Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 6

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  modele in vitro
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
1

Zastosowanie technik hodowli przestrzennych [3D] w badaniach biologii gruczolu mlekowego bydla

100%
Kozlowski M., Motyl T.
Medycyna Weterynaryjna
|
2007
|
tom 63
|
nr 11 Supl.
1417-1420
The mammary gland has been extensively studied for over a century. However, the major contribution to our current knowledge of mammary gland biology has been made mostly by studying the mammary gland of humans and rodents, while ruminant models have lagged behind. During the last years, a variety of in vitro approaches have been employed to understand the regulation of mammary gland growth and morphogenesis during different developmental and physiological stages. There are only a few immortalized cell lines of bovine mammary gland epithelium. Unfortunately only three of them are IGF and EGF sensitive, which is very important in mammary gland development in vivo. Monolayer culture models are easy and convenient to set up but they lack the three-dimensional microenvironment of intact tissue. This review describes the three-dimensional (3-D) cell culture system, which has recently been widely used. Bovine primary mammary epithelium cell cultures and some immortalized cell lines plated on an extracellular matrix form functional acini-like structures. This model mimics organization and differentiation of an intact tissue and can be very useful in the investigation of bovine mammary gland biology.
2

Metody badania aktywnosci inwazyjnej komorek nowotworowych

100%
Madeja Z.
Postępy Biologii Komórki. Suplement
|
2001
|
tom 16
81-95
3

Porownanie aktywnosci metabolicznej bioreaktora watrobowego z perfundowana watroba

86%
Karlik W., Sztuk P., Bakala A., Glowala A., Grono D., Wiechetek M.
Medycyna Weterynaryjna
|
2008
|
tom 64
|
nr 03
354-358
The aim this study was to compare metabolic activity of a hollow fiber bioreactor with a perfused liver. A special construction of a hollow fiber bioreactor was used with freshly isolated rat hepatocytes. After isolation, hepatocytes were incubated in the bioreactor for the duration of 3 hrs in the following conditions: 100 ml medium Hanks Balances Salts Solution supplemented with 4% albumin, 2 mM ornithine, 10 mM ammonium chloride and 6 mM ethanol were used; the medium was perfused in a circulated system for 25 ml/min; samples of the medium were taken to estimate ammonia, urea, glucose, lactate, ethanol, AST and ALT activity before and after 5 min and every 15 min of perfusion time. The same experimental condition was used in the perfused rat liver system. Utilization of ammonia was different in both systems and amounted to: 8.89 and 5.23 µmol/h/g hepatocytes in the bioreactor and perfused liver, respectively. Urea production was: 2.35 and 8.22 µmol/h/g hepatocytes, respectively. The largest differences between the compared systems were observed in the glucose and lactate metabolism. The bioreactor did not release glucose and lactate during the entire time of perfusion. In contrast, perfused liver intensively released glucose (31.32 µmol/hr/g cells) and produced lactate (29.42 µmol/hr/g cells). On the other hand, there was no statistically significance difference in the rate of ethanol metabolism between both systems, which amounted to 2.55 and 2.04 umol/h/g hepatocytes in the bioreactor and perfused liver, respectively. The results indicate that a bioreactor with freshly isolated hepatocytes is not bioequivalent to a perfused liver if estimation is made on the basis of ureogenesis and/or glucose utilization. However, ethanol utilization gives evidence that the metabolic activity of the bioreactor is comparable with a perfused liver. On the basis of the obtained results it can be concluded that the difference in metabolic activity of the bioreactor and perfused liver is connected with catabolic state and disturbances of energy metabolism in freshly isolated hepatocytes. In such a condition HBSS is not the proper medium for the recovery of homeostasis. To estimate the metabolic activity of freshly isolated hepatocytes cultivated in various in vitro systems such as a marker of model usefulness it is suggested to use the activity of inducible enzymes, but not constituent enzymes.
4

Rola autofagii w mammogenezie gruczolu mlekowego krow na modelu mammosfer

86%
Sobolewska A., Gajewska M., Motyl T.
Medycyna Weterynaryjna
|
2010
|
tom 66
|
nr 04
222-227
Progress in studies concerning the process of mammogenesis have been stimulated by the development of the three-dimensional (3D) culture systems, which enable mammary epithelial cells to form structures mimicking the alveoli of mammary gland in vivo. Mammary epithelial cells (MECs) supported on a laminin-rich extracellular matrix (ECM) form 3D acinar structures - mammospheres - which mature to form polarized and functional monolayers surrounding a lumen and have the ability to produce milk proteins. These structures develop an axis of apico-basal polarity, subsequently become unresponsive to proliferative signals, and finally a bona fide lumen is formed by cavitation, involving the removal of centrally localized cells via multiple cell death processes. Lumen formation is associated with the selective apoptosis of centrally located cells. Autophagy, which is a process responsible for maintaining cell homeostasis, also seems to be crucial in mammary gland development and remodeling. This review describes the role of autophagy in the formation of acinar structures by mammary epithelial cells. Studies on MECs from different species (human, mouse, cow) cultured on Matrigel™ have shown the protective role of autophagy in centrally located cells of differentiating mammospheres. Autophagy seems to be the cells’ first response to the lack of contact with ECM, which in consequence leads to apoptotic cell death, anoikis, and lumen formation in developing alveoli.
5
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Przeżywalność mikroorganizmów probiotycznych w modelu in vitro układu pokarmowego drobiu

72%
Markowiak-Kopec P., Slizewska K.
Żywność Nauka Technologia Jakość
|
2019
|
tom 26
|
nr 3
6

Regulacja autofagii przez hormony i czynniki wzrostu w mammogenezie gruczołu mlekowego krów na modelu mammosfer

72%
Sobolewska A., Plucienniczak G., Gajewska M.
Medycyna Weterynaryjna
|
2013
|
tom 69
|
nr 02
Autophagy is an important cellular process responsible for the maintenance of homeostasis in the mammary gland during its development and remodeling. The main function of autophagy is to degrade long-lived proteins and damaged organelles in double-membrane autophagic vacuoles containing hydrolytic enzymes. This process is also involved in the regulation of cell development and death. Three-dimensional (3D) cell cultures made it possible to recreate in vitro the process of alveoli formation by mammary epithelial cells (MECs). When cultured on extracellular matrix (ECM) components, MECs form 3D acini structures called mammospheres, composed of a single layer of polarized cells and a hollow lumen in the center of the acini. It has been shown that during the process of mammosphere formation, autophagy is induced in the centrally located cells in response to the stress related to their loss of contact with the ECM. Studies have shown that the induction of autophagy is augmented in the presence of sex steroids, which regulate cell survival during starvation conditions. Additionally, these hormones control the process of lumen formation, regulating the rate of apoptotic death in mammospheres. TGF-â1 also induces autophagy in 3D cultures, but the presence of this cytokine inhibits the development of acinar structures. On the other hand, IGF-I stimulates the growth of mammospheres, inducing autophagy in the numerous cells located in the centre of acinar structures, where the availability of nutrition is insufficient. The present review article describes some latest studies that point to the role of the close regulation of autophagy by endocrine and intramammary signals during mammogenesis.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.