FEULGEN HYDROLYSIS: EFFECT OF ACID AND TEMPERATURE

1966 ◽  
Vol 14 (8) ◽  
pp. 601-604 ◽  
Author(s):  
JEROME J. DECOSSE ◽  
NANCY AIELLO

Two methods of Feulgen hydrolysis (5.0 N HCl at room temperature and 1.0. N HCl at 60°C) were examined by serial microspectrophotometric measurements of the relative DNA content of normal human lymphocytes subjected to each hydrolysis. The DNA contents at optimum hydrolysis were equal by both methods. Hydrolysis in 5.0 N HCl at room temperature resulted in an interval of 120 min of stable peak values. Successive hydrolyses to the optimum time, as defined for each methtod in the initial experiment, indicated that hydrolysis 5.0. N HCl at room temperature provided a more reliable technique. The results also suggested that depurination is dependent primarily on acid rather than heat, while further degradation is dependent primarily on heat rather than acid.

Blood ◽  
1953 ◽  
Vol 8 (10) ◽  
pp. 905-915 ◽  
Author(s):  
NICHOLAS L. PETRAKIS

Abstract The DNA content, in arbitrary units, of individual circulating lymphocytes from nine normal subjects, nine patients with chronic lymphocytic leukemia, and five patients with acute lymphocytic leukemia was estimated microspectrophotometrically with the Feulgen dye. Normal circulating lymphocytes were found to contain twice the average DNA content of normal human spermatids, corroborating their diploid chromosome number. Lymphocytes from normal and leukemic lymph node and bone marrow were frequently found possessing four times the average spermatid DNA value. Three out of nine patients with chronic lymphocytic leukemia, and four of five patients with acute lymphocytic leukemia had significantly increased numbers of circulating lymphocytes containing DNA values which were elevated above the normal diploid value. The patients demonstrating cells with elevated DNA values were in a clinically exacerbated phase of their disease. The significance of these findings is discussed.


1985 ◽  
Vol 27 (5) ◽  
pp. 614-616 ◽  
Author(s):  
F. S. Rutherford ◽  
E. W. B. Ward

The fluorochrome 4,6-diamidino-2-phenylindole was used as a stain for nuclear DNA in the fungus Phytophthora megasperma f. sp. glycinea. Measurements of DNA contents were made cytofluorometrically using known haploid and diploid strains of Aspergillus nidulans as standards. No significant differences between DNA levels in nine races of Phytophthora megasperma f. sp. glycinea were found. The results are consistent with genetical data that all nine races are diploid in the vegetative state.Key words: Phytophthora, ploidy, fungi, DNA content, fluorescence.


HortScience ◽  
2009 ◽  
Vol 44 (1) ◽  
pp. 44-48 ◽  
Author(s):  
Irene E. Palmer ◽  
Thomas G. Ranney ◽  
Nathan P. Lynch ◽  
Richard E. Bir

Rudbeckia L. are valuable nursery crops that offer broad adaptability and exceptional ornamental merit. However, there is little information on interspecific and interploid crossability and ploidy levels of specific cultivars. The objectives of this study were to determine the ploidy levels and relative DNA contents (genome sizes) of selected species and cultivars, to evaluate self-compatibility and crossability among species and ploidy levels, and to explore reproductive pathways in triploid R. hirta L. with the goal of facilitating future breeding endeavors and development of new hybrids. Reciprocal interspecific crosses were performed between R. hirta cultivars and R. fulgida Ait., R. missouriensis Engelm. ex C.L. Boynton & Beadle, and R. subtomentosa Pursh. as well as reciprocal interploid crosses among four R. hirta cultivars. A combination of relative DNA content analysis and chromosome counts was used to test for hybridity and to determine ploidy levels for selected species, cultivars, and interploid R. hirta F1 hybrids. Of the specific clones tested, R. subtomentosa and R. missouriensis were diploid, R. fuligida varieties were tetraploid, and R. hirta include both diploid and tetraploid cultivars. Mean 1Cx DNA content varied over 320% among species. The interploid R. hirta crosses produced triploids as well as pentaploids and hexaploids. Seedlings from open-pollinated triploid R. hirta appeared, based on diverse phenotypes and DNA contents, to be aneuploids resulting from sexual fertilization, not apomixis. Of the 844 seedlings from interspecific F1 crosses, only one individual, R. subtomentosa ×R. hirta, had a DNA content intermediate between its parents and was confirmed as the only interspecific hybrid. Although most taxa had low self-fertility, seedlings (with genomic sizes similar to their maternal parent) resulted after interspecific crosspollination, indicating that pseudogamy is one reproductive pathway in Rudbeckia species.


1972 ◽  
Vol 14 (2) ◽  
pp. 347-351 ◽  
Author(s):  
M. H. El-Lakany

Relative DNA content and chromosome number and behaviour were studied in Manitoba wild roses. The hexaploid, Rosa acicularis, contained the largest amount of DNA, about three times that of the diploid, R. woodsii. Another diploid species, R. blanda, contained less DNA than R. woodsii. One specimen, identified as R. blanda with some introgression from R. woodsii, had the same amount of DNA as the latter species. R. × dulcissima, a hybrid between R. blanda and R. woodsii, had DNA contents similar to R. woodsii. The origin of a tetraploid, with DNA contents intermediate between diploid and hexaploid species, and 14 bivalents in diakinesis, was suggested to be hybridization between R. acicularis and a diploid rose. Chromosome behaviour in meiosis and DNA content were used in a discussion of interspecific relationships.


Author(s):  
Bruce Wetzel ◽  
Robert Buscho ◽  
Raphael Dolin

It has been reported that explants of human fetal intestine can be maintained in culture for up to 21 days in a viable condition and that these organ cultures support the growth of a variety of known viral agents responsible for enteric disease. Scanning electron microscopy (SEM) has been undertaken on several series of these explants to determine their appearance under routine culture conditions.Fresh specimens of jejunum obtained from normal human fetuses were washed, dissected into l-4mm pieces, and cultured in modified Leibowitz L-15 medium at 34° C as previously described. Serial specimens were fixed each day in 3% glutaraldehyde for 90 minutes at room temperature, rinsed, dehydrated, and dried by the CO2 critical point method in a Denton DCP-1 device. Specimens were attached to aluminum stubs with 3M transfer tape No. 465, and one sample on each stub was carefully rolled along the adhesive such that villi were broken off to expose their interiors.


1963 ◽  
Vol 09 (01) ◽  
pp. 030-052 ◽  
Author(s):  
Eberhard Mammen

SummaryIn this paper an inhibitor is described that is found in hemophilic plasma and serum different from any till now described inhibitor. The inhibitor only inhibits prothrombin activation in the “intrinsic clotting systems”. This inhibitor is probably not present in normal human plasma or serum. It is destroyed by ether and freeze drying, is labile to acid and storage at room temperature. It is stable upon dialysis and has not been adsorbed on barium sulfate, aluminum hydroxide or kaolin. It precipitates at 50% v/v saturation with alcohol. The nature of this inhibitor seems to be a protein or lipoprotein.Factor VIII was isolated from hemophilic plasma. The amount isolated was the same as from normal plasma and the activity properties were not different. Hemophiliacs have normal amounts of factor VIII.


1988 ◽  
Vol 167 (2) ◽  
pp. 421-439 ◽  
Author(s):  
B Pytowski ◽  
T G Easton ◽  
J E Valinsky ◽  
T Calderon ◽  
T Sun ◽  
...  

We have used mice selectively tolerized to antigens of human lymphocytes by treatment with cyclophosphamide to raise an mAb, BH2-C6, that reacts with a plasma membrane antigen specific for human neutrophils. This specificity is demonstrated by indirect immunofluorescence microscopy, cytochemical analysis of fluorescence-positive and -negative cell populations separated by flow cytometry, and by the selective, complement-mediated killing of mAb BH2-C6-treated neutrophils. Additional evidence for the neutrophil specificity of mAb BH2-C6 is shown by immunoelectron microscopy, which demonstrates a lack of reactivity with human eosinophils. Immunoblotting of SDS-PAGE-separated proteins of polymorphonuclear leukocytes with 125I-labeled BH2-C6 identifies protein with an average molecular mass of 157 kD. Binding studies show that, at saturation, neutrophils bind 214,000 molecules of 125I-BH2-C6 per cell. Addition of mAb BH2-C6 to neutrophils significantly reduces the number of C3bi-opsonized sheep erythrocytes (EIgMC3bi) bound by these cells. This reduction is partly reversed by the presence of soybean trypsin inhibitor (SBTI), indicating that at least one part of this inhibition is due to BH2-C6-stimulated secretion of a serine protease that may affect ligand binding. Cytochemical analysis of normal human bone marrow cells sorted by cytofluorimetry identifies the promyelocyte as the precursor cell that first expresses BH2-Ag on the plasma membrane. Using the leukemic cell line HL-60, we demonstrate that only inducers of granulocytic differentiation, cis-retinoic acid, and dimethyloxazolidine stimulate the expression of BH2-Ag. These results show that the expression of BH2-Ag during myelomonocytic differentiation is a property uniquely possessed by cells committed to the neutrophilic lineage.


2008 ◽  
Vol 14 (4) ◽  
pp. 357-361 ◽  
Author(s):  
Mohammad Ghazizadeh ◽  
Yoshihiro Sasaki ◽  
Tatsuo Oguro ◽  
Shigeru Sato ◽  
Seiko Egawa ◽  
...  

Observation of the internal ultrastructure of human chromosomes by transmission electron microscopy (TEM) has frequently been attempted in spite of the difficulties in detaching metaphase chromosome spreads from the glass slide for further processing. In this study we have used a method in which metaphase chromosome spreads were prepared on a flexible thermoplastic membrane (ACLAR) film. To assess chromosome identity, a diamidino-phenylindole staining and karyotying was first done using a conventional cytogenetic system. The chromosome spreads were then fixed with 1% osmium tetroxide, stained with freshly prepared 2% tannic acid, dehydrated, and flat-embedded in epoxy resin. The resin sheet was easily detachable and carried whole chromosome spreads. By this method, TEM observation of chromosomes from normal human lymphocytes allowed a thorough examination of the ultrastructure of centromeres, telomeres, fragile sites, and other chromosomal regions. Various ultrastructural patterns including thick electron dense boundaries, less dense internal regions, and extended chromatin loops at the periphery of the chromosomes were discernible. Application of the present method to chromosome research is expected to provide comprehensive information on the internal ultrastructure of different chromosomal regions in relation to function.


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