Development of a rapid diagnostic test for the detection of antibodies or antigens to Coronavirus (COVID-19)

Theglobal health crisis caused by COVID-19 has overwhelmed both healthcaresettings and economies globally. Whilst mass population testing has improveddrastically, recent reviews of existing methods have highlighted variousshortcomings with these methods. Theaim of this project was to investigate whether the LAA could be modified andutilised as rapid detection test which either matched or exceeded the existingsensitivity and specificity values.   TheLAA investigated whether the COVID-19 spike protein could be detected insamples. COVID-19 specific IgM and IgG were used in conjunction with a seriesof non-specific antigens. Control or AG containing samples weremixed with AB-microsphere complexes on glass microscope slides. Manualvisualisation identified various levels of agglutination. Light microscopy andspectrophotometry at 405nm determined that the LAA could detect at least 2.3ngof spike protein.  Theparticle counting tool of ImageJ was utilised to obtain a dataset which wassubjected to statistical analysis which indicated that there was a significantdifference between control samples and live tests, P = 0.000102 for the spikeprotein assay and P = 0.254 for the non-specific assay respectively. Theresults obtained fell in line with a similar study conducted by Buffin et al in2018. Theanalytical methods used in this project twinned with data obtained in previousstudies supports the significant difference between control values and livetest values. The LAA is easier, quicker to use (results in ≤ 30 minutes) andcheaper, with potentially better sensitivity to existing methods. This couldbenefit high and low-income countries alike upon further research andoptimisation. 

PSXII-14 Estimation of phosphatidylserine positive sperm in fresh bull semen

Previous research demonstrated that phosphatidylserine (PS), a marker for apoptosis, plays a role in murine sperm fertilization capacity; however, less is known of the role of PS in bovine fertilization. The objective of this experiment was to determine the concentration of PS positive sperm on fresh bovine semen (n = 4). A breeding soundness evaluation was performed and electroejaculation was used to collect semen which was immediately evaluated for ejaculate density and gross motility through visual evaluation. Semen smears of semen mixed with an eosin-nigrosin strain were prepared on glass microscope slides. Semen was mixed with OptiXcell™ (IMV Technologies) semen extender, a 0.5 mL sample from each bull was washed with non-capacitating media and then incubated at 37.5°C 5% CO2 with capacitating media for 60 minutes. Samples were stained with Annexin V FITC and 7AAD for 15 minutes each. Samples were analyzed using a Flow Cytometer to determine the percentage of PS positive sperm. Bull 1 had a scrotal circumference of 37.5 cm, ejaculate density of 400–750 million sperm/mL, very good gross motility, 78% sperm with normal morphology, and 14.65% PS positive sperm. Bull 2 had a scrotal circumference of 37 cm, ejaculate density of 400–750 million sperm/mL, very good gross motility, 84% sperm with normal morphology, and 17.05% PS positive sperm. Bull 3 had a scrotal circumference of 39.5 cm, ejaculate density of 250–400 million sperm/mL, fair gross motility, 48% sperm with normal morphology, and 12.8% PS positive sperm. Bull 4 had a scrotal circumference of 38 cm, ejaculate density of 400–750 million sperm/mL, good gross motility, 68% of sperm with normal morphology, and 12.65% PS positive sperm. Our data demonstrate the possibility of identifying live PS positive sperm in fresh ejaculate from bulls. The possibility exists that PS plays a role in sperm oocyte fusion and fertilization in the bovine.

Biruta Rasiņa’s collection of scale insects (Hemiptera: Sternorrhyncha: Coccomorpha) at the Latvian National Museum of Natural History, including type material of several species

Information about the scale insect (Hemiptera: Coccomorpha) fauna of Latvia was first published in the second half of the 18th century, but the most serious and purposeful research on it was carried out between the 1920s and the early 1970s. Biruta Rasiņa, in collaboration with her colleagues, conducted the most extensive research on the scale insect fauna in Latvia in the 20th century. She was active in science from the 1940s until the early 1970s, and described eight new species between 1966 and 1971. According to modern taxonomy, seven names of the taxa she described are now synonyms of the names of other species, but one of her species names is still considered to be valid. Previously it was believed that the type material of the taxa she described, and all the other scale insect material she collected, had been lost. For an indefinite period of time the Latvian National Museum of Natural History had stored a collection of unaudited and still unregistered material, thought to be a collection of plant damages collected by Alfrēds Rasiņš. However, inspection of the material showed that it was in fact Biruta Rasiņa’s collection of scale insects, which contained both dry and ethanol-preserved material as well as microscope slides. The material has now been audited and registered in the museum’s collection. Most of the material was collected in Latvia, but the material also includes samples from other countries (Armenia, Belarus, Estonia, Georgia, Kazakhstan, Lithuania, Poland, Russian Federation and Ukraine). The collection includes samples of 75 species from eight families, of which 50 species were collected in the wild, 20 in greenhouses and indoors, and 5 species were found on imported fruits. Biruta Rasiņa’s collection of scale insects is the only known important collection of scale insects in Latvia, and is of national significance. A catalogue of the collection is therefore provided in this paper.

‘A method for safe transmission’: the microscope slides of the American Postal Microscopical Club

In the 1870s, microscopy societies began to proliferate in the United States. Most of these societies attracted microscopists from surrounding cities, but the American Postal Microscopical Club, modelled on the British Postal Microscopical Society, used the postal system to connect microscopists scattered across the country. Club members exchanged microscope slides and notes following a chain-letter system. The main objective of the club was to teach its members how to make permanent slides. Preparation and mounting methods required technical skill, which was, as even club members had to admit, difficult to learn without personal instruction. Yet members developed ways to share craft knowledge through the post. Drawing on the private notes of a member and published reports on the slides circulated, this paper challenges the widespread assumption that the generation of craft knowledge depended on the co-location of artisans. It argues that microscopists’ knowledge of preparation methods was intertwined with their skill in building and navigating information infrastructures, and that by tracing these infrastructures we gain a better understanding of how craft knowledge travelled in the late nineteenth century.

Effects of Automation on Sustainability of Immunohistochemistry Laboratory

The COVID-19 pandemic that hit the world recently caused numerous changes affecting the health system in every department. Reduced staff numbers, mostly due to illness, led to an increase in automation at every stage of laboratory work. The immunohistochemistry (IHC) laboratory conducts a high volume of slide staining every day. Therefore, we analyzed time and total costs required to obtain IHC slides in both the manual and automated way, comparing their efficiency by processing the same sample volume (48 microscope slides—the maximum capacity that an automated immunostainer—DAKO, Autostainer Link 48, Part No AS48030—can process over a single cycle). The total IHC procedure time to run 48 slides manually by one technician was 460 min, while the automated process finished a cycle within 390 min (15.22% less time). The final cost of a single manual IHC slide was 12.26 EUR and 7.69 EUR for slides labeled in the automated immunostainer, which reduced final costs by 37.27%. Thus, automation of the IHC procedure reduces the time and costs of the IHC process, contributing significantly to the sustainability of the healthcare system during the COVID-19 pandemic, overcoming insufficient human resources.

Impact of vertical succussion strokes vs. vortex potentization on droplet evaporation patterns obtained from Iscador Quercus 3x potency

Background Pharmaceutical processing of homeopathic potencies consists of consecutively performed dilution and succussion steps. While the dilution steps are well defined, the manner of performing the succussions varies broadly among potency producers. Aims To study the impact of potentization consisting in the performance of vertical succussion strokes vs. vortex-like flow on droplet evaporation patterns obtained from Iscador Quercus 3x (ISCQ 3x). Methodology ISCQ 3x was prepared in three following variants: potentized for 2.5 min (i) by application of mechanically performed vertical strokes, or (ii) hand-made vortex-like flows; or (iii) only diluted and not-succussed control. Droplet evaporation method was performed as described in (1); in short: droplets of the three ISCQ 3x variants were evaporated on microscope slides (56 droplets of each variant distributed on four slides were evaporated in one experimental repetition). The experimental setup robustness was monitored by means of positive systematic control experiments, where on all 12 slides droplets of the ISCQ 3x variant potentized by the application of strokes were evaporated. The experiments were repeated five times. The resulting droplet residues were photographed in magnification 100x; the patterns were analyzed by means of the Image J software for their grey level distribution and textural and fractal parameters. Results and discussion All three ISCQ 3x variants could be significantly differentiated regarding some textural and fractal parameters; most parameters differentiated between the variant potentized by means of vertical strokes and the control and vortex-potentized variants. Fractal and textural parameters ranked the samples differently. Control experiments showed a reasonable experimental setup robustness. Conclusion The potentization by performing mechanical strokes vs. hand-made vortex-like flows influenced some phenomenological aspects of droplet evaporation patterns. This might indicate that some changes occurred on substance level as consequence of the mechanical impact. Further studies are necessary in this field.

A method for utilizing automated machine learning for histopathological classification of testis based on Johnsen scores

We examined whether a tool for determining Johnsen scores automatically using artificial intelligence (AI) could be used in place of traditional Johnsen scoring to support pathologists’ evaluations. Average precision, precision, and recall were assessed by the Google Cloud AutoML Vision platform. We obtained testicular tissues for 275 patients and were able to use haematoxylin and eosin (H&E)-stained glass microscope slides from 264 patients. In addition, we cut out of parts of the histopathology images (5.0 × 5.0 cm) for expansion of Johnsen’s characteristic areas with seminiferous tubules. We defined four labels: Johnsen score 1–3, 4–5, 6–7, and 8–10 to distinguish Johnsen scores in clinical practice. All images were uploaded to the Google Cloud AutoML Vision platform. We obtained a dataset of 7155 images at magnification 400× and a dataset of 9822 expansion images for the 5.0 × 5.0 cm cutouts. For the 400× magnification image dataset, the average precision (positive predictive value) of the algorithm was 82.6%, precision was 80.31%, and recall was 60.96%. For the expansion image dataset (5.0 × 5.0 cm), the average precision was 99.5%, precision was 96.29%, and recall was 96.23%. This is the first report of an AI-based algorithm for predicting Johnsen scores.