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Books > Science & Mathematics > Biology, life sciences > Human biology & related topics > General
Scientists are deciphering the biology of the tumor cell at a level
of detail that would have been hard to imagine just a decade or so
ago. The development of high-throughput DNA sequencing and genomics
technologies have allowed an understanding of the development,
growth, survival, and spread of cancer cells in the body. From this
information, we now have a basic blueprint or roadmap of how a
single damaged cell can develop into a pre-malignant lesion, a
primary tumor, and finally, a lethal tumor that may spread
throughout the body and resist both medical therapy and host immune
responses. In this book, we provide an overview of our current
understanding of this cancer blueprint, which has been aided both
by the study of familial cancer syndromes, in vitro studies of
cancer cells, and animal models. Three classes of genes have
emerged from these studies: tumor suppressor genes needed for
normal growth control and DNA repair; oncogenes that regulate cell
growth and survival, and epigenetic modifiers, enzymes that
regulate the modification of DNA and the proteins that form
chromatin. Each of these three classes of genes is mutated or
altered at least once in virtually all malignant cancer cells.
Current technologies permit the DNA sequencing of cancer exomes
(coding gene sequencing), whole genomes, transcriptome (all
expressed genes), and DNA methylation profiling. These studies show
that all tumors have unique constellations of mutated, rearranged,
amplified, and deleted genes. Single-cell sequencing further shows
that there is extensive variation in individual cells in the tumor;
that cancers evolve, and have many of the properties of a
multi-cellular entity. Lastly, cancer cells, through mutations in
epigenetic modifiers, can reprogram the genome and unlock entire
developmental and gene expression pathways to adapt and survive in
changing conditions. This reprogramming allows the tumor to elude
the host body's defenses, radiotherapy, chemotherapy, and targeted
therapy that we use in cancer treatment. Understanding this cancer
blueprint paves the way for the development of future therapies to
treat and eliminate cancer.
The lymphatic system develops and functions in parallel with the
blood circulatory system (termed the "hemovasculature") and
accomplishes transport of interstitial fluids, dietary lipids, and
reverse transport of cholesterol, immune cells, and
antigens-providing a critical homeostatic fluid balance and
transmission of immune cells and mediators back to the
cardiovascular system. Although the daily flow of lymph (normally
1-2 L/day under unstressed conditions) is far lower than that of
daily blood flow (which is 7,500 L/day), without the adequate
functioning of the lymphatics, virtually all organs and tissues
would acutely suffer many different physical and inflammatory
stresses ranging from edema to organ system failure. Although blood
and lymphatic vessels often form in anatomic parallels to one
another, our knowledge of the workings of the lymphatic system, the
fine structure of lymphatic networks, how they function in
different organs, and how they are regulated physiologically and
immunologically are far from parallel; our knowledge of the
lymphatic system still remains at only a tiny fraction of what is
understood about the cardiovascular system. Although both the
cardiovascular and lymphatic systems are important transport
systems, what they transport and how they transport and propel
these very different cargoes could not be more dissimilar. This
book provides an overview of the history of the discovery (and
re-discovery) of the components of the lymphatic system, lymphatic
anatomy, physiological functions of lymphatics, molecular features
of the lymphatic system, and clinical perspectives involving
lymphatics which may be of interest to scientists, clinicians,
patients, and the lay public. We provide a current understanding of
some of the more important structural similarities and differences
between lymphatics and the blood vascular system, their coordinated
control by angiogenic and hemangiogenic growth factors and other
modulators, the fate and lineage determinants which control
lymphatic development, and the roles that lymphatics may play in
several different diseases.
We are a restless, world-changing species. We are the only organism
that combines a multitude of abilities to harness the rules of
nature, continuously manipulating our environment, its resources
and even our own bodies to fit our ever-changing needs and desires.
What is it that enables us to share some 99 percent of DNA as well
as some basic behaviors with other organisms, yet at the same time
be so different and powerful?Coalescing understandings driven from
biology, psychology, anthropology, history and more, Ben David
addresses the above question using a new paradigm: The Gordian knot
between five human traits - imagination, creative making, complex
communication, change and intergenerational transfer - evolutionary
developed and co-amplified as the ultra-complex system called Homo
sapiens. Weaving personal stories with professional experience, Ben
David narrates innovative definitions of technology, education,
science and their co-dependence; emphasizes their roles in the
development of human societies; deliberates their implications on
everyday life; discusses the crucial role of science education; and
offers a fresh look at who we are as the leading species on this
planet.Dr Liat Ben David is the CEO of the Davidson Institute of
Science Education, the educational arm of Israel's acclaimed
Weizmann Institute of Science. She holds a PhD in Molecular Biology
and has more than 30 years of experience in the field of STEM
education. Ben David teaches regularly in various spheres,
including academia and TEDx; she is an accomplished author who has
published numerous articles and books.
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