N

N Glycosylation See GLYCOSYLATION.

n-3 Fatty Acids Also known as “omega-3” fatty acids. Research indicates there are human health benefits (e.g., antithrombotic, reduce/avoid coronary heart disease) if the ratio of n-6 to n-3 fatty acids contained in the diet is higher than 3, but less than 10. Soybean oil has an n-6/n-3 ratio of approximately 7:1. Examples of n-3 fatty acids include linolenic acid (C18:3n-3). Research indicates that human consumption of n-3 fatty acid(s) imparts anti-thrombotic and anti-inflammatory health benefits; plus it lowers levels of triglycerides content in the bloodstream. During 2000, research was published that indicated a 66% reduction in probability for children to develop juvenile (Type I) diabetes, if their mothers consumed significant quantities of n-3 fatty acids during pregnancy. See also POLYUNSATURATED

FATTY ACIDS (PUFA), DOCOSAHEXANOIC ACID

(DHA), EICOSAPENTANOIC ACID (EPA), LINOLENIC

A C I D , S O Y B E A N O I L , T H R O M B O S I S , T R I - GLYCERIDES, CORONARY HEART DISEASE (CHD),

DIABETES, INSULIN.

n-6 Fatty Acids Also known as “omega-6” fatty acids. Research indicates there are human health benefits (e.g., antithrombotic, reduce/avoid coronary heart disease) if the ratio of n-6 to n-3 fatty acids contained in the diet is higher than 3 but less than 10. Soybean oil has an n-6/n-3 ratio of approximately 7:1. Examples of n-6 fatty acids include linoleic acid (C18:2n-6). Research indicates that consumption of n-6 fatty acids has been related to decreased cholesterol levels in the bloodstream, and decreased incidence of coronary heart disease (CHD).

See also POLYUNSATURATED FATTY ACIDS (PUFA),

ARACHIDONIC ACID, LINOLEIC ACID, SOYBEAN OIL,

0-8493-XXXX-X/01/$0.00+$1.50 © 2001 by CRC Press LLC

THROMBOSIS, CORONARY HEART DISEASE (CHD),

CHOLESTEROL.

NAD (NADH, NADP, NADPH) N i c o t i n a - mide-adenine dinucleotide, also known as diphosphopyridine nucleotide, codehydrogenase 1, coenzyme 1, and coenzymase by its d i s c o v e r e r s , H a r d e n a n d Yo u n g . C21H27O14N7 P2. An organic coenzyme (molecule) that functions as a distinct yet integral part of certain enzymes. NAD plays a role in certain enzymes concerned with oxidation/reduction reactions. Meanings: NADH, nicotinamide-adenine dinucleotide, reduced; NADP, nicotinamide-adenine dinucleotide phosphate; and NADPH, nicotinamide-ade- nine dinucleotide phosphate, reduced. See

also ENZYME, COENZYME, OXIDATION-REDUCTION
REACTION, NITRIC OXIDE SYNTHASE.
NADA (New Animal Drug Application) A n	N
application to the U.S. Food and Drug
Administration (FDA) to begin testing/studies
of a new drug for animals (e.g., livestock),
that might (eventually) lead to its FDA
approval. See also IND.
NADH N i c o t i n e - a d e n i n e d i n u c l e o t i d e ,
reduced. See also NAD.
NADP Nicotine-adenine dinucleotide phos-
phate. See also NAD, NITRIC OXIDE SYNTHASE.
NADPH Nicotinamide-adenine dinucleotide
phosphate, reduced. See also NAD.
Naked DNA See NAKED GENE.
Naked Gene A bare gene (strand of DNA that
codes for a protein) that has been extracted
from an organism, or otherwise derived (e.g.,
synthesized from sequence data). During the
1990s, it was discovered that:
• Injecting the Duchenne Muscular Dys-
trophy “naked gene” into muscle tissue
in the bodies of people suffering from

© 2002 by CRC Press LLC

		Muscular Dystrophy (MD) resulted in
		temporary production of the relevant
		protein in that muscle tissue (i.e., tem-
		porary MD symptom reduction).
	•	Injecting the VEGF “naked gene” into
		relevant tissue in the bodies of people
		suffering from inadequate local blood
		supply (the shortage of blood flow to
		heart known as myocardial ischemia,
		lack of blood flow in legs or other
		extremities, etc.) resulted in (new)
		growth of blood vessels/endothelium,
		and reduction in symptoms of those
		inadequate blood-supply conditions.
	•	Injecting the “naked gene” for the rele-
		vant antigen of certain pathogens into
		some tissues in the (usual disease host)
		organism sometimes resulted in those
		(host organism) tissues taking up the
		“naked gene” and expressing some of
		the (pathogen’s) antigen(s), such that
		the (putative host organism’s) immune
		system initiates an immune response
		(thereby resulting in vaccination against
		the disease conferred by the pathogen).
		When that happens, such “naked genes”
N
		are referred to as “DNA vaccines.”

See also GENE, DEOXYRIBONUCLEIC ACID (DNA),

PROTEIN, ORGANISM, SYNTHESIZING (OF DNA

MOLECULES), SEQUENCING (OF DNA MOLECULES),

DUCHENNE MUSCULAR DYSTROPHY GENE, MUSCU-

LAR DYSTROPHY (MD), VASCULAR ENDOTHELIAL

GROWTH FACTOR (VEGF), PATHOGEN, EXPRESS,

DNA VACCINES, IMMUNE RESPONSE, CELLULAR

IMMUNE RESPONSE, HUMORAL IMMUNITY, ANTI-

BODY, DNA VECTOR.

Nanobiology See NANOTECHNOLOGY, NANOCOM-

POSITES, BIOINORGANIC, NANOCRYSTALS, NANO-

ELECTROMECHANICAL SYSTEM (NEMS).

Nanobots Refers to very small “robots” whose dimensions could be measured in terms of nanometers (nm), and could perform specific

tasks. See also NANOELECTROMECHANICAL SYSTEM (NEMS), NANOSCIENCE, MEMS (NANOTECH- N O L O G Y ), B I O M E M S , N A N O M E T E R S (N M ),

NANOTECHNOLOGY.

Nanocomposites Nanometer-scale composite structures composed of organic molecules intimately incorporated with inorganic molecules. For example, abalone shellfish make

mother-of-pearl shells via an intimate combination of protein and calcium carbonate. Researchers are working on making semiconductor devices (chips) containing peptides and other organic molecules attached to silicon or gallium arsenide. They are also working on nanoelectromechanical systems (NEMS) that would have tiny “moving parts” to be able to do “work” at nanometer

scale. See also NANOMETERS (NM), NANOTECHNOLOGY, PROTEIN, BIOCHIP, PEPTIDE, BIOSENSORS

(ELECTRONIC), BIOINORGANIC, NANOELECTROME-

CHANICAL SYSTEM (NEMS).

Nanocrystal Molecules Coined by researchers A. Paul Alivisatos and Peter G. Schultz, it is a term used to describe double-stranded DNA molecules that have several multiatom clusters of gold attached to them. As of 1996, these researchers were working to try to create nanometer-scale electrical circuits, semiconductors, etc. A separate methodology, researched by Chad A. Mirkin et al., utilizes strands of DNA to reversibly assemble gold nanoparticles (nanometerscale multi-atom particles) into supramolecular (many molecule) agglomerations, in which the gold particles are separated from each other by a distance of approximately 60 Angstroms. The aggregation of these DNA-metal nanoparticles causes a visible color change.

As of 1996, these researchers were working to try to create simple and rapid tests that would indicate the presence of a virus (e.g., HIV-1 or HIV- 2) via a visible color change. Such a test would use two noncomplementary DNA sequences, each of which has attached to it a gold nanoparticle (via a thiol group). The two sequences would be selected for their ability to latch onto a target sequence in the desired virus, but they would be unable to combine with each other, since they are noncomplementary. When doublestranded DNA molecules possessing two “sticky ends” (that are complementary to the sequences attached to virus) are added, the resultant color change indicates virus pres-

ence. See also DOUBLE HELIX, DEOXYRIBONUCLEIC ACID (DNA), ANGSTROM (Å), NANOMETERS (nm), HYBRIDIZATION SURFACES, BASE PAIR (bp),

SELF-ASSEMBLY, NANOTECHNOLOGY, STICKY ENDS,

© 2002 by CRC Press LLC

	H Y B R I D I Z A T I O N (M O L E C U L A R G E N E T I C S ),	the protein alpha-hemolysin. Because a
	SEQUENCE (OF A DNA MOLECULE), VIRUS, BIO-	DNA molecule moving through such a nan-
	SENSORS (CHEMICAL), BIOCHIP, MICROFLUIDICS,	opore temporarily blocks the nanopore (until
	NANOCRYSTALS.	it dissociates into a single DNA strand and
	Nanocrystals A term used to refer to any crys-	“slides” through), an electrical current/volt-
	talline structure possessing dimensions (e.g.,	age applied to that nanopore varies (in
	overall width) measured in terms of nanom-	amplitude, modulation, duration, etc.) as the
	eters. See also NANOMETERS (NM), QUANTUM	DNA strand “slides through,” in a way that
	DOT, NANOSCIENCE, NANOTECHNOLOGY, NANOC-	provides information (e.g., to scientist)
	RYSTAL MOLECULES, NANOCOMPOSITES.	about the nucleotides that makeup that DNA
	Nanoelectromechanical System (NEMS)	strand. It is expected that nanopores will also
	Refers to working (i.e., those with moving	be used for DNA sequencing. See also NANO-
	“mechanical parts”) systems of a scale	SCIENCE, NANOMETERS (NM), NANOTECHNOLOGY,
	whose relevant dimensions are measured in	PLASMA MEMBRANE, MICELLE, DEOXYRIBO-
	terms of nanometers (nm). For example, in	NUCLEIC ACID (DNA), NUCLEOTIDE, SINGLE-
	2000, Carlo Montemagno and colleagues	NUCLEOTIDE POLYMORPHISM (SNP), ION CHAN-
	assembled a NEMS in which a tiny metal	NELS, SEQUENCING (OF DNA MOLECULES).
	“propeller” was caused to spin within the	Nanoscience A term utilized to refer to the
	domain of the enzyme ATP Synthase. The	science underlying nanotechnology, nano-
	metal propeller was attached (via a biotin-	crystals, nanocrystal molecules, nanocompos-
	streptavidin “molecular linkage”) to the one	ites, “quantum dots,” nanoelectromechanical
	subunit (designated alpha) of ATP Synthase	systems (NEMS), etc. “Nanoscale” materi-
	that rotates within the other (hollow) part of	als (i.e., those whose dimensions are approx-
	ATP Synthase molecule when ATP is “fed”	imately 1 to 100 nanometers) generally
	to a free standing (i.e., not in cell) molecule	possess different chemical and physical
	of ATP Synthase. See also NANOMETERS (NM),	properties than “bulk” materials. For exam-
			N
	ATP SYNTHASE, ENZYME, ADENOSINE TRIPHOS-	ple, when bulk gold metal is formed into
	PHATE (ATP), BIOTIN, AVIDIN, NANOCOMPOSITES,	nanoscale rods, the intensity of its fluores-
	NANOSCIENCE, MICROMACHINING.	cence increases by a factor of approximately
	Nanofluidics See MICROFLUIDICS.	10 million. Another example is that silicon
	Nanogram (ng) 10–9 gram, or 3.527 × 10–11	nanocrystals (i.e., quantum dots) dispersed
	ounce (avoirdupoir).	in a silicon dioxide matrix, emit larger-than-
	Nanometers (nm) 10–9 meter. Often used to	typical-for-silicon amounts of light, when
	express wavelengths of light (e.g., in a spec-	stimulated (i.e., bombarded) with pulses of
	trophotometer), or to express dimensions of	ultraviolet light. See also NANOTECHNOLOGY,
	nanocomposites, devices (e.g., of miniature	NANOCRYSTALS, QUANTUM DOT, NANOCRYSTAL
	“machines” called nanoelectromechanical	MOLECULES, NANOCOMPOSITES, NANOELECTRO-
	systems), etc. in the field of nanotechnology.	MECHANICAL SYSTEM (NEMS), SELF-ASSEMBLY
	See also SPECTROPHOTOMETER, NANOTECHNOL-	(OF A LARGE MOLECULAR STRUCTURE), NANOPORE,
	OGY, NANOCOMPOSITES, NANOELECTROMECHANI-	MICROFLUIDICS.
	CAL SYSTEM (NEMS), MICROFLUIDICS, METER.	Nanotechnology From the Latin nanus, dwarf,
	Nanoparticles See NANOCRYSTALS, NANOCRYS-	so it literally means “dwarf technology.” The
	TAL MOLECULES, NANOTECHNOLOGY.	word was originally coined by Norio Tan-
	Nanopore A device that can distinguish	iguchi in 1974, to refer to high precision
	between DNA strands (molecules) that differ	machining. However, Richard Feynman and
	from each other by a single nucleotide (in	K. Eric Drexler later popularized the concept
	the makeup of those molecular strands).	of nanotechnology as a new and developing
	Developed by David Deamer and Mark Ake-	technology in which man manipulates
	son in 2001, it consists of an artificial mem-	objects whose dimensions are approximately
	brane (lipid bilayer) with a “hole”	1 to 100 nanometers. Theoretically, it is pos-
	(nanopore) punctured in that membrane by	sible that in the future a variety of man-made

© 2002 by CRC Press LLC

“nano-assemblers” [tiny (molecular) machines smaller than a grain of sand] would manufacture those things that are produced today in factories. For example, enzyme molecules function essentially as jigs and machine tools to shape large molecules as they are formed in biochemical reactions. The technology also encompasses biochips, biosensors, and manipulating atoms and molecules in order to form (build) bigger, but still vanishingly small functional structures and machines. See also ENZYME,

GENOSENSORS, NANOMETERS (NM), BIOSENSORS

(ELECTRONIC), BIOCHIP, MICROFLUIDICS, NANO-

CRYSTALS, NANOCRYSTAL MOLECULES, BIOSENSORS

(CHEMICAL), QUANTUM DOT, NANOCOMPOSITES,

NANOELECTROMECHANICAL SYSTEM (NEMS),

SELF-ASSEMBLY (OF A LARGE MOLECULAR STRUC-

TURE), NANOPORE, BIOMEMS.

Nanotube See NANOSCIENCE, NANOTECHNOLOGY,

SELF-ASSEMBLY (OF A LARGE MOLECULAR

STRUCTURE).

Napole Gene See REDEMENT NAPOLE (RN) GENE.

NAS See NATIONAL ACADEMY OF SCIENCES.

National Academy of Sciences (NAS) A private, self-perpetuating society of distin- N g u i s h e d s c h o l a r s i n s c i e n t i fi c a n d engineering research, dedicated to the advancement of science and technology and their use for the general welfare. Under the authority of its congressional charter of 1863, the NAS has a working mandate that calls upon it to advise the U.S. Federal Government on scientific and technical matters.

See also VITAMIN E.

National Cancer Institute (NCI) One of the National Institutes of Health. See also

NATIONAL INSTITUTE OF HEALTH (NIH).

National Heart, Lung, and Blood Institute (NHLBI) One of the National Institutes of

Health. See also NATIONAL INSTITUTES OF HEALTH (NIH).

National Institute of Allergy and Infectious Diseases (NIAID) The main agency of the National Institutes of Health. See also

NATIONAL INSTITUTES OF HEALTH (NIH).

National Institute of General Medical Sciences (NIGMS) One of the National Institutes of Health. See also NATIONAL INSTITUTES

OF HEALTH (NIH).

National Institutes of Health (NIH) The major U.S. Government sponsor of biotechnology research. It is composed of a group of government institutes that each focus on specific medical areas. See also RECOMBINANT

DNA ADVISORY COMMITTEE (RAC).

Native Conformation The normal, biologically active conformation (i.e., the threedimensional arrangement of its atoms) of a protein molecule. See also CONFORMATION.

Naturaceuticals See NUTRACEUTICALS.

Natural Killer Cells These cells are involved in tumor surveillance. They also kill virusladen cells.

NCI See NATIONAL CANCER INSTITUTE (NCI).

NDA (to FDA) New Drug Application (to the U.S. Food and Drug Administration). A (paper) application to the U.S. Food and Drug Administration (FDA) seeking approval of a new drug that has undergone Phase 2 and Phase 3 clinical trials. An NDA is submitted in the form of (thousands of) pages of (clinical and other) data, along with various analyses (e.g., statistical) of that data for efficacy, safety, etc. See also CANDA, FOOD

AND DRUG ADMINISTRATION (FDA), MAA, NDA (TO

KOSEISHO), PHASE I CLINICAL TESTING.

NDA (to Koseisho) New drug application. It is the Japanese equivalent to a U.S. IND (investigational new drug) application; to the Koseisho, the Japanese equivalent of the U.S. Food and Drug Administration (FDA).

See also IND, KOSEISHO, FOOD AND DRUG ADMIN-

ISTRATION (FDA).

Near-Infrared Spectroscopy (NIR) Refers to analytical instruments which shine light (possessing wavelengths between that of visible light and infrared light spectrum) onto samples (e.g., kernels of grain) and measure the reflected or transmitted (near-infrared) light in order to quickly determine the amounts of protein, fat, moisture, lignans, etc. present in the sample. In certain samples, the near-infrared light causes cells (or specific molecules) to fluoresce (i.e., as light of very defined wavelength), which can subsequently be utilized for measurement/identification of compounds within the sample. NIR is also being developed for use in quantifying (e.g., amounts that are present within the sample) of immunoassays and detection

© 2002 by CRC Press LLC