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To undertake a meta-analysis on the value of urinary trypsinogen activation peptide (uTAP) in predicting severity of acute pancreatitis on admission.Major databases including Medline, Embase, Science Citation Index Expanded and the Cochrane Central Register of Controlled Trials in the Cochrane Library were searched to identify all relevant studies from January 1990 to January 2013. Pooled sensitivity, specificity and the diagnostic odds ratios (DORs) with 95%CI were calculated for each study and were compared to other systems/biomarkers if mentioned within the same study. Summary receiver-operating curves were conducted and the area under the curve (AUC) was evaluated.In total, six studies of uTAP with a cut-off value of 35 nmol/L were included in this meta-analysis. Overall, the pooled sensitivity and specificity of uTAP for predicting severity of acute pancreatitis, at time of admission, was 71% and 75%, respectively (AUC = 0.83, DOR = 8.67, 95%CI: 3.70-20.33). When uTAP was compared with plasma C-reactive protein, the pooled sensitivity, specificity, AUC and DOR were 0.64 vs 0.67, 0.77 vs 0.75, 0.82 vs 0.79 and 6.27 vs 6.32, respectively. Similarly, the pooled sensitivity, specificity, AUC and DOR of uTAP vs Acute Physiology and Chronic Health Evaluation II within the first 48 h of admission were found to be 0.64 vs 0.69, 0.77 vs 0.61, 0.82 vs 0.73 and 6.27 vs 4.61, respectively.uTAP has the potential to act as a stratification marker on admission for differentiating disease severity of acute pancreatitis.

AIM: To investigate the effect of preoperative biliary drainage (PBD) in jaundiced patients with hilar cholangiocarcinoma (HCCA) undergoing major liver resections. METHODS: An observational study was carried out by reviewing a prospectively maintained database of HCCA patients who underwent major liver resection for curative therapy from January 2002 to December 2012. Patients were divided into two groups based on whether PBD was performed: a drained group and an undrained group. Patient baseline characteristics, preoperative factors, perioperative and short-term postoperative outcomes were compared between the two groups. Risk factors for postoperative complications were also analyzed by logistic regression test with calculating OR and 95%CI. RESULTS: In total, 78 jaundiced patients with HCCA underwent major liver resection: 32 had PBD prior to operation while 46 did not have PBD. The two groups were comparable with respect to age, sex, body mass index and co-morbidities. Furthermore, there was no significant difference in the total bilirubin (TBIL) levels between the drained group and the undrained group at admission (294.2 ± 135.7 vs 254.0 ± 63.5, P = 0.126). PBD significantly improved liver function, reducing not only the bilirubin levels but also other liver enzymes. The preoperative TBIL level was significantly lower in the drained group as compared to the undrained group (108.1 ± 60.6 vs 265.7 ± 69.1, P = 0.000). The rate of overall postoperative complications (53.1% vs 58.7%, P = 0.626), reoperation rate (6.3% vs 6.5%, P = 1.000), postoperative hospital stay (16.5 vs 15.0, P = 0.221) and mortality (9.4% vs 4.3%, P = 0.673) were similar between the two groups. In addition, there was no significant difference in infectious complications (40.6% vs 23.9%, P = 0.116) and noninfectious complications (31.3% vs 47.8%, P = 0.143) between the two groups. Univariate and multivariate analyses revealed that preoperative TBIL > 170 μmol/L (OR = 13.690, 95%CI: 1.275-147.028, P = 0.031), Bismuth-Corlette classification (OR = 0.013, 95%CI: 0.001-0.166, P = 0.001) and extended liver resection (OR = 14.010, 95%CI: 1.130-173.646, P = 0.040) were independent risk factors for postoperative complications. CONCLUSION: Overall postoperative morbidity and mortality rates after major liver resection are not improved by PBD in HCCA patients with jaundice. Preoperative TBIL > 170 μmol/L, Bismuth-Corlette classification and extended liver resection are independent risk factors linked to postoperative complications.

AIM: To conduct a meta-analysis to compare Roux-en-Y (R-Y) gastrojejunostomy with gastroduodenal Billroth I (B-I) anastomosis after distal gastrectomy (DG) for gastric cancer. METHODS: A literature search was performed to identify studies comparing R-Y with B-I after DG for gastric cancer from January 1990 to November 2012 in Medline, Embase, Science Citation Index Expanded and the Cochrane Central Register of Controlled Trials in The Cochrane Library. Pooled odds ratios (OR) or weighted mean differences (WMD) with 95%CI were calculated using either fixed or random effects model. Operative outcomes such as operation time, intraoperative blood loss and postoperative outcomes such as anastomotic leakage and stricture, bile reflux, remnant gastritis, reflux esophagitis, dumping symptoms, delayed gastric emptying and hospital stay were the main outcomes assessed. Meta-analyses were performed using RevMan 5.0 software (Cochrane library). RESULTS: Four randomized controlled trials (RCTs) and 9 non-randomized observational clinical studies (OCS) involving 478 and 1402 patients respectively were included. Meta-analysis of RCTs revealed that R-Y reconstruction was associated with a reduced bile reflux (OR 0.04, 95%CI: 0.01, 0.14; P < 0.00 001) and remnant gastritis (OR 0.43, 95%CI: 0.28, 0.66; P = 0.0001), however needing a longer operation time (WMD 40.02, 95%CI: 13.93, 66.11; P = 0.003). Meta-analysis of OCS also revealed R-Y reconstruction had a lower incidence of bile reflux (OR 0.21, 95%CI: 0.08, 0.54; P = 0.001), remnant gastritis (OR 0.18, 95%CI: 0.11, 0.29; P < 0.00 001) and reflux esophagitis (OR 0.48, 95%CI: 0.26, 0.89; P = 0.02). However, this reconstruction method was found to be associated with a longer operation time (WMD 31.30, 95%CI: 12.99, 49.60; P = 0.0008). CONCLUSION: This systematic review point towards some clinical advantages that are rendered by R-Y compared to B-I reconstruction post DG. However there is a need for further adequately powered, well-designed RCTs comparing the same.

To conduct a meta-analysis to determine the safety and efficacy of laparoscopic liver resection (LLR) and open liver resection (OLR) for hepatocellular carcinoma (HCC).PubMed (Medline), EMBASE and Science Citation Index Expanded and Cochrane Central Register of Controlled Trials in the Cochrane Library were searched systematically to identify relevant comparative studies reporting outcomes for both LLR and OLR for HCC between January 1992 and February 2012. Two authors independently assessed the trials for inclusion and extracted the data. Meta-analysis was performed using Review Manager Version 5.0 software (The Cochrane Collaboration, Oxford, United Kingdom). Pooled odds ratios (OR) or weighted mean differences (WMD) with 95%CI were calculated using either fixed effects (Mantel-Haenszel method) or random effects models (DerSimonian and Laird method). Evaluated endpoints were operative outcomes (operation time, intraoperative blood loss, blood transfusion requirement), postoperative outcomes (liver failure, cirrhotic decompensation/ascites, bile leakage, postoperative bleeding, pulmonary complications, intraabdominal abscess, mortality, hospital stay and oncologic outcomes (positive resection margins and tumor recurrence).Fifteen eligible non-randomized studies were identified, out of which, 9 high-quality studies involving 550 patients were included, with 234 patients in the LLR group and 316 patients in the OLR group. LLR was associated with significantly lower intraoperative blood loss, based on six studies with 333 patients [WMD: -129.48 mL; 95%CI: -224.76-(-34.21) mL; P = 0.008]. Seven studies involving 416 patients were included to assess blood transfusion requirement between the two groups. The LLR group had lower blood transfusion requirement (OR: 0.49; 95%CI: 0.26-0.91; P = 0.02). While analyzing hospital stay, six studies with 333 patients were included. Patients in the LLR group were found to have shorter hospital stay [WMD: -3.19 d; 95%CI: -4.09-(-2.28) d; P0.00001] than their OLR counterpart. Seven studies including 416 patients were pooled together to estimate the odds of developing postoperative ascites in the patient groups. The LLR group appeared to have a lower incidence of postoperative ascites (OR: 0.32; 95%CI: 0.16-0.61; P = 0.0006) as compared with OLR patients. Similarly, fewer patients had liver failure in the LLR group than in the OLR group (OR: 0.15; 95%CI: 0.02-0.95; P = 0.04). However, no significant differences were found between the two approaches with regards to operation time [WMD: 4.69 min; 95%CI: -22.62-32 min; P = 0.74], bile leakage (OR: 0.55; 95%CI: 0.10-3.12; P = 0.50), postoperative bleeding (OR: 0.54; 95%CI: 0.20-1.45; P = 0.22), pulmonary complications (OR: 0.43; 95%CI: 0.18-1.04; P = 0.06), intra-abdominal abscesses (OR: 0.21; 95%CI: 0.01-4.53; P = 0.32), mortality (OR: 0.46; 95%CI: 0.14-1.51; P = 0.20), presence of positive resection margins (OR: 0.59; 95%CI: 0.21-1.62; P = 0.31) and tumor recurrence (OR: 0.95; 95%CI: 0.62-1.46; P = 0.81).LLR appears to be a safe and feasible option for resection of HCC in selected patients based on current evidence. However, further appropriately designed randomized controlled trials should be undertaken to ascertain these findings.

Underwater acoustic sensor networks (UWASNs) are playing a key role in ocean applications. Unfortunately, the efficiency of UWASNs is inferior to that of the terrestrial sensor networks (TWSNs). The main reasons are as follows: (1) UWASNs suffer long propagation delay; (2) UWASNs are limited by the narrow bandwidth. Many MAC protocols are proposed to improve the efficiency of UWASNs. However, their improvement is not enough. Moreover, few of them consider the reliability of UWASNs even though the packet loss can fail the applications. Actually, a few of the protocols employ the traditional acknowledgment (ACK) mechanism, but they suffer the throughput degradation a lot. In this paper, first, we propose a protocol called RAS, a priority scheduling approach for multihop topologies. RAS is more efficient in throughput and delay performance. Then, we propose a reliable RAS called RRAS that obtains a tradeoff between the reliability and the efficiency. RRAS designs an ACK and retransmission mechanism, that is, different from the traditional one so that it can maintain a comparable throughput when improving the reliability. Extensive evaluations are conducted to verify that RAS is efficient and RRAS is a tradeoff on reliability and efficiency.

In this report, ZnO single nanowire (NW)-based devices were fabricated on the same nanowire by e-beam lithography so that both sides had Ohmic contact and one side had Schottky contact. Information about the mechanism for low-power UV detection by these devices was unambiguously provided by I-V measurements. Adsorption and desorption of oxygen molecules at the NW surface are responsible for the UV detection by the device with Ohmic contacts on both sides. Barrier height modulations and interface states are responsible for UV detection by the device with Schottky contact on one side.

Transparency of the glass substrate plays an important role in the performance of many optical and electronic devices. Herein, the authors have demonstrated a simple method to create a high performance wide–range anti-reflection layer on a glass surface by “carving” it with a hot alkali solution (95 °C). Morphology, composition, surface and optical properties were controlled by changing both the original composition of the glass substrates and etching time. Enhanced transparency (up to 97.7%) was achieved in a wide wavelength range. Superhydrophilic and antifogging properties were also demonstrated, which provide an advantage for optical and opto-electrical devices operating outdoors, in high humidity environments or underwater. In addition, the etched glass surfaces were modified to become hydrophobic (even superhydrophobic) by n-octadecyltrichlorosilane treatment. The glass etching mechanism was investigated and verified using energy dispersive spectra (EDS) and Fourier transform infrared (FTIR) absorption spectra analyses.