In vitro diagnostic technology

Reproductive failure in humans is a very important social and economic problem, because nowadays women decide to conceive later in life and delay motherhood. Unfortunately, with increasing age they have less chance for natural fertilization and maintenance of pregnancy. Many of them need assisted reproductive technology. Approximately 10% of women after in vitro fertilization-embryo transfers experience recurrent implantation failure (RIF). Multiple factors may contribute to RIF, including oocyte and sperm quality, parental chromosomal anomalies, genetic or metabolic abnormalities of the embryo, poor uterine receptivity, immunological disturbances in the implantation site, and some gynecologic pathologies such as endometriosis, uterine fibroids, hydrosalpinx and endometrial polyps...

Clostridium sordellii is a lethal pathogen for both animals and humans. Severe capillary leakage, toxic shock syndrome, and an extreme leukemoid reaction (LR), are hallmark features of C. sordellii infections and contribute to its high mortality rate. Here we report the discovery of a previously unknown and uncharacterized metalloproteinase of C. sordellii (referred as Mcs1) that cleaves human vascular cell adhesion molecule (VCAM)-1 in vitro, an adhesion molecule critical to hematopoietic precursor retention and leukocyte diapedesis...

Objectives: Magnesium sulfate (MgSO 4 ) was recently reported as an alternative in vitro anticoagulant in pseudo-thrombocytopenia. Its suitability as an anticoagulant for the determination of reliable platelet parameters is the subject of this study. Methods: Platelet count and mean platelet volume were measured in blood samples anticoagulated with EDTA and MgSO 4 and compared. The platelet parameters were determined by impedance (XE 5000 [Sysmex, Norderstedt, Germany]; DxH 800 [Beckman-Coulter, Krefeld, Germany]) and laser light-scatter technology (Advia 120 [Siemens Healthcare Diagnostics, Eschborn, Germany])...

The development of rapid and sensitive point-of-test devices for on-site monitoring of heavy-metal contamination has great scientific and technological importance. However, developing fast, inexpensive, and sensitive microarray sensors to achieve such a goal remains challenging. In this work, we present a DNA-nanostructured microarray (DNM) with a tubular three-dimensional sensing surface and an ordered nanotopography. This microarray enables enhanced molecular interaction toward the rapid and sensitive multiplex detection of heavy-metal ions...

BACKGROUND: Multi drug resistant tuberculosis (MDR-TB) poses formidable challenges to TB control due to its complex diagnostic and treatment challenges and often associated with a high rate of mortality. Accurate and rapid detection of MDR-TB is critical for timely initiation of treatment. Line Probe Assay (LPA) is a qualitative in vitro diagnostic test based on DNA-STRIP technology for the identification of the M. tuberculosis complex and its resistance to rifampicin (RMP) and/or isoniazid (INH)...

BACKGROUND: The adoption of recently created protocols introduces Mohs laboratories to the principles of immunohistochemistry (IHC) performance validation and clinical laboratory regulations that are unique to these evolving technologies. OBJECTIVE: To review Food and Drug Administration (FDA) IHC reagent classifications, IHC validation protocols, and quality assurance (QA) procedures and documentation needed in conjunction with IHC test guidelines. METHODS: A focused review of IHC reagent classifications and guidelines in clinical testing laboratories was conducted using PubMed and FDA source documents...

Low-dose radiation is widely used across the world for the diagnosis of many diseases by means of a variety of imaging technologies. However, the harmful effects of exposure to low-dose radiation during medical examination remain controversial. The authors studied the effects of medical diagnostic low-dose x rays (i.e., 0.03, 0.05, or 0.1 mGy) after an in vitro exposure of human lymphocytes. Cells with no irradiation served as the non-irradiated control group. Three biological indicators were used to determine the effects of medical diagnostic low-dose x rays at 4, 8, 24, 48, and 72 h post-irradiation...

Inspired by theranostic technologies, we electrostatically loaded proteinaceous microbubbles (MBs) with a model drug, doxorubicin (Dox) to couple their utilizations in diagnostic imaging with drug loading. A temperature-sensitive polymer, poly(N-isopropylacrylamide-block-acrylic acid) (poly(NIPAM-b-AAc)) was used to encapsulate the Dox-loaded MBs to prevent premature release and to control the Dox release thermally. An LCST of 39°C, slightly higher than normal body temperatures, enables the release of Dox through a conformational change of the polymer shell upon moderate heating...

Some cases of fungal infection remained undiagnosed, especially when the pathogens are uncommon, require specific conditions for in vitro growth, or when several microbial species are present in the specimen. Ultra-Deep Sequencing (UDS) could be considered as a precise tool in the identification of involved pathogens in order to upgrade patient treatment. In this study, we report the implementation of UDS technology in medical laboratory during the follow-up of an atypical fungal infection case. Thanks to UDS technology, we document the first case of gastro-intestinal basidiobolomycosis (GIB) due to Basidiobolus meristosporus...

PURPOSE OF REVIEW: The purpose of this review is to summarize recent research regarding the diagnosis of allergic rashes and to suggest future directions for the promotion of accurate diagnosis and endotype specification. RECENT FINDINGS: Multiple cohort studies demonstrate that with appropriate clinical evaluation, drug allergy labels can be removed in up to 90% of cases. Genetic tests can predict severe adverse cutaneous drug reactions in some cases and in vitro tests are being sought to identify causative drugs in others...

Aptamers are short DNA or RNA oligonucleotides specialized in the specific and efficient binding to a target molecule. They are obtained by in vitro selection or evolution processes. It was in 1990 that two independent research groups described the bases of a new in vitro technology for the identification of RNA molecules able to specifically bind to a target [1,2]. Tuerk and Gold established the principals of the in vitro selection process that was named SELEX (Systematic Evolution of Ligands by Exponential enrichment), which is based on iterative cycles of binding, partitioning, and amplification of oligonucleotides from a pool of variant sequences [2]...

STUDY OBJECTIVE: This study aimed to review surgical management and clinical outcomes of patients with heterotopic pregnancy (HP) who underwent in vitro fertilization and embryo transfer (IVF-ET) and surgical treatment at the Assisted Reproductive Technology Center of Peking University Third Hospital from January 2010 to December 2015. DESIGN: We retrospectively analyzed 56 patients' general characteristics, diagnostic features, surgical management, and clinical outcomes according to medical records and follow-up telephone interviews...

Aptamers are short nucleic acids that interact with a variety of targets with high affinity and specificity. They have been shown to inhibit biological functions of cognate target proteins, and they are identifiable by an in vitro selection process, also termed SELEX (Systematic Evolution of Ligands by EXponential enrichment). Being nucleic acids, aptamers can be synthesized chemically or enzymatically. The latter renders RNA aptamers compatible with the cell's own transcription machinery and, thus, expressable inside cells...

Dengue is a mosquito-borne disease caused by four genetically and serologically related viruses that affect several millions of people. Envelope domain III (EDIII) of the viral envelope protein contains dengue virus (DENV) type-specific and DENV complex-reactive antigenic sites. Here, we describe the expression in Escherichia coli, the refolding and bio-structural analysis of envelope domain III of the four dengue serotypes as a tetravalent dengue protein (EDIIIT2), generating an attractive diagnostic candidate...

Endometrial polyps are frequently seen in subfertile women, and there is some evidence suggesting a detrimental effect on fertility. How polyps contribute to subfertility and pregnancy loss is uncertain and possible mechanisms are poorly understood. It may be related to mechanical interference with sperm transport, embryo implantation or through intrauterine inflammation or altered production of endometrial receptivity factors. Different diagnostic modalities such as two- or three-dimensional transvaginal ultrasound, saline infusion sonography or hysteroscopy are commonly used to evaluate endometrial polyps with good detection rates...

Magnetic nanoparticles have been one of the most attractive nanomaterials for various biomedical applications including magnetic resonance imaging (MRI), diagnostic contrast enhancement, magnetic cell separation, and targeted drug delivery. Three-dimensional (3-D) fibrous scaffolds have broad application prospects in the biomedical field, such as drug delivery and tissue engineering. In this work, a novel three-dimensional composite membrane composed of the tri-block copolymer poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) (PCL-PEG-PCL, PCEC) and magnetic iron oxide nanoparticles (Fe3O4 NPs) were fabricated using electrospinning technology...

Identification errors have emerged as a critical issue in health care, as testified by the ample scientific literature on this argument. Despite available evidence suggesting that the frequency of misidentification in vitro laboratory diagnostic testing may be relatively low compared to that of other laboratory errors (i.e., usually comprised between 0.01 and 0.1% of all specimens received), the potential adverse consequences remain particularly worrying, wherein 10-20% of these errors not only would translate into serious harm for the patient, but may also erode considerable human and economic resources, so that the entire healthcare system should be re-engineered to act proactively and limiting the burden of this important problem...

BACKGROUND: SNAP-tag, a self-labeling protein tag, is commonly used for in vitro and in vivo analysis of bound target proteins. We report the first evidence that SNAP-tag could be used for ex vivo detection of enriched biological markers. METHODS: Proof of concept was established for target c-kit receptor, a pathological and diagnostic marker for a variety of cancers. SNAP-tag conjugates with stem-cell factor (SCF) fusion proteins were designed and their binding and specificity was validated in vitro using flow cytometry and immunostaining...

Leprosy is a chronic infectious disease caused by Mycobacterium leprae. Identification of Mycobacterium leprae is difficult in part due to the inability of the leprosy bacillus to grow in vitro. A number of diagnostic methods for leprosy diagnosis have been proposed. Both serological tests and molecular probes have shown certain potential for detection and identification of Mycobacterium leprae in patients. In this study, we have investigated whether Mycobacterium leprae DNA from the nasal secretion of healthy household contacts and the non contacts could be detected through PCR amplification as a method to study the sub clinical infection in a community...

Alternative methods for accurate in vitro assessment of skin and respiratory sensitizers are urgently needed. Sensitization is a complex biological process that cannot be evaluated accurately using single events or biomarkers, since the information content is too restricted in these measurements. On the contrary, if the tremendous information content harbored in DNA/mRNA could be mined, most complex biological processes could be elucidated. Genomic technologies available today, including transcriptional profiling and next generation sequencing, have the power to decipher sensitization, when used in the right context...