Treatment of Ureteroarterial Fistulae with Covered Vascular Endoprostheses and Ureteral Occlusion

Background Ureteroarterial fistulae (UAFs) are a rare entity, often difficult to identify, and associated with a high mortality rate. This fact has been attributed to a delay in diagnosis and treatment. Five conditions that can predispose to the development of this uncommon entity have been described: prior pelvic surgery, prolonged ureteral stenting, radiation therapy, previous vascular surgery and vascular pathology.Methods We present 4 patients with UAFs and at least three of the above-mentioned conditions. Ureteral ischemia and subsequent necrosis promote the formation of these fistulae. The constant pulsation of the iliac artery is transmitted to an already compromised ureter containing a stiff intraluminal foreign body, resulting in pressure necrosis, most likely where the ureter crosses the iliac artery.Results and Conclusion Cases were managed percutaneously with a combination of the deployment of a covered prosthesis and, when needed, with mechanical occlusion of the ureter. Hematuria stopped in all the patients with no evidence of immediate rebleeding. One patient presented a new episode of vaginal bleeding 13 months after endograft placement and ureteral embolization. Arteriography showed the presence of a hypogastric artery pseudoaneurysm that was occluded using coils. No new bleeding has occurred in this patient 12 months after the second embolization. At present all 4 patients are alive with follow-up periods of 5, 9, 11 and 25 months since the first procedure.     

In vitro effects of platelet factor 4 on normal human neutrophil functions

Platelet factor (PF4) prepared from human outdated platelets by heparinagarose affinity chromatography was confirmed to be chemotactic for human neutrophils and in a concentration-dependent fashion caused significant release of lysosomal enzymes (myeloperoxidase, lysozyme, beta-glucuronidase) from human neutrophils treated with cytochalasin B. Lysosomal enzyme release from PF4-stimulated neutrophils was rapid and reached a plateau by 1-3 min. PF4 did not cause release of the cytoplasmic enzyme lactate dehydrogenase which indicates that exocytosis of granule-containing lysosomal enzymes did not result from cytolysis. In contrast, superoxide anion generation from human neutrophils stimulated with PF4 was undetectable even at the highest PF4 concentration tested (2 X 10(-5) M). Pretreatment of neutrophils with PF4 caused significant increased adherence of neutrophils to plastic surfaces and cultured pulmonary artery endothelial cells. The concentration of PF4 that elicited neutrophil chemotaxis, lysosomal enzyme release and increased adherence is slightly higher than those concentrations found in normal human sera. However, the results suggest that PF4 may be an important mediator in neutrophil-platelet interactions and the induction of acute inflammation especially at sites of platelet microthrombi where the concentration of PF4 would be elevated.     

Post-injury immunosuppression and secondary infections are caused by an AIM2 inflammasome-driven signaling cascade

1. Download : Download high-res image (145KB)
2. Download : Download full-size image

     

Opening new horizons in regenerative dermatology using platelet‐based autologous therapies

Biological therapeutic therapies are gaining the attention of scientists and medical doctors. Accumulating evidence suggests that blood‐derived autologous therapies are safe and effective treatments for skin repair and wound healing. The fibrin network formed after plasmatic activation and the autologous growth factors released when platelets degranulate constitute a real biological medicine that has been shown to promote cell recruitment, stimulate new blood vessel formation, reduce inflammation as well as protect from local infections. This perspective highlights recent basic and clinical results published on blood‐derived autologous therapies in the field of regenerative dermatology and discusses potential challenges and future prospects.     

Frequency analyses of EMG power spectra of anterior temporal and masseter muscles in children and adults

To study the functional change of masticatory muscles during growth and development, frequency analyses of surface electromyogram (EMG) power spectra were carried out. The subjects were six children (five males and one female), aged 4.5 +/- 0.2 years, having full deciduous dentition (Hellman's dental age IIA) and six adults (four males and two females), aged 27.7 +/- 3.8 years, having full permanent dentition. EMG signals were recorded bilaterally by using bipolar silver-surface electrodes from the anterior temporal and masseter muscles while the subjects were chewing gum and while performing maximum clenching in the intercuspal position. A fast Fourier transform algorithm was used to obtain the power-spectral density function and the power spectra of the EMG signals. Since the total power value from 62.5 to 1000 Hz was 100 percent, the frequencies at 25, 50, 75, and 90 percent of the cumulative power were calculated. The results showed that the frequencies at every percent of the cumulative power were age-dependent and that the EMG power spectra patterns in adult muscles were shifted to significantly lower frequencies than those in child muscles. The shift was probably caused by differences in the proportion of fiber type and fiber size between muscles of children and adults.     

Squamous cell carcinoma of the male urethra mimicking a paravertebral abscess.

In the context of a misleading diagnosis of paraurethral abscess, we report a case of unrecognized metastatic squamous cell carcinoma of the male urethra that mimicked a picture of paravertebral abscess with accompanying massive caval vein thrombosis. Fine needle aspiration cytology of both paravertebral abscess and urethral nodule allowed the diagnosis. This report calls the attention of clinicians to think of a malignant process in case of a paravertebral abscess. Fine needle aspiration cytology once more proves a useful tool in the diagnosis of unsuspected malignancies.     

Blastocyst culture after repeated failure of cleavage-stage embryo transfers: a comparison of day 5 and day 6 transfers

OBJECTIVE: To evaluate the efficacy of blastocyst transfer among patients with at least three previous cleavage-stage embryo transfer failures and to compare pregnancy and implantation rates of blastocysts according to the day of embryo transfer (day 5 or day 6 after oocyte retrieval). DESIGN: Retrospective clinical study. SETTING: Private ART center. PATIENT(S): One hundred forty-eight patients (with at least three failed cleavage-stage embryo transfers) undergoing blastocyst-stage embryo transfer. INTERVENTION(S): Embryos were grown for up to 6 days and only blastocyst-stage (cavitating) embryos were transferred on either day 5 or day 6 after oocyte retrieval. MAIN OUTCOME MEASURE(S): Clinical pregnancy and implantation rates. RESULT(S): Blastocysts transferred on day 5 implanted almost five times the rate of those transferred on day 6 (23% vs. 5%). Pregnancy rates were triple as high among the 73 day 5 patients compared to the 63 day 6 transfer patients (38% vs. 11%). The number of blastocysts formed and per embryo rates of blastocyst formation were both significantly higher for patients undergoing day 5 transfers: more blastocysts developed (3.0 vs. 2.1) and more were transferred (3.0 vs. 1.9). In addition, blastocyst formation rates were 46% and 33%, respectively, for both groups of patients. CONCLUSION(S): Blastocyst transfer (preferably on day 5 after retrieval) appears to be a successful and improved alternative for patients with multiple failed IVF attempts. Moreover, with blastocyst transfer there should be a reduction in multiple pregnancy risk, because fewer embryos have to be transferred.     

Increased phagocytic nicotinamide adenine dinucleotide phosphate oxidase-dependent superoxide production in patients with early chronic kidney disease

BACKGROUND: Oxidative stress has been implicated in the pathogenesis of atherosclerosis that develops in patients with advanced chronic kidney disease (CKD). This study was designed to investigate whether a relationship exists between phagocytic nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-dependent superoxide anion (*O2-) production and subclinical atherosclerosis in patients with early CKD. METHODS: Superoxide production was assayed by chemiluminescence under baseline and stimulated conditions on mononuclear cells obtained from asymptomatic patients with stage 1 to 2 CKD (N=22) and healthy controls (N=21). Ultrasonographic determination of carotid intima-media thickness (IMT) was used to assess the presence of atherosclerosis. RESULTS: Although there were no differences in baseline *O2- production between controls and patients, the *O2- production in phorbol myristate acetate-stimulated mononuclear cells was increased (P<0.05) in patients compared with controls. The phorbol myristate acetate-induced *O2- production was completely abolished by apocynin, a specific inhibitor of NADPH oxidase. A direct correlation (r=0.441, P<0.05) was found between plasma insulin levels and NADPH oxidase-mediated *O2- production in patients. Carotid IMT was higher (P<0.005) in patients than in controls. Carotid IMT values above the upper normal limit in controls were found in 70% and 40% of patients with increased or normal NADPH oxidase-mediated *O2- production, respectively. CONCLUSION: Generation of *O2- that is mainly dependent on NADPH oxidase is abnormally enhanced in patients with early CKD. It is suggested that this alteration could be related to the development of subclinical atherosclerosis in these patients.