scholarly journals ON THE PERMANENT LIFE OF TISSUES OUTSIDE OF THE ORGANISM

1912 ◽  
Vol 15 (5) ◽  
pp. 516-528 ◽  
Author(s):  
Alexis Carrel
Keyword(s):  
Connective Tissue ◽  
New Techniques ◽  
The Third ◽  
Rate Of Growth ◽  
Active Life ◽  
The Future ◽  
Long Time ◽  
Series Of Experiments

In two series of experiments made at the end of 1911 and at the beginning of 1912, new techniques were developed with the view of investigating the problem of prolonging indefinitely the life of tissues isolated from the organism. These techniques are far from perfect and will doubtless be modified in the future. But they have already permitted the establishment of new facts. Fragments of connective tissue have been kept in vitro in a condition of active life for more than two months. As a few cultures are now eighty-five days old and are growing very actively, it is probable that, if no accident occurs, the life of these cultures will continue for a long time. In some cases the rate of growth of the tissues increased in direct ratio to the age of the culture. Fragments of heart pulsated rhythmically at the beginning of the third month of their life in vitro. These facts show that experiments made with these or with more perfect techniques and followed over long periods of time may lead to the solution of the problem of permanent life of tissues in vitro, and give important information on the characters acquired by tissues liberated from the control of the organism from which they were derived.

Alkohol im Tank – Bio-Kraftstoffe und die Grenzen moderner Mobilität

2004 ◽  
Vol 34 (136) ◽  
pp. 455-468
Author(s):  
Hartwig Berger
Keyword(s):  
Third World ◽  
Fossil Fuel ◽  
Energy Resources ◽  
The Third ◽  
Political Conflicts ◽  
The Future ◽  
Long Time ◽  
Food Market ◽  
The One ◽  
The Third World

The article discusses the future of mobility in the light of energy resources. Fossil fuel will not be available for a long time - not to mention its growing environmental and political conflicts. In analysing the potential of biofuel it is argued that the high demands of modern mobility can hardly be fulfilled in the future. Furthermore, the change into using biofuel will probably lead to increasing conflicts between the fuel market and the food market, as well as to conflicts with regional agricultural networks in the third world. Petrol imperialism might be replaced by bio imperialism. Therefore, mobility on a solar base pursues a double strategy of raising efficiency on the one hand and strongly reducing mobility itself on the other.

Fanning the Embers

2016 ◽  
Author(s):  
Rebecca J. Kinney
Keyword(s):  
Connective Tissue ◽  
Auto Industry ◽  
The Third ◽  
The Future ◽  
The Face

The third chapter examines the story of Detroit’s rebirth through both a reliance on its storied past and the possibilities of the future through an examination of a wildly successful commercial starring Eminem. It provides the connective tissue between the storied past of Detroitas as a location of workers and the contemporary narrative of a city on the rise. At its center is the mythic tale provided by the 2011 Chrysler “Born of Fire” commercial. The narrative tale of a rebirth of a city, and by extension the American auto industry, in the face of epic decline makes the story of Detroit the ultimate comeback tale—a phoenix rising from the ashes of destruction.

scholarly journals CONTRIBUTIONS TO THE STUDY OF THE MECHANISM OF THE GROWTH OF CONNECTIVE TISSUE

1913 ◽  
Vol 18 (3) ◽  
pp. 287-298 ◽  
Author(s):  
Alexis Carrel
Keyword(s):  
Connective Tissue ◽  
Culture Medium ◽  
Dynamic Condition ◽  
Real Life ◽  
Rate Of Growth ◽  
Independent Life ◽  
Tissue Cells ◽  
Chick Embryo Heart ◽  
Embryo Heart

When connective tissue cells have been cultivated for a certain length of time in a medium which has been repeatedly changed, a definite relation arises between the rate of growth of the cells and the composition of the medium. It is possible, by adding to the culture medium a given quantity of certain substances, such as embryonic juices, to foresee the extent to which a fragment of tissue composed of a given strain of cells will increase in a given time. The rate of growth of a strain of cells can be accelerated or retarded by the addition to the medium of activating or retarding substances. The dynamic condition of a strain of connective tissue cells, which have been living in a given medium for some time, is not a definitely acquired characteristic, but a temporary state, and is the product or function of the medium in which the cells are living, and is readily modified merely by altering the composition of the medium. A knowledge of the characteristics of the growth of connective tissue described has led to a new result,—the indefinite proliferation of a strain of connective tissue cells outside of the organism. The strain of connective tissue originally obtained from a fragment of chick embryo heart, which had been pulsating in vitro for 104 days, was still actively alive after sixteen months of independent life and more than 190 passages. The rate of proliferation of the connective tissue sixteen months old equalled and even exceeded that of fresh connective tissue taken from an eight day old embryo. It appears, therefore, that time has no effect on the tissues isolated from the organism and preserved by means of the technique described above. During the sixteenth month of life in vitro the cells increased rapidly in number and were able in a short time to produce a large quantity of new tissue. This fact, therefore, definitely demonstrates that the tissues were not in a state of survival, as was the case in certain earlier experiments, but in a condition of real life, since the cells of which they were composed, like microorganisms, multiplied indefinitely in the culture medium.

scholarly journals ACTION OF SERUM ON FIBROBLASTS IN VITRO

1923 ◽  
Vol 37 (6) ◽  
pp. 759-765 ◽  
Author(s):  
Alexis Carrel ◽  
Albert H. Ebeling
Keyword(s):  
Connective Tissue ◽  
Serum Proteins ◽  
Embryonic Tissue ◽  
Tyrode Solution ◽  
Food Material ◽  
Nitrogenous Compounds ◽  
Rate Of Growth

It may be concluded that, under the conditions of the experiments: 1. The duration of life of fibroblasts is not altered by the presence of 7 per cent serum in a medium composed of fibrin and Tyrode solution, but is slightly decreased when the concentration of the serum reaches 25 per cent. 2. Fibroblasts cultivated in serum or in Tyrode solution are only in a condition of survival; they do not build up new protoplasm from the serum proteins and their mass does not increase. 3. When embryonic tissue juice is added to the medium, the tissues increase in mass. But the rate of growth is the same in media containing 0 per cent and 10 per cent serum. In 25 per cent serum, however, the rate of growth slightly decreases. Even in the presence of embryonic tissue juice, serum does not increase the rate of growth of connective tissue. 4. The nitrogenous compounds contained in serum are not used as food material by fibroblasts growing in vitro.

scholarly journals THE CULTIVATION OF HUMAN TISSUE IN VITRO

1914 ◽  
Vol 19 (6) ◽  
pp. 593-602 ◽  
Author(s):  
Joseph R. Losee ◽  
Albert H. Ebeling
Keyword(s):  
Connective Tissue ◽  
Human Tissue ◽  
Active Life

A strain of human connective tissue was kept in a condition of active life in vitro for more than two months. When a medium has been devised the composition of which is more constant, it is reasonable to suppose that human connective tissue can be cultivated in vitro for an indefinite period.

scholarly journals MEASUREMENT OF THE GROWTH OF TISSUES IN VITRO

1921 ◽  
Vol 34 (3) ◽  
pp. 231-243 ◽  
Author(s):  
Albert H. Ebeling
Keyword(s):  
Connective Tissue ◽  
Rate Of Growth

1. A technique has been developed by which two fragments of tissue, put in identical media, can grow at almost the same rate. 2. A method of measuring the growing tissue is described. 3. The differences observed in the rate of growth of two fragments of the 9 year old strain of connective tissue, cultivated in identical media and measured according to this technique, are less than 10 per cent.

scholarly journals A STRAIN OF CONNECTIVE TISSUE SEVEN YEARS OLD

1919 ◽  
Vol 30 (6) ◽  
pp. 531-537 ◽  
Author(s):  
Albert H. Ebeling
Keyword(s):  
Connective Tissue ◽  
Culture Medium ◽  
Rate Of Growth ◽  
Tissue Cells

1. A strain of connective tissue is still very active after more than 7 years of life in vitro. 2. The rate of growth of the fragments of tissue can be measured accurately and used for testing the action of many different factors on the growth of connective tissue cells. 3. The rate of growth of the strain is at least as rapid as it was 5 years ago, and may be more active. 4. The connective tissue cells appear to have the power of multiplying indefinitely in a culture medium, as do microorganisms.

In vitro fertilization in inbred BALB/c mice II: effects of lactate, osmolarity and calcium on in vitro capacitation

Zygote ◽  
2008 ◽  
Vol 16 (3) ◽  
pp. 259-270 ◽  
Author(s):  
Seiji Kito ◽  
Yuki Ohta
Keyword(s):  
In Vitro Fertilization ◽  
Choline Chloride ◽  
Dependent Manner ◽  
Sperm Capacitation ◽  
Vitro Fertilization ◽  
The Third ◽  
Series Of Experiments ◽  
Dose Dependent ◽  
Human Tubal Fluid

SummaryTo elucidate requirements for in vitro sperm capacitation in inbred BALB/c mice, osmolarity, calcium and lactate were optimized using modified simplex optimization medium (mKSOM). Modified human tubal fluid (mHTF), a capacitation-supporting medium, was used as a control. In the first series of experiments, the effects of calcium and osmolarity were studied in the presence of lactate. Although preincubation with ≥5 mM CaCl2 improved fertilization after insemination significantly, it was still significantly lower than incubation with mHTF. To obtain fertilization at the equivalent levels to that of mHTF, isotonic osmolarity (305 mOsmol) was required. Trehalose, an osmotic reagent, could substitute for NaCl partially. In the second series of experiments, the effects of lactate were examined using a concentration of 5 mM calcium and isotonic osmolarity. Preincubation with ≤2.5 mM lactate increased fertilization significantly (>75%), as well as the percentages of B (capacitated) pattern sperm (≥40%) in chlortetracycline (CTC) staining, as compared with incubation in mHTF (46% and 28%, respectively; p < 0.05). In the third series of experiments, the effects of osmolarity and calcium in the absence of lactate were examined. An increase in osmolarity during sperm preincubation increased both fertilization and B-pattern sperm significantly in a dose-dependent manner. Trehalose, sucrose and choline chloride could substitute for NaCl. An increase in CaCl2 concentration during preincubation had no effect on fertilization, but this increase reduced the percentages of B-pattern sperm. In vitro capacitation of inbred BALB/c mice is sensitive to lactate and osmolarity, but that sensitivity for calcium varies depending on the presence or absence of lactate.

Induction and Differentiation of Dental Epithelium in Vivo and in Vitro

1982 ◽  
Vol 40 ◽  
pp. 142-145
Author(s):  
E. J. Kollar
Keyword(s):  
Connective Tissue ◽  
Oral Mucosa ◽  
Basal Lamina ◽  
Functional Derivatives ◽  
Specific Source ◽  
Dental Epithelium ◽  
Connective Tissue Stroma

The differentiation and maintenance of many specialized epithelial structures are dependent on the underlying connective tissue stroma and on an intact basal lamina. These requirements are especially stringent in the development and maintenance of the skin and oral mucosa. The keratinization patterns of thin or thick cornified layers as well as the appearance of specialized functional derivatives such as hair and teeth can be correlated with the specific source of stroma which supports these differentiated expressions.

Some Structural Features of Metaphase Chromosomes of Mice and Men

1967 ◽  
Vol 25 ◽  
pp. 190-191
Author(s):  
Godfrey C. Hoskins ◽  
Betty B. Hoskins
Keyword(s):  
Electron Microscopy ◽  
Electron Micrographs ◽  
Structural Features ◽  
Metaphase Chromosomes ◽  
The Future ◽  
Of Mice And Men ◽  
Mouse Cells ◽  
Human And Mouse

Metaphase chromosomes from human and mouse cells in vitro are isolated by micrurgy, fixed, and placed on grids for electron microscopy. Interpretations of electron micrographs by current methods indicate the following structural features.Chromosomal spindle fibrils about 200Å thick form fascicles about 600Å thick, wrapped by dense spiraling fibrils (DSF) less than 100Å thick as they near the kinomere. Such a fascicle joins the future daughter kinomere of each metaphase chromatid with those of adjacent non-homologous chromatids to either side. Thus, four fascicles (SF, 1-4) attach to each metaphase kinomere (K). It is thought that fascicles extend from the kinomere poleward, fray out to let chromosomal fibrils act as traction fibrils against polar fibrils, then regroup to join the adjacent kinomere.

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