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INTRODUCTION AND OBJECTIVE:The most common methods of bulbar urethral stricture surgery are resection and primary anastomosis or augmentation with onlay buccal mucosal graft. The effects on sexual ...

The aim of this study was to assess whether sclerosis in histology following bulbar urethroplasty is a predictive factor for failure of surgery.Resected stricture specimens from 45 patients undergoing open urethroplasty with excision and anastomosis were collected prospectively during 2011-2014. Histopathological characteristics, including fibrosis (grade I-III), inflammation and sclerosis, were evaluated using different routine staining. These specimens were compared to normal urethral resection specimens from patients undergoing sex-correction surgery. The uropathologist who conducted the analyses was blinded to the study design.The outcomes of the histological classifications were as follows: 19 patients had grade I fibrosis, of whom three had failures; 13 patients had grade II fibrosis, without any failures; and the most severe fibrosis, grade III, including sclerosis, was found in 13 patients (11 with sclerosis), with failure in eight. Sclerosis was a significant risk factor for restricture when comparing patients with sclerosis and those without sclerosis, and likewise when adjusting for age, inflammation and stricture length.Histological findings of sclerosis in the resected urethral stricture specimen indicate a significantly higher risk for restricture after urethroplasty surgery.

Even though more than 30 years have passed since the eradication of smallpox, high titers of smallpox-specific antibodies are still detected in the blood of subjects vaccinated in childhood. In fact, smallpox-specific antibody levels are maintained in serum for more than 70 years. The generation of life-long immunity against infectious diseases such as smallpox and measles has been thoroughly documented. Although the mechanisms behind high persisting antibody titers in the absence of the causative agent are still unclear, long lived plasma cells (LLPCs) play an important role. Most of the current knowledge on LLPCs is based on experiments performed in mouse models, although the amount of data derived from human studies is increasing. As the results from mouse models are often directly extrapolated to humans, it is important to keep in mind that there are differences. These are not only the obvious such as the life span but there are also anatomical differences, for instance the adiposity of the bone marrow (BM) where LLPCs reside. Whether these differences have an effect on the function of the immune system, and in particular on LLPCs, are still unknown. In this review, we will briefly discuss current knowledge of LLPCs, comparing mice and humans.

The aim of this study was to evaluate outcomes and possible risk factors for failure of open urethroplasty due to penile urethral strictures.A retrospective chart review was undertaken of 90 patients with penile stricture undergoing 109 open urethroplasties between 2000 and 2011. In 80 urethroplasties, a one-stage procedure was performed: 68 of these had a pediculated penile skin flap, nine had a free buccal mucosal graft and three had a free skin graft. A two-stage procedure using buccal mucosa was performed in 29 urethroplasties. Failure was defined as when further urethral instrumentation was needed.The mean age in the one-stage and two-stage groups were 50 and 54 years, respectively. The success rates in the corresponding groups were 65% and 72%, with follow-up times of 63 and 40 months, respectively. Multivariable analyses disclosed body mass index (BMI) and previous urethral surgery to be significant risk factors for failure in the one-stage group. Failure over time significantly decreased during the study period.Both one- and two-stage penile urethroplasty demonstrated success rates in line with previous reports. Limited experience, high BMI and previous urethral surgery appear to be associated with less favourable outcome.

Urethroplasty is a procedure that has a high success rate. However, there exists a small subgroup of patients who require multiple procedures to achieve an acceptable result. This study analyses the outcomes of a series of patients with failed urethroplasty.This is a retrospective review of 82 failures out of 407 patients who underwent urethroplasty due to urethral stricture during the period 1999-2013. Failure was defined as the need for an additional surgical procedure. Of the failures, 26 patients had penile strictures and 56 had bulbar strictures. Meatal strictures were not included.The redo procedures included one or multiple direct vision internal urethrotomies, dilatations or new urethroplasties, all with a long follow-up time. The patients underwent one to seven redo surgeries (mean 2.4 procedures per patient). In the present series of patients, endourological procedures cured 34% (28/82) of the patients. Ten patients underwent multiple redo urethroplasties until a satisfactory outcome was achieved; the penile strictures were the most difficult to cure. In patients with bulbar strictures, excision with anastomosis and substitution urethroplasty were equally successful. Nevertheless, 18 patients were defined as treatment failures. Of these patients, nine ended up with clean intermittent self-dilatation as a final solution, five had perineal urethrostomy and four are awaiting a new reintervention. Complicated cases need centralized professional care.Despite the possibility of needing multiple reinterventions, the majority of patients undergoing urethroplasty have a good chance of successful treatment.

Open urethroplasty is the preferred treatment for recurrent bulbar urethral stricture. However, there are still some controversies regarding the optimal technique and the consequences of transecting the urethra in terms of sexual dysfunction, such as erectile dysfunction, penile shortening, impaired glans filling, decreased glans sensibility and ejaculatory function. We performed a retrospective analysis with long-term followup of anastomotic and substitution onlay urethroplasty in bulbar strictures with an emphasis on postoperative sexual function.A total of 169 patients with bulbar stricture were treated with urethroplasty via the onlay technique (75) or resection followed by end-to-end anastomosis (94) during 1999 to 2009. Mean followup in the transection and onlay groups was 41 and 69 months, respectively (range 12 to 132). All patients were asked verbally about sexual function during followup. Failure was defined as the need for new surgical intervention.Erectile dysfunction developed in 1 patient (1%) per group. In the transection group 5 patients (5%), including 4 with longer and more distal strictures, had penile shortening/downward angulation. However, this did not interfere with sexual ability during intercourse. No patient reported impaired glans or ejaculatory function. The success rate in the transection and onlay groups was 91% and 71%, respectively.Transection with resection and end-to-end anastomosis is a good method for bulbar stricture with a low rate of sexual dysfunction and a high success rate postoperatively. To avoid penile angulation/shortening, it might be wise to use the onlay technique for longer and distal strictures.

Multi-Processor Systems on Chip (MPSoC) run multiple independent applications, often developed by different parties. The applications share the hardware resources, e.g. processors, memories and interconnect. The sharing typically causes interference between the applications, which severely complicates system integration and verification. Even if the applications are verified in isolation, the system designer must verify the combined behaviour, leading to an explosion in design complexity. Composable MPSoCs have no interference between applications, thus allowing independent design and verification. For an MPSoC to be composable, all the hardware resources must offer composability. A particularly challenging resource is the processors, often purchased as off-the-shelf intellectual property. In this work we present the design and implementation of CompOSe, a light-weight (only 1500 lines of code) composable operating system for MPSoCs. CompOSe uses fixed-size time slices, coupled with a composable scheduler, to enable composable processor sharing. Using instances of ARM7, ARM11 and the Xilinx MicroBlaze we experimentally demonstrate the ability to provide temporal composability, even in the presence of dynamic application behaviour and multiple use cases. We do so using a diverse set of processor architectures, without requiring any hardware modifications. We also show how CompOSe allows slack to be distributed within and between applications through a novel two-level scheduler and slack-distribution system.