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PubMed2005

Selection for phenotypic divergence between diploid and autotetraploid Heuchera grossulariifolia.

Much of the diversity of flowering plants is associated with genomic duplication through polyploidy. Little is known, however, about the evolutionary mechanisms responsible for the diversification of novel polyploid lineages. We evaluated the possibility that divergence is driven by natural selection by estimating the strength of phenotypic selection acting on three floral traits in sympatric populations of diploid and autotetraploid Heuchera grossulariifolia over three years. Our results demonstrate consistent directional selection for increasing scape length and floral display in both diploid and tetraploid populations. In contrast, selection acting on flowering phenology varied across year and ploidy. Specifically, selection was found to favor late-flowering diploids in 2001 and 2002 but early-flowering tetraploids in 2003. We investigated the mechanistic basis of divergent selection for flowering phenology in 2003 by estimating the relationship between plant flowering phenology and the probability of intercytotype pollinator movement. The results demonstrated that less divergent tetraploids were significantly more likely to experience intercytotype flights than were more divergent tetraploids. This result is consistent with the pattern of phenotypic selection observed. Taken together, our results suggest that divergence of polyploids and their diploid progenitors may be driven by a process analogous to reinforcement whereby selection favors phenotypes that reduce the probability of intercytotype matings with reduced fertility.

Flowers↗

PubMedDate not supplied

[Several characteristics of new strains of diploid green marmoset fibroblasts].

Two strains of diploid fibroblasts were derived from green monkey fetal lungs and their main properties were studied. These strains were shown not to differ principally from the well studied human diploid fibroblasts. The derived cultures are free from contaminating viruses. The titers of attenuated poliomyelitis virus strains achieved in green monkey diploid cells are comparable to those in primary cultures of green monkey kidneys. The possiblity of using green monkey diploid fibroblasts in virological practice is discussed.

Animals↗

PubMed1989

[Aneuploid and diploid neoplasms of the breast and their relation to the prognosis of the disease].

Flow cytofluorometry has been used to examine the tumor ploidy in 32 patients with benign mammary tumors and 41 patients with mammary carcinomas; the relationship between the tumor ploidy and the disease prognosis has been under study. Chicken red cells whose DNA content is invariable and is almost 3 times lower were used as the inner reference sample for diploid cells. All the obtained DNA histograms of benign mammary tumors were diploid (the DNA index 1), those of malignant tumors aneuploid in 26 (63%) and diploid in 15 (37%) cases. Analysis of the late results of treatment has shown that the process progress is significantly more often in the patients with the aneuploid DNA content in the tumor cells (chi 2 = 10.2; p less than 0.01), this progress being due to delayed metastases to the lymph nodes, bones, and viscerae; the 5-year survival rate is lower (chi 2 = 4.19; p less than 0.05) than in diploid malignant tumors.

Breast Neoplasms↗

PubMedDate not supplied

[Relation of the radiosensitivity of yeast cells to the LET of the radiation. Experiments with diploid cells].

A study was made of the dependence of radiosensitivity D0-1 of diploid yeast cells on linear energy transfer L of radiation, and the obtained results were analyzed in terms of the previously developed model concepts. A diploid-specific repair of radiation damages was shown to be equally effective with different L. This mode of repair had no direct effect on D0-1 (L) function. The observed contribution of the diploid-specific repair to cell radioresistance decreased with increasing L. This, however, was due to physical and geometric factors rather than to the decreased efficiency of diploid-specific repair.

Alpha Particles↗

PubMed1988

[Kinetics of protein degradation in diploid and trisomic human fibroblasts].

The degradation rate of long-lived and short-lived proteins was determined in diploid fibroblasts and fibroblasts with trisomy 7 derived from human embryos. Two fractions of proteins were detected in the exponentially growing diploid fibroblasts with half-lives (T 1/2) 37 and 19 hours. The rate of protein degradation increases in diploid fibroblasts as they approach confluence and protein fractions with T 1/2 30, 18 and 12 hours appear. The rate of protein degradation in trisomic fibroblasts does not change for the long-lived and short-lived proteins and is the same in both exponential (T 1/2 31 and 14 hours) and stationary phase (T 1/2 33 and 17 hours). The relative amount of the short-lived proteins in trisomic fibroblasts in the stationary phase decreased as compared with the one in diploid fibroblasts. It is apparent that a mechanism of regulation of protein catabolism in trisomic fibroblasts is impaired.

Cells, Cultured↗

PubMed1986

Rubini, a new live attenuated mumps vaccine virus strain for human diploid cells.

A new, live attenuated mumps vaccine virus strain for human diploid cells has been developed at the Swiss Serum and Vaccine Institute, Berne. The Rubini virus was derived from a child of the same name possessing typical clinical signs and symptoms of mumps infection. Attenuation of the wild virus was performed by isolation and serial passage in WI-38 human diploid cells, specific pathogen-free hens' eggs and MRC-5 human diploid cells. The attenuated virus has been examined in respect of identity, freedom from adventitious agents and growth potential in MRC-5 cells. Furthermore, it does not evoke any clinical reactions in either baby or adult monkeys. It is characterized by the production in Vero cells of smaller plaques than are elicited by either the Jeryl Lynn or Urabe mumps virus strains. The reactogenicity and immunogenicity of the Rubini virus for man was studied by administering a monovalent vaccine to 13 adult male volunteers and a trivalent human diploid cell Rubini, measles (Edmonston-Zagreb-19 virus strain) and rubella (RA 27/3 virus strain) vaccine to 60 children ranging in age from 15 to 24 months. No reactions were observed. Seroconversion was obtained in 95% of the vaccinees, who developed a mean 50% neutralizing antibody titre of 1:64 after 6-8 weeks. Sensitization to avian and other animal proteins and antibiotics which may follow the use of most of the currently available measles-mumps-rubella vaccines, either single or combined, may be expected to be eliminated when this new vaccine is used. Its use in persons already sensitized to such products should furthermore induce no anaphylactic reactions.

Adult↗

PubMed1985

[Mutability of the LYS2 gene in diploid saccharomycete yeasts. I. The occurrence of spontaneous mutants and mutants induced by x-ray and ultraviolet radiation].

More than 3000 spontaneous and induced lys2 mutants were obtained in haploid and diploid strains of yeast Saccharomyces. The ability to utilize alpha-aminoadipate was used for lys2 mutant screening. The spontaneous and induced mutation rates were measured in haploid and diploid strains. Mitotic segregation of pho1 marker linked to LYS2 was studied in lys2 mutants obtained in diploid strains. Fertility of diploid lys2 mutants was tested. The conclusion to be drawn from the data presented is that mutations appeared in one of two homologous chromosomes and then segregated by mitotic homozygotization.

Diploidy↗

PubMed1979

Management of 41 persons exposed to a rabid dog: unplanned experience with human diploid vaccine.

Thirty-six persons -- veterinarians, technicians and students at a veterinary clinic -- were unwittingly exposed to a rabid dog over a period of 21/2 days. One veterinarian received a penetrating bite, two other individuals were grabbed by the dog but the skin was not penetrated, and many were exposed to saliva or urine or both. In addition, the owner of the dog and his wife and three children, while not bitten, were exposed to saliva. The diagnosis was made post mortem when specimens of the dog's brain were examined by indirect fluorescent antibody testing. All but one of the students had been vaccinated against rabies with hamster kidney vaccine, but eight members of the veterinary college's staff had not been so vaccinated. Treatment started with duck embryo vaccine; if necessary, rabies (human) immune globulin was also given. When one student reacted severely to the first dose of duck embryo vaccine permission was sought to bring a human diploid vaccine into Canada. In five patients the human diploid vaccine was substituted for the duck embryo vaccine because of severe reactions to the latter. Twenty-five staff members and the family of five received both vaccines. Reactions to the human diploid vaccine were minor and transient. Recommendations include the early licensing of the human diploid vaccine in Canada.

Adult↗

PubMedDate not supplied

[Formation of diploids by Aspergillus niger and their biosynthesis of citric acid].

Diploid organisms appeared spontaneously in heterokaryons of Aspergillus niger produced by crossing a beige mutant, which was adenine-deficient, and a green mutant requiring the addition of yeast autolysate. The frequency of diploidization increased two-fold under the action of colchicine (0.5%). The diploids became prototrophous, the colour of their conidia increased 1.5--2.4 times. The rate of production of citric acid by the diploid strains which had originated under the action of colchinine was 1.5 times higher than that of the parent haploid mutants.

Aspergillus niger↗

PubMed1984

Diploid gynogenesis in Xenopus laevis and the localization with respect to the centromere of the gene for periodic albinism ap.

Diploid gynogenetic Xenopus laevis were obtained by inseminating the eggs with u.v. irradiated spermatozoa, and treating them with hydrostatic pressure to inhibit the expulsion of the second polar body. A u.v. dose of 3000 ergs/mm2 genetically inactivates the spermatozoa without loss of their ability to activate egg development. The use of a genetic marker on very large samples of eggs made it possible to verify the efficiency of the methods employed. The comparison of the development of diploid gynogenetic embryos with that of haploid gynogenetic, triploid and diploid controls makes it very probable that the relatively high mortality or abnormal development obtained with the pressurized eggs is not due to partial homozygosity but rather to physical damage to the egg structure by this treatment. Altogether about 2500 developing eggs were used. In addition diploid gynogenetic reproduction from females heterozygous for a known mutation allows the mapping of the gene concerned relative to the centromere on the basis of the recombination rate. For this experiment we used the recessive mutation causing periodic albinism (ap) and found the position of this gene to be between 44 map units from the centromere and the end of the chromosome.

Albinism↗

PubMed1984

Influence of injected pluripotential (EK) cells on haploid and diploid parthenogenetic development.

A number of pluripotential embryo-derived EK cells were introduced into the blastocoele of haploid and diploid parthenogenetic embryos which were subsequently transferred to suitable recipients. At autopsy on day 10 or 11 of pseudopregnancy 22% of decidua in the diploid series contained somite-stage embryos while an additional 12% contained abnormal egg cylinder-like sacs. In the haploid series, 7% of the decidua contained somite-stage embryos and an additional 5% contained abnormal 'sacs'. In 'injected' diploid and haploid 'controls' in which the zonae were pierced with an empty injection pipette 3% and 0% respectively of decidua in these two series contained somite-stage embryos, while an additional 17% and 3% respectively of decidua in these two series contained abnormal sacs. GPI analysis revealed that the EK cells were incorporated into somite-stage conceptuses in only one third of the diploids and in none of the haploid embryos. Although the presence of EK cells considerably increases the chance of normal embryonic development taking place, a detectable contribution from the EK cells into the resulting somite-stage embryo is apparently not necessary. Possible mechanisms allowing successful early post-implantation development to occur in this study are discussed.

Animals↗

PubMedDate not supplied

[Respiratory activity of diploid Pullularia pullulans strains].

The activity of respiration was compared among three strains (one haploid strain and two diploid strains) of Pullularia pullulans, in cultures of different age. The strains hardly differed in the intensity of endogenous respiration. During respiration on glucose, the diploid strain of P. pullulans 11254(13) that synthesized pullulan at a higher rate was also characterized by lower rates of oxygen uptake and carbon dioxide evolution per unit biomass as compared to two other strains. In this case, the cells of the diploid strain of P. pullulans 11254(13) had a lower respiration quotient, i.e. they oxidized a lesser part of the substrate to carbon dioxide. As the result, the diploid strain 11254(13) can use a greater portion of the carbon source for pullulan synthesis.

Absorption↗

PubMed1993

[S-phase fraction and malignant potential in DNA diploid colorectal cancer].

Patients with DNA diploid tumor have a significantly longer survival than those with DNA aneuploid in colorectal cancer, but some patients with diploid tumor show poor survival. For assessing malignant potential in diploid colorectal cancer, flow cytometric analysis of S-phase fraction (SPF) was investigated using paraffin-embedded materials from 79 carcinoma patients who had been treated from 1971 to 1989. There was no significant correlation between SPF and clinicopathological factors (such as sex, tumor size, tumor location, macroscopical type, depth of invasion, node metastasis, peritoneal dissemination, liver metastasis and clinical stage). Mean SPF was significantly higher in poorly differentiated type carcinomas than in well differentiated type carcinomas. Patients with higher SPF had a tendency to poorer survival than those with lower SPF. From these results, it was concluded that SPF represents histological differentiation and that SPF may be a prognostic indicator, in diploid colorectal cancer.

Carcinoma↗

PubMed1997

Quality assurance in DNA image analysis on diploid cells.

DNA image analysis is presently performed in many laboratories. Before general extrapolation of results between different laboratories, validation has to be performed for interlaboratory studies on DNA image analysis. The aim of this study was to establish the performance of different DNA image analysis instruments when measuring different diploid cells. On three separate parts of the same object slide, human liver cells, white blood cells, and imprints of a breast fibroadenoma were sampled. In this quality assurance interlaboratory study, 13 laboratories participated voluntarily. Two slides were sent to each participating laboratory: one Feulgen and one unstained to be stained according the participating laboratory in-house procedure. The features integrated optical density (IOD) and object AREA were recorded for each nucleus. For calculation of the results, the average IOD value of liver diploid cells was set at 2c. A striking difference was observed between the different presumed diploid cell types, from almost 1c to 3c. This variation was not dependent on central or in-house staining. Although in-house calibration was performed for each image analysis system, a surprisingly large variation existed in the reported object AREA, irrespective of the cell type. These results clearly demonstrate that measurements performed in one laboratory cannot be extrapolated to the outcome of others and support the need for standardization. The use of external control cells works well for comparison of instruments. In conclusion, in DNA image analysis quality control is necessary, standardization is obligatory, and the use of an internal control for determination of the diploid peak in a histogram of patient samples is recommended.

Breast Neoplasms↗

PubMedDate not supplied

[Protein synthesis in maize haploids and diploids during cultivation under normal conditions and in the presence of phenol].

14C-leucine incorporation in cytoplasmic protein was compared for three haploid forms, three derivative autodiploid lines and four hybrid forms of maize. It has been found that the precursor incorporation in the haploid forms was by 15-20% higher that in appropriate autodiploid lines. However, the level of protein synthesis wes practically the same for all investigated diploid forms. Thus, the increase of the ploidy level correlates with the decrease of the cytoplasmic protein synthesis. It was also shown that the protein content was practically equal in haploid and diploid forms. Proceeding from the authors' data one can conclude that the protein distraction may also have different intensity. The next step of the investigation was the study of the effects of the chemical factor of cytoplasmic protein synthesis in maize seedlings with different ploidy levels in vivo. It has been revealed, that the rate of 14C-leucine incorporation in the cytoplasmic proteins differ for the haploid forms which grew on the Knop media with the addition of phenol (0.05%) and without pollutant. Nevertheless, approximately equal level of 14C-leucine incorporation was observed for autodiploids. Recently it was demonstrated that the synthetic intensity of different RNA fractions is higher in the haploid maize forms than in the diploid ones and that the haploid and diploid forms of maize display the different reaction on phenol pollution. When comparing our data with the published results it is possible to conclude that the hypothesis about the low intensity of metabolism in haploid plants, existing in literature, is not true. The authors suppose that the high activity of synthesis of nuclear, transfer and ribosomal RNA and cytoplasmic proteins in the haploid plants may be connected with high mitotic activity. The authors' data are in agreement with the hypothesis that the ratio of nuclear volume and surface determines the metabolism rate.

Diploidy↗

PubMed1999

Unexpected ratio of allozyme expression in diploid and triploid individuals of the clonal hybrid fish Phoxinus eos-neogaeus.

Phoxinus eos-neogaeus, a North American freshwater fish, was formed by hybridization between P. neogaeus and P. eos. Individuals of P. eos-neogaeus express one allozyme of P. eos and one allozyme of P. neogaeus for enzymes for which the parental allozymes are distinctive. We performed densitometry on phosphoglucomutase (PGM) and one glucose-6-phosphate isomerase locus (GPI-A) separated by cellulose acetate electrophoresis to determine if the parental species' allozymes are expressed in proportion to the number of genomes present in diploid and triploid individuals, and if these enzymes are regulated separately in different tissues. In diploids, activity of the P. eos allozyme was greater than the P. neogaeus allozyme in eye, liver, and muscle but not in heart (one sample t-test, P = 0.05) for PGM. The activity of the P. eos GPI-A allozyme was significantly greater than the P. neogaeus allozyme in heart, eye and muscle but not in liver (one sample t-test, P = 0.05). The expected ratio of eos:neogaeus expression in triploid P. eos-neogaeus x eos individuals is 2:1. For PGM, the observed ratio of eos:neogaeus expression was not significantly different from 2:1 in all four tissues. The P. eos allozyme for GPI was expressed less than expected in all four tissues (one-sample t-test, P = 0.05). Thus, greater than expected expression of the P. eos allozyme was not observed in triploid individuals as it was in the diploids. These data show that PGM and GPI are regulated separately, and that regulation differs by tissue, and in fish of distinct ploidy levels. J. Exp. Zool. 284:663-674, 1999.

Animals↗

PubMed2000

Induction of gynogenesis in muskellunge with irradiated sperm of yellow perch proves diploid muskellunge male homogamety.

Diploid gynogenesis was induced in muskellunge Esox masquinongy using UV-irradiated muskellunge sperm as the first step in producing monosex females. In this approach, we have to rely on negative controls as an indirect reference for sperm genetic material destruction. In the first experiment, equal proportions of gynogenetic females and males were produced. Negative controls, UV-irradiated sperm without heat shock, yielded some normal hatching larvae, described as spontaneous diploids. In the second experiment, muskellunge eggs were activated using sperm from yellow perch. Because hybrids between these species are not viable, we produced unambiguous gynogens. When UV-irradiated yellow perch sperm was used to inseminate muskellunge eggs, haploids resulted (22.5% +/- 2.8% survival to the eyed stage). To produce diploid gynogens, a heat shock of 31 degrees C was applied to inseminated eggs 20 min after activation for a duration of 6 min. This process yielded several hundreds of gynogens for rearing. Several treatments of masculinizing hormone, 17alpha-methyltestosterone (MT), were carried out. Fish were dissected and gonads examined histologically for sex determination. Gynogens produced using yellow-perch sperm confirmed the presence of males in the control group, whereas the MT bath treatment (400 microg/liter) resulted in the production of fish with ovotestis. These results provide evidence for male homogamety in muskellunge and imply that a change of strategy is needed to produce monosex populations.

Animals↗

PubMed1992

Comparison between diploid and aneuploid hepatocellular carcinomas: a flow cytometric study.

Nuclear DNA content of hepatocellular carcinoma (HCC) was estimated by flow cytometry after hepatic resection in 91 patients during the past 5 years. There were 53 diploid and 38 aneuploid tumours. Clinicopathological features were compared retrospectively between the patients with diploid and those with aneuploid HCC. DNA ploidy did not show any correlation with age, sex, alcohol abuse, hepatitis B virus, serum alpha-fetoprotein level or underlying liver disease. Histopathologically, the incidence of HCC less than 2 cm in diameter tended to be higher in the diploid group but no difference was seen for large tumours (greater than 5 cm). The grade of tumour differentiation also tended to be higher in this group of small HCC. The ploidy pattern did not influence the rate of capsule or daughter nodule formation, or venous invasion. There were no significant differences in survival rate or in the incidence and time of intrahepatic tumour recurrence between the two groups. This study may indicate that nuclear DNA ploidy is not a particularly predictive factor for the surgical treatment of HCC.

Aneuploidy↗