Cultivation in Vitro of Excised Pea Roots

1937 ◽  
Vol 99 (1) ◽  
pp. 144-170 ◽  
Author(s):  
James Bonner ◽  
Fred Addicott
1980 ◽  
Vol 152 (6) ◽  
pp. 1596-1609 ◽  
Author(s):  
H W Murray ◽  
Z A Cohn

The capacity of 15 separate populations of mouse peritoneal macrophages to generate and release H2O2 (an index of oxidative metabolism) was compared with their ability to inhibit the intracellular replication of virulent Toxoplasma gondii. Resident macrophages and those elicited by inflammatory agents readily supported toxoplasma multiplication and released 4-20X less H2O2 than macrophages activated in vivo by systemic infection with Bacille Calmette-Guérin or T. gondii, or by immunization with Corynebacterium parvum. Immunologically activated cells consistently displayed both enhanced H2O2 production and antitoxoplasma activity. Exposure to lymphokines generated from cultures of spleen cells from T. gondii immune mice and toxoplasma antigen preserved both the antitoxoplasma activity and the heightened H2O2 release of toxoplasma immune and immune-boosted macrophages, which otherwise were lost after 48-72 h of cultivation. In vitro activation of resident and chemically-elicited cells by 72 h of exposure to mitogen- and antigen-prepared lymphokines, conditions that induce trypanocidal (5) and leishmanicidal activity (14), stimulated O2- and H2O2 release, and enhanced nitroblue tetrazolium reduction in response to toxoplasma ingestion. Such treatment, however, failed to confer any antitoxoplasma activity, indicating that intracellular pathogens may vary in their susceptibility to macrophage microbicidal mechanisms, including specific oxygen intermediates. In contrast, cocultivating normal macrophages with lymphokine plus heart infusion broth for 18H rendered these cells toxoplasmastatic. This in vitro-acquired activity was inhibited by scavengers of O2-, H2O2, OH., and 1O2, demonstrating a role for oxidative metabolites in lymphokine-induced enhancement of macrophage antimicrobial activity. These findings indicate that augmented oxidative metabolism is an consistent marker of macrophage activation, and that oxygen intermediates participate in the resistance of both in vivo- and vitro-activated macrophages toward the intracellular parasite, T. gondii.


1922 ◽  
Vol 36 (4) ◽  
pp. 379-384 ◽  
Author(s):  
Albert Fischer

1. A strain of cartilage cells, obtained from the pars cartilago scleræ of the eye of chick embryos, has been cultivated for more than 3 months in vitro. 2. The initial growth of the cartilage was possible only on the free surface of the coagulum. 3. The hyaline substance disappeared during cultivation in vitro. The succeeding stages of a transformation from small, lymphocyte-like cells into large, spindle-shaped cells were observed. The cartilage cells were spindle-shaped and grew in close contact, forming thin membranes. In surface-grown cartilage cells, the nucleus, usually containing one large nucleolus, stained less deeply than the cytoplasm. 4. The rate of growth of cartilage was slower than that of fibroblasts and epithelium. After cultivation on the surface of the coagulum, the cartilage cells could multiply even when embedded in the coagulum. But their growth was less extensive and uniform.


2012 ◽  
pp. 141-150
Author(s):  
Marija Markovic ◽  
Milos Tanasic ◽  
Nevena Stojic ◽  
Radivoje Bulatovic ◽  
Marta Jovic ◽  
...  

This paper succesfully investigated the possibility of modification of the micropropagation protocol of Phalaenopsis sp. with an aim to simplify the procedure and reduce the costs. The obtained results show that some medium components can be succesfully omitted (coconut water, glutamine, 2-morpholinoethanesulfonic acid) and some of them (peptone) can be replaced with a cheaper constituent (soy flour) while preserving the quality of the obtained microplants. The multiplication rate was 7,6 shoots per explant after the period of 150 days of cultivation in vitro. On the same medium 60% of explants were rooted and roots were mostly well developed.


Blood ◽  
1999 ◽  
Vol 94 (1) ◽  
pp. 127-138 ◽  
Author(s):  
Agnieszka M. Lichanska ◽  
Catherine M. Browne ◽  
Gregory W. Henkel ◽  
Kathleen M. Murphy ◽  
Michael C. Ostrowski ◽  
...  

During mouse embryogenesis, macrophage-like cells arise first in the yolk sac and are produced subsequently in the liver. The onset of liver hematopoiesis is associated with the transition from primitive to definitive erythrocyte production. This report addresses the hypothesis that a similar transition in phenotype occurs in myelopoiesis. We have used whole mount in situ hybridization to detect macrophage-specific genes expressed during mouse development. The mouse c-fms mRNA, encoding the receptor for macrophage colony-stimulating factor (CSF-1), was expressed on phagocytic cells in the yolk sac and throughout the embryo before the onset of liver hematopoiesis. Similar cells were detected using the mannose receptor, the complement receptor (CR3), or the Microphthalmia transcription factor (MITF) as mRNA markers. By contrast, other markers including the F4/80 antigen, the macrophage scavenger receptor, the S-100 proteins, S100A8 and S100A9, and the secretory product lysozyme appeared later in development and appeared restricted to only a subset of c-fms–positive cells. Two-color immunolabeling on disaggregated cells confirmed that CR3 and c-fmsproteins are expressed on the same cells. Among the genes appearing later in development was the macrophage-restricted transcription factor, PU.1, which has been shown to be required for normal adult myelopoiesis. Mice with null mutations in PU.1 had normal numbers of c-fms–positive phagocytes at 11.5dpc. PU.1(−/−) embryonic stem cells were able to give rise to macrophage-like cells after cultivation in vitro. The results support previous evidence that yolk sac–derived fetal phagocytes are functionally distinct from those arising in the liver and develop via a different pathway.


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