Hyperactive airway

Persons who suffer from hepatic or renal insufficiency can become susceptible to ammonia toxicity. Toxicity from ammonia in these cases, however, results from endogenously produced ammonia. The limited systemic absorption of ammonia following inhalation exposure would be insignificant when compared with concentrations produced within the body (WHO 1986). Persons with hyperactive airway disease or other conditions that alter airway function (colds, cough, nasal congestion) are expected to be more susceptible to irritant effects of ammonia. 

Sulfur dioxide is irritating to the eyes, mucous membranes, and respiratory tract. High levels of exposure produce cardiac arrest. Moderate exposure produces pulmonary edema. Low exposure results in systemic acidosis. Individuals who have hyperactive airway disease, including asthma, may be particularly sensitive. 

SUR2B/Kir6.2 Efforts have also focused on the development of selective KAXP channel openers for vascular and nonvascular indications including angina, airway hyperactivity, bladder overactivity, and erectile... 

Asthma is a complex respiratory disorder that involves mast cell degranulation, mucous secretions, and smooth muscle hypertrophy and hyperresponsiveness. Smooth muscle hyperresponsiveness has suggested some defect in the regulation of smooth muscle contractility. Therefore, a number of studies concerning asthma have centered on whether alterations in the regulation of smooth muscle contraction (Figure 4) are responsible for hyperactivity in asthmatic airway smooth muscle. 

Cui ZH, Joetham M, Aydintug MK, Hahn YS, et al. 2003. Reversal of allergic airway hyperactivity after long term allergen challenge depends on (gamma) (delta) T cells. Am J Respir Crit Care Med. 168 1324-1332. 

Airflow obstruction in asthma is due to bronchoconstriction resulting from contraction of bronchial smooth muscle, inflammation of the bronchial wall, and increased mucous secretion. Asthmatic attacks may be related to recent exposure to allergens, inhaled irritants leading to bronchial hyperactivity and inflammation of the airway mucosa. The symptoms of asthma may be effectively treated by several drugs, but none of the agents provide a cure for this obstructive lung disease. 

The Navy should be aware that the altered atmospheric conditions on a disabled submarine would affect the toxicity of the gases. For example, cold temperatures will cause crew members to shiver this will increase the rate of respiration because of an increase in metabolic rate. Lower air temperature might also result in the crew s breathing unconditioned air, which is a risk factor for lowerairway disease and airway hyperactivity. However, data are lacking on the precise magnitude of effects therefore, the Navy should conduct research to determine the nature and magnitude of the effects from altered submarine atmospheric conditions. 

Asthma is a chronic inflammation disorder of the airways that make the bronchial tubes swell and narrow, producing wheezing, chest tightness, breathlessness, and coughing symptoms. Airway narrowing in asthma is caused by inflammation, bronchospasm, and bronchial hyperactivity. Asthma does not affect the alveoli and is reversible spontaneously and by drug treatment. Asthma is fully reversible and thus is different from COPD and emphysema, which are accompanied by destruction of alveolar walls and are irreversible. 

RADS is a type of asthma that develops after exposure to a single environmental or occupational exposure to a high concentration of a single chemical or chemical mixture. Though RADS clinically simulates bronchial asthma and is associated with airways hyperactivity, it is different from OA because of its rapid onset following a single exposure, its lack of a sensitization period requirement, and its occurrence without an allergic... 

Klink KJ, Meade BJ. Dermal exposure to 3 amino 5 mercapto 1,2,4 triazole (AMT) induces sensitization and airway hyperactivity in BAFB/c mice. ToxicolSci2003 75(l) 89-98. 

Howell MD, Weissman DN, Meade BJ. Latex sensitization by dermal exposure can lead to airway hyperactivity. Int Arch Allergy Immunol 2002 128(3) 201—11. 

Inflammatory disease associated with bronchial hyperactivity (BHR), bronchospasm, T mucus secretion, edema, and cellular infiltration. Early asthmatic responses (EAR) lasting from 30 to 60 min are associated with bronchospasm from the actions of released histamine and leukotrienes late asthmatic responses (LAR) involve infiltration of eosinophils and lymphocytes into airways - > bronchoconstriction and inflammation with mucus plugging. 

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