Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Cinnamomum cassia ameliorates Ni-NPs-induced liver and kidney damage in male Sprague Dawley rats

Nickel nanoparticles (Ni-NPs) have been widely used in various industries related to electronics, ceramics, textiles, and nanomedicine. Ambient and occupational exposure to Ni-NPs may bring about potential detrimental effects on animals and humans. Thus, there is a growing effort to identify compounds that can ameliorate NPs-associated pathophysiologies. The present study examined Cinnamomum cassia (C. cassia) bark extracts (CMBE) for its ameliorative activity against Ni-NPs-induced pathophysiological and histopathological alterations in male Sprague Dawley rats. The biochemical analyses revealed that dosing rats with Ni-NPs at 10 mg/kg/body weight (b.w.) significantly altered the normal structural and biochemical adaptations in the liver and kidney. Conversely, supplementations with CMBE at different doses (225, 200, and 175 mg/kg/b.w. of rat) ameliorated the altered blood biochemistry and reduced the biomarkers of liver and kidney function considerably (p < 0.05) in a dose-dependent manner. However, the best results were at 225 mg/kg/b.w. of rat. The study provided preliminary information about the protective effect of C. cassia against Ni-NPs indicated liver and kidney damages. Future investigations are needed to explore C. cassia mechanism of action and isolation of single constituents of C. cassia to assess their pharmaceutical importance accordingly.

Sentiment analysis of tweets through Altmetrics: A machine learning approach

The purpose of the study is to (a) contribute to annotating an Altmetrics dataset across five disciplines, (b) undertake sentiment analysis using various machine learning and natural language processing–based algorithms, (c) identify the best-performing model and (d) provide a Python library for sentiment analysis of an Altmetrics dataset. First, the researchers gave a set of guidelines to two human annotators familiar with the task of related tweet annotation of scientific literature. They duly labelled the sentiments, achieving an inter-annotator agreement (IAA) of 0.80 (Cohen’s Kappa). Then, the same experiments were run on two versions of the dataset: one with tweets in English and the other with tweets in 23 languages, including English. Using 6388 tweets about 300 papers indexed in Web of Science, the effectiveness of employed machine learning and natural language processing models was measured by comparing with well-known sentiment analysis models, that is, SentiStrength and Sentiment140, as the baseline. It was proved that Support Vector Machine with uni-gram outperformed all the other classifiers and baseline methods employed, with an accuracy of over 85%, followed by Logistic Regression at 83% accuracy and Naïve Bayes at 80%. The precision, recall and F1 scores for Support Vector Machine, Logistic Regression and Naïve Bayes were (0.89, 0.86, 0.86), (0.86, 0.83, 0.80) and (0.85, 0.81, 0.76), respectively.

Exploring the presence of dental anomalies as a consequence of treatment of malignancy: A case report

Simultaneous presentation of tuberculosis (TB) and lymphoma in a young child is indeed a very rare entity. Malignancy such as Hodgkin's disease (HD) most commonly causes suppression of the cell-mediated immunity, which makes the individual, especially children, more prone to tuberculous infection. One of the non-life threatening complications in these young cancer survivors is the associated dental anomalies. These can seriously impair the quality of life of teenagers and young adults. Higher incidence of caries, discoloration of teeth or even early loss of teeth requiring dental prosthesis, can be associated with the use of cytostatic drugs. These drugs can also disturb odontogenesis, resulting in the absence of tooth buds, microdontia, dilacerations or shortening of tooth roots. Some of the anticancer drugs, including busulfan, cyclophosphamide, doxorubicin etc. May particularly play a significant role in the development of dental anomalies. This paper is a short review and case report of an 11 year old child having oligodontia and secondary dental complications caused as a side effect of treatment of Hodgkin's lymphoma with Tuberculous Lymphadenitis.

Pharmacokinetics of thymoquinone in layer chickens following oral and intravenous administration

Thymoquinone (TQ) is the major constituent of Nigella sativa and known to possess a variety of pharmacological effects. This study was designed to evaluate the pharmacokinetic profile of TQ following oral (PO) and intravenous (IV) administration in layer chickens. The layer chickens were equally divided into two groups (six chickens in each group, total 12 chickens), and TQ was administered via PO and IV routes. For PO route, the dose was 20 mg/kg b.w. and for IV route, 5 mg/kg b.w. was administered, respectively. A sensitive and accurate High-Performance Liquid Chromatography (HPLC) technique was validated for the quantification of TQ from plasma. The limit of detection (LOD) and limit of quantification (LOQ) were 0.02 µg/ml and 0.05 µg/ml, respectively with >80% recovery. Maximum plasma concentration (C_max ) following PO and IV administration was 8.805 and 4.497 µg/ml, respectively, while time to reach at maximum concentration (T_max ) was 1 and 0.1 hr, respectively. The elimination half-lives were recorded as 1.02 and 0.978 hr, whereas the mean residence times were 1.79 and 1.036 hr following both PO and IV administration, respectively. The 85% PO bioavailability was indicative that TQ could be used for various therapeutic purposes in layer chickens.

Scientific collaboration networks in Pakistan and their impact on institutional research performance

Purpose

The purpose of this paper is to analyze the scientific collaboration of institutions and its impact on institutional research performance in terms of productivity and quality. The researchers examined the local and international collaborations that have a great impact on institutional performance.

Design/methodology/approach

Collaboration dependence measure was used to investigate the impact of an institution on external information. Based on this information, the authors used “index of gain in impact through collaboration” to find the impact of collaborated publications in institutional research performance. Bibliographic data between 1996 and 2010 retrieved from Scopus were used to conduct current study. The authors carried out the case study of top institutes of Pakistan in terms of publication count to elaborate the difference between high performing institutions and those who gain disproportionally in terms of perceived quality of their output because of local or international collaboration.

Findings

The results showed that the collaboration of developing countries institutes on international level had a great impact on institutional performance and they gain more benefit than local collaboration. Altogether, the scientific collaboration has a positive impact on institutional performance as measured by the cumulative source normalized impact per paper of their publications. The findings could also help researchers to find out appropriate collaboration partners.

Originality/value

This study has revealed some salient characteristics of collaboration in academic research. It becomes apparent that collaboration intensity is not uniform, but in general, the average quality of scientific production is the variable that most often correlates positively with the collaboration intensity of universities.

Supramolecular self-assembly and physical-gel formation in disc-like liquid crystals: a scalable predictive model for gelation and an application in photovoltaics

The application of triphenylene-based discotic liquid crystal derivatives as physical gelators is investigated. In particular, we focus on 2,3,6,7,10,11-hexakis-pentyloxytriphenylene (HAT5) and the longer alkyl chain homologue (HAT6). The driving mechanisms behind and parameter space of non-covalent physical gel formation is studied. A Hansen solubility parameter (HSP) approach is used to predict physical gelation of these disc-like liquid crystalline molecules in a variety of common organic and inorganic solvents important to electrochemical devices. Our results show that HSP analysis is very useful for the prediction of gel formation. The results are transferrable and can form the basis for future investigations into liquid crystalline physical gels. Furthermore, we use acetonitrile as a solvent and apply the gels as electrolytes in dye sensitized solar cells. It is observed that using a binary mixture of gelators results in average photovoltaic power conversion efficiencies as high as 7.21%, compared to a 5.9% reference electrolyte. This is attributed to a reduction in electron recombination at the n-type interface and provides further insight about hybrid gelators. Coupled with an increase in device stability, the results are promising for gel-based dye sensitized solar cells as well as potentially other electrolytic devices such as batteries and supercapacitors.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.