Ploidy and fruit trait variation in oil-tea Camellia:Implications for ploidy breeding

Plant polyploidy often occurs in conjunction with higher yield and superior quality.Therefore,obtaining polyploid germplasms is a significant part of breeding.The oil-tea Camellia tree is an important native woody plant that produces high-quality edible oil and includes many species of Camellia with different ploidies.However,whether higher ploidy levels in oil-tea Camellia trees are related to better traits remains unclear.In this study,the ploidy levels of 30 different oil-tea Camellia strains in three different species in the Sect.Paracamellia were determined by flow cytometry and chromosome preparation,and the phenotypic characteristics and fatty acid compositions of the fruits were examined by field observations and laboratory analyses.The correlations between the ploidy level of oil-tea Camellia and the main traits of the fruit were investigated.Our results showed that 10 Camellia lanceoleosa strains were diploid,10 Camellia meiocarpa strains were tetraploid and 10 Camellia oleifera strains were hexaploid.Hexaploid C.oleifera had larger fruit size and weight,more seeds per fruit,greater seed weight per fruit,higher oil content and greater yield per crown width than tetraploid C.meiocarpa and diploid C.lanceoleosa,but their fruit peel thickness and fresh seed rate were significantly lower,and these traits were significantly correlated with ploidy level.In addition,in terms of fatty acid composition,hexaploid C.oleifera had a higher oleic acid content than tetraploid C.meiocarpa and diploid C.lanceoleosa,but their linoleic acid,linolenic acid and arachidonic acid contents were lower.The contents of palmitic acid,stearic acid and total unsaturated fatty acids were not significantly correlated with ploidy level.In conclusion,certain correlations exist between the main characteristics of oil-tea Camellia fruit and the ploidy level,and increasing the ploidy level led to an increase in fruit yield with no effect on oil composition.The discovery of variations in the main characteristics of oil-tea Camellia fruit with different ploidies will facilitate germplasm innovation and lay a foundation for ploidy breeding and mechanistic research on fruit traits.

Clinical application of DNA ploidy to cervical cancer screening: A review

Screening for cervical cancer with DNA ploidy assessment by automated quantitative image cytometry has spread throughout China over the past decade and now an estimated 1 million tests per year are done there. Compared to conventional liquid based cytology, DNA ploidy has competitive accuracy with much higher throughput per technician. DNA ploidy has the enormous advantage that it is an objective technology that can be taught in typically 2 or 3 wk, unlike qualitative cytology, and so it can enable screening in places that lack sufficient qualified cytotechnologists and cytopathologists for conventional cytology. Most papers on experience with application of the technology to cervical cancer screening over the past decade were published in the Chinese language. This review aims to provide a consistent framework for analysis of screening data and to summarize some of the work published from 2005 to the end of 2013. Of particular interest are a few studies comparing DNA ploidy with testing for high risk human papilloma virus(hrH PV) which suggest that DNA ploidy is at least equivalent, easier and less expensive than hrH PV testing. There may also be patient management benefits to combining hr HPV testing with DNA ploidy. Some knowledge gaps are identified and some suggestions are made for future research directions.

DNA ploidy analysis and expression of MMP-9, TIMP-2, and E-cadherin in gastric carcinoma

AIM： To investigate DNA ploidy and expression of MMP-9, TIMP-2, and E-cadherin in gastric carcinoma and to explore the mechanism of invasion and metastasis of gastric carcinoma. METHODS： Immunohistochemical methods were used to detect the expressions of MMP-9, TIMP-2, and E-cadherin in 156 cases, including 99 cases of gastric carcinoma, 16 cases of adjacent noncancerous mucosa, 16 cases of distant metastases and 25 cases of metastatic lymph node （LN） from gastric carcinoma. Flow cytometry DNA ploidy and S-phase fraction （SPF） analysis were performed on 57 cases, including 47 cases of gastric cancer, 6 cases of adjacent noncancerous mucosa, and 4 cases of distant metastatic cancer. RESULTS： The expression of MMP-9 was significantly correlated with Lauren＇s classification, Borrmann＇s classification, LN metastasis, tumor metastasis, and TNM stage, as well as depth of invasion （all P〈0.05）. The positive rate was lower in noncarcinoma than in carcinoma （31.3% vs 66.7%, P〈0.01）. The expression of TIMP-2 was significantly correlated with Borrmann＇s classification, LN metastasis, and the depth of invasion （all P〈0.05）. The expression of E-cadherin was significantly correlated with differentiation, Lauren＇s classification, Borrmann＇s classification, and LN metastasis, as well as the depth of invasion （P〈0.01 or P〈0.05）. E-cadherin was less expressed in carcinoma than in noncarcinoma （42.4% vs 87.5%, P〈0.01）. There was a positive correlation between MMP-9and TIMP-2 and a negative correlation between MMP-9 and E-cadherin, but no correlation between TIMP-2 and E-cadherin. Also there was a positive correlation between DNA aneuploid rate and differentiation and LN metastasis. SPF that was higher than 15% was positively correlated with tumor size, differentiation and LN metastasis. And there was a significant difference between carcinoma and noncarcinoma in DNA aneuploid rate and SPF. CONCLUSION： With tumor progression and development of heterogeneity, the abnormal expressions of MMP-9, TIMP-2, and E-cadherin or DNA aneuploid rate or high SPF gradually increases, suggesting that they play a crucial role in gastric carcinoma progression. 2005 The WJG Press and Elsevier Inc. All rights reserved

Relationship between DNA ploidy, expression of ki-67 antigen and gastric cancer metastasis

AIM To evaluate the relationship between the expression of Ki 67 antigen and the pathobiological behaviours of gastric cancers especially their distant metastases. METHODS Fifty six specimens of gastric cancer routinely fixed in formalin and embedded in paraffin (FFEP) were studied by immunohistochemical method. RESULTS Expression of Ki 67 antigen was significantly related to the distant metastases to liver, ovary and adrenal gland ( P <0 005), but not related to the histological type, growth pattern, depth of invasion, histological differentiation and the metastases to local lymph nodes ( P >0 05). Furthermore, the Ki 67 antigen expression was significantly related to the DNA aneuploidy pattern, which is closely related to poor prognosis ( P <0 05). CONCLUSION Overexpression of Ki 67 can be used as an objective marker of the proliferative activity for predicting prognosis of gastric cancer and metastatic potential to distant organs.

Analysis of DNA Ploidy, Cell Cycle and Ki67 Antigen in Nasopharyngeal Carcinoma by Flow Cytometry

Summary: The expression of DNA ploidy, the cell cycle and Ki67 antigen in nasopharyngeal carcinoma (NPC) were studied and their relationship with the clinical biological behaviors and prognosis of NPC was evaluated. Biopsied specimens of NPC were made into cell suspension. By using cytometric double labeling Ki67 and DNA method, the expression of DNA ploidy, the cell cycle and Ki67 antigen were analyzed. The patients were followed-up for about 3 years and the relationship between the above-mentioned parameters and the clinical biological behavior and prognosis of NPC were evaluated. Of the 62 cases of NPC, the DNA aneuploid accounted for 29.03 %. The S phase cells accounted for 0 to 54 % in the cell cycle and the positive expression of Ki67 ranged from 0 to 52 %. There were 40 cases of LPI (64.5 %) including 15 negative cases and 22 cases of HPI (35 5 %) respectively. The DNA anueploid content was positively related to the S phase cells. The patients having a low expression of Ki67 or DNA aneuploid in tumor cells were not sensitive to chemotherapy, liable to metastasis to distant organs and had a poor prognosis, while Ki67 showed no correlation with DNA ploidy and the cell cycle. It was suggested that DNA ploidy and Ki67 could be used as an independent and objective marker to evaluate the radiosensitivity and prognosis of NPC.

DNA ploidy and c-Kitmutation in gastrointestinal stromal tumors

AIM: To investigate the prognostic significance of c-Kitgen emutation and DNA ploidy in gastointestinal stromal tumors (GISTs).METHODS: A total of 55 cases of GISTs were studied for the expression of c-Kit by immunohistochemistry, and the c-Kit gene mutations in exons 9, 11, 13, and 17 were detected by polymerase chain reaction-single strand confirmation polymarphism (PCR-SSCP) and denaturing high performance liquid chromatography (D-HPLC) techniques. DNA ploidy was determined by flow cytometry.RESULTS: Of the 55 cases of GISTs, 53 cases (96.4%) expressed c-Kit protein. The c-Kit gene mutations of exons 11 and 9 were found in 30 (54.5%) and 7 cases (12.7%),respectively. No mutations were found in exons 13 and 17.DNA aneuploidy was seen in 10 cases (18.2%). The c-Kit mutation positive GISTs were larger in size than the negative GISTs. The aneuploidy tumors were statistically associated with large size, high mitotic counts, high risk groups, high cellularity and severe nuclear atypia, and epithelioid type.There was a tendency that c-Kit mutations were more frequently found in aneuploidy GISTs.CONCLUSION: DNA aneuploidy and c-Kit mutations can be considered as prognostic factors in GISTs.

Morphological characteristics of leaf epidermis and size variation of leaf,flower and fruit in different ploidy levels in Buddleja macrostachya (Buddlejaceae)

Buddleja macrostachya （Buddlejaceae） is a widespread shrub native to the Sino-Himalayan mountains and beyond. It has been found to occur at two ploidy levels, hexaploid, 2n=6x=114 and dodecaploid, 2n= 12x=228. To determine if morphological characters might be used as indicators of ploidy levels, we measured floral and fruit length, relative and absolute leaf size, trichome density on both leaf surfaces, and stomatal density and length in different populations orB. macrostachya. In general, flower and fruit length, absolute leaf size, and stomatal length in,eased with an increase at ploidy level （P〈0.01）, whereas adaxial cell and stomatal density decreased with an increase at ploidy level （P〈0.01）. We found no conspicuous differences in relative leaf size （P〉0.05） in different populations. Other characters studied such as trichome type, cuticular membrane and ornamentation of stomata, cell and stomatal shape, and anticlinal wall pattern were quite constant in this species. Thus it appears that flower and fruit length, absolute leaf size, and stomatal frequency and length can be used to distinguish hexaptoid from dodecaploid cytotypes either in the field or in herbarium specimens.

Physiological and molecular characteristics of two ploidy mutants in Myrica rubracv.Dongkui

In this study, two ploidy mutant lines ofMyrica rubra cv. Dongkui （DK） were identiifed and named as DB1 and DB2. The lforal organ, leaf cel structure, ploidy, and number of chromosomes of the two mutants were investigated. Meanwhile, anthocyanin contents at different developmental stages were analyzed, and the Cy-3-glu contents of DB1 and DB2 at the ful ripe stages are signiifcantly higher than that of DK by 27.84 and 23.51%, respectively. Furthermore, 6 RNA libraries at two developmental stages （young fruit stage and ful ripe stage） were built for RNA-Seq. By mapping to the reference database, 28407, 28043, and 28683 genes were detected in the young fruit of DB1, DB2, and DK, respectively, while 28040, 22256, and 27351 genes were detected in the ful ripe stage, respectively. There were 281 differentialy expressed genes between DB1 and DK, with 123 and 158 genes up-regulated and down-regulated, respectively, and 47 differentialy expressed genes between DB2 and DK, of which 8 and 39 genes were up-regulated and down-regulated. Using real-time PCR, the expression levels of the eight functional genes at different developmental stages of the fruit were also analyzed. These comprehensive analyses showed that both mutants are different from DK, which is the result of natural doubling of ploidy, thereby generating a pleiotropic effect. As we known, it is the ifrst report to study the relationship between bayberry ploidy alterations and genes involved in regulation of fruit mutations, which wil help to identify the morphological and cytological characteristics ofM. rubragermplasm, and provide a theoretical basis and technical support for genetic improvement and creation of breeding resources.

DNA PLOIDY，EXPRESSION OF p53 PROTEIN AND METASTATIC BEHAVIOUR OF GASTRIC CARCINOMA

DNA ploidy of 57 gastric carcinomas with metastases(12 liver,1 adrenal,4 ovary and 48 lymph node) were measured by flow cytometry.DNA anueploidy was significantly related to liver metastases:9 out of 12 gastric carcinomas with liver metastases were anueploid(75%) as compared to 13 out of 45(28.8%) of cases without liver metastases(P<0.01);the one gastric carcinoma with adrenal metastasis was also anueploid.DNA ploidy was not related to ovarian or lymph node metastases.Another interesting finding was that all of 3 gastric carcinomas with liver metastases which showed a diploid DNA pattern,expressed p53 protein, while all of 3 carcinomas with liver metastases but no p53 protein expression were anueploid.The expression of p53 protein was not related to ovarian metastases.The results suggested that an anueploid DNA pattern and the expression of p53 protein are both objective markers valuable in predicting high risk potential of metastases to the liver,and that the combined detection of these markers can be a most useful method in the follow-up of Patients with gastric carcinoma in detecting those at high risk of developing metastases following surgical resection.Also the poorer prognosis of Patients with gastric carcinoma showing an anueploid DNA pattern may be related to the development of distant organ metastases through the blood vascular system.Furthermore,the clone of gastric carcinoma cells which accumulate p53protein or show an anueploid DNA pattern may have a causative role in the development of liver(&.adrenal) metastases.

Study on the Relationship Between the Ploidy Level of Microspore-Derived Plants and the Number of Chloroplast in Stomatal Guard Cells in Brassica oleracea

The relationship between the ploidy level of microspore-derived plants and chloroplast number in stomatal guard cells was studied in cabbage, broccoli, and Chinese kale. In the experiment, distribution statistics analysis and t-test were used to perform statistical analysis on chloroplast number of different ploidy level in those stomatal guard cells mentioned above, and morphology identifying and chromosome counting were used to test accuracy of counting chloroplast number in stomatal guard cells. The chloroplast average number in stomatal guard cells was very similar among the different leaf positions on the same plant and among significantly among the different ploidy the different locations in the same stoma in the same variety. All the leaf, while the chloroplast number varied distributions of the chloroplast number in different ploidy stoma were normal distribution fitted. A correlation has been established between ploidy and chloroplast number in the stomatal guard cells. In every single stoma of microspore-derived plants, the chloroplast number for a haploid should not be more than 10, diploids 11 to 15, and polyploids more than 15. The accuracy of this method for identification of different ploidy plants was 93.93%. Furthermore, the accuracy of this method was reliable and did not vary with the plants growth conditions. Therefore, the chromosome ploidy of plants derived from microspore culture in cabbage, broccoli, and Chinese kale can be identified by simply counting the chloroplast number in stomatal guard cells.

Effect of ploidy level on expression of lycopene biosynthesis genes and accumulation of phytohormones during watermelon(Citrullus lanatus) fruit development and ripening

The difference between lycopene and phytohormone levels among diploid, triploid and tetraploid plants of two watermelon cultivars during fruit growth and ripening was studied. The expression pattern of five genes（phytoene synthase（PSY1）, phytoene desaturase（PDS）, ζ-carotene desaturase（ZDS）, carotenoid isomerase（CRTISO）, and lycopene β-cyclase（LCYB）） was analyzed in details. In red-fleshed cultivar Mimei, lycopene content increased rapidly from 25 to 35 days after pollination（DAP）, and then decreased at 40 DAP. Triploid and tetraploid fruit had higher levels of lycopene than diploid. Moreover, triploid tended to contain more lycopene than tetraploid during fruit growth and ripening stages. However, little amount of lycopene（0–2 mg kg–1 fresh weight（FW）） in yellow-fleshed cultivar Huangmei was found during all fruit development stages. In Mimei, transcript level of PSY1 was generally higher than the other four genes, and LCYB gene expression was the lowest among all five genes being tested. PSY1, CRTISO and LCYB genes showed higher transcript levels in polyploid than in diploid fruit. By contrast, in Huangmei, transcript level of LCYB was not the lowest, but only lower than that of PSY1. PSY1, CRTISO and LCYB genes showed higher expression levels in diploid than in polyploid fruit. In Mimei, the negative correlation between gibberellane（GA） content and lycopene accumulation was determined in all three different ploidy fruits, while a positive correlation was observed between abscisic acid（ABA） content and lycopene accumulation only in diploid watermelon. These results indicated that different lycopene contents in different ploidy watermelons is regulated by the differential transcription expression of the lycopene metabolic genes and phytohormones.

Characterization of ploidy levels in Chrysanthemum L. by flow cytometry

Analyzing the ploidy levels of plants is important for identifying species, selecting parental lines, identifying the relationships between species, and determining evolutionary patterns. The genus Chrysanthemum is widely distributed throughout the world and exhibits different ploidy levels. We used flow cytometry to analyze the ploidy levels of nine species of Chrysanthemum L. collected from different regions and geographical locations in China. Three diploids from Henan and Wuhan provinces corresponded to Chrysanthe- mum lavandulifolium and two species of C. nankingense, while three tetraploids from various regions corresponded to C. indicum and two species of C. chanetii. Two hexaploids corresponding to C. vestitum were collected at Funiu moun- tain （Henan province）, and C. zawadskii was collected at Huangshan mountain （Anhui province）. We found that OTTO extraction buffer was suitable for extracting nuclei from most species, apart from C. zawadskii. Flow cytometry proved to bea simple, rapid, and highly accurate method for identifying ploidy levels in Chrysanthemum species.

THE CLINICAL PATHOLOGY AND DNA PLOIDY OF GASTRICMUCOSA ASSOCIATED LYMPHOID TISSUE (MALT)LYMPHOMA INFILTRATING THE LEIOMYOMASOF THE UTERUS

Objective: To investigate the clinicopathology and DNA ploidy of gastric mucosa associated lymphoid tissue (MALT) lymphoma infiltraving the leiomyomas of the uterus of a patient. Methods: The routine paraffin slides were cut, stained with HE, immunochemically by ABC methodusing the and stained by Feulgen method. Then the DNA ploidy of tumor cells was measured with an image cytometer. Results: In the mucosa, submucosa and the smooth muscle layer of the stomach and in the leiomyomas of the uterus there was diffusive and dense infiltration of centrocyte-like cells. The DNA measurement results were that the distribution of DNA mass of lymphoma cells in stomach and in lymph nodes had a single main aneuploidy peak each, and the distribution of DNA mass of lymphoma cells in leiomyomas of uterus had two peaks; one of them was the diploid, the other aneuploid. Conclusion: The MALT lymphoma cell invasion in uterus must be differentiated with a primary lymphoma in the uterus, the chronic lymphocyte leukemia in uterus and an endometrial stromal sarcoma. The present prognosis of the patient under discussion was poor. The follow-up results indicated the DNA index seemed to be important for predicting the malignancy degree and prognosis.

PROGNOSTIC SIGNIFICANCE OF DNA PLOIDY IN PATIENTS WITH STAGE II COLORECTAL CANCER

Objective: To evaluate the relationship between flow cytometric DNA ploidy, biological features and prognosis in patients with Stage II colorectal cancer. Methods: Nuclear DNA content, proliferation index and S-phase fraction were measured in a prospective series of 45 patients with curatively resected Stage II colorectal adenocarcinomas by means of flow cytometry using frozen tumor samples. Results: Of the 45 samples examined, 17 tumors (38%) were diploid and 28 (62%) aneuploid. The diploid tumors were significantly more common in the proximal colon than in the distal colon (67% vs. 23%; P<0.01). There was no correlation between DNA ploidy and the other clinicopathological variables (P>0.05). The proliferation index and S-phase fraction in the distal tumors were higher than those in the proximal tumors, but the difference was not significant (P>0.05). When the 5-year survival rate of patients with Stage II colorectal cancer was compared by the log rank test, a significant relationship between DNA ploidy status and disease free survival was observed in the group of all patients. Patients with DNA diploid tumors had a better disease free survival than those with DNA aneuploid tumors (P<0.05). Conclusion: These findings support that DNA ploidy status, proliferation index and S-phase fraction may differ in the proximal and distal colorectal cancer. Flow cytometric DNA ploidy status might be a useful prognostic factor in patients with Stage II colorectal cancer.

DNA PLOIDY AND p53 EXPRESSION ASSOCIATED WITH TUMOR SITE AND LYMPH NODE METASTASIS IN COLORECTAL CANCER

Objective: To study the association of DNA ploidy abnormality and p53 overexpression with the carcinogenesis of colorectal cancer. Methods: DNA ploidy and p53 expression were measured in a series of 42 colorectal adenocarcinomas by means of flow cytometry and immunohistochemical test. Results: 17 tumors (40%) were diploid and 25 (60%) aneuploid. The aneuploid tumors were significantly more common in the distal colon than in the proximal colon (P<0.01). Aneuploidy was significantly associated with lymph node metastasis (P<0.05). There was no correlation between DNA ploidy and the other clinicopathological variables. Of the 22 samples examined, the positive rate of p53 expression was 59% (13/22). p53 expression was more frequently observed in the distal tumors (11/13) than in the proximal tumors (2/9) (P<0.05). Conclusion: Our data support the hypothesis that the carcinogenesis of colorectal cancer might differ in proximal and distal tumors. DNA ploidy abnormality and p53 overexpression may play an important role in the development of distal colorectal cancer.

Correlative Study on the Expression of p53 and DNA Ploidy in Acute Nonlymphocytic Leukemia

We used the flow cytometric immunoassay to study the correlation between the tumor-suppressor gene product p53- and the DNA ploidy in 30 de novo cases of acute nonlymphocytic leukemia (ANLL).The results showed that 15 cases were negative and the other 15 cases were positive expression for p53. As compared with p53 negative (p53) cases, the patients with positive p53 (p53+) had higher percentage of bone marrow blasts and lower peripheral leukocyte and platelet counts,which had no influence on the complete remission rate. Before treatment, DNA diploidy was seen in 18 cases including 12 p53- cases, and DNA aneuploidy in 12 cases including 9 p53+. After therapy, aneuploidy could be transformed into diploidy.Patients with P53+ or having aneuploidy in complete remission were at risk for early relapse. We believe that p53 may be involved in the process of leukemogenesis and progression of ANLL.

Identification of Candidate Genes Related to Polyploidy and/or Apomixis in <i>Eragrostis curvula</i>

This work was aimed at identifying genes that show altered expression profiles in response to changes in ploidy and/or reproductive mode (from sexual to apomictic) in the African grass Eragrostis curvula. A differential display analysis was performed on leaf and flower transcriptomes from a series of genetically related euploid plants, including tetraploid apomictic, diploid sexual, and tetraploid sexual plants. More than 100 primer combinations were used to generate 11,864 total markers, yielding 1293 differential bands. Of these bands, 11.84% to 6.74% were related to ploidy and 0.71% to 2.17% to the reproductive mode, depending on the tissue. A small percentage of bands showed similar expressions between the tetraploid apomictic and the diploid sexual plants. Expression-based similarity dendrograms were constructed. Our data suggested that ploidy is more decisive than tissue type in defining the transcriptome structure. Out of 102 fragments sequenced, 50 showed strong homology to known genes. The differentially expressed genes were mapped in silico onto maize chromosomes. Several candidates mapped within the linkage group syntenic to the Tripsacum dactyloides diplospory-governing region. The evidence indicates that expression of genes located around the diplospory-associated region may be strongly influenced by ploidy and may be silenced in the apomictic genotype. These findings are discussed in the context of diplospory molecular control and its connection with ploidy.

Studies on the Morphologic Characteristics and Economic Traits of Different Ploidy Materials of Ramie

Different ploidy ramie materials were studied via microscopic observation on stem sections and macerated fiber cells. Morphologic differences between different ploidy plants were analyzed. Average bark area percentages in ramie stem transection of haploids, tetraploids, diploids and triploids were 28. 91, 27. 05, 26. 97 and 24.77% respectively. Average percentages of fiber layer area of diploids, haploids, tetraploids and triploids were 16.80, 16. 58, 15.52 and 13.78% respectively. Average fiber cell diameter and cell wall thickness were increased along with the increase of the ploidy of the plants. Average fiber length of diploids, triploids and haploids were 8. 49, 7. 96 and 6. 93 cm respectively. Average L/B (length/breadth) of diploids, triploids and haploids were 2 470. 7, 2 390. 6 and 1 616.3 respectively. Average breadths of fiber of haploids, diploids and triploids were 29. 30, 33. 87 and 49. 20μm respectively. However, there were relatively large variations in the above characteristics among the ramie materials of the same ploidy levels. Field performance of different ploidy plants was also investigated. As the chromosome ploidy increasing, there was a tendency of declining in shoot number per plant and increasing in stem diameter. Average shoots per plant of haploids, diploids, triploids and tetraploids were 5.83, 5.30, 3.77 and 3. 65 whereas their average stem diameters were 0.66, 0. 67, 0. 74 and 0. 76 cm respectively. Triploids were the tallest, while haploids were the shortest. Triploids had strong growth vigour, diploids and tetraploids had moderate growth vigour, while haploids appeared to be lack of growth vigour. Cold stress tolerance of tetraploids were the strongest, diploid had the moderate tolerance, while haploids and triploids were the least tolerant to cold stress. Both haploids and triploids were sterile.

Correlated Flow Cytometric Analysis of H－ras p21 and DNA Ploidy in Acute Myelogenous Leukemia

The flow cytometric immunoassay was used to study the correlation between the H-ras oncogene product p21 and the DNA ploidy in 30 de novo cases of acute myelogenous leukemia (AML). The results showed that 17 cases were negative for p21 expression and 13 positive for p21. The patients with positive p21 had higher percentage of bone marrow and peripheral blasts and lower peripheral leukocyte count. The expression of p21 had no influence on the therapeutic effect. Before treatment,DNA diploidy occurred in 18 cases including 13 p21 negative ones,and DNA aneuploidy was revealed in 12 cases including 8 p21 positive ones. Patients with positive p21 or having aneuploidy in complete remission were at risk for early relapse. Our results suggest that p21 may be involved in the process of leukemogenesis and progression in AML.

Screening the Best Material for Ploidy Identification of Sugarcane-related Genera

[Objectives] Flow cytometry is widely used to identify plant chromosome ploidy because of its simplicity, rapidity and accuracy. Chromosome ploidy identification is an important part of sugarcane ploidy breeding and application research. It is particularly important to find out the best detection part for ploidy identification in sugarcane. [Methods] The cell suspensions of sugarcane stem tips and leaves were prepared by blade chopping method. The cell suspensions were detected by flow cytometry. The best position for ploidy identification was determined by comparing the cell suspension prepared from stem tips and cell suspension prepared from leaves. [Results] The results showed that the cell suspension dissociated from stem tips was more clear than that from leaf cell suspension;the proportion of non-adherent cells in the suspension prepared from stem tips was larger than that from the leaf cell suspension;the main peak of the stem tip cell suspension was single and the number of cells was more than that of the stem tip cell suspension by flow cytometry. Using the known ploidy ‘Badilar’ as the internal reference, the ploidy of cyathomi 87-16 was detected to be 8.37. [Conclusions] Sugarcane shoot tips are an ideal material for ploidy identification. This study provides a theoretical basis for selecting the best detection site for ploidy identification of sugarcane.