Shiga Toxin Detection Methods : A Short Review

The Shiga toxins comprise a family of related protein toxins secreted by certain types of bacteria. Shigella dysenteriae, some strain of Escherichia coli and other bacterias can express toxins which caused serious complication during the infection. Shiga toxin and the closely related Shiga-like toxins represent a group of very similar cytotoxins that may play an important role in diarrheal disease and hemolytic-uremic syndrome. The outbreaks caused by this toxin raised serious public health crisis and caused economic losses. These toxins have the same biologic activities and according to recent studies also share the same binding receptor, globotriosyl ceramide (Gb3). Rapid detection of food contamination is therefore relevant for the containment of food-borne pathogens. The conventional methods to detect pathogens, such as microbiological and biochemical identification are time-consuming and laborious. The immunological or nucleic acid-based techniques require extensive sample preparation and are not amenable to miniaturization for on-site detection. In the present are necessary of techniques of rapid identification, simple and sensitive which can be employed in the countryside with minimally-sophisticated instrumentation. Biosensors have shown tremendous promise to overcome these limitations and are being aggressively studied to provide rapid, reliable and sensitive detection platforms for such applications.Comment: 16 pages, 2 figure

Classification of analytics, sensorics, and bioanalytics with polyelectrolyte multilayer capsules

Polyelectrolyte multilayer (PEM) capsules, constructed by LbL (layer-by-layer)-adsorbing polymers on sacrificial templates, have become important carriers due to multifunctionality of materials adsorbed on their surface or encapsulated into their interior. They have been also been used broadly used as analytical tools. Chronologically and traditionally, chemical analytics has been developed first, which has long been synonymous with all analytics. But it is not the only development. To the best of our knowledge, a summary of all advances including their classification is not available to date. Here, we classify analytics, sensorics, and biosensorics functionalities implemented with polyelectrolyte multilayer capsules and coated particles according to the respective stimuli and application areas. In this classification, three distinct categories are identified: (I) chemical analytics (pH; K+, Na+, and Pb2+ ion; oxygen; and hydrogen peroxide sensors and chemical sensing with surface-enhanced Raman scattering (SERS)); (II) physical sensorics (temperature, mechanical properties and forces, and osmotic pressure); and (III) biosensorics and bioanalytics (fluorescence, glucose, urea, and protease biosensing and theranostics). In addition to this classification, we discuss also principles of detection using the above-mentioned stimuli. These application areas are expected to grow further, but the classification provided here should help (a) to realize the wealth of already available analytical and bioanalytical tools developed with capsules using inputs of chemical, physical, and biological stimuli and (b) to position future developments in their respective fields according to employed stimuli and application areas

The future of laboratory medicine - A 2014 perspective.

Predicting the future is a difficult task. Not surprisingly, there are many examples and assumptions that have proved to be wrong. This review surveys the many predictions, beginning in 1887, about the future of laboratory medicine and its sub-specialties such as clinical chemistry and molecular pathology. It provides a commentary on the accuracy of the predictions and offers opinions on emerging technologies, economic factors and social developments that may play a role in shaping the future of laboratory medicine

NANOSCIENCE IN DIAGNOSTICS: A SHORT REVIEW

Nanoscience is at the leading edge of the rapidly developing field of nanotechnology. Nanosciences and nanotechnology are transforming a wide array of products and services that have the potential to enhance the practice of medicine and improve public health. Several areas of medical care are already benefiting from the advantages that nanotechnology can offer. Applications of nanoscience are in biotechnology, medicine, pharmaceuticals, physics, material science and also electronics. Nanotechnology extends the limits of molecular diagnostics to the nanoscale. Nanotechnology on a chip is one more dimension of microfluidic/lab on a chip technology. We still suffer serious and complex illnesses like cancer, cardiovascular diseases, multiple sclerosis, Alzheimer’s and Parkinson’s disease, and diabetes as well as different kinds of serious inflammatory or infectious diseases (e.g. HIV). It is of extreme importance to face these diseases with appropriate means. The interplay between nanoscience and biomedicine is the hallmark of current scientific research worldwide. The use of nanoscience may open new vistas of improving the effectiveness and efficiency of medical diagnosis and therapeutics, so called nanomedicine. An appealing example is the use of quantum dots as fluorescent labels. Despite recent progress in the treatment of cancer, the majority of cases are still diagnosed only after tumors metastasize, leaving the patient with a grim prognosis. Nanotechnology is in a unique position to transform cancer diagnostics and to produce a new generation of biosensors and medical imaging techniques with higher sensitivity and precision of recognition. Novel nanotechnologies can complement and augment existing genomic and proteomic techniques employed to analyze variations across different tumor types, thus offering the potential to distinguish between normal and malignant cells. This brief review tries to reiterate the most contemporary developments in the field of applied nanoscience, particularly in their relevance in diagnosis of various diseases and discuss their future prospects

Fully Integrated Biochip Platforms for Advanced Healthcare

Recent advances in microelectronics and biosensors are enabling developments of innovative biochips for advanced healthcare by providing fully integrated platforms for continuous monitoring of a large set of human disease biomarkers. Continuous monitoring of several human metabolites can be addressed by using fully integrated and minimally invasive devices located in the sub-cutis, typically in the peritoneal region. This extends the techniques of continuous monitoring of glucose currently being pursued with diabetic patients. However, several issues have to be considered in order to succeed in developing fully integrated and minimally invasive implantable devices. These innovative devices require a high-degree of integration, minimal invasive surgery, long-term biocompatibility, security and privacy in data transmission, high reliability, high reproducibility, high specificity, low detection limit and high sensitivity. Recent advances in the field have already proposed possible solutions for several of these issues. The aim of the present paper is to present a broad spectrum of recent results and to propose future directions of development in order to obtain fully implantable systems for the continuous monitoring of the human metabolism in advanced healthcare applications

Remotely triggered scaffolds for controlled release of pharmaceuticals

Fe3O4-Au hybrid nanoparticles (HNPs) have shown increasing potential for biomedical applications such as image guided stimuli responsive drug delivery. Incorporation of the unique properties of HNPs into thermally responsive scaffolds holds great potential for future biomedical applications. Here we successfully fabricated smart scaffolds based on thermo-responsive poly(N-isopropylacrylamide) (pNiPAM). Nanoparticles providing localized trigger of heating when irradiated with a short laser burst were found to give rise to remote control of bulk polymer shrinkage. Gold-coated iron oxide nanoparticles were synthesized using wet chemical precipitation methods followed by electrochemical coating. After subsequent functionalization of particles with allyl methyl sulfide, mercaptodecane, cysteamine and poly(ethylene glycol) thiol to enhance stability, detailed biological safety was determined using live/dead staining and cell membrane integrity studies through lactate dehydrogenase (LDH) quantification. The PEG coated HNPs did not show significant cytotoxic effect or adverse cellular response on exposure to 7F2 cells (p < 0.05) and were carried forward for scaffold incorporation. The pNiPAM-HNP composite scaffolds were investigated for their potential as thermally triggered systems using a Q-switched Nd:YAG laser. These studies show that incorporation of HNPs resulted in scaffold deformation after very short irradiation times (seconds) due to internal structural heating. Our data highlights the potential of these hybrid-scaffold constructs for exploitation in drug delivery, using methylene blue as a model drug being released during remote structural change of the scaffold

A new landscape of host–protozoa interactions involving the extracellular vesicles world

This version is free to view and download for private research and study only. Not for re-distribution, re-sale or use in derivative works. © Cambridge University Press 2018Extracellular vesicles (EVs) are released by a wide number of cells including blood cells, immune system cells, tumour cells, adult and embryonic stem cells. EVs are a heterogeneous group of vesicles (~30–1000 nm) including microvesicles and exosomes. The physiological release of EVs represents a normal state of the cell, raising a metabolic equilibrium between catabolic and anabolic processes. Moreover, when the cells are submitted to stress with different inducers or in pathological situations (malignancies, chronic diseases, infectious diseases.), they respond with an intense and dynamic release of EVs. The EVs released from stimulated cells vs those that are released constitutively may themselves differ, both physically and in their cargo. EVs contain protein, lipids, nucleic acids and biomolecules that can alter cell phenotypes or modulate neighbouring cells. In this review, we have summarized findings involving EVs in certain protozoan diseases. We have commented on strategies to study the communicative roles of EVs during host–pathogen interaction and hypothesized on the use of EVs for diagnostic, preventative and therapeutic purposes in infectious diseases. This kind of communication could modulate the innate immune system and reformulate concepts in parasitism. Moreover, the information provided within EVs could produce alternatives in translational medicine.Peer reviewedFinal Accepted Versio

Present and future of surface-enhanced Raman scattering

The discovery of the enhancement of Raman scattering by molecules adsorbed on nanostructured metal surfaces is a landmark in the history of spectroscopic and analytical techniques. Significant experimental and theoretical effort has been directed toward understanding the surface-enhanced Raman scattering (SERS) effect and demonstrating its potential in various types of ultrasensitive sensing applications in a wide variety of fields. In the 45 years since its discovery, SERS has blossomed into a rich area of research and technology, but additional efforts are still needed before it can be routinely used analytically and in commercial products. In this Review, prominent authors from around the world joined together to summarize the state of the art in understanding and using SERS and to predict what can be expected in the near future in terms of research, applications, and technological development. This Review is dedicated to SERS pioneer and our coauthor, the late Prof. Richard Van Duyne, whom we lost during the preparation of this article