In the event that you encounter some unfamiliar terminology on our site or in any associated reports, we have prepared this glossary of medical terms.

ACTH (adrenocorticotrophic hormone):A hormone secreted by the anterior pituitary gland that acts primarily on the adrenal cortex, stimulating its growth and its secretion of corticosteroids. Its production is increased during times of stress.

Acoustic neuroma: A tumour of the auditoryc nerve.

Age-standardised: A rate which has been adjusted to minimise the effects of differences in age composition when comparing rates for different populations.

Alpha band: is the spectral component in the EEG signal, which falls between 8-13 Hz.

Aneuploidy: A genetically unbalanced condition in which a number of chromosomes for a organism that is not an exact multiple of the haploid number. e trisomy 21 is a form of aneuploidy.

Apoptosis: Programmed cell death.

Association: Statistical dependence between two outcomes.

Atopic dermatitis (AD): A pruritic disease of unknown origin that usually starts in early infancy and is typified by pruritus, eczematous lesions, xerosis (dry skin), and lichenification on the skin (thickening of the skin and increase in skin markings).

Autonomic nervous system: The portion of the nervous system concerned with regulation of the activity of cardiac muscle, smooth muscle, and glands. There are two main components, the sympathetic and the parasympathetic nervous systems.

Bcl-2 protein: Prototype for a family of mammalian genes and the proteins they produce. They govern mitochondrial outer membrane permeabilization (MOMP) and can be either pro-apoptotic or anti-apoptotic.

Bias: Deviation of results or inferences from the truth, or processes leading to such deviation.

Binucleated: Having two nuclei.

Biological effects: A range of possible consequences, depending on the type and degree of cellular damage that may result from exposure to an external agent.

Blood-brain barrier: The barrier that exists between the blood and the cerebrospinal fluid, which prevents the passage of various substances from the blood stream to the brain. It is built up by endothelial cells lining the cerebral capillaries.

Caenorhabditis elegans: A microscopic (~1 mm) nematode (roundworm) that normally lives in soil.

Carcinogenesis: The production of a malignant new growth.

Case control study: A study that starts with the identification of persons with the disease (or other outcome) of interest, and a suitable control group of persons without the disease.

Causal relationship: The relating of causes to the effects they produce. Most of epidemiology concerns causality and several types of causes can be distinguished. It should be clearly stated, however, that epidemiologic evidence by itself is insufficient to establish causality.

Cell cycle: The cycle of cell growth, replication of the genetic material and nuclear and cytoplasmic division.

Chromatid: One of the usually paired and parallel strands of a duplicated chromosome, joined by a single centromere.

Chromosomes: The self-replicating genetic structures of cells containing the cellular dna that bears in its nucleotide Sequence the linear array of genes.

Chromosome aberration: A deviation in the normal number of chromosomes or in their morphology.

Circadian: Pertaining to a period of about 24 hours; applied especially to the rhythmic repetition of certain phenomena in living organisms at about the same time each day (circadian rhythm).

Clustering: An aggregation of relatively uncommon events or diseases with well-defined distribution patterns, in relation to time or place or both.

Cochlea: Snail-shapes structure in the inner ear that contains the organ of hearing.

Cognitive: Pertaining to cognition - that operation of the mind by which we become aware of objects of thought or perception. It includes all aspects of perceiving, thinking, and remembering.

Cohort study: A study in which a population (i.e., a cohort) is defined according to the presence or absence of a factor that might influence the probability of occurrence of a given disease or other outcome. The cohort is then followed to determine if those exposed to the factor are indeed at greater risk of the outcome.

Comet assay: An uncomplicated and sensitive technique for the detection of DNA damage at the level of the individual cell.

Confidence interval: A range of values for a variable of interest e.g., a rate, constructed so that this range has a specified probability of including the true value of the variable e.g. the reference to Dolk et al. mentions "an excess risk of 1.83 (95% CI 1.22 ­ 2.74)". This means that the estimated risk is 1.83, and there is a 95% probability that the "true" risk (if that could be ascertained) is within the range 1.22 ­ 2.74.

Confounding: The distortion of an apparent effect of an exposure on risk, brought about by the association with other factors that can influence the outcome. For example, a study might suggest that alcohol intake is associated with a higher risk of heart disease, but this apparent relationship is seen because those who drink alcohol are also more inclined to smoke. When their smoking is taken into consideration, the relationship between alcohol intake and heart disease disappears.

Congenital: referring to conditions that are present at birth.

Control group: A sample in which a factor whose effect is being estimated is absent or is held constant, in order to provide a comparison.

Cortisol: The major natural glucocorticoid hormone synthesised in the adrenal cortex. It affects the metabolism of glucose, fats and protein, regulates the immune function, and has many other actvities.

Cross-sectional study: A study that examines the relationship between diseases and other factors, as they exist in a population at one particular time. The temporal sequence of cause and effect cannot necessarily be determined in this type of study.

Cytochemistry: The study of the locations, structural relationships, and interactions of cellular constituents.

Cytogenetics: A branch of biology that deals with the study of heredity and variation by the methods of both cytology and genetics. The cytological approach to genetics, mainly involving microscopic studies of chomosomes.

DNA: Deoxyribonucleic acid; it constitutes the primary genetic material of all cellular material and the DNA viruses, and occurs predominantly in the nucleus.

Dose-response relation: The relationship between the amount of exposure [Radiation) and the resulting changes in body function or health (response).

Double-blind trial: A procedure of blind assignment to study and control groups and blind assessment of outcome, designed to ensure that ascertainment of outcome is not biased by knowledge of the group to which an individual was assigned.

Ecological study: A study in which the units of analysis are populations or groups of people, rather than individuals.

Electroencephalogram (EEG): a tracing of electrical activity arising from brain function

Electromagnetic sensibility: The ability to perceive the electromagnetic field (EMF) without necessarily developing health symptoms attributed to EMF exposure.

Endothelial: Pertaining to the layer of cells that lines the cavities of the heart and of the blood and lymph vessels.

Enzyme: A protein molecule that catalyzes chemical reactions of other substances without itself being destroyed or altered upon completing the reactions.

Epidemiology: The study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to control of health problems.

Ethyl methanesulfonate (EMS): A mutagenic, teratogenic, and possibly carcinogenic organic compound with formula C3H8O3S.

Experimental study: A study in which conditions are under the direct control of the investigator.

Exposure: The amount of a factor to which a group or individual was exposed.

Exposure assessment: The process of measuring or estimating the intensity, frequency, and duration of human exposures to an agent (e.g. mobile phone radiofrequency field) currently present in the environment.

Fibroblast: Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.

Fibrosis: The formation of fibrous tissue as a reparative or reactive process.

Free radical: A compound that carries an unpaired electron; such radicals are extremely reactive, with a very short half-life.

FSH (follicle stimulating hormone): A hormone secreted by the anterior pituitary gland, which stimulates follicle production in the ovary and estrogen production, and promotes the changes in the uterus characteristic of the first portion of the menstrual cycle. In the male, it stimulates spermatogenesis.

Gene Expression: The full use of the information in a gene via transcription and translation leading to production of a protein and hence the appearance of the phenotype determined by that gene.

Genomics: A branch of biotechnology concerned with applying the techniques of genetics and molecular biology to the genetic mapping and DNA sequencing of sets of genes or the complete genomes of selected organisms using high-speed methods.

Genotoxic: Damaging to DNA.

Glial fibrillary acidic protein (GFAP): The degenerative brain condition called Alexander disease is caused by mutation in GFAP (glial fibrillary acidic protein). The GFAP gene provides instructions for making GFAP protein, a member of the intermediate filament family that provides support and strength to cells. Several molecules of GFAP protein bind together to form the main intermediate filament found in specialized brain cells called astrocytes.

GH (growth hormone): A hormone secreted by the anterior pituitary gland, which stimulates growth of the body. It also has an effect on the metabolism of fat, carbohydrate, and protein.

Glial (or neuroglial): The supporting structure of nervous tissue.

Glioma: Usually used as a term to include all primary intrinsic neoplasms of the brain and spinal cord.

Gliosis: A process leading to scars in the central nervous system that involves the production of a dense fibrous network of neuroglia (supporting cells) in areas of damage. Gliosis is a prominent feature of many diseases of the central nervous system, including multiple sclerosis and stroke. After a stroke, neurons die and disappear with replacement gliosis.

Healthy worker effect: Workers usually exhibit lower overall death rates than the general population, due to the fact that the severely ill and disabled are ordinarily excluded from employment. Death rates in the general population may be inappropriate for comparison if this effect is not taken into account.

Heat shock protein: Any of a group of proteins first identified as being synthesized in response to hyperthermia, hypoxia, or other stresses, and believed to enable cells to recover from these stresses, perhaps by enabling recovery of gene expression. Hsp70s are a family of ubiquitously expressed proteins. Proteins with similar structure exist in virtually all living organisms. The Hsp70s are an important part of the cell's machinery for protein folding, and help to protect cells from stress.

Hematopoietic: Pertaining to or effecting the formation of blood cells.

Hormone: A chemical substance produced in the body by an organ, which has a specific regulatory effect on the activity of other organs or cells.

Hippocampus: Area of gray matter extending the entire length of the floor of the temporal horn of the lateral ventricle of the brain.

Histology: That part of anatomy which deals with the minute structure, composition, and function of the tissues.

Hydrophilic: Readily absorbing moisture.

Immunocytochemistry: The application of immunochemical techniques (which use antibodies as chemical reagents) to cytochemistry.

Incidence: The number of instances of illness commencing, or death occurring, during a given period in a specified population.

In vitro: Observable in a test tube.

In vivo: Within the living body.

Ipsilateral: Located on or affecting the same side of the body. Opposite to contralateral.

Karyolysis: The destruction of a cells nucleus.

Karyorrhexis: Degeneration of the nucleus of a cell. There is contraction of the chromatin into small pieces, with obliteration of the nuclear boundary.

Knockout: informal term for the generation of a mutant organism in which the function of a particular gene has been completely eliminated (a null allele).

Latency: The period of subclinical disease following exposure that ends with the onset of disease.

Leukemia: A progressive, malignant disease of the blood-forming organs, characterised by distorted proliferation and development of leukocytes and their precursors in the blood and bone marrow.

Leukocyte: A white blood cell, specifically a colorless cell with a nucleus, found in blood and lymph. They can produce antibodies and move through the walls of vessels to migrate to sites of injury, where they isolate and destroy dead tissue, foreign protein and bacteria.

LH (luteinising hormone): A hormone secreted by the anterior pituitary gland, which with FSH promotes ovulation and promotes androgen and progesterone secretion. In the male it stimulates the development and functional activity of testicular Leydig cells. These cells produce male hormones, especially testosterone.

Lymphocyte: The white blood cell found in the blood, lymph, and lymphoid tissues, that are the body's immunologically competent cells and their precursors.

Lymphoma: Any neoplastic disorder of the lymphoid tissue.

Malignant: Malignant tumours have the ability to invade and destroy surrounding tissues and to spread to more distant parts of the body (metastasis). Opposition to benign.

Melatonin: a hormone synthesised by the pineal gland. It is implicated in the regulation of sleep, mood, puberty, and ovarian cycles.

Meningioma: A benign, slow-growing tumour of the meninges, usually next to the dura mater.

Meta-analysis: A statistical technique for amalgamating, summarising, and reviewing previous quantitative research.  By using meta-analysis, a wide variety of questions can be investigated, as long as a reasonable body of primary research studies exist.  Selected parts of the reported results of primary studies are entered into a database, and this "meta-data" is "meta-analyzed", in similar ways to working with other data - descriptively and then inferentially to test certain hypotheses.

Monocytes: a relatively large mononuclear leukocyte that normally constitutes 3 – 7 % of the leukocytes in the circulating blood, and is normally found in lymph nodes, spleen. Bone marrow, and loose connective tissue.

Metabolism: The sum of the processes by which a particular substance is handled in the living body.

Micronucleus: The smaller of two types of nuclei when more than one is present in a cell. Micronuclei are thought to indicate chromosomal damage.

Misclassification:Inaccuracies in how subjects are categorized by exposure or disease
status.

Mitotic: Pertaining to mitosis.

Microarray: Sets of miniaturized chemical reaction areas that may also be used to test DNA fragments, antibodies, or proteins, by using a chip having immobilized target and hybridising them with probed sample. the color we get from the chip after hybridisation is then scanned and the data is analysed by a soft ware to find the expression level.

Micronuclei: Chromosome fragments that are not incorporated into the nucleus at cell division.

Mortality ratio: Actual deaths in a specified time period divided by the expected number, usually multiplied by 100.

Multivariate analysis: A set of techniques used when the variation in several variables has to be studied simultaneously.

Mutagenic: Inducing genetic mutation.

Neoplasia: The formation of a new and abnormal growth.

Neuroglial (or glial): The supporting structure of nervous tissue.

Neuron(e): A nerve cell. The basic unit of the nervous system, specialized for the transmission of electrical impulses.

Neurotransmitter: Any of a group of substances, released by a presynaptic cell that, upon excitation, crosses the synapse to stimulate or inhibit the postsynaptic cell.

Neutrophil: a granulocyte that is the chief phagocytic white blood cell.

Neurotrophic factors: These substances are responsible for the growth and survival of neurons during development, and for maintaining adult neurons. Neurotrophic factors also are capable of making damaged neurons regrow their processes in a test tube and in animal models.

Observational study: An epidemiologic study in situations where nature is allowed to take its course; changes or differences in one characteristic are studied in relation to changes or differences in other(s), without the intervention of the investigator.

Occipital lobe: The part of the brain near to the occipital bone, at the back of the head.

Odds ratio: The ratio of two odds. It is used frequently in case control studies where it is the ratio of the odds in favour of getting disease, if exposed, to the odds in favour of getting disease if not exposed.

Oncogene: A gene capable under certain conditions of causing the initial and continuing conversion of normal cells into cancer cells.

Oncogenicity: The capacity to cause tumours.

Otoacoustic emissions: Low-intensity sounds produced by the inner ear that can be quickly measured with a sensitive microphone placed in the ear canal.

Oxidation: The act of oxidizing or being oxidized. Chemically it consists of the increase of positive charges on an atom or the loss of negative charges.

Oxygen radicals: A substituent group of chemical elements rich in oxygen but incapable of prolonged existence in a free state.

Parietal lobe: The part of brain near to the parietal bone.

Personal exposimeter: A dosimeter for assessing individual RF exposure in an urban environment in a free-living individual.

Physiological: Normal; not pathological; characteristic of the normal functioning or state of the body.

Pineal gland, or pineal body: A small, somewhat flattened, cone-shaped organ in the epithalamus of the brain. It is the site of synthesis of melatonin.

Pituitary gland: It is located at the base of the brain and is attached by a stalk to the hypothalamus, from which it receives an important nerve and blood supply. There are two lobes - the anterior, which secretes most of the hormones, and the posterior, which stores and releases neurohormones that it receives from the hypothalamus.

Placebo: An inert medication or procedure.

Precautionary principle: The principle is precautionary measures to anticipate, prevent or minimize the causes due to radiofrequency fields and mitigate its adverse effects. Where there are threats of serious or irreversible damage, lack of full scientific certainty should not be used as a reason for postponing such measures.

Prevalence: The number of instances of a given disease or other condition in a given population at a designated time.

Protein expression: A subcomponent of gene expression. It consists of the stages after DNA has been translated into amino acid chains, which are ultimately folded into proteins.

Proteomics: A branch of biotechnology concerned with applying the techniques of molecular biology, biochemistry, and genetics to analyzing the structure, function, and interactions of the proteins produced by the genes of a particular cell, tissue, or organism, including the organization of the information in databases.

Psychomotor: Of or relating to movement or muscular activity associated with mental processes.

Psychophysiology: The physiology of psychology, i.e. the basic processes underlying the functioning of the mind and mental processes.

Rate ratio: The ratio of two rates ­ in epidemiology, the ratio of the rate in the exposed population to the rate in the unexposed population.

Random errors: vary in a nonreproducible way around a limiting mean. These errors can be treated statistically by use of the laws of probability.

Real-time PCR: A method of simultaneous DNA quantification and amplification. DNA is specifically amplified by polymerase chain reaction (PCR). After each round of amplification, the DNA is quantified.

Relative risk: The ratio of the risk of disease or death among the exposed to the risk among the unexposed.

REM sleep (Rapid eye movement sleep): The period of sleep during which the brain waves are fast and of low voltage, and activities such as heart rate and respiration are irregular. This type of sleep is associated with dreaming, mild involuntary muscle jerks, and rapid eye movements. It usually occurs three to four times each night at intervals of 80 to 120 minutes, each occurrence lasting from 5 minutes to more than an hour. In an adult, about 20 percent of sleep is REM sleep.

Risk: The probability that an event will occur.

Risk perception: The significance assigned to risks by stakeholders. This perception is derived form the stakeholders= expressed needs, issues, and concerns.

Regression on Order Statistics (ROS):  An implementation of a Regression on Order Statistics (ROS) designed for multiply censored analytical chemistry data. The method assumes data contains zero to many left censored (less-than) values.

Selection bias: Error due to systematic difference in characteristics between those who are selected for study and those who are not.

Sham exposure: A control group used to simulate the same environmental conditions of exposed samples, but in absence of radiation.

Statistical significance: Statistical methods allow an estimate to be made of the probability of the observed or greater degree of association between factors. From this estimate, in a sample of given size, the statistical "significance" of a result can be stated. A number that expresses the probability that the result of a given experiment or study could not have occurred purely by chance.

Subjective outcomes: Outcomes or symptoms that are difficult to quantify objectively (e.g., pain, headaches, sleep disturbances).

Synapse: The functional membrane-to-membrane contact of the nerve cell with another nerve cell.

Synergize: two or more agents or forces interacting so that their combined effect is greater
than the sum of their individual effects. Antagonize: two or more agents or forces interacting
so that one agent counteracts the effect of another agent. Potentiate: one agent promotes or
strengthens a biochemical or physiological action or effect of another agent.

Temporal relationship: In epidemiology, the timing of the relationship between a factor and an outcome. It is one of the criteria used to assign causality to a relationship.

Teratology: The division of embryology and pathology that deals with abnormal development and congenital anomalies.

Trophoblasts: Cells forming the outer layer of a blastocyst, which provide nutrients to the embryo and develop into a large part of the placenta. They are formed during the first stage of pregnancy and are the first cells to differentiate from the fertilized egg.

Tinnitus: Ringing of the ears.

TSH (thyroid-stimulating hormone): A hormone secreted by the anterior pituitary gland that promotes the growth of, sustains, and stimulates the hormonal secretion of the thyroid gland.

Tumourigenic: Capable of causing tumours. Can refer either to a carcinogenic substance or agent such as radiation that affects cells or to transformed cells themselves.

Tumor laterality: The preference in location of tumor in one portion of the body over other locations in the body.

Uveal melanoma: Cancer of the eye.

Vestibule of the ear: The cavity of the inner ear.

Vestibular system (balance system): The sensory system that provides the dominant input about movement and equilibrioception.

Sources:
Merriam-Webster's Collegiate Dictionary. www.m-w.com/cgi-bin/dictionary

Mosby's Medical, Nursing, and Allied Health Dictionary (1994). Mosby-Year Book Inc., St Louis, Missouri.

Last JM (1988). A dictionary of epidemiology. Oxford University Press Inc., New York.

Dorland's Illustrated Medical Dictionary (1994, 2003). WB Saunders Coy., Philadelphia.