scholarly journals ​Spermatozoa Sorting Techniques for the Sex Pre-selection: A Review

2021 ◽  
Author(s):  
S.J. Naidu ◽  
A. Arangasamy ◽  
S. Selvaraju ◽  
B.K. Binsila ◽  
J.P. Ravindra ◽  
...  
Keyword(s):  
Economic Growth ◽  
Flow Cytometry ◽  
Gradient Centrifugation ◽  
Percoll Gradient ◽  
Potential Significance ◽  
Cell Sorter ◽  
Farm Productivity ◽  
Marker Proteins ◽  
Alternative Approach ◽  
Specific Membrane

Furtherance of sex pre-selection techniques is extremely beneficial for the farm productivity and economic growth of the country. Several techniques such as flow cytometry, swim-up, percoll gradient centrifugation, lumisort and immunogenic spermatozoa sexing developed so far are reviewed with their principles, advantages, disadvantages and possible ways for developing a highly reliable and efficient technique to achieve success in obtaining offspring of the desired sex. Out of all these techniques available till now, sorting X- and Y- spermatozoa using fluorescence-activated cell sorter (FACS) is the most successful and commercially available technique, which employs sorting of spermatozoa based on DNA content. Despite its effectiveness, there are disadvantages concerning cost, sperm damage, trained technical person, low conception rate, etc. An alternative approach that might have potential significance could be the identification of sex-specific membrane marker proteins for the immunological method of spermatozoa sorting.

PAICA: A Method for Characterizing Platelet-Associated Antibodies - Its Application to the Study of Idiopathic Thrombocytopenic Purpura and to the Detection of Platelet-bound c7E3

1996 ◽  
Vol 76 (06) ◽  
pp. 1020-1029 ◽  
Author(s):  
Laurent Macchi ◽  
Gisèle Clofent-Sanchez ◽  
Gérald Marit ◽  
Claude Bihour ◽  
Catherine Durrieu-Jais ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Flow Cytometry ◽  
Idiopathic Thrombocytopenic Purpura ◽  
Antithrombotic Therapy ◽  
Membrane Glycoproteins ◽  
Serum Antibodies ◽  
Platelet Destruction ◽  
Thrombocytopenic Purpura ◽  
Capture Assay ◽  
Specific Membrane

SummaryIn idiopathic thrombocytopenic purpura (ITP), autoantibodies reacting with antigens on the platelet membrane bring about accelerated platelet destruction. We now report PAICA (“Platelet-Associated IgG Characterization Assay”), a method for detecting autoantibodies bound to specific membrane glycoproteins in total platelet lysates. This monoclonal antibody (MAb) capture assay takes into account the fact that antibodies on circulating platelets may be translocated to internal pools as well as being on the surface. A total of twenty ITP patients were examined by PAICA, and the results compared with those obtained by measuring (i) serum antibodies bound to paraformaldehyde-fixed control platelets by ELISA, (ii) IgG bound to the surface of the patient’s own platelets by flow cytometry (PSIgG), (iii) total platelet-associated IgG (PAIgG) by ELISA and (iv) serum antibodies reacting with control platelets by MAIPA (“Monoclonal Antibody-specific Immobilization of Platelet Antigens”). Of twelve patients with elevated PAIgG, nine had increased PSIgG yet eleven reacted positively in PAICA. Of these, eight possessed antibodies directed against GP Ilb-IIIa, two against GP Ib-IX and one patient possessed antibodies directed against GP Ilb-IIIa and GP Ia-IIa respectively. Only seven of the patients possessed serum antibodies detectable by MAIPA. PAICA was also able to detect platelet-associated c7E3 (the chimeric form of Fab fragments of the MAb 7E3) following its infusion during antithrombotic therapy, when it proved more sensitive over a seven-day period than a MAIPA assay adapted for assessing surface-bound antibody. We propose that PAICA provides added sensitivity to the detection of platelet-associated antibodies in immune thrombocytopenias or following therapy with humanized MAbs.

scholarly journals Isolation and characterization of two distinct low-density, Triton-insoluble, complexes from porcine lung membranes

1996 ◽  
Vol 319 (3) ◽  
pp. 887-896 ◽  
Author(s):  
Edward T PARKIN ◽  
Anthony J TURNER ◽  
Nigel M HOOPER
Keyword(s):  
Light Scattering ◽  
Gradient Centrifugation ◽  
Buoyant Density ◽  
Annexin V ◽  
Density Fraction ◽  
Calcium Dependent ◽  
Membrane Complex ◽  
Isolation And Characterization ◽  
Insoluble Complex ◽  
Marker Proteins

The Triton-insoluble complex from porcine lung membranes has been separated into two distinct subfractions visible as discrete light-scattering bands following buoyant density-gradient centrifugation in sucrose. Both of these detergent-insoluble complexes were enriched in the glycosyl-phosphatidylinositol (GPI)-anchored ectoenzymes alkaline phosphatase, aminopeptidase P and 5´-nucleotidase, and both complexes excluded the polypeptide-anchored ectoenzymes angiotensin-converting enzyme, dipeptidyl peptidase IV and aminopeptidases A and N. The GPI-anchored proteins in both complexes were susceptible to release by phosphatidylinositol-specific phospholipase C. Both complexes were also enriched in cholesterol and glycosphingolipids, and in caveolin/VIP21, although only the higher-density fraction was enriched in the plasmalemmal caveolar marker proteins Ca2+-ATPase and the inositol 1,4,5-trisphosphate receptor. Among the annexin family of proteins, annexins I and IV were absent from the two detergent-insoluble complexes, annexin V was present in both, and annexins II and VI were only enriched in the higher-density fraction. When the metal chelator EGTA was present in the isolation buffers, annexins II and VI dissociated from the higher-density detergent-insoluble complex and only a single light-scattering band was observed on the sucrose gradient, at the same position as for the lower-density complex. In contrast, in the presence of excess calcium only a single detergent-insoluble complex was isolated from the sucrose gradients, at an intermediate density. Thus the detergent-insoluble membrane complex can be subfractionated on the basis of what appears to be calcium-dependent, annexin-mediated, vesicle aggregation into two distinct populations, only one of which is enriched in plasmalemmal caveolar marker proteins.

scholarly journals Regulating Labour Relations in China : The Challenge of Adapting to the Socialist Market Economy

2005 ◽  
Vol 37 (3) ◽  
pp. 753-775
Author(s):  
Pitman B. Potter ◽  
Li Jianyong
Keyword(s):  
Economic Growth ◽  
Trade Unions ◽  
Legal Protection ◽  
Labour Law ◽  
Potential Significance ◽  
Major Step ◽  
Socialist Market Economy ◽  
Labour Relations ◽  
The Relationship ◽  
Socialist Market

This paper examines the new Labour Law of the PRC, effective January 1, 1995, in the light of current and historical conditions of labour relations in China. Provisions regarding the labour contract system and dispute resolution are discussed in greater detail. Issues related to the introduction of collective bargaining and to the relationship between trade unions and the Communist Party are also examined. In their overall assessment, the authors recognize the potential significance of the Labour Law as a major step towards the legal protection of workers' rights, but point out that its effectiveness could be undermined by the preeminent policy of economic growth, by concerns about political control, and by obstacles to full implementation.

Functional heterogeneity with respect to oestrogen treatment in prolactin cell subpopulations separated by Percoll gradient centrifugation

1994 ◽  
Vol 141 (2) ◽  
pp. 251-258 ◽  
Author(s):  
B Velkeniers ◽  
M Kazemzadeh ◽  
L Vanhaelst ◽  
E L Hooghe-Peters
Keyword(s):  
Gradient Centrifugation ◽  
High Density ◽  
Female Rats ◽  
Cell Subpopulation ◽  
Percoll Gradient ◽  
Prolactin Cell ◽  
Prolactin Gene ◽  
Prolactin Mrna

Abstract The effects of oestradiol on prolactin gene expression were studied by quantitative in situ hybridization histochemistry in different prolactin pituitary cell (sub)populations, which had been obtained by separation on a discontinuous Percoll gradient. When cells were incubated in vitro in the presence of oestradiol (10−8 m) for a period of 4, 24, 48 and 72 h, there was an increase in the amount of prolactin mRNA, from 24 h on, only in high-density prolactin cells and lactotrophs of the total cell suspension. In contrast, the amount of prolactin mRNA in lactotrophs of low density did not change upon treatment with oestradiol. Pharmacological treatment with 50 μg oestradiol/day (s.c.) of random cycling female rats in vivo for 14 days increased the total number of prolactin gene-expressing cells and more lactotrophs were recovered at high density after Percoll gradient centrifugation. These results suggest a preferential stimulatory effect of oestradiol on prolactin gene transcription on a subpopulation of lactotrophs. Changes observed in prolactin cell layers after oestradiol treatment in vivo may represent a preferential effect in situ on a particular mammotroph cell subpopulation. Journal of Endocrinology (1994) 141, 251–258

Sperm morphology and IVF pregnancy rate: comparison between Percoll gradient centrifugation and swim-up procedures

1991 ◽  
Vol 6 (4) ◽  
pp. 581-588 ◽  
Author(s):  
P. Van Der Zwalmen ◽  
G. Bertin-Segal ◽  
L. Geerts ◽  
C. Debauche ◽  
R. Schoysman
Keyword(s):  
Pregnancy Rate ◽  
Sperm Morphology ◽  
Gradient Centrifugation ◽  
Percoll Gradient ◽  
Rate Comparison

scholarly journals ELECTRON MICROSCOPIC EVIDENCE FOR PURIFICATION OF COCONUT ROOT (WILT) DISEASE PHYTOPLASMA

CORD ◽  
2002 ◽  
Vol 18 (01) ◽  
pp. 34
Author(s):  
M. Mayilvaganan ◽  
J. J. Solomon
Keyword(s):  
Plant Material ◽  
Gradient Centrifugation ◽  
Spherical Shape ◽  
Electron Microscopic Examination ◽  
Wilt Disease ◽  
Diseased Plant ◽  
Percoll Gradient ◽  
Electron Microscopic ◽  
Centrifugation Method ◽  
Discontinuous Percoll Gradient

Root (wilt) disease phytoplasma was purified from diseased coconut tissues using discontinuous Percoll gradient centrifugation method. Crude sap prepared from coconut was layered on a discontinuous Percoll gradient of 15, 30, 50 and 60%(v/v). After centrifugation at 20,000 g for 30 min, the turbid fraction formed on the top of 30% gradient in the diseased plant material was recovered, processed and fixed for electron microscopy. Electron microscopic examination of sections prepared from purified preparation of diseased plant material showed typical cells of root (wilt) phytoplasma with heterogeneous sizes and more or less spherical shape that are similar to those found in sieve elements of diseased tissues and salivary glands of infective (viruliforms) insect vectors. These purified phytoplasma bodies showed trilaminar membrane with internal materials of ribosome granules and DNA fibrils. However, the yield in terms of number of cells was fewer and in addition to intact bodies, free membranes and empty bodies lacking internal contents also were observed.

scholarly journals Analysis of the role of p200-containing vesicles in post-Golgi traffic.

1996 ◽  
Vol 7 (6) ◽  
pp. 961-974 ◽  
Author(s):  
E Ikonen ◽  
R G Parton ◽  
F Lafont ◽  
K Simons
Keyword(s):  
Gradient Centrifugation ◽  
Equilibrium Density ◽  
Apical Surface ◽  
Transport Pathways ◽  
Permeabilized Cells ◽  
Influenza Hemagglutinin ◽  
Streptolysin O ◽  
Marker Proteins ◽  
Viral Marker ◽  
Golgi Network

p200 is a cytoplasmic protein that associates with vesicles budding from the trans-golgi network (TGN). The protein was identified by a monoclonal antibody AD7. We have used this antibody to analyze whether p200 functions in exocytic transport from the TGN to the apical or basolateral plasma membrane in Madin-Darby canine kidney cells. We found that transport of the viral marker proteins, influenza hemagglutinin (HA) to the apical surface or vesicular stomatitis virus glycoprotein (VSV G) to the basolateral surface in streptolysin O-permeabilized cells was not affected when p200 was depleted from both the membranes and the cytosol. When vesicles isolated from perforated cells were analyzed by equilibrium density gradient centrifugation, the p200 immunoreactive membranes did not comigrate with either the apical vesicle marker HA or the basolateral vesicle marker VSV G. Immunoelectron microscopy of perforated and double-labeled cells showed that the p200 positive vesicular profiles were not labeled by antibodies to HA or VSV G when the viral proteins were accumulated in the TGN. Furthermore, the p200-decorated vesicles were more electron dense than those labeled with the viral antibodies. Together, these results suggest that p200 does not function in the transport pathways that carry HA from the TGN to the apical surface or VSV G from the TGN to the basolateral surface.

Separation of Isospora (Toxoplasma) gondii cysts and cystozoites from mouse brain tissue by continuous density - gradient centrifugation

Parasitology ◽  
1981 ◽  
Vol 83 (1) ◽  
pp. 103-108 ◽  
Author(s):  
A. W. C. A. Cornelissen ◽  
J. P. Overdulve ◽  
J. M. Hoenderboom
Keyword(s):  
Toxoplasma Gondii ◽  
Brain Tissue ◽  
Density Gradient ◽  
Infected Mouse ◽  
Mouse Brain ◽  
Density Gradient Centrifugation ◽  
Gradient Centrifugation ◽  
Percoll Gradient ◽  
Isolation And Purification ◽  
Reproducible Method

SUMMARYA simple, quick and reproducible method consisting of density-gradient centrifugation of homogenized infected mouse brain tissue on Percoll is described for the isolation and purification of cysts of Isospora (Toxoplasma) gondii. A 100% recovery of cysts, with 74·2% in a single fraction with a specific gravity of 1·056, was obtained by overlaying homogenates of infected mouse brains on a pre-formed Percoll gradient and centrifugation at low g forces. With this procedure recovery was independent of the age of the cysts. Titration of purified cystozoites showed there to be no loss of infectivity.

scholarly journals Sickling-induced binding of immunoglobulin to sickle erythrocytes

Blood ◽  
1988 ◽  
Vol 71 (3) ◽  
pp. 636-639 ◽  
Author(s):  
GA Green ◽  
VK Kalra
Keyword(s):  
Flow Cytometry ◽  
Gradient Centrifugation ◽  
Protein A ◽  
Fluorescein Isothiocyanate ◽  
Low Density ◽  
Autologous Plasma ◽  
Sickle Cells ◽  
Sickle Erythrocytes

Abstract Previously we demonstrated that sickle erythrocytes sedimenting at high densities after gradient centrifugation contain higher levels of surface immunoglobulin bound in vivo in comparison to low-density erythrocytes from the same patient. The present study examines the possibility that binding of autologous IgG to sickle erythrocytes may be associated with the sickling phenomenon. In the present study we subjected low-density erythrocytes to prolonged sickling under nitrogen in the presence of platelet-poor autologous plasma with added glucose for 24 hours (37 degrees C). After reoxygenation IgG bound in vitro was quantified by a nonequilibrium 125iodinated protein A-binding assay and by flow cytometry. Results show that sickle erythrocytes incubated under nitrogen bound significantly (P less than .001) more IgG, 439 +/- 41, molecules of IgG per cell (mean +/- SD) compared with sickle cells incubated under oxygenation (227 +/- 12 molecules of IgG per red cell) or compared with 196 +/- 26 molecules IgG per cell for untreated sickle cells. In contrast, normal erythrocytes incubated in autologous plasma exhibited no detectable IgG binding in vitro under either oxygenation or deoxygenation. Flow cytometry shows that deoxygenation of sickle cells generated a two-to-sixfold increase in the subpopulation of brightly fluorescent IgG-positive cells in comparison to oxygenated sickle cells and a 13.5% +/- 3.1% (mean +/- SD) increase in median fluorescence intensity for fluorescein isothiocyanate-labeled deoxygenated sickled cells compared with labeled oxygenated sickle cells. Our studies demonstrate that prolonged sickling will induce in vitro binding of autologous IgG to sickle erythrocytes. These findings indicate that sickle erythrocytes may be unique when compared with erythrocytes from other nonimmunologic hemolytic anemias or senescent red cells in that the primary events producing surface antigens recognized by autoantibody may include the sickling process. These findings also suggest that sickling in vivo may generate membrane alterations in sickle erythrocytes that lead to cumulative binding of autoantibody in vivo.

Sign in / Sign up

Export Citation Format

Share Document