Quantitative trait loci affecting morphology traits in gilthead seabream (Sparus aurata L.).

We report a quantitative trait loci (QTL) mapping study on 18 morphometric characters in gilthead seabream based on a total of 74 informative microsatellite markers genotyped in 409 offspring coming from 10 paternal half-sib families. Statistical analysis was carried out using a linear regression approach, and various suggestive and significant morphology QTL were detected in three (9, 21 and 25) of nine linkage groups examined. Fitting body weight as a covariate reduced the significance of some QTL but revealed three new QTL in other linkage groups (LG6 and LG10). Current results combined with those obtained from previous studies underline highly significant loci affecting overall growth and morphology in S. aurata.

Genetic characterization and evaluation of anthropogenic impacts on genetic patterns in cultured and wild populations of mussels (Mytilus galloprovincialis) from Greece.

Despite the great commercial and economic importance of mussels, Mytilus galloprovincialis (Bivalvia, Mollusca) in Greece, little information is available concerning their population genetic structure. We used RAPD markers to examine genetic differentiation and potential impact of aquaculture practices and other anthropogenic activities on the genetic structure of two cultivated and eight wild mussel populations collected from one Turkish and nine Greek coast sites. Five random decamer primers were chosen, among 34 tested, for the analysis of 433 individuals. Eighty-eight bands (genetic loci) were scored, all of which were polymorphic. No indication of reduced genetic variability was observed in the cultured populations. In contrast, a loss in genetic diversity was observed in populations from two localities (Canakkale and Kalochori) that are heavily polluted by chemical contaminants. FST analyses and exact tests revealed significant heterogeneity among M. galloprovincialis population samples, although their genetic divergence seemed to be independent of geographic distances. Anthropogenic activities, i.e., marine pollution and transplantation of mussels, appear to have played an important role in shaping patterns of genetic diversity and differentiation among Greek M. galloprovincialis populations.

Quantitative trait loci for body growth and sex determination in the hermaphrodite teleost fish Sparus aurata L.

Gilthead sea bream (Sparus aurata L.) is an important marine fish in Mediterranean aquaculture. Sex determination by age and/or body weight is a critical life-history trait, the genetic basis for which is largely unknown in this sequential hermaphrodite species. Herein, we performed a partial genome scan to map quantitative trait loci (QTL) affecting body weight and sex using 74 informative microsatellite markers from 10 paternal half-sib families to construct nine linkage groups (LG). In total, four growth-related QTL (two chromosome-wide and two genome-wide) and six QTL related to sex determination (three pairs in three different LGs) were detected (two chromosome-wide and one genome-wide). The proportion of phenotypic variation explained by the body-weight QTL ranged from 9.3% to 17.2%, showing their potential for use in marker-assisted selection. The results obtained offer solid ground to investigate the structure and function of the genomic regions involved in the mechanisms of sex reversal.

Genetic divergence among native trout Salmo trutta populations from southern Balkans based on mitochondrial DNA and microsatellite variation.

The genetic structure and the phylogenetic relationships among five Balkan populations of trout Salmo trutta that have been classified earlier into five different taxa were studied, using microsatellite and mitochondrial DNA (mtDNA) analyses. The pattern of population differentiation observed at microsatellites differed to that depicted by mtDNA variation, yet both methods indicated a very strong partitioning of the genetic variation among sampling locations. Results thus suggest that conservation strategies should be directed towards preserving the genetic integrity and uniqueness of each population.

Genetic diversity among Balkan trout populations based on RAPD analysis.

Random amplified polymorphic DNA (RAPD) markers were used to estimate the population structure and phylogenetic relationships among samples of the Salmo trutta complex that inhabit the Balkan Peninsula. Five random oligodecamers were selected to amplify DNA from 140 fish from seven populations. Using these primers, 55 discernible DNA fragments were generated, of which 50 (90.91%) were polymorphic. The statistical results indicated that there was low genetic diversity within populations (with an average percentage of polymorphic bands (P) of 11.69% and a Nei's genetic diversity index (h) of 0.035), but at the same time high genetic differentiation among populations (F(ST) = 0.89). The distribution of genetic diversity among Balkan trout may result from their evolutionary history and reflects genetic drift coupled with bottleneck phenomena. Overall, RAPDs proved valuable tools for quick and reliable stock discrimination and provided information that might be useful regarding conservation and management of trout.

The use of botulinum neurotoxin type A (BoNTA) in urology.

The use of Botulinum neurotoxin type A (BoNT/A) in the lower urinary tract was pioneered as early as 20 years ago with injections into the urethral sphincter reducing bladder voiding pressures, urethral pressures, and post-void residual urine. Over the past 9 years, the use of BoNT/A has revolutionised the treatment of intractable symptoms associated with the neurogenic or idiopathic overactive bladder, both in adults and children. The duration of clinical improvement is 6-11 months, is accompanied by significant amelioration of patients' quality of life and repeat bladder treatments appear to have sustained effects. Despite evidence for an effect on the afferent pathways, its mode of action in the human bladder remains largely unknown. The use of BoNT/A has also expanded into the painful bladder syndrome and in benign prostatic diseases, with promising preliminary results. This review aims to provide an insight of the use of BoNT/A in the lower urinary tract, addressing issues such as treatment outcomes and safety, mechanisms of action and potential for future research.

Decreased sensory receptors P2X3 and TRPV1 in suburothelial nerve fibers following intradetrusor injections of botulinum toxin for human detrusor overactivity.

PURPOSE: Botulinum neurotoxin type A (BoNT/A) is effective in the treatment of intractable detrusor overactivity (DO). In addition to its known inhibitory effect on presynaptic release of acetylcholine by motor terminals, there is increasing evidence that BoNT/A may affect sensory fibers. We investigated a possible effect of BoNT/A on human bladder afferent mechanisms by studying the sensory receptors P2X3 and TRPV1 in biopsies from patients with neurogenic or idiopathic DO. MATERIALS AND METHODS: A total of 38 patients (22 with neurogenic DO, 16 with idiopathic DO) with intractable DO were treated with intradetrusor BoNT/A, and bladder biopsies were taken at 4 and 16 weeks. Urodynamics and voiding diary were also recorded. Specimens were studied immunohistochemically for P2X3, TRPV1 and the pan-neuronal marker PGP9.5, in comparison with controls. RESULTS: P2X3-immunoreactive and TRPV1-immunoreactive (-IR) fibers were decreased at 4 weeks after BoNT/A, and more significantly at 16 weeks (paired t test p=0.0004 and p=0.0008, respectively), when significant improvements were observed in clinical and urodynamic parameters. P2X3-IR fiber decrease was significantly correlated with reduction of urgency episodes at 4 and 16 weeks (p=0.0013 at 4 weeks and p=0.02 at 16 weeks), but not maximum cystometric capacity or detrusor pressures. TRPV1-IR fiber decrease showed a similar trend. PGP9.5-IR suburothelial fibers remained unchanged after treatment at both followups (p=0.85 and p=0.21 at 4 and 16 weeks, respectively). Urothelial cell P2X3-IR and TRPV1-IR also appeared unchanged. CONCLUSIONS: Decreased levels of sensory receptors P2X3 and/or TRPV1 may contribute to the clinical effect of BoNT/A in detrusor overactivity.

Parallel changes in bladder suburothelial vanilloid receptor TRPV1 and pan-neuronal marker PGP9.5 immunoreactivity in patients with neurogenic detrusor overactivity after intravesical resiniferatoxin treatment.

OBJECTIVE: To compare PGP9.5 and transient receptor potential vanilloid receptor (TRPV1) suburothelial immunoreactivity between controls and patients with spinal neurogenic detrusor overactivity (NDO) before and after treatment with intravesical resiniferatoxin, as suburothelial PGP9.5-staining nerve fibres decrease in patients with spinal NDO who respond to intravesical capsaicin, and TRPV1 is present on these suburothelial nerve fibres in normal and overactive human urinary bladder. PATIENTS AND METHODS: Patients with refractory NDO were enrolled in a prospective, randomized, parallel-group, double-blind, placebo-controlled trial using escalating doses of resiniferatoxin to a maximum of 1 micro mol/L. Flexible cystoscopic bladder biopsies obtained at baseline, 4 weeks after each instillation and at the time of maximum clinical response were compared with biopsies taken from control subjects. Frozen sections were incubated with rabbit antibodies to TRPV1 and PGP9.5, and assessed using standard immunohistochemical methods. PGP9.5 nerve density was analysed using a nerve-counting graticule by an observer unaware of sample origin. Another two independent observers unaware of each other's results used a random grading scale to evaluate TRPV1 nerve fibre density and intensity. The immunohistochemistry results were compared with histology findings (haematoxylin-eosin), and the Mann-Whitney test used to assess any differences (P < 0.05 significant) and the Pearson test for correlation. RESULTS: There were eight controls and 20 patients with spinal NDO, 14 (five clinical responders and nine not) who received the maximum dose of resiniferatoxin. There were more PGP9.5 and TRPV1 nerve fibres in patients with NDO than in controls (P = 0.007 and 0.002, respectively). Immunoreactivity before resiniferatoxin was similar in both groups for both PGP9.5 and TRPV1. In responders there were fewer PGP9.5 and TRPV1-positive fibres after treatment (P = 0.008 for each) but no change in those not responding. Changes after treatment for TRPV1 correlated well with those for PGP9.5 (r = 0.88, P < 0.001). CONCLUSIONS: The decrease of PGP9.5 and TRPV1 immunoreactive nerve fibres in responders to resiniferatoxin (to levels in control tissues) suggests that the increased numbers of nerve fibres in patients with NDO are mainly of sensory origin and express TRPV1. As baseline nerve fibre values were similar in responders and nonresponders, an additional factor may account for the difference in treatment outcome.

Endothelial nitric oxide synthase expression in neurogenic urinary bladders treated with intravesical resiniferatoxin.

OBJECTIVE: To investigate endothelial nitric oxide synthase (eNOS) immunoreactivity in bladder biopsies from patients with neurogenic detrusor overactivity (NDO) before and after treatment with intravesical resiniferatoxin, and compare this with control material; the distribution of two other vascular markers, von Willebrand Factor (vWF) and the vascular endothelial growth factor (VEGF), was also studied. PATIENTS AND METHODS: Flexible cystoscopic bladder biopsies from eight controls investigated for asymptomatic microhaematuria and 19 patients with refractory spinal NDO enrolled in a clinical trial of intravesical treatment with escalating doses of resiniferatoxin were immunostained with polyclonal rabbit antibodies for eNOS, vWF and VEGF. Fewer baseline NDO specimens (eight) were available for vWF and VEGF staining. Computerized image analysis was used to quantify immunoreactivity, and the Mann-Whitney test for statistical analysis. RESULTS: eNOS immunoreactivity was found in the suburothelium and less often in the urothelium, with a distribution indicating a location in small blood vessels at the urothelium-suburothelium junction. Immunostaining for vWF showed a similar location. There was a trend to higher eNOS values before treatment in those responding than in those not responding to resiniferatoxin (P = 0.059), and a significant reduction in eNOS immunoreactivity after successful treatment (P = 0.016). VEGF staining was weaker but there was a significant increase in pretreatment biopsies of responders to resiniferatoxin (P = 0.048). Clinical and histopathology features were similar in both groups. CONCLUSIONS: The trend for higher eNOS expression in patients with NDO who responded to resiniferatoxin suggests that increased vasculature or vasodilatation in the suburothelium may be necessary for successful intravesical treatment. Further studies with more patients are required to confirm this relationship and to examine the mechanisms underlying changes in vasculature with levels of bladder overactivity.

Fetal tachycardia: is digitalis still the first-line therapy?

Medical treatment of fetal tachycardias has substantially improved neonatal outcome over the past years. Digitalis has been often used as first-line therapy in these cases, and more recently the use of several newer agents have been reported. We present four cases of fetal tachycardia with a favorable neonatal outcome after successful treatment with digitalis. Rapid transplacental digitalization appears to be an effective and reliable treatment option for fetal tachycardia, particularly in non-hydropic fetuses. In hydropic fetuses, however, digitalis alone appears to be less effective and administration of a second drug is usually needed.

Diffractive properties of volume phase gratings in photorefractive sillenite crystals of arbitrary cut under the influence of an external electric field.

We study the influence of bias dc electric field on the optical properties of volume phase gratings formed in optically active photorefractive sillenite crystals. By considering a general case where the external electric bias direction, the grating vector orientation, the light propagation direction (crystal cut), and state of polarization are arbitrary, we deduce analytical expressions for the diffraction efficiency and the polarization state of the diffracted beam. The influence of the inverse piezoelectric effect is taken into account both in the uniform and the spatially varying part of the impermeability tensor, as well as into the calculation of the effective static permittivity. A theoretical comparative study of the dynamic behavior of the diffraction efficiency as a function of the physical parameters that affect the diffraction process (crystal cut, electric bias, input polarization, and grating orientation) along with experimental verification is provided. The general analytical solution provides means of exploitation of the capabilities of sillenite crystals in several applications.

Protective role of the glans penis during coitus.

To examine the hypothesis that the glans penis acts protectively, absorbing forces, during coitus. Five potent patients (mean age 46.8+/-9.7 y), who had indication for surgical excision of the glans for penile carcinoma were included in the present study. Intraoperatively, intracavernosal pressure (ICP) was adjusted by saline infusion and maintained by a pressure feedback infusion pump to a pressure value of 70 mmHg. Using a dynamometer, an external compressive force of 0.5 kg was applied at the glans penis and the changes in ICP were monitored. Measurements were repeated after surgical excision of the glans. Significant ICP changes were noticed in all patients after excision of the glans. Mean preoperative ICP was 161+/-11.5 mmHg, while after glansectomy it reached 206.6+/-13 mmHg. DeltaICP was 45.8+/-10.57 mmHg. Two of the patients' partners reported pain during intercourse postoperatively, possibly due to the impact of the force applied by the rigid corpora cavernosa on the anterior vaginal wall without any absorption by the glans. The glans penis restricts the increase in ICP during sexual intercourse, playing a protective role for both the corpora cavernosa and the female genitalia.

Erectile and urinary dysfunction may be the presenting features in patients with multiple system atrophy: a retrospective study.

Multiple system atrophy (MSA) is a progressive neurodegenerative disease characterized by parkinsonism and cerebellar, autonomic, urinary, and/or pyramidal dysfunction. Urinary and erectile dysfunction (ED) symptoms are prominent early features in men with MSA. Autonomic failure, considered until recently to be the cause of ED in these men, is commonly expressed through symptoms of orthostatic hypotension (OH). The aim of this retrospective study is to examine the chronological relationship between the development of urogenital symptoms and those of OH in patients diagnosed with MSA and discuss its significance in the aetiology of ED in these patients. A total of 71 male patients, referred to a Uro-Neurology department with a diagnosis of 'probable MSA', were reviewed in terms of 'autonomic' symptoms only--OH and lower urinary tract symptoms, accompanied by ED--present at the time of their referral. Laboratory investigations including anal sphincter EMG and/or autonomic function tests (AFTs) were performed in 75 and 90% of the patients, respectively. At presentation, urinary complaints were recorded in 96% of patients and ED in all patients that this was inquired about. The onset of ED had preceded the onset of bladder symptoms in 58% and the onset of OH symptoms in 91% of these men. Bladder symptoms also preceded symptoms of OH in 76% of patients. Sphincter EMG was abnormal in 91% and AFTs in 77% of the patients tested. Almost all patients with abnormal EMG had troublesome urinary symptoms. AFTs showed similar sensitivity relating to symptoms. At presentation, urogenital symptoms are common in patients with probable MSA and are often not accompanied by symptoms of OH. The earlier occurrence of ED in men with MSA suggests a lack of a causal relationship to hypotension. The notion that MSA possibly affects the dopaminergic mechanism of erectile function is discussed.

Normal hemodynamic parameters do not always predict the presence of a rigid erection: a quantitative assessment of functional erectile impairment.

The purpose was to assess objectively and quantitatively the hemodynamic status and the degree of functional erectile impairment in a group of impotent patients. A clinical study was designed, incorporating pharmacocavernosometry (to evaluate arterial and veno-occlusive function) with axial buckling forces and penile geometry measurements in a group of impotent patients. The pressure gradient between the intracavernosal pressure associated with the presence of penile axial rigidity and the equilibrium intracavernosal pressure was calculated (axial rigidity gradient, ARG); such methodology allowed a quantitative characterization of functional impairment, as ARG expresses the intracavernosal pressure increase necessary to achieve axial rigidity and therefore potency. Penile geometry characteristics were also expressed by calculating the penile aspect ratio (diameter/length, D/L). In 83 consecutive patients tested (mean age 42.89+/-9.96), rigidity occurred at intracavernosal pressures between 50 and 100 mm Hg. A conversely proportional relation was noticed between penile aspect ratio values and the intracavernosal pressure associated with rigidity values, clearly demonstrating the important functional role of penile geometry. ARG demonstrated a wide range of values (3-69 mm Hg), reflective of the severity of the erectile dysfunction on each patient. Half (50.6%) of the patients had ARG values < or =20 mm Hg, indicative of minimal and minimal-to-moderate erectile impairment, while 20.48% had ARG between 21-30 and 28.92% >30 mm Hg, indicative of moderate and severe erectile dysfunction (ED) respectively. In all, 6% of the study group, all of them with primary ED, ARG <20 mm Hg had normal hemodynamics, but low penile aspect ratio values indicating that penile geometry may be the cause of insufficient rigidity. Hemodynamic integrity is the most critical, but not the only determinant of penile rigidity, as erectile impairment may be noticed in patients with normal arterial inflow and corporal veno-occlusive function. In such cases, unfavorable penile geometry should be considered as the possible etiological factor of impotence.

Phylogenetic relationships among four species of Mullidae (Perciformes) inferred from DNA sequences of mitochondrial cytochrome b and 16S rRNA genes.

DNA sequence comparisons of two mitochondrial DNA genes were used to infer phylogenetic relationships among four species of mullids. Approximately 238bp of the mitochondrial 16S ribosomal RNA (rRNA) and 261bp of the cytochrome b (cytb) genes were sequenced from representatives of three mullid genera (Mullus, Upeneus, Pseudopeneus), present in the Mediterranean Sea. Trees were constructed using three methods: maximum likelihood (ML), neighbor joining (NJ) and parsimony (MP). The results of the analyses of these data together with published data of the same mtDNA segments of two other perciform species (Sparus aurata, Perca fluviatilis), support the previous taxonomic classification of the three genera examined, as well as the classification of the two red mullet species in the same genus.

Glansectomy: an alternative surgical treatment for Buschke-Löwenstein tumors of the penis.

OBJECTIVES: To present the surgical excision of the glans penis (glansectomy) as an alternative surgical treatment to penectomy. Buschke-Löwenstein tumors of the penis include the entities described in published reports as verrucous carcinoma and giant condyloma acuminatum of the penis. Both types are well-differentiated tumors, typically confined to the glans penis, with distinctly rare metastatic activity. METHODS: The study included 7 patients, 40 to 63 years of age, with exophytic, papillary lesions involving the glans penis. Biopsy led to the diagnosis of verrucous carcinoma in 4 patients and giant condyloma acuminatum in 3 patients. All patients reported normal erectile function. Because of the low malignant potential of the tumor and its confinement to the glans penis, a simple glansectomy was performed in all patients to preserve the maximal penile length and functional integrity of the corpora cavernosa. RESULTS: The postoperative course was uncomplicated. With 18 to 65 months of follow-up, all patients were disease free. One patient required more aggressive treatment because of local recurrence of the tumor. All patients returned to normal sexual activity 1 month postoperatively. The only change during sexual activity, noted by two of the patients' partners, was vaginal pain, possibly due to the absence of the glans. CONCLUSIONS: Glansectomy may be considered the treatment of choice in patients with Buschke-Löwenstein tumors of the penis, with more radical techniques reserved for second-line treatment.

Effects of oral phentolamine, taken before sleep, on nocturnal erectile activity: a double-blind, placebo-controlled, crossover study.

The objective of this study was to determine the effects of oral phentolamine, administered before sleep, on nocturnal penile erectile activity of men with mild to moderate erectile dysfunction (ED). We studied five patients with mild to moderate ED (mean age 34.8 +/- 8.13 and mean duration of ED 31.8 +/- 23.5 months), in a double-blind, placebo-controlled, crossover study. All patients received oral phentolamine (Vasomax) at a dose of 40 mg and placebo for three consecutive nights respectively and were submitted to nocturnal penile tumescence and rigidity monitoring (NPTR) with the Rigiscan device. NPTR parameters of the two 3-night recordings were evaluated and compared. Administration of oral phentolamine before sleep was associated with a statistically significant increase in the number of erectile events with rigidity > or = 60% lasting > or = 10 min (P = 0.02), as well as the rigidity activity units (RAU) value per hour sleep, both at the base (P = 0.023) and the tip of the penis (P = 0.019). The number of events as measured by Rigiscan software (20% change in circumference), as well as tumescence activity units (TAU)/h values did not show any statistical difference. No adverse effects were recorded. It is concluded that oral phentolamine administered before sleep enhanced NPTR parameters associated with the quality of the erectile events. Such results provide a pathway for the development of a prevention strategy for ED. Future studies will elucidate whether vasoactive agents taken on a regular basis before sleep, can prevent ED in men at risk, protecting also minimally and moderately impotent patients to become moderately and severely impotent respectively.

RFLP analysis of mitochondrial DNA to evaluate genetic variation in striped red mullet (Mullus surmuletus L.) and red mullet (Mullus barbatus L.) populations.

The genetic differentiation of striped red mullet (Mullus surmuletus) and red mullet (Mullus barbatus) was investigated in 6 Mediterranean populations of each species by means of restriction fragment length polymorphism analysis of mitochondrial DNA. Three segments amplified by polymerase chain reaction (control region, COI, and 12S-16S ribosomal RNA) were digested with 20 restriction endonucleases, revealing 71 haplotypes for M. surmuletus and 30 for M. barbatus. For the two species nucleotide diversity was equally distributed within and among populations, leading to N(ST) values of 0.545 and 0.500 for M. surmuletus and M. barbatus, respectively. However, intrapopulation and interpopulation genetic structuring appeared to be much higher for M. surmuletus than for M. barbatus (1.88% vs. 0.46% of mean intrapopulation nucleotide diversity; 1.94% vs. 0.47% of mean interpopulation nucleotide diversity; 0.055% vs. 0.002% of net interpopulation divergence). Furthermore, 81.69% of the haplotypes observed for M. surmuletus were unique, whereas 70.29% of M. barbatus individuals were grouped in 3 common haplotypes. Given that fishing pressure and population sizes are similar for both species, this differentiation could be attributed to differences in biological parameters and life histories between the two species, coupled with oceanographic conditions prevailing in the studied area.

Mitochondrial DNA sequence variation in Greeks.

Mitochondrial DNA (mtDNA) control region sequences were determined in 54 unrelated Greeks, coming from different regions in Greece, for both segments HVR-I and HVR-II. Fifty-two different mtDNA haplotypes were revealed, one of which was shared by three individuals. A very low heterogeneity was found among Greek regions. No one cluster of lineages was specific to individuals coming from a certain region. The average pairwise difference distribution showed a value of 7.599. The data were compared with that for other European or neighbor populations (British, French, Germans, Tuscans, Bulgarians, and Turks). The genetic trees that were constructed revealed homogeneity between Europeans. Median networks revealed that most of the Greek mtDNA haplotypes are clustered to the five known haplogroups and that a number of haplotypes are shared among Greeks and other European and Near Eastern populations.

Sildenafil versus intracavernous injection therapy: efficacy and preference in patients on intracavernous injection for more than 1 year.

PURPOSE: To our knowledge comparative data on the effectiveness of and patient preference for intracavernous injection therapy and sildenafil are still not available. We evaluated the efficacy of sildenafil as well as patient preference in a group of impotent men on intracavernous injection for more than a year. MATERIALS AND METHODS: Patients on intracavernous injection therapy for more than a year without neurological disease and/or a contraindication to sildenafil treatment were recruited for study. In phase 1 we determined the efficacy of 50 and 100 mg. sildenafil citrate at home. In phase 2 responders to sildenafil were asked to use the preferred dose orally for a month and choose intracavernous injection or sildenafil. In phase 3 patients were asked to continue either treatment for 3 more months. Patient preferences were reported at the end of phases 2 and 3. RESULTS: Of the 180 men recruited 155 with a mean age of 56.4 +/- 12.6 years on intracavernous injection for a mean of 26 +/- 9 months accepted and were included in our series. Overall 116 men (74.8%) responded to sildenafil during study phase 1. After 1 month of treatment 71 responders (61.2%) preferred to continue with the oral drug, 31 (26.7%) returned to intracavernous injection and 14 (12.1%) used each drug alternately. Three months later 74 of the 116 responders (63.8%) preferred oral treatment and 38 (32.8%) chose intracavernous injection, while 4 (3. 4%) continued to use each treatment alternately. CONCLUSIONS: Sildenafil is highly effective in intracavernous injection responders, although a certain group prefer to continue intracavernous injection. While sildenafil should be considered first line treatment, men with erectile dysfunction should be aware of all treatment options available because nonresponders to sildenafil may respond to intracavernous injection.