Membranous bronchioles

Mixed pattern Cellular bronchiolitis Bronchiolitis with inflammatory polyps, cicatricial bronchiolitis Respiratory and membranous bronchioles... 

In studies on hamsters and guinea pigs exposed to aerosols of crude and refined extracts from cotton mill trash and CMD, Kilburn et al (59) has further demonstrated recruitment of PMN beneath the basement membrane and on luminal surfaces of intrapulmonary airways and tracheas. When administered as aerosols or dust, polyphenolic extracts from cotton trash and pure and oxidization-polymerization products of quercetin also recruit PMN from the trachea to terminal bronchioles in hamsters (60). 

Fig. 3.1 Schematic diagram of the human respiratory system. The gross anatomy of the lung, the covering membranes (pleura), airways and air sacs (alveoli) are shown. The average diameter of portions of the air flow system are indicated trachea, 20 mm bronchus, 8 mm terminal and respiratory bronchioles, 0.5 mnn alveolar duct, 0.2 mm alveolar sacs, 0.3 mm.

Greenwalt, D. E., Johnson, V. G. and Mather, I. H. 1985B. Specific antibodies to PAS-IV, a glycoprotein of bovine milk-fat-globule membrane, bind to a similar protein in cardiac endothelial cells and epithelial cells of lung bronchioles. Biochem J. 228, 233-240. 

Epinephrine stimulates me beta-adrenergic receptors in me bronchioles, which in turn activate membrane-bound adenylate cyclase to synthesize more cyclic AMP, whereas theophylline inhibits the activity of phosphodiesterase, conserving the previously synthesized cyclic AMP. 

The lung. The middle diagram is a close-up view of the end of a bronchiole. Each bronchiole terminates in many alveolar sacs. The diagram on the right is a close-up view of an alveolus. The cell membrane of each alveolus is very thin and surrounded by many blood capillaries, thereby allowing for rapid exchange of oxygen for carbon dioxide, as well as absorption of other substances. 

When a substance is inhaled, it is exposed to membranes of the mouth or nose, pharynx, trachea, bronchi, bronchioles, alveolar sacs, and alveoli (Fig. 1). The lung has a potential absorption surface of some 70 m, a much larger surface than the small intestine. However, the lungs and their associated airways are... 

Acebutolol is a beta-adrenoceptor antagonist with membrane-stabilizing activity that is sometimes cited as being cardioselective but has considerable effects on bronchioles and peripheral blood vessels. 

Beta-blockers are one of the antihypertensive agents useful in patients with CAD because they have been shown to reduce morbidity and mortality. Beta-blockers competitively block both p, and P2 but with different selectivity. Blocking P, receptors, which are found primarily on cardiac muscle, will lead to negative chronotropic and inotropic effects. In hypertensive patients, this will lower their blood pressure. P2 receptors are found predominantly on the outer membrane of the smooth muscle cells of the vasculature, bronchioles, and myometrium and regulate the relaxation of these cells. Blockage of this receptor can lead to vasoconstriction and bronchoconstriction. 

The respiratory tract is divided into the upper and lower tracts. The upper respiratory tract contains the nares, nasal cavity, pharynx, and larynx and the lower tract consists of the trachea, bronchi, bronchioles, alveoli, and alveolar-capillary membrane. 

Paraquat, a herbicide that is highly toxic to humans, causes respiratory distress that can lead to death. Damage to membranes of the epithelial cells lining the bronchioles and alveoli that occurs with paraquat poisoning has been ascribed to excessive production of superoxide anion. Paraquat readily accepts electrons from reduced substrates of high negative potential, while the reduced paraquat reacts with molecular oxygen to form superoxide anion and an oxidized paraquat molecule ... 

Damaging mechanisms. They are grouped as follows 1. Toxic-chemical damages provoked directly by the poisonous chemical compounds, released by the aggression. 2. Thermal injuries of the respiratory tract, skin and exterior mucosa - by the heated mixture of chemical compounds and ashes. 3. Blocking of the bronchi and the bronchioles - by the penetrated ashes with the toxic gases and other hard particles and occurrence of bronchiole-alveolar block, which obstructs air and oxygen penetration in the alveoli and blood capillaries. 4. Microruptures of the respiratory tract mucosa and cerebrum concussions with violation of the membrane and intracellular structure, as well as the intracellular metabolism, due to the explosion wave and the abruptly risen pressure on the compounds of the inhaled mixture. 

Flamant C, Hallelel F, Nolent P et al (2005) Severe respiratory syncytial virus bronchiolitis in children from short mechanical ventilation to extracorporeal membrane oxygenation. Eur J Pediatr 164 93-98... 

Effects Exposure to 0.01-0.1 ppm may cause irritation and dryness of the mucous membranes. Pulmonary function may be impaired at higher concentrations. Chronic exposure leads to bronchitis, bronchiolitis, pulmonary fibrosis, and emphysema. 

Bronchioles 11-13 8,192 0.8 2.7 44.5 level airways enter the lobules as defined by a strong elastic lobular limiting membrane Not named contain no cartilage, mucus secreting elements, or cilia. Tightly... 

---