ß2-adrenoreceptors control human skin microvascular reactivity.

Topical α1- and α2-adrenoreceptor (ADRA1 and 2) agonists are effective in alleviating permanent vasodilation and facial erythema associated with rosacea by inducing skin vasoconstriction. Although ß-adrenoreceptor (ADRB) antagonists are used off-label for rosacea, pharmacological and pharmacodynamic data pertaining to these receptors in skin micro-vessels are lacking. Objectives: To analyse the expression of different adrenergic receptors and their contribution to vasoreactivity in skin micro-vessels. Small arteries (500-800 µm) and arterioles (<200 µm) were studied in human foreskin tissue. Specifically, ADR-A1, -A2, -B1 and -B2 expression was assayed by immunofluorescence, polymerase chain reaction (PCR), and western blotting. Small skin artery reactivity was evaluated using ex vivo myography (500-800 µm) or a visible microscope perfusion system with precision-cut skin slices (<200 µm). ADRB2 was the most highly expressed receptor in small skin arteries and arterioles, followed by ADRA2. ADRA2 activation via brimonidine-induced vasoconstriction was greater in skin arterioles than in small skin arteries, and more potent than that with norepinephrine (NE). The use of prazosin (ADRA1 inhibitor) partially attenuated brimonidine-induced vasoconstriction, indicating some activation of ADRA1 by brimonidine, at least at 10-µM concentrations. Small skin arteries and arterioles, pre-treated with prazosin and stimulated with NE, exhibited ADRB2-mediated vasodilation, which was inhibited by the beta blockers, propranolol or timolol. This study shows that ADRB2 is predominantly expressed in small skin arteries and arterioles, and that ADRBs plays a functional role in vasodilation. The data presented here indicate that ADRBs can be a therapeutic target for the treatment of rosacea.

The distribution of Preputial vessels in different severity of rat congenital hypospadias model: imaging study using micro-computerized tomography.

BACKGROUND: Micro-computerized tomography (micro-CT) is considered as an innovative non-invasive and high-resolution imaging technology. The current research aims to reconstruct the distribution of preputial vessels in different severity of rat congenital hypospadias model by micro-CT, and to provide an anatomic basis for the selection of preputial vessel pedicle flaps in surgery. METHODS: Pregnant rats were exposed to finasteride from gestational day 12 to 17. Depending on the position of the urethral meatus, the pups were divided into normal, mild hypospadias and severe hypospadias groups. Six months after birth, the preputial blood vessels were observed in vascular perfusion with Microfil (a silicone-based polymer) and scanned by micro-CT. CTvox and NRecon were utilized to reconstruct 3-dimentional (3D) images. A pathological analysis of the specimen was taken in order to determine the position of Microfil. RESULTS: The normal group and the mild hypospadias group had similar preputial image characteristics. At the junction of the inner and outer prepuce, the deep layer vessels of the superficial fascia were transversely distributed and formed a vascular ring-like structure. Among the severe hypospadias group, five had sufficient blood circulation while six had insufficient blood circulation. In sufficient blood circulation type, the ring-like vessels were found at the junction of the inner and outer prepuce similar to that of the normal and mild hypospadias group. However, only a small amount of capillary supply to this area in the insufficient type. CONCLUSION: The junction of the inner and outer prepuce with abundant blood circulation was suitable to be a vascular pedicle flap. The tubularized preputial island flaps were consistent with the ring-like vessels area, and the original blood supply was retained to the greatest extent.

Role of Klotho in migration and proliferation of human dermal microvascular endothelial cells.

PURPOSE: To examine the possible role of Klotho (Kl) in human microvasculature. METHODS: The expression level of Kl in primary human dermal microvascular endothelial cells (HDMECs) and primary human dermal fibroblasts (HFb) was detected by real-time polymerase chain reaction amplification (qRT-PCR), Western blot analyses and immunohistochemistry. Migration of HDMECs and HFb was examined in monolayer wound healing "scratch assay" and Transwell assay. Proliferation of these cells was examined using Cell Proliferation BrdU incorporation assay. RESULTS: Our results have shown that downregulation of Kl abrogated HDMECs migration after 48h. On the other hand, migration of HFb significantly increased after blocking Kl. Lack of Kl decreased expression of genes involved in the activation of endothelial cells and enhanced expression of genes involved in extracellular matrix remodeling and organization of connective tissue. CONCLUSIONS: This study for the first time provides the evidence that Kl is expressed in HDMECs and HFb. Additionally, we have demonstrated that Kl is implicated in the process of angiogenesis of human dermal microvasculature.

The expression of ADAMTS13 in human microvascular endothelial cells.

ADAMTS13, as a specific von Willebrand factor (VWF)-cleaving protease, prevents microvascular thrombosis of VWF/platelet thrombi. It has been reported that human vascular endothelial cells could also synthesize and secrete ADAMTS13, and these reports were focused in human umbilical vascular endothelial cells. Considering the particularity of its huge quantity and structure of human microvascular endothelial cells (HMECs) in the body, whether ADAMTS13 is expressed in HMECs also needs to be confirmed. To investigate whether ADAMTS13 is expressed in HMECs. Real-time PCR (RT-PCR) amplification detected ADAMTS13 mRNA in HMEC-1 cell line. The expression and distribution of ADAMTS13 protein and VWF were detected by fluorescence immunoassay and western blot. We observed the expression and distribution of ADAMTS13 in HMECs. We confirmed the expression of ADAMTS13 mRNA in HMEC-1, and found that there were some partly common distributions of ADAMTS13 protein and VWF. This study provides the evidence that HMECs also express ADAMTS13. HMECs might also be a primary source for human plasma ADAMTS13. The overlap region for the distribution of ADAMTS13 and VWF suggests that ADAMTS13 might have a potential regulation role for VWF inside cells.

Unexpected Complications Following Adult Medical Male Circumcision Using the PrePex Device.

INTRODUCTION: In this study, we describe and depict unexpected sequelae of adult medical male circumcision (MMC) using the PrePex device. MATERIALS AND METHODS: The PrePex system is an elastic compression device for adult MMC. The device is well studied, has been pre-qualified by the World Health Organization (WHO), and its use is being scaled-up in African countries targeted by WHO. We conducted a PrePex implementation study in routine service delivery among 427 men in the age range of 18-49 in western Kenya. We captured penile photographs to create a record of adverse events (AEs) and to monitor healing. Several unexpected AEs ensued, including some that have not been reported in other PrePex studies. We describe and depict those unexpected complications and resulting treatments to alert circumcision providers in the relevant areas. RESULTS: We observed 5 device displacements (1.2%); 3 cases of early sloughing of foreskin tissue (0.7%) among men with long foreskins; 2 cases of a long foreskin obstructing urine flow, as it became dry and necrotic (0.5%); and 2 cases of insufficient foreskin removal caused by invagination for which surgical completion was necessary (0.5%). All of the participants healed completely by day 42 post-circumcision or shortly thereafter. CONCLUSION: The potential for these complications should be incorporated into PrePex training programs. Integration of devices into MMC programs in medically underserved areas requires the availability of prompt surgical intervention for some sequelae, particularly displacement events.

Human microvascular endothelial cells displaying reduced angiogenesis and increased uptake of lipids during in vitro culture.

Human microvascular ECs from the neonatal foreskin of two donors purchased from one distributor were used in an angiogenesis assay under the same culture conditions. Different angiogenic potency was apparent in these two batches (ECang and ECnon-ang). During the cultivation period of three weeks, ECang ran through all stages of angiogenesis starting from proliferation to migration up to the formation of three-dimensional capillary-like structures. Despite of expression of endothelial markers, ECnon-ang showed excessive intracellular storage of lipids in form of multilamellar bodies and decreased angiogenic potency in contrast to its counterpart, ECang. Results indicate that lipid metabolism differs in ECang versus ECnon-ang. This study points up that these differences are based on the different donors and presents a novel and valuable model for the study of mechanisms of atherosclerosis in endothelial cells in vitro.

Single-stage preputial skin flap urethroplasty for long-segment urethral strictures: evaluation and determinants of success.

OBJECTIVE: To determine the overall efficacy and predictors of success of the penile preputial flap in the management of complex urethral strictures >2.5 cm in length. PATIENTS AND METHODS: We performed a retrospective and prospective study of 58 patients undergoing single-stage penile preputial flap urethroplasty for complex long-segment urethral strictures, without lichen sclerosus, repaired between May 2005 and April 2012 at our institution. For obvious reasons circumcised patients were excluded from the study. Results were assessed by univariate analysis of various patient characteristics, preoperative and postoperative patient satisfaction (based on symptoms), and urethral ultrasonography, retrograde urethrography and uroflowmetry. RESULTS: The median (range) follow-up was 42 (6-90) months, the median (range) intra-operative stricture length was 48.5 (26-85) mm and the median (range) operating time was 90 (85-125) min. A total of 87.93% of patients had a satisfactory outcome, with an overall success rate of 81.03%. Diabetes mellitus (relative risk [RR] 5.21, confidence interval [CI] 2.31-64.68, P = 0.003) and smoking (RR 4.19, CI 1.54- 45.0, P = 0.01) were predictors of failure, while postinfective aetiology (RR 2.19), panurethral stricture (RR 2.73), stricture length >70 mm (RR 3.25), previous urethroplasty (RR 2.4) and severe peri-urethral fibrosis (RR 2.37) were also associated with a higher risk of failure. CONCLUSIONS: A urologist should try to gain experience of all the methods of urethroplasty as the techniques may vary according to the circumstances. Single-stage preputial skin flap urethroplasty, in experienced and expert hands, has results equivalent to all other methods of urethroplasty in complex urethral strictures. We prefer this technique in this part of the world where buccal mucosa cannot be used because of dyskeratotic changes as a result of consumption of gutkha, tobacco, pan masala, betel nut.

The correlation between preputial blood flow and microvessel density in distal hypospadias: a prospective clinical study.

OBJECTIVE: A prospective clinical study was designed to investigate the correlation between preputial blood flow (BF) and microvessel density (MVD). PATIENTS AND METHODS: A total of 44 children were included in the study. The hypospadias group consisted of 16 children undergoing distal hypospadias repair, and the control group consisted of 28 age-matched healthy children undergoing circumcision. BFs were measured using a laser Doppler flowmeter on the most distal part of the dorsal prepuces, and then the tissue samples were harvested from the same location. They were immunostained with an antibody against CD31 in order to assay MVD. The statistical analyses were carried out using Student's t test and Pearson's correlation analysis. RESULTS: The preputial MVD was found to be significantly decreased in the patients with hypospadias compared with the healthy children (33.95 ± 9.79 vs. 48.25 ± 10.08; p < 0.05), whereas there was no difference in terms of the BF (40.58 ± 16.16 vs. 33.09 ± 19.65; p > 0.05). CONCLUSIONS: We found no correlation between the preputial MVD and BF in the present study. This result suggests that reduced preputial MVD does not have any influence on BF in distal hypospadias.

Surgical technique for antegrade dissection of the preputial vascular pedicle during hypospadias repair.

OBJECTIVE: Both layers of the prepuce can be used as vascularized flaps in hypospadias repair. The aim of this communication is to describe an antegrade approach to the harvesting of the vascular pedicle. SURGICAL TECHNIQUE: The vascular pedicle is isolated at the level of the penopubic junction where it is most robust. Dissection then proceeds distally towards the prepuce fanning laterally. RESULTS: Of 306 boys presenting for hypospadias repair in 2002-2008, this approach was utilized in 235 (77%). The vascularized flap was used as 1) a classic single or double faced onlay flap in 95, 2) a vascularized layer to cover a tubularized incised plate urethroplasty in 68, 3) a tube-onlay in 39, 4) a tubularized urethroplasty in 23, 5) for ventral skin coverage alone in 7, and 6) for a planned first stage repair in 3. Age at repair averaged 12 months (range 2-160) and follow up 36 months (range 2-68). CONCLUSIONS: Antegrade dissection of the vascular pedicle is a simple, expeditious and reliable way of isolating the prepuce on its blood supply. The versatility of the resulting flaps allows the repair to be adapted to the individual anatomic conditions as opposed to one type of repair being used for all variants.

Structural study of prepuce in hypospadias--does topical treatment with testosterone produce alterations in prepuce vascularization?

PURPOSE: Androgen stimulation before hypospadias surgery has resulted in increased penile size, fewer complications and improved cosmesis, and suggests increased neovascularization. To our knowledge the real effect on neovascularization remains to be proved. We studied the histological effects of testosterone on neovascularization. MATERIALS AND METHODS: A total of 26 boys with hypospadias were randomly allocated to 2 groups before surgical correction. Group 1 did not receive any treatment and group 2 received 1% testosterone propionate ointment twice daily for 30 days before surgery. During the surgical procedure a fragment of prepuce was excised and prepared for histological evaluation. The number and volume density of blood vessels were determined by labeling for von Willebrand's factor. Blood vessel quantification as volume density was done using a video microscopy system with a superimposed cycloid arch test system. RESULTS: The groups were similar in age and hypospadias classification. Testosterone treated prepuces (group 2) had an increased absolute number of blood vessels (mean ± SD 8.5 ± 1.3 vs 4.8 ± 1.8 vessels per field) and increased blood vessel volume density (mean 50.5% ± 7.8% vs 24.8% ± 8.6% vessels per point) (each p <0.001) compared to those in untreated patients (group 1). CONCLUSIONS: The use of 1% testosterone propionate ointment before hypospadias surgery produces neovascularization in absolute numbers and in volume density.

The microvessel density of the hypospadiac prepuce in children.

OBJECTIVE: The blood supply of the hypospadiac prepuce is crucial for success in surgery. Although the vascular anatomy of the hypospadiac prepuce has been previously documented, data on microvessel density are missing. It was aimed to document the microvessel density of the normal and hypospadiac prepuce. METHODS: After ethical approval of the study, prepuces from 24 children with hypospadias undergoing surgical repair and from 9 healthy age-matched controls were stained by immunohistochemical methods using panendothelial cell antigen CD31 in order to assay their microvessel density. RESULTS: The microvessel density was significantly decreased in hypospadiac children when compared to controls (P<0.05). A gradual decrease in microvessel density was observed as the severity of the condition increased, indicating a significant negative correlation (r=-0.585; P<0.05). CONCLUSION: Our findings should be taken into account when considering preoperative treatments such as topical testosterone application or operative strategies for hypospadias using prepucial flaps, and also during the postoperative course, especially when it is complicated. Further studies are needed to clarify the role of vascularity in the pathogenesis of hypospadias and its consequences for surgical repair.

The prepuce: preservation and reconstruction.

PURPOSE OF REVIEW: To analyze the role of prepuce preservation in various disorders and discuss options available to reconstruct the prepuce. RECENT FINDINGS: The prepuce can be preserved in selected cases of penile degloving procedures, phimosis or hypospadias repair, and penile cancer resection. There is no clear evidence that debilitating and persistent preputial lymphedema develops after a prepuce-sparing penile degloving procedure. In fact, the prepuce can at times be preserved even if lymphedema develops. The prepuce can potentially be preserved in both phimosis and hypospadias repair. Penile cancer localized to the prepuce can be excised using Mohs' micrographic surgery without compromising survival. Reconstruction of the prepuce still remains a theoretical topic. There has been no study that has systematically evaluated efficacy of any reconstructive procedures. SUMMARY: The standard practice for preputial disorders remains circumcision. However, prepuce preservation is often technically feasible without compromising treatment. Preservative surgery combined with reconstruction may lead to better patient satisfaction and quality of life.