bluuebunny/crossref_metadata_2025_split huggingface dataset:
National risk prediction model for perioperative mortality in non-cardiac surgery
Authors: Campbell D , Boyle L , Soakell-Ho M , Hider P , Wilson L , Koea J , Merry A F , Frampton C , Short T G 
Published: August 2019

Abstract

Background
Many multivariable models to calculate mortality risk after surgery are limited by insufficient sample size at development or by application to cohorts distinct from derivation populations. The aims of this study were to validate the Surgical Outcome Risk Tool (SORT) for a New Zealand population and to develop an extended NZRISK model to calculate 1-month, 1-year and 2-year mortality after non-cardiac surgery.

Methods
Data from the New Zealand National Minimum Data Set for patients having surgery between January 2013 and December 2014 were used to validate SORT. A random 75 per cent split of the data was used to develop the NZRISK model, which was validated in the other 25 per cent of the data set.

Results
External validation of SORT in the 360 140 patients who underwent surgery in the study period showed good discrimination (area under the receiver operating characteristic curve (AUROC) value of 0·906) but poor calibration (McFadden's pseudo-R2 0·137, calibration slope 5·32), indicating it was invalid in this national surgical population. Internal validation of the NZRISK model, which incorporates sex and ethnicity in addition to the variables used in SORT for 1-month, 1-year and 2-year outcomes, demonstrated excellent discrimination with AUROC values of 0·921, 0·904 and 0·895 respectively, and excellent calibration (McFadden's pseudo-R2 0·275, 0·308 and 0·312 respectively). Calibration slopes were 1·12, 1·02 and 1·02 respectively.

Conclusion
The SORT performed poorly in this national population. However, inclusion of sex and ethnicity in the NZRISK model improved performance. Calculation of mortality risk beyond 30 days after surgery adds to the utility of this tool for shared decision-making.
Meta-analysis of the association between primary tumour location and prognosis after surgical resection of colorectal liver metastases
Authors: Wang X-Y , Zhang R , Wang Z , Geng Y , Lin J , Ma K , Zuo J-L , Lu L , Zhang J-B , Zhu W-W , Chen J-H 
Published: August 2019

Abstract

Background
Primary tumour location is emerging as an important prognostic factor in localized and metastatic colorectal cancers. However, its prognostic role in colorectal liver metastasis (CRLM) after hepatectomy remains controversial. A systematic review and meta-analysis was undertaken to evaluate its prognostic value.

Methods
References were identified through searches of PubMed, Embase, Web of Science and the Cochrane Library comparing overall or disease-free survival after hepatic resection between patients with CRLM originating from right- or left-sided colorectal cancers. Data were pooled using hazard ratios (HRs) and 95 per cent confidence intervals according to a random-effects model. Meta-regression and subgroup analyses were conducted to assess the effect of underlying confounding factors on HR estimates and to adjust for this.

Results
The final analysis included 21 953 patients from 45 study cohorts. Compared with left-sided primary tumour location, right-sided location was associated with worse overall survival (HR 1·39, 95 per cent c.i. 1·28 to 1·51; P &lt; 0·001; prediction interval 1·00 to 1·93), and also tended to have a negative impact on disease-free survival (HR 1·18, 1·06 to 1·32; P = 0·004; prediction interval 0·79 to 1·75). Subgroup analysis showed that the negative effect of right-sided primary tumour location on overall survival was more prominent in the non-Asian population (HR 1·47, 1·33 to 1·62) than the Asian population (HR 1·18, 1·05 to 1·32) (P for interaction &lt;0·01).

Conclusion
This study demonstrated a prognostic role for primary tumour location in patients with CRLM receiving hepatectomy, especially regarding overall survival. Adding primary tumour location may provide important optimization of prognosis prediction models for CRLM in current use.
Nationwide study of appendicitis in children
Authors: Omling E , Salö M , Saluja S , Bergbrant S , Olsson L , Persson A , Björk J , Hagander L 
Published: August 2019

Abstract

Background
Paediatric surgical care is increasingly being centralized away from low-volume centres, and prehospital delay is considered a risk factor for more complicated appendicitis. The aim of this study was to determine the incidence of paediatric appendicitis in Sweden, and to assess whether distance to the hospital was a risk factor for complicated disease.

Methods
A nationwide cohort study of all paediatric appendicitis cases in Sweden, 2001–2014, was undertaken, including incidence of disease in different population strata, with trends over time. The risk of complicated disease was determined by regression methods, with travel time as the primary exposure and individual-level socioeconomic determinants as independent variables.

Results
Some 38 939 children with appendicitis were identified. Of these, 16·8 per cent had complicated disease, and the estimated risk of paediatric appendicitis by age 18 years was 2·5 per cent. Travel time to the treating hospital was not associated with complicated disease (adjusted odds ratio (OR) 1·00 (95 per cent c.i. 0·96 to 1·05) per 30-min increase; P = 0·934). Level of education (P = 0·177) and family income (P = 0·120) were not independently associated with increased risk of complicated disease. Parental unemployment (adjusted OR 1·17, 95 per cent c.i. 1·05 to 1·32; P = 0·006) and having parents born outside Sweden (1 parent born in Sweden: adjusted OR 1·12, 1·01 to 1·25; both parents born outside Sweden: adjusted OR 1·32, 1·18 to 1·47; P &lt; 0·001) were associated with an increased risk of complicated appendicitis.

Conclusion
Every sixth child diagnosed with appendicitis in Sweden has a more complicated course of disease. Geographical distance to the surgical facility was not a risk factor for complicated appendicitis.
Population-based study of the effect of preoperative breast MRI on the surgical management of ductal carcinoma in situ
Authors: Keymeulen K B I M , Geurts S M E , Lobbes M B I , Heuts E M , Duijm L E M , Kooreman L F S , Voogd A C , Tjan-Heijnen V C G 
Published: August 2019

Abstract

Background
Determinants of the use of breast MRI in patients with ductal carcinoma in situ (DCIS) in the Netherlands were studied, and whether using MRI influenced the rates of positive resection margins and mastectomies.

Methods
All women aged less than 75 years, and diagnosed with DCIS between 2011 and 2015, were identified from the Netherlands Cancer Registry. Multivariable logistic regression analyses were performed, adjusting for incidence year, age, hospital type, DCIS grade and multifocality.

Results
Breast MRI was performed in 2382 of 10 415 DCIS cases (22·9 per cent). In multivariable analysis, patients aged less than 50 years, those with high- or intermediate-grade DCIS and patients with multifocal disease were significantly more likely to have preoperative MRI. Patients undergoing MRI were more likely to have a mastectomy, either as first surgical treatment or following breast-conserving surgery (BCS) in the event of positive margins (odds ratio (OR) 2·11, 95 per cent c.i. 1·91 to 2·33). The risk of positive surgical margins after BCS was similar for those with versus without MRI. The secondary mastectomy rate after BCS was higher in patients who had MRI, especially in women aged less than 50 years (OR 1·94, 1·31 to 2·89). All findings were similar for low- and intermediate/high-grade DCIS.

Conclusion
Adding MRI to conventional breast imaging did not improve surgical outcome in patients diagnosed with primary DCIS. The likelihood of undergoing a mastectomy was twice as high in the MRI group, and no reduction in the risk of margin involvement was observed after BCS.
Germline mismatch repair gene variants analyzed by universal sequencing in Japanese cancer patients
Authors: Kiyozumi Yoshimi , Matsubayashi Hiroyuki , Horiuchi Yasue , Higashigawa Satomi , Oishi Takuma , Abe Masato , Ohnami Sumiko , Urakami Kenichi , Nagashima Takeshi , Kusuhara Masatoshi , Miyake Hidehiko , Yamaguchi Ken 
Published: August 2019

AbstractBackgroundLynch syndrome (LS) is the commonest inherited cancer syndrome caused by pathogenic variants of germline DNA mismatch repair (g.MMR) genes. Genome‐wide sequencing is now increasingly applied for tumor characterization, but not for g.MMR. The aim of this study was to evaluate the incidence and pathogenicity of g.MMR variants in Japanese cancer patients.MethodsFour g.MMR genes (MLH1, MSH2, MSH6, and PMS2) were analyzed by next generation sequencing in 1058 cancer patients (614 male, 444 female; mean age 65.6 years) without past diagnosis of LS. The g.MMR variant pathogenicity was classified based on the ClinVar 2015 database. Tumor MMR immunohistochemistry, microsatellite instability (MSI), and BRAF sequencing were also investigated in specific cases.ResultsOverall, 46 g.MMR variants were detected in 167 (15.8%) patients, 17 likely benign variants in 119 patients, 24 variants of uncertain significance (VUSs) in 68 patients, two likely pathogenic variants in two patients, and three pathogenic variants in three (0.3%) patients. The three pathogenic variants included two colorectal cancers with MLH1 loss and high MSI and one endometrial cancer with MSH6 loss and microsatellite stability. Two likely pathogenic variants were shifted to VUSs by ClinVar (2018). One colon cancer with a likely benign variant demonstrated MLH1 loss and BRAF mutation, but other nonpathogenic variants showed sustained MMR and microsatellite stability.ConclusionsUniversal sequencing of g.MMR genes demonstrated sundry benign variants, but only a small proportion of cancer patients had pathogenic variants. Pathogenicity evaluation using the ClinVar database agreed with MSI, MMR immunohistochemistry, and BRAF sequencing.
Prolonged postoperative ileus in gastric surgery: Is there any difference between laparoscopic and open surgery?
Authors: Liang Wenquan , Li Jiyang , Zhang Wang , Liu Jie , Li Mingsen , Gao Yunhe , Wang Ning , Cui Jianxin , Zhang Kecheng , Xi Hongqing , Wei Bo , Chen Lin 
Published: August 2019

AbstractBackgroundProlonged postoperative ileus (PPOI) is a common complication after abdominal surgery, but data about risk factors of PPOI for patients with gastric cancer are rare. We sought to investigate the impact of laparoscopic versus open surgery for PPOI after gastric cancer surgery.MethodsA retrospective cohort study was conducted using a registry database consecutively collected from June 2016 to March 2017. PPOI was defined as no bowel function persisting for more than 4 days. Univariate analysis and multiple logistic regression models were performed to investigate risk factors, and stratified analysis was carried out to examine the primary association at different levels of a potential confounding factor.ResultsA total of 162 patients composed of 63 patients undergoing laparotomy and 99 patients undergoing laparoscopy were enrolled and PPOI was observed in 32 (19.75%) patients. Risk factors significantly correlated with PPOI were as follows: open surgery, older age, late surgical pathologic staging, postoperative use of opioid analgesic, low level of postoperative albumin and serum potassium. Compared to open surgery, the laparoscopic surgery was a strong protective factor for PPOI after adjusting related variables (OR = 0.17, CI: 0.05‐0.52, P = .002). There was an interaction between surgical methods and the postoperative WBC level (P for interaction = .007). In the two group stratified analysis of WBC, laparoscopic surgery had a significant lower risk of PPOI than open group for the patients with WBC counts above the middle level in crude or adjusted models. This result remained significantly in the three group stratified analysis for the patients with WBC counts in the middle and or high tertile groups.ConclusionsPPOI is a common postoperative complication of patients after gastrectomy. Laparoscopic surgery is associated with decreased risk of PPOI in gastric surgery. Patients who underwent open surgery and presented with high level of WBC should be cautious with PPOI.
PTTG1 is involved in TNF‐α‐related hepatocellular carcinoma via the induction of c‐myc
Authors: Lin Xianyi , Yang Yidong , Guo Yunwei , Liu Huiling , Jiang Jie , Zheng Fengping , Wu Bin 
Published: August 2019

AbstractHepatocellular carcinoma (HCC) is a malignant disease caused by a variety of factors. However, the genomic and molecular aberrations in HCC are largely unknown. Herein, pituitary tumor transforming gene 1 (PTTG1) was discovered as a potential inflammation‐related oncogene in HCC, and its functions and molecular mechanisms were investigated. mRNA expression microarray, real‐time polymerase chain reaction (PCR), immunohistochemistry, and western blotting analyses revealed that PTTG1 is upregulated in HCC. Further in vitro and in vivo studies indicated that the proinflammatory cytokine tumor necrosis factor‐α (TNF‐α) induces PTTG1 expression, and PTTG1 was found to upregulate c‐myc, a well‐known oncogene. Downregulation of PTTG1 reduced c‐myc and proliferating cell nuclear antigen (PCNA) expression and inhibited cell proliferation. Interestingly, inhibition of c‐myc by 10058‐F4 did not affect PTTG1, which suggests that PTTG1 regulates c‐myc expression. Furthermore, PTTG1 expression levels are inversely correlated with HCC patient survival, indicating an independent prognostic biomarker for patients with HCC. Our data demonstrate that PTTG1 is involved in TNF‐α‐related HCC via c‐myc induction and that PTTG1 may be a potential therapeutic target for HCC.
Covalent versus Noncovalent Binding of Ruthenium η6‐p‐Cymene Complexes to Zinc‐Finger Protein NCp7
Authors: Sheng Yaping , Hou Zhuanghao , Cui Shiyong , Cao Kaiming , Yuan Siming , Sun Mei , Kljun Jakob , Huang Guangming , Turel Iztok , Liu Yangzhong 
Published: August 2019

AbstractRuthenium–arene complexes are a unique class of organometallic compounds that have been shown to have prominent therapeutic potencies. Here, we have investigated the interactions of Ru‐cymene complexes with a zinc‐finger protein NCp7, aiming to understand the effects of various ligands on the reaction. Five different binding modes were observed on selected Ru‐complexes. Ru‐cymene complex can bind to proteins through either noncovalent binding alone or through a combination of covalent and noncovalent binding modes. Moreover, the noncovalent interaction can promote the coordination of RuII to NCp7, resulting synergistic effects of the different ligands. The binding of Ru(Cym) complexes leads to dysfunction of NCp7 through zinc‐ejection and structural perturbation. These results indicate that the reactivity of Ru‐complexes can be modulated by ligands through different approaches, which could be closely correlated to their different therapeutic effects.
Strategies for Bioelectrochemical CO2 Reduction
Authors: Yuan Mengwei , Kummer Matthew J. , Minteer Shelley D. 
Published: August 2019

AbstractAtmospheric CO2 is a cheap and abundant source of carbon for synthetic applications. However, the stability of CO2 makes its conversion to other carbon compounds difficult and has prompted the extensive development of CO2 reduction catalysts. Bioelectrocatalysts are generally more selective, highly efficient, can operate under mild conditions, and use electricity as the sole reducing agent. Improving the communication between an electrode and a bioelectrocatalyst remains a significant area of development. Through the examples of CO2 reduction catalyzed by electroactive enzymes and whole cells, recent advancements in this area are compared and contrasted.
Pulsed EPR Dipolar Spectroscopy on Spin Pairs with one Highly Anisotropic Spin Center: The Low‐Spin FeIII Case
Authors: Abdullin Dinar , Brehm Philipp , Fleck Nico , Spicher Sebastian , Grimme Stefan , Schiemann Olav 
Published: August 2019

AbstractPulsed electron paramagnetic resonance (EPR) dipolar spectroscopy (PDS) offers several methods for measuring dipolar coupling constants and thus the distance between electron spin centers. Up to now, PDS measurements have been mostly applied to spin centers whose g‐anisotropies are moderate and therefore have a negligible effect on the dipolar coupling constants. In contrast, spin centers with large g‐anisotropy yield dipolar coupling constants that depend on the g‐values. In this case, the usual methods of extracting distances from the raw PDS data cannot be applied. Here, the effect of the g‐anisotropy on PDS data is studied in detail on the example of the low‐spin Fe3+ ion. First, this effect is described theoretically, using the work of Bedilo and Maryasov (Appl. Magn. Reson. 2006, 30, 683–702) as a basis. Then, two known Fe3+/nitroxide compounds and one new Fe3+/trityl compound were synthesized and PDS measurements were carried out on them using a method called relaxation induced dipolar modulation enhancement (RIDME). Based on the theoretical results, a RIDME data analysis procedure was developed, which facilitated the extraction of the inter‐spin distance and the orientation of the inter‐spin vector relative to the Fe3+ g‐tensor frame from the RIDME data. The accuracy of the determined distances and orientations was confirmed by comparison with MD simulations. This method can thus be applied to the highly relevant class of metalloproteins with, for example, low‐spin Fe3+ ions.
N‐Heterocyclic Carbenes as Key Intermediates in the Synthesis of Fused, Mesoionic, Tricyclic Heterocycles
Authors: Benaissa Idir , Pallova Lenka , Morantin Marie‐Emilie , Lafitte Thomas , Huynh Mathieu , Barthes Cécile , Vendier Laure , Lugan Noël , Bastin Stéphanie , César Vincent 
Published: August 2019

AbstractCoupling between 5‐bromoimidazo[1,5‐a]pyridinium salts and malonate or arylacetate esters leads to a facile and straightforward access to the new mesoionic, fused, tricyclic system of imidazo[2,1,5‐cd]indolizinium‐3‐olate. Mechanistic studies show that the reaction pathway consists of nucleophilic aromatic substitution on the cationic, bicyclic heterocycle by an enolate‐type moiety and in the nucleophilic attack of a transient free N‐heterocyclic carbene (NHC) species on the ester group; the relative order of these two steps depends on the nature of the starting ester. This work highlights the valuable implementation of free NHC species as key intermediates in synthetic chemistry, beyond their classical use as stabilizing ligands or organocatalysts.
Correlating Oxygen Reduction Reaction Activity and Structural Rearrangements in MgO‐Supported Platinum Nanoparticles
Authors: Rossi Kevin , Asara Gian Giacomo , Baletto Francesca 
Published: August 2019

AbstractWe develop a multi‐scale approach towards the design of metallic nanoparticles with applications as catalysts in electrochemical reactions. The here discussed method exploits the relationship between nanoparticle architecture and electrochemical activity and is applied to study the catalytic properties of MgO(100)‐supported Pt nanosystems undergoing solid‐solid and solid‐liquid transitions. We observe that a major increment in the activity is associated to the reconstruction of the interface layers, supporting the need for a full geometrical characterisation of such structures also when in‐operando.
A comprehensive circuit model for evaluating the response of silicon photomultipliers in continuous wave light regime
Authors: Siminfar Amir Reza , Shoaei Omid 
Published: August 2019

SummaryIn this paper, a comprehensive dynamic model for silicon photomultiplier (SiPM) detectors is proposed to investigate their response when exposed to the light of any wavelength and relatively high intensity. Also, a procedure is proposed to perform reliable circuit‐level simulations to predict the response of these detectors under various photon rates. The approach of dynamic model is based on the state of microcells in terms of overvoltage, elapsed recharging time, and their effect on the triggering probability with which the detector current and voltage can be accurately simulated. Using the proposed model, the SiPM behaviour is examined under various continuous illumination power in simulation. The effectiveness of the proposed model and the simulation method are verified by experimental results extracted from two SiPM detectors.
Comparative analysis to determine the accuracy of fractional derivatives in modeling supercapacitors
Authors: Carreño C.A. , Rosales J.J. , Merchan L.R. , Lozano J.M. , Godínez F.A. 
Published: August 2019

SummaryIn this paper, we study a supercapacitor model represented by an equivalent RC circuit considering five different types of derivatives: Caputo, Caputo‐Fabrizio, and Atangana‐Baleanu fractional derivatives and the conformable and integer‐order derivatives. A set of experimental data from six commercial supercapacitors are used to estimate the parameter values for each derivative model by applying interior point optimization. The results show that the most accurate approach is achieved with the conformable derivative followed by the Caputo fractional derivative.
Link quality estimation for arbitrary packet sizes over wireless links using packet reception events
Authors: Jacobsson Martin , Rohner Christian 
Published: August 2019

SummaryThe packet error rate of wireless links is known to increase with the length of packets. Yet, packet length is rarely taken into account in protocols and algorithms estimating the packet error rate. Still, it is an important factor that higher layer protocols need to be aware of. In this article, we systematically measure the relationship between packet length and packet error rate over a wide range of wireless links and technologies. On the basis of our measurements, we propose a simple empirical model that can capture this behavior. Using this model, multiple methods are proposed that can estimate the packet error rate for any packet length by sampling the link. We consider methods based on hello packets with controlled packet lengths as well as data packets, where the transmitted packet lengths cannot be controlled. We investigate the accuracy of the different estimation methods in various situations and show how they are able to predict the delivery ratio for different packet sizes.