Objective: The aim of this study was to evaluate a new underfill-function in a POCT-instrument from HemoCue AB (Ängelholm, Sweden). The instrument is in use today among diabetes patients for self-monitoring blood glucose (SMBG). The new function is supposed to guarantee that measuring only will be performed on a sufficient sample volume to assure that the correct glucose value is received. Methods and results: Blood samples (whole blood) from 12 patients were analysed with the instrument. Measuring were performed using different volumes in the cuvette. Full cuvette, 3µL, 2µL, 1µL and a measuring on an empty cuvette. The instrument performed measurements on all volumes added to the cuvette except for the empty cuvette. The less sample volume that was used the lower glucose values were reported by the instrument. Conclusions: The new under fill-function did not work satisfactory. If such function would be more reliable it would be beneficial for the patient controlling hers/his bloodglucose provided that the testing procedure is being correctly done. This is very important because the results are often used to treat the patient.

No description available.

Yes / Acute kidney injury (AKI) can occur rarely in patients exposed to iodinated contrast and result in contrast-induced AKI (CI-AKI). A key risk factor is the presence of pre-existing chronic kidney disease (CKD), therefore it is important to assess patient risk and obtain kidney function measurement prior to administration. Point of care (PoC) testing provides an alternative strategy but there remains uncertainty, with respect to diagnostic accuracy and clinical utility. A device study compared three PoC analysers (Nova StatSensor, Abbott i-STAT, Radiometer ABL800 FLEX) with a reference laboratory standard (Roche Cobas 8000 series, enzymatic creatinine). Three hundred adult patients attending a UK hospital phlebotomy department were recruited to have additional blood samples for analysis on the PoC devices. The ABL800 FLEX had the strongest concordance with laboratory measured serum creatinine (mean bias=-0.86, 95% limits of agreement = -9.6 to 7.9) followed by the i-STAT (average bias=3.88, 95% limits of agreement = -8.8 to 16.6) and StatSensor (average bias=3.56, 95% limits of agreement = -27.7 to 34.8). In risk classification, the ABL800 FLEX and i-STAT identified all patients with an eGFR≤30, whereas the StatSensor resulted in a small number of missed high-risk cases (n=4/13) and also operated outside of the established performance goals. The screening of patients at risk of CI-AKI may be feasible with PoC technology. However in this study it was identified that the analyser concordance with the laboratory reference varies. It is proposed that further research exploring PoC implementation in imaging department pathways is needed. / Yorkshire and Humber Academic Health Science Network (Grant Number: YHP0318)

<p>Point of care (POC) diagnosis is essential in personalized treatment to obtain effective clinical outcomes when the patient is on site. And Mass spectrometry (MS) system promotes the applications of rapid sampling ionization, which could be a tool for fast disease determination. In this thesis, a miniature MS system was firstly developed for POC tissue analysis. Lipid profile in rat organs were demonstrated. By coupling with online Paternò–Büchi (PB) reaction, fast determination of lipid C=C bond location isomers was realized. The system was applied to quantitatively analyze the change of lipid C=C location isomers between mouse normal and cancerous samples. The intensity ratio of fatty acid 18:1 (D9) and 18:1 (D11) in wild type breast tissue was calculated to be 2.881, while the ratio in tumor breast tissue was 0.667. The direct sampling-based miniature MS system is potential for POC analysis of lipid profiles and lipid biomarkers discovery.</p> <p>Secondly, an integration of paper-capillary spray and MS make it possible to analyze dried blood samples instantly in clinical laboratory and hospital. Quantitation of ratio between deuterate Phenylalanine and deuterate Tyrosine was achieved by using paper spray and paper-capillary spray MS directly, without any pretreatment of blood samples. Furthermore, these methods could generate calibration curves which enable the calculation of Phenylalanine concentration in whole human blood within 60 seconds. This disposable design is a promising application for point-of-care (POC) PKU analysis in newborn screening. </p> <p>At last, an increased in free fatty acids (FFAs) of cereals was observed during storage, and a simple and direct rice quality assessment was performed using nanoESI (Nano-Electrospray Ionization) mass spectrometry method. Six fatty acids including palmitic, oleic, and linoleic acids were compared between different rice species, growth regions and harvest years. 2D and 3D linear discriminant analysis (LDA) methods were deployed and a good sample separation was achieved. This direct sampling method of extracting FAs from rice surface combined with MS is suitable for industrial use in rapid identification for large number of samples.</p>

No description available.

Point-of-care testing (POCT) is defined as medical testing at or near the site of patient care and has become a critical component of the diagnostic industry. POCT has many advantages over tests in centralized laboratories including small reagent volumes, small size, rapid turnaround time, cost-effectiveness, low power consumption and functional integration of multiple devices. Paper-based POCT sensors are a new alternative technology for fabricating simple, low-cost, portable and disposable analytical devices for clinical diagnosis. The focus of this dissertation was to develop simple, rapid and low cost paper-based POCT sensors with high sensitivity and portability for disease biomarker detection. Lateral flow strips (LFS) were used as the basic platform as it provides several key advantages such as simplicity, fast response time, on site and cost-effectiveness, and it can be used to detect specific substances including small molecules, large proteins and even whole pathogens, in a sample by immunological reactions. Earlier designs of paper strips lacked the quantitative information of the analyte concentration and could only provide single analyte detection at a time. In this study, a series of modifications were made to upgrade the platform to compensate for these limitations. First, we developed a gold nanoparticle based LFS for qualitative colorimetrical detection of bladder cancer related biomarkers in standard solutions and in urine samples. Second, by incorporating an image processing program “ImageJ”, a semi-quantitative LFS platform was established. The capability of the strip was evaluated by testing a small DNA oxidative damage biomarker in urine and cell culture models. Third, we combined the electrochemical method and colorimetrical method for quantitative biomarker detection. Finally, we integrated a commercialized blood glucose meter to quantitatively detection of two non-glucose biomarkers by converting their signals to that of glucose. The upgraded sensor could provide a noninvasive, rapid, visual, quantitative and convenient detection platform for various disease biomarkers. In addition, this platform does not require expensive equipments or trained personnel, deeming it suitable for use as a simple, economical and portable field kit for on-site biomarker monitoring in a variety of clinical settings.

Preliminary investigation at the beginning of this research showed that informatics on point-of-care (POC) devices was limited to basic data generation and processing. This thesis is based on publications of several studies during the course of the research. The aim of the research is to model and analyse information generation and exchange in telehealth systems and to identify and analyse the capabilities of these systems in managing chronic diseases which utilise point-of-care devices. The objectives to meet the aim are as follows: (i) to review the state-of-the-art in informatics and decision support on point-of-care devices. (ii) to assess the current level of servitization of POC devices used within the home environment. (iii) to identify current models of information generation and exchange for POC devices using a telehealth perspective. (iv) to identify the capabilities of telehealth systems. (v) to evaluate key components of telehealth systems (i.e. POC devices and intermediate devices). (vi) to analyse the capabilities of telehealth systems as enablers to a healthcare policy. The literature review showed that data transfer from devices is an important part of generating information. The implication of this is that future designs of devices should have efficient ways of transferring data to minimise the errors that may be introduced through manual data entry/transfer. The full impact of a servitized model for point-of-care devices is possible within a telehealth system, since capabilities of interpreting data for the patient will be offered as a service (c.f. NHS Direct). This research helped to deduce components of telehealth systems which are important in supporting informatics and decision making for actors of the system. These included actors and devices. Telehealth systems also help facilitate the exchange of data to help decision making to be faster for all actors concerned. This research has shown that a large number of capability categories existed for the patients and health professionals. There were no capabilities related to the caregiver that had a direct impact on the patient and health professional. This was not surprising since the numbers of caregivers in current telehealth systems was low. Two types of intermediate devices were identified in telehealth systems: generic and proprietary. Patients and caregivers used both types, while health professionals only used generic devices. However, there was a higher incidence of proprietary devices used by patients. Proprietary devices possess features to support patients better thus promoting their independence in managing their chronic condition. This research developed a six-step methodology for working from government objectives to appropriate telehealth capability categories. This helped to determine objectives for which a telehealth system is suitable.

Human immunodeficiency virus type 1 (HIV-1) still causes a chronic infection that affects millions of individuals worldwide. The infection remains incurable and presents a huge challenge for treatment, as it tends to disable a patient’s immune system. Although the current HIV-1 treatment regime possesses the ability to reduce the viral load to undetectable limits, complete eradication of the virus cannot be achieved while latent HIV-1 reservoirs go unchallenged. These viral reservoirs are established early on during HIV-1 infection and are a major hurdle since they remain unaffected by antiretroviral drugs and have the ability to replenish systemic infections once treatment is interrupted. Further ailments with the highly active antiretroviral therapy (HAART) include issues such as the cumbersome lifelong treatment, development of drug resistant strains of HIV-1 and adverse side effects. Contrarily, early diagnosis of the HIV-1 infection and HIV-1 treatment is a major challenge in resource-limited countries. The current available diagnostic tools for HIV-1 infection have shown to be highly accurate in monitoring CD4+ T lymphocyte count and viral load measurements. However, these tests such as enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) which are highly efficient, are usually very expensive with complex operation, time consuming, require skilled personnel and training that makes them incompatible for the application in resource-limited areas. Therefore, this raises the urgent need for developing an HIV point of care (POC) diagnostic tool that is label-free, highly specific and sensitive as well as therapeutic modalities, which can be used to address the previously mentioned challenges. Much research has been conducted to resolve these problems but to date, there has not been application of laser and/or photonics in HIV research. Therefore, in this thesis a femtosecond laser was used in HIV infected cells for targeted antiretroviral drug delivery while preserving their viability. For the first time according to our knowledge, antiretrovirals (ARVs) that target all the life stages of the HIV-1 life cycle were utilized and they proved to be significant in reducing HIV-1 infection. Furthermore, through the employment of a continuous wave laser at 640 nm, for the first time, surface plasmon resonance was conducted to facilitate label-free detection of HIV-1. Success of these laser based technologies will open doors for incorporation in POC HIV diagnostic tools for the detection and treatment monitoring of HIV in resource-limited settings. / Physics / Ph. D. (Physics)