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Biomedical subjects

D R Nelson

Publications and source records attributed to D R Nelson.

At least 55 records · Page 3Linked to original sources

Interleukin 10 treatment reduces fibrosis in patients with chronic hepatitis C: a pilot trial of interferon nonresponders.

BACKGROUND & AIMS: Interleukin (IL)-10 is a cytokine that down-regulates the proinflammatory response and has a modulatory effect on hepatic fibrogenesis. The aim of this study was to determine the effect of IL-10 on hepatic injury in patients with chronic hepatitis C. METHODS: Twenty-four patients with chronic hepatitis C who had not previously responded to interferon-based therapy were enrolled in a randomized, double-blinded 2-dose trial in which they received either 4 or 8 microgram/kg IL-10 subcutaneously daily for 90 days. Liver biopsies were performed before and at the end of therapy. RESULTS: IL-10 was well tolerated with 22 patients completing the study. Serum ALT levels normalized in 19 of 22 patients by the end of therapy and were sustained in 5 of 22. Hepatic inflammation decreased in 19 of 22 patients, with 11 having a decrease by >/=2. Fibrosis decreased in 14 of 22 patients (mean change, 3.6-2.6; P = 0.001). There was no change in serum HCV RNA levels. IL-10 therapy was associated with changes in serological markers, suggesting a reduction of immune response and fibrogenesis. CONCLUSIONS: IL-10 therapy is safe and well tolerated in patients with chronic hepatitis C. Although it has no apparent antiviral activity, IL-10 normalizes serum ALT levels, improves liver histology, and reduces liver fibrosis in a large proportion of patients receiving treatment. Therefore, IL-10 may have therapeutic potential in patients with chronic hepatitis C patients who do not respond to interferon-based therapy.

Alanine Transaminase↗

Seminal oxidative stress in patients with chronic prostatitis.

OBJECTIVES: An association between prostatitis and male infertility has been suspected, yet is poorly understood. Prostatitis is often associated with granulocytes in the prostatic fluid that generate reactive oxygen species (ROS), known to impair male fertility. We compared ROS, the total antioxidant capacity (TAC), and a novel index of oxidative stress (ROS-TAC score) in patients with chronic prostatitis and in healthy controls. METHODS: Semen specimens from 36 men with chronic prostatitis (National Institutes of Health category IIIa), 8 men with prostatodynia (National Institutes of Health category IIIb), and 19 controls attending our urologic clinic were examined according to the World Health Organization criteria. Leukocytospermia was measured by the Endtz test (myeloperoxidase assay). ROS and TAC production was measured by chemiluminescence assay. A composite ROS-TAC score was also calculated in patients and controls. RESULTS: The sperm concentration, percentage of motility, and morphology among the groups did not differ. The mean +/- standard error log-transformed ROS level was significantly higher in patients with leukocytospermia (3.2 +/- 0.6) than in patients without leukocytospermia (1.8 +/- 0.2; P = 0.04) and controls (1.3 +/- 0.3, P = 0.01). TAC was significantly lower in patients with or without leukocytospermia (859.69 +/- 193.0 and 914.9 +/- 65.2, respectively) than in controls (1653.98 +/- 93.6, P = 0.001). The mean ROS-TAC score of controls (50.0 +/- 4.1) was significantly higher than those of patients with chronic prostatitis and leukocytospermia (8.2 +/- 9.2) and those without leukocytospermia (34.2 +/- 2.9; P <0.001). CONCLUSIONS: Men with chronic prostatitis or prostatodynia have seminal oxidative stress, irrespective of their leukocytospermia status. These observations may help shed light on the long-standing controversy surrounding prostatitis and infertility.

Antioxidants↗

Waxes and lipids associated with the external waxy structures of nymphs and pupae of the giant whitefly, Aleurodicus dugesii.

The nymphs and pupae of the giant whitefly, Aleurodicus dugesii, produce large quantities of external lipids, both as waxy particles and as waxy filaments. The nymphs and pupae extrude filaments from two dorsal rows of five pores each. Filaments can attain lengths of 5-8 cm. The external lipids of nymphs and pupae consist largely of long-chain aldehydes, alcohols, acetate esters and wax esters. Hydrocarbons are minor components. Soon after hatching, the nymph produced an unidentified waxy fringe extruded laterally from its margin. After molting to the second instar, long, hollow, waxy filaments were produced by the immature stages. The major lipid class associated with the filaments was saturated wax esters (89%), mainly C44, C46 and C60. Associated with formation of the filaments were waxy particles in the shape of curls, which peeled off of the extruding filaments. Similar but more tubular-shaped curls were also produced by numerous lateral pores so that, eventually, the curls completely camouflaged the nymph. The major lipid class of the curls was wax esters (50%), mainly C44 and C46. The cuticular surface lipids of the nymphs were mainly long-chain aldehydes (43%) and wax esters (27%). Unsaturated fatty acid moieties constituted 2 and 19% of the wax esters of curls and nymph cuticular surface lipids, respectively. The major lipid classes of pupae and of their palisade were long-chain aldehydes and alcohols. No unsaturated wax esters were detected in the filaments, but 30% of pupal and 21% of palisade surface wax esters were unsaturated in their fatty acid moieties, 16:1, 18:1 and 20:1.

Animals↗

The effect of patient and semen characteristics on live birth rates following intrauterine insemination: a retrospective study.

PURPOSE: To identify characteristics of female patients and of semen that were associated with live birth following intrauterine insemination (IUI). METHODS: Retrospective review of medical and laboratory results from 533 women who underwent IUI with partner's sperm from 1993 through 1995. RESULTS: Among 1728 cycles, 116 (6.7%) resulted in live deliveries. Among the 38 patient and semen variables analyzed, only 3 were associated with successful IUI outcome: female age < 37.7 years at the time of treatment (P = 0.02); the absence of any corrective pelvic surgery (P < 0.001); and postwash sperm motility (P = 0.006). Couples with none of these three risk factors achieved per-cycle pregnancy rates of 12.4%. Women with two risk factors (age and pelvic surgery) achieved per-cycle pregnancy rates of 4.6% when sperm had good postwash motility. No pregnancies were achieved when low postwash motility was combined with any other risk factor. CONCLUSIONS: Advanced female age, poor postwash sperm motility, and a history of corrective pelvic surgery are significant risk factors for poor IUI success rates. Poor postwash sperm motility in combination with either of these other two risk factors resulted in no successful pregnancies.

Adult↗

Effect of clinical and semen characteristics on efficacy of ovulatory stimulation in patients undergoing intrauterine insemination.

PURPOSE: We measured the effect of ovulatory stimulation (OS) upon intrauterine insemination (IUI) success rates, particularly among patients with risk factors for IUI failure. METHODS: Retrospective review of medical and laboratory results from 512 patients who underwent 1576 cycles of IUI with partner's sperm over a 3 year period. Data were collected on 3 risk factors for IUI failure (advanced female age > 37.7 years, prior corrective pelvic surgery, and poor post-wash sperm motility), and on method of OS (none, clomiphene citrate, or gonadotropin). RESULTS: Patients who underwent OS had significantly higher pregnancy rates (7.6%) than those who did not (4.7%, p = 0.02). However, when patients were stratified by their risk factors, OS made a significant difference only for patients without risk factors. These patients had a 15.5% per cycle pregnancy rate with OS, compared to 7.9% in unstimulated IUI cycles (p = 0.04). CONCLUSIONS: Ovulatory stimulation doubles IUI pregnancy rates among young patients without a prior pelvic surgery and with good post-wash semen quality. The benefit of OS for patients with risk factors for IUI failure is unclear. These patients should be counseled that their chances for success with IUI are limited, with or without OS.

Adult↗

Head computed tomography in medical intensive care unit patients: clinical indications.

OBJECTIVE: To assess whether clinical variables might be useful in selecting patients who will have an acute intracranial abnormality seen in head computed tomographic scans (HCT). DESIGN: Retrospective study. SETTING: Medical intensive care unit (MICU) in a tertiary teaching hospital. MEASUREMENTS: Medical records of patients admitted to the MICU who underwent HCT between January 1, 1994, and December 31, 1995, were reviewed. Patients with acute intracranial abnormalities (HCT-positive) and those without new acute findings (HCT-negative) were compared on various clinical variables, including demographics, indications for obtaining the HCT (mental status change, neurologic deficit, fever, seizures), coagulation profiles, when the HCT was performed (at admission or after admission), and ordering physician. MAIN RESULTS: Of 297 HCTs obtained in 230 patients, 37% (109/297) were positive. When the clinical variables were examined univariately, only the presence of a neurologic deficit (70% vs. 37%; difference, 33%; p < .001) differed significantly between positive and negative HCTs. Multivariate analysis confirmed that only the frequency of a new neurologic deficit differed significantly in the two groups (p < .001; odds ratio, 3.9; 95% confidence interval, 2.3-6.4). In patients without neurologic deficits, only the presence of seizures was associated with a positive HCT (p < .01: logistic regression). The presence of either neurologic deficit or seizures best predicted a positive HCT: sensitivity 0.81, specificity 0.53, positive predictive value 0.50, and negative predictive value 0.83. CONCLUSION: Among MICU patients, the presence of either neurologic deficit or seizures is associated with the presence of an acute intracranial abnormality seen in HCT, but the association is not powerful enough to reliably depend on these clinical variables to select patients for HCTs in the MICU.

APACHE↗

Emergency department workplace interruptions: are emergency physicians "interrupt-driven" and "multitasking"?

OBJECTIVE: Although interruptions have been shown in aviation and other work settings to result in error with serious and sometimes fatal consequences, little is known about interruptions in the emergency department (ED). The authors conducted an observational, time-motion task-analysis study to determine the number and types of interruptions in the ED. METHODS: Emergency physicians were observed in three EDs located in an urban teaching hospital, a suburban private teaching hospital, and a rural community hospital. A single investigator followed emergency staff physicians for 180-minute periods and recorded tasks, interruptions, and breaks-intask. An "interruption" was defined as any event that briefly required the attention of the subject but did not result in switching to a new task. A "break-intask" was defined as an event that required the attention of the physician for more than 10 seconds and subsequently resulted in changing tasks. RESULTS: The mean (+/-SD) total number of patients seen at all three sites during the 180-minute study period was 12.1 +/- 3.7 patients (range 5-20). Physicians performed a mean of 67.6 +/- 15.7 tasks per study period. The mean number of interruptions per 180-minute study period was 30.9 +/- 9.7 and the mean number of breaks-in-task was 20.7 +/- 6.3. Both the number of interruptions (r = 0.63; p < 0.001) and the number of breaks-in-task (r = 0.56; p < 0.001) per observation period were positively correlated with the average number of patients simultaneously managed. CONCLUSIONS: Emergency physicians are "interruptdriven." Emergency physicians are frequently interrupted and many interruptions result in breaks-in-task.

Adult↗

Cell cycle arrest and differential gene expression in HT-29 cells exposed to an aqueous garlic extract.

Epidemiological data show an inverse correlation between garlic consumption and the risk for colon cancer. To examine this relationship, HT-29 human adenocarcinoma cells were cultured in the presence and absence of an aqueous garlic extract. Garlic treatment resulted in a fraction of cells detaching from the culture flasks. These cells remained viable. Flow cell cytometry showed that untreated cells exhibited a normal distribution among phases of the cell cycle, with 12% of cells at the G2/M boundary. Of the garlic-treated cells remaining attached to the flask, 27% were present at the G2/M boundary. Treated cells that detached from the flask were found almost exclusively (89%) at the G2/M boundary. RNA fingerprinting and microarray analysis showed that expression of the gene for menin was twice as high in control cells as in detached treated cells. In contrast, expression of genes for epidermal growth factor receptor and integrin-alpha6 was nearly twice as high in detached treated cells as in control cells. These changes in gene expression were consistent with an arrest of the cell cycle at the G2/M boundary. Garlic's arrest of the cell cycle in human adenocarcinoma cells may explain in part its anticarcinogenic properties.

Adenocarcinoma↗

Complement-mediated killing of Borrelia burgdorferi by nonimmune sera from sika deer.

Various species of cervid deer are the preferred hosts for adult, black-legged ticks (Ixodes scapularis and Ixodes pacificus) in the United States. Although frequently exposed to the agent of Lyme disease (Borrelia burgdorferi), these animals, for the most part, are incompetent as transmission reservoirs. We examined the borreliacidal activity of normal and B. burgdorferi-immune sera from sika deer (Cervus nippon) maintained in a laboratory setting and compared it to that of similar sera from reservoir-competent mice and rabbits. All normal deer sera (NDS) tested killed > 90% of B. burgdorferi cells. In contrast, normal mouse and rabbit sera killed < or = 22% of the Borrelia. Anti-B. burgdorferi antibodies could not be detected in any normal sera by indirect fluorescent antibody assay (IFA). Sera collected from deer 6 wk after exposure to B. burgdorferi by tick feeding exhibited IFA titers of 1:256, whereas sera from mice and rabbits similarly exposed had titers of > 1:1,024. Heat treatment (56 C, 30 min) of NDS reduced borreliacidal activity, with < 20% of the B. burgdorferi cells killed, suggesting complement-mediated killing. The chelators EGTA and EDTA were used to block the classical or both the classical and alternative complement pathways, respectively. Addition of 10 mM EGTA to NDS had a negligible effect on borreliacidal activity, with > 90% of the cells killed. Addition of 10 mM EDTA reduced the killing to approximately 30%, whereas the addition of Mg2+ (10 mM) restored borreliacidal activity to NDS. The addition of zymosan A, an activator of the alternative pathway, increased the survival of B. burgdorferi cells to approximately 80% in NDS. These data suggest that the alternative complement activation pathway plays a major role in the borreliacidal activity of NDS. Additionally, 10 mM EGTA had almost no effect on the killing activity of B. burgdorferi-exposed deer sera, suggesting that the classical pathway is not involved in Borrelia killing, even in sera from B. burgdorferi-exposed deer.

Animals↗

Infectious necrotizing enteritis and mortality caused by Vibrio carchariae in summer flounder Paralichthys dentatus during intensive culture.

An epizootic causing mortality among cultured summer flounder Paralichthys dentatus occurred in summer of 1998 at a land-based facility on Narragansett Bay, Rhode Island, USA. The disease, flounder infectious necrotizing enteritis (FINE), was characterized by reddening around the anal area, distended abdomens filled with opaque serosanguineous fluid, enteritis and necrosis of the posterior intestine. In extreme cases of the disease, the posterior intestine was detached from the anus and was observed coming out the vent. The intestine of individuals that recovered from the disease ended in a blind-sac; the abdomens of these fish were distended, due to food and water inside the intestinal blind-sac. A bacterium was isolated from ascites fluid and kidney of moribund flounder and identified as the causative agent in challenge experiments. The pathogen was identified as Vibrio carchariae by morphological and biochemical characteristics and sequence of the 16S rRNA. The LD50 estimate was 5 x 10(5) colony-forming units injected intraperitoneally into 100 to 200 g summer flounder.

Abdomen↗

A second CYP26 P450 in humans and zebrafish: CYP26B1.

A new P450 gene has been found in humans. It has 44% sequence identity to CYP26A1 from human and mouse, which places it in a new subfamily, CYP26B. There is only one human EST from a retinal library (AA012833) that matches the coding region. No homologous ESTs are found in mouse. A zebrafish EST AI721901 shows 68% identity to the human protein. This zebrafish EST is only 41% identical to the zebrafish CYP26A1 protein sequence, so it represents the homolog of the human CYP26B1 sequence. It is not known if this gene product will act on all-trans-retinoic acid like the CYP26A1 protein or if it might hydroxylate the 9-cis- or 13-cis-retinoic acid isoforms not recognized by CYP26A1. The importance of the CYP26A1 P450 in mouse and zebrafish development flags the CYP26B1 gene as a potential developmental gene.

Amino Acid Sequence↗

Cytochrome P450 and the individuality of species.

The P450 superfamily is expanding rapidly on many fronts. Arabidopsis genomic sequencing is producing about 2 to 3 novel P450s per week, with some clusters containing 9-14 genes. Bacterial genomes also carry surprises, such as the 20 P450s found in Mycobacterium tuberculosis and the 7 in Bacillus subtilis. The race to finish the human genome has already identified the majority of human P450s, some by expressed sequence tags only. The rapid discovery of new genes is being complemented by detailed analysis of our human genes to identify and characterize the complete set of human P450 polymorphisms and disease-causing mutations, one aspect of our "chemical individuality." Phylogenetic trees are included for plant, fungal, animal, and bacterial P450s. Emphasis is given to the higher order nomenclature of P450 clans, as a tool to see the larger picture of P450 evolution. Arabidopsis is the current record holder in P450 genes, with 186 named genes and a prediction of 350 in the total genome to be completed next year. The biosynthesis of cholesterol in bacteria is discussed in relation to CYP51 as a lanosterol 14 alpha-demethylase. This enzyme may have been the first eukaryotic P450.

Animals↗

The utility of noninvasive serologic markers in the management of early allograft rejection in liver transplantation recipients.

BACKGROUND: Early allograft rejection after orthotopic liver transplantation (OLT) currently requires a biopsy for diagnosis. Alpha-glutathione S-transferase (alpha-GST) and Pi-glutathione S-transferase (Pi-GST) are potential noninvasive markers of hepatocyte and biliary epithelial cell injury. Our aim was to determine the utility of noninvasive serologic markers in the management of early hepatic allograft rejection. METHODS: Forty-four of 52 consecutive adult patients undergoing primary OLT at the University of Florida were included in the study. All had protocol liver biopsies between days 6 and 8 after OLT. Serum alpha-GST and plasma Pi-GST were determined using a sandwich enzyme immunoassay (Biotrin International, Dublin, Ireland). All biopsy specimens were retrospectively reviewed and scored for rejection and cholestasis. RESULTS: The biopsy specimens were scored for rejection as moderate to severe in 14 patients (group 1) or none to mild in 30 patients (group 2). Group 1 had statistically higher mean levels than group 2 for alpha-GST on days 6, 7, and 9; alanine aminotransferase on days 6 and 9; aspartate aminotransferase (AST) on days 6 and 7; alkaline phosphate (AP) on days 3 through 7, 9, and 10; and gamma-glutamyl transferase on day 3. No differences between groups were seen with Pi-GST or total bilirubin. Between days 6 and 8, the following values were found more frequently in group 1 than group 2: alpha-GST level >15 ng/ml (11/14 vs. 14/30; P<0.01); AST >100 U/L (8/14 vs. 2/30; P=0.002); and AP >120 U/L (14/14 vs. 17/30). Combining AP with either alpha-GST or AST led to improved detection of rejection over any single marker alone. In the first week after the initiation of rejection treatment, alpha-GST was the only marker that accurately predicted response. CONCLUSION: Serum alpha-GST may be useful in the management of early hepatic allograft rejection. A combination of noninvasive markers may be beneficial to diagnose early hepatic allograft rejection.

Adult↗

1H-MRS evidence of neurodegeneration and excess glutamate + glutamine in ALS medulla.

OBJECTIVE: To determine whether short echo-time (TE) proton magnetic resonance spectroscopic imaging (1H-MRSI) can detect in vivo differences in signal intensities of specific metabolites in the medulla of patients with ALS compared with healthy individuals and whether these metabolites could be useful surrogate markers of disease. BACKGROUND: 1H-MRSI can detect N-acetylaspartate + N-acetylaspartylglutamate (abbreviated NAx), which is localized to neurons, and glutamate (Glu) + glutamine (Gln), abbreviated Glx, which may be important in ALS pathogenesis. The medulla is an ideal region to study ALS because of its high density of nuclei and fiber tracts that frequently undergo degeneration, even when more rostral brain regions show minimal pathology. METHODS: Ten patients with ALS and seven healthy control subjects underwent short TE 1H-MRSI on a 1.5 T clinical imaging system. Signal intensities of NAx and Glx were normalized to creatine-phosphocreatine and compared between groups. RESULTS: Compared with normal subjects, the medulla of patients with ALS had 17% lower NAx (p = 0.03) and 55% higher Glx (p = 0.02) signals. Bulbar symptoms, represented by the ALS Functional Rating Scale, correlated with Glx (r = -0.68, p = 0.03) but not NAx (r = 0.22, p = 0.53). CONCLUSION: There is in vivo 1H-MRSI evidence of neuronal degeneration or loss and excess Glu + Gln in the medulla of patients with ALS. Although this cross-sectional study cannot identify which change occurred first, the higher Glx signal in the medulla of patients with more dysarthria and dysphagia is consistent with the hypothesis of Glu excitotoxicity in ALS pathogenesis. Longitudinal 1H-MRSI studies of the medulla (and other brain regions) in more patients with ALS are required to confirm these findings and to determine whether such metabolite changes will be useful in monitoring disease progression, in clinical diagnosis, and in understanding the pathogenesis of ALS.

Adult↗

Driven polymer translocation through a narrow pore.

Motivated by experiments in which a polynucleotide is driven through a proteinaceous pore by an electric field, we study the diffusive motion of a polymer threaded through a narrow channel with which it may have strong interactions. We show that there is a range of polymer lengths in which the system is approximately translationally invariant, and we develop a coarse-grained description of this regime. From this description, general features of the distribution of times for the polymer to pass through the pore may be deduced. We also introduce a more microscopic model. This model provides a physically reasonable scenario in which, as in experiments, the polymer's speed depends sensitively on its chemical composition, and even on its orientation in the channel. Finally, we point out that the experimental distribution of times for the polymer to pass through the pore is much broader than expected from simple estimates, and speculate on why this might be.

Cell Membrane Permeability↗

Risk factors for multiple gestation in women undergoing intrauterine insemination with ovarian stimulation.

OBJECTIVE: To identify whether sperm characteristics after washing and/or ovulation induction cycle characteristics can predict the occurrence of multiple conception in patients undergoing ovarian stimulation and IUI. DESIGN: Retrospective study. SETTING: A gynecology clinic and an andrology laboratory at a tertiary care facility. PATIENT(S): One hundred patients with single pregnancies and 22 patients with multiple pregnancies. INTERVENTION(S): Patients underwent ovarian stimulation and IUI with their partner's sperm. MAIN OUTCOME MEASURE(S): Relation of patient characteristics, ovarian stimulation, and sperm characteristics after washing to the occurrence of multiple pregnancy. RESULT(S): The mean serum E2 level on the day of hCG injection was significantly higher in the multiple conception group, but the number of follicles was not. The total sperm count, total motile sperm count, and sperm motility after washing did not differ between the groups. However, couples with multiple pregnancies had sperm with a significantly higher amplitude of lateral head movement than couples with single pregnancies. A peak E2 level of >583 pg/mL on the day of hCG injection and sperm with an ALH of >4 microm after washing predicted the occurrence of multiple pregnancy. CONCLUSION(S): Sperm with an amplitude of lateral head movement of >4 microm and a peak E2 level of >583 pg/mL are significant risk factors for multiple pregnancy in patients undergoing IUI.

Adult↗

Treatment of erectile dysfunction with sildenafil citrate (Viagra) after radiation therapy for prostate cancer.

OBJECTIVES: To determine the response to sildenafil citrate (Viagra) in patients with erectile dysfunction after radiation therapy for localized prostate cancer. METHODS: Baseline and follow-up data from 21 patients presenting with erectile dysfunction after radiation treatment for clinical T1-2 prostate cancer were obtained. Two patients had undergone iodine-125 seed implantation and the remaining 19 conformal external beam irradiation. All 21 patients were considered to have erectile dysfunction as assessed by the International Index of Erectile Function (IIEF) and were prescribed sildenafil at a dosage of 50 mg, with a titration to 100 mg if needed. The mean time between the completion of radiation therapy and initiation of sildenafil was 24.6 +/- 5.8 months. The quality of the erectile function was assessed after a minimum of four doses by using the Cleveland Clinic Erectile Function (CCEF) questionnaire and the IIEF questionnaire. A positive response to sildenafil on the CCEF questionnaire was defined as an erection sufficient for vaginal penetration. The responses on the IIEF questionnaire were rated on a scale of 1 (almost never) to 5 (almost always), with 0 being no sexual activity. RESULTS: On the CCEF questionnaire, 71% (15 of 21) of patients had a positive response, with a mean duration of 12.7 +/- 2.5 minutes of intercourse, and a corresponding spousal satisfaction rate of 71%. Twelve (80%) of the 15 responders required titration to the 100-mg dosage for maximal effect. The most common side effects seen were transient flushing (19%), abnormal color vision (14%), and headaches (10%). No patient discontinued the drug because of side effects. On the IIEF questionnaire, the responses to questions 3 (frequency of penetration), 4 (maintenance of erection), 7 (satisfactory intercourse), and 15 (erection confidence) increased from mean baseline scores of 1.3, 1.1, 1.2, and 1.8 to final mean scores of 4.0, 3.9, 3.2, and 3.4, respectively (P <0.001). On the global efficacy question (ability to achieve firm erections), 71% of the patients responded positively. CONCLUSIONS: Sildenafil citrate can improve the ability to achieve and maintain an erection in most patients with erectile dysfunction after radiation therapy for prostate cancer.

Aged↗