Sperm Penetration of the Zona Pellucida of the Pig Egg

1964 ◽  
Vol 41 (3) ◽  
pp. 603-608
Author(s):  
Z. DICKMANN ◽  
P. J. DZIUK
Keyword(s):  
Zona Pellucida ◽  
Phase Contrast ◽  
Sperm Head ◽  
Narrow Slit ◽  
Penetration Curve ◽  
Phase Contrast Microscope ◽  
Sequence Of Events ◽  
Contrast Microscope ◽  
Sperm Penetration

1. Pig eggs were examined with the ordinary and phase-contrast microscope in search for clues about the process of sperm penetration of the zona pellucida. 2. The following observations were made, (i) The zona pellucida consists of three concentric layers--the inner-zona, the middle-zona, and the outer-zona. (ii) The fertilizing spermatozoon makes a narrow slit in the zona by penetrating through it. The slit has a particular shape referred to as ‘the penetration curve’. (iii) Extra spermatozoa (i.e. spermatozoa other than the fertilizing spermatozoon) enter the zona and follow a course very similar to that of the fertilizing spermatozoon, but they can penetrate it only as far as the middle-zona. Extra spermatozoa have not been observed in the inner-zona, indicating that in this layer the ‘zona reaction’ is normally absolute, (iv) A filament extending from the apex of the sperm head has been observed in spermatozoa embedded in the zona. It is suggested that the sperm path through the zona is determined by this filament, which is therefore termed the sperm-penetration filament (SPF). 3. On the basis of these observations the following sequence of events in the passage of a spermatozoon through the zona is suggested. First, the spermatozoon attaches to the zona; it then ejects into the zona the SPF. The SPF, in turn, guides the spermatozoon on its curved course through the zona.

Establishment of a practical sperm penetration test for bovine semen

2013 ◽  
Vol 41 (05) ◽  
pp. 297-303
Author(s):  
A. C. Becher ◽  
K. Failing ◽  
J. Kauffold ◽  
A. Wehrend
Keyword(s):  
Phase Contrast ◽  
Polyacrylamide Gel ◽  
Technical Equipment ◽  
Penetration Test ◽  
Capillary Tubes ◽  
Bovine Semen ◽  
Penetration Distance ◽  
Phase Contrast Microscope ◽  
Contrast Microscope ◽  
Sperm Penetration

Summary Objective: Several methods for evaluating semen quality have been developed in addition to traditional semen analysis. Most of these methods are very complex and require expensive technical equipment as well as special knowledge to be performed. The aim of this study was to establish an easy and cost-effective sperm penetration test for bovine semen using artificial media. Additionally a standard procedure for test performance should be figured out. Material and methods: In the first part of the study four different capillary tubes or pipettes were evaluated in order to determine the most appropriate one to use in the penetration test. In the second part of the study the tubes were filled with different compositions of polyacrylamide gel and subsequently incubated at 37.5 °C for 30 minutes. Sperm penetration was then evaluated using a phase contrast microscope, measuring the penetration distance of the first, the first motile and the five vanguard motile spermatozoa as well as determining the number of sperm cells cumulated per low power field (LPF) at three distinct distances in the tube. Results: Non-heparinised haematocrit capillary tubes were the most appropriate tubes for performance of sperm penetration test as 100% of used capillaries were evaluable after incubation and size of the capillaries allowed a simple handling and good visualisation of migrated spermatozoa. Best results were achieved with 1.9% polyacrylamide gel containing phosphate-buffered saline. Measuring the penetration distance of the vanguard motile sperm cell can be recommended for test evaluation. Conclusion: A sperm penetration test with 1.9% polyacrylamide using non-heparinised capillary tubes was established. Results showed high reproducibility, the procedure is simple to carry out and only requires a phase contrast microscope.

The Passage of Spermatozoa Through and into the Zona Pellucida of the Rabbit Ecg

1964 ◽  
Vol 41 (1) ◽  
pp. 177-182
Author(s):  
Z. DICKMANN
Keyword(s):  
Zona Pellucida ◽  
Phase Contrast ◽  
Narrow Slit ◽  
Phase Contrast Microscopy ◽  
Penetration Curve ◽  
Characteristic Shape ◽  
Contrast Microscopy ◽  
Pass Through

To obtain information about the sperm pathway through the zona pellucida of the rabbit egg, ordinary and phase contrast microscopy were used to study (1) zonae through which spermatozoa had passed, and (2) spermatozoa within zonae. The observations revealed that the spermatozoon makes a narrow slit in the zona as it passes through it. Such slits have a characteristic shape--‘the penetration curve’. It is concluded that to pass through the zona, the spermatozoon must follow the penetration curve. Most of the spermatozoa observed within the thickness of the zona apparently started on the curved course and then stopped. They may have stopped within the zona because they were deficient in a substance which normally acts in conditioning the zona to allow spermatozoa to pass through it. Hair-like structures protrude from the front ends of sperm heads into the zona. No definite conclusion has been reached as to whether they are slits in the zona or solid structures; however, the pictorial evidence favours the interpretation that they are filaments protruding from the sperm heads.

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. 

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 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

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