QUINACRINE FLUORESCENCE AND Q-BANDING PATTERNS OF HUMAN CHROMOSOMES.: I. Effects of Varying Factors

1975 ◽  
Vol 17 (1) ◽  
pp. 81-92 ◽  
Author(s):  
C. C. Lin ◽  
H. van de Sande ◽  
W. K. Smink ◽  
D. R. Newton
Keyword(s):  
Exposure Time ◽  
Uv Light ◽  
Human Chromosomes ◽  
Concave Mirror ◽  
Banding Patterns ◽  
Fluorescent Microscope ◽  
Sperm Dna ◽  
Quinacrine Fluorescence ◽  
Well Differentiated ◽  
Salmon Sperm Dna

Various factors involved in the production of "Q-bands" have been studied. It was found that a Zeiss standard WL fluorescent microscope required a shorter exposure time for photography as compared to a Zeiss photomicroscope. The minimal exposure time was obtained when the standard WL microscope was equipped with a UV light source containing a DC powered mercury burner and a concave mirror. Further, the pH and type of water used in the staining, washing and mounting of the slide were also important factors in producing clear and well differentiated "Q-bands". It also appears that the factors involved in the production of "Q-bands" effect the enhancement or quenching of fluorescence by poly d(A-T).poly d(A-T) and salmon sperm DNA or poly dG∙poly dC respectively. This preliminary report also suggests that DNA or polynucleotides with a specific base sequence may play an important role in Q-banding patterns on chromosomes.

Chromosome Analysis of Two Related Heteroploid Mouse Cell Lines by Quinacrine Fluorescence

1973 ◽  
Vol 12 (1) ◽  
pp. 263-274
Author(s):  
P. W. ALLDERDICE ◽  
O. J. MILLER ◽  
D. A. MILLER ◽  
D. WARBURTON ◽  
P. L. PEARSON ◽  
...  
Keyword(s):  
Cell Lines ◽  
Chromosome Analysis ◽  
Mouse Cell ◽  
Previous Method ◽  
Structural Rearrangements ◽  
Metaphase Chromosomes ◽  
Detailed Characterization ◽  
Banding Patterns ◽  
Fluorescent Banding ◽  
Quinacrine Fluorescence

The fluorescent banding patterns of quinacrine-stained metaphase chromosomes have been studied in 2 related mouse cell lines, A9 and a malignant derivative of A9, A9HT. In both cell lines virtually every chromosome has a distinctive banding pattern which permits its recognition. More than three quarters of the chromosomes have structural rearrangements, but the origin of nearly two thirds of the chromosomes could be determined by their banding patterns. The quinacrine fluorescence technique permits far more detailed characterization and comparison of heteroploid cell lines than any previous method. A9 and A9HT are karyologically quite similar, with many of the same marker chromosomes. There are, however, characteristic differences. A9HT, although it has a smaller average number of chromosomes per cell, appears to be more heterogeneous.

Spatial relations of human chromosomes identified by quinacrine fluorescence at metaphase

1973 ◽  
Vol 18 (4) ◽  
pp. 297-306 ◽  
Author(s):  
D. Warburton ◽  
A. F. Naylor ◽  
F. E. Warburton
Keyword(s):  
Spatial Relations ◽  
Human Chromosomes ◽  
Quinacrine Fluorescence

G-banding patterns of high-resolution human chromosomes 6?22, X, and Y

1979 ◽  
Vol 49 (3) ◽  
pp. 291-306 ◽  
Author(s):  
J. J. Yunis ◽  
D. W. Ball ◽  
J. R. Sawyer
Keyword(s):  
High Resolution ◽  
Human Chromosomes ◽  
Banding Patterns

scholarly journals Role of Extracellular DNA during Biofilm Formation by Listeria monocytogenes

2010 ◽  
Vol 76 (7) ◽  
pp. 2271-2279 ◽  
Author(s):  
Morten Harmsen ◽  
Martin Lappann ◽  
Susanne Kn�chel ◽  
S�ren Molin
Keyword(s):  
Listeria Monocytogenes ◽  
Biofilm Formation ◽  
Extracellular Dna ◽  
Central Component ◽  
High Molecular Weight Dna ◽  
Food Borne ◽  
Attachment Sites ◽  
Sperm Dna ◽  
Salmon Sperm Dna

ABSTRACT Listeria monocytogenes is a food-borne pathogen that is capable of living in harsh environments. It is believed to do this by forming biofilms, which are surface-associated multicellular structures encased in a self-produced matrix. In this paper we show that in L. monocytogenes extracellular DNA (eDNA) may be the only central component of the biofilm matrix and that it is necessary for both initial attachment and early biofilm formation for 41 L. monocytogenes strains that were tested. DNase I treatment resulted in dispersal of biofilms, not only in microtiter tray assays but also in flow cell biofilm assays. However, it was also demonstrated that in a culture without eDNA, neither Listeria genomic DNA nor salmon sperm DNA by itself could restore the capacity to adhere. A search for additional necessary components revealed that peptidoglycan (PG), specifically N-acetylglucosamine (NAG), interacted with the DNA in a manner which restored adhesion. If a short DNA fragment (less than approximately 500 bp long) was added to an eDNA-free culture prior to addition of genomic or salmon sperm DNA, adhesion was prevented, indicating that high-molecular-weight DNA is required for adhesion and that the number of attachment sites on the cell surface can be saturated.

Oligodeoxyribonucleotides derived from salmon sperm DNA: An alternative to defibrotide

Biologicals ◽  
2013 ◽  
Vol 41 (3) ◽  
pp. 190-196
Author(s):  
Chang-Ye Hui ◽  
Yan Guo ◽  
Xi Zhang ◽  
Jian-Hua Shao ◽  
Xue-Qin Yang ◽  
...  
Keyword(s):  
Sperm Dna ◽  
Salmon Sperm Dna

Degradation of PVDF-based composite membrane and its impacts on membrane intrinsic and separation properties

2016 ◽  
Vol 36 (3) ◽  
pp. 261-268 ◽  
Author(s):  
Mei Jiun Lee ◽  
Chi Siang Ong ◽  
Woei Jye Lau ◽  
Be Cheer Ng ◽  
Ahmad Fauzi Ismail ◽  
...  
Keyword(s):  
Uv Irradiation ◽  
Exposure Time ◽  
Composite Membrane ◽  
Polyvinylidene Fluoride ◽  
Uv Light ◽  
Irradiation Time ◽  
Uv Exposure ◽  
Polymeric Membrane ◽  
Permeate Flux ◽  
Wastewater Treatment Process

Abstract In this work, an attempt was made to evaluate the effects of ultraviolet (UV) irradiation period on the intrinsic and separation properties of composite membrane composed of organic polyvinylidene fluoride and inorganic titanium dioxide (TiO2) nanoparticles by exposing the membrane to UV-A light for up to 250 h. The changes on membrane structural morphologies and chemical characteristics upon UV exposure were studied by field-emission scanning electron microscope and Fourier transform infrared, respectively. It was observed that some cracks and fractures were formed on the membrane outer surface when it was exposed to 120-h UV light. Further increase in UV irradiation time to 250 h had caused membrane structure to collapse, turning it into powder form. Filtration experiments showed that the permeate flux of irradiated membrane was significantly increased from 10.89 L/m2 h to 21.84 L/m2 h (>100% flux increment) while oil rejection decreased with increasing UV exposure time from 0 h to 120 h. Furthermore, the mechanical strength and thermal stability of irradiated membrane were also reported to decrease with increasing UV exposure time, suggesting the negative impacts of UV light on the membrane overall stability. This research is of particular importance to evaluate the suitability and sustainability of polymeric membrane, which is widely considered as the host for photocatalyts and used for wastewater treatment process under UV irradiation.

Development of UV Distribution Model for the Non-Contact Type UV Disinfection System

2011 ◽  
Vol 9 (1) ◽  
Author(s):  
Sung Hong Kim ◽  
Young Gyun Choi ◽  
Dooil Kim
Keyword(s):  
Mathematical Model ◽  
Exposure Time ◽  
Uv Light ◽  
Treatment Plant ◽  
Water Layer ◽  
Distribution Model ◽  
Uv Disinfection ◽  
Contact Type ◽  
Irradiation System ◽  
Uv Lamp

Fouling on the quartz sleeve reduces the transmittance of UV light through the sleeve into the water in submerged UV disinfection system. The concept of a non-contact type of UV disinfection system was introduced in this study. UV lamps and their quartz sleeves hang over the water surface and there is no interface between the sleeve and water. Indeed, there is no fouling. Based on optical laws and UV distribution model, a detailed mathematical model for a non-contact type UV disinfection system was developed and simulated in this study. UV light passes through 4 media of air-quartz-air and water in case of non-contact type irradiation system. By the simulation of the mathematical model of the system, it is known that the non-contact type of UV system requires 2.5 times more powerful UV lamp or a lamp with longer exposure time than that of the submerged type of UV system. In a non-contact type of UV system, high-reflective ceiling material can increase the UV intensity of the water layer as much as 28 percent more than the case of non-reflective ceiling material. The non-contact type UV irradiation system requires more powerful lamp or one that have longer exposure time. Nevertheless, considering the fouling attenuation and maintenance problem associated with the fouling, non-contact type of UV disinfection system deserves to be practically considered, especially in a small to middle scale water or wastewater treatment plant.

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