776 resultados para Diálisis Peritoneal
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The identification of 15N-labeled 3-nitrotyrosine (NTyr) by gas chromatography/mass spectroscopy in protein hydrolyzates from activated RAW 264.7 macrophages incubated with 15N-L-arginine confirms that nitric oxide synthase (NOS) is involved in the nitration of protein-bound tyrosine (Tyr). An assay is presented for NTyr that employs HPLC with tandem electrochemical and UV detection. The assay involves enzymatic hydrolysis of protein, acetylation, solvent extraction, O-deacetylation, and dithionite reduction to produce an analyte containing N-acetyl-3-aminotyrosine, an electrochemically active derivative of NTyr. We estimate the level of protein-bound NTyr in normal rat plasma to be approximately 0-1 residues per 10(6) Tyr with a detection limit of 0.5 per 10(7) Tyr when > 100 nmol of Tyr is analyzed and when precautions are taken to limit nitration artifacts. Zymosan-treated RAW 264.7 cells were shown to have an approximately 6-fold higher level of protein-bound NTyr compared with control cells and cells treated with N(G)-monomethyl-L-arginine, an inhibitor of NOS. Intraperitoneal injection of F344 rats with zymosan led to a marked elevation in protein-bound NTyr to approximately 13 residues per 10(6) Tyr, an approximately 40-fold elevation compared with plasma protein of untreated rats; cotreatment with N(G)-monomethyl-L-arginine inhibited the formation of NTyr in plasma protein from blood and peritoneal exudate by 69% and 53%, respectively. This assay offers a highly sensitive and quantitative approach for investigating the role of reactive byproducts of nitric oxide in the many pathological conditions and disease states associated with NO(X) exposure such as inflammation and smoking.
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TNFalpha (TNF) critically regulates inflammation-driven atherosclerosis. Because the transmembrane (tmTNF) and soluble (sTNF) forms of TNF possess distinct immuno-modulatory properties, we hypothesized that they might differentially regulate atherosclerosis progression. Three groups of male ApoE(-/-) mice were studied: one expressing wild-type TNF (WT-TNF); one expressing exclusively a mutated non-cleavable form of TNF (KI-TNF); and one deficient in TNF (KO-TNF). Mice aged 5 weeks were fed the high-fat diet for 5 (T5) and 15 weeks (T15) or a standard chow diet for 15 weeks. At T5, in mice fed the high-fat diet, no significant differences in lesion area were observed among the three groups, either in valves or in aortas. At T15, lesion areas in valves were significantly lower in KO-TNF mice compared with those in WT-TNF mice, whereas in KI-TNF mice, they were intermediate between KO- and WT-TNF mice but not significantly different from these two groups. In aortas, lesions in KI-TNF were comparable to those of KO-TNF, both being significantly lower than those in WT-TNF. Theses differences were not linked to circulating lipids, or to macrophage, actin, and collagen contents of lesions. At T15, in mice fed the chow diet, lesion areas in valves and the aortic arch were not significantly different between the three groups. Levels of IL-6, IFNgamma, IL-10, and Foxp3 mRNAs in spleens and production of IL-6, IL-10, MCP-1, RANTES, and TNFR-2 by peritoneal macrophages at T15 of the high-fat diet showed a decrease in pro-inflammatory status, more marked in KO-TNF than in KI-TNF mice. Apoptosis was reduced only in KO-TNF mice. In conclusion, these data show that TNF effects on atherosclerosis development are detectable at stages succeeding fatty streaks and that wild-type TNF is superior to tmTNF alone in promoting atherosclerosis. TNF-dependent progression of atherosclerosis is probably linked to the differential production of pro-inflammatory mediators whether tmTNF is preponderant or essentially cleaved. Copyright (c) 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley ; Sons, Ltd.
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A 70-year-old man known for recurrent abdominal gastrointestinal stroma tumor presented with a suspicious peritoneal mass demonstrated by an abdominal CT scan. Whole-body PET showed focal FDG uptake in the right hip, whereas the peritoneal mass was FDG negative. Histologic work-up of the PET positive lesion surprisingly revealed a giant cell tumor of the tendon sheath. The benignity of the peritoneal mass was confirmed by its disappearance in repeated CT scans. In general, focally increased FDG uptake should be subject to further investigations, especially in localizations that are not consistent with typical metastatic pathways of the former primary tumor.
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Over the past 30 years, benzimidazoles have increasingly been used to treat cystic echinococcosis (CE). The efficacy of benzimidazoles, however, remains unclear. We systematically searched MEDLINE, EMBASE, SIGLE, and CCTR to identify studies on benzimidazole treatment outcome. A large heterogeneity of methods in 23 reports precluded a meta-analysis of published results. Specialist centres were contacted to provide individual patient data. We conducted survival analyses for cyst response defined as inactive (CE4 or CE5 by the ultrasound-based World Health Organisation [WHO] classification scheme) or as disappeared. We collected data from 711 treated patients with 1,308 cysts from six centres (five countries). Analysis was restricted to 1,159 liver and peritoneal cysts. Overall, 1-2 y after initiation of benzimidazole treatment 50%-75% of active C1 cysts were classified as inactive/disappeared compared to 30%-55% of CE2 and CE3 cysts. Further in analyzing the rate of inactivation/disappearance with regard to cyst size, 50%-60% of cysts <6 cm responded to treatment after 1-2 y compared to 25%-50% of cysts >6 cm. However, 25% of cysts reverted to active status within 1.5 to 2 y after having initially responded and multiple relapses were observed; after the second and third treatment 60% of cysts relapsed within 2 y. We estimated that 2 y after treatment initiation 40% of cysts are still active or become active again. The overall efficacy of benzimidazoles has been overstated in the past. There is an urgent need for a pragmatic randomised controlled trial that compares standardized benzimidazole therapy on responsive cyst stages with the other treatment modalities.
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Annexin-1 (ANXA1) is a mediator of the anti-inflammatory actions of endogenous and exogenous glucocorticoids (GC). The mechanism of ANXA1 effects on cytokine production in macrophages is unknown and is here investigated in vivo and in vitro. In response to LPS administration, ANXA1(-/-) mice exhibited significantly increased serum IL-6 and TNF compared with wild-type (WT) controls. Similarly, LPS-induced IL-6 and TNF were significantly greater in ANXA1(-/-) than in WT peritoneal macrophages in vitro. In addition, deficiency of ANXA1 was associated with impairment of the inhibitory effects of dexamethasone (DEX) on LPS-induced IL-6 and TNF in macrophages. Increased LPS-induced cytokine expression in the absence of ANXA1 was accompanied by significantly increased LPS-induced activation of ERK and JNK MAPK and was abrogated by inhibition of either of these pathways. No differences in GC effects on MAPK or MAPK phosphatase 1 were observed in ANXA1(-/-) cells. In contrast, GC-induced expression of the regulatory protein GILZ was significantly reduced in ANXA1(-/-) cells by silencing of ANXA1 in WT cells and in macrophages of ANXA1(-/-) mice in vivo. GC-induced GILZ expression and GC inhibition of NF-kappaB activation were restored by expression of ANXA1 in ANXA1(-/-) cells, and GILZ overexpression in ANXA1(-/-) macrophages reduced ERK MAPK phosphorylation and restored sensitivity of cytokine expression and NF-kappaB activation to GC. These data confirm ANXA1 as a key inhibitor of macrophage cytokine expression and identify GILZ as a previously unrecognized mechanism of the anti-inflammatory effects of ANXA1.
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AIM: The mTOR-inhibitor rapamycin has shown antitumor activity in various tumors. Bedside observations have suggested that rapamycin may be effective as a treatment for colorectal carcinomatosis. METHODS: We established an orthotopic syngenic model by transplanting CT26 peritoneal tumors in Balb/C mice and an orthotopic xenograft model by transplanting SW620 peritoneal tumors in nu/nu mice. Expression levels of tissue inhibitor of matrix-metalloproteinases 1 (TIMP-1) in the tumor and serum was determined by enzyme-linked immunosorbent assay. RESULTS: Rapamycin significantly suppressed growth of syngenic and xenografted peritoneal tumors. The effect was similar with intraperitoneal or oral rapamycin administration. Tumor suppression was further enhanced when rapamycin was combined with 5-fluorouracil and/or oxaliplatin. The combination treatment showed no acute toxicity. TIMP-1 serum levels correlated well (CC = 0.75; P < 0.01) with rapamycin treatment. CONCLUSIONS: Rapamycin suppressed advanced stage colorectal cancer, even with oral administration. Combining rapamycin with current chemotherapy regimens significantly increased antitumor efficacy without apparent toxicity. The treatment efficacy correlated with serum TIMP-1 levels, suggesting its potential as a surrogate marker in future clinical trials.
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Alveolar echinococcosis (AE) in humans is a parasitic disease characterized by severe damage to the liver and occasionally other organs. AE is caused by infection with the metacestode (larval) stage of the fox tapeworm Echinococcus multilocularis, usually infecting small rodents as natural intermediate hosts. Conventionally, human AE is chemotherapeutically treated with mebendazole or albendazole. There is, however still the need for improved chemotherapeutical options. Primary in vivo studies on drugs of interest are commonly performed in small laboratory animals such as mice and Mongolian jirds, and in most cases, a secondary infection model is used, whereby E. multilocularis metacestodes are directly injected into the peritoneal cavity or into the liver. Disadvantages of this methodological approach include risk of injury to organs during the inoculation and, most notably, a limitation in the macroscopic (visible) assessment of treatment efficacy. Thus, in order to monitor the efficacy of chemotherapeutical treatment, animals have to be euthanized and the parasite tissue dissected. In the present study, mice were infected with E. multilocularis metacestodes through the subcutaneous route and were then subjected to chemotherapy employing albendazole. Serological responses to infection were comparatively assessed in mice infected by the conventional intraperitoneal route. We demonstrate that the subcutaneous infection model for secondary AE facilitates the assessment of the progress of infection and drug treatment in the live animal.
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Background: High grade serous carcinoma whether ovarian, tubal or primary peritoneal, continues to be the most lethal gynecologic malignancy in the USA. Although combination chemotherapy and aggressive surgical resection has improved survival in the past decade the majority of patients still succumb to chemo-resistant disease recurrence. It has recently been reported that amplification of 5q31-5q35.3 is associated with poor prognosis in patients with high grade serous ovarian carcinoma. Although the amplicon contains over 50 genes, it is notable for the presence of several members of the fibroblast growth factor signaling axis. In particular acidic fibroblast growth factor (FGF1) has been demonstrated to be one of the driving genes in mediating the observed prognostic effect of the amplicon in ovarian cancer patients. This study seeks to further validate the prognostic value of fibroblast growth receptor 4 (FGFR4), another candidate gene of the FGF/FGFR axis located in the same amplicon. The emphasis will be delineating the role the FGF1/FGFR4 signaling axis plays in high grade serous ovarian carcinoma; and test the feasibility of targeting the FGF1/FGFR4 axis therapeutically. Materials and Methods: Spearman and Pearson correlation studies on data generated from array CGH and transcriptome profiling analyses on 51 microdissected tumor samples were used to identify genes located on chromosome 5q31-35.3 that showed significant correlation between DNA and mRNA copy numbers. Significant correlation between FGF1 and FGFR4 DNA copy numbers was further validated by qPCR analysis on DNA isolated from 51 microdissected tumor samples. Immunolocalization and quantification of FGFR4 expression were performed on paraffin embedded tissue samples from 183 cases of high-grade serous ovarian carcinoma. The expression was then correlated with clinical data to assess impact on survival. The expression of FGF1 and FGFR4 in vitro was quantified by real-time PCR and western blotting in six high-grade serous ovarian carcinoma cell lines and compared to those in human ovarian surface epithelial cells to identify overexpression. The effect of FGF1 on these cell lines after serum starvation was quantified for in vitro cellular proliferation, migration/invasion, chemoresistance and survival utilizing a combination of commercially available colorimetric, fluorometric and electrical impedance assays. FGFR4 expression was then transiently silenced via siRNA transfection and the effects on response to FGF1, cellular proliferation, and migration were quantified. To identify relevant cellular pathways involved, responsive cell lines were transduced with different transcription response elements using the Cignal-Lenti reporter system and treated with FGF1 with and without transient FGFR4 knock down. This was followed by western blot confirmation for the relevant phosphoproteins. Anti-FGF1 antibodies and FGFR trap proteins were used to attempt inhibition of FGF mediated phenotypic changes and relevant signaling in vitro. Orthotopic intraperitoneal tumors were established in nude mice using serous cell lines that have been previously transfected with luciferase expressing constructs. The mice were then treated with FGFR trap protein. Tumor progression was then followed via bioluminescent imaging. The FGFR4 gene from 52 clinical samples was sequenced to screen for mutations. Results: FGFR4 DNA and mRNA copy numbers were significantly correlated and FGFR4 DNA copy number was significantly correlated with that of FGF1. Survival of patients with high FGFR4 expressing tumors was significantly shorter that those with low expression(median survival 28 vs 55 month p< 0.001) In a multivariate cox regression model FGFR expression significantly increased risk of death (HR 2.1, p<0.001). FGFR4 expression was significantly higher in all cell lines tested compared to HOSE, OVCA432 cell line in particular had very high expression suggesting amplification. FGF1 was also particularly overexpressed in OVCA432. FGF1 significantly increased cell survival after serum deprivation in all cell lines. Transient knock down of FGFR4 caused significant reduction in cell migration and proliferation in vitro and significantly decreased the proliferative effects of FGF1 in vitro. FGFR1, FGFR4 traps and anti-FGF1 antibodies did not show activity in vitro. OVCA432 transfected with the cignal lenti reporter system revealed significant activation of MAPK, NFkB and WNT pathways, western blotting confirmed the results. Reverse phase protein array (RPPA) analysis also showed activation of MAPK, AKT, WNT pathways and down regulation of E Cadherin. FGFR trap protein significantly reduced tumor growth in vivo in an orthotopic mouse model. Conclusions: Overexpression and amplification of several members of the FGF signaling axis present on the amplicon 5q31-35.3 is a negative prognostic indicator in high grade serous ovarian carcinoma and may drive poor survival associated with that amplicon. Activation of The FGF signaling pathway leads to downstream activation of MAPK, AKT, WNT and NFkB pathways leading to a more aggressive cancer phenotype with increased tumor growth, evasion of apoptosis and increased migration and invasion. Inhibition of FGF pathway in vivo via FGFR trap protein leads to significantly decreased tumor growth in an orthotopic mouse model.
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Although gastrointestinal stromal tumor (GIST) is effectively treated with imatinib, there are a number of clinical challenges in the optimal treatment of these patients. The plasma steady-state trough level of imatinib has been proposed to correlate with clinical outcome. Plasma imatinib level may be affected by a number of patient characteristics. Additionally, the ideal plasma trough concentration of imatinib is likely to vary based on the KIT genotype (genotype determines imatinib binding affinity) of the individual patient. Patients’ genotype or plasma imatinib level may influence the type and duration of response that is appreciable by clinical evaluation. The objectives of this study were to determine effects of genotype on the type of response appreciable by current imaging criteria, to determine the distribution of plasma imatinib levels in patients with GIST, to determine factors that correlate with plasma imatinib level, to determine the incremental effects of imatinib dose escalation; and to explore the median plasma levels and outcomes of patients with various KIT mutations. We therefore obtained KIT mutation information and analyzed CT response for size and density measurement of GISTs at baseline and within the first four moths of imatinib treatment. In 126 patients with metastatic/unresectable disease, the KIT genotype of patients’ tumor was significantly associated with unique response characteristics measurable by CT. Furthermore, hepatic and peritoneal metastases differed in their response characteristics. A subgroup of patients with KIT exon 9 mutation, who received higher doses of imatinib and experienced higher trough imatinib levels, experienced improved progression-free survival similar to that of KIT exon 11 patients. Therefore, we have found that imatinib plasma levels were higher in patients with elevated Aspartate amino transferase, were women, were older, or were being treated concomitantly with CYP450 substrate drugs. As expected, CYP450 inducers correlated with a lower plasma imatinib levels in GIST patients. Renal metabolism of imatinib accounts for <10%, so it was not included in the analysis but may affect covariates. Interestingly, there was a trend for low imatinib levels and inferior progression-free survival in patients who had undergone complete gastrectomy. Patients with KIT exon 9 mutation in our cohort received higher imatinib doses, experienced higher trough imatinib levels, and experienced a PFS similar to that of KIT exon 11 patients. In conclusion, imatinib plasma levels are influenced by a number of patient characteristics. The optimal imatinib plasma level for individual patients is not known but is an area of intense investigation. Our study confirms patients with KIT exon 9 mutations benefit from high-dose imatinib and higher trough imatinib levels.
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Retinoic acid is a small lipophilic molecule that exerts profound effects on the growth and differentiation of both normal and transformed cells. It is also a natural morphogen that is critical in the development of embryonic structures. The molecular effects of retinoic acid involve alterations in the expression of several proteins and these changes are presumably mediated in part by alterations in gene expression. For instance, retinoic acid causes a rapid induction of tissue transglutaminase, an enzyme involved in protein cross-linking. The molecular mechanisms responsible for the effects of retinoic acid on gene expression have not been characterized. To approach this question, I have isolated and characterized tissue transglutaminase of cDNA clones. The deduced amino acid sequences of tissue transglutaminase and of factor XIIIa showed a relatively high degree of homology in their putative calcium binding domains.^ To explore the mechanism of induction of this enzyme, both primary (macrophages) and cultured cells (Swiss 3T3-C2 and CHO fibroblasts) were used. I found that retinoic acid is a general inducer of tissue transglutaminase mRNA in these cells. In murine peritoneal macrophages retinoic acid causes a rapid accumulation of this mRNA and this effect is independent of concurrent protein synthesis. The retinoic acid effect is not mediated by a post-transcriptional increase in the stability of the tissue transglutaminase mRNA, but appears to involve an increase in the transcription rate of the tissue transglutaminase gene. This provides the first example of regulation by retinoic acid of a specific gene, supporting the hypothesis that these molecules act by directly regulating the transcriptional activity of specific genes. A molecular model for the effects of retinoic acid on the expression of genes linked to cellular proliferation and differentiation is proposed. ^
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BACKGROUND & AIMS: Refractory ascites (RA) affects 10% of patients with advanced cirrhosis and ascites. Usual therapy includes large volume paracentesis, and in selected patients, a transjugular portosystemic shunt (TIPS). These therapies may be associated with increased morbidity: paracentesis may induce circulatory dysfunction and impair quality of life and TIPS may induce encephalopathy and is associated with increased mortality in patients with severe liver dysfunction. We present the results of a multicenter, non-randomized trial to assess the safety and efficacy of a new automated pump system for treatment of RA. METHODS: Forty patients at 9 centers (February 2010-June 2011) received an implanted pump for the automated removal of ascites from the peritoneal cavity into the bladder, from where it was eliminated through normal urination. Patients were followed-up for 6months. The primary study outcome was safety. Secondary outcomes included recurrence of tense ascites and pump performance. RESULTS: Surgical complications occurred early in the study and became less frequent. The pump system removed 90% of the ascites and significantly reduced the median number of large volume paracentesis per month [3.4 (range 1-6) vs. 0.2 (range 0-4); p <0.01]. Cirrhosis-related adverse events decreased along follow-up. CONCLUSIONS: The automated pump seems an efficacious tool to move out ascites from the peritoneal cavity to the bladder. Its safety is still moderate, but a broad use in different countries will improve the surgical technique as well as the medical surveillance. A prospective randomized clinical trial vs. large volume paracentesis is underway to confirm these preliminary results.
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BACKGROUND Recent data suggest primary resection as the preferable approach in patients with signet ring cell gastric cancer (SRC). The aim of our retrospective exploratory study was to evaluate the influence of SRC on prognosis and response in esophagogastric adenocarcinoma treated with neoadjuvant chemotherapy. METHODS A total of 723 locally advanced esophagogastric adenocarcinomas (cT3/4 N any) documented in a prospective database from two academic centers were classified according to the WHO definition for SRC (more than 50 % SRC) and analyzed for their association with response and prognosis after neoadjuvant treatment. RESULTS A total of 235 tumors (32.5 %) contained SRC. Median survival of SRC was 26.3 compared with 46.6 months (p < 0.001) for non-SRC. SRC were significantly associated with female gender, gastric localization, advanced ypT and R1/2 categories, and lower risk of surgical complications and anastomotic leakage (each p < 0.001). Clinical (21.1 vs. 33.7 %, p = 0.001) and histopathological response (less than 10 % residual tumor: 16.3 vs. 28.9 %, p < 0.001) were significantly less frequent in SRC. Clinical response (p = 0.003) and complete histopathological response (pCR) (3.4 %) (p = 0.003) were associated with improved prognosis in SRC. Clinical response, surgical complications, ypTN categories, but not SRC were independent prognostic factors in forward Cox regression analysis in R0 resected patients. Risk of peritoneal carcinomatosis was increased (p < 0.001), while local (p = 0.015) and distant metastases (p = 0.02) were less frequent than in non-SRC. CONCLUSIONS Prognosis of SRC is unfavorable. Although response to neoadjuvant chemotherapy is rare in SRC, it is associated with improved outcome. Thus, chemotherapy might not generally be abandoned in SRC. A stratification based on SRC should be included in clinical trials.
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OBJECT In ventriculoperitoneal (VP) shunt surgery, laparoscopic assistance can be used for placement of the peritoneal catheter. Until now, the efficacy of laparoscopic shunt placement has been investigated only in retrospective and nonrandomized prospective studies, which have reported decreased distal shunt dysfunction rates in patients undergoing laparascopic placement compared with mini-laparotomy cohorts. In this randomized controlled trial the authors compared rates of shunt failure in patients who underwent laparoscopic surgery for peritoneal catheter placement with rates in patients who underwent traditional mini-laparotomy. METHODS One hundred twenty patients scheduled for VP shunt surgery were randomized to laparoscopic surgery or mini-laparotomy for insertion of the peritoneal catheter. The primary endpoint was the rate of overall shunt complication or failure within the first 12 months after surgery. Secondary endpoints were distal shunt failure, overall complication/ failure, duration of surgery and hospitalization, and morbidity. RESULTS The overall shunt complication/failure rate was 15% (9 of 60 cases) in the laparoscopic group and 18.3% (11 of 60 cases) in the mini-laparotomy group (p = 0.404). Patients in the laparoscopic group had no distal shunt failures; in contrast, 5 (8%) of 60 patients in the mini-laparotomy group experienced distal shunt failure (p = 0.029). Intraoperative complications occurred in 2 patients (both in the laparoscopic group), and abdominal pain led to catheter removal in 1 patient per group. Infections occurred in 1 patient in the laparoscopic group and 3 in the mini-laparotomy group. The mean durations of surgery and hospitalization were similar in the 2 groups. CONCLUSIONS While overall shunt failure rates were similar in the 2 groups, the use of laparoscopic shunt placement significantly reduced the rate of distal shunt failure compared with mini-laparotomy.
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The minimally invasive approach for hysterectomy with proven benefits and lower morbidity has become the gold standard, even in women with large uterine masses. Most women with a malignant condition present with abnormal vaginal bleeding and/or suspicious imaging such that few are diagnosed by final histopathology after surgery. However, if a malignancy is not diagnosed preoperatively, intraabdominal morcellation for uterus extraction has an increased risk for potential tumor spread and peritoneal metastases, especially in cases of unexpected leiomyosarcoma. We describe a simple method to wrap the uterus in a contained environment with a plastic bag through the posterior vaginal fornix prior to conventional coring morcellation for vaginal extraction in total laparoscopic hysterectomy. We further describe our experience with a risk stratification and treatment algorithm to implement this procedure in daily routine. A video and an illustrating sketch demonstrate the simplicity and safety of the procedure.