Stoma associated complications after diverting loop ileostomy, end ileostomy or split stoma formation after right sided colectomy-a retrospective cohort study (StoComSplit Analysis).

BACKGROUND: For high-risk patients receiving right-sided colectomy, stoma formation is a safety strategy. Options are anastomosis with loop ileostomy, end ileostomy, or split stoma. The aim is to compare the outcome of these three options. METHODS: This retrospective cohort study included all patients who underwent right sided colectomy and stoma formation between January 2008 and December 2021 at two tertial referral centers in Switzerland. The primary outcome was the stoma associated complication rate within one year. RESULTS: A total of 116 patients were included. A total of 20 patients (17%) underwent primary anastomosis with loop ileostomy (PA group), 29 (25%) received an end ileostomy (ES group) and 67 (58%) received a split stoma (SS group). Stoma associated complication rate was 43% (n = 21) in PA and in ES group and 50% (n = 34) in SS group (n.s.). A total of 30% (n = 6) of patients in PA group needed reoperations, whereas 59% (n = 17) in ES and 58% (n = 39) in SS group had reoperations (P = 0.07). Wound infections occurred in 15% (n = 3) in PA, in 10% (n = 3) in ES, and in 30% (n = 20) in SS group (P = 0.08). A total of 13 patients (65%) in PA, 7 (24%) in ES, and 29 (43%) in SS group achieved stoma closure (P = 0.02). A total of 5 patients (38%) in PA group, 2 (15%) in ES, and 22 patients (67%) in SS group had a stoma-associated rehospitalization (P < 0.01). CONCLUSION: Primary anastomosis and loop ileostomy may be an option for selected patients. Patients with end ileostomies have fewer stoma-related readmissions than those with a split stoma, but they have a lower rate of stoma closure. CLINICAL TRIAL REGISTRATION: Trial not registered.

Perianal block with ropivacaine as a supplement to anaesthesia in proctological surgery: double-blind randomized placebo-controlled trial (PERCEPT).

BACKGROUND: The benefit of a perianal block as an adjunct to general or regional anaesthesia is debated. This RCT aimed to compare pain at 24 h and up to 14 days after proctological surgery in patients with and without a perianal block. METHODS: Between January 2018 and April 2019, patients were allocated to receive a perianal block with ropivacaine or placebo as an adjunct to anaesthesia. Patients, surgeons and assessors were blinded. The primary outcome was pain measured on a numerical rating scale (NRS) after 24 h. Secondary outcomes were need for rescue analgesia, and pain after 1, 2, 3, 6 and 12 h. The mean, rest and maximum NRS scores were measured for 14 days. RESULTS: A total of 138 patients were included, of whom 46 and 44 received general anaesthesia with or without ropivacaine respectively, and 23 and 25 received spinal anaesthesia with or without ropivacaine respectively (P = 0·858). The mean NRS score differed significantly at 24 h (mean(s.d.) 1·1(0·1) versus 2·3(0·2); P < 0·001), but not at 1 h (1·4(0·2) versus 2·2(0·3); P = 0·051). The NRS score was lower with use of ropivacaine at 2 h (1·0(0·2) versus 1·6(0·2); P = 0·045), 3 h (0·9(0·2) versus 1·5(0·2); P = 0·022), 6 h (1·1(0·2) versus 1·8(0·2); P = 0·042) and 12 h (1·2(0·2) versus 1·8(0·2); P = 0·034). The use of oral morphine equivalents was 10·2(1·4) and 16·6(2·5) mg with and without ropivacaine respectively (P = 0·028). The mean and maximum NRS scores within 14 days were lower when ropivacaine was used (95 per cent c.i. for difference 0·14 to 0·49 (P = 0·002) and 0·39 to 0·63 (P < 0·001) respectively). There was no injection-associated morbidity. CONCLUSION: Perianal block as an adjunct to general or regional anaesthesia should be recommended for proctological surgery. It yields a reduction in pain, a reduced need for opioids, and a faster recovery with minimal risk of adverse events. Registration number: NCT03405922 ( http://www.clinicaltrials.gov).

ANTECEDENTES: Se discute el beneficio del bloqueo perianal asociado a la anestesia general o regional. Este ensayo clínico aleatorizado tuvo como objetivo comparar el dolor a las 24 horas y hasta los 14 días tras cirugía proctológica en pacientes con y sin bloqueo perianal. MÉTODOS: Entre enero de 2018 y abril de 2019 se asignaron los pacientes para recibir un bloqueo perianal con ropivacaína o placebo como complemento de la anestesia. Los pacientes, los cirujanos y los evaluadores desconocían el grupo al que habían sido aleatorizados los pacientes. La variable principal fue el dolor a las 24 horas medido en una escala de numérica (numeric rating scale, NRS). Las variables secundarias fueron la necesidad de analgesia de rescate y el dolor a las 1, 2, 3, 6 y 12 horas. También se obtuvieron las puntuaciones media, en reposo y máxima de NRS durante 14 días. RESULTADOS: Se incluyeron 138 pacientes, de los que 46 recibieron anestesia general con ropivacaína, 44 anestesia general sin ropivacaína, 23 anestesia raquídea con ropivacaína y 25 anestesia raquídea sin ropivacaína (P = 0,858). La puntuación media de NRS fue significativamente diferente a las 24 horas (1,1 ± 0,1 versus 2,3 ± 0,2; P < 0,001), pero no en la primera hora (1,4 ± 0,2 versus 2,2 ± 0,3; P = 0,051). La puntuación NRS fue inferior para la ropivacaína a las 2 horas (1,0 ± 0,2 versus 1,6 ± 0,2; P = 0,045), 3 horas (0,9 ± 0,2 versus 1,5 ± 0,2; P = 0,022), 6 horas (1,1 ± 0,2 versus 1,8 ± 0,2; P = 0,042) y 12 horas (1,2 ± 0,2 versus 1,8 ± 0,2; P = 0,034). El uso equivalentes de morfina por vía oral fue de 10,2 ± 1,4 mg y 16,6 ± 2,5 mg (P = 0,028). Las puntuaciones media y máxima de NRS en los 14 días fueron más bajas para la ropivacaína (i.c. del 95%: 0,14-0,49, P = 0,002 y de 0,39-0,63, P < 0,0001, respectivamente). No hubo morbididad asociada a la inyección. CONCLUSIÓN: Se recomienda asociar el bloqueo perianal a la anestesia general o regional en la cirugía proctológica. Este procedimiento conlleva una reducción del dolor, una menor necesidad de opioides y una recuperación más rápida con efectos adversos escasos.

Left lower transverse incision versus Pfannenstiel-Kerr incision for specimen extraction in laparoscopic sigmoidectomy: a match pair analysis.

OBJECTIVE: The ideal location of specimen extraction in laparoscopic-assisted colorectal surgery is still debatable. The aim of this study was to compare the incidence of incisional hernias and surgical site infections in patients undergoing elective laparoscopic resection for recurrent sigmoid diverticulitis by performing specimen extraction through left lower transverse incision or Pfannenstiel-Kerr incision. METHODS: A total of 269 patients operated between January 2014 and December 2017 were retrospectively screened for inclusion in the study. Patients with specimen extraction through left lower transverse incision (LLT) and patients with specimen extraction through Pfannenstiel-K incision (P-K) were matched in 1:1 proportion regarding age, sex, comorbidities, and previous abdominal surgery. The incidence of incisional hernias and surgical site infections were compared by using Fisher's exact test. RESULTS: After matching 77 patients in the LLT group and 77 patients in the P-K group, they were found to be homogenous regarding the above mentioned descriptive characteristics. No patients in the P-K group developed an incisional hernia compared with 10 patients (13%) in the LLT group (p = 0.001). All these patients required hernia repair with mesh augmentation. The rate of surgical site infections was 1/77 in the P-K group and 0/77 in the LLT group (p = 1.0). In the P-K group, a wound protector was used in 86% of patients whereas in the LLT group, 39% of the wounds were protected during specimen extraction (p < 0.0001). CONCLUSION: The Pfannenstiel-Kerr incision may be the preferred extraction site compared with the left lower transverse incision given the significant reduction of the risk of incisional hernias.

Feasibility and effectiveness of laparoscopic transgastric stapler-assisted circumferential esophageal mucosectomy and simultaneous fundoplication in a pig model.

Laparoscopic transgastric stapler-assisted mucosectomy (SAM) has been described for minimally invasive circumferential en bloc resection of Barrett's esophagus (BE). Conceivably long-term disease control might be achieved by adding antireflux surgery after resection of BE by SAM. The aim of this study was to assess the feasibility of combined SAM and fundoplication in one laparoscopic procedure in six pigs. Furthermore, the competence of the gastroesophageal junction (GEJ) was assessed at baseline, after SAM, and after subsequent laparoscopic fundoplication. At each measuring point reflux measurements were repeated 6 times in each pig. Blue-colored water was infused into the stomach to provoke reflux. Intragastric yield pressure and volume were recorded until drainage of blue solution (DBS) was noted. Time to reflux was measured by DBS and by multichannel intraluminal impedance (MII). In all animals SAM followed by laparoscopic fundoplication was feasible in a single session. A weakening of the GEJ was found after SAM, indicated by decreased yield pressure (11.5 mmHg vs. 8.5 mmHg; P < 0.001), time to DBS (90 seconds vs. 60 seconds; P = 0.008) and MII (80 seconds vs. 33 seconds; P < 0.001). After additional Nissen fundoplication the GEJ competence was restored, with measurements returning to baseline values (time to DBS 99 seconds; P = 0.15; MII 76 seconds; P = 0.84). The yield pressure increased from 11.5 mmHg at baseline to 19.7 mmHg after SAM and fundoplication (P < 0.001). Laparoscopic fundoplication and SAM may be combined in a single laparoscopic session. Although the GEJ was weakened after SAM, Nissen fundoplication restored the GEJ as an effective reflux barrier in this experiment. For clinical validation, the results need to be confirmed in a prospective human trial.

Rare compound heterozygous variants in PNKP identified by whole exome sequencing in a German patient with ataxia-oculomotor apraxia 4 and pilocytic astrocytoma.

Ataxia-oculomotor apraxia type 4 (AOA4) is a rare autosomal recessive neurologic disorder. The phenotype is characterized by ataxia, oculomotor apraxia, peripheral neuropathy and dystonia. AOA4 is caused by biallelic pathogenic variants in the PNKP gene encoding a polynucleotide kinase 3'-phosphatase with an important function in DNA-damage repair. By whole exome sequencing, we identified 2 variants within the PNKP gene in a 27-year-old German woman with a clinical AOA phenotype combined with a cerebellar pilocytic astrocytoma diagnosed at 23 years of age. One variant, a duplication in exon 14 resulting in the frameshift c.1253_1269dup p.(Thr424fs*49), has previously been described as pathogenic, for example, in cases of AOA4. The second variant, representing a nonsense mutation in exon 17, c.1545C>G p.(Tyr515*), has not yet been described and is predicted to cause a loss of the 7 C-terminal amino acids. This is the first description of AOA4 in a patient with central European descent. Furthermore, the occurrence of a pilocytic astrocytoma has not been described before in an AOA4 patient. Our data demonstrate compound heterozygous PNKP germline variants in a German patient with AOA4 and provide evidence for a possible link with tumor predisposition. Localization of the 2 variants in human PNKP NP_009185.2. NM_007254.3:c.1253_1269dup p.(Thr424fs*49) is predicted to cause a frameshift within the kinase domain, NM_007254.3:c.1545C>G p.(Tyr515*) is predicted to cause loss of 2 C-terminal amino acids of the kinase domain and 5 additional C-terminal amino acids.

Surgery is essential in squamous cell cancer of the rectum.

PURPOSE: Squamous cell cancer (SCC) is a rare histological subtype of rectal cancer. It is unclear whether SCC should be treated by multimodal therapy, including surgery, or by chemoradiation alone. The objective of the study was to define an optimal treatment strategy. METHODS: Patients with rectal cancer and SCC histology were identified in the Surveillance Epidemiology and End Results Database between 1990 and 2013. According to treatment, three groups were defined: radiotherapy and surgery (RT/SX), radiotherapy (RT), and surgery (SX). Overall survival (OS) and disease-specific survival (DSS) for localized, regional, and distant disease were assessed using a multivariable Cox regression model. RESULTS: Out of 856,435 colorectal cancer patients, 1747 with SCC of the rectum were eligible. Four hundred and fifty-five were treated with RT/SX, 994 with RT, and 298 with SX. Adjusted hazard ratios (HR) did not differ for OS and DSS in localized disease. In regional disease, OS and DSS were improved for RT/SX compared to RT (HR 0.751, 95% CI 0.566-0.997, P = 0.048 and HR 0.679, 95% CI 0.478-0.966, P = 0.031). In distant disease, OS and DSS were not different. CONCLUSIONS: Multimodal therapy including surgery improved OS and DSS compared to receiving a treatment without surgery for regional disease in rectal SCC. No difference was observed in localized and distant disease. The findings contradict with recent reports favoring definitive chemoradiation.

Meta-analysis of hybrid natural-orifice transluminal endoscopic surgery versus laparoscopic surgery.

BACKGROUND: Hybrid natural-orifice transluminal endoscopic surgery (NOTES), combining access through a natural orifice with small-sized abdominal trocars, aims to reduce pain and enhance recovery. The objective of this systematic review and meta-analysis was to compare pain and morbidity in hybrid NOTES and standard laparoscopy. METHODS: A systematic literature search was performed to identify RCTs and non-RCTs comparing hybrid NOTES and standard laparoscopy. The main outcome was pain on postoperative day (POD) 1. Secondary outcomes were pain during the further postsurgical course, rescue analgesia, complications, and satisfaction with the cosmetic result. The results of meta-analysis in a random-effects model were presented as odds ratio (ORs) or standard mean differences (MDs) with 95 per cent confidence intervals. RESULTS: Six RCTs and 21 non-randomized trials including 2186 patients were identified. In hybrid NOTES the score on the numerical pain scale was lower on POD 1 (-0·75, 95 per cent c.i. -1·09 to -0·42; P = 0·001) and on POD 2-4 (-0·58, -0·91 to -0·26; P < 0·001) than that for standard laparoscopy. The need for rescue analgesia was reduced in hybrid NOTES (OR 0·36, 0·24 to 0·54; P < 0·001). The reduction in complications found for hybrid NOTES compared with standard laparoscopy (OR 0·52, 0·38 to 0·71; P < 0·001) was not significant when only RCTs were considered (OR 0·83, 0·43 to 1·60; P = 0·570). The score for cosmetic satisfaction was higher after NOTES (MD 1·14, 0·57 to 1·71; P < 0·001). CONCLUSION: Hybrid NOTES reduces postoperative pain and is associated with greater cosmetic satisfaction in selected patients.

Detailed comparison of retroviral vectors and promoter configurations for stable and high transgene expression in human induced pluripotent stem cells.

Correction of patient-specific induced pluripotent stem cells (iPSC) upon gene delivery through retroviral vectors offers new treatment perspectives for monogenetic diseases. Gene-modified iPSC clones can be screened for safe integration sites and differentiated into transplantable cells of interest. However, the current bottleneck is epigenetic vector silencing. In order to identify the most suitable retroviral expression system in iPSC, we systematically compared vectors from different retroviral genera, different promoters and their combination with ubiquitous chromatin opening elements (UCOE), and several envelope pseudotypes. Lentiviral vectors (LV) pseudotyped with vesicular stomatitis virus glycoprotein were superior to gammaretroviral and alpharetroviral vectors and other envelopes tested. The elongation factor 1α short (EFS) promoter mediated the most robust expression, whereas expression levels were lower from the potent but more silencing-prone spleen focus forming virus (SFFV) promoter. Both full-length (A2UCOE) and minimal (CBX3) UCOE juxtaposed to two physiological and one viral promoter reduced transgene silencing with equal efficiency. However, a promoter-specific decline in expression levels was not entirely prevented. Upon differentiation of transgene-positive iPSC into endothelial cells, A2UCOE.EFS and CBX3.EFS vectors maintained highest transgene expression in a larger fraction of cells as compared with all other constructs tested here. The function of UCOE diminished, but did not fully counteract, vector silencing and possibilities for improvements remain. Nevertheless, the CBX3.EFS in a LV background exhibited the most promising promoter and vector configuration for both high titer production and long-term genetic modification of human iPSC and their progeny.

[Implementation of hybrid-NOTES sigmoidectomy for diverticular disease : In a center for minimally invasive surgery]. / Implementierung der Hybrid-NOTES-Sigmoidektomie bei Divertikelkrankheit : In einem Zentrum für minimalinvasive Chirurgie.

BACKGROUND: Natural orifice transluminal endoscopic surgery (NOTES) describes surgical procedures through a natural orifice. In hybrid-NOTES small transabdominal trocars are combined with a NOTES access. OBJECTIVE: To evaluate hybrid-NOTES sigmoidectomy as a standard procedure for diverticulitis. MATERIAL AND METHODS: Elective laparoscopic sigmoidectomies performed between May 2011 and January 2016 were prospectively collated. Primary endpoint was the feasibility of hybrid-NOTES sigmoidectomy. The reasons for planning a laparoscopically-assisted sigmoidectomy (LAS), intraoperative change of treatment and reactive conversion were evaluated. Secondary endpoints were complications and operative time. RESULTS: Out of 130 laparoscopic sigmoidectomies 83% were planned for hybrid-NOTES and 8 out of 52 (15%) transvaginal (TVS) and 14 out of 56 (25%) transrectal (TRS) sigmoidectomies were intraoperatively changed to LAS. The reason for the change in 64% was that the specimen was too bulky and 80% of scheduled hybrid-NOTES procedures were carried out as planned. The operative time for TVS (146.8 ± 44.5 min) was shorter compared to LAS (173.2 ± 58.8 min, P = 0.016). The morbidities of TVS (15.3%) and TRS (14.9%) were not significantly different from LAS (23.9%, P = 0.501 and P = 0.537, respectively). CONCLUSION: Hybrid-NOTES for diverticular disease may be indicated in more than 80% of cases. In respect of intraoperative change of treatment, hybrid-NOTES is feasible in two thirds of patients. Given a high level of expertise, hybrid-NOTES can be provided as a standard procedure in sigmoidectomy for diverticular disease.

[Laparoscopic versus open rectal cancer resection: oncologically equal?]. / Laparoskopische vs. offene Rektumresektion: onkologisch gleichwertig?

The oncological equivalence of laparoscopic and open rectal cancer resection was evaluated in four multicenter randomized controlled trials. The COLOR II and the COREAN trials demonstrated oncological equivalence; however, the ACOSOG and the ALaCaRT studies came to a different conclusion. In the latter two studies a composite endpoint that assessed the quality of the mesorectal specimen, the completeness of tumor-free circumferential and distal resection margins was chosen. In both trials a higher success rate for open surgery was shown; nevertheless, the validity of this composite endpoint has not been proven and no conclusions on solid oncological endpoints can be drawn. The COLOR II and the COREAN trial therefore remain the only available studies which investigated solid oncological endpoints, such as local recurrence and disease-free survival over an adequate follow-up time period of 3 years; however, the comparability of the study groups at least of the COLOR II trial needs to be called into question as only the experience of the laparoscopic surgeons was assessed. With a local recurrence rate of 5 % in both groups the oncological quality seems nevertheless to be good; therefore, a systematically inadequate control group should not be assumed. At this point it can be concluded that a good oncological outcome can be achieved with laparoscopic rectal resection in the hands of experts. For a final assessment the long-term results of the on-going trials needs to be awaited. If the promising results for laparoscopic surgery of the COLOR II trial are confirmed laparoscopic rectal resection should be preferred to open resection in the future. This conclusion is based on the generally known perioperative benefits of minimally invasive surgery.

Hartmann's procedure and laparoscopic reversal versus primary anastomosis and ileostomy closure for left colonic perforation.

PURPOSE: Emergency surgical strategies for acute left-sided colonic perforation are evolving preferring primary anastomosis (PA) with ileostomy to Hartmann's procedure (HP) based on the morbidity and reversal rates. However, HP is still commonly performed. Hartmann's reversal is associated with considerable morbidity. It is of interest whether laparoscopic reversal results in a lower morbidity as retrospective data suggest. Here, we compared the combined morbidity rates for two surgical strategies: strategy A, HP followed by laparoscopic reversal, and strategy B, sigmoid resection with PA followed by ileostomy closure. METHODS: Prospectively collected data of all consecutive patients undergoing HP for benign left-sided colonic perforation between 2010 and 2014 were retrospectively compared to data of patients undergoing PA. Groups were matched for age and Charlson comorbidity index. Additionally, patients were analyzed for American Society of Anesthesiologists score, body mass index, and peritonitis stage. End points were morbidity, operation time, reversal rate, time to reversal, and length of hospital stay. RESULTS: The study included 32 patients for whom Hartmann's reversal was planned, along with 32 matched patients who underwent PA and diverting ileostomy. Median age was 75 and 72 years, Charlson score was 6 (4-9) and 6 (5-7), and patients classified by the American Society of Anesthesiologists (ASA) higher than III were 81 % in both groups. Combined major morbidity rates were 21 % for strategy A and 20 % for strategy B (p = 1.0). Combined comprehensive complication index was 16.4 ± 14.1 and 12.3 ± 19.1 (p = 0.08). HP reversal by laparoscopy was achieved in 71 %. The colostomy reversal rate was 75 % compared to ileostomy closure rate of 88 % (p = 0.34). CONCLUSIONS: Laparoscopic Hartmann's reversal is achievable in a high proportion of patients. Strategy B tends to have lower overall morbidity; meanwhile, major morbidity seems to be similar. Yet, in critically ill patients and in the absence of expertise of the surgeon on call, HP followed by elective laparoscopic reversal represents a viable alternative.

Hyperactivation of mTORC1 and mTORC2 by multiple oncogenic events causes addiction to eIF4E-dependent mRNA translation in T-cell leukemia.

High activation of the PI3K-AKT-mTOR pathway is characteristic for T-cell acute lymphoblastic leukemia (T-ALL). The activity of the master regulator of this pathway, PTEN, is often impaired in T-ALL. However, experimental evidence suggests that input from receptor tyrosine kinases (RTKs) is required for sustained mTOR activation, even in the absence of PTEN. We previously reported the expression of Neurotrophin receptor tyrosine kinases (TRKs) and their respective ligands in primary human leukemia samples. In the present study we aimed to dissect the downstream signaling cascades of TRK-induced T-ALL in a murine model and show that T-ALLs induced by deregulated receptor tyrosine kinase signaling acquire activating mutations in Notch1 and lose PTEN during clonal evolution. Some clones additionally lost one allele of the homeodomain transcription factor Cux1. All events independently led to a gradual hyperactivation of both mTORC1 and mTORC2 signaling. We dissected the role of the individual mTOR complexes by shRNA knockdown and found that the separate depletion of mTORC1 or mTORC2 reduced the growth of T-ALL blasts, but was not sufficient to induce apoptosis. In contrast, knockdown of the mTOR downstream effector eIF4E caused a striking cytotoxic effect, demonstrating a critical addiction to cap-dependent mRNA-translation. Although high mTORC2-AKT activation is commonly associated with drug-resistance, we demonstrate that T-ALL displaying a strong mTORC2-AKT activation were specifically susceptible to 4EGI-1, an inhibitor of the eIF4E-eIF4G interaction. To decipher the mechanism of 4EGI-1, we performed a genome-wide analysis of mRNAs that are translationally regulated by 4EGI-1 in T-ALL. 4EGI-1 effectively reduced the ribosomal occupancy of mRNAs that were strongly upregulated in T-ALL blasts compared with normal thymocytes including transcripts important for translation, mitochondria and cell cycle progression, such as cyclins and ribosomal proteins. These data suggest that disrupting the eIF4E-eIF4G interaction constitutes a promising therapy strategy in mTOR-deregulated T-cell leukemia.

Improved retroviral episome transfer of transcription factors enables sustained cell fate modification.

Retroviral vectors are versatile gene transfer vehicles widely used in basic research and gene therapy. Mutation of retroviral integrase converts these vectors into transient, integration-deficient gene delivery vehicles associated with a high degree of biosafety. We explored the option to use integration-deficient retroviral vectors to achieve transient ectopic expression of transcription factors, which is considered an important tool for induced cell fate conversion. Stepwise optimization of the retroviral episome transfer as exemplified for the transcription factor Oct4 enabled to improve both expression magnitude and endurance. Long terminal repeat-driven γ-retroviral vectors were identified as the most suitable vector architecture. Episomal expression was enhanced by epigenetic modifiers, and Oct4 activity was increased following fusion to a minimal transactivation motif of herpes simplex virus VP16. Based on kinetic analyses, we identified optimal time intervals for repeated vector administration and established prolonged expression windows of choice. Providing proof-of-concept, episomal transfer of Oct4 was potent to mediate conversion of human fibroblasts stably expressing Klf4, Sox2 and c-Myc into induced pluripotent stem cells, which were mainly free of residual Oct4 vector integration. This study provides evidence for suitability of retroviral episome transfer of transcription factors for cell fate conversion, allowing the generation of distinct patient- or disease-specific cell types.

A 'telomere-associated secretory phenotype' cooperates with BCR-ABL to drive malignant proliferation of leukemic cells.

Telomere biology is frequently associated with disease evolution in human cancer and dysfunctional telomeres have been demonstrated to contribute to genetic instability. In BCR-ABL(+) chronic myeloid leukemia (CML), accelerated telomere shortening has been shown to correlate with leukemia progression, risk score and response to treatment. Here, we demonstrate that proliferation of murine CML-like bone marrow cells strongly depends on telomere maintenance. CML-like cells of telomerase knockout mice with critically short telomeres (CML-iG4) are growth retarded and proliferation is terminally stalled by a robust senescent cell cycle arrest. In sharp contrast, CML-like cells with pre-shortened, but not critically short telomere lengths (CML-G2) grew most rapidly and were found to express a specific 'telomere-associated secretory phenotype', comprising secretion of chemokines, interleukins and other growth factors, thereby potentiating oncogene-driven growth. Moreover, conditioned supernatant of CML-G2 cells markedly enhanced proliferation of CML-WT and pre-senescent CML-iG4 cells. Strikingly, a similar inflammatory mRNA expression pattern was found with disease progression from chronic phase to accelerated phase in CML patients. These findings demonstrate that telomere-induced senescence needs to be bypassed by leukemic cells in order to progress to blast crisis and provide a novel mechanism by which telomere shortening may contribute to disease evolution in CML.

Suture repair of umbilical hernia during caesarean section: a case-control study.

PURPOSE: The objective of this study was to investigate the additional burdens in terms of pain, prolongation of surgery and morbidity which is added to elective caesarean section if umbilical hernia suture repair is performed simultaneously. Secondly, patient's satisfaction and hernia recurrence rate were assessed. METHODS: Consecutive women with symptomatic umbilical hernia undergoing internal or external suture repair during elective caesarean were included in this retrospective cohort-control study. Data on post-operative pain, duration of surgery and morbidity of a combined procedure were collected. These patients were matched 1:10 to women undergoing caesarean section only. Additionally, two subgroups were assessed separately: external and internal suture hernia repair. These subgroups were compared for patient's satisfaction, cosmesis, body image and recurrence rate. RESULTS: Fourteen patients with a mean age of 37 years were analysed. Internal suture repair (n = 7) prolonged caesarean section by 20 min (p = 0.001) and external suture repair (n = 7) by 34 min (p < 0.0001). Suture repair did not increase morphine use (0.38 ± 0.2 vs. 0.4 ± 02 mg/kg body weight), had no procedure-related morbidity and prolonged hospitalization by 0.5 days (p = 0.01). At a median follow-up of 37 (5-125) months, two recurrences in each surgical technique, internal and external suture repair, occurred (28 %). Body image and cosmesis score showed a higher level of functioning in internal suture repair (p = 0.02; p = 0.04). DISCUSSION: Despite a high recurrence rate, internal suture repair of a symptomatic umbilical hernia during elective caesarean section should be offered to women if requested. No additional morbidity or scar is added to caesarean section. Internal repair is faster, and cosmetic results are better, additional skin or fascia dissection is avoided, and it seems to be as effective as an external approach. Yet, women must be informed on the high recurrence rate.

Recruitment of the tumour suppressor protein p73 by Kaposi's Sarcoma Herpesvirus latent nuclear antigen contributes to the survival of primary effusion lymphoma cells.

Kaposi's Sarcoma Herpesvirus (KSHV) is the causative agent of Kaposi's Sarcoma (KS) and two rare lymphoproliferative disorders, primary effusion lymphoma (PEL) and the plasmablastic variant of multicentric Castleman's disease (MCD). The KSHV latency-associated nuclear antigen-1 (LANA), required for the replication and maintenance of latent viral episomal DNA, is involved in the transcriptional regulation of viral and cellular genes and interacts with different cellular proteins, including the tumour suppressor p53. Here, we report that LANA also recruits the p53-related nuclear transcription factor p73, which influences cellular processes like DNA damage response, cell cycle progression and apoptosis. Both the full-length isoform TAp73α, as well as its dominant negative regulator ΔNp73α, interact with LANA. LANA affects TAp73α stability and sub-nuclear localisation, as well as TAp73α-mediated transcriptional activation of target genes. We observed that the small-molecule inhibitor Nutlin-3, which disrupts the interaction of p53 and p73 with MDM2, induces apoptotic cell death in p53 wild-type, as well as p53-mutant PEL cell lines, suggesting a possible involvement of p73. The small-molecule RETRA, which activates p73 in the context of mutant p53, leads to the induction of apoptosis in p53-mutant PEL cell lines. RNAi-mediated knockdown of p73 confirmed that these effects depend on the presence of the p73 protein. Furthermore, both Nutlin-3 and RETRA disrupt the LANA-p73 interaction in different PEL cell lines. These results suggest that LANA modulates p73 function and that the LANA-p73 interaction may represent a therapeutic target to interfere with the survival of latently KSHV-infected cells.

Parastomal hernia incarceration due to migrated intragastric balloon.

The temporary placement of intragastric balloons is a common method to achieve rapid weight loss before planned metabolic surgery. We report the case of a 48-year-old morbidly obese patient. Ten years ago the patient underwent emergency sigmoidectomy with creation of a double-barreled ileostomy for perforated diverticulitis. Over time he developed a giant parastomal hernia. For preoperative weight reduction before planned restoration of intestinal continuity, an intragastric balloon was inserted 3 years ago. The patient was admitted to our emergency department with peritonism and a septic shock. After computed tomography showing small bowel ileus, laparotomy was performed, revealing marked ischemia of incarcerated small and large intestine. Only postoperatively was the intragastric balloon found in the resected small bowel, causing a mechanical ileus with consecutive incarceration of the bowel. We review the literature on complications due to the migration of intragastric balloons. This clinical case gives a fair warning of the possible deleterious outcome of intragastric balloons, especially in hernia patients.

Activation of Evi1 inhibits cell cycle progression and differentiation of hematopoietic progenitor cells.

The transcription factor Evi1 has an outstanding role in the formation and transformation of hematopoietic cells. Its activation by chromosomal rearrangement induces a myelodysplastic syndrome with progression to acute myeloid leukemia of poor prognosis. Similarly, retroviral insertion-mediated upregulation confers a competitive advantage to transplanted hematopoietic cells, triggering clonal dominance or even leukemia. To study the molecular and functional response of primary murine hematopoietic progenitor cells to the activation of Evi1, we established an inducible lentiviral expression system. EVI1 had a biphasic effect with initial growth inhibition and retarded myeloid differentiation linked to enhanced survival of myeloblasts in long-term cultures. Gene expression microarray analysis revealed that within 24 h EVI1 upregulated 'stemness' genes characteristic for long-term hematopoietic stem cells (Aldh1a1, Abca1, Cdkn1b, Cdkn1c, Epcam, among others) but downregulated genes involved in DNA replication (Cyclins and their kinases, among others) and DNA repair (including Brca1, Brca2, Rad51). Cell cycle analysis demonstrated EVI1's anti-proliferative effect to be strictly dose-dependent with accumulation of cells in G0/G1, but preservation of a small fraction of long-term proliferating cells. Although confined to cultured cells, our study contributes to new hypotheses addressing the mechanisms and molecular targets involved in preleukemic clonal dominance or leukemic transformation by Evi1.