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The Juniperus ashei
The Juniperus
Ashei
To the Editor: One of the most severe and prevalent forms of allergic rhinitis in central Texas is induced by the pollenation of the cypress family. The correct name of the most common tree causing symptoms from December through February is Juniperus ashei. Among the incorrect names that have been used for this species are Juniperus sabinoides, a name that correctly pertains to a Mexican species that does not occur in the United States (Zanoni T, Adams R: Boletin de la Sociedad Botanica de MCxico 38:83, 1979; Johnston MC: Taxon 34505, 1985), and Juniperus mexicana. a synonym of J. sobinoides, and likewise inapplicable to any species occurring in the United States. Other species of Juniperus that release airborne pollen (at lower levels of abundance than that of J. ashei) include J. virginiana, J. pinchotii, and J. monospermn. A few of the traits that distinguish these species from each other are listed below. 1. J. ashei: The upper face of each leaf bears a protruding beadlike gland containing many aromatic compounds. The ripe cone is 7 to 9 mm in diameter and is dark blue with a heavy whitish bloom. This is the “cedar” that dominates most of the Edwards plateau hill country of central Texas. 2. J. monospermm of far western Texas displays dark purplish blue cones with a whitish bloom, but these are only 4 to 8 mm in diameter, and the glands of its leaves, at least on the “whip branches,” do not protrude and are not beadlike. 3. J. pinchotii has a distribution overlapping slightly that of .I. nshei, but it occurs mainly in far western Texas and the High Plains. Its ripe cones arc 6 to 10 mm in diameter and have a bronzy to red-brown color with no bloom. The glands of its leaves do not protrude. and those on the whip branches are often ruptured. 4. J. virginiana is the famous “red cedar” of southeastern United States but reaches its western limits in central Texas and the High Plains, where it occurs usually near streams (in contrast to the upland habitat of the other species). Its ripe cones. 5 to 8 mm in diameter. are dark blue with a whitish bloom, and the leaf glands are not beadlike. Plants of this species are often single trunked. stately. and “Christmas tree shaped” in contrast to the usually several trunked, irregular form of the other species mentioned. When the leaves arc viewed under a strong lens (at least x 30). the margins of the leaves arc observed to be quite devoid of teeth. whereas in the other three species the marginal cells form an irregular toothlike pattern. S/even K Find@, M .D Marshull C. Johnston, Ph.D. Allergy Center of Austin Allergy and Clinical Immunology 8701 North MOPAC Austin, 7:~ 78759 116
A suggested mechanism of action for sulfite sensitivity 7b the Editor. There have been numerous recent articles m the mcdrcai literature of reactions to sulfite, usually in the form of asthmalike respiratory symptoms after inhalation or ingestion of sulfite.’ ’ or intravenous administration of medications containing sulfite as a preservative.’ ’ Individuals with asthma are particularly sensitive to sulfite, and the reaction has been attributed to an allergic response; however. tbc response to sulfite doea not fit many criteria fos an allergjc response. There are no IgE-mediated reactions,’ no reaginic antibodies to the sulfite. and no histamine release by bitsophils after in vitro challenge by sulfite.’ There is another possible explanation for the reaction of these individual5 lo sulfite. Sulfite is a strongly nucleophilic substance hiphi? specific for attack on the disulfidc bond of proteins. Sullirc ib highly soluble in aqueous media and reactive at phy&. logic pH and temperature. Sulfite ions react with disultide groups to form S-substituted thiosulfatcs and it thiol (PSSP + SO, - PSSO, t PS i.” ’ P in thih reaction :‘r usually cystinc. the most rcactivc sulfur-containing amine: acid. Virtually all membrane proteins contain cystinc. ,rnd the disulfide bond of this amino acid (and the SH group o! its reduced form, cysteine) has been demonstrated to pIa\ a critical role in the function of many membrane proteins. including many receptors that mediate critical ceil function\. i.e.. cholinegic. adrcnergic, glucocorticoid. ins&n. .:uti cnkephalin receptors, to name a few.” When sodium bisulfite is applied to the nt,uromusculat~ junction, used as a model for ;I cholinergic tranmitter s?-i tern. in concentrations as low as IO ” mol’l.. it products $1 long-lasting change in transmitter rclcase at the presynaptic terminal and a potentiation of the postsynaptic response to acctylcholinc.” The prcsynaptic response appears to br: an attack by sulfite on a protein in the presynaptic trrmina: membrane that regulates transmitter rclcasc.” The postsyrl. aptic effect of sulfite has been dcmonstratcd !*I lit a direct attack by sulfite on a sulfhydryl group on a particular (.Gn of the cholincrgic receptor. Sulfonation at this site incrcah;\ the rcsponsc of the rcccptor to acetylcholinc. ! Sulfite &I increases the aflinity for acctvlcholinc of th.* muacarini: cholincrpic receptor of the central nervous sy\!em ” Sultitc has also been demonstrated to increase the r~+asc ol ri(:rcpinephrine from adrenergic terminals in the ircart in 1112 striatum and o&petal cortex.’ The bronchial response to sulfite has been demonstrated experimentally to involve cholincrgic receptor\ in humans. This response and the above cxpcrimental Dada on sulfite effects on the cholinergic receptor suggest XI Attack hq aulfitc on a cholinergic receptor in the lungs. in addition. the differential sensitivity to sulfhydryi rcagcnts may bt: useful: not all individuals react to them. and those: individuals with a history of asthma appear to be parriculariy XX+ sitivc. The sensitivity of these individuals may indicate :I
Ashei
To the Editor: One of the most severe and prevalent forms of allergic rhinitis in central Texas is induced by the pollenation of the cypress family. The correct name of the most common tree causing symptoms from December through February is Juniperus ashei. Among the incorrect names that have been used for this species are Juniperus sabinoides, a name that correctly pertains to a Mexican species that does not occur in the United States (Zanoni T, Adams R: Boletin de la Sociedad Botanica de MCxico 38:83, 1979; Johnston MC: Taxon 34505, 1985), and Juniperus mexicana. a synonym of J. sobinoides, and likewise inapplicable to any species occurring in the United States. Other species of Juniperus that release airborne pollen (at lower levels of abundance than that of J. ashei) include J. virginiana, J. pinchotii, and J. monospermn. A few of the traits that distinguish these species from each other are listed below. 1. J. ashei: The upper face of each leaf bears a protruding beadlike gland containing many aromatic compounds. The ripe cone is 7 to 9 mm in diameter and is dark blue with a heavy whitish bloom. This is the “cedar” that dominates most of the Edwards plateau hill country of central Texas. 2. J. monospermm of far western Texas displays dark purplish blue cones with a whitish bloom, but these are only 4 to 8 mm in diameter, and the glands of its leaves, at least on the “whip branches,” do not protrude and are not beadlike. 3. J. pinchotii has a distribution overlapping slightly that of .I. nshei, but it occurs mainly in far western Texas and the High Plains. Its ripe cones arc 6 to 10 mm in diameter and have a bronzy to red-brown color with no bloom. The glands of its leaves do not protrude. and those on the whip branches are often ruptured. 4. J. virginiana is the famous “red cedar” of southeastern United States but reaches its western limits in central Texas and the High Plains, where it occurs usually near streams (in contrast to the upland habitat of the other species). Its ripe cones. 5 to 8 mm in diameter. are dark blue with a whitish bloom, and the leaf glands are not beadlike. Plants of this species are often single trunked. stately. and “Christmas tree shaped” in contrast to the usually several trunked, irregular form of the other species mentioned. When the leaves arc viewed under a strong lens (at least x 30). the margins of the leaves arc observed to be quite devoid of teeth. whereas in the other three species the marginal cells form an irregular toothlike pattern. S/even K Find@, M .D Marshull C. Johnston, Ph.D. Allergy Center of Austin Allergy and Clinical Immunology 8701 North MOPAC Austin, 7:~ 78759 116
A suggested mechanism of action for sulfite sensitivity 7b the Editor. There have been numerous recent articles m the mcdrcai literature of reactions to sulfite, usually in the form of asthmalike respiratory symptoms after inhalation or ingestion of sulfite.’ ’ or intravenous administration of medications containing sulfite as a preservative.’ ’ Individuals with asthma are particularly sensitive to sulfite, and the reaction has been attributed to an allergic response; however. tbc response to sulfite doea not fit many criteria fos an allergjc response. There are no IgE-mediated reactions,’ no reaginic antibodies to the sulfite. and no histamine release by bitsophils after in vitro challenge by sulfite.’ There is another possible explanation for the reaction of these individual5 lo sulfite. Sulfite is a strongly nucleophilic substance hiphi? specific for attack on the disulfidc bond of proteins. Sullirc ib highly soluble in aqueous media and reactive at phy&. logic pH and temperature. Sulfite ions react with disultide groups to form S-substituted thiosulfatcs and it thiol (PSSP + SO, - PSSO, t PS i.” ’ P in thih reaction :‘r usually cystinc. the most rcactivc sulfur-containing amine: acid. Virtually all membrane proteins contain cystinc. ,rnd the disulfide bond of this amino acid (and the SH group o! its reduced form, cysteine) has been demonstrated to pIa\ a critical role in the function of many membrane proteins. including many receptors that mediate critical ceil function\. i.e.. cholinegic. adrcnergic, glucocorticoid. ins&n. .:uti cnkephalin receptors, to name a few.” When sodium bisulfite is applied to the nt,uromusculat~ junction, used as a model for ;I cholinergic tranmitter s?-i tern. in concentrations as low as IO ” mol’l.. it products $1 long-lasting change in transmitter rclcase at the presynaptic terminal and a potentiation of the postsynaptic response to acctylcholinc.” The prcsynaptic response appears to br: an attack by sulfite on a protein in the presynaptic trrmina: membrane that regulates transmitter rclcasc.” The postsyrl. aptic effect of sulfite has been dcmonstratcd !*I lit a direct attack by sulfite on a sulfhydryl group on a particular (.Gn of the cholincrgic receptor. Sulfonation at this site incrcah;\ the rcsponsc of the rcccptor to acetylcholinc. ! Sulfite &I increases the aflinity for acctvlcholinc of th.* muacarini: cholincrpic receptor of the central nervous sy\!em ” Sultitc has also been demonstrated to increase the r~+asc ol ri(:rcpinephrine from adrenergic terminals in the ircart in 1112 striatum and o&petal cortex.’ The bronchial response to sulfite has been demonstrated experimentally to involve cholincrgic receptor\ in humans. This response and the above cxpcrimental Dada on sulfite effects on the cholinergic receptor suggest XI Attack hq aulfitc on a cholinergic receptor in the lungs. in addition. the differential sensitivity to sulfhydryi rcagcnts may bt: useful: not all individuals react to them. and those: individuals with a history of asthma appear to be parriculariy XX+ sitivc. The sensitivity of these individuals may indicate :I