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Background Microscopic detection of malaria parasites is labour-intensive, time-consuming, and expertise-demanding. Moreover, the slide interpretation is highly dependent on the staining technique and the technician’s expertise. Therefore, there is a growing interest in next-generation, fully- or semi-integrated microscopes that can improve slide preparation and examination. This study aimed to evaluate the clinical performance of miLab™ (Noul Inc., Republic of Korea), a fully-integrated automated microscopy device for the detection of malaria parasites in symptomatic patients at point-of-care in Sudan. Methods This was a prospective, case–control diagnostic accuracy study conducted in primary health care facilities in rural Khartoum, Sudan in 2020. According to the outcomes of routine on-site microscopy testing, 100 malaria-positive and 90 malaria-negative patients who presented at the health facility and were 5 years of age or older were enrolled consecutively. All consenting patients underwent miLab™ testing and received a negative or suspected result. For the primary analysis, the suspected results were regarded as positive (automated mode). For the secondary analysis, the operator reviewed the suspected results and categorized them as either negative or positive (corrected mode). Nested polymerase chain reaction (PCR) was used as the reference standard, and expert light microscopy as the comparator. Results Out of the 190 patients, malaria diagnosis was confirmed by PCR in 112 and excluded in 78. The sensitivity of miLab™ was 91.1% (95% confidence interval [CI] 84.2–95.6%) and the specificity was 66.7% (95% Cl 55.1–67.7%) in the automated mode. The specificity increased to 96.2% (95% Cl 89.6–99.2%), with operator intervention in the corrected mode. Concordance of miLab with expert microscopy was substantial (kappa 0.65 [95% CI 0.54–0.76]) in the automated mode, but almost perfect (kappa 0.97 [95% CI 0.95–0.99]) in the corrected mode. A mean difference of 0.359 was found in the Bland–Altman analysis of the agreement between expert microscopy and miLab™ for quantifying parasite counts. Conclusion When used in a clinical context, miLab™ demonstrated high sensitivity but low specificity. Expert intervention was shown to be required to improve the device’s specificity in its current version. miLab™ in the corrected mode performed similar to expert microscopy. Before clinical application, more refinement is needed to ensure full workflow automation and eliminate human intervention. Trial registration ClinicalTrials.gov: NCT04558515

Microscopes are indispensable devices of laboratories. They are widely used in industry and science, such as medicine, geology, biology, chemistry and so on. Thanks to the developing technology, manual microscopes are leaving their place to automatic systems. However, automatic microscopy systems are difficult to obtain due to their high costs. The best way to circumvent this problem is to reduce device costs as much as possible. Based on this idea, a fully automated digital microscope system (FADMS) has been proposed as a low-cost prototype. The FADMS can scan and autofocus for various microscopic samples. In addition, it can be controlled over the internet thanks to a developed software and can store scanned microscopic images. The total cost of the developed system is around 2500 US dollars. In experimental studies, mechanical motion sensitivity and focusing tests of the FADMS were performed. Five different methods were tested on peripheral blood smear images for autofocus. According to the results obtained based on six different measurement criteria, Brenner’s and Geusebroek’s method showed the best performance. In positioning tests for the mechanical stage (X and Y axes), the motors in the driving system were moved forward and backward for a distance of 100 μm. The results obtained showed a deviation of 2.6 μm for the X-axis and 3.6 μm for the Y-axis. Experimental results show that micron-sized biological cells can be observed in detail. The FADMS has been designed in a modular structure that allows it to be replaced with lighting, optical system and imaging device alternatives. In terms of performance/cost ratio, the FADMS is attractive for high-throughput microscopy applications ranging from digital pathology to health screening in low-income countries and is considered to be an alternative solution for many industries.

Background: Microscopical screening of cytological samples for the presence of cancer cells at high throughput with sufficient diagnostic accuracy requires highly specialized personnel which is not available in most countries. Methods: Using commercially available automated microscope-based screeners (MotiCyte and EasyScan), software was developed which is able to classify Feulgen-stained nuclei into eight diagnostically relevant types, using supervised machine learning. the nuclei belonging to normal cells were used for internal calibration of the nuclear DNA content while nuclei belonging to those suspicious of being malignant were specifically identified. The percentage of morphologically abnormal nuclei was used to identify samples suspected of malignancy, and the proof of DNA-aneuploidy was used to definitely determine the state malignancy. A blinded study was performed using oral smears from 92 patients with Fanconi anemia, revealing oral leukoplakias or erythroplakias. In an earlier study, we compared diagnostic accuracies on 121 serous effusion specimens. In addition, using a blinded study employing 80 patients with prostate cancer who were under active surveillance, we aimed to identify those whose cancers would not advance within 4 years. Results: Applying a threshold of the presence of >4% of morphologically abnormal nuclei from oral squamous cells and DNA single-cell or stemline aneuploidy to identify samples suspected of malignancy, an overall diagnostic accuracy of 91.3% was found as compared with 75.0% accuracy determined by conventional subjective cytological assessment using the same slides. Accuracy of automated screening effusions was 84.3% as compared to 95.9% of conventional cytology. No prostate cancer patients under active surveillance, revealing DNA-grade 1, showed progress of their disease within 4.1 years. Conclusions: An automated microscope-based screener was developed which is able to identify malignant cells in different types of human specimens with a diagnostic accuracy comparable with subjective cytological assessment. Early prostate cancers which do not progress despite applying any therapy could be identified using this automated approach.

We have developed an automated, highly sensitive and specific method for identifying and enumerating circulating tumour cells (CTCs) in the blood. Blood samples from 10 prostate, 25 colorectal and 4 ovarian cancer patients were analysed. Eleven healthy donors and seven men with elevated serum prostate-specific antigen (PSA) levels but no evidence of malignancy served as controls. Spiking experiments with cancer cell lines were performed to estimate recovery yield. Isolation was performed either by density gradient centrifugation or by filtration, and the CTCs were labelled with monoclonal antibodies against cytokeratins 7/8 and either AUA1 (against EpCam) or anti-PSA. The slides were analysed with the Ikoniscope ® robotic fluorescence microscope imaging system. Spiking experiments showed that less than one epithelial cell per millilitre of blood could be detected, and that fluorescence in situ hybridisation (FISH) could identify chromosomal abnormalities in these cells. No positive cells were detected in the 11 healthy control samples. Circulating tumour cells were detected in 23 out of 25 colorectal, 10 out of 10 prostate and 4 out of 4 ovarian cancer patients. Five samples (three colorectal and two ovarian) were analysed by FISH for chromosomes 7 and 8 combined and all had significantly more than four dots per cell. We have demonstrated an Ikoniscope ® based relatively simple and rapid procedure for the clear-cut identification of CTCs. The method has considerable promise for screening, early detection of recurrence and evaluation of treatment response for a wide variety of carcinomas.

This paper presents the results of the physical and chemical changes of Class F fly ashes exposed to either deionized water or to a 0.4 mol/L KOH solution for 15 or 45 minutes. The changes in physical and chemical makeup of thousands of individual particles before and after being exposed to solutions are analyzed using an autonomous scanning electron microscope. The results show that individual fly ash particles with CaO > 70% by mass completely dissolved. Particles with a CaO < 30% by mass leached sulfur and the remaining undissolved particles showed no measurable change in diameter or physical appearance. Similar observations were made from three different fly ash sources despite showing differences in their total oxide content. These results suggest that only certain particles with a narrow chemistry (CaO < 30% by mass) are responsible for the early age leaching of sulfur. This means that different fly ash particles could be responsible for modifying the sulfur balance in concrete observed in fly ash mixtures at different ages. These observations also give insights into the initial interactions between fly ash and alkali activators in alkali-activated materials. Keywords: automated scanning electron microscope (ASEM); characterization; dissolution; energy-dispersive spectrometer (EDS); fly ash; leaching.

To automate electron microscopy tasks, the main challenge is to integrate image interpretation. This article presents a first achievement in the domain of electron microscopy. ANalysis of IMages for Automatic Targeting and Extraction of Data in Transmission Electron Microscopy (ANIMATED-TEM) is a software toolbox composed of a set of image analysis algorithms and an examination scenario. Combined with microscope software, it runs all the microscope tasks and manages the exploration strategy of the carbon-coated grids on which the sample of interest (viruses, proteins, bi-dimensional crystal of membrane proteins, etc.) has been deposited. ANIMATED-TEM realizes the automatic examination of biological samples, working at several magnifications without human intervention. Online image analysis of micrographs is an essential part both to extract characteristic data and to manage automation, as interesting regions need to be identified to trigger new acquisitions at higher magnifications. This toolbox has been developed to perform high-throughput screening of 2D-crystallization experiments. It is operational on a microscope equipped with an automatic grid loading system, allowing the continuous and automatic analysis of up to 96 samples. Intensive testing over a period of several months confirms that ANIMATED-TEM achieves full automation with an efficient target selection and in a suitable computational time.

The authors describe a method for realigning images from serially sectioned biological specimens that minimizes the effect of artificial deformations in the alignment by applying global elastic constraints. The method is applied to transmission electron microscopy and array tomography image series and is made available through the Fiji platform. Anatomy of large biological specimens is often reconstructed from serially sectioned volumes imaged by high-resolution microscopy. We developed a method to reassemble a continuous volume from such large section series that explicitly minimizes artificial deformation by applying a global elastic constraint. We demonstrate our method on a series of transmission electron microscopy sections covering the entire 558-cell Caenorhabditis elegans embryo and a segment of the Drosophila melanogaster larval ventral nerve cord.

A scanning electron microscope (SEM) provides real-time imaging with nanometer resolution and a large scanning area, which enables the development and integration of robotic nanomanipulation systems inside a vacuum chamber to realize simultaneous imaging and direct interactions with nanoscaled samples. Emerging techniques for nanorobotic manipulation during SEM imaging enable the characterization of nanomaterials and nanostructures and the prototyping/assembly of nanodevices. This paper presents a comprehensive survey of recent advances in nanorobotic manipulation, including the development of nanomanipulation platforms, tools, changeable toolboxes, sensing units, control strategies, electron beam-induced deposition approaches, automation techniques, and nanomanipulation-enabled applications and discoveries. The limitations of the existing technologies and prospects for new technologies are also discussed. Nanorobotics: Thriving under electron microscopes Scanning electron microscopes (SEMs) are powerful platforms for guiding robots to manipulate nanomaterials and prototype nanodevices. Yu Sun from the University of Toronto, Canada, and his colleagues surveyed recent progress in the field, reporting that the real-time, nanometer-scale imaging capabilities of SEMs and nanomanipulators with sub-nanometer motion resolutions have led to breakthroughs in applications such as automated DNA extraction, 3D manipulation of nanomaterials and the electrical characterization of transistors. Tools such as nano probe and micromachined ‘grippers’ embedded with force-feedback sensors are used to stretch, slice and shovel nanoscale objects, whereas electron-beam techniques can be used to weld such materials together. Implementing control and sensing and actuation schemes compatible with SEM’s vacuum environment remains challenging, however. Although virtual-reality techniques have enhanced human-robot interactions, autonomous nanomanipulation is still advancing to offer better consistency and speeds in the nano world.

Background Calcium imaging enables real-time recording of cellular activity across various biological contexts. To assess the activity of individual cells, researchers must segment images into the individual cells. While intensity-based threshold algorithms allow for automatic image segmentation in sparsely packed tissues, they perform poorly in densely packed organs such as cardiomyocytes or the pancreatic islet. To study these tissues, investigators typically manually outline the cells based on visual inspection. This manual cell masking introduces potential user error. To address this error, we developed the Correlation-Refined Image Segmentation Process (CRISP). CRISP utilizes interpixel correlations to refine user drawn cell masks (cell mask refinement) or automatically masks cells by identifying the largest circle that captures only pixels within the cell (semi-minor axis identification). Results CRISP cell mask refinement had an area under the receiver operating curve of 0.835, indicating good model performance on the training data set. CRISP had 77% accuracy when testing on a separate data set, which came from a different mouse model imaged with a different microscope than the training data set. CRISP cell mask refinement significantly improved the accuracy of functional network analysis compared to non-CRISP refined cell masks. CRISP automated semi-minor axis identification had an area under the receiver operating curve under the curve of 0.989, indicating strong model performance. Conclusions Inaccurate cell masking can result in inaccurate scientific interpretations of calcium images. Utilizing interpixel correlations, we developed two transparent algorithms that can be used for image segmentation in densely packed tissues. These algorithms may allow for more accurate and reproducible cell masking.

The freely available WormToolbox enables high-throughput image analysis of a variety of phenotypes of Caenorhabditis elegans in liquid culture and should prove useful for image-based screens. We present a toolbox for high-throughput screening of image-based Caenorhabditis elegans phenotypes. The image analysis algorithms measure morphological phenotypes in individual worms and are effective for a variety of assays and imaging systems. This WormToolbox is available through the open-source CellProfiler project and enables objective scoring of whole-worm high-throughput image-based assays of C. elegans for the study of diverse biological pathways that are relevant to human disease.