Quantum Critical Behavior of Entanglement in Lattice Bosons with Cavity-Mediated Long-Range Interactions.

We analyze the ground-state entanglement entropy of the extended Bose-Hubbard model with infinite-range interactions. This model describes the low-energy dynamics of ultracold bosons tightly bound to an optical lattice and dispersively coupled to a cavity mode. The competition between on-site repulsion and global cavity-induced interactions leads to a rich phase diagram, which exhibits superfluid, supersolid, and insulating (Mott and checkerboard) phases. We use a slave-boson treatment of harmonic quantum fluctuations around the mean-field solution and calculate the entanglement entropy across the phase transitions. At commensurate filling, the insulator-superfluid transition is signaled by a singularity in the area-law scaling coefficient of the entanglement entropy, which is similar to the one reported for the standard Bose-Hubbard model. Remarkably, at the continuous Z_{2} superfluid-to-supersolid transition we find a critical logarithmic term, regardless of the filling. This behavior originates from the appearance of a roton mode in the excitation and entanglement spectrum, becoming gapless at the critical point, and it is characteristic of collective models.

Intraoperative identification and analysis of lymph nodes at laparoscopic colorectal cancer surgery using fluorescence imaging combined with rapid OSNA pathological assessment.

BACKGROUND: Standard surgical practice for colorectal cancer involves resection of the primary lesion and all draining lymph nodes. Accurate intraoperative assessment of nodal status could allow stratified resectional extent. One-step nucleic acid (OSNA) can provide a rapid method of interrogating nodal tissue, whilst near-infrared (NIR) laparoscopy together with indocyanine green (ICG) can identify relevant nodal tissue intraoperatively. METHODS: ICG was administered around the tumour endoscopically prior to the operation. Fluorescent nodes identified by NIR were marked and submitted for whole-node OSNA analysis. Further fresh lymph nodes dissected from the standard resection specimen were examined and analysed by both conventional histology and OSNA. In addition, the status of the fluorescent nodes was compared to that of non-ICG nodes to assess their predictive value. RESULTS: Sixteen patients were recruited with a total final lymph node count of 287. 78 fresh lymph nodes were identified on fresh dissection for both histological and OSNA assessment with an analytical concordance rate of 98.7% (77/78). OSNA sensitivity was 1 (0.81-1, 95% CI) and specificity 0.98 (0.91-1, 95% CI). Six patients had a total of nine nodes identified intraoperatively by ICG fluorescence. Of these nine nodes, one was positive for metastasis on OSNA. OSNA analysis of the ICG-labelled node matched the final histological nodal stage in 3/6 patients (two being N0 and one N1). The final pathological nodal stage of the other three was N1 or N2, while the ICG nodes were negative. CONCLUSION: OSNA is highly concordant with standard histology, although only a minority of nodes identifiable by full pathological analysis were found for OSNA on fresh dissection. OSNA can be combined with NIR and ICG lymphatic mapping to provide intraoperative assessment of nodal tissue in patients with colorectal cancer.

Peliosis lienalis with atraumatic splenic rupture in a patient with chronic myelomonocytic leukemia: A case report.

INTRODUCTION: Atraumatic splenic rupture is a rare but life-threatening condition which may be associated with hematological malignancies. PRESENTATION OF CASE: We present the case of a 63-year-old male patient with a history of chronic myelomonocytic leukemia and sarcoidosis under therapy with prednisone, who suffered an atraumatic splenic rupture with hemodynamic instability. He was managed with proximal splenic artery embolization and secondary open splenectomy. On pathology the diagnosis of peliosis lienalis was established. DISCUSSION: Peliosis is a rare pathological entity, which presents with multiple blood-filled cavities within parenchymatous organs and is of unknown etiology and pathogenesis. In retrospect a rapid increase in splenomegaly and inhomogeneous parenchyma of the spleen on sonography was realized. CONCLUSION: Sonographic changes in size and parenchyma of the spleen in patients with hematological malignancies might help suspecting peliosis lienalis with impending splenic rupture and could alter clinical management towards a prophylactic splenectomy.

The association of surgical drains with surgical site infections - A prospective observational study.

BACKGROUND: Surgical drains are widely used despite limited evidence in their favor. This study describes the associations between drains and surgical site infections (SSI). METHODS: This prospective observational double center study was performed in Switzerland between February 2013 and August 2015. RESULTS: The odds of SSI in the presence of drains were increased in general (OR 2.41, 95%CI 1.32-4.30, p = 0.004), but less in vascular and not in orthopedic trauma surgery. In addition to the surgical division, the association between drains and SSI depended significantly on the duration of surgery (p = 0.01) and wound class (p = 0.034). Furthermore, the duration of drainage (OR 1.24, 95%CI 1.15-1.35, p < 0.001), the number (OR 1.74, 95%CI 1.09-2.74, p = 0.019) and type of drains (open versus closed: OR 3.68, 95%CI 1.88, 6.89, p < 0.001) as well as their location (overall p = 0.002) were significantly associated with SSI. CONCLUSIONS: The general use of drains is discouraged. However, drains may be beneficial in specific surgical procedures.

Linear Mixed Effects Analysis Reveals the Significant Impact of Preoperative Diet Success on Postoperative Weight Loss in Gastric Bypass Surgery.

BACKGROUND: Several studies investigated the impact of preoperative weight loss on bariatric surgery outcome. However, they mostly focus on small groups of patients or lack updated statistical support. METHODS: Two hundred and thirty-nine consecutive patients undergoing laparoscopic, proximal Roux-en-Y gastric bypass at our institution between September 2009 and November 2015 were studied. Patients were operated by the same surgeon, applying a standardized technique and followed a 500-kcal/day preoperative diet, starting 14 days before surgery. Body weight was measured before diet, at surgery, and at least three times postoperatively. A linear mixed effects (LME) model and Benedict and Harris formula were used to assess association of pre- and postoperative weight loss up to 2 years postoperatively. RESULTS: Patients' (184 females) initial weight was 121.7 kg (females 117.2 kg; males 136.6 kg). They lost on average 5.3 kg (females 4.7 kg; males 7.0 kg) pre- and 36.8 kg (females 36.7 kg; males 37.0 kg) postoperatively, within 2 years. Average excess weight loss (EWL) was 67.2% (females 66.6%; males 67.4%). In 205 patients (154 females), EWL exceeded 50%. Longitudinal data analysis according to LME showed a significant impact of pre- on postoperative weight loss (p < 0.001, likelihood-ratio test, LRT). These effects were undetectable if patients were evaluated by non-parametric analysis based on application of the Benedict and Harris formula. CONCLUSIONS: Preoperative dietary success is associated with postoperative weight loss. Effects predicted by the LME model are most pronounced in the first 4-6 months after surgery and are fading away within 24 months postoperatively. External factors not considered in this study might dominate in later phases.

The Acute Physiology and Chronic Health Evaluation II score is helpful in predicting the need of relaparotomies in patients with secondary peritonitis of colorectal origin.

BACKGROUND: Secondary peritonitis of colorectal origin has considerable morbidity and mortality. Relaparotomies are frequently necessary in the course of the disease. The objective of this study was to evaluate several scores in terms of their predictive value, i.e. whether Mannheim Peritonitis Index (MPI), Acute Physiology And Chronic Health Evaluation (APACHE) II, or Colorectal Physiological and Operative Severity Score for the Enumeration of Mortality and Morbidity (CR-POSSUM) scores can predict relaparotomies. METHODS: Charts of 147 patients treated for secondary peritonitis of colorectal origin were retrospectively reviewed, MPI, APACHE II, and CR-POSSUM scores were calculated, and groups of patients with or without relaparotomies were compared. RESULTS: Thirty-four percent of patients underwent one or more relaparotomies. Patients with relaparotomies showed a significantly higher APACHE II score than patients without relaparotomies (p = 0.004). MPI (p = 0.072) and CR-POSSUM score (p = 0.319) did not differ between the two groups. A high APACHE II score was also significantly associated with the need for a relaparotomy on demand (p <0.001), and for the combined outcome parameter relaparotomy and/or an interventional drainage (p = 0.046). Both other scores were not predictive for these outcomes. Overall in-hospital mortality was 21.8%. All three scores investigated were predictive for mortality. Sensitivity was 62.5%, 78.1%, and 75.0% for MPI, APACHE II score, and CR-POSSUM score, respectively. CONCLUSION: The Acute Physiology And Chronic Health Evaluation II score might be helpful in predicting the need for relaparotomies in patients with secondary peritonitis of colorectal origin.