Ki67 index is now an essential part of classification of pancreatic neuroendocrine tumors. However, its adaptation into daily practice has been fraught with challenges related to counting ...methodology. In this study, three reviewers used four counting methodologies to calculate Ki67 index in 68 well-differentiated pancreatic neuroendocrine tumors: (1) 'eye-ball' estimation, which has been advocated as reliable and is widely used; (2) automated counting by image analyzer; (3) manual eye-counting (eye under a microscope without a grid); and (4) manual count of camera-captured/printed image. Pearson's correlation (R) was used to measure pair-wise correlation among three reviewers using all four methodologies. Average level of agreement was calculated using mean of R values. The results showed that: (1) 'eye-balling' was least expensive and fastest (average time <1 min) but had poor reliability and reproducibility. (2) Automated count was the most expensive and least practical with major impact on turnaround time (limited by machine and personnel accessibility), and, more importantly, had inaccuracies in overcounting unwanted material. (3) Manual eye count had no additional cost, averaged 6 min, but proved impractical and poorly reproducible. (4) Camera-captured/printed image was most reliable, had highest reproducibility, but took longer than 'eye-balling'. In conclusion, based on its comparatively low cost/benefit ratio and reproducibility, camera-captured/printed image appears to be the most practical for calculating Ki67 index. Although automated counting is generally advertised as the gold standard for index calculation, in this study it was not as accurate or cost-effective as camera-captured/printed image and was highly operator-dependent. 'Eye-balling' produces highly inaccurate and unreliable results, and is not recommended for routine use.
Counting mitoses: SI(ze) matters Cree, Ian A.; Tan, Puay Hoon; Travis, William D. ...
Modern pathology,
09/2021, Letnik:
34, Številka:
9
Journal Article
Recenzirano
Odprti dostop
Mitoses are often assessed by pathologists to assist the diagnosis of cancer, and to grade malignancy, informing prognosis. Historically, this has been done by expressing the number of mitoses per n ...high power fields (HPFs), ignoring the fact that microscope fields may differ substantially, even at the same high power (×400) magnification. Despite a requirement to define HPF size in scientific papers, many authors fail to address this issue adequately. The problem is compounded by the switch to digital pathology systems, where ×400 equivalent fields are rectangular and also vary in the area displayed. The potential for error is considerable, and at times this may affect patient care. This is easily solved by the use of standardized international (SI) units. We, therefore, recommend that features such as mitoses are always counted per mm2, with an indication of the area to be counted and the method used (usually “hotspot” or “average”) to obtain the results.
As part of routine histological grading, for every invasive breast cancer the mitotic count is assessed by counting mitoses in the (visually selected) region with the highest proliferative activity. ...Because this procedure is prone to subjectivity, the present study compares visual mitotic counting with deep learning based automated mitotic counting and fully automated hotspot selection. Two cohorts were used in this study. Cohort A comprised 90 prospectively included tumors which were selected based on the mitotic frequency scores given during routine glass slide diagnostics. This pathologist additionally assessed the mitotic count in these tumors in whole slide images (WSI) within a preselected hotspot. A second observer performed the same procedures on this cohort. The preselected hotspot was generated by a convolutional neural network (CNN) trained to detect all mitotic figures in digitized hematoxylin and eosin (H&E) sections. The second cohort comprised a multicenter, retrospective TNBC cohort (n = 298), of which the mitotic count was assessed by three independent observers on glass slides. The same CNN was applied on this cohort and the absolute number of mitotic figures in the hotspot was compared to the averaged mitotic count of the observers. Baseline interobserver agreement for glass slide assessment in cohort A was good (kappa 0.689; 95% CI 0.580–0.799). Using the CNN generated hotspot in WSI, the agreement score increased to 0.814 (95% CI 0.719–0.909). Automated counting by the CNN in comparison with observers counting in the predefined hotspot region yielded an average kappa of 0.724. We conclude that manual mitotic counting is not affected by assessment modality (glass slides, WSI) and that counting mitotic figures in WSI is feasible. Using a predefined hotspot area considerably improves reproducibility. Also, fully automated assessment of mitotic score appears to be feasible without introducing additional bias or variability.
Introduction: One of the ways of human exposure to aluminum (Al) is Al food packaging materials and cookwares. Although many studies have examined the biotic influence of nanoparticles or ionic form ...of heavy metals, there are limited studies conducted on the possible health risks of metals in the form of alloy used for making utensils. In this study, the effect of water boiled in Al cookwares with defined concentrations of Al on the genomic abnormalities and cell division of meristematic cells of onion root was evaluated using Allium cepa assay.
Materials and Methods: The onion roots were treated with water boiled in Al utensils (three pots) with different concentrations of Al (5 and 10 mg/l) for 42 to 43 hours and then analyzed for mitotic index (MI) and mitotic phase aberrations (MPA).
Results: The percent of MI in the study groups treated with 5 mg/l of Al from pot 1 and 10 mg/l from all pots increased significantly compared to the control group (P < 0.05). Also, the frequency of total MPA in all Al treated groups significantly increased compared to the control group (P < 0.05). The most significant results were derived by sticky chromosomes, anaphase bridge, going ahead chromosome and disturbed mitosis, respectively.
Conclusion: The result of this study confirmed the genotoxic effect of water boiled in Al cookwares containing the examined range of Al concentrations on the meristematic cells of onion root.
- This paper aims to enhance our understanding of the effects of ionizing radiation using radiobiology and biodosimetry techniques applied to living plant organisms. Plants are particularly suitable ...for this purpose as they are highly sensitive to detecting potential genotoxic agents in the environment and their use allows us to avoid using animals in research in compliance with the 3R principle. Currently, the onion (Allium cepa) is recognized as a valid model for the analysis of environmental pollutants but has been relatively unexplored as an indicator of radiation exposure. In this study, analyses of the genotoxicity of X and alpha radiation were conducted using the micronucleus test and mitotic index analysis. Our results indicate that Allium cepa can be considered a valid alternative model to animal use for assessing the effects of ionizing radiation. In particular, it was found that alpha radiation caused significant damage, as evidenced by an increased number of micronuclei, which was 20 times higher compared to X-ray radiation. This was further confirmed through the observation of the effective dose parameter, as determined by the analysis of various weight factors associated with different types of radiation.
•Onion (Allium cepa) serves as a model for studying the effects of ionizing radiation.•The micronucleus assay evaluates genotoxicity of X and alpha radiation.•The correlation between radiation dose and onion damage is studied.
In this study, we examined the response of Allium cepa sprout stem cells, or meristems, to UVB and UVC radiation. The choice of Allium cepa, or onion, was made to avoid the controversial use of ...animal models. Allium cepa is a well-established in vivo standard model that is frequently used in cytogenetic research connected to various environmental contaminants. Indicators such as micronuclei and chromosomal abnormalities were used to evaluate the genotoxicity of UVB and UVC radiation, and the mitotic index was used to investigate the cytotoxicity of the radiation, providing information on cellular proliferation. The Shapiro-Wilk test (p < 0.05) confirmed the normality of the data. The analysis of the Pearson linear correlation coefficient (r = 0.97), conducted across all dose points considered, including the negative control, revealed an almost perfect positive linear relationship between the dose and the number of cells with micronuclei, for both UVB and UVC. The frequency of induction of micronuclei as a function of dose for both radiation types was found to be similar. However, a difference in the morphology of the cells exposed to UVB radiation compared to those exposed to UVC radiation was observed. In conclusion, the mitotic index analysis showed no significant differences in cell activity between UVC and UVB irradiation compared with control samples. The results from this study support the use of Allium cepa and cytogenetic endpoints as a biodosimetric method for ultraviolet radiation.
•Allium Cepa has been used as a biodosimetric model for UV radiation.•Assessment of UVB-UVC genotoxicity through micronuclei and chromosomal aberrations.•A difference in the type of damage induced by UVB and UVC radiation has been observed.
Since the appearance of COVID-19 at the end of December 2019 in Wuhan, China,
and its prevalence in many countries, the symptoms of this disease extended from
respiratory problems to a wide range of ...symptoms associated with the invasion of
the virus to many organs and tissues in the body of patients. The white blood cells,
particularly T lymphocytes, are the main effectors in defense against viral infections. This study was performed to investigate the response of white blood cells to
the infection of SARS-COV-2 at the early stage of the disease. T cells decreased
in number in the circulation, but this decrease was not associated with an impairment of their activity. Moreover, stimulation of virus-infected T cells with nonspecific mitogen revealed increased cell proliferation. This study concluded that T
lymphocytes are highly activated during SARS-COV-2 infection, despite lymphopenia, at least at the early stages of the disease.
Keywords: COVID-19, lymphocyte proliferation, mitotic index
Due to their multifunctionality and the numerous fields of applicability, insects are extensively studied today for both their biomedical and nutritional properties. In the current study the ...cytogenotoxic and antimicrobial potential of ethanol and methanol extracts of Nezara viridula (Linnaeus 1758) was evaluated using the Allium test, respectively the disk diffusion test. A mitostimulatory effect of the extracts of N. viridula and a variation of the cytogenotoxic activity of the extracts in a gender-dependent manner was noticed. As well, significant variations of the mitotic index were determined through the type of solvent used and the concentration of the extracts. High frequency chromosomal aberrations and mitotic abnormalities were recorded with high concentration ethanolic extracts. Following the testing of four standard bacterial strains and two standard yeast strains, a slightly antimicrobial activity was observed when compared to control. The use of invasive species in such studies opens up new perspectives on the potential of organisms considered harmful.
For many centuries, the treatment with medicinal plants was the only means accessible to various ethnic groups, and nowadays plants are still widely used in the treatment of diseases, besides being ...the raw material for several drugs. However, many of these plants may present unknown genotoxic effects, making their consumption a health risk. Species such as Malva parviflora L. have been used by the general population for medicinal purposes: antifungal, anti-inflammatory, analgesic, and antioxidant. This study had the objective of analyzing the cytogenotoxic potential of aqueous extracts of this Malva species using the Allium cepa test, which serves as a bioindicator of the genotoxicity of plant extracts. Forty-four seedlings of M. parviflora were grown for 36 days between November and December 2020, in a greenhouse in two groups: half of the plants were protected with a shading screen, and the rest were not. The aqueous extracts were prepared from the aerial part and roots (fresh and dehydrated), at the concentration of 5 g L-¹. The bulbs of A. cepa were left for 24 hours in the treatments, plus the negative (distilled water) and positive (glyphosate 1.5%) treatments. The roots of the bulbs were collected, placed in the fixative for 24 hours, transferred to 70% alcohol, and stored in a refrigerator. The slides were prepared by the crushing technique, and cells in the division and with chromosome alteration were analyzed, mitotic and genotoxic index were calculated, and statistical analysis was done by the Chi-square and Scott-Knott tests. From the results obtained, it is possible to conclude that the aqueous extracts of M. parviflora at a concentration of 5 g L-¹ present antiproliferative activity, but are not genotoxic. The cultivation mode is relevant, that is, with and without shading the fresh leaves present a difference in cell proliferation, but the same does not occur with the dried leaves.
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