A direct technique for the preparation of chromosomes from early equine embryos

1985 ◽  
Vol 27 (3) ◽  
pp. 365-369 ◽  
Author(s):  
April Romagnano ◽  
W. Allan King ◽  
Claude-Lise Richer ◽  
Marie-Antoinette Perrone
Keyword(s):  
Cell Loss ◽  
Giemsa Staining ◽  
C Banding ◽  
Direct Technique

A technique is described for the preparation of banded chromosomes from early equine embryos cultured for less than 10 h in a medium containing bromodeoxyuridine. In addition to standard Giemsa staining and C-banding, chromosomes thus prepared can also be R-banded by either the RBA or the RB-FPG methods. This technique is rapid, repeatable, and limits cell loss, making it ideal for the preparation of early embryos.Key words: embryos, chromosomes, banding, horse, cow.

G and/or C-bands in plant chromosomes?

1984 ◽  
Vol 71 (1) ◽  
pp. 111-120
Author(s):  
I. Schubert ◽  
R. Rieger ◽  
P. Dobel
Keyword(s):  
Constitutive Heterochromatin ◽  
Giemsa Staining ◽  
Giemsa Banding ◽  
Base Pairs ◽  
Banding Patterns ◽  
C Banding ◽  
Plant Chromosomes ◽  
Nucleolus Organizing Region ◽  
Similarities And Differences ◽  
Simple Sequence

Similarities and differences become evident from comparisons of centromeric and non-centromeric banding patterns in plant and animal chromosomes. Similar to C and G-banding in animals (at least most of the reptiles, birds and mammals), centromeric and nucleolus-organizing region bands as well as interstitially and/or terminally located non-centromeric bands may occur in plants, depending on the kind and strength of pretreatment procedures. The last group of bands may sometimes be subdivided into broad regularly occurring ‘marker’ bands and thinner bands of more variable appearance. Non-centromeric bands in plants often correspond to blocks of constitutive heterochromatin that are rich in simple sequence DNA and sometimes show polymorphism; they thus resemble C-bands. However, most of these bands contain late-replicating DNA. Also they are sometimes rich A X T base-pairs, closely adjacent to each other and positionally identical to Feulgen+ and Q+ bands, thus being comparable to mammalian G-bands. Although banding that is reverse to the non-centromeric bands after Giemsa staining is still uncertain in plants, reverse banding patterns can be obtained with Feulgen or with pairs of A X T versus G X C-specific fluorochromes. It is therefore concluded that not all of the plant Giemsa banding patterns correspond to C-banding of mammalian chromosomes. Before the degree of homology between different Giemsa banding patterns in plants and G and/or C-bands in mammals is finally elucidated, the use of the neutral term ‘Giemsa band’, specified by position (e.g. centromeric, proximal, interstitial, terminal), is suggested to avoid confusion.

Differential Giemsa staining in plants IV. C-Banding in Avena strigosa

1976 ◽  
Vol 67 (2) ◽  
pp. 117-118 ◽  
Author(s):  
SHENG-TIAN YEN ◽  
W. GARY FILION
Keyword(s):  
Giemsa Staining ◽  
C Banding ◽  
Avena Strigosa

scholarly journals Analysis of the karyotype of Callisia elegans Alexand. (Commelinaceae) including differential staining of chromosomes

2014 ◽  
Vol 57 (3) ◽  
pp. 317-327
Author(s):  
Elżbieta Weryszko-Chmielewska
Keyword(s):  
Giemsa Staining ◽  
Differential Staining ◽  
Interphase Nuclei ◽  
Unequal Size ◽  
C Banding ◽  
Nucleolar Organizers

The number and morphology of <em>Callisia elegans</em> Alexand. chromosomes were studied employing staining with acetic carmine and differential Giemsa staining. It was found that its karyotype was 2n = 12 chromosomes, whose lengths fell in the range of 16.8 to 8.8 µm. The chomosomes, arranged in order of length, were classified respectively to types: sm, t, t, t, t, st. The distribution of C-banding is given for this karyotype. The presence of microsatellites on the long and short arms was found in the chromosomes of the second pair. Frequently there were 4 nucleoli of unequal size in interphase nuclei. In many cells, lower numbers of nucleoli (3-1) were seen which was -probably due to their fusion. The maximum number of nucleoli corresponded to the number of nucleolar organizers accompanying the satellites.

POLYMORPHISM IN THE GIEMSA C-BANDING PATTERN OF RYE CHROMOSOMES

1978 ◽  
Vol 20 (3) ◽  
pp. 307-312 ◽  
Author(s):  
T. Lelley ◽  
K. Josifek ◽  
P. J. Kaltsikes
Keyword(s):  
Secale Cereale ◽  
Banding Pattern ◽  
Inbred Lines ◽  
Giemsa Staining ◽  
C Banding ◽  
Secale Cereale L

Extensive polymorphism was found with regard to the presence and size of Giemsa-staining bands in the chromosomes of six inbred lines of cultivated rye (Secale cereale L.). The amount of polymorphism differed from chromosome to chromosome, with 6R being the most variable and 3R or 7R the least.

DIFFERENTIAL GIEMSA STAINING IN PLANTS. VI. CENTROMERIC BANDING

1979 ◽  
Vol 21 (3) ◽  
pp. 373-378 ◽  
Author(s):  
W. Gary Filion ◽  
David H. Blakey
Keyword(s):  
Room Temperature ◽  
Chromosome Banding ◽  
Giemsa Staining ◽  
Barium Hydroxide ◽  
Banding Technique ◽  
Giemsa Banding ◽  
Metaphase Chromosomes ◽  
Somatic Metaphase ◽  
C Banding ◽  
Hydrolysis Temperature

Somatic metaphase chromosomes of Tulipa which were subjected to various hydrolyses with several times and temperatures displayed two distinctive types of C-banding when stained using the BSG (Barium hydroxide/Saline/Giemsa) chromosome banding technique. In addition to the two types of Giemsa bands, namely intercalary/terminal and centromeric, a unique transition from the former to the latter type of banding was observed. That is, at the point of transition from intercalary/terminal to centromeric banding, both types were present at one time. The two types of Giemsa banding resulted from different HCl hydrolysis times and temperatures; centromeric bands being observed after either a prolonged hydrolysis at room temperature or an increase in the hydrolysis temperature to 60 °C. These results are discussed in relation to the mechanisms of chromosome banding.

scholarly journals Cytogenetic studies of two freshwater sciaenids of the genus Plagioscion (Perciformes, Sciaenidae) from the central Amazon

1999 ◽  
Vol 22 (3) ◽  
pp. 351-356 ◽  
Author(s):  
Eliana Feldberg ◽  
Jorge Ivan Rebelo Porto ◽  
Elen Bethlen Pedraça dos Santos ◽  
Francisco Carlos Souza Valentim
Keyword(s):  
Chromosome Pair ◽  
Giemsa Staining ◽  
Central Amazon ◽  
C Banding ◽  
Cytogenetic Studies ◽  
Cytogenetic Characterization ◽  
Almost All ◽  
First Time

Cytogenetic characterization of two freshwater sciaenid species from the genus Plagioscion (P. squamosissimus and Plagioscion sp.) was obtained for the first time. Giemsa staining, Ag-NOR and C-banding revealed that both species presented 2n = 48 chromosomes (almost all acrocentric). Single NORs and heterochromatin were found mainly at the pericentromeric position. Karyotypic formulae and NOR location proved to be valuable in showing both interspecific and intraspecific differences. All chromosomes were acrocentric in P. squamosissimus. NORs were located at proximal positions on the long arms of the last chromosome pair of the complement, and were heteromorphic due to size differences. Such heteromorphic NORs seem to be associated with each population sampled. Plagioscion sp. presented two cytotypes: cytotype a (2M + 46A) and cytotype b (48A). In both cytotypes, NOR-bearing chromosomes were located at the proximal position on the long arms of the first chromosome pair of the complement. However, NOR-bearing chromosomes were metacentric in cytotype a and acrocentric in cytotype b.

Role of the Small (40S) Subunits in the Structure of the Interface of Eukaryotic Ribosomes

1980 ◽  
Vol 38 ◽  
pp. 548-549
Author(s):  
M. Boublik ◽  
N. Robakis ◽  
W. Hellmann ◽  
F. Jenkins
Keyword(s):  
Structural Similarity ◽  
High Resolution Electron Microscopy ◽  
Peptide Bond ◽  
Uranyl Acetate ◽  
Mutual Orientation ◽  
Mutual Position ◽  
Peptide Bond Formation ◽  
Resolution Electron ◽  
Direct Technique ◽  
Structural Details

Ribosomes are ribonucleoprotein particles which process the genetic information coded in mRNA into protein synthesis. The analogy in function and composition of ribosomes from various sources, both prokaryotic and eukaryo-tic, imply a structural similarity. At present, high resolution electron microscopy is the most direct technique with a potential to resolve the extent of the structural homology of ribosomal particles at a macromolecular level. The structure of ribosomes is highly complex as a result of the large number of their constituents. In general, 80S eukaryotic monosomes consist of two uneven subunits - large (60S) and small (40S) - accomodating four different RNAs and approximately 80 different proteins. Mutual orientation of both subunits on the monosome is of particular interest because it determines the interface, the supposed site of interactions of ribosomes with other macro-molecules involved in peptide bond formation. Since entrapping of the contrasting solution (0.5% aqueous uranyl acetate) obscures all structural details in the interface, information on its architecture is limited to an indirect reconstruction based on the established 3-D structure of both sub-units and their mutual position after association.

Strahlenwirkung am Normalgewebe

2010 ◽  
Vol 49 (S 01) ◽  
pp. S53-S58 ◽  
Author(s):  
W. Dörr
Keyword(s):  
Radiation Exposure ◽  
Normal Tissue ◽  
Radiation Effects ◽  
A Priori ◽  
Cell Loss ◽  
Turnover Time ◽  
Complete Healing ◽  
Internal Radiotherapy ◽  
Normal Tissues ◽  
Chronic Radiation

SummaryThe curative effectivity of external or internal radiotherapy necessitates exposure of normal tissues with significant radiation doses, and hence must be associated with an accepted rate of side effects. These complications can not a priori be considered as an indication of a too aggressive therapy. Based on the time of first diagnosis, early (acute) and late (chronic) radiation sequelae in normal tissues can be distinguished. Early reactions per definition occur within 90 days after onset of the radiation exposure. They are based on impairment of cell production in turnover tissues, which in face of ongoing cell loss results in hypoplasia and eventually a complete loss of functional cells. The latent time is largely independent of dose and is defined by tissue biology (turnover time). Usually, complete healing of early reactions is observed. Late radiation effects can occur after symptom-free latent times of months to many years, with an inverse dependence of latency on dose. Late normal tissue changes are progressive and usually irreversible. They are based on a complex interaction of damage to various cell populations (organ parenchyma, connective tissue, capillaries), with a contribution from macrophages. Late effects are sensitive for a reduction in dose rate (recovery effects).A number of biologically based strategies for protection of normal tissues or for amelioration of radiation effects was and still is tested in experimental systems, yet, only a small fraction of these approaches has so far been introduced into clinical studies. One advantage of most of the methods is that they may be effective even if the treatment starts way after the end of radiation exposure. For a clinical exploitation, hence, the availability of early indicators for the progression of subclinical damage in the individual patient would be desirable. Moreover, there is need to further investigate the molecular pathogenesis of normal tissue effects in more detail, in order to optimise biology based preventive strategies, as well as to identify the precise mechanisms of already tested approaches (e. g. stem cells).

The identification of diabetes genes mediating β-cell loss and hyperglycemia using positional cloning

2018 ◽  
Author(s):  
TT Cui ◽  
N Hallahan ◽  
W Jonas ◽  
P Gottmann ◽  
M Jähnert ◽  
...  
Keyword(s):  
Positional Cloning ◽  
Cell Loss ◽  
Β Cell

Leucocytes and Thrombosis

1973 ◽  
Vol 30 (01) ◽  
pp. 036-046 ◽  
Author(s):  
D.C Banks ◽  
J.R.A Mitchell
Keyword(s):  
Cell Count ◽  
White Cell Count ◽  
Cell Loss ◽  
White Cell ◽  
Structural Resemblance ◽  
The Masses

SummaryWhen heparinised blood is rotated in a glass flask at 37°C. the white cell count falls and it has been shown that this is due to the adherence and aggregation of polymorphonuclear white cells on the wall of the flask. The masses formed bear a close structural resemblance to thrombi and the mechanisms involved in white cell loss during rotation may therefore increase our knowledge of the thrombotic process.

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