Application of self-expandable metal stents for ureteroileal anastomotic strictures: long-term results

PURPOSE: We report our long-term experience with the management of benign ureteroileal anastomotic strictures using self-expandable metal stents. MATERIALS AND METHODS: A total of 16 male and 2 female patients with a mean+/-SD age of 72+/-7 years (range 66 to 78) with benign fibrotic strictures at the site of ureteroileal anastomosis underwent implantation of self-expandable metal stents with a nominal diameter of 6 to 8 mm. A total of 24 ureteroileal conduits were treated. The external nephrostomy tubes were removed after fluoroscopic validation of ureteral patency. Patients were followed with blood biochemistry, ultrasonography, urography and/or virtual endoscopy. Retrograde external-internal catheter insertion through the cutaneous stoma was performed in cases of recalcitrant stricture. RESULTS: The technical success rate of ureteroileal stricture crossing and stenting was 100% (24 of 24 cases). Mean followup was 21 months (range 7 to 50). The clinical success rate during the immediate post-stenting period was 70.8% (17 of 24 cases). The 1 and 4-year primary patency rates were 37.8% and 22.7%, respectively. Secondary interventions included repeat balloon dilation in 15 ureters, of which 8 also underwent subsequent coaxial stent placement. The 1 and 4-year secondary patency rates were 64.8% and 56.7%, respectively. Except in 2 patients who died external-internal Double-J catheters continued to be inserted retrograde in 6 ureteroileal conduits. They are periodically exchanged to prevent mucous inspissation and stent encrustation. CONCLUSIONS: Metal stents served as the definitive treatment for stricture in more than half of the cases, whereas in the remainder the stents allowed the uncomplicated and regular exchange of Double-J catheters in retrograde fashion. This combined, less invasive treatment for ureteroileal anastomotic strictures may help patients avoid surgical revision and preserve quality of life.     

Endothelial nitric oxide synthase uncoupling impairs endothelial progenitor cell mobilization and function in diabetes

Uncoupling of the endothelial nitric oxide synthase (eNOS) resulting in superoxide anion (O(2)(-)) formation instead of nitric oxide (NO) causes diabetic endothelial dysfunction. eNOS regulates mobilization and function of endothelial progenitor cells (EPCs), key regulators of vascular repair. We postulate a role of eNOS uncoupling for reduced number and function of EPC in diabetes. EPC levels in diabetic patients were significantly reduced compared with those of control subjects. EPCs from diabetic patients produced excessive O(2)(-) and showed impaired migratory capacity compared with nondiabetic control subjects. NOS inhibition with N(G)-nitro-l-arginine attenuated O(2)(-) production and normalized functional capacity of EPCs from diabetic patients. Glucose-mediated EPC dysfunction was protein kinase C dependent, associated with reduced intracellular BH(4) (tetrahydrobiopterin) concentrations, and reversible after exogenous BH(4) treatment. Activation of NADPH oxidases played an additional but minor role in glucose-mediated EPC dysfunction. In rats with streptozotocin-induced diabetes, circulating EPCs were reduced to 39 +/- 5% of controls and associated with uncoupled eNOS in bone marrow. Our results identify uncoupling of eNOS in diabetic bone marrow, glucose-treated EPCs, and EPCs from diabetic patients resulting in eNOS-mediated O(2)(-) production. Subsequent reduction of EPC levels and impairment of EPC function likely contributes to the pathogenesis of vascular disease in diabetes.     

Transverse bronchoplasty of the membranous wall after resection of an endobronchial hamartoma

Lung hamartomas are rare benign tumors of the bronchi. Their management consists of bronchoscopic excision or removal through a thoracotomy and bronchotomy whenever there is a large tumor totally obstructing the bronchial lumen. As a lung-sparing procedure is usually the aim, various bronchoplastic techniques have been described, providing a functional lumen of the repaired bronchus. We describe a simple technique that can be safely undertaken to preserve a satisfactory diameter of the bronchus or trachea and prevent a stenosis at the site of repair.     

Intraluminal Intestinal Administration of Oxygenated Perfluorocarbon Improves Acid–Base and Cardiopulmonary Parameters After Acute Mesenteric Ischemia. An Experimental Study in Rabbits

Purpose The aim of this study was to evaluate the effects of the intraluminal intestinal administration of oxygenated perfluorocarbon, during experimental acute intestinal ischemia, on the acid–base blood status and the cardiopulmonary parameters. Methods Thirty-six rabbits were separated into three groups: (a) Control group (ischemia alone), (b) PFC-O₂ group (ischemia plus infusion of oxygenated F-Decalin in intraluminal intestinal administration), and (c) PFC group (ischemia plus infusion of nonoxygenated F-Decalin in intraluminal intestinal administration). An equal number of the animals was then subjected to 8 h of intestinal ischemia by ligation of the superior mesenteric artery (subgroups 1), the mesenteric vein (subgroups 2) or both vessels (subgroups 3). At 0, 2, 4, 6, and 8 h arterial blood samples were taken for acid–base status tests and the vital signs (heart and respiratory rate, pressure of inferior vena cava, and systolic arterial pressure) were noted. The statistical analysis was performed by the nonparametric Kruskal–Wallis test. Results There were no significant differences in any of the studied parameters (pH, base excess, respiratory gases, pressure of inferior vena cava, systolic arterial pressure, heart and respiratory rate) between animals of the same group and subgroup. In addition, the differences among Control and PFC groups and their equal subgroups were not significant. On the other hand, the measurements of the PFC-O₂ animals showed significant differences at 4, 6, and 8 h of ischemia (P < 0.05) in comparison with those from the Control and PFC groups. Conclusion We conclude that the intraluminal intestinal administration of oxygenated perfluorocarbons may thus be a useful adjunctive therapy in the treatment of patients with acute mesenteric ischemia.     

Efficacy and safety of perioperative infusion of levosimendan in patients with compromised cardiac function undergoing open-heart surgery: importance of early use.

OBJECTIVE: Levosimendan is a promising new inotrope. We investigate the proper time for its infusion during or after open-heart surgery to avoid complications related with low-output syndrome and high dosage of inotropes. METHODS: Forty-five consecutive patients were randomised to receive levosimendan in addition to the conventional therapy, its infusion starting in the operating theatre (Group OT) or in the ICU (Group ICU) when low-output syndrome was certified and were consequently dependent on classical inotropic support and IABP. Levosimendan was infused at a rate of 0.1 microg/kg min without loading dose, the infusion being for at least 24h to a maximum 48 h. RESULTS: Levosimendan was well tolerated, with the simultaneous infusion of norepinephrine if required. Its efficacy was identical in both groups with improvement in the haemodynamic and functional status of patients (amelioration of stroke volume, cardiac index and mixed venous blood oxygen saturation, increase of left ventricular ejection fraction by echo study, de-escalation of traditional inotropes, subtraction of IABP and reduction in BNP plasma levels). The ICU stay and hospital stay were significantly decreased in patients of Group OT, compared to patients of Group ICU. Four patients died because of multiple organs dysfunction syndrome (MODS) due to sepsis (all patients of Group ICU). CONCLUSION: Levosimendan is a safe and efficient choice in the management of low-output syndrome during and after open-heart surgery. The shortening of hospitalisation and the trend for better outcome confirm its clear superiority when the infusion starts from the operating theatre.     

Limited feedback and video tutorials optimize learning and resource utilization during laparoscopic simulator training

BACKGROUND: The purpose of this study was to determine the impact of instructor feedback and video tutorials on skill acquisition during proficiency-based laparoscopic suturing training. METHODS: Performance data from a prospectively maintained database were reviewed for three groups of novices (n = 34 medical students) who completed the same proficiency-based laparoscopic suturing curriculum on a Fundamentals of Laparoscopic Surgery-type videotrainer model as part of two separate institutional review board-approved, randomized controlled trials. Group I (n = 9) watched the video tutorial once and received intense feedback during each training session; Group II (n = 13) watched the video tutorial once and received limited feedback (<10 min per session); Group III (n = 12) watched the video tutorial several times and also received limited feedback (<10 min per session). Feedback was given by the same instructor and was quantified on a 0 (none) to 4 (extensive) Likert scale. RESULTS: Baseline characteristics were similar for all groups. All participants achieved the proficiency level (512) on two consecutive attempts. Group III required the shortest training time and number of repetitions to reach proficiency, with statistically significant differences compared with Group I (P < 0.02). This strategy led to a cost savings of $139 per trainee. CONCLUSIONS: Limited instructor feedback appears to be superior to intense feedback during proficiency-based laparoscopic simulator training. Coupled with video tutorials, this type of feedback may accelerate learning and improve resource utilization by minimizing the need for instructor involvement.     

Pediatric scaphoid nonunion

PURPOSE: To report the outcome of pediatric scaphoid nonunions treated with a Herbert screw and bone graft. METHODS: This is a retrospective review of 12 cases of scaphoid nonunion in 12 skeletally immature patients treated with a uniform approach consisting of open reduction, iliac crest bone grafting and Herbert screw fixation. All patients were boys and presented with nonunions of the scaphoid waist. The final follow-up evaluation was at a mean of 32 months, ranging from 22 to 45 months, and consisted of assessing anatomic snuffbox tenderness, wrist arc of motion, grip strength, calculation of the Modified Mayo Wrist score, and assessment of union based on plain radiographs. RESULTS: At the latest follow-up evaluation, all patients were pain free (including absence of snuffbox tenderness) except one who experienced slight discomfort during extreme activities. There was no statistically significant difference in the arc of motion between the surgically treated and healthy sides, and the average grip strength was 96% that of the contralateral extremity. Clinical and radiographic union was present in all cases at a mean of 3.4 months after surgery. The Modified Mayo Wrist score was excellent in 11 patients and good in 1. There were no complications. CONCLUSIONS: Open reduction and internal fixation with a Herbert screw reliably obtained union in all patients. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.     

The effects of iloprost on colonic anastomotic healing in rats under obstructive ileus conditions

Background

The aim of this study was to investigate the effects of iloprost, on colonic anastomotic healing in rats, under obstructive ileus conditions.

Materials and methods

Eighty male Albino rats were randomized into four groups of 20 animals each. They underwent colonic resection followed by an inverted anastomosis. The rats of group 1 (control) and group 2 (ileus) received 3 mL of saline 0.9% intraperitoneally and those of group 3 (iloprost), and group 4 (ileus + iloprost) iloprost (2 μg/kg of body weight), immediately postoperatively and daily until the day of sacrifice. Each group was further divided into two equal subgroups, depending on the day of sacrifice. The animals of subgroup “a” were sacrificed on the fourth postoperative day, whereas those of “b” on the eighth day. Macroscopic and histologic assessment was performed, whereas anastomotic bursting pressures and the tissue concentrations in hydroxyproline and collagenase I were evaluated.

Results

Means of bursting pressure, neoangiogenesis, fibroblast activity, and hydroxyproline concentration were significantly increased in group 4 compared with group 2. In addition, on the fourth postoperative day, the inflammatory cell infiltration and the collagenase I concentration were significantly decreased in group 4 compared with group 2. Moreover, on the eighth postoperative day, collagen deposition was significantly increased in group 4 compared with group 2.

Conclusions

Iloprost after intraperitoneal administration reverses the negative effect of obstructive ileus. It promotes not only the angiogenic activity but also collagen formation, resulting in increased bursting pressures on the fourth and eighth postoperative days.     

Circulating angiogenic biomolecules at rest and in response to upper-limb exercise in individuals with spinal cord injury

Objective

Individuals with spinal cord injury (SCI) show structural and functional vascular maladaptations and muscle loss in their lower limbs. Angiogenic biomolecules play important roles in physiological and pathological angiogenesis, and are implicated in the maintenance of muscle mass. This study examined the responses of angiogenic molecules during upper-limb aerobic exercise in patients with SCI and in able-bodied (AB) individuals.

Methods

Eight SCI patients with thoracic lesions (T₆–T₁₂, ASIA A) and eight AB individuals performed an arm-cranking exercise for 30 minutes at 60% of their VO_2max. Plasma concentrations of vascular endothelial growth factor (VEGF-A₁₆₅), VEGF receptor 1 (sVEGFr-1), VEGF receptor 2 (sVEGFr-2), metalloproteinase 2 (MMP-2), and endostatin were measured at rest, after exercise, and at 1.5 and 3.0 hours during recovery.

Results

The two-way analysis of variance showed non-significant main effects of “group” and significant main effects of “time/exercise” for all angiogenic biomolecules examined (P < 0.01–0.001). The arm-cranking exercise significantly increased plasma concentrations of VEGF, sVEGFr-1, sVEGFr-2, MMP-2, and endostatin in both groups (P < 0.001–0.01). The magnitude of the increase was similar in both patients with SCI and AB individuals, as shown by the non-significant group × time interaction for all angiogenic parameters.

Conclusions

Upper-limb exercise (arm-cranking for 30 minutes at 60% of VO_2max) is a sufficient stimulus to trigger a coordinated circulating angiogenic response in patients with SCI. The response of angiogenic molecules to upper-limb aerobic exercise in SCI appears relatively similar to that observed in AB individuals.     

Primary Enteric-Type Mucinous Adenocarcinoma of the Urethra in a Patient With Ulcerative Colitis

Primary carcinoma of the male urethra accounts for less than 1% of malignancies in men. Mucinous adenocarcinoma of the urethra is extremely rare, and its biologic behavior is poorly understood. We present herein a rare case of mucinous urethral adenocarcinoma in a male patient with longstanding ulcerative colitis and multiple sclerosis. The patient presented with a voluminous pelvic mass; core biopsy of the lesion demonstrated a mucus-producing adenocarcinoma. Given the patient''s history of subtotal colectomy, preoperative diagnosis was oriented towards a rectal stump adenocarcinoma. The patient underwent a pelvic exenteration: surprisingly, histology marked the prostatic urethra as the primary lesion site.Key words: Urethra, Adenocarcinoma, Mucinous, Ulcerative colitisPrimary enteric-type mucinous adenocarcinoma of the urethra is an extremely rare entity with aggressive clinical course regardless of treatment. Interestingly, it has been implied that inflammatory bowel disease and multiple sclerosis share common mechanisms of impaired histocompatibility. Moreover, patients with inflammatory bower disease who receive prolonged immunosuppression such as azathioprine tend to increasingly develop urinary tract malignancies. We report herein a complex case of enteric-type mucinous adenocarcinoma of urethral origin in a male with a longstanding history of ulcerative colitis and multiple sclerosis.