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The present study aimed to determine the difference in force required to puncture simulated pleura comparing Kelly clamps to fine artery forceps. The treatment of symptomatic traumatic pneumothorax and haemothorax involves puncture of the parietal pleura to allow decompression. This is usually performed using Kelly clamps or fine artery forceps. Over-puncture pulmonary injury risk increases with the force used.An experienced single operator performed puncturing of simulated parietal pleura on a thoracic mannequin while wearing a force sensor under gloves. The force imparted at the device tip onto the parietal pleura was estimated by subtracting the force required to hold the device from the total force. Outcome variables were the total maximum force and force imparted by the device.There were 11 simulated procedures completed, seven using Kelly clamps and four using fine artery forceps. After subtracting the force required to hold the chosen forceps, the median value of pleural puncture force using Kelly clamps was 52.91 N (IQR 36.68-63.56) and 10.70 N (IQR 7.64-26.56) using fine artery forceps (P = 0.006).A significantly increased force was required to puncture simulated parietal pleura using Kelly clamps compared to fine artery forceps. This higher puncture force will be associated with increased instrument acceleration at the time of pleural puncture, which may result in an increased risk of injury to the underlying lung. Based on these data, clinicians may reduce the risk of pulmonary injury by using fine artery forceps rather than Kelly clamps when performing pleural decompression.

OBJECTIVE Hypertension cure following adrenalectomy in unilateral primary aldosteronism is not guaranteed. Its likelihood is associated with pre-operative parameters, which have been variably combined in six different predictive scoring systems. The relative performance of these systems is currently unknown. The objective of this work was to identify the best performing scoring system for predicting hypertension cure following adrenalectomy for primary aldosteronism. DESIGN Retrospective analysis in a single tertiary referral centre. PATIENTS Eighty-seven adult patients with unilateral primary aldosteronism who had undergone adrenalectomy between 2004 and 2018 for whom complete data sets were available to calculate all scoring systems. MEASUREMENTS Prediction of hypertension cure by each of the six scoring systems. RESULTS Hypertension cure was achieved in 36/87 (41.4%) patients within the first post-operative year, which fell to 18/71 (25.4%) patients at final follow-up (median 53 months, P = .002). Analysis of receiver operating characteristic area under the curves for the different scoring systems identified a difference in performance at early, but not late, follow-up. For all systems, the area under the curve was lower at early compared with late follow-up and compared to performance in the cohorts in which they were originally defined. CONCLUSIONS No single scoring system performed significantly better than all others when applied in our cohort, although two did display particular advantages. It remains to be determined how best such scoring systems can be incorporated into the routine clinical care of patients with PA.

BACKGROUND The aggressive approach of vascular resection plus reconstruction in curative resection of hilar cholangiocarcinoma (HC) remains controversial. This retrospective study investigated its short- and long-term outcomes. METHODS Data of HC patients from 1989 to 2016 were reviewed. Operated patients were divided into two groups (with and without vascular resection) and compared in terms of perioperative results. Patients who had unresectable HC were also compared with patients who had been operated. RESULTS Ninety patients underwent curative HC resection. They were divided into group A (without aggressive approach, n = 68) and group B (with aggressive approach, n = 22). The groups were comparable in all parameters including rates of overall and major complication and in-hospital, 30-day and 90-day mortality except that group B had more patients with more advanced disease (P = 0.008), more patients with tumour invasion of the vasculature (40.9% versus 7.4%, P = 0.001), and fewer patients with blood transfusion (27.3% versus 52.9%, P = 0.036). The groups had similar disease-free survival (group A: median, 17.9 months, 5 years, 27.4%; group B: median, 11.7 months, 5 years, 14.3%; P = 0.427) and overall survival (group A: median, 22.0 months, 5 years, 26.5%; group B: median, 26.5 months, 5 years, 14.7%; P = 0.90). Two hundred patients with unresectable HC were compared with patients who had received operation and found to have worse survival outcomes (P

INTRODUCTION Laparoscopic hepatectomy is considered an acceptable treatment of choice in selected patients with primary hepatocellular carcinoma (HCC). Whether indocyanine green (ICG) immunofluorescence, a new technology, may improve surgery outcomes has yet to be tested. The aim of the present study was to investigate and compare the effect of ICG fluorescence imaging on the outcomes of pure laparoscopic hepatectomy and open hepatectomy for primary HCC with background cirrhosis. METHODS From January 2015 to June 2016, 20 patients with HCC and liver cirrhosis underwent laparoscopic hepatectomy with ICG immunofluorescence. The outcomes of pure laparoscopic hepatectomy with ICG immunofluorescence were compared with those of open hepatectomy. To avoid selection bias, patients were propensity score matched in a ratio of 1 : 6, with 20 patients in the laparoscopic group and 120 in the open group. RESULTS The laparoscopic group had 20 patients, and the open group had 120 patients. The laparoscopic group had less blood loss (125 vs 450 mL, P

OBJECTIVE To investigate the impact of intraoperative blood transfusion on the long-term outcomes of liver transplantation for hepatocellular carcinoma. METHOD Adult patients who had non-salvage liver transplantation at our centre between January 2005 and December 2012 for hepatocellular carcinomas that were within the University of California, San Francisco criteria and could not be resected or ablated were divided into groups with and without intraoperative blood transfusion. Comparisons were made between groups. RESULTS Ninety-nine patients were included in the study. Sixty-two (62.6%) patients received intraoperative blood transfusion. Patients without transfusion were younger (54 versus 56 years; P = 0.04) and had a lower Model for End-stage Liver Disease score (11 versus 14; P

Background Laparoscopic liver resection is associated with less perioperative blood loss, shorter hospital stay, and fewer postoperative complications in younger patients. However, it remains unclear if these short-term benefits could also be applicable to elderly patients with medical comorbidities. Aim To evaluate the perioperative outcomes of laparoscopic liver resection in patients with advanced age. Materials and Methods Patients aged ≥ 70 years old who received liver resections for malignant liver tumors between January 2002 and December 2012 were included. The perioperative outcomes of 17 patients with laparoscopic approach were matched and compared with 34 patients with conventional open approach in a 1:2 ratio. Results There was no significant difference with regard to age, gender, incidence of comorbid illness, hepatitis B positivity, and Child grading of liver function. The median tumor size was 3 cm for both groups. The types of liver resection were similar between the two groups with no significant difference in the duration of operation (laparoscopic: 195 min vs open: 210 min, P = 0.436). The perioperative blood loss was 150 mL in the laparoscopic group and 330 mL in the open group (P = 0.046) with no significant difference in the number of patients with blood transfusion. The duration of hospital stay was 6 days (3–15 days) for the laparoscopic group and 8 days (5–105 days) for the open group (P = 0.005). Conclusion Laparoscopic liver resection is safe and feasible for elderly patients. The short-term benefits of laparoscopic approach continued to be evident for geriatric oncological liver surgery.

Background & Aims High-intensity focused ultrasound (HIFU) ablation is a non-invasive treatment for unresectable hepatocellular carcinomas (HCCs), but long-term survival analysis is lacking. This study was to analyse its outcome compared to that of transarterial chemoembolization (TACE). Methods From October 2003 to September 2010, 113 patients received HIFU ablation as a treatment of HCCs at our hospital. Twenty-six patients had HCCs sized 3–8 cm. Fifty-two patients with matched tumour characteristics having TACE as primary treatment were selected for comparison. Short-term outcome and long-term survival were analysed. Results In the HIFU group (n = 26), 46 tumours were ablated. The median age of the patients was 69 (49–84) years. The median tumour size was 4.2 (3–8) cm. In the TACE group (n = 52), the median age of the patients was 67 (44–84) years. The median tumour size was 4.8 (3–8) cm. There was no hospital mortality in any of the groups. In the HIFU group, the rates of complete tumour response, partial tumour response, stable disease and progressive disease were 50%, 7.7%, 25.6% and 7.7% respectively, according to the modified Response Evaluation Criteria in Solid Tumours. The TACE group had the corresponding rates at 0%, 21.2%, 63.5% and 15.4% respectively (P

Background This study aimed to investigate whether re-resection can achieve a good survival outcome in the treatment of recurrent liver metastases of colorectal cancer. Methods Prospectively collected data of patients who underwent hepatectomy for liver tumours were reviewed. Patients whose liver tumours were metastases of colorectal cancer were included in the study provided that they had no extrahepatic metastases and received no loco-ablative treatment simultaneous with hepatectomy. Patients who did not have recurrent liver metastasis after their first liver resection (group R) and patients who underwent re-resection for recurrent liver metastasis (group RR) were compared. Results In total, 321 patients were included in the study, with 307 in group R and 14 in group RR. The two groups had comparable demographics. Insignificantly more patients in group R received major resection (55.6% versus 30.8%, P = 0.079). The median blood loss volume was 0.6 (0–12.7) L in group R and 0.35 (0–15) L in group RR (P = 0.202). Group RR had a significantly smaller median tumour size (2.5 cm versus 3.5 cm, P = 0.020) and resection margin width (0.3 cm versus 0.7 cm, P = 0.037). On univariate analysis, re-resection was not a risk factor in overall survival. On multivariate analysis, post-operative complication (hazard ratio (HR) 1.66, 95% confidence interval (CI) 1.15–2.39, P = 0.007), microscopic margin involvement (HR 1.95, 95% CI 1.26–3.04, P = 0.003) and multiple tumours (HR 1.58, 95% CI 1.17–2.14, P = 0.003) were risk factors in overall survival. The two groups had no significant differences in disease-free survival and overall survival. Conclusion Re-resection for recurrent colorectal liver metastases can achieve a favourable survival outcome at centres with expertise.

Introduction We previously conducted a randomized trial comparing the endo-laparoscopic approach (i.e. placing self-expanding metallic stents followed by laparoscopic resection) and conventional open surgery in the treatment of obstructing left-sided colon cancer. This study is a follow-up of the previous randomized trial and aims to report the long-term outcomes of the two groups. Methods Forty-eight patients from the randomized trial were followed up in an outpatient clinic with regular monitoring. Patients were compared for clinicopathological variables, disease recurrence and survival rates. Results Clinicopathological details were comparable between the two groups. During the median follow-up periods of 32 months for the open group and 65 months endo-laparoscopic group, no statistically significant difference was observed between the groups in disease recurrence rate, 5-year overall survival (27% vs 48%, P = 0.076) and 5-year disease-free survival rates (48% vs 52%, P = 0.63). Conclusion Besides being a safe bridge to subsequent elective laparoscopic surgery, preoperative self-expanding metallic stents insertion does not adversely affect oncological outcomes and patient survival. Based on our data, the endo-laparoscopic approach is the treatment of choice for patients presenting with malignant left-sided colonic obstruction.

Aim: To review the management and clinical outcomes of patients with pyogenic liver abscess in Queen Elizabeth Hospital. Methods: This is a retrospective review of the management of patients with a diagnosis of pyogenic liver abscess in Queen Elizabeth Hospital from 2000 to 2004. Results: From 2000 to 2004, 143 patients with a diagnosis of pyogenic liver abscess were managed in Queen Elizabeth Hospital. Procedure-related complications were 6/143 (4%). The success rate from percutaneous intervention was 122/143 (85%). The overall in-hospital mortality was 18/143 (13%). Mean hospital stay was 30.1 days and the median was 23 days. Multivariate logistic regression analysis on risk factors for in-hospital mortality showed high white cell count, large size abscess and prolonged activated prothrombin time as independent risk factors. Conclusion: In the present series, high white cell count, large size abscess and prolonged activated prothrombin time predicted poor outcomes in patients with pyogenic liver abscess.

We tested a variety of molecular dynamics simulation strategies in long-duration (up to several nanoseconds) constant-temperature simulations of liquid water under periodic boundary conditions. Such long durations are necessary to achieve adequate conformational sampling in simulations of membrane assemblies and other large biomolecular systems. Under a variety of circumstances, serious artifacts arise in the form of spurious collective behavior that becomes obvious only after the simulation has gone at least several hundred picoseconds. The potential energy of the system drops and the system changes from a liquid to an icy or glassy state. The underlying cause is accumulated center-of-mass motion of the system, coupled with velocity rescaling associated with constant-temperature control. The velocity rescaling in the constant-temperature algorithm reduces the thermal velocity as the net center-of-mass velocity grows, effectively causing the kinetic energy of the system to drain from thermal motions into coordinated motions. We found that the incidence and magnitude of the underlying artifactual motion leading to the spurious transition is mediated by: choice of method for computing electrostatic interactions; choice of ensemble; size of the simulation cell; SHAKE tolerance; frequency of nonbonded pairlist updating; and closeness of coupling to the temperature bath. The appearance of the spurious transition can be avoided by periodically subtracting net center-of-mass motion during the dynamics, or by improving the accuracy of the simulation by means of tightening SHAKE tolerance and updating nonbonded pairlists every timestep. © 2000 John Wiley & Sons, Inc. J Comput Chem 21: 121–131, 2000

We describe a new equilibration procedure for the atomic level simulation of a hydrated lipid bilayer. The procedure consists of alternating molecular dynamics trajectory calculations in a constant surface tension and temperature ensemble with configurational bias Monte Carlo moves to different regions of the configuration space of the bilayer, in a constant volume and temperature ensemble. The procedure is described in detail and is applied to a bilayer of 100 molecules of dipalmitoyl phosphatidylcholine (DPPC) and 3205 water molecules. We find that the hybrid simulation procedure enhances the equilibration of the bilayer as measured by the convergence of the area per molecule and the segmental order parameters, as compared with a simulation using only molecular dynamics (MD). Progress toward equilibration is almost three times as fast in CPU time, compared with a purely MD simulation. Equilibration is complete, as judged by the lack of energy drift in three separate 200-ps runs of continuous MD started from different initial states. Results of the simulation are presented and compared with experimental data and with other recent simulations of DPPC. ©1999 John Wiley & Sons, Inc. J Comput Chem 20: 1153–1164, 1999

The ionization energy (IE) for CH3SSCH3 has been measured by the pulsed molecular beam photoionization mass spectrometric method. The experimental IE of 8.18±0.03 eV is in excellent agreement with the theoretical prediction of 8.15 eV calculated using the ab initio Gaussian‐2 procedure, indicating that the experimental ionization onset can be assigned as the adiabatic IE for CH3SSCH3. The observation of the adiabatic IE(CH3SSCH3) is attributed to the low potential energy barrier for rotation about the S–S bond, which allows CH3SSCH3 to exist dynamically in a wide range of CSSC dihedral angles.

We investigate various physical consequences of theories of chiral symmetry. Predictions of the symmetry are given for the meson electroproduction process at an on-shell kinematical point where unknown contributions are minimized. Sum rules are derived for the corrections. Then we present a sum rule for the ∑ term in meson-baryon scattering from the assumptions of Bjorken limit, precocious asymptopia, and finite-mass dispersion relations. We use the commutation relations of the gluon model as input for a numerical evaluation. Next the explicit canonical structure of the light-cone restriction of the commutator of the weak current with its divergence is considered in the interacting quark-gluon model quantized in the infinite–momentum frame. The implications on neutrino scattering are analyzed. W4 and W5 are predicted to scale nontrivially as v−2F4(ω) and v−2F5(ω), which provides a simple test of light-cone current algebra feasible in the near future. The ∑ term for weak currents is deduced from a causal representation near the light-cone, and a correction is also made in the W5 – sum rule obtained by naive infinite momentum techniques. As a by-product we obtain improved derivations of the Adler neutrino sum rules.

Semi-empirical molecular orbital conformational analyses of benzocyclooctatetraene, 1, dibenzo [ a, c ] cyclooctatetraene, 2, dibenzo [ a, e ] cyclooctatetraene, 3, tribenzo[ a, c, e ] - cyclooctatetraene; 4, tetrabenzo[ a, c, e, g ] cyclooctatetraene, 5, octafluorocyclooctatetraene, 6A, and cyclooctatetraene, 6B, have been done at the MNDO and MINDO/3 (excluding 4 and 5) levels of approximation. Comparison of these results with the X-ray structural data for 1 (as determined in the present work) and the other benzannelated cyclooctatetraenes showed that, while MNDO is vastly superior to MINDO/3, both fail to account for the subtle effects of benzannelation on the conformation of the cyclooctatetraene ring. The experimental data indicate that the tub conformation of cyclooctatetraene is only slightly perturbed by the successive fusion of one and two non-adjacent benzene rings, but steric repulsion between adjacent annelated benzene rings, when present, predominates and gives rise to more folded configurations. Compound 1 crystallizes in space group P2 1 n with a = 11.856(2), b = 6.327(1), c = 12.470(3) A , β = 110.03(2)° , and Z = 4. The structure has been solved by direct methods and refined to R = 0.049 for 1435 observed Mo- K α diffractometer data.