1
|
Lacerda MM, Silva JC, Vieira AT, Clarindo WR. Cytogenetic Characterization of Passiflora megacoriacea K.Port.-Utl. Employing Image Cytometry. CYTOLOGIA 2019. [DOI: 10.1508/cytologia.84.353] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Melina Marchiorio Lacerda
- Laboratory of Cytogenetics and Plant Tissue Culture, Center for Agricultural Sciences and Engineering, Federal University of Espírito Santo
| | - Jéssica Coutinho Silva
- Laboratory of Cytogenetics and Cytometry, Department of General Biology, Federal University of Viçosa
| | - Ariane Tonetto Vieira
- Laboratory of Cytogenetics and Plant Tissue Culture, Center for Agricultural Sciences and Engineering, Federal University of Espírito Santo
| | | |
Collapse
|
2
|
Silva JC, Carvalho CR, Clarindo WR. Updating the maize karyotype by chromosome DNA sizing. PLoS One 2018; 13:e0190428. [PMID: 29293613 PMCID: PMC5749775 DOI: 10.1371/journal.pone.0190428] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 12/14/2017] [Indexed: 12/20/2022] Open
Abstract
The karyotype is a basic concept regarding the genome, fundamentally described by the number and morphological features of all chromosomes. Chromosome class, centromeric index, intra- and interchromosomal asymmetry index, and constriction localization are important in clinical, systematic and evolutionary approaches. In spite of the advances in karyotype characterization made over the last years, new data about the chromosomes can be generated from quantitative methods, such as image cytometry. Therefore, using Zea mays L., this study aimed to update the species' karyotype by supplementing information on chromosome DNA sizing. After adjustment of the procedures, chromosome morphometry and class as well as knob localization enabled describing the Z. mays karyotype. In addition, applying image cytometry, DNA sizing was unprecedentedly measured for the arms and satellite of all chromosomes. This way, unambiguous identification of the chromosome pairs, and hence the assembly of 51 karyograms, were only possible after the DNA sizing of each chromosome, their arms and satellite portions. These accurate, quantitative and reproducible data also enabled determining the distribution and variation of DNA content in each chromosome. From this, a correlation between DNA amount and total chromosome length evidenced that the mean DNA content of chromosome 9 was higher than that of chromosome 8. The chromosomal DNA sizing updated the Z. mays karyotype, providing insights into its dynamic genome with regards to the organization of the ten chromosomes and their respective portions. Considering the results and the relevance of cytogenetics in the current scenario of comparative sequencing and genomics, chromosomal DNA sizing should be incorporated as an additional parameter for karyotype definition. Based on this study, it can be affirmed that cytogenetic approaches go beyond the simple morphological description of chromosomes.
Collapse
Affiliation(s)
- Jéssica Coutinho Silva
- Laboratório de Citogenética e Citometria, Departamento de Biologia Geral, Centro de Ciências Biológicas e da Saúde, Universidade Federal de Viçosa, Viçosa–MG, Brazil
| | - Carlos Roberto Carvalho
- Laboratório de Citogenética e Citometria, Departamento de Biologia Geral, Centro de Ciências Biológicas e da Saúde, Universidade Federal de Viçosa, Viçosa–MG, Brazil
| | - Wellington Ronildo Clarindo
- Laboratório de Citogenética, Departamento de Biologia, Campus Alegre, Universidade Federal do Espírito Santo, Alegre–ES, Brazil
| |
Collapse
|
3
|
Carella F, De Vico G, Landini G. Nuclear morphometry and ploidy of normal and neoplastic haemocytes in mussels. PLoS One 2017; 12:e0173219. [PMID: 28282459 PMCID: PMC5345825 DOI: 10.1371/journal.pone.0173219] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 02/17/2017] [Indexed: 01/03/2023] Open
Abstract
Haemic neoplasia (HN) in bivalves has been reported in association with mass mortality events in various species of molluscs. The aim of this work was to quantify the nuclear morphometry and DNA content of neoplastic cells of mussels Mytilus galloprovincialis affected by HN using nuclear densitometry in Feulgen-stained preparations. The results were also compared with a population of normal mussel haemocytes. We captured 256 images of 3 different neoplasia stages and 120 images of normal haemocytes; thus, a total of 120,166 nuclei were analysed. We extracted 21 morphological parameters from normal and neoplastic nuclei. Eighteen of these parameters were different (P<0.05). Among those (expressed in pixel units—inter-pixel distance of 0.45 micrometres—as: normal vs. neoplastic) nuclear area (117.1±94.1 vs. 423.1±226.9), perimeter (44.9±14.0 vs. 79.0±21.3) and (IOD) integrated optical density (13.47±34.5 vs. 177.1±150.8) were relevant features to discriminate between normal and neoplastic cells. Those differences allowed identifying two distinctive populations of neoplastic nuclei, occasionally in the same individuals at a given phase of the disease. Moreover, neoplastic haemocytes in less extended lesions showed a ploidy value of 6.2 n along with the presence of a second population of circulating cells with a DNA content of 10.7n. In samples with moderate disease only one peak at 7n was observed. Finally, in more severe conditions, a further ploidy peak of 7.8n was recorded, accompanied by a shallow but broad peak of 31n. This latter extreme value is thought to be due to the presence of giant multinucleated cells where individual nuclei overlap in space and cannot be discerned individually. Computer-based imaging allowed the direct visualization of the cell populations and simultaneous collection of ploidy data as well as morphological features of nuclei.
Collapse
Affiliation(s)
- Francesca Carella
- Department of Biology, University of Naples Federico II, Naples, Italy
- * E-mail:
| | - Gionata De Vico
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Gabriel Landini
- School of Dentistry, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B5 7EG, United Kingdom
| |
Collapse
|
4
|
Duarte CEM, Carvalho CR, Silva-Filho ALD. Adaptation of image cytometry methodology for DNA ploidy analysis of cervical epithelium samples: a pilot study. Taiwan J Obstet Gynecol 2015; 53:227-31. [PMID: 25017273 DOI: 10.1016/j.tjog.2014.04.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 02/05/2014] [Indexed: 01/31/2023] Open
Abstract
OBJECTIVE To determine DNA ploidy in the cervical specimens of patients revealing a suspicion of cancer by image analysis performed by using a combination of commercial analysis software, conventional microscopy, and certified filters. MATERIALS AND METHODS This study followed a prospective design. Cervical samples were obtained from 20 patients undergoing routine screening in the Gynecologic-Oncology Unit of the University Hospital of the Federal University of Minas Gerais, Brazil. Three slides were prepared for each case and the DNA content was determined by image cytometry, post Feulgen staining. DNA ploidy, as well as events exceeding 5C and 9C, was assessed according to the guidelines and algorithms prescribed for diagnostic interpretation by the European Society for Analytical Cellular Pathology. RESULTS By employing the adapted tool, identification of the lesions with euploid and aneuploid profiles was possible. Abnormal DNA content was found in 65% of the cases (13/20), with 45% (9/20) presenting nuclei with >5C content and 20% (4/20) with >9C content. In the analyses conducted in this study, the coefficient of variation with respect to DNA quantity was lower than the 5% threshold recommended by the European Society for Analytical Cellular Pathology. CONCLUSION Image cytometry of the cervical specimens revealed DNA aneuploidy, most probably resulting from chromosomal alterations and appearing as precancerous lesions in 65% of the cases. The adaptations implemented in this study, enabled the DNA-image cytometry to become more accessible, enhancing its extended use as an adjuvant strategy for the early screening of the cervical epithelium samples during routine analyses.
Collapse
Affiliation(s)
- Christiane Eliza Motta Duarte
- Laboratório de Citogenética e Citometria, Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Carlos Roberto Carvalho
- Laboratório de Citogenética e Citometria, Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil.
| | - Agnaldo Lopes da Silva-Filho
- Departamento de Obstetrícia e Ginecologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| |
Collapse
|
5
|
Okotrub KA, Surovtsev NV, Semeshin VF, Omelyanchuk LV. Raman spectroscopy for DNA quantification in cell nucleus. Cytometry A 2014; 87:68-73. [DOI: 10.1002/cyto.a.22585] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 09/28/2014] [Accepted: 10/14/2014] [Indexed: 11/08/2022]
Affiliation(s)
- K. A. Okotrub
- Institute of Automation and Electrometry; Siberian Branch of the Russian Academy of Sciences; Novosibirsk 630090 Russia
| | - N. V. Surovtsev
- Institute of Automation and Electrometry; Siberian Branch of the Russian Academy of Sciences; Novosibirsk 630090 Russia
- Novosibirsk State University; Pirogova-2 Novosibisk 630090 Russia
| | - V. F. Semeshin
- Institute of Molecular and Cellular Biology, Siberian Branch of the Russian Academy of Sciences; Novosibirsk 630090 Russia
| | - L. V. Omelyanchuk
- Novosibirsk State University; Pirogova-2 Novosibisk 630090 Russia
- Institute of Molecular and Cellular Biology, Siberian Branch of the Russian Academy of Sciences; Novosibirsk 630090 Russia
| |
Collapse
|
6
|
Pichugin YG, Semiyanov KA, Chernyshev AV, Palchikova IG, Omelyanchyuk LV, Maltsev VP. Peculiarities of cytometrical methods of DNA content determination in the nucleus. ACTA ACUST UNITED AC 2012. [DOI: 10.1134/s1990519x12030091] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
7
|
Praça-Fontes MM, Carvalho CR, Clarindo WR. C-value reassessment of plant standards: an image cytometry approach. PLANT CELL REPORTS 2011; 30:2303-12. [PMID: 21850594 DOI: 10.1007/s00299-011-1135-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 07/02/2011] [Accepted: 08/02/2011] [Indexed: 05/11/2023]
Abstract
Image cytometry (ICM) has been used to measure DNA 2C-values by evaluating the optical density of Feulgen-stained nuclei. This optical measurement is carried out using three basic tools: microscopy, digital video camera, and image analysis software. Because ICM has been applied to plants, some authors have remarked that studies should be performed before this technique can be accepted as an accurate method for determination of plant genome size. Based on this, the 2C-value of eight plants, which are widely used as standards in DNA quantifications, was reassessed in a cascade-like manner, from A. thaliana through R. sativus, S. lycopersicum, Glycine max, Z. mays, P. sativum, V. faba, to A. cepa. The mean 2C-values of all plants were statistically compared to the values reported by other authors using flow cytometry and/or ICM. These analyses demonstrated that ICM is an accurate and reliable method for 2C-value measurement, representing an attractive alternative to flow cytometry. Statistical comparison of the results also indicated Glycine max 'Polanka' as the most adequate primary standard. However, distinct authors have been advised that 2C DNA content of the reference standard should be close to that of the sample. As three further approaches also revisited the 2C-value of these eight plants, we have thus proposed a mean 2C-value for each eight species.
Collapse
Affiliation(s)
- Milene Miranda Praça-Fontes
- Laboratório de Microscopia, Departamento de Produção Vegetal, Centro de Ciências Agrárias, Universidade Federal do Espírito Santo, CEP 29500-000, Alegre, ES, Brazil
| | | | | |
Collapse
|
8
|
Ruiz-Ruano FJ, Ruiz-Estévez M, Rodríguez-Pérez J, López-Pino JL, Cabrero J, Camacho JPM. DNA amount of X and B chromosomes in the grasshoppers Eyprepocnemis plorans and Locusta migratoria. Cytogenet Genome Res 2011; 134:120-6. [PMID: 21389690 DOI: 10.1159/000324690] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/29/2010] [Indexed: 11/19/2022] Open
Abstract
We analyzed the DNA amount in X and B chromosomes of 2 XX/X0 grasshopper species (Eyprepocnemis plorans and Locusta migratoria), by means of Feulgen image analysis densitometry (FIAD), using previous estimates in L. migratoria as standard (5.89 pg). We first analyzed spermatids of 0B males and found a bimodal distribution of integrated optical densities (IODs), suggesting that one peak corresponded to +X and the other to -X spermatids. The difference between the 2 peaks corresponded to the X chromosome DNA amount, which was 1.28 pg in E. plorans and 0.80 pg in L. migratoria. In addition, the +X peak in E. plorans gave an estimate of the C-value in this species (10.39 pg). We next analyzed diplotene cells from 1B males in E. plorans and +B males in L. migratoria (a species where Bs are mitotically unstable and no integer B number can be defined for an individual) and measured B chromosome IOD relative to X chromosome IOD, within the same cell, taking advantage of the similar degree of condensation for both positively heteropycnotic chromosomes at this meiotic stage. From this proportion, we estimated the DNA amount for 3 different B chromosome variants found in individuals from 3 E. plorans Spanish populations (0.54 pg for B1 from Saladares, 0.51 pg for B2 from Salobreña and 0.64 for B24 from Torrox). Likewise, we estimated the DNA amount of the B chromosome in L. migratoria to be 0.15 pg. To automate measurements, we wrote a GPL3 licensed Python program (pyFIA). We discuss the utility of the present approach for estimating X and B chromosome DNA amount in a variety of situations, and the meaning of the DNA amount estimates for X and B chromosomes in these 2 species.
Collapse
Affiliation(s)
- F J Ruiz-Ruano
- Departamento de Genética, Universidad de Granada, Granada, España
| | | | | | | | | | | |
Collapse
|
9
|
Carvalho CR, Clarindo WR, Abreu IS. Image cytometry: nuclear and chromosomal DNA quantification. Methods Mol Biol 2011; 689:51-68. [PMID: 21153786 DOI: 10.1007/978-1-60761-950-5_4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Image cytometry (ICM) associates microscopy, digital image and software technologies, and has been particularly useful in spatial and densitometric cytological analyses, such as DNA ploidy and DNA content measurements. Basically, ICM integrates methodologies of optical microscopy calibration, standard density filters, digital CCD camera, and image analysis softwares for quantitative applications. Apart from all system calibration and setup, cytological protocols must provide good slide preparations for efficient and reliable ICM analysis. In this chapter, procedures for ICM applications employed in our laboratory are described. Protocols shown here for human DNA ploidy determination and quantification of nuclear and chromosomal DNA content in plants could be used as described, or adapted for other studies.
Collapse
Affiliation(s)
- Carlos Roberto Carvalho
- Laboratory of Cytogenetic and Cytometry, Department of General Biology, Federal University of Viçosa, Viçosa, MG, Brazil.
| | | | | |
Collapse
|
10
|
Mendonça MAC, Carvalho CR, Clarindo WR. DNA content differences between male and female chicken (Gallus gallus domesticus) nuclei and Z and W chromosomes resolved by image cytometry. J Histochem Cytochem 2010; 58:229-35. [PMID: 19875846 PMCID: PMC2825488 DOI: 10.1369/jhc.2009.954727] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Accepted: 10/16/2009] [Indexed: 11/22/2022] Open
Abstract
Chicken red blood cells (CRBCs) are widely used as standards for DNA content determination. Cytogenetic data have shown that the Z sex chromosome is approximately twice as large as the W, so that the DNA content differs to some extent between male (ZZ) and female (ZW) chickens. Despite this fact, male and female CRBCs have been indiscriminately used in absolute genome size determination. Our work was conducted to verify whether the DNA content differences between male and female Gallus gallus domesticus "Leghorn" nuclei and ZZ/ZW chromosomes can be resolved by image cytometry (ICM). Air-dried smears stained by Feulgen reaction were used for nuclei analysis. Chicken metaphase spreads upon Feulgen staining were analyzed for obtaining quantitative information on the Z and W chromosomes. Before each capture session, we conducted quality control of the ICM instrumentation. Our results from nuclear measurements showed that the 2C value is 0.09 pg higher in males than in females. In chromosomes, we found that the Z chromosome shows 200% more DNA content than does the W chromosome. ICM demonstrated resolution power to discriminate low DNA content differences in genomes. We suggest prudence in the general use of CRBC 2C values as standards in comparative cytometric analysis.
Collapse
|
11
|
Clarindo WR, Carvalho CR. Comparison of the Coffea canephora and C. arabica karyotype based on chromosomal DNA content. PLANT CELL REPORTS 2009; 28:73-81. [PMID: 18841372 DOI: 10.1007/s00299-008-0621-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2008] [Revised: 09/22/2008] [Accepted: 09/22/2008] [Indexed: 05/26/2023]
Abstract
Nuclear genome size has been measured in various plants, seeing that knowledge of the DNA content is useful for taxonomic and evolutive studies, plant breeding programs and genome sequencing projects. Besides the nuclear DNA content, tools and protocols to quantify the chromosomal DNA content have been also applied, expanding the data about genomic structure. This study was conducted in order to calculate the Coffea canephora and Coffea arabica chromosomal DNA content, associating cytogenetic methodologies with flow cytometry (FCM) and image cytometry (ICM) tools. FCM analysis showed that the mean nuclear DNA content of C. canephora and C. arabica is 2C = 1.41 and 2.62 pg, respectively. The cytogenetic methodology provided prometaphase and metaphase cells exhibiting adequate chromosomes for the ICM measurements and karyogram assembly. Based on cytogenetic, FCM and ICM results; it was possible to calculate the chromosomal DNA content of the two species. The 1C chromosomal DNA content of C. canephora ranged from 0.09 (chromosome 1) to 0.05 pg (chromosome 11) and C. arabica from 0.09 (chromosome 1) to 0.03 pg (chromosome 22). The methodology presented in this study was suitable for DNA content measuring of each chromosome of C. canephora and C. arabica. The cytogenetic characterization and chromosomal DNA content analyses evidenced that C. arabica is a true allotetraploid originated from a cross between Coffea diploid species. Besides, the same analyses also reinforce that C. canephora is a possible progenitor of C. arabica.
Collapse
|
12
|
de Abreu IS, Carvalho CR, Clarindo WR. Chromosomal DNA content of sweet pepper determined by association of cytogenetic and cytometric tools. PLANT CELL REPORTS 2008; 27:1227-1233. [PMID: 18347800 DOI: 10.1007/s00299-008-0539-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Revised: 02/29/2008] [Accepted: 03/06/2008] [Indexed: 05/26/2023]
Abstract
The nuclear DNA content of sweet pepper (Capsicum annuum L. var. annuum, 2n = 24) has been measured by flow and image cytometries but the DNA content of each chromosome of this species has not yet been regarded. DNA content of individual chromosomes has been quantified by the flow karyotyping technique, which requires a great quantity of intact metaphasic chromosomes and methods that allow the characterization of individual chromosomes; however, the obtainment of adequate number of metaphases can be difficult in some species like C. annuum. In order to estimate the DNA content of each C. annuum var. annuum cv. "New Mexican" chromosome, flow and image cytometries were associated with the cytogenetic methodology. First, the DNA amount (2C = 6.90 pg) was established by flow cytometry. Integrated optical density (IOD) values were calculated by image cytometry for each Feulgen stained metaphasic chromosome. Then, by distributing the correspondent metaphasic value (4C = 13.80 pg) proportionally to average IOD values, the following chromosomal DNA contents were obtained in pg: 0.74 (chromosome 1), 0.67 (2), 0.61 (3, 4), 0.60 (5), 0.59 (6, 7), 0.58 (8), 0.57 (9), 0.56 (10) and 0.39 (11, 12). This study reports an alternative and reproducible technique that makes quantifying the chromosomal DNA content possible.
Collapse
Affiliation(s)
- Isabella Santiago de Abreu
- Laboratório de Citogenética e Citometria, Departamento de Biologia Geral, Universidade Federal de Viçosa, Av. PH Rolfs, s/n, Viçosa, Minas Gerais CEP 36570-000, Brazil
| | | | | |
Collapse
|
13
|
Maounis NF, Chorti M, Apostolakis E, Ellina E, Blana A, Aggelidou M, Dritsas I, Markidou S. Prognostic impact of Deoxyribonucleic acid (DNA) image analysis cytometry and immunohistochemical expression of Ki67 in surgically resected non-small cell lung cancers. ACTA ACUST UNITED AC 2006; 30:507-14. [PMID: 17113721 DOI: 10.1016/j.cdp.2006.07.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/14/2006] [Indexed: 11/21/2022]
Abstract
BACKGROUND The aim of the present study was to evaluate the prognostic significance of DNA ploidy and Ki67 expression in non-small cell lung carcinoma (NSCLC). METHODS This prospective study included 96 patients with stages I-IIIA NSCLC who underwent surgical excision. DNA image analysis cytometry was applied on imprints. Calculation of the DNA index (DI) and the 5c exceeding rate (5cER) was performed and the histograms were classified as peridiploid, peritetraploid, and x-ploid-multiploid. The Ki67 immunoreactivity was determined according to the avidin-biotin complex immunoperoxidase method. RESULTS DNA histogram classification disclosed 30 peridiploid cases, 15 peritetraploid and 51 x-ploid-multiploid. Forty-eight cases (50%) had 5cER > 5%. The Ki67 immunoreactivity was below 25% in 53 tumors (62.4%) and above 25% in 32 (32.6%). Our results revealed the existence of a statistically significant relationship of DNA ploidy with nodal status (p = 0.042) and grade (p = 0.005). Adenocarcinomas and large cell carcinomas were more frequently encountered in x-ploid-multiploid tumors as compared to squamous cell carcinomas, which were more frequently peridiploid (p = 0.003). 5cER showed statistically significant association with nodal status (p = 0.037). Univariate analysis with respect to survival revealed significant association with stage (p < 0.001), nodal status (p < 0.001), tumor status (p < 0.001), DNA ploidy (p = 0.008) and 5cER (p = 0.0124). Multivariate analysis revealed stage and ploidy status as independent factors: peridiploid tumors were associated with better survival as compared to x-ploid-multiploid tumors (p = 0.022). CONCLUSION Our results suggest that DNA ploidy, as determined by image analysis, provides an independent prognostic parameter for patients with NSCLC and thus, could be used to identify a subset of patients with more aggressive tumors.
Collapse
Affiliation(s)
- Nicoletta F Maounis
- Department of Cytology, Sismanoglion General Hospital, 1 Sismanogliou Str., Athens 151 26, Greece.
| | | | | | | | | | | | | | | |
Collapse
|
14
|
Ogielska M, Kierzkowski P, Rybacki M. DNA content and genome composition of diploid and triploid water frogs belonging to the Rana esculenta complex (Amphibia, Anura). CAN J ZOOL 2004. [DOI: 10.1139/z04-188] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Central European water frog Rana esculenta L., 1758 is a natural hybrid between Rana lessonae Camerano, 1882 (LL) and Rana ridibunda Pallas, 1771 (RR). Hybrids are usually diploid (RL) or triploid (LLR or RRL). Distinguishing LL from RL, RR from RL, and LLR from RRL according to external morphology is ambiguous. In this study we checked whether the DNA content in erythrocyte nuclei measured by image cytometry is useful in determination of the taxonomic status of diploids (LL, RR, and RL) and the genome composition of triploids (LLR and RRL). For exact and direct identification of parental species, as well as for determination of genome composition in hybrids, we applied actinomycin D – 4',6-diamidino-2-phenylindole chromosome staining to metaphase plates. We analyzed 43 LL, 12 RR, and 32 RL diploids, and 37 LLR and 19 RRL triploids. All diploid hybrids had 2n = 26 chromosomes, and all triploid hybrids had 3n = 39 chromosomes. Neither aneuploid nor mosaic hybrids were detected. The expected numbers of 13 R. lessonae (L) and 13 R. ridibunda (R) chromosomes in RL hybrids were recorded in about 31% of individuals. In the rest of the sample the composition was variable, ranging from 9 to 14 R chromosomes and the corresponding number of L chromosomes. The expected composition of 26 L and 13 R chromosomes was detected in about 32% of LLR triploids, whereas in the rest of the sample the composition of chromosomes ranged from 8 to 15 R chromosomes and the corresponding number of L chromosomes. The expected numbers of 26 R and 13 L chromosomes were detected in about 26% of RRL triploids, whereas in the rest of the sample the composition of chromosomes ranged from 19 to 28 R chromosomes and the corresponding number of L chromosomes. The DNA content densitometry showed that RR and RL diploids had 9.5% and 3.8% more DNA, respectively, than LL diploids. These differences, although statistically significant, were not sufficient to unequivocally discriminate LL from RL and RR from RL. Triploids had about 50% more DNA than LL diploids (49% in LLR and 51% in RRL), but these differences were too small for unequivocal determination of their genome composition.
Collapse
|
15
|
Hardie DC, Gregory TR, Hebert PDN. From pixels to picograms: a beginners' guide to genome quantification by Feulgen image analysis densitometry. J Histochem Cytochem 2002; 50:735-49. [PMID: 12019291 DOI: 10.1177/002215540205000601] [Citation(s) in RCA: 148] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The study of genome size variation is important from a number of practical and theoretical perspectives. For example, the long-standing "C-value enigma" relating to the more than 200,000-fold range in eukaryotic genome sizes is best studied from a broad comparative standpoint. Genome size data are also required in detailed analyses of genome structure and evolution. The choice of future genome sequencing projects will be dependent on knowledge regarding the sizes of genomes to be sequenced, and so on. To date, genome size data have been acquired primarily by Feulgen microdensitometry or flow cytometry. Each has several advantages but also important limitations. In this review, we provide a practical guide to the new technique of Feulgen image analysis densitometry. The review is designed for those interested in genome size measurements but not extensively experienced in histochemistry, densitometry, or microscopy. Therefore, relevant historical and technical background information is included. For easy reference, we provide recipes for required reagents, guidelines for cell staining, and a checklist of steps for successful image analysis. We hope that the accuracy, rapidity, and cost-effectiveness of Feulgen image analysis demonstrated here will stimulate further surveys of genome sizes in a variety of taxa.
Collapse
Affiliation(s)
- David C Hardie
- Department of Zoology, University of Guelph, Guelph, Ontario, Canada
| | | | | |
Collapse
|
16
|
van der Laak JAWM, Siebers AG, Cuijpers VMJI, Pahlplatz MMM, de Wilde PCM, Hanselaar AGJM. Automated identification of diploid reference cells in cervical smears using image analysis. CYTOMETRY 2002; 47:256-64. [PMID: 11933016 DOI: 10.1002/cyto.10078] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Acquisition of DNA ploidy histograms by image analysis may yield important information regarding the behavior of premalignant cervical lesions. Accurate selection of nuclei for DNA measurement is an important prerequisite for obtaining reliable data. Traditionally, manual selection of nuclei of diagnostic and reference cells is performed by an experienced cytotechnologist. In the present study, a method for the fully automated identification of nuclei of diploid epithelial reference cells in Feulgen- restained Papanicolaou (PAP) smears is described. METHODS The automated procedure consists of a decision tree implemented on the measurement device, containing nodes with feature threshold values and multivariate discriminant functions. Nodes were constructed to recognize debris and inflammatory cells, as well as diploid and nondiploid epithelial cells of the uterine cervix. Evaluation of the classifier was performed by comparing resulting diploid integrated optical densities with those from manually selected reference cells. RESULTS AND CONCLUSION On average, automatically acquired values deviated 2.4% from manually acquired values, indicating that the method described in this paper may be useful in cytometric practice.
Collapse
|