The application of biomedical engineering techniques to the diagnosis and management of tropical diseases: A review

This paper reviews a number of biomedical engineering approaches to help aid in the detection and treatment of tropical diseases such as dengue, malaria, cholera, schistosomiasis, lymphatic filariasis, ebola, leprosy, leishmaniasis, and American trypanosomiasis (Chagas). Many different forms of non-invasive approaches such as ultrasound, echocardiography and electrocardiography, bioelectrical impedance, optical detection, simplified and rapid serological tests such as lab-on-chip and micro-/nano-fluidic platforms and medical support systems such as artificial intelligence clinical support systems are discussed. The paper also reviewed the novel clinical diagnosis and management systems using artificial intelligence and bioelectrical impedance techniques for dengue clinical applications

Biochemical Testing

Clinical Correlation and Diagnosis highlights the improvements in methodological approaches for the purposes of disease diagnosis and health research. Chapters cover such topics as serum protein electrophoresis, urinary iodine measurement, blood collection tubes, semi-solid phase assay and advancement in analytical and bioanalytical techniques, and serological diagnostic tools for Zika virus, among other subjects. All these will not be possible without a proper laboratory management where this book also includes the Tissue Bank ATMP Production as a model. The chapters are expected to provide a new perspective in health science which may trigger a further exploration into the diagnostic and research field

Biomarker discovery for cervical cancer

Proteomics of human boy fluids is still in its early stage of development with major methodological challenges ahead. This implies that much attention is given to improving the methods and strategies. One major challenge is that many samples that have been acquired in the past may not fulfill the stringent requirements of storage and sample preparation to allow comparable proteomics analyses. It is therefore important to assess the factors that may affect the final proteomics result through systematic and reproducible analyses. Therefore accuracy and sensitivity of the analytical instrumentation is not the only critical factor in this research. Blood (plasma or serum) and urine can be easily sampled from patients or healthy volunteers and are therefore often the first choice when trying to discover novel biomarkers or biomarker patterns to diagnose cancer and other diseases. There are, however, drawbacks such as the masking of low-abundance by high abundance proteins and the possible effect of sampling and sample handling procedures (e.g. different times for blood clotting). A number of different approaches to deplete highly abundant proteins from human serum were studied throughout this thesis. Further, different analytical techniques were applied, such as a miniaturized, microfluidics-based LC-MS system (chip-LC-MS) to enhance overall sensitivity. It is shown that chip-LC-MS has at least twice the resolution of the previously used standard capillary LC-MS method. Since blood composition will change under the influence of external factors, the influence of clotting time on proteome of serum was studied. It was found that most proteins were not affected by clotting time except for those directly involved in this process, such as the fibrinopeptides. Next, we describe a more comprehensive approach for evaluating the influence of various pre-analytical parameters on the serum proteome. A factorial design strategy was applied to assess the importance of seven factors considered to be of relevance, including the level of hemolysis, the digestion conditions, and the storage conditions. Finally, we analyzed serum samples from cervical cancer patients at various stages of disease before and after treatment followed by data processing and statistical data analysis. While we did not discover major changes in the serum proteome using this method, subtle changes in the protein composition were observed in relation to treatment, the significance of which are being further investigated. It is thus demonstrated that the described methods are applicable to highly complex body fluids such as serum and that further studies into the relevance of the discovered changes of the serum proteome are warranted.

Saliva Testing: A New Tool added to the Pathologist’s Armamentarium

Saliva harbors a wide spectrum of proteins/ peptides, nucleic acids, electrolytes, and hormones, that originate from multiple local and systemic sources. Research has identified many of these biomolecules as disease specific, which, along with recent availability of highly sensitive detection technology, has become the driving force for the development of saliva based diagnostic tools. Although saliva offers many advantages over blood, including ease of collection and minimal risk of contracting infections, there are some limitations in its application in clinical setting. These include diurnal variation in salivary composition, influenced by the method of collection, and 1000 folds less concentration of salivary biomolecules as compared to blood etc. Studies have shown mixed results regarding the clinical relevance of analytical tools developed so far. There is a need for further round robin testing, validation studies for reproducibility, sensitivity and specificity and clinical trials on large number of patients. The development of specific and standardized analytical tools, establishing reference ranges, individual cut- off values, and standardization of collection devices and methods will be other major challenges. In future we are likely to see the increased utilization of saliva as a diagnostic fluid in routine clinical practice and it may become the first choice over blood, especially in some specific situations such as in obese and hemophilic patient

The development of microfluidic paper-based analytical devices for point-of-care diagnosis of sheep scab

The recent growing interest and development of microfluidic paper-based analytical devices (μPADs) for point-of-care (POC) testing in human health in low-resource settings has great potential for the exploitation of these technologies in animal disease diagnosis. Sheep scab is a highly infectious, widespread and notifiable disease of sheep, which poses major economic and welfare concerns for the UK farming industry. The possibility of diagnosing sheep scab at the POC is, consequently, very important to controlling this disease. The overall aim of this project was, therefore, to develop μPADs based on a novel method of fabrication, in order to translate the existing lab-based sheep scab ELISA (Pso o 2) and a biomarker test for haptoglobin (Hp) into paper-based ELISA (P-ELISA), to enable POC diagnosis of this animal disease. In Chapter 3, the novel fabrication method is described, in Chapters 4 and 5, the translation of the lab-based ELISAs (Hp and Pso o 2 respectively) are explained and in Chapter 6 the development of a μPAD for incorporation of the POC tests into a multiplexed, rapid assay is covered. Experiments showed that both ELISAs were successfully transferred onto paper and that the devices developed were suitable for POC testing. This study has resulted in a novel fabrication method for μPADs, in successfully translated existing ELISAs to P-ELISA and in novel solutions for the POC diagnosis of an important veterinary disease

The development of microfluidic paper-based analytical devices for point-of-care diagnosis of sheep scab

The recent growing interest and development of microfluidic paper-based analytical devices (μPADs) for point-of-care (POC) testing in human health in low-resource settings has great potential for the exploitation of these technologies in animal disease diagnosis. Sheep scab is a highly infectious, widespread and notifiable disease of sheep, which poses major economic and welfare concerns for the UK farming industry. The possibility of diagnosing sheep scab at the POC is, consequently, very important to controlling this disease. The overall aim of this project was, therefore, to develop μPADs based on a novel method of fabrication, in order to translate the existing lab-based sheep scab ELISA (Pso o 2) and a biomarker test for haptoglobin (Hp) into paper-based ELISA (P-ELISA), to enable POC diagnosis of this animal disease. In Chapter 3, the novel fabrication method is described, in Chapters 4 and 5, the translation of the lab-based ELISAs (Hp and Pso o 2 respectively) are explained and in Chapter 6 the development of a μPAD for incorporation of the POC tests into a multiplexed, rapid assay is covered. Experiments showed that both ELISAs were successfully transferred onto paper and that the devices developed were suitable for POC testing. This study has resulted in a novel fabrication method for μPADs, in successfully translated existing ELISAs to P-ELISA and in novel solutions for the POC diagnosis of an important veterinary disease

Ultrafine Dielectrophoresis-based Technique for Virus and Biofluid Manipulation

abstract: Microfluidics has shown great potential in rapid isolation, sorting, and concentration of bioparticles upon its discovery. Over the past decades, significant improvements have been made in device fabrication techniques and microfluidic methodologies. As a result, considerable microfluidic-based isolation and concentration techniques have been developed, particularly for rapid pathogen detection. Among all microfluidic techniques, dielectrophoresis (DEP) is one of the most effective and efficient techniques to quickly isolate and separate polarizable particles under inhomogeneous electric field. To date, extensive studies have demonstrated that DEP devices are able to precisely manipulate cells ranging from over 10 μm (mammalian cells) down to about 1 μm (small bacteria). However, very limited DEP studies on manipulating submicron bioparticles, such as viruses, have been reported. In this dissertation, rapid capture and concentration of two different and representative types of virus particles (Sindbis virus and bacteriophage M13) with gradient insulator-based DEP (g-iDEP) has been demonstrated. Sindbis virus has a near-spherical shape with a diameter ~68 nm, while bacteriophage M13 has a filamentous shape with a length ~900 nm and a diameter ~6 nm. Under specific g-iDEP experimental conditions, the concentration of Sindbis virus can be increased two to six times within only a few seconds, using easily accessible voltages as low as 70 V. A similar phenomenon is also observed with bacteriophage M13. Meanwhile, their different DEP behavior predicts the potential of separating viruses with carefully designed microchannels and choices of experimental condition. DEP-based microfluidics also shows great potential in manipulating blood samples, specifically rapid separations of blood cells and proteins. To investigate the ability of g-iDEP device in blood sample manipulation, some proofs of principle work was accomplished including separating two cardiac disease-related proteins (myoglobin and heart-type fatty acid binding protein) and red blood cells (RBCs). Consistent separation was observed, showing retention of RBCs and passage of the two spiked protein biomarkers. The numerical concentration of RBCs was reduced (~70 percent after one minute) with the purified proteins available for detection or further processing. This study explores and extends the use of the device from differentiating similar particles to acting as a sample pretreatment step.Dissertation/ThesisDoctoral Dissertation Chemistry 201

Analytical methods for detection of human cytomegalovirus clinched biosensor a cutting-edge diagnostic tool

Abstract Human cytomegalovirus (HCMV) is a beta herpes-virus, which affects human being as a lifelong infection. HCMV is the prominent cause for the infections of congenital with a 1.0–2.4% incidence of live-births, along with possible severe classic cytomegalovirus. Crucial HCMV infection is usually asymptomatic in healthy hosts but it can cause severe or sometimes fatal illness in immuno-compromised neonates and individuals. Various conventional methods such as PCR, virus isolation, antigenemia test, histological and serological are available for detection of HCMV. Among all the analytical techniques, biosensors clinched as the most advanced technology, which offers many features such as simplicity, inexpensive, highly sensitive, and effective approach. The future of diagnosis will rely on the development of point-of-care devices, which can be used at the site of need, resource-restricted settings, and provides affordability. This review describes various analytical methods for the detection of HCMV emphasizing biosensing methods

Biological Function of Exosomes as Diagnostic Markers and Therapeutic Delivery Vehicles in Carcinogenesis and Infectious Diseases

Exosomes are nano-sized vesicles that are formed during inward budding of multivesicular bodies and the maturation of endosomes. They are secreted by almost all cell types under normal, pathological, and physiological conditions. They are found in mostly all biological fluids, such as breast milk, blood, urine, and semen. Exosomes are involved in cell-to-cell communication through the biological transfer of lipids, proteins, DNAs, RNAs, mRNAs, and miRNAs. Exosomes are enriched in tetraspanins, enzymes, heat shock proteins, and membrane trafficking proteins. There are numerous techniques that are used to isolate, purify, and characterize exosomes from biofluids. Isolation/purification techniques include ultracentrifugation, filtration, sucrose density gradient centrifugation, etc. Characterization techniques include flow cytometry, electron microscopy, NanoSight tracking analysis, Western blot, etc. These techniques are often used to help principal investigators understand the properties and biological functions of exosomes. However, some of these techniques can be very complicated and challenging, resulting in various drawbacks. Exosomes can be used as potential carriers for therapeutics. Thus, they can serve as biomarkers to diagnosis various diseases that are associated with cancer, genetics, viruses, bacteria, parasites, etc. Therefore, with advances in science and technology, many innovative techniques have been established to exploit the biological properties of exosomes