Excretion of heavy metals from the biliary tract and its association with pancreato-biliary malignancy

PhD ThesisBiliary and pancreatic cancers are associated with poor prognosis and high mortality. A variety of genetic and environmental factors have been implicated as possible causes of these cancers. New epidemiological studies are looking into the possible role of heavy metals such as lead, chromium, nickel and cadmium as carcinogens. Studies from areas of wide geographical differences such as Egypt, USA and India have reported a possible association of heavy metals such as lead and cadmium with pancreato-biliary malignancy. These studies were from areas of significant environmental pollution with these metals due to the proximity of heavy industry or mining activities. No association has been demonstrated between metal exposure and pancreato-biliary malignancy in areas of low environmental pollution. Aim The aim of this study was to look at a possible association between excretion of heavy metals from the biliary tract and pancreato-biliary malignancy in an industrial area in the North-East of England. Materials and Methods Patients with malignant biliary obstruction admitted to a tertiary referral centre were identified prospectively. Bile was collected either during endoscopic retrograde cholangiography (ERC), percutaneous transhepatic 10 cholangiography (PTC) or during biliary tract surgery. Bile was also collected from patients with benign biliary disease to act as controls. The bile samples were analyzed for concentrations of lead, copper, zinc, cadmium, chromium and nickel using atomic absorption spectrometry after pre-treatment by the acid digestion method. The mean levels of every metal in the study groups (biliary malignancy and pancreatic malignancy) and the control group were compared by using SPSS 16© (SPSS Inc) statistical software. It was uncertain whether there would be a measurable quantity of heavy metals in the bile collected during the above procedures and therefore it was felt necessary to perform a small pilot study to standardize the methods and address any possible difficulties. Results Bile samples collected from 107 patients over a period of 18 months were included in this study. As part of the pilot study two different methods of purification of bile (acid digestion vs syringe filtration) were evaluated and acid digestion was chosen as a more reliable method. For the main study, after exclusion due to inadequate volume of sample, a total of 127 bile samples from 98 patients (43 male, 55 female, median age 65.82 years, range 20-82 years) were analyzed. On final analysis, the malignant group comprised of 3 subgroups: pancreatic cancer, biliary cancer and periampullary cancer. Results from these 3 groups were compared with those from the benign control group. The groups were sex-matched but there was a significant difference in age distribution between the benign and 11 malignant groups (p<0.001). Bile samples were obtained from both gallbladder (GB) and common bile duct (CBD) in 33 patients and from either of these sources in the remainder. There was a strong positive correlation between the concentration of each metal when obtained from either GB or CBD. The main results of this study have shown that copper was present at significantly higher levels in the benign control group (p=0.004) and that cadmium was present at significantly higher levels in the malignant groups (p=0.02). There was no significant difference amongst the groups for the other heavy metals. Discussion Cadmium has been implicated as a possible environmental carcinogen for various malignancies, including pancreatic cancer. Most studies that show this association are from areas of high environmental pollution. The present study supports this association. There is evidence of excess environmental exposure to heavy metals, including cadmium, in the North-East of England. This exposure is mainly in relation to mining activities in the past in this region and is mainly noticed downstream along the rivers draining the areas with significant mining history. The results of this study support the possible association between heavy metal exposure and pancreatic and biliary malignancy. Further research is needed to establish the specific carcinogenic role of heavy metals such as cadmium in pancreato-biliary malignancies

Automated Camera Calibration for Robot Soccer

Non

Autonomous Anthropomorphic Robotic System with Low-Cost Colour Sensors to Monitor Plant Growth in a Laboratory

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Performance Comparison of A New Non-RSSI Based Wireless Transmission Power Control Protocol with RSSI Based Methods:Experimentation with Real World Data

In this paper, simulations with MATLAB are used to compare the performance of a RSSI-based output power control with non-RSSI based adaptive power in terms of saving energy and extending the lifetime of battery powered wireless sensor nodes. This non-RSSI (received signal strength indicator) based adaptive power control algorithm does not use RSSI side information to estimate the link quality. The non-RSSI based approach has a unique methodology to choose the appropriate power level. It has drop-off algorithm that enables it to come back from a higher to a lower power level when deemed necessary. The performance parameters are compared with the RSSI-based adaptive power control algorithm and fixed power transmission. In order to evaluate the protocols in the real world scenarios, RSSI data from different indoor radio environments are collected. In simulation, these RSSI values are used as an input to the RSSI based power control algorithm to calculate the packet success rates and the energy expenditures. In this paper we present extensive analysis of the simulation results to find out the advantages and limitations of the non-RSSI based adaptive power control algorithm under different channel conditions

Intelligent classroom management system

This thesis report is submitted in partial fulfillment of the requirements for the degree of Bachelor of Science in Electrical and Electronic Engineering, 2013.Cataloged from PDF version of thesis report.Includes bibliographical references (page 51).Modern day class rooms are equipped with electronic devices that have supporting software to improve and facilitate teaching methods. However, it is often seen that significant class time is wasted on taking attendance, or the class may face interruption due to late entries of students and disturbances such as the manual control of fan and light. Therefore, to overcome those problems a feasible system is created in this thesis project that will have no physical intervention from teachers, students or floor attendance. Thus, the system will facilitate the smooth running of the scheduled classes at our university, and minimize time loss.Md. Nahal IslamFarah TabassumGourab Kumar SarkerDhrubashish SenB. Electrical and Electronic Engineerin

Surgery for Hilar cholangiocarcinoma: the Newcastle-upon-Tyne Liver Unit experience

Background: Hilar cholangiocarcinoma (HCCA) arises from the confluence of the common hepatic duct and has a poor prognosis. If resectable, an extended left (eLH) or right hemihepatectomy (eRH) is usually required to provide oncological clearance. We reviewed outcomes for patients with HCCA managed at our centre. Methods: Electronic records of patients referred to our centre for HCCA were retrospectively reviewed. The Kaplan–Meier method was used to estimate overall survival (OS) with the log rank test used for significance (p &lt; 0.05). A Cox regression was performed to ascertain factors that may influence survival. Results: 156 HCCA patients were identified (44 resected versus 112 non-resected). Resected patients had longer OS compared to non-resected patients (50.3 versus 9.8 months, p &lt; 0.001). Patients who underwent an eLH (n = 15) had significantly longer OS at 3 years compared to eRH patients (67.7 vs. 42.1%, respectively; p = 0.007). An eLH was an independent predictor of survival (HR 0.43, p = 0.04). Lymph node positivity (n = 23, hazard ratio 1.72, p = 0.027) and the presence of microvascular invasion (n = 28, hazard ratio 1.78, p = 0.047) were independent predictors of mortality. The frequency of lymph node positivity and microvascular invasion did not differ between eLH and eRH patients (p &gt; 0.05). Conclusion: Patients undergoing an eLH for HCCA have significantly better long-term outcomes compared to those undergoing eRH, independent of other pathological variables. The functional liver remnant (FLR) is usually smaller following eRH, resulting in a higher risk of post-operative liver failure. Combining CT volumetry with PVE may result in better prediction and optimisation of the FLR in the context of eRH for HCCA. Novel findings: An extended left hemihepatectomy is an independent predictor of survival; investigation into the precise interaction between left- and right-sided resections and pre- and post-embolization liver volume is warranted

The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy

Background: The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations. Methods: Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (> 90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves. Results: After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45–85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations > 90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SE = 0.013, p  90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score. Conclusion: The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care

MUSiC : a model-unspecific search for new physics in proton-proton collisions at root s=13TeV

Results of the Model Unspecific Search in CMS (MUSiC), using proton-proton collision data recorded at the LHC at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1), are presented. The MUSiC analysis searches for anomalies that could be signatures of physics beyond the standard model. The analysis is based on the comparison of observed data with the standard model prediction, as determined from simulation, in several hundred final states and multiple kinematic distributions. Events containing at least one electron or muon are classified based on their final state topology, and an automated search algorithm surveys the observed data for deviations from the prediction. The sensitivity of the search is validated using multiple methods. No significant deviations from the predictions have been observed. For a wide range of final state topologies, agreement is found between the data and the standard model simulation. This analysis complements dedicated search analyses by significantly expanding the range of final states covered using a model independent approach with the largest data set to date to probe phase space regions beyond the reach of previous general searches.Peer reviewe