Tag: non-infectious diseases

Cancer is a group of diseases involving abnormal and rapid cell growth with the potential to invade or spread to other parts of the body. Signs and symptoms include a lump, abnormal bleeding, prolonged cough, unexplained weight loss and a change in bowel movements. Many cancers can be prevented by not smoking, maintaining a healthy weight, not drinking too much alcohol, eating plenty of vegetables, fruits and whole grains, vaccination against certain infectious diseases.

The ability to maintain functional telomeres may be one mechanism that allows cancer cells to grow in vitro for decades. Telomerase activity is necessary to preserve many cancer types and is inactive in somatic cells, creating the possibility that telomerase inhibition could selectively repress cancer cell growth with minimal side effects. If a drug or mutation can inhibit telomerase in cancer cells, the telomeres of successive generations will progressively shorten, limiting tumor growth.

Transgenic models are genetically modified organisms in which the genome has been altered through random integration of gene sequences.

Cryobiology is the branch of biology that deals with effects of low temperatures on living things. Teratology is the branch of science which deals with the study of congenital abnormalities and abnormal physiological development. Molecular biology is the branch of biology which deals with the the structure and function of the essential macromolecules. The major application of molecular biology to prevention and early detection of cancer and other diseases by identification of certain genes. Gerontology is the branch of science which deals with the study of old age, the process of ageing and the problems of aged people.

A deletion mutation occurs when part of a DNA molecule is not copied during DNA replication. This uncopied part can be as small as single nucleotide or as much as an entire chromosome. The loss of this DNA during replication can lead to genetic disease.

One of the hallmarks of human cancers is the intrinsic or acquired resistance to apoptosis. Evasion of apoptosis may contribute to carcinogenesis, tumor progression and also to treatment resistance, since most current anticancer therapies including chemotherapy, radio- and immunotherapy primarily act by activating cell death pathways including apoptosis in cancer cells.

HeLa  is an immortal cell line used in scientific research. It is the oldest and most commonly used human cell line. The line was derived from cervical cancer cells taken on February 8, 1951 from Henrietta Lacks, a patient who died of cancer on October 4, 1951. The cell line was found to be remarkably durable and prolific which warrants its extensive use in scientific research. The cells from Lacks's cancerous cervical tumor were taken without her knowledge or consent. Cell biologist George Otto Gey found that they could be kept alive, and isolated one specific cell, multiplied it, and developed a cell line. (Before this, cells cultured from other human cells would only survive for a few days; scientists spent more time trying to keep the cells alive than performing actual research on them. Cells from Lacks's tumor behaved differently.) As was custom for Gey's lab assistant, she labeled the culture 'HeLa', the first two letters of the patient's first and last name; this became the name of the cell line. These were the first human cells grown in a lab that were naturally "immortal", meaning that they do not die after a set number of cell divisions (i.e. cellular senescence). These cells could be used for conducting a multitude of medical experiments—if the cells died, they could simply be discarded and the experiment attempted again on fresh cells from the culture. This represented an enormous boon to medical and biological research, as previously stocks of living cells were limited and took significant effort to culture.