Minimally invasive treatment of urinary fistulas using n-butyl-2-cyanoacrylate : a valid first option

BACKGROUND: A few single case reports and only one clinical series have been published so far about the use of N-butyl-2-cyanoacrylate in the treatment of urinary fistulas persisting after conventional urinary drainage. CASE PRESENTATION: We treated five patients with a mean age of 59.2 years presenting iatrogenic urinary fistulas which persisted following conventional drainage manouvres. There were 3 calyceal fistulas following open, laparoscopic and robotic removal of renal lesions respectively, one pelvic fistula after orthotopic ileal neobladder and a bilateral dehiscence of uretero-sigmoidostomy. We used open-end catheters of different sizes adopting a retrograde endoscopic approach for cyanoacrylate injection in the renal calyces, while a descending percutaneous approach via the pelvic drain tract and bilateral nephrostomies respectively was used for the pelvic fistulas. Fluoroscopic control was always used during the occlusion procedures. The amount of adhesive injected ranged between 2 and 5 cc and in one case the procedure was repeated. With a median follow-up of 11 months we observed clinical and radiological resolution in 4 cases (80%), while a recurrent and infected calyceal fistula after laparoscopic thermal renal damage during tumor enucleoresection required nephrectomy. No significant complications were documented. CONCLUSIONS: In an attempt to spare further challenging surgery in patients that had been already operated on recently, minimally invasive occlusion of persistent urinary fistulas with N-butyl-2-cyanoacrylate represents a valid first line treatment, justified in cases when the urinary output is not excessive and there is a favorable ratio between the length and diameter of the fistulous tract

Critical issues in the determination of the bentonite cation exchange capacity

The swelling pressure and transport properties of bentonites are controlled by the electric charge density of solid particles, which is commonly estimated from the laboratory measurement of the cation exchange capacity (CEC). However, the standard ammonium displacement method for CEC determination does not take into account the fabric changes that occur in bentonites under exposure to high salt concentration solutions. A series of laboratory tests was conducted to assess the relevance of such a critical issue, by varying the concentration of the extracting KCl solution with respect to that of the standard test. The obtained results show that the release of the adsorbed ammonium cations depends on the bentonite fabric, which is controlled by the KCl concentration. As a consequence, the ammonium displacement method may provide an unrepresentative estimate of the CEC of bentonites. The methylene blue titration method, despite its apparently more limited accuracy, instead seems to provide a more reliable estimation of the CEC, as the bentonite fabric is maintained dispersed during the test

Complete intraperitoneal displacement of a double J stent: a first case.

OBJECTIVES: Ureteral double-J stents are known to migrate proximally and distally within the urinary tract, while perforation and stent displacement are uncommon. Possible mechanisms of displacement are either original malpositioning with ureteral perforation or subsequent fistula and erosion of the excretory system, due to infection or long permanence of the device. We present the unique case of complete intraperitoneal stent migration in a 59-year-old caucasian male without evidence of urinary fistula at the moment of diagnosis, so far an unreported complication. MATERIALS AND METHODS: Eight months after the placement of a double-J stent for lower right ureteral stricture at a district hospital, the patient came at our observation for urosepsis and hydro-uretero-nephrosis. A CT scan demonstrated intraperitoneal migration of the stent outside the urinary tract. Cystoscopy failed to visualize the lower extremity of the stent, a percutaneous nephrostomy was placed to drain the urinary system and the stent was removed through a small abdominal incision on the right lower quadrant. RESULTS: In our case we presume that during the positioning manoeuvre the guide wire perforated simultaneously the lower ureteral wall and the pelvic peritoneum, and that once the upper end of the stent was coiled, the lower extremity was also attracted intraperitoneally. The lack of pain due to the spinal lesion concurred to this unusual complication. CONCLUSIONS: We must be aware that ureteral double J stents may be found displaced even inside the peritoneal cavity, and that the use of retrograde pyelography during placement is of paramount importance to exclude misplacement of an apparently normally coiled upper extremity of the stent

Accuracy of a flash glucose monitoring system in cats and determination of the time lag between blood glucose and interstitial glucose concentrations

Background: The FreeStyle Libre (Abbott Laboratories) is a flash glucose monitoring system (FGMS) that measures interstitial glucose concentration (IG). The system is factory-calibrated, easy to use, inexpensive, and could be useful for monitoring diabetic cats. Objectives: To evaluate the analytical and clinical accuracy of the FGMS in cats and establish the lag-time between IG and blood glucose concentration (BG). Animals: Twenty client-owned diabetic cats and 7 purpose-bred healthy cats. Methods: Prospective study. Blood glucose concentration was measured using a portable glucose meter validated for use in cats that served as a reference method for IG, as measured by FGMS. In diabetic cats, data were collected for sensor wearing time with different methods of application and accuracy across glycemic ranges. Accuracy was determined by fulfillment of ISO15197:2013 criteria. In healthy cats, lag-time between IG and BG was established after IV administration of exogenous glucose. Results: Good agreement between IG and BG was obtained (r =.93). Analytical accuracy was not achieved, whereas clinical accuracy was demonstrated with 100% of the results in zones A + B of the Parkes consensus error grid analysis. In the immediate 30 minutes after an IV bolus of glucose, when BG was increasing rapidly (approximately 2%/min), IG increased slowly, resulting in a difference of as much as 579 mg/dL, and no positive correlation between BG and IG was found. Conclusions and Clinical Importance: The FGMS did not fulfill ISO requirements but is sufficiently accurate for glucose monitoring in cats, while considering the lag between IG and BG during periods of rapid changes in BG

C-MYC, HIF-1α, ERG, TKT, and GSTP1: an Axis in Prostate Cancer?

To analyze putative biomarkers for prostate cancer (PCA) characterization, the second leading cause of cancer-associated mortality in men. Quantification of the expression level of c-myc and HIF-1α was performed in 72 prostate cancer specimens. A cohort of 497 prostate cancer patients from The Cancer Genome Atlas (TCGA) database was further analyzed, in order to test our hypothesis. We found that high c-myc level was significantly associated with HIF-1α elevated expression (p = 0.008) in our 72 samples. Statistical analysis of 497 TCGA prostate cancer specimens confirmed the strong association (p = 0.0005) of c-myc and HIF-1α expression levels, as we found in our series. Moreover, we found high c-myc levels significantly associated with low Glutatione S-transferase P1 (GSTP1) expression (p = 0.01), with high Transketolase (TKT) expression (p < 0.0001). High TKT levels were found in TCGA samples with low GSTP1 mRNA (p < 0.0001), as shown for c-myc, and with ERG increased expression (p = 0.02). Finally, samples with low GSTP1 expression displayed higher ERG mRNA levels than samples with high GSTP1 score (p < 0.0001), as above shown for c-myc. Our study emphasizes the notion of a potential value of HIF-1α and c-myc as putative biomarkers in prostate cancer; moreover TCGA data analysis showed a putative crosstalk between c-myc, HIF-1α, ERG, TKT, and GSTP1, suggesting a potential use of this axis in prostate cancer

Gastrin-Releasing Peptide Receptor in Low Grade Prostate Cancer: Can It Be a Better Predictor Than Prostate-Specific Membrane Antigen?

The aim of the present study was to evaluate whether prostate cancer (PC) patients can be accurately classified on the bases of tissue expression of gastrin-releasing peptide receptor (GRPR) and prostate-specific membrane antigen (PSMA). This retrospective study included 28 patients with PC. Formalin-fixed paraffin-embedded samples were used for diagnosis. Immunohistochemistry staining techniques were used to evaluate PSMA and GRPR expression (both number of cells expressed and % of area stained). To assess the independent associations among selected variables, a multi-dimensional scaling (MDS) analysis was used. It was found that the PSMA expression was inversely correlated with GRPR expression. Only the number of cells expressing GRPR was significantly related to the Gleason score. Both the percentage of area expressing GRPR and the number of cells expressing PSMA were close to reaching significance at the 0.05 level. MDS provided a map of the overall, independent association confirming that GRPR and PSMA represent inversely correlated measures of the same dimension. In conclusion, our data showed that GRPR expression should be evaluated in prostate biopsy specimens to improve our ability to detect PC with low grades at the earliest phases of development. Considering that GRPRs appear to be directly involved in the mechanisms of tumor proliferation, advancements in nuclear medicine radiotherapy can focus on this receptor to improve the therapeutic approach to PC. Further studies in our laboratory will investigate the molecular mechanisms of activation based on GRPR

Prognostic impact of bone invasion in canine oral malignant melanoma treated by surgery and anti-CSPG4 vaccination: A retrospective study on 68 cases (2010–2020)

Prognosis of canine oral malignant melanoma encompasses clinical, histological and immunohistochemical parameters. The aim of this study was to evaluate the prognostic impact of bone invasion in oral canine melanoma. Sixty‐eight dogs bearing oral melanoma staged II and III that underwent surgery and anti‐CSPG4 electrovaccination, with available histological data and a minimum follow up of minimum 1 year, were retrospectively selected. Bone invasion was detected on imaging and/or histology. Median survival time of dogs with evidence of bone invasion (group 1) was 397 days and significantly shorter compared with dogs with oral melanomas not invading the bone (group 2, 1063 days). Dogs with tumours localised at the level of the cheek, lip, tongue and soft palate (soft tissue ‐ group 3) lived significantly longer compared with dogs having tumours within the gingiva of the maxilla or mandible (hard tissue ‐ group 4) with a median survival time of 1063 and 470 days, respectively. Within group 4, the subgroup of dogs with tumours not invading the bone (group 5) showed a significant prolonged survival time (972 days) in comparison with dogs of group 1 (bone invasion group). Similar results were obtained for the disease‐free intervals amongst the different groups. Statistical analysis showed that Ki67 and mitotic count were correlated with shorter survival in patients of group 1 (with bone invasion). Bone invasion should always be assessed since it appears to be a negative prognostic factor

Difference in outcome between curative intent vs marginal excision as a first treatment in dogs with oral malignant melanoma and the impact of adjuvant CSPG4-DNA electrovaccination: A retrospective study on 155 cases

Canine oral malignant melanoma is locally invasive and highly metastatic. At present, the best option for local control is en bloc excision followed by radiation if excision margins are incomplete. Adjuvantly, the role of chemotherapy is dubious while immunotherapy appears encouraging. This retrospective study evaluated 155 dogs with oral malignant melanomas (24 stage I, 54 stage II, 66 stage III and 11 stage IV) managed in a single institution. The aim was to evaluate the differences in median survival time (MST) and disease‐free interval (DFI) between dogs which, at presentation, were treated surgically with a curative intent (group 1) vs those marginally excised only (group 2). MST in group 1 was longer than in group 2 (594 vs 458 days), but no significant difference was found (P = .57); a statistical difference was, however, found for DFI (232 vs 183 days, P = .008). In the subpopulation of vaccinated dogs, the impact of adjuvant anti‐CSPG4 DNA electrovaccination was then evaluated (curative intent, group 3, vs marginal, group 4); a significant difference for both MST (1333 vs 470 days, respectively, P = .03) and DFI (324 vs 184 days, respectively, P = .008) was found. Progressive disease was significantly more common in dogs undergoing marginal excision than curative intent excision for both the overall population (P = .03) and the vaccinated dogs (P = .02). This study pointed out that, after staging, wide excision together with adjuvant immunotherapy was an effective approach for canine oral malignant melanoma

Seismic interferometry applied to local fracture seismicity recorded at Planchón-Peteroa Volcanic Complex, Argentina-Chile

Although the Planchon-Peteroa Volcanic Complex (PPVC) has undergone many hazardous eruptions, only a small number of geological, geochemical, and geophysical studies have been performed to describe this active volcanic system. In order to characterize the subsurface structures present at the PPVC, we applied seismic interferometry to fracture seismicity originating in this volcanic complex and along active geologic faults located nearby. We utilized seismic data recorded by two arrays of stations deployed in Argentina and Chile. Nine of these stations (three in Chile and six in Argentina) recorded data simultaneously and were used for this application. Only seismic events with energy arriving (sub) vertically to the stations were chosen for processing. According to the magnitude and the location of the selected seismic events, relocated seismic sources were used for the Chilean stations while, for the Argentine stations, only seismic sources located near that array were used. We obtained seismic evidence of the location of the subsurface reflectors underneath each station using zero-offset reflection responses retrieved from seismic interferometry by autocorrelation of (time windows extracted from) the selected seismic events. Then, applying a comparative analysis between the seismic results and the available geological information, we imaged the shallow subsurface of the area enclosed by the Chilean stations, and also by the Argentine stations. The results are consistent with the available geological information, provide accurate depth values for several subsurface discontinuities, indicate areas of higher heterogeneity, and support the emplacement of a magma body at ∼4 km depth from the surface. This work shows the first application of a novel variation of seismic interferometry based on autocorrelations to local-earthquake data recorded in a volcanic area.Facultad de Ciencias Astronómicas y Geofísica