Rapid and simultaneous detection of Ureaplasma parvum and Chlamydia trachomatis antibodies based on visual protein microarray using gold nanoparticles and silver enhancement

Ureaplasma infections: update on epidemiology, antimicrobial resistance, and pathogenesis

Human Ureaplasma species are being increasingly recognized as opportunistic pathogens in human genitourinary tract infections, infertility, adverse pregnancy, neonatal morbidities, and other adult invasive infections. Although some general reviews have focused on the detection and clinical manifestations of Ureaplasma spp., the molecular epidemiology, antimicrobial resistance, and pathogenesis of Ureaplasma spp. have not been adequately explained. The purpose of this review is to offer valuable insights into the current understanding and future research perspectives of the molecular epidemiology, antimicrobial resistance, and pathogenesis of human Ureaplasma infections. This review summarizes the conventional culture and detection methods and the latest molecular identification technologies for Ureaplasma spp. We also reviewed the global prevalence and mechanisms of antibiotic resistance for Ureaplasma spp. Aside from regular antibiotics, novel antibiotics with outstanding in vitro antimicrobial activity against Ureaplasma spp. are described. Furthermore, we discussed the pathogenic mechanisms of Ureaplasma spp., including adhesion, proinflammatory effects, cytotoxicity, and immune escape effects, from the perspectives of pathology, related molecules, and genetics.

Recent advances in cellulose-based membranes for their sensing applications

ABSTRACT

In recent years, sensing applications have played a very important role in various fields. As a novel natural material, cellulose-based membranes with many merits can be served as all kinds of sensors. This review summarizes the recent progress of cellulose membranes as sensors, mainly focusing on their preparation processes and sensing properties. In addition, the opportunities and challenges of cellulose membrane-based sensors are also prospected. This review provides some references for the design of cellulose membrane materials for sensing applications in the future.

Nanomedicine applications in women's health: state of the art

State-of-the-art applications of nanomedicine have the potential to revolutionize the diagnosis, prevention, and treatment of a range of conditions and diseases affecting women’s health. In this review, we provide a synopsis of potential applications of nanomedicine in some of the most dominant fields of women’s health: mental health, sexual health, reproductive medicine, oncology, menopause-related conditions and dementia. We explore published studies arising from in vitro and in vivo experiments, and clinical trials where available, to reveal novel and highly promising therapeutic applications of nanomedicine in these fields. For the first time, we summarize the growing body of evidence relating to the use of nanomaterials as experimental tools for the detection, prevention, and treatment of significant diseases and conditions across the life course of a cisgender woman, from puberty to menopause; revealing the far-reaching and desirable theoretical impact of nanomedicine across different medical disciplines. We also present an overview of potential concerns regarding the therapeutic applications of nanomedicine and the factors currently restricting the growth of applied nanomedicine.

Investigating Colorimetric Protein Array Assay Schemes for Detection of Recurrence of Bladder Cancer

A colorimetric microarray for the multiplexed detection of recurrence of bladder cancer including protein markers interleukin-8 (IL8), decorin (DCN), and vascular endothelial growth factor (VEGF) was established to enable easy and cheap read-out by a simple office scanner paving the way for quick therapy monitoring at doctors' offices. The chip is based on the principle of a sandwich immunoassay and was optimized prior to multiplexing using IL8 as a model marker. Six different colorimetric assay formats were evaluated using a detection antibody (dAB) labeled with (I) gold (Au) nanoparticles (NPs), (II) carbon NPs, (III) oxidized carbon NPs, and a biotinylated dAB in combination with (IV) neutravidin-carbon, (V) streptavidin (strp)-gold, and (VI) strp-horseradish peroxidase (HRP). Assay Format (III) worked best for NP-based detection and showed a low background while the enzymatic approach, using 3,3',5,5'-tetramethylbenzidine (TMB) substrate, led to the most intense signals with good reproducibility. Both assay formats showed consistent spot morphology as well as detection limits lower than 15 ng/L IL8 and were thus applied for the multiplexed detection of IL8, DCN, and VEGF in synthetic urine. Colorimetric detection in urine (1:3) yields reaction signals and measurement ranges well comparable with detection in the assay buffer, as well as excellent data reproducibility as indicated by the coefficient of variation (CV 5-9%).

A novel aptasensor for the colorimetric detection of S. typhimurium based on gold nanoparticles

A simple, fast and convenient colorimetric aptasensor was fabricated for the detection of Salmonella typhimurium (S. typhimurium) which was based on the color change effect of gold nanoparticles (GNPs). S. typhimurium is one of the most common causes of food-associated disease. Aptamers with specific recognition toward S. typhimurium was modified to the surface of prepared GNPs. They play a role for the protection of GNPs from aggregation toward high concentrations of NaCl. With the addition of S. typhimurium, aptamers preferably combined to S. typhimurium and the protection effect was broken. With more S. typhimurium, more aptamers detached from GNPs. In such a situation, the exposed GNPs would aggregated to some extent with the addition of NaCl. The color changed from red, purple to blue which could be characterized by UV-Vis spectrophotometer. The absorbance spectra of GNPs redshifted constantly and the intensity ratio of A700/A521 changed regularly. This could be calculated for the basis of quantitative detection of S. typhimurium from 10²cfu/mL to 10⁷cfu/mL. The obtained linear correlation equation was y=0.1946x-0.2800 (R²=0.9939) with a detection limit as low as 56cfu/mL. This method is simple and rapid, results in high sensitivity and specificity, and can be used to detect actual samples.

Molecular and nanotechnologic approaches to etiologic diagnosis of infectious syndromes

Infectious diseases are a major global public health problem. Multiple agents are now recognized to cause indistinguishable illnesses. The term ‘syndrome’ applies to such situations, for which early and rapid diagnosis of the infecting agent would enable prompt and appropriate therapy. Public health physicians would also get timely information on the specific etiology of the infectious syndrome, facilitating intervention at the community level in the face of outbreaks or epidemics. A variety of molecular techniques have been evaluated for rapid diagnosis of infectious syndromes. These techniques include real-time multiplex PCR, DNA microarray, loop-mediated isothermal amplification, and other similar assays. This review surveys such state-of-the-art technologies.

A simple 96 well microfluidic chip combined with visual and densitometry detection for resource-poor point of care testing

There is a well-recognized need for low cost biodetection technologies for resource-poor settings with minimal medical infrastructure. Lab-on-a-chip (LOC) technology has the ability to perform biological assays in such settings. The aim of this work is to develop a low cost, high-throughput detection system for the analysis of 96 samples simultaneously outside the laboratory setting. To achieve this aim, several biosensing elements were combined: a syringe operated ELISA lab-on-a-chip (ELISA-LOC) which integrates fluid delivery system into a miniature 96-well plate; a simplified non-enzymatic reporter and detection approach using a gold nanoparticle-antibody conjugate as a secondary antibody and silver enhancement of the visual signal; and Carbon nanotubes (CNT) to increase primary antibody immobilization and improve assay sensitivity. Combined, these elements obviate the need for an ELISA washer, electrical power for operation and a sophisticated detector. We demonstrate the use of the device for detection of Staphylococcal enterotoxin B, a major foodborne toxin using three modes of detection, visual detection, CCD camera and document scanner. With visual detection or using a document scanner to measure the signal, the limit of detection (LOD) was 0.5ng/ml. In addition to visual detection, for precise quantitation of signal using densitometry and a CCD camera, the LOD was 0.1ng/ml for the CCD analysis and 0.5 ng/ml for the document scanner. The observed sensitivity is in the same range as laboratory-based ELISA testing. The point of care device can analyze 96 samples simultaneously, permitting high throughput diagnostics in the field and in resource poor areas without ready access to laboratory facilities or electricity.

Novel multiplex real-time PCR system using the SNP technology for the simultaneous diagnosis of Chlamydia trachomatis, Ureaplasma parvum and Ureaplasma urealyticum and genetic typing of serovars of C. trachomatis and U. parvum in NGU

To explore the possibilities of a novel multiplex real-time PCR system for rapid diagnosis, genetic typing of serovars and clinical application in NGU, we developed a multiplex real-time PCR system for the simultaneous diagnosis of Chlamydia trachomatis, Ureaplasma parvum and Ureaplasma urealyticum and molecular detection of serovars of C. trachomatis and U. parvum in NGU using the SNP technology and TaqMan-LNA probe. In 57 pathogen-positive clinical specimens, we identified the following C. trachomatis serovars: D (20.05%, 12/57), E (36.84%, 21/57), F (19.30%, 11/57), G (8.77%, 5/57), H (5.26%, 3/57), J (3.51%, 2/57), and K (5.26%, 3/57). In 115 pathogen-positive clinical specimens, we identified the following U. parvum serovars: 1 (0.87%, 2/115), 3 (55.65%, 64/115), 6 (20.87%, 24/115) and 14 (21.74%, 25/115). Our fast pathogen diagnosis and serotyping assay using real-time TaqMan-LNA PCR may improve our ability to study the pathogenesis and epidemiology of NGU.