O-PYROCATECHUIC ACID 2,3-DiHydroxy Benzoic Acid
OCCUPATIONAL EXPOSURE LIMIT (OEL) the acceptable amount of the compound allowed in the air of a working area for high potency pharma. active ingredients


Histoplasmosis is caused by a fungus commonly found in the dust and soil of the Mississippi-Ohio River Valley region. Approximately 62% of the adult population living in this region are carriers. It affects men and women equally.

Histoplasmosis is contracted by inhaling dust that carries the fungal spores. Its effect on the body can vary widely in severity from one person to another. Many carriers have no symptoms at all, but those with mild exposure may experience flu-like symptoms and mild respiratory infections. Histoplasmosis is more likely to become a serious problem in people who already have a weakened immune system.

The fungus may affect the eye by causing small areas of inflammation and scarring of the retina. These are called “histo spots” and may be found in both eyes. Their affect on vision depends on the location of the scars. Scarring in the peripheral area of the retina may have little or no impact on vision, while a central scar affecting the macula may cause a prominent blind spot.

Most people with histo spots in the retina are totally unaware of their presence unless the central vision is affected. Studies indicate that only about 5% of those with histo spots are at risk of losing vision. Scientists have been unable find a link between the patients with minor histo spots and those who develop a severe loss of their central vision.

OCULT AMD (Ophthalmology) CNV caused by wet age-related macular degeneration (AMD) appears as two types of lesions: classic or occult. These terms are used to describe different patterns of CNV leakage as seen on fluorescein angiography. Classic CNV progresses more rapidly than occult, is more aggressive and easier to diagnose because the vessels are well defined and therefore easier to detect. As well, loss of sight occurs more rapidly with classic CNV. Occult CNV is less predictable and because the leakage is less obvious, more difficult to diagnose. While it is common for patients to develop both types of lesions, roughly half of all patients with occult CNV will develop classic CNV within a year
OFF LABEL PRESCRIBING Option, where physician can prescribe a drug that's been approved by FDA for one condition to treat a DIFFERENT condition
OIL SAND Alberta's deposits of bitumen: thick oil that must be mined or extracted with heat and converted into synthetic crude oil. Unquestionably, the sands have enough hydrocarbons to support a petrochemical industry
OLEFIN METATHESIS Is a chain reaction, but it can be imagined as a joining together of 2 olefins, which then split apart to form 2 different olefins. For example, 2 molecules of propene metathesize to one molecule of ethylene & one of 2-butene
OMEGA-3 FATTY ACID A class of fatty acids that have a double bond three carbons from the methyl moiety; reportedly, they play a role in lowering cholesterol and LDL levels
OMEGA-6 FATTY ACID a polyunsaturated fatty acid whose carbon chain has its first double valence bond six carbons from the beginning
OMNIDIRECTIONAL MIRRORS reflect light coming from all angles and polarizations. They can be constructed from multiple layers of transparent, nonconducting materials with very different indexes of refraction. Such mirrors are typically fragile, however, and restricted to planar geometries
ONCOLOGY Branch of Medicine dealing with Diag.; Etiology; Prevn.; Prognosis & Therapy of Cancers & Neoplasias
OPEN READING FRAME Coding part of an individual gene sequence. Segment in mRNA that contains codons that can be translated into an amino acid seq & that does not contain a termination codon
OPERON Genes that are cotranscribed
OPIOID BOWEL DYSFUNCTION severe constipation experienced by patients taking traditional opioid narcotics for chronic pain relief.
OPTICAL ENCODER A linear or angular position feedback device using light fringes to develop position information
OPTICAL RECORDING In computing, sound reproduction, and video, an optical disc is a flat, generally circular disc which can contain data encoded in microscopic pits
OPTOELECTRONICS as processing light for conversion into electronic signals and vice versa. Thus, the term covers applications ranging from compact disc players to electronic displays. But the area of growing interest to chemical companies is in optical telecommunications components, sometimes called photonics.
ORAL BIOAVAILABILITY the degree to which it becomes systemically available when taken by mouth
ORAL MUCOSITIS (Oncology) Oral mucositis is a common, debilitating side effect of cancer treatment occurring in approximately 40 percent of patients receiving chemotherapy and radiation. Oral mucositis is inflammation of the moist tissue lining the mouth and ranges from redness to severe ulceration. Symptoms of mucositis vary from pain and discomfort to an inability to take food or fluids. Mucositis may also limit a patient's ability to tolerate either chemotherapy or radiation, and may be so severe as to delay treatment, limiting the effectiveness of the cancer therapy. Patients with damage to the lining of the mouth and a reduced immunity resulting from chemotherapy and radiation are also prone to opportunistic mouth infections. The use of morphine or other narcotic analgesics are indicated when severe pain accompanies the mucositis
ORANGE BOOK [U.S.A. (FDA)] Lists all drug products approved by FDA on the basis of safety & effective
ness. The book also contains therapeutic equivalence evaluations for approved multisource drugs. These evaluations, FDA says, are to serve as public information & advice in prodt selection, as between generic & branded sources, & in helping to decrease drug R&D & health care costs. An addendum contains related exclusivity - as under the Orphan Drug Act, which gives 7 years of marketing exclusivity to drugs developed for rare diseases - & patent information
Once a patent is listed, a Co seeking to market a generic version is required to file a certification with FDA explaining whether it considers the patent valid or whether its generic prodt will infringe the patent. The patent holder then has 45 days to respond, as with an infringement lawsuit. Filing such a suit causes FDA to step aside & refrain from granting final approval for the generic prodt for 30 months, regardless of the merits of the lawsuit, or less if the case is decided in the generic firm's favor, if the generic firm gets an injunction on the listing.is the common name of "Approved Drug Products with Therapeutic Equivalence Evaluations," the FDA publication that lists, among others, patents protecting the active ingredient, formulation, and method of use of a drug product
ORGANIC SUNSCREEN They work by absorbing UV light & dissipating it as heat. Examples

- Avobenzone
- 4-MethylBenzylidene Camphor
- Homosalate
- Octyl MethoxyCinnamate
- Oxybenzone
ORPHAN DRUGS those with a treatment population of less than 200,000 patients
ORTHOKERATOLOGY refractive errors in eye
ORTHOSTATIC HYPOTENSION decrease of at least 20 mm Hg in systolic blood pressure when an individual moves from a supine position to a standing position. Nonneurogenic causes of orthostatic hypotension are related to cardiac pump failure, reduced intravascular volume, venous pooling or a medication side effect. Neurogenic causes include both central and peripheral nervous system lesions. The diagnostic evaluation requires a systematic review of medications and coexisting medical conditions along with a neurologic examination to search for treatable factors that may be contributing to orthostatic hypotension. Specific testing of autonomic function is useful for detecting subclinical orthostatic hypotension or for monitoring autonomic function over a period of time. Treatment is directed at improving the patient's symptoms rather than achieving arbitrary blood pressure goals.
OSMOLALITY The concentration of osmotically active particles in solution expressed in terms of osmoles of solute per kilogram of solvent. The osmolality is directly proportional to the colligative properties of solutions, osmotic pressure, boiling point elevation, freezing point depression and vapour pressure lowering
OSTEOARTHRITIS Osteoarthritis is primarily a noninflammatory disorder of movable joints characterized by an imbalance between the synthesis and degradation of the articular cartilage, leading to the classic pathologic changes of wearing away and destruction of cartilage.
Osteoarthritis (OA) is one of the oldest and most common diseases in humans and the most common form of joint disease in the world.

The term "osteoarthritis" means "joint inflammation." Because OA does not present clinically as an inflammatory disorder, some have suggested that the term "osteoarthrosis," or "joint disease," is more appropriate. Although OA is considered a noninflammatory form of arthritis, there can be a small inflammatory component. However, this inflammation is much less intense than that seen in rheumatoid arthritis, which is considered an inflammatory form of arthritis.

In some respects, OA appears to be a normal response of the joint to cartilage wear. OA was once thought to occur when the joints were just "worn out." Consequently, the phrase "wear and tear" may be used to describe OA, and it is sometimes referred to as degenerative joint disease. Some researchers no longer use the term "wear and tear" arthritis as a synonym for OA as newer information regarding the pathogenesis of OA has become available.

Although the etiology of OA remains elusive, the imbalance between the synthesis and degradation of the articular cartilage results in increased deterioration or breakdown of the cartilage and the formation of new bone at the joint surfaces and margins. This breakdown of joint cartilage often results in joint pain and loss of mobility, which may lead to long-term disability. This is of major concern because the prevalence of OA is expected to increase significantly due to the aging of the U.S. population.

OSTEOCHONDRITIS DISSECANS A type of osteochondritis in which articular cartilage and associated bone becomes partially or totally detached to form joint loose bodies. Affects mainly the knee, ankle, and elbow joints
OSTEOCLAST Cells that degrade bone
OSTEOGENESIS IMPERFECTA is a group of genetic diseases in which the bones are formed improperly, making them fragile and prone to breaking.
OSTEOMYELITIS a bone infection secondary to diabetic foot ulcers
OTBAF 9,9-Bis(3-Me-4-aminophenyl)fluorene
OVERHAUSER EFFECT (medical diag. MRI) In which an esr transition in an administere
d paramagnetic species (OMRI contrast agent) is coupled to the nuclear spin system of the imaging nuclei. The OVERHAUSER effect (also known as dynamic nuclear POLARISATION) can increase population difference between excited & ground nuclear spin states of selected nuclei & thereby amplify the MR signal intensity by factor of > 100 allowing OMRI images to be generated rapidly & with rel. low primary magnetic fields. Most of OMRI contrast agents disclosed to date (12.00) are radicals which are used to effect polarisation of imaging nuclei in vivo
OXALOBACTER FORMIGENES is an oxalate-degrading anaerobic bacterium which colonizes the large intestine in humans. While the human colon is normally cultivated by these bacteria, they can be lost due to antibiotic treatment with quinolones (though not penicillin or Bactrim). In people lacking the bacterium, calcium oxalate is not degraded in the intestinal tract and stones can recur
OXIDATIVE STRESS A disturbance in the prooxidant-antioxidant balance in favor of the prooxidant, leading to potential damage
OXYTOCIC A natural or synthetic hormone which causes contraction of the uterine muscle