Conventional Glass Slides Research Articles

Transforming Diagnostics: A Comprehensive Review of Advances in Digital Pathology.

Digital pathology has emerged as a revolutionary field, transforming traditional diagnostic practices by integrating advanced imaging technologies, computational tools, and artificial intelligence (AI). Adopting digital slides over conventional glass slides enables high-resolution imaging, facilitating remote consultations, second opinions, and telepathology. The digitalization of pathology laboratories enhances workflow efficiency and allows for large-scale data storage, retrieval, and analysis, paving the way for developing robust diagnostic algorithms. One of the most transformative aspects of digital pathology is its synergy with AI and machine learning (ML). These technologies have enabled the automation of repetitive processes, including diseased feature detection, biomarker quantification, and tissue segmentation. This has decreased inter-observer variability and increased diagnostic accuracy. AI-driven algorithms are particularly beneficial in complex cases, assisting pathologists in detecting subtle patterns that might be missed through manual examination. Furthermore, digital pathology plays a critical role in personalized medicine by enabling the precise characterization of tumors, which leads to targeted therapy decisions. Integrating digital pathology with genomics and other omics data holds promise for a more holistic understanding of diseases, driving innovation in diagnostics and treatment. However, the transition to digital pathology is challenging. Issues such as data standardization, regulatory compliance, and the need for robust IT infrastructure must be addressed to realize its full potential. This review provides a detailed examination of these advances, their clinical applications, and the challenges faced in the widespread adoption of digital pathology. As the field continues to evolve, it is poised to play a pivotal role in shaping the future of diagnostics, offering new possibilities for improving patient outcomes. This comprehensive review explores the significant advances in digital pathology, highlighting its impact on diagnostics, research, and patient care.

Standardized Clinical Annotation of Digital Histopathology Slides at the Point of Diagnosis

As digital pathology replaces conventional glass slide microscopy as a means of reporting cellular pathology samples, the annotation of digital pathology whole slide images is rapidly becoming part of a pathologist’s regular practice. Currently, there is no recognizable organization of these annotations, and as a result, pathologists adopt an arbitrary approach to defining regions of interest, leading to irregularity and inconsistency and limiting the downstream efficient use of this valuable effort. In this study, we propose a Standardized Annotation Reporting Style for digital whole slide images. We formed a list of 167 commonly annotated entities (under 12 specialty subcategories) based on review of Royal College of Pathologists and College of American Pathologists documents, feedback from reporting pathologists in our NHS department, and experience in developing annotation dictionaries for PathLAKE research projects. Each entity was assigned a suitable annotation shape, SNOMED CT (SNOMED International) code, and unique color. Additionally, as an example of how the approach could be expanded to specific tumor types, all lung tumors in the fifth World Health Organization of thoracic tumors 2021 were included. The proposed standardization of annotations increases their utility, making them identifiable at low power and searchable across and between cases. This would aid pathologists reporting and reviewing cases and enable annotations to be used for research. This structured approach could serve as the basis for an industry standard and be easily adopted to ensure maximum functionality and efficiency in the use of annotations made during routine clinical examination of digital slides.

Digital cytology: Current status and future prospects.

In this paper, we reviewed the basic principle and the currentstatus of digital cytopathology. We reviewed the published papers on digitalcytology and analysed its future prospects. Virtualcytology using digital platform is being increasingly used to render diagnosisrather than conventional glass slide microscopy. Whole slide imaging (WSI)offers the prospect of true virtual microscopy and in the near future, may evenreplace glass slides in routine practice. It may be pivotal in diagnosing andtraining pathology graduates faster and more accurately. The digital cytopathology is a promising field and may have great impact indiagnosis, research and teaching.

Diagnostic validation of a portable whole slide imaging scanner for lymphoma diagnosis in resource-constrained setting: A cross-sectional study

BackgroundTelepathology utilizing high-throughput static whole slide image scanners is proposed to address the challenge of limited pathology services in resource-restricted settings. However, the prohibitive equipment costs and sophisticated technologies coupled with large amounts of space to set up the devices make it impractical for use in resource-limited settings. Herein, we aimed to address this challenge by validating a portable whole slide imaging (WSI) device against glass slide microscopy (GSM) using lymph node biopsies from suspected lymphoma cases from Sub-Saharan Africa. Material and methodsThis was part of a multicenter prospective case–control head-to-head comparison study of liquid biopsy against conventional pathology. For the portable WSI scanner validation, the study pathologists evaluated 105 surgical lymph node specimens initially confirmed by gold-standard pathology between February and December 2021. The tissues were processed according to standard protocols for Hematoxylin and Eosin (H&E) and Immunohistochemistry (IHC) staining by well-trained histotechnicians, then digitalized the H& E and IHC slides at each center. The digital images were anonymized and uploaded to a HIPAA-compliant server by the histotechnicians. Three study pathologists independently accessed and reviewed the images after a 6-week washout. The agreement between diagnoses established on GSM and WSI across the pathologists was described and measured using Cohens’ kappa coefficient (κ). ResultsOn GSM, 65.5% (n=84) of specimens were lymphoma; 25% were classified as benign, while 9.5% were metastatic. Morphological quality assessment on GSM and WSI established that 79.8% and 53.6% of cases were of high quality, respectively. When diagnoses by GSM were compared to WSI, the overall concordance for various diagnostic categories was 93%, 100%, and 86% for lymphoma, metastases, and benign conditions respectively. The sensitivity and specificity of WSI for the detection of lymphoma were 95.2% and 85.7%, respectively, with an overall inter-observer agreement (κ) of 0.86; 95% CI (0.70–0.95). ConclusionsWe demonstrate that mobile whole slide imaging (WSI) is non-inferior to conventional glass slide microscopy (GSM) for the primary diagnosis of malignant infiltration of lymph node specimens. Our results further provide proof of concept that mobile WSI can be adapted to resource-restricted settings for primary surgical pathology and would significantly improve patient outcomes.

Prior to Implementation of Digital Pathology-Assessment of Expectations among Staff by Means of Normalization Process Theory.

The Region of Southern Denmark is the first in Denmark to implement digital pathology (DIPA), starting at the end of 2020. The DIPA process involves changes in workflow, and the pathologist will have to diagnose based on digital whole slide imaging instead of through the traditional use of the conventional light microscope and glass slides. In addition, in the laboratory, the employees will have to implement one more step to their workflow—scanning of tissue. The aim of our study was to assess the expectations and readiness among employees and management towards the implementation of DIPA, including their thoughts and motivations for starting to use DIPA. We used a mixed-method approach. Based on the findings derived from 18 semi-structured interviews with employees from the region’s departments of pathology, we designed a questionnaire, including questions from the normalization measure development tool. The questionnaires were e-mailed to 181 employees. Of these employees, 131 responded to the survey. Overall, they reported feeling sufficiently tech-savvy to be able to use DIPA, and they had high expectations as well as motivation and readiness for the upcoming changes. However, the employees were skeptical regarding the allocation of resources, and few were aware of reports about the effects of DIPA. Based on the findings, it seems to be important to provide not only a thorough introduction to the new intervention and the changes it will entail, but also to continue to ensure that the staff know how it works and why it is necessary to implement.

The role of telepathology in diagnosis of pre-malignant and malignant cervical lesions: Implementation at a tertiary hospital in Northern Tanzania.

IntroductionAdequate and timely access to pathology services is a key to scale up cancer control, however, there is an extremely shortage of pathologists in Tanzania. Telepathology (scanned images microscopy) has the potential to increase access to pathology services and it is increasingly being employed for primary diagnosis and consultation services. However, the experience with the use of telepathology in Tanzania is limited. We aimed to investigate the feasibility of using scanned images for primary diagnosis of pre-malignant and malignant cervical lesions by assessing its equivalency to conventional (glass slide) microscopy in Tanzania.MethodsIn this laboratory-based study, assessment of hematoxylin and eosin stained glass slides of 175 cervical biopsies were initially performed conventionally by three pathologists independently. The slides were scanned at x 40 and one to three months later, the scanned images were reviewed by the pathologists in blinded fashion. The agreement between initial and review diagnoses across participating pathologists was described and measured using Cohen’s kappa coefficient (κ).ResultsThe overall concordance of diagnoses established on conventional microscopy compared to scanned images across three pathologists was 87.7%; κ = 0.54; CI (0.49–0.57).The overall agreement of diagnoses established by local pathologist on conventional microscopy compared to scanned images was 87.4%; κ = 0.73; CI (0.65–0.79). The concordance of diagnoses established by senior pathologist compared to local pathologist on conventional microscopy and scanned images was 96% and 97.7% respectively. The inter-observer agreement (κ) value were 0.93, CI (0.87–1.00) and 0.94, CI (0.88–1.00) for conventional microscopy and scanned images respectively.ConclusionsAll κ coefficients expressed good intra- and inter-observer agreement, suggesting that telepathology is sufficiently accurate for primary diagnosis in surgical pathology. The discrepancies in interpretation of pre-malignant lesions highlights the importance of p16 immunohistochemistry in definitive diagnosis in these lesions. Sustainability factors including hardware and internet connectivity are essential components to be considered before telepathology may be deemed suitable for widely use in Tanzania.

Virtual Microscopy

Objectives: The objectives of this study were as follows: (1) to provide an overview of the feasibility, utility, merits, and demerits of virtual microscopy (VM) in pathological diagnostics and (2) to evaluate its advantages in dental and medical teaching over conventional microscopes. Materials and Methods: A literature survey was carried out in August 2020 in electronic databases such as PubMed using keywords such as virtual microscopy and whole slide imaging. The searches revealed 956 articles out of which 36 were selected after reading the full-text articles. Results: The review of 36 articles revealed that VM or whole-slide imaging (WSI) allows access to entire scanned sections of tissue that can be viewed on a computer in exactly the same way as conventional glass slides with a microscope and can be explored at several magnifications. VM offers many advantages like ease of accessibility through the Internet anytime or in any place, and moreover, the virtual slide does not get damaged or fade away like glass slide. Since it increases learning and comprehension, virtual microscopes have been used extensively in dental and medical education. Conclusions: VM opens a new world in tissue-based diagnosis through digitization of slides. The experiences of telepathology applications have already proved that it is a promising technology which has been adopted by histopathologists and cytologists across the world and contributing immensely to telepathology consultation in underserved areas. It is a feasible, valid, and approved technology for pathological diagnosis.

Evaluation of penetration speed of liquids into skin using a terahertz time-of-flight method

Analyzing the penetration of cosmetic/medical lotions and creams into the skin is important for evaluating their effectiveness. Hence, the penetration speed of liquids into chicken and pig skins was evaluated using a terahertz (THz) time-of-flight method. An arsenide-free disposable THz emitter comprising a silicon film on a sapphire substrate was developed for practical measurements using skin samples. The skin sample was mounted on the THz emitter surface directly so that the generated THz pulses in the silicon film were easily focused on the skin sample. To evaluate the time evolution of the penetration depth, the arrival times of the reflected THz pulses at the edge of the liquid-penetrated region on the skin were observed. As a preliminary experiment, measurements using a stack of conventional glass slides were conducted. In addition, the penetration speed into the chicken and pig skin was compared to prove the practical applicability of our method.

Teleophthalmology Using Whole Slide Imaging (WSI): Clinical-Pathological Correlation Even Without Own Histological Laboratory

Telepathology has experienced enormous growth over the last two decades due to significant advances in IT and has led to the introduction of innovative solutions for digital imaging in ophthalmology. Whole Slide Imaging (WSI), where conventional glass slides are fully scanned, offers a wide range of applications, including remote (conciliary) diagnostics, second opinions, (remote) teaching and research and presentation. In addition to qualified and experienced personnel, a comparatively expensive basic equipment has so far also been an essential requirement. The focus ophthalmology at the Eye Centre in Freiburg is able to involve a de facto unlimited number of users and consulting partners (also overseas) in the digital microscopy of identical sections independent of location, device and time. This is done simply by using the internet. This procedure has proven to be very successful and opens up completely new avenues, not only for correct diagnosis (clinical-pathological correlation), but also for education and training. Preparation and distribution of further histological slides in addition to the scanned slide is not required for small specimens with scant material, for example, nor is it necessary to purchase microscopes for the participants if funds are lacking or the infrastructure is unsuitable. When dealing with transferring data, it is essential to comply with data protection regulations.

Structured illumination microscopy using a photonic chip

Structured illumination microscopy (SIM) enables live cell, super-resolution imaging at high speeds. SIM uses sophisticated optical systems to generate pre-determined excitation light patterns, and reconstruction algorithms to enhance the resolution by up to a factor of two. The optical set-up of SIM relies on delicate free-space optics to generate the light patterns, and a high numerical aperture objective lens to project the pattern on the sample. These arrangements are prone to miss-alignment, often with high costs, and with the final resolution-enhancement being limited by the numerical aperture of the collection optics. Here, we present a photonic-chip based total internal reflection fluorescence (TIRF)-SIM that greatly reduces the complexity of the optical setup needed to acquire TIRF-SIM images. This is achieved by taking out the light delivery from the microscope and transferring it to a photonic-chip. The conventional glass slide is replaced by the planar photonic chip, that both holds and illuminates the specimen. The chip is used to create a standing wave interference pattern, which illuminates the sample via evanescent fields. The phase of the interference pattern is controlled by the use of thermo-optical modulation, leaving the footprint of the light illumination path for the SIM system to around 4 by 4 cm$^2$. Furthermore, we show that by the use of the photonic-chip technology, the resolution enhancement of SIM can be increased above that of the conventional approach. In addition, by the separation of excitation and collection light paths the technology opens the possibility to use low numerical objective lenses, without sacrificing on the SIM resolution. Chip-based SIM represents a simple, stable and affordable approach, which could enable widespread penetration of the technique and might also open avenues for high throughput optical super-resolution microscopy.

Automated Sectioning, Staining, and Imaging of Histologically Preserved Tissues

ObjectiveTissue microstructure contains a wealth of information with extraordinary value for basic research and therapy discovery. But because histology is manual and tedious, tissue protocols are not set up for highly automated, structured, data‐driven methods that prevail in other areas of life sciences research.MethodsWe adapt block‐face lamination array tomography (B‐FLAT) for automated, high‐throughput histological sectioning. We can section, stain, mount, image, and microdissect paraffin‐embedded tissue sections on tape, allowing for much higher speed, accuracy, and consistency in section capture, as well as automated imaging and image registration.ResultsWe successfully captured, deparaffinized, stained, and imaged serial histological sections on tape. Separately, we validated numerous histological and immunohistochemical (IHC) stains relevant to renal pathology and established their equivalence to conventional glass slide methods. We generated a series of at least 30 hematoxylin and eosin (H&E)‐stained mouse kidney sections, digitally imaged and registered at 20X magnification, and reconstructed entire renal glomeruli with nuclear resolution adequate for algorithmic cell counting.ConclusionsOur automation approach recapitulates the performance of conventional histology practices, but allows for much higher speed, accuracy, and consistency in section capture. This enables future development to dramatically improve section quality, throughput, and sample biases.Support or Funding InformationFunding provided by NIH grant 1R43DK120281‐01

“Teledermatopathology: A Review”

In this review, we will cover definitions of relevant terms, present need, technologic requirements, regulation, validation, and current and emerging applications of teledermatopathology. Numerous studies have found no significant diagnostic discordance between teledermatopathology and glass microscopy in evaluation of melanocytic, non-melanocytic, and inflammatory diagnoses. Teledermatopathology has led to a significant difference in patient management in low-resource settings. Furthermore, studies using static images acquired using smartphones and microscope adapters have high diagnostic concordance with conventional glass slide review. Teledermatopathology is a new method to address healthcare disparity in access to dermatopathology services on a local and international level, reduce costs, and further physician education. Adoption of teledermatopathology remains limited by regulatory and remuneration barriers and high cost and storage requirements of initiation.

The Next Generation Robotic Microscopy for Intraoperative Teleneuropathology Consultation

Introduction: Teleneuropathology at our institution evolved over the last 17 years from using static to dynamic robotic microscopy. Historically (2003-2007), using older technology, the deferral rate was 19.7%, and the concordance was 81% with the final diagnosis. Two years ago, we switched to use hybrid robotic devices to perform these intraoperative (IO) consultations because our older devices were obsolete. The aim of this study was to evaluate the impact this change had on our deferral and concordance rates with teleneuropathology using this newer instrument. Materials and Methods: Aperio LV1 4-slide capacity hybrid robotic scanners with an attached desktop console (Leica Biosystems, Vista, CA, USA) and GoToAssist (v4.5.0.1620, Boston, MA, USA) were used for IO telepathology cases. A cross-sectional comparative study was conducted comparing teleneuropathology from three remote hospitals (193 cases) to IO neuropathology consultation performed by conventional glass slide examination at a light microscope (310 cases) from the host hospital. Deferral and concordance rates were compared to final histopathological diagnoses. Results: The deferral rate for IO teleneuropathology was 26% and conventional glass slide 24.24% (P = 0.58). The concordance rate for teleneuropathology was 93.94%, which was slightly higher than 89.09% for conventional glass slides (P = 0.047). Conclusion: The new hybrid robotic device for performing IO teleneuropathology interpretations at our institution was as effective as conventional glass slide interpretation. While we did observe a noticeable change in the deferral rate compared to prior years, we did appreciate the marked improvement of the concordance rate using this new hybrid scanner.

Highly Transparent Cyclic Olefin Copolymer Film with a Nanotextured Surface Prepared by One-Step Photografting for High-Density DNA Immobilization.

Compared with conventional glass slides and two-dimensional (2D) planar microarrays, polymer-based support materials and three-dimensional (3D) surface structures have attracted increasing attention in the field of biochips because of their good processability in microfabrication and low cost in mass production, as well as their improved sensitivity and specificity for the detection of biomolecules. In the present study, UV-induced emulsion graft polymerization was carried out on a cyclic olefin copolymer (COC) surface to generate 3D nanotextures composed of loosely stacked nanoparticles with a diameter of approximately 50 nm. The introduction of a hierarchical nanostructure on a COC surface only resulted in a 5% decrease in its transparency at a wavelength of 550 nm but significantly increased the surface area, which markedly improved immobilization density and efficiency of an oligonucleotide probe compared with the functional group and polymer brush-modified substrates. The highest immobilization efficiency of the probes reached 93%, and a limit of detection of 75 pM could be obtained. The hybridization experiment demonstrated that the 3D gene chip exhibited excellent sensitivity for target DNA detection and single-nucleotide polymorphism discrimination. This one-step approach to the construction of nanotextured surfaces on the COC has promising applications in the fields of biochips and immunoassays.

Improving Classification of Breast Cancer by Utilizing the Image Pyramids of Whole-Slide Imaging and Multi-Scale Convolutional Neural Networks.

Whole-slide imaging (WSI) is the digitization of conventional glass slides. Automatic computer-aided diagnosis (CAD) based on WSI enables digital pathology and the integration of pathology with other data like genomic biomarkers. Numerous computational algorithms have been developed for WSI, with most of them taking the image patches cropped from the highest resolution as the input. However, these models exploit only the local information within each patch and lost the connections between the neighboring patches, which may contain important context information. In this paper, we propose a novel multi-scale convolutional network (ConvNet) to utilize the built-in image pyramids of WSI. For the concentric image patches cropped at the same location of different resolution levels, we hypothesize the extra input images from lower magnifications will provide context information to enhance the prediction of patch images. We build corresponding ConvNets for feature representation and then combine the extracted features by 1) late fusion: concatenation or averaging the feature vectors before performing classification, 2) early fusion: merge the ConvNet feature maps. We have applied the multi-scale networks to a benchmark breast cancer WSI dataset. Extensive experiments have demonstrated that our multiscale networks utilizing the WSI image pyramids can achieve higher accuracy for the classification of breast cancer. The late fusion method by taking the average of feature vectors reaches the highest accuracy (81.50%), which is promising for the application of multi-scale analysis of WSI.

A U-net based approach to epidermal tissue segmentation in whole slide histopathological images

Malignant melanoma is a severe and aggressive type of skin cancer, with a rapid decrease in survival rate if not diagnosed and treated at an early stage. Histopathological examination of hematoxylin and eosin stained tissue biopsies under a light microscope is currently the gold standard for diagnosis. However, this manual examination is a difficult and time-consuming task, and diagnosis is often subject to intra- and inter-observer variability. With more pathology departments starting to convert conventional glass slides into digital resources, a Computer Aided Diagnostic (CAD) system that can automate part of the diagnostic process will help address these challenges. It is expected to reduce examination time, increase diagnostic accuracy, and reduce diagnostic variations. An important initial step in developing such a system is an automated epidermis segmentation algorithm, since several important diagnostic factors are within or seen relatively to the epidermis’ location. In this paper, we propose a new epidermis segmentation technique built on Convolutional Neural Networks. We trained an U-net based architecture end-to-end, with sim 380hbox {k} overlapping high resolution image patches at 512 times 512 pixels, extracted and augmented from 36 digitized histopathological images from two different clinical sites, to discriminate pixels as either epidermal or non-epidermal. The proposed technique was evaluated on 33 test images, where we achieved a mean Positive Predictive Value at 0.89pm 0.16, Sensitivity at 0.92pm 0.1, Dice Similarity Coefficient at 0.89pm 0.13 and a Matthews Correlation Coefficient at 0.89pm 0.11, showing a superior performance when compared to existing techniques. Our algorithm also proves to be robust to variations in staining, tissue thickness and laboratory pre-processing.

Efficient Screening of Combinatorial Peptide Libraries by Spatially Ordered Beads Immobilized on Conventional Glass Slides.

Screening of one-bead-one-compound (OBOC) libraries is a proven procedure for the identification of protein-binding ligands. The demand for binders with high affinity and specificity towards various targets has surged in the biomedical and pharmaceutical field in recent years. The traditional peptide screening involves tedious steps such as affinity selection, bead picking, sequencing, and characterization. Herein, we present a high-throughput “all-on-one chip” system to avoid slow and technically complex bead picking steps. On a traditional glass slide provided with an electrically conductive tape, beads of a combinatorial peptide library are aligned and immobilized by application of a precision sieve. Subsequently, the chip is incubated with a fluorophore-labeled target protein. In a fluorescence scan followed by matrix-assisted laser desorption/ionization (MALDI)-time of flight (TOF) mass spectrometry, high-affinity binders are directly and unambiguously sequenced with high accuracy without picking of the positive beads. The use of an optimized ladder sequencing approach improved the accuracy of the de-novo sequencing step to nearly 100%. The new technique was validated by employing a FLAG-based model system, identifying new peptide binders for the monoclonal M2 anti-FLAG antibody, and was finally utilized to search for IgG-binding peptides. In the present format, more than 30,000 beads can be screened on one slide.

The California Telepathology Service: UCLA's Experience in Deploying a Regional Digital Pathology Subspecialty Consultation Network

Background: The need for extending pathology diagnostic expertise to more areas is now being met by the maturation of technology that can effectively deliver this level of care. The experience and lessons learned from our successfully deployed International Telepathology Service (ITS) to a hospital system in China guided us in starting a domestic telepathology network, the California Telepathology Service (CTS). Many of the lessons learned from the ITS project informed our decision-making for the CTS. New challenges were recognized and overcome, such as addressing the complexity and cost-benefit tradeoffs involved in setting up a digital consultation system that competes with an established conventional glass slide delivery system. Methods: The CTS is based on a hub-and-spoke telepathology network using Leica Biosystems whole-slide image scanners and the eSlide Manager (eSM Version 12.3.3.7055, Leica Biosystems) digital image management software solution. The service currently comprises six spoke sites (UC San Diego [UCSD], UC Irvine [UCI], UC Davis, Northridge Hospital Medical Center [NHMC], Olive View Medical Center [OVMC], and Children's Hospital Los Angeles) and one central hub site (UCLA Medical Center). So far, five sites have been validated for telepathology case consultations following established practice guidelines, and four sites (UCI, UCSD, NHMC, and OVMC) have activated the service. Results: For the active spoke sites, we reviewed the volume, turnaround time (TAT), and case types and evaluated for utility and value. From May 2017 to July 2018, a total of 165 cases were submitted. Of note, digital consultations were particularly advantageous for preliminary kidney biopsy diagnoses (avg TAT 0.7 day). Conclusion: For spoke sites, telepathology provided shortened TAT and significant financial savings over hiring faculty with expertise to support a potentially low-volume service. For the hub site, the value includes exposure to educationally valuable cases, additional caseload volume to support specialized services, and improved communication with referring facilities over traditional carrier mail. The creation of a hub-and-spoke telepathology network is an expensive undertaking, and careful consideration needs to be given to support the needs of the clinical services, acquisition and effective deployment of the appropriate equipment, network requirements, and laboratory workflows to ensure a successful and cost-effective system.

Highly sensitive metal-enhanced fluorescence biosensor prepared on electrospun fibers decorated with silica-coated silver nanoparticles

A new metal-enhanced fluorescence (MEF)-based biosensor platform was prepared on fibrous substrates. First, polycaprolactone (PCL) fibers were obtained via electrospinning process. PCL fibers were decorated with photoreduced silver nanoparticles followed by silica coating, generating silver-decorated PCL fibers with a silica layer (Ag@SiO2-PCL). The silica layer acted as a spacer between the silver nanoparticles and the fluorescent molecules to optimize the MEF effect. The MEF was obtained from the silver-decorated PCL fibers, the extent of which could be controlled by the thickness of the silica layer. The fibrous structure of Ag@SiO2-PCL had higher protein loading capacity than conventional two-dimensional glass slides due to its large surface area, while the presence of silica-coated silver nanoparticles resulted in higher fluorescence intensity than silica-coated PCL fibers (SiO2-PCL) without silver nanoparticles via the MEF effect. Both features of Ag@SiO2-PCL were combined to produce combined effects in improving the performance of fluorescence-based biosensing. According to immunobinding assays between fluorescently labeled anti-IgG and IgG immobilized onto different substrates, Ag@SiO2-PCL had much better sensing performance in terms of sensitivity and detection limit than glass slides and SiO2-PCL due to the combined effects of a large surface area and the MEF effect.

Clinical comparison of liquid-based and conventional cytology of oral brush biopsies: a randomized controlled trial

BackgroundExfoliative cytology performed on oral brush samples can help dentists to decide, whether a given oral lesion is (pre-) malignant. The use of non-invasive brush biopsies as an auxiliary tool in the diagnosis of oral mucosal lesions has gained renewed interest since improvements in cytological techniques such as the development of adjuvant diagnostic tools and liquid-based cell preparation techniques.MethodsThe aim of this study was to compare the quality of two different preparation techniques (cell collectors): the conventional transfer procedure to glass slides and the so-called liquid-based cytology preparation method. Cell smears were collected from 10 orally healthy individuals (mean age: 24 years) from the palatine mucosa at two different times (baseline and 4 weeks later). Slides of both techniques were stained by Giemsa (n = 40) and May-Gruenwald Giemsa (n = 40). The statistical analysis was performed with Excel.ResultsOn specimen analysis, the liquid-based cytology showed statistically significant improvement compared to conventional glass sides (p < 0.001). Thin layers, which were performed by liquid-based cytology showed significantly better results in the parameters (p < 0.001): uniform distribution, cellular overlapping, cellular disformation, mucus, microbial colonies and debris. The conventional glass slides approach showed more cell overlapping and contamination with extraneous material than thin layers, which were performed by Orcellex® Brush cell collectors.ConclusionsBoth techniques are diagnostically reliable. The liquid-based method showed an overall improvement on sample preservation, specimen adequacy, visualization of cell morphology and reproducibility.Liquid-based cytology simplifies cell collection due to easier handling and less transfer errors by dentists.