Methods of transplanting nuclei from single cultured cells to unfertilized frogs' eggs

Development ◽  
1970 ◽  
Vol 24 (2) ◽  
pp. 249-255
Author(s):  
J. B. Gurdon ◽  
R. A. Laskey
Keyword(s):  
Xenopus Laevis ◽  
Phase Contrast ◽  
Cultured Cells ◽  
The Other ◽  
Phase Contrast Microscope ◽  
Cell Method ◽  
Attached Cell ◽  
Contrast Microscope

Two methods of transplanting single nuclei from monolayers of cultured cells to unfertilized eggs of Xenopus laevis are described, illustrated, and tested. The detached-cell method is simpler and quicker to operate and is suitable for homogeneous populations of cells which are easily removed from the substrate on which they are growing. The other, attached-cell, method is technically more elaborate, but is applicable to cells whose properties can be individually determined under the phase-contrast microscope and to cells which are not readily dissociated from other cells or from their substrate.

scholarly journals Blood Coagulation in Arthropods

Blood ◽  
1951 ◽  
Vol 6 (11) ◽  
pp. 1173-1198 ◽  
Author(s):  
CH. GRÉGOIRE
Keyword(s):  
Blood Coagulation ◽  
Blood Cells ◽  
Phase Contrast ◽  
Continuous Process ◽  
The Other ◽  
Present Material ◽  
Plasma Coagulation ◽  
Phase Contrast Microscope ◽  
Contrast Microscope ◽  
Special Category

Abstract 1. Thin films of freshly drawn hemolymph of about 360 insects belonging to 61 different species were observed under the phase contrast microscope and the process of coagulation investigated. Control of the observations by motion picture recordings were performed in a few species. 2. In the hemolymph of all the insects investigated, a category of hyaline hemocytes can easily be recognized under the phase contrast microscope from the other kinds of blood cells. Attempts of identification of these hyaline hemocytes with elements described in the classifications of insect blood cells based on fixation and staining were inconclusive. 3. In the insects in which the blood clotting does not occur, these hyaline hemocytes do not exhibit any important alteration. In species inn which blood coagulation occurs, the cells of this category appear to be highly labile to contact to glass surfaces. They undergo rapid modifications in their structure which play an important if not exclusive part in the initiation of the plasma coagulation. In the present material these alterations are of two kinds, each of them being related to a different appearance of the plasma reaction. They can occur alone or together. 4. In contrast to the hyaline hemocytes, the other categories of blood cells do not take part in the process of coagulation. Scattered or agglutinated at random, they are passively embedded in the coagulum. 5. In the present material, hemolymph coagulation appears to be a continuous process, initiated by alterations taking place in a single category of hemocytes. These alterations are followed by various degrees of plasma coagulation, from a general macroscopic clotting to a limited reaction detectable only under the microscope. 6. The results are at variance with former data in which the coagulation of insect blood was described as being either a cellular agglutination, in which no special part was recognized to be played by a special category of cells, or a plasma coagulation, both considered as two physiologically distinct processes, which can occur independently or together. On the other hand, the present results show an analogy with the type of coagulation described in crustacean blood by Hardy, Tait, Tait and Gunn, in which a special category of cells, Hardy's explosive cells, as distinguished from the other blood cells, has a specific and important part to play.

Histochemical and Morphological Studies of Lipids in the Oogenesis of Pheretima posthuma

1958 ◽  
Vol s3-99 (48) ◽  
pp. 475-484
Author(s):  
VISHWA NATH ◽  
BRIJ L. GUPTA ◽  
S. L. MANOCHA
Keyword(s):  
Phase Contrast ◽  
Chemical Change ◽  
Follicular Epithelium ◽  
Cholesteryl Esters ◽  
Lipid Bodies ◽  
Interference Microscope ◽  
Phase Contrast Microscope ◽  
Morphological Studies ◽  
Contrast Microscope ◽  
Second Category

A study of the oocytes of the earthworm, Pheretima posthuma, examined fresh under the phase-contrast and interference microscopes as well as by histochemical techniques, has revealed that there are two types of lipid bodies in the cytoplasm. The lipid bodies of the first type (L1) are smaller, appear as homogeneous, dark granules under the phase-contrast microscope, and have a protein-phospholipid core surrounded by a thick sheath of phospholipids only. The lipid bodies of the second category (L2), which arise as a result of growth and chemical change in L1 bodies, have a pure phospholipid core surrounded by a thick triglyceride sheath. They give a ringed appearance under the phase-contrast microscope. The study under the interference microscope shows that this ringed appearance is an optical artifact. The lipid spheres present in the follicular epithelium contain phospholipids only. The mitochondria are in the form of minute granules. They remain unchanged throughout oogenesis. Some vacuoles devoid of any lipids, proteins, or carbohydrates have been observed. They also remain unchanged. Pure triglyceride spheres, yolk globules, nucleolar extrusions, as well as cholesterols and cholesteryl esters are absent.

Redescription of Neelus fimbriatus Bretfeld & Trinklein, 2000 (Collembola: Neelidae) from Colombia

Zootaxa ◽  
2018 ◽  
Vol 4527 (3) ◽  
pp. 414
Author(s):  
ELIDA P. MARÍN ◽  
JOSÉ G. PALACIOS-VARGAS
Keyword(s):  
Phase Contrast ◽  
Phase Contrast Microscope ◽  
Contrast Microscope

Neelus fimbriatus is redescribed using specimens from Colombia. Drawings and phase contrast microscope photos of the species are used. New characters are used as tibiotarsal tuberculate setae and abdominal ventral acetabula. 

scholarly journals Evaluation of Haematuria and Use of Phase Contrast Microscope: A Short Review

1970 ◽  
Vol 20 (1) ◽  
pp. 63-67 ◽  
Author(s):  
T Sultana ◽  
T Sultana ◽  
MQ Rahman ◽  
ANN Ahmed
Keyword(s):  
Phase Contrast ◽  
Diagnostic Marker ◽  
Short Review ◽  
Red Cells ◽  
Phase Contrast Microscopy ◽  
Red Cell ◽  
Phase Contrast Microscope ◽  
Non Invasive ◽  
Contrast Microscope ◽  
Contrast Microscopy

For centuries physicians have been using urine as one of the non-invasive means for assessing diseases. Haematuria is a frequently encountered abnormality in clinical practice. Haematuria may have either a glomerular or a non-glomerular origin. The morphological study of urinary red cells by Phase-Contrast Microscopy (PCM) is a useful diagnostic marker for glomerular bleeding, if correctly interpreted and used. Today, urinalysis and in particular identification of red cells morphology by Phase-Contrast Microscopy has been a widely accepted technique for determining the site of haematuria. A short review on haematuria and Phase-Contrast Microscopy are presented here for updating knowledge and academic interest. Key words: Phase-contrast microscope; Haematuria; Dysmorphic red cell. DOI: http://dx.doi.org/10.3329/jdmc.v20i1.8584 J Dhaka Med Coll. 2011; 20(1) :63-67

scholarly journals Qualities of goat semen in Tris-Citrate-Glucose extender containing glutathione

1970 ◽  
Vol 27 (2) ◽  
pp. 46-55 ◽  
Author(s):  
B Mishra ◽  
MGS Alam ◽  
MAMY Khandokar ◽  
S Mazumder ◽  
MN Munsi
Keyword(s):  
Sperm Motility ◽  
Artificial Insemination ◽  
Phase Contrast ◽  
Phase Contrast Microscope ◽  
Contrast Microscope ◽  
And Control ◽  
Control Samples

Glutathione (GSH) 0 (control), 2, 4 and 8 mM was used in the preservation of chilled goat semen. Treated and control samples were kept at 4 – 5°C up to seven days. Sperm motility and acrosome abnormality were assessed daily under phase contrast microscope. The sperm motility was significantly (P<0.01) higher in the semen treated with 8 mM GSH. Optimum sperm motility (≥50%) for artificial insemination was retained for three days with 2 and 4 mM GSH and up to four days with 8 mM GSH. Acrosomal damage was significantly (P<0.01) reduced to ≤ 1.0% after addition of 8 mM GSH. It is suggested that GSH may be used as an antioxidant for better preservation of goat semen for artificial insemination. DOI: 10.3329/bvet.v27i2.7554 Bangl. vet. 2010. Vol. 27, No. 2, 46 – 55

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