Isolabeling segments were found in the distal region of the long arm of Y chromosomes derived from human leukocytes grown through two replication cycles in medium containing BrdU and stained by the FPG technique. Three main types of Y chromosome staining patterns were demonstrated: I-Y chromosome with typical SCD, II-Y ...

Nucleolar organizer regions (NOR's) were demonstrated in metaphase chromosomes of the domestic rabbit. Oryctolagus cuniculus (L.) (New Zealand white strain) using silver staining. Sequential quinacrine banding and a modification of the Ag-AS silver precipitation technique with duplicate photography allowed identification of silver staining NOR's on the short arms of chromosomes ...

A simple and rapid technique is described whereby the nucleolus organizer regions (NORs) of human chromosomes can be differentially stained with silver. This staining is followed by trypsin-Giemsa banding on the same metaphase chromosomes. The metaphases simultaneously exhibit silver-stained NORs and G bands, allowing for the unequivocal identification of all ...

Chromosomes from a patient with a satellited Yq were stained with a silver procedure that differentially stains nucleolus organizer regions. The Yqs stained heavily in all cells examined, indicating the presence of ribosomal cistrons at this region. The Yqs also entered into satellite associations with the D and G group ...

The karyotype of two human meningiomas are reported in which, besides other aberrations, a deleted chromosome 1 and 6 could be observed. In these chromosomes most of the short arm is missing. After silver staining for the detection of NORs, not only the satellite regions of most of the acrocentric ...

Microspectrophotometric evaluation of differentially stained sister chromatids made it possible to analyse precisely the factors involved in the Giemsa methods. The concentration of Hoechst 33258, pH of the mounting medium temperature during UV-exposure and the quality (wavelength)of UV-light influenced the differential staining. Exposure of blacklight of 10(-5) M Hoechst 33528-stained ...

For a detailed study of chromosome morphology in meiotic prophase stages of Beta species, a special double staining technic has been developed. It consists of combined maceration-staining in an ethanol-hydrochloric acid-carmine mixture followed by poststaining of the squashed material in a diluted Giemsa solution. The technic yields well-spread prophase meiotic ...

Three persons with hereditary sclerosing poikiloderma were studied to find any clue to explain the mechanism involved in producing the cutaneous lesions which are so striking clinically and also evident histologically. Investigational studies included a blood chemistry screen, chromosome analyses, and skin biopsies evaluated by routine stains as well as ...

The inheritance of nucleolus organizer regions (NORs) was investigated by examining the degree of silver-staining in individual acrocentric chromosomes in two successive generations. The study was undertaken in six Down's syndrome children and their respective parents. Quinacrine fluorescent polymorphisms were used to identify individual acrocentrics and to determine which of ...

Differential staining of sister chromatids in BrdU-substituted human chromosomes is demonstrated by an ammoniacal silver carbonate procedure. With this method the chromosomes exhibit a subchromatid structure. Because proteolytic treatment indicated that the silver carbonate binds the chromosome proteins, changes of these components may be inferred in the BrdU-substituted chromosomes. Sister ...

The heterochromatin in mitotic cells of larval neural ganglia of Drosophila nasuta has been analysed by C-banding and by fluorescence studies. All chromosomes, except the 'dot'-like 4th chromosome pair, carry large blocks of heterochromatin which are darkly stained by C-banding, and which fluoresce uniformly brightly with Hoechst 33258, quinacrine mustard, ...

Acid hydrolysed DNA of rat liver was stained with Schiff's reagent at pHs 1.7 or 3.0 followed by staining with acriflavine-SO2 at pH 2.0 as well as with acriflavine-SO2 followed by Schiff's reagent at pH 1.7 or 3.0. Nuclei stained with Schiff's reagent at pH 1.7 were brown-yellow and an ...

When chromosomes of Allium cepa are subjected to a C-banding procedure (incubation in saturated barium hydroxide followed by phosphate buffer at 60 degrees C for 1 h) and then treated with Giemsa stain, bands appear at the telomeres of all chromosomes. Microspectrophotometric measurements of Feulgen-DNA content, demonstrated that the C-banding ...

Various reagents were tested for the purpose of developing an improved Giemsa staining technique for the differential staining of sister chromatids in human chromosomes. Reagents like acids, bases, buffers, protein denaturants and proteolytic enzymes were all potent inducers of differential staining. The best results were obtained by brief trypsinization followed ...

Three staining techniques (Giemsa, Q-banding and R-banding) are used consecutively to localize the breakage points in chromosomes of human lymphocytes, irradiated during G2-phase with gamma-rays, at doses ranging from 50 to 200 rad. The large majority, about 85% of the breaks, occurs at the interbands, between R- and Q-bands. The ...

The histologic appearances of tissues fixed by immersion and perfusion were compared, as well as the effects of these different fixatives: 10% neutral buffered formalin, Carnoy's fluid, and Bouin's fluid. Intravascular perfusion provided better tissue preservation than fixation by immersion. The quality of preservation by neutral buffered formalin was equal ...

Duplicate staining of human metaphase chromosomes, first with Giemsa followed by silver, revealed the presence of two small silver-stained bodies not seen in the Giemsa stained metaphases. Similar bodies were subsequently found in the metaphases of several animal groups. The size, structure, spatial relationships to the nucleus, behavior throughout the ...

Netropsin, an oligopeptide-type basic antibiotic, having exclusively A-T-specific DNA-binding affinity and situating itself into the minor groove of the double helix, represses the development of Q-bands if human chromosome preparations are treated with it before quinacrine mustard staining. The most probable interpretation of this effect is that netropsin interferes with ...

The fluorescence of Chironomus thummi giant chromosomes stained by acridine orange after mild acid hydrolysis (1N HCl at 37 degrees) has been studied. After very short hydrolysis as well as in control preparations (untreated by HCl) all chromosome regions show green fluorescence. After long hydrolysis (10 min) all chromosome bands ...

Procedures employing fluorescent dyes or Giemsa stain have been utilized to differentiate methaphase chromosomes into longitudinal segments termed bands. In spite of the immense practical utility of chromosome banding, the chemical basis of banding patterns remains incompletely understood. Physical chemical studies have elucidated the modes and specificities of the interaction ...

Chromosomes have been counted with the light microscope in fixed and stained preparations of Schizosaccharomyces pombe. The least ambiguous images were seen in zygotes fixed at meta-, ana- and telophase of meiosis II. They suggest that the haploid number of chromosomes in S. pombe is three.

Pre- and postmeiotic stages of male gametogenesis of 10 different vertebrate species belonging to mammals, birds, amphibians, and fishes were subjected to the Ag-AS staining technique (Goodpasture and Bloom, 1975). A uniform pattern of silver-staining is observable during spermatogenesis of the different vertebrate species. Silver-staining is present in spermatogonia and ...

Methaphase chromosomes from karyotypically normal adult humans (three males, six females) and one male with a 13p - chromosome were stained by quinacrine and then by the Ag-AS silver staining method to reveal nucleolus organizer regions (NORs). Each person had a characteristic number of Ag-stained chromosomes per cell, always fewer ...

The Ag-AS method, developed by Goodpasture and Bloom (1975) strains transcriptionally active nucleolus organizer regions (NORs) on the chromosomes and in the interphase nuclei. Metaphases and interphase nuclei of early mouse embryos (unfertilized eggs, pronucleus stages, 2-, 4-, 8-cell stages, and morulae) were subjected to silver-staining. First staining of a ...

Requirements for flow cytometry of metaphase chromosomes stained with three deoxyribonucleic acid (DNA)-specific fluorescent dyes--Hoechst 33258, Chromomycin A3, and ethidium bromide--are reviewed. Fluorescence properties of these three stains when bound to mitotic cells or to chromosomes in suspension are measured and compared with fluorescence properties when bound to DNA in ...

A new cytological procedure specifically suited to maize endosperms is presented. It uses 8-hydroxyquinoline with sucrose and aeration to pretreat the tissues. Glusulase is used to spread the cells. The procedure makes it possible to squash endosperms into a single cell layer and to photograph as many as 70 chromosomes ...

Different criteria for identifying the human Y chromosome using only conventional staining techniques were evaluated and a procedure based on three of them was developed. It leads to correct identification in 93% of cells even without resorting to differences in size between the Y and the other G chromosomes. The ...

Silver staining has been used to detect active nucleolus organizer regions (NOR's). By this criterion six mouse chromosomes, numbers 12, 15, 16, 17, 18 and 19, can have an NOR. The number and distribution of chromosomes with NOR's vary among inbred strains of Mus musculus musculus (C57BL/6J, BALB/cJ, C3H/HeJ and ...

The AT specificity of the fluorochromes DIPI and DAPI and the GC specificity of mithramycin are evidenced by observations in human, mouse, and bovine chromosomes. DIPI and DAPI produce a pattern similar to Hoechst 33258 in all three species, whereas mithramycin results in a reverse pattern. The AT-rich centromeric heterochromatin ...

DIPI and DAPI produce distinct fluorescent bands in human chromosomes similar to quinacrine banding patterns. Additionally, the AT rich secondary constrictions in the chromosomes Nos. 1, 9 and 16 are brightly fluorescent. On the other hand the brilliantly fluorescent regions after staining with quinacrine mustard in the chromosomes Nos. 3 ...

A hydrocortisone preparation containing methylparaben and propylparaben provoked bronchospasm and pruritus when given intravenously to an asthmatic patient, whereas another hydrocortisone preparation without paraben preservative did not. Direct and passive transfer (Prausnitz-Küstner) skin tests for immediate hypersensitivity to parabens were positive. Parabens, frequently employed as bacteriostatic agents, are capable of ...

The results obtained by acridine orange staining of chromosomes, after BrdU treatment, during one or two cell cycles, are described. The alterations of chromosome structure do not depend only on BrdU incorporation into DNA. Some other mechanisms are necessarily involved, and it is postulated that they are disturbances of protein-DNA ...

The optical absorption and fluorescence characteristics of 4'-6-diamidino-2-phenylindole (DAPI) with DNA and chromosomes were studied. There is a decrease in extinction coefficient and chift in the absorption spectra to a higher wavelength when the dye binds to DNA. The fluorescence of DAPI is enhanced by both A-T and G-C base-pairs. ...

Modified Giemsa procedures have been developed which elicit differential and highly selective staining of individual Y chromosomal lampbruch loops in spermatocyte nuclei of Drosophila hydei, D. NEOHYDEI, AND D. eohydei. In all three species the Y loop pair known as the "clubs" stains a brilliant dark red with Giemsa at ...

The nucleolar organizer-specific staining procedure, ammoniacal silver (Ag-AS), has been used to study the distribution and size of the nucleolar organizer regions (NORs) in chromosomes of the frog Rana blairi (Mecham, Littlejohn, Oldham, Brown and Brown). The somatic metaphase karyotype of this frog is similar to that of other frogs ...

Chromosomes suitable for karyotyping were produced from short-term cultures of cells from embryonic northern leopard frogs, Rana pipiens, at various growth stages. Embryos were minced in a trypsin solution. The tissue fragments were subsequently cultured in an electrolytic solution containing fetal calf serum and Colcemid. We found this technique to ...

Due to the very limited amount of knowledge available on the cytochemistry and architecture of fish chromosomes, an extensive banding study was carried out on chromosomes of the central mudminnow, Umbra limi. Through the use of fluorescent staining, C-banding, and silver staining, the chromosomes were characterized, and an idiogram was ...

Computerized chromosome analyses have resulted in up to 25% erroneous classifications, whereas a cytogenetically trained laboratory technician has an error rate of less than 0.1% in the preparation of a karyotype. In the project reported here, computerized classification is eliminated, and instead, the other steps of the analysis leading to ...

Silver nitrate has been used to demonstrate the chromosomal location of ribosomal cistrons in nine tissue-culture lines derived from human tumors of various pathological origins. Control individuals have a particular modal number (range 7--10) of D- and G-group chromosomes stained with silver. In the controls, 96.2% of the D- and ...

The nucleolus organizer regions of domestic sheep (Ovis aries), as shown by silver staining, are located terminally on chromosomes 1, 2, 3, 4, and 25. Significant differences between individuals in the number of Ag-NORs per cell were found. The frequency of involvement of individual chromosome pairs in nucleolar organization was ...

Metaphase chromosome preparations were made from leukocyte cultures of normal individuals. The cells were fixed in methanol:acetic acid (3:1 v/v), then dropped on cold, wet slides which were air-dried before storage at 4 degrees C. The slides were stained to identify the chromosomes by one of the following procedures: (1) ...

In this paper, model experiments on chicken red blood cell nuclei are described concerning the influence of methanol-acetic acid fixation and irradiation at different wavelengths, with and without prior Atebrin staining on subsequent Feulgen-stainability. In addition, data are reported on the influence on Feulgen-stainability of Giemsa-banding procedures, illumination of unstained ...

Unequivocal establishment of the correct diploid chromosome number in 1956 started the modern era of human cytogenetics. The next impetus came when the peripheral blood leukocyte culture technique for the chromosome preparation was described in 1960. Discovery of special staining procedures - banding techniques - in early seventies not only ...

Attention is directed towards the use of new techniques in cytogenetics. C-, G-, Q-, and R-banding methods are briefly discussed and illustrated. Methods of sister chromatid differential staining and silver staining for demonstration of nucleolus organizing regions are reviewed and their application in medical cytogenetics is pointed out. Frequency of ...

A combination of methods for fixation (sublimate, cobalt nitrate, formaldehyde, acetic acid in water), inclusion (celloidin dissolved in methyl salicylate, paraffin-paraplast) and staining was used to make serial sections easy, to avoid clefts and to give a good picture of segmentation mitoses, as well as a good contrast of yolk ...

A silver-staining technique specific for demonstrating nucleolus organizer regions (NOR) showed that the achromatic stalks of the 10 acrocentric autosomes of the human complement represent the NORs. Some variability in number of stained stalks is observed from cell-to-cell and from individual-to-individual. The silver-stained masses may extend beyond the stalks and ...

A reliable technique for staining human chromosomal nucleolar organizers (NOR's) with silver solutions is described. The NOR's can be selectively stained dark brown by silver solutions leaving the chromosome arms unstained and available for counterstaining with orcein or Giemsa dyes. Unequivocal identification of chromosome pairs bearing NOR's can be achieved ...

Stages of meiosis from the bluebell Endymion non-scriptus (L.) were studied by electron microscopy. The nucleolus went through the process of segregation at the beginning of meiosis with the movement to its surface of a pale-staining region. This region was shown to be the same as that called the 'L ...

Metaphase chromosomes of mouse strain L cells show strikingly uncondensed pericentric heterochromatic regions after treatment of living cells with the benzimidazol-derivative 33 258 Hoechst. In electron micrographs of total preparations after G-band staining the chromosomes are seen to be made up of irregularly folded fibrils of 200-400 A in diameter. ...

Human metaphase chromosomes were stained with silver following a pretreatment with a heated alkaline solution. The most conspicuous feature of the stained metaphases was the omission of silver staining in the secondary constrictions of chromosomes 1,9 and 16, and on the distal Yq. Our evidence indicates that the negative silver ...