Apoptosis: a basic biological phenomenon with wide-ranging implications in tissue kinetics.
TLDR
Apoptosis seems to be involved in cell turnover in many healthy adult tissues and is responsible for focal elimination of cells during normal embryonic development, and participates in at least some types of therapeutically induced tumour regression.Abstract:
The term apoptosis is proposed for a hitherto little recognized mechanism of controlled cell deletion, which appears to play a complementary but opposite role to mitosis in the regulation of animal cell populations. Its morphological features suggest that it is an active, inherently programmed phenomenon, and it has been shown that it can be initiated or inhibited by a variety of environmental stimuli, both physiological and pathological.The structural changes take place in two discrete stages. The first comprises nuclear and cytoplasmic condensation and breaking up of the cell into a number of membrane-bound, ultrastructurally well-preserved fragments. In the second stage these apoptotic bodies are shed from epithelial-lined surfaces or are taken up by other cells, where they undergo a series of changes resembling in vitro autolysis within phagosomes, and are rapidly degraded by lysosomal enzymes derived from the ingesting cells.Apoptosis seems to be involved in cell turnover in many healthy adult tissues and is responsible for focal elimination of cells during normal embryonic development. It occurs spontaneously in untreated malignant neoplasms, and participates in at least some types of therapeutically induced tumour regression. It is implicated in both physiological involution and atrophy of various tissues and organs. It can also be triggered by noxious agents, both in the embryo and adult animal.read more
Citations
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Journal ArticleDOI
The hallmarks of cancer.
TL;DR: This work has been supported by the Department of the Army and the National Institutes of Health, and the author acknowledges the support and encouragement of the National Cancer Institute.
Journal ArticleDOI
Apoptosis: A Review of Programmed Cell Death
TL;DR: The goal of this review is to provide a general overview of current knowledge on the process of apoptosis including morphology, biochemistry, the role of apoptoses in health and disease, detection methods, as well as a discussion of potential alternative forms of apoptotic proteins.
Journal ArticleDOI
Identification of programmed cell death in situ via specific labeling of nuclear DNA fragmentation.
TL;DR: The extent of tissue-PCD revealed by this method is considerably greater than apoptosis detected by nuclear morphology, and thus opens the way for a variety of studies.
Book ChapterDOI
Cell death : the significance of apoptosis
TL;DR: It has proved feasible to categorize most if not all dying cells into one or the other of two discrete and distinctive patterns of morphological change, which have, generally, been found to occur under disparate but individually characteristic circumstances.
Journal ArticleDOI
The biochemistry of apoptosis
TL;DR: The basic components of the death machinery are reviewed, how they interact to regulate apoptosis in a coordinated manner is described, and the main pathways that are used to activate cell death are discussed.
References
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Journal ArticleDOI
Death in Embryonic Systems
TL;DR: The present exploration has revealed that death during embryogenesis serves utilitarian goals in some instances, at least, that its occurrence is subject to control by factors of the immediate cellular and humoral environment.
Book
Lymphatics, lymph and the lymphomyeloid complex,
TL;DR: The lymphatics, lymph and the lymphomyeloid complex is a complex of lymphocytes that combines the components of the Tournaisian immune system with those of other immune cells to form T lymphocytes.
Journal ArticleDOI
Cell loss as a factor in the growth rate of human tumours
TL;DR: Ce genre of calcul est appliquea des tumeurs humaines, en utilisant les donnees publiees sur les temps de doublement de volume and les index de marquage a la thymidine and de the duree of the periode de synthese de l'ADN.