Using drinking data and pharmacokinetic modeling to calibrate transport model and blind deconvolution based data analysis software for transdermal alcohol biosensors

Alcohol researchers/clinicians have two ways to collect subject /patient field data, standard-drink self-report and the breath analyzer, neither of which is passive or accurate because active subject participation is required. Transdermal alcohol sensors have been developed to measure transdermal alcohol concentration (TAC), but they are used primarily as abstinence monitors because converting TAC into more meaningful blood/breath alcohol concentration (BAC/BrAC) is difficult. In this paper, BAC/BrAC is estimated from TAC by first calibrating forward distributed parameter-based convolution models for ethanol transport from the blood through the skin using patient-collected drinking data for a single drinking episode and a nonlinear pharmacokinetic metabolic absorption/elimination model to estimate BAC. TAC and estimated BAC are then used to fit the forward convolution filter. Nonlinear least squares with adjoint-based gradient computation are used to fit both models. Calibration results are compared with those obtained using BAC/BrAC from alcohol challenges and from standard, linear, metabolic absorption, and zero order kinetics-based elimination models, by considering peak BAC, time of peak, and area under the BAC curve. Our models (with population parameters) could be included in a smart phone app that makes it convenient for the subject/patient to enter drinking data for a single episode in the field.

Bringing next-generation diagnostics to the clinic through synthetic biology

The promise for real precision medicine is contingent on innovative technological solutions to diagnosis and therapy. In the post‐genomic era, rational and systematic approaches to biological design could provide new ways to dynamically probe, monitor, and interface human pathophysiology. Emerging as a mature field increasingly transitioning to the clinics, synthetic biology integrates engineering principles to build sensors, control circuits, and actuators within the biological substrate according to clinical specifications. A particularly tantalizing goal is to develop novel versatile, programmable and autonomous diagnostic devices intertwined with therapy and personalized for the patient to get closest, finest, and most comprehensive diagnostic information and medical procedures. Here, we discuss how synthetic biology could be preparing the future of medicine, supporting and speeding up the development of diagnostics with novel capabilities to bring direct improvement from the clinical laboratory to the patient, while addressing healthcare evolution and global health concerns.

Measurement of Electrical Skin Impedance of Dermal-Visceral Zones as a Diagnostic Tool for Disorders of the Immune System

Among complementary medicine approaches, diagnostic screening tools based on neuroreflexology have been recently developed. Such techniques are based on the rationale that measurement of electrical impedance of specific dermal zones might reflect the occurrence of pathological states in the corresponding internal organs or systems. Our objective was to evaluate the reliability of a neuroreflexology-based diagnostic test in diagnosing immune-mediated diseases in a blinded single centre study. Seventy-eight patients with immune-mediated diseases (38 patients with autoimmune diseases (AD), and 40 allergic patients) were included in the study. Thirty age and sex matched healthy subjects were also evaluated as a control group. All the patients and subjects underwent conventional medical history and physical examination. We evaluated a device manufactured by Medex Screen Ltd (Arad, Israel). The Medex Test analysis was carried out by a second physician who was blinded to the previous diagnosis. A high correlation between the formal clinical diagnosis and the results of the measurement of electrical skin impedance was reported, with a specificity of 93.3% and a sensitivity of 81.2%. Both sensitivity and specificity dropped when analysing the autoimmune and the allergic group separately, but remained significant for the autoimmune diseases. Degree of activity of the allergic disorders, or specific treatment, did not affect the diagnostic properties of the described device. The Medex Test neurophysiology based technique has the potential to serve as a diagnostic tool for immune based pathologies. Future studies will define this tool place in routine evaluation and potential screening ability.

Some Effects of a Topical Collagen-Based Matrix on the Microcirculation and Wound Healing in Patients With Chronic Venous Leg Ulcers: Preliminary Observations

Themicrocirculation of the wound bed is a key parameter for improving granulation tissue formation and, hence, wound healing. The aim of this study was to determine whether a wound dressing comprising collagen/oxidized regenerated cellulose has effects over a short term on wound healing. Wounds were evaluated using a clinical wound score; pain associated with wounds was measured using a visual analogue scale. Wound microcirculation was evaluated using a technique based on noncontact remission spectroscopy. A prospective trial was performed in 40 patients with chronic venous leg ulcers (mean age 74 years; range, 43-93 years; 25 females and 15 males). Patients in group A were treated with PROMOGRAN® Matrix (Johnson& Johnson, New Brunswick, NJ) combined with “good” ulcer care for 2 weeks. Control group B consisted of 10 patientswho received only good ulcer care. The authors measured a favorable clinical response in 76.9% (group A) versus 66.7% (group B). Themean reduction of ulcer area was statistically significant in group A (P < .05). The wound score improved in group A from 2.28 ± 1.24 (before treatment) increasing to 3.72 ± 1.57 (after 1 week; P < .00023) and 4.92 ± 1.68 (after 2 weeks; P < .000027). In group B, the score improved from 1.44 ± 1.33 (before treatment) to 3.22 ± 1.30 (after 1 week; P < .0077). The mean visual analogue pain score before treatment was 8.72 (group A) and 7.88 (group B) (ns,P > .05). After 1 week of treatment, the score dropped to 5.76 (group A) and 6.66 (group B). In the second week, group A patients had a mean pain score of 3.84 compared with the pain score before treatment (P < .05). After 1 week of treatment, in group A there was a decrease in remission spectroscopy, which is considered to reflect an improvement in microcirculation.

An Integrated Circuit for Chip-Based Analysis of Enzyme Kinetics and Metabolite Quantification

We have created a novel chip-based diagnostic tools based upon quantification of metabolites using enzymes specific for their chemical conversion. Using this device we show for the first time that a solid-state circuit can be used to measure enzyme kinetics and calculate the Michaelis-Menten constant. Substrate concentration dependency of enzyme reaction rates is central to this aim. Ion-sensitive field effect transistors (ISFET) are excellent transducers for biosensing applications that are reliant upon enzyme assays, especially since they can be fabricated using mainstream microelectronics technology to ensure low unit cost, mass-manufacture, scaling to make many sensors and straightforward miniaturisation for use in point-of-care devices. Here, we describe an integrated ISFET array comprising 2(16) sensors. The device was fabricated with a complementary metal oxide semiconductor (CMOS) process. Unlike traditional CMOS ISFET sensors that use the Si3N4 passivation of the foundry for ion detection, the device reported here was processed with a layer of Ta2O5 that increased the detection sensitivity to 45 mV/pH unit at the sensor readout. The drift was reduced to 0.8 mV/hour with a linear pH response between pH 2-12. A high-speed instrumentation system capable of acquiring nearly 500 fps was developed to stream out the data. The device was then used to measure glucose concentration through the activity of hexokinase in the range of 0.05 mM-231 mM, encompassing glucose's physiological range in blood. Localised and temporal enzyme kinetics of hexokinase was studied in detail. These results present a roadmap towards a viable personal metabolome machine.

Translating diagnostic assays from the laboratory to the clinic: analytical and clinical metrics for device development and evaluation

As lab-on-a-chip health diagnostic technologies mature, there is a push to translate them from the laboratory to the clinic. For these diagnostics to achieve maximum impact on patient care, scientists and engineers developing the tests should understand the analytical and clinical statistical metrics that determine the efficacy of the test. Appreciating and using these metrics will benefit test developers by providing consistent measures to evaluate analytical and clinical test performance, as well as guide the design of tests that will most benefit clinicians and patients. This paper is broken into four sections that discuss metrics related to general stages of development including: (1) laboratory assay development (analytical sensitivity, limit of detection, analytical selectivity, and trueness/precision), (2) pre-clinical development (diagnostic sensitivity, diagnostic specificity, clinical cutoffs, and receiver-operator curves), (3) clinical use (prevalence, predictive values, and likelihood ratios), and (4) case studies from existing clinical data for tests relevant to the lab-on-a-chip community (HIV, group A strep, and chlamydia). Each section contains definitions of recommended statistical measures, as well as examples demonstrating the importance of these metrics at various stages of the development process. Increasing the use of these metrics in lab-on-a-chip research will improve the rigor of diagnostic performance reporting and provide a better understanding of how to design tests that will ultimately meet clinical needs.

Analytical applications of MIPs in diagnostic assays: future perspectives

Many efforts have been made to produce artificial materials with biomimetic properties for applications in binding assays. Among these efforts, the technique of molecular imprinting has received much attention because of the high selectivity obtainable for molecules of interest, robustness of the produced polymers, simple and short synthesis, and excellent cost efficiency. In this review, progress in the field of molecularly imprinted sorbent assays is discussed-with a focus on work conducted from 2005 to date.

Precision chemical heating for diagnostic devices

Decoupling nucleic acid amplification assays from infrastructure requirements such as grid electricity is critical for providing effective diagnosis and treatment at the point of care in low-resource settings. Here, we outline a complete strategy for the design of electricity-free precision heaters compatible with medical diagnostic applications requiring isothermal conditions, including nucleic acid amplification and lysis. Low-cost, highly energy dense components with better end-of-life disposal options than conventional batteries are proposed as an alternative to conventional heating methods to satisfy the unique needs of point of care use.

Technological advances in bovine mastitis diagnosis: an overview

Bovine mastitis is an economic burden for dairy farmers and preventive control measures are crucial for the sustainability of any dairy business. The identification of etiological agents is necessary in controlling the disease, reducing risk of chronic infections and targeting antimicrobial therapy. The suitability of a detection method for routine diagnosis depends on several factors, including specificity, sensitivity, cost, time in producing results, and suitability for large-scale sampling of milk. This article focuses on current methodologies for identification of mastitis pathogens and for detection of inflammation, as well as the advantages and disadvantages of different methods. Emerging technologies, such as transcriptome and proteome analyses and nano- and microfabrication of portable devices, offer promising, sensitive methods for advanced detection of mastitis pathogens and biomarkers of inflammation. The demand for alternative, fast, and reliable diagnostic procedures is rising as farms become bigger. Several examples of technological and scientific advances are summarized which have given rise to more sensitive, reliable and faster diagnostic results.

[Consanguinity between meridian theory and Bianque's pulse theory]

The integral meridian theory is composed of five parts, including meridian course, syndrome, diagnostic method, treating principle and treatment, and the core of it is meridian syndrome. It has been proved by multiple evidences that the meridian syndrome induced by the pathological change in meridian and the death syndrome of pulse penetrating or attaching to the syndrome are all originated from Bianque' s facial color and pulse diagnosis. And regarding the pulse syndrome,there are many different interpretations based on the theory of yin-yang in four seasons before the Han Dynasty. The emerging of Biaoben diagnostic method in Bianque's pulse method and its extensive clinical application promote a new theoretic interpretation the connection of meridians interpreting pulse syndrome directly. Besides, along with the new development of blood-pulse theory of Bianque's medicine, the revolution on meridian theory is aroused as well its theoretical paradigm turning from "tree" type to "ring" type. In other words, Bianque's medicine not only gives birth to meridian theory, but also decides its final development.

[Analysis on renving and cunkou pulse diagnostic methods in Internal Classic and Pulse Classic]

Renying and cunkou pulse diagnostic methods have been recorded in Neijing Unternal Classic) and Maijing (Pulse Classic) and these two pulse diagnostic methods are very different. Through the analysis and inference on the relevant statements in Internal Classic and Pulse Classic, as well as those of medical scholars in later generations, it is discovered that the pulse of excess type, the pulse of deficiency type, the tense pulse, the regular missed-beat pulse, etc. could be detected and be used to judge the disorders of meridians and zangfu organs by the comparison between the pulse of excess type and the pulse of deficiency type with renying and cunkou pulse diagnostic methods recorded in Internal Classic. The substance of renying and cunkou pulse diagnostic methods in Pulse Classic is consistent with the methods in later generations, meaning that they can be applied to judge the disorders of meridians and zangfu organs through detecting the excess or the deficiency in every region of cun, guan and chi.

[Telemedicine in your suitcase: useful tools for the traveler]

In our digital age, telemedicine becomes, under various forms, a useful companion for the traveler, providing access to up-to-date information about health and security risks, remote consultation of specialists to ascertain a diagnosis of select an appropriate treatment, connection to similar patients in order to obtain contextualized advice, biomedical sensors and other monitoring and diagnostic portable tools, as well as transportable electronic health records enabling continuity of care and mobility. Commercial telemedicine services are being developed specifically for travelers, most of which are using mobile phones as the main device, which thus becomes a real telestethoscope.

New system for tracking a device for diagnosing scalp skin

In scalp skin examinations, it is difficult to find a previously treated region on a patient's scalp through images captured by a camera attached to a diagnostic device because the zoom lens on camera has a small field of view. Thus, doctors manually record the region on a chart or manually mark the region. However, this process is slow and inconveniences the patient. Thus, we propose a new system for tracking the diagnostic device for the scalp skin of patients. Our research is novel in four ways. First, our proposed system consists of two cameras to capture the face and the diagnostic device. Second, the user can easily set the position of camera to capture the diagnostic device by manually moving a frame to which the camera is attached. Third, the position of patient's nostrils and corners of the eyes are detected to align the position of his/her head more accurately with the recorded position from previous sessions. Fourth, the position of the diagnostic device is continuously tracked during the examination through images that help detect the position of the color marker attached to the device. Experimental results show that our system has a higher performance than conventional method.

Efficacy and complications of computed tomography-guided hook wire localization

BACKGROUND

Video-assisted thoracic surgery offers a minimally invasive method for diagnosing and treating small pulmonary lesions, although the localization of these lesions is sometimes problematic. Various localization methods have been reported but few studies have described their efficacy and adverse events.

METHODS

We performed computed tomography (CT)-guided localization using a hook wire in 417 patients with 500 lesions treated between January 2006 and December 2010.

RESULTS

We located 178 lesions with a ground-glass opacity component and 322 solid lesions. The solid lesions had smaller tumor diameters and were located further from the pleura. Tumor depth to size ratio was 0.9 ± 0.9 for the lesions with a ground-glass opacity component and 1.8 ± 1.5 for the solid lesions (p < 0.001). Pneumothorax requiring aspiration was observed in 4.6% patients, and hemoptysis and pulmonary hematoma was observed in 10.3%. Systemic air embolism with no sequelae and spontaneous resolution occurred in a patient (0.24%). The morbidity rate was 15.1%. Male patients, patients who had undergone multiple localization, and heavy smokers were at a higher risk of pneumothorax requiring aspiration. Insertion distance more than 25 mm was a risk factor for hemoptysis and pulmonary hematoma (p < 0.001). Procedure duration per lesion was 14 ± 5 minutes. Dislodgement occurred in 2 patients (0.4%).

CONCLUSIONS

The safety, reliability, and convenience of CT-guided hook wire localization are acceptable. Localization for lesions with a ground-glass opacity component may be performed when the lesions are relatively large and shallow. Insertion distances greater than 25 mm are associated with a risk of pulmonary hematoma and hemoptysis.

Health-related quality of life assessment after antiretroviral therapy: a review of the literature

Antiretroviral (ARV) treatment for HIV infection has resulted in significant improvement in immunologic and virologic parameters, as well as a reduction in AIDS-defining illnesses and death. Over 25 medications are approved for use, usually in combination regimens of three or four ARVs. Several ARVs are now available as combinatorial products, which have been associated with better adherence. However, while ARV therapy has prolonged life, ARVs also pose a challenge for quality of life as they can cause significant side effects in addition to the potential for drug toxicity and interaction. Given the many complications, side effects and symptoms of HIV/AIDS in addition to associated medical and psychiatric co-morbidities, the need to understand and assess how these interactions may affect health-related quality of life (HRQOL) has grown. Numerous instruments (some validated, others not) are available and have been applied to understanding how ARV treatment affects HRQOL in those with HIV infection, both in clinical trials and clinical practice. In general, ARV treatment improves HRQOL, but this is dependent on the population being studied, the HRQOL instrument being used and the timeframe during which HRQOL has been studied. This article provides a review of the literature on quality of-life assessment as it relates to ARV treatment in developed countries and briefly reviews the HRQOL instruments used, how they have been applied to ARV utilization, and where future research should be applied in HRQOL assessment and HIV infection.

Rapid diagnosis of Mycobacterium tuberculosis with Truenat MTB: a near-care approach

Background

Control of the global Tuberculosis (TB) burden is hindered by the lack of a simple and effective diagnostic test that can be utilized in resource-limited settings.

Methods

We evaluated the performance of Truenat MTB™, a chip-based nucleic acid amplification test in the detection of Mycobacterium tuberculosis (MTB) in clinical sputum specimens from 226 patients with suspected pulmonary tuberculosis (TB). The test involved sputum processing using Trueprep-MAG™ (nanoparticle-based protocol run on a battery-operated device) and real-time PCR performed on the Truelab Uno™ analyzer (handheld, battery-operated thermal cycler). Specimens were also examined for presence of MTB using smear microscopy, liquid culture and an in-house nested PCR protocol. Results were assessed in comparison to a composite reference standard (CRS) consisting of smear and culture results, clinical treatment and follow-up, and radiology findings.

Results

Based on the CRS, 191 patients had “Clinical-TB” (Definite and Probable-TB). Of which 154 patients are already on treatment, and 37 were treatment naïve cases. Remaining 35 were confirmed “Non-TB” cases which are treatment naïve cases. The Truenat MTB test was found to have sensitivity and specificity of 91.1% (CI: 86.1–94.7) and 100% (CI: 90.0–100) respectively, in comparison to 90.58% (CI: 85.5–94.3) and 91.43% (CI: 76.9–98.2) respectively for the in-house nested PCR protocol.

Conclusion

This preliminary study shows that the Truenat MTB test allows detection of TB in approximately one hour and can be utilized in near-care settings to provide quick and accurate diagnosis.

Overview of the microfluidic diagnostics commercial landscape

Since its birth in the late 1980s, the field of microfluidics has continued to mature, with a growing number of companies pursuing diagnostic applications. In 2009 the worldwide in vitro diagnostics market was estimated at >$40 billion USD, and microfluidic diagnostics are poised to reap a significant part of this market across a range of areas including laboratory diagnostics, point-of-care diagnostics, cancer diagnostics, and others. The potential economic advantages of microfluidics are numerous and compelling: lower reagent and/or sample volumes, lower equipment costs, improved portability, increased automation, and increased measurement speed. All of these factors may help put more information in the hands of doctors and patients sooner, enabling earlier disease detection and more tailored, effective treatments. This chapter reviews the microfluidic diagnostics commercial landscape and discusses potential commercialization challenges and opportunities.

Introduction to in vitro diagnostic device regulatory requirements

A common application for microfluidics can be found in medical devices where the advantages of small volume measuring equipment can be exploited for In Vitro Diagnostics. This chapter focuses on the US and the EU regulations, explaining the broad landscape and regulatory pathways of each market.

Three-dimensional, paper-based microfluidic devices containing internal timers for running time-based diagnostic assays

This chapter describes a method for fabricating three-dimensional (3D), paper-based microfluidic devices that contain internal timers for running quantitative, time-based assays. The method involves patterning microfluidic channels into paper, and cutting double-sided adhesive tape into defined patterns. Patterned paper and tape are assembled layer by layer to create 3D microfluidic devices that are capable of distributing microliter volumes of a sample into multiple regions on a device for conducting multiple assays simultaneously. Paraffin wax is incorporated into defined regions within the device to provide control over the distribution rate of a sample, and food coloring is included in defined regions within the device to provide an unambiguous readout when the sample has reached the bottom of the device (this latter feature is the endpoint of the timer).