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1

Flow cytometry in mammalian sperm sexing and quality measurement

100%
Bochenek M.
Biotechnologia
|
1998
|
issue 2
119-129
EN
Flow cytometry is a powerful technique for measurements of many structural and functional cell parameters. In sperm analyses it offers several advantages over the formerly used methods: high accuracy, possibility of measuring two or even three parameters simultaneously and analysis of a high number of cells per second. Moreover, at present it is the only technique which allows sperm sorting of X- and Y-fractions with high purity. The paper is a review of the flow cytometry applications in sperm sexing and measurements of quality parameters: membrane integrity, acrosome status, mitochondrial and esterase activity and sperm chromatin structure.
2

Flow cytometry-application in animal biotechnology

80%
Smorag Z., Bochenek M.
Biotechnologia
|
1995
|
issue 3
54-67
EN
Flow cytometry offers several advantages over the formerly used methodologies - hundreds or thousands of cells can be measured per second with high accuracy and reproducibility, rare cells can be detected from a large population.Some of the staining methods preserve cell viability so the reprodctive capacity of the sorted cells can be investigated.In biotechnology, the most popular application of flow cytometry is the DNA analysis e.g. cell cycle, chromosome karyotyping, gene mapping, etc.It is possible to analyse quality of semen and sorting of viable sperm cells.
3

Molecular targets for immunocontraception

80%
Stoyka B., Domagala A., Kurpisz M.
Archivum Immunologiae et Therapiae Experimentalis
|
2003
|
vol. 51
|
issue 1
45-49
EN
An effective contraceptive is necessary in the countries where limiting population growth has become a public policy imperative. Main antigenic targets for contraceptive vaccine development can be listed as following: 1) sperm antigens; 2) zona pellucida antigens; 3) gonadotrophin-releasing hormone; 4) chorionic gonadotrophin; 5) other protein/peptide hormones (follicle-stimulating hormone, luteinising hormone, luteinizing hormone ? releasing hormone); 6) gonadal steroid hormones. New techniques such as an application of monoclonal antibodies, hybridoma and DNA recombinant technologies became useful in search for contraceptive candidates. Current state of development of contraceptive vaccines based on specific antigenic targets and trials in animal/human models are presented in this article.
4

An attempt at comparing external changes taking place during maturation of male mice with the development of the process of spermatogenesis

80%
Wirth-Dzieciolowska E., Sysa P. S., Ponimasz A.
|
EN
Evaluation of the degree of sexual maturation was performed in male mice of two selected lines differing in respect of body weight. Four developmental stages were distinguished: (1) loosening of the skin between the urinary papilla and the anus, (2) projection of the scrotum, (3) descent of the testes to the scrotum, (4) demonstration of sexual drive. Histological examination of the testes revealed that at the first developmental stage the animals had clearly immature gonads. In a few, not numerous, seminiferous tubules spermatogenesis had reached the phase of primary spermatocytes. At the second stage of development the male gonads reached the phase of secondary spermatocytes and sporadically of early spermatids. At the third stage of the animals development, the spermatogenesis observed in numerous cross-sections of the seminiferous tubules reached the spermatid phase and in males at the fourth stage some sperm cells appeared in the lumen of the tubules. A greater diameter of the sperminiferous tubles was demonstrated in the heavy line males than in the light line animals. In males of the heavy line the diameter of the Leydig cells increased between the third and fourth stage. The investigation results suggest that the accepted criteria of determination of sexual maturation stages correspond to various phases of changes taking place in the process of spermatogenesis.
5

Sperm transport after insemination in the Alpine newt (Triturus alpestris, Caudata, Salamandridae)

70%
Osikowwski A.
|
2007
|
vol. 55
|
issue 3-4
109-114
EN
The goal of this study was to test if sperm transport to the spermathecae in the Alpine newt (Triturus alpestris) requires active co-operation of the female. Artificial insemination of anaesthetised female newts was conducted using spermatophores collected from courting males and with sperm duct contents collected from sacrificed males. Sperm was present in the spermathecae of 9 out of 10 females inseminated with the spermatophores but in only 1 out of 8 females inseminated with sperm duct contents. The females of both groups laid some eggs after insemination, and a portion of these eggs in group of females inseminated with spermatophores were fertilized. However, the number of eggs produced by the females was much lower than typical egg-production in newts. The presence of sperm in the spermathecae of females inseminated with spermatophores and lack of sperm in the spermathecae of females inseminated with sperm duct contents suggests that sperm transport is either induced by the substances present in spermatophores and/or that sperm from the sperm duct is not fully mobile in comparison with sperm from the spermatophores.
6

Apoptosis in mammalian sperm

70%
Trzcinska M.
Biotechnologia
|
2006
|
issue 1
82-89
EN
This physiological cell death, also known as programmed cell death, takes place during the entire growth period of an organism. In general, somatic cell apoptosis can be induced through extrinsic mechanisms acting at the plasma membrane, mitochondrial or nuclear levels. Recent studies have demonstrated that apoptosis is an underlying mechanism of germ cell death during normal spermatogenesis and that it is a major mechanism in regulating spermatogenesis of various mammalian species. While apoptosis in somatic cells and in (testicular) spermatocytes and spermatids is well established, the presence and significance of apoptosis in ejaculated animals sperm is still unresolved.
7

The application of in vitro cattle embryo production system to study the influence of elevated temperature on oocyte maturation, fertilization and early embryonic development

61%
Rynkowska A., Rapa?a L., Trzeciak P., Duszewska A. M.
Biotechnologia
|
2011
|
issue 1
45-53
EN
Higher air temperature in summer causes a significant reduction in fertility in cattle. Increase in female body temperature during the period of reproduction by only 2EC, also known as hyperthermia, leads to disturbances in the functioning of the female reproductive system, oocytes maturation, fertilization and embryos development. Particularly sensitive to high temperatures are embryos in the first and second day after fertilization (thermosensitive), but just at third till fifth day after fertilization their resistance to thermal stress significantly increases. Morula-stage and blastocyst-stage bovine embryos are insensitive to elevated temperatures (thermoresistant). Most probably this is due to the increasing number of cells within the embryo and the capacity to activate defense mechanisms based on the synthesis of various factors providing resistance to high temperatures. These factors include heat shock protein 70 (HSP70), antioxidants such as glutathione, and IGF-1. One of the responses of the embryo to elevated temperature is the induction of apoptosis, which is associated with the activation of embryonic genome. Owing to the apoptosis, cells damaged by high temperature may be eliminated from the embryo, which increases their chance of survival. Precise examination of the mechanisms responsible for the development of thermotolerance of preimplantation bovine embryos will enable their protection from the consequences of elevated temperature. The aim of this review is to summarise experiments in which in vitro embryo production system was used to estimate the influence of elevated temperature on cattle fertility.
8

Reproduction biotechnology of farm animals

61%
Smorag Z.
Biotechnologia
|
2002
|
issue 4
30-40
EN
This paper presents the most important research and application of biotechnology of farm animals reproduction: semen sexing, embryo in vitro production, embryonic and somatic cloning and transgenesis.
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