-staining Nestin and GS respectively.Results:In the retina,HI caused a decrease in the number of retinal ganglion cells and bipolar cells,as well as an increase in inflammation marked by an increase in the number of astrocytes and an increase in the ratio of activated to non-activated Muller cells.Sildenafil treatment restored the number of retinal ganglion cells and bipolar cells,as well as reduced neuroinflammation by decreasing the number of astrocytes and the number of activated Muller cells.Conclusions:Sildenafil seems to improve retinal injuries by reestablishing retinal neuron numbers back to sham levels and modulating inflammation following HI.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.The most common ocular side-effects are blurred vision
文摘Sildenafil citrate is a highly selective phosphodiesterase-5(PDE-5)inhibitor.It is used for treatment of erectile dysfunction and pulmonary hypertension[1].Sildenafil citrate is categorized in BCS class 2 so it is developed as a citrate salt to increase water solubility(4.1 mg/mL)[2].The conventional product has been developed as a tablet dosage form.It is rapidly absorbed after oral administration,but gives a relatively low oral bioavailability of about 40%and late onset of action[2].Dry foam formulation technology is an alternative approach to overcome such a problem.
文摘Sex-related cardiovascular arrest is a rare event occurring typically among middle-aged men with cardiovascular risk.[1,2]The main etiologies of sex-related sudden cardiovascular arrest are acute coronary syndrome and subarachnoid hemorrhage and,to a lesser extent,chronic coronary artery disease and structural non-ischemic heart disease.[3]Coital angina that occurs during the minutes or hours after sexual activity represents<5%of all anginal attacks and it is rare in patients who do not have angina during strenous physical exertion.[4]Moreover,sexual activity is the cause of<1%of all acute myocardial infarctions.[5]Sudden death during sexual intercourse is reported with an incidence of 0.6%–1.7%.[6–8]The investigation of sudden death related to sexual activity may be difficult as it may be regarded as shameful or disgraceful to the family members and,especially to the remaining partner.Because of rarity of epidemiological data,considerable bias in the investigation of sudden death related to sexual activity has to be expected.[9–11]Extramarital sexual activity with younger partner and unfamiliar setting seems to represent risk factor as well as excessive food and alcohol consumption.[7]
文摘Sildenafil and bosentan are often co-administered for pulmonary arterial hypertension (PAH) treatment. The plasma concentration of sildenafil can be decreased by half if co-administered with bosentan. Many patients take these agents simultaneously in the morning and the evening. The aim of this study was to examine the pharmacokinetics of sildenafil which was interfered with bosentan administration to ascertain whether these agents should be given concomitantly or separately. A two-way crossover study was conducted in 6 PAH patients with combination therapy of sildenafil and bosentan. Participants underwent the sequence of treatment phases: phase S (sildenafil administered 3 h before bosen-tan);phase B (bosentan administered 3 h before sildenafil);and phase C (administered concomitantly). Blood samples were collected on the last day of each phase. There was no significant difference in maximum plasma concentration or area under the plasma concentration-time curve (AUC0-8) between phase C and phase S (95.5 ± 24.8 vs. 72.9 ± 40.9 (p = 0.07), 209.7 ± 81.8 vs. 180.2 ± 126.4 (p = 0.24), respectively) or between phases C and B (87.8 ± 42.0 vs. 99.6 ± 33.9 (p = 0.59), 197.2 ± 88.2 vs. 240.7 ± 121.8 (p = 0.19), respectively) (ng/mL, mean ± standard deviation). Large intra-and inter-individual variability in sildenafil concentration was noted. The timing of administration of sildenafil and bosentan does not significantly influence the plasma concentration of sildenafil. Physicians do not need to be overly concerned about the timing of administration of these drugs to maximize the sildenafil concentration.
文摘Objectives: Sildenafil citrate (Viagra) is widely used as an aphrodisiac drug and for the treatment of erectile dysfunction. The present study was planned to study the morphological changes that might occur in the frontal cortex of the adult rat in response to chronic intake of Viagra and discover whether these changes are reversible or irreversible. Material and Methods: Forty adult male rats were used where they were classified into three groups: A control group (10 rats), B experimental treated group (20 rats), and C recovery group (10 rats). The treated and recovery groups received therapeutic dose of Viagra for 30 days. The control and the treated group were sacrificed at the first day after the designated period (30 days), the recovery group was sacrificed two weeks after the end of experiment. Results: The pyramidal cell neurons are little in number;some of them are atrophic, degenerated. Their cytoplasm showed varied degree of cellular degenerative changes with vaculation of their myelinated axons. Pyramidal neurons of recovery animals showed nearly complete recovery. Conclusion: Chronic intake of Viagra produced reversible morphological changes in pyramidal neurons of the frontal cortex of adult male rats.
文摘<strong>Objective</strong><strong>:</strong><span style="font-family:""><span style="font-family:Verdana;"> To compare between the efficacy of the use of oral sildenafil plus low dose aspirin versus the use of oral low dose aspirin alone in pregnancy as preventive measure in women at risk for preeclampsia (PE). </span><b><span style="font-family:Verdana;">Design: </span></b><span style="font-family:Verdana;">A randomized clinical trial. </span><b><span style="font-family:Verdana;">Setting: </span></b><span style="font-family:Verdana;">Outpatient Obstetric clinic of Ain Shams University Maternity Hospital. </span><b><span style="font-family:Verdana;">Population or sample: </span></b><span style="font-family:Verdana;">Women at gestational age of </span></span><span style="font-family:""><span style="font-family:Verdana;">≤</span><span><span style="font-family:Verdana;">16 weeks who at risk for PE between June 2018 and June 2019. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> Participants were randomly allocated into two groups: Group I Included 200 women who received a 25 mg tablet of oral sildenafil citrate tid until delivery plus 100 mg tablet of aspirin orally once daily until gestational age of 36 weeks, Group II Included 200 women who received a 100 mg tablet of aspirin orally once daily until gestational age of 36 weeks. </span><b><span style="font-family:Verdana;">Main Outcome Measures: </span></b><span style="font-family:Verdana;">Incidence of preeclampsia diagnosed per ACOG criteria. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> The incidence of PE in both groups showed no statistically significant difference. The incidence of PE in the first group is 11.0%, and it is 12.0% in the second group (p-value 0.754). </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> The addition of sildenafil citrate to low dose aspirin had no impact on the prevention of preeclampsia for women at risk of PE, in addition, sildenafil did not improve maternal and fetal outcomes.</span></span></span>
文摘Purpose: To evaluate the efficacy and safety of sildenafil in orodispersable tablets of 50 mg vs. placebo in men with erectile dysfunction (ED). Methods: A blind, comparative, placebo controlled, randomized study was developed in 106 patients with ED. They randomly received sildenafil orodispersable 50 mg (Group I) or placebo (Group II) 3 times per week, 1 hour before sexual activity, during 4 weeks. The efficacy was evaluated by IIEF-5 and the adverse events (AE) by poll. Results: After 4 weeks a percentage improvement of the ED was observed in Group I patients 44% of whom became without ED vs. 2% of Group II, with an additional statistical significant improvement evidenced respect to the placebo in the IIEF-5 score from 13.7 ± 4.9 to 19.9 ± 4.4 vs. 13.1 ± 4.0 to 17.8 ± 4.9 in the placebo group, Confidence Interval (CI95%): 19.90 vs. 13.98, respectively, p Conclusions: Sildenafil was superior to placebo, substantially improved the IIEF-5 scores, showing a statistical significant therapeutic response in the ED treatment and it was safe and well tolerated.
文摘Background:Hypoxic-ischemic injuries following birth asphyxia often lead to long-term neurological sequelae,including visual impairments,due to cortical and retinal injuries in affected neonates.Although treatment with sildenafil has been shown to improve retinal function following term neonatal asphyxia,the underlying mode of action explaining this improvement remains yet to be elucidated.Our goal is to determine the impact of sildenafil on retinal neurons and glial cells following hypoxic-ischemic injury.Methods:Neonatal hypoxia-ischemia(HI)was induced in male Long-Evans rat pups at postnatal day 10(P10)by left common carotid ligation followed by 2-hour exposure to 8%oxygen.12 hours following HI,animals were randomly administered 0(vehicle),2,10 or 50 mg/kg of sildenafil for 7 consecutive days.At P30,rats were sacrificed and their eyes were extracted.Immunohistochemistry was performed to examine retinal ganglion cells(Brn3a),bipolar cells(Chx10),astrocytes(GFAP)and microglia(Iba1)in order to assess the neuronal count and the inflammatory response in the retina following HI and the impact of the sildenafil treatment.In addition,the ratio of activated to non-activated Muller cells was assessed by co-staining Nestin and GS respectively.Results:In the retina,HI caused a decrease in the number of retinal ganglion cells and bipolar cells,as well as an increase in inflammation marked by an increase in the number of astrocytes and an increase in the ratio of activated to non-activated Muller cells.Sildenafil treatment restored the number of retinal ganglion cells and bipolar cells,as well as reduced neuroinflammation by decreasing the number of astrocytes and the number of activated Muller cells.Conclusions:Sildenafil seems to improve retinal injuries by reestablishing retinal neuron numbers back to sham levels and modulating inflammation following HI.
