Cubane tetrameric complexes of copper(I) chloride and bromide with triphenyl phosphite.

The crystal structures of tetra-mu 3-chloro-tetrakis[(triphenyl phosphite-P)copper(I)], [Cu4Cl4(C18H15O3P)4], and tetra-mu 3-bromo-tetrakis [(triphenyl phosphite-P)-copper(I)], [Cu4Br4(C18H15O3P)4], are described. Both have distorted 'cubane' Cu4X4 cores. Distortion of the cubane structure is reflected in X-Cu-X angles > 90 degrees and Cu-X-Cu angles < 90 degrees, and is more pronounced in the bromide complex.

Active Role of a Germylene Ligand in Promoting Reactions of Platinum Complexes with Oxygen and Sulfur Dioxide.

The reaction of (Et(3)P)(2)PtGe[N(SiMe(3))(2)](2) with dioxygen yields (Et(3)P)(2)Pt(&mgr;-eta(2)-O(2))Ge[N(SiMe(3))(2)](2) (1). Exposure of 1 to light resulted in a rearrangement to (Et(3)P)(2)PtO(2)Ge[N(SiMe(3))(2)](2) (2a), the first example of a bidentate, dianionic germanate ligand. The isomerization was judged to occur via an intramolecular O-O bond scission and rotation of the Pt-Ge bond. No free germylene was detected, and the reaction was found to be zero order. An analogue of 2a was prepared by direct reaction of (Ph(3)P)(2)PtO(2) with Ge[N(SiMe(3))(2)](2) yielding (Ph(3)P)(2)PtO(2)Ge[N(SiMe(3))(2)](2) (2b). Addition of SO(2) to 1 results in the formation of the bridging sulfate (Et(3)P)(2)Pt(&mgr;-eta(2)-SO(4))Ge[N(SiMe(3))(2)](2) (3). An infrared spectroscopy study of the sulfate reaction was performed using oxygen-18. The results indicate that direct insertion of SO(2) into the O-O bond does not occur. Formaldehyde was also observed to insert into the Pt-O bond of 1 giving (Et(3)P)(2)Pt(&mgr;-eta(2)-OCH(2)OO)Ge[N(SiMe(3))(2)](2) (5).

Predominant tree aeroallergens of the Washington, DC area: a six year survey (1989-1994).

OBJECTIVE: A 6-year (1989 to 1994) aerobiologic survey of the Washington DC area was performed to identify predominant area tree pollens, atmospheric concentrations, and peak flowering periods. METHODS: Aeroallergen sampling was conducted using a volumetric rotating-arm impaction Rotorod sampler (Sampling Technologies, Inc, Los Altos Hills, California). RESULTS: The Washington DC pollen calendar may begin as early as January when pollen of the Cupresseacea, Aceracea, Pinaceae, and Betulaceae are observed in small amounts. February through June encompasses the major part of our tree season with considerable overlapping of pollination periods for various trees. The Ulmaceae have two distinct pollinating times with later flowering species of elm pollinating August through October coinciding with ragweed season. April is usually the month with the highest weekly average concentrations. Each year oaks contribute more than 50% of the total tree pollen count followed by pollen of the Pinacea, Cupresseacea, Moracea, and Betuleacea. Times for onset of pollination as well as peak atmospheric concentrations varied from year to year. High production years for some tree aeroallergens are low years for others. CONCLUSION: The Washington DC area is exposed to significant atmospheric concentrations of tree pollen from February through June. Establishing what area tree aeroallergens predominate with respect to their atmospheric concentrations and peak pollinating times is essential for the effective diagnosis and treatment of the tree-allergic patient.

Azidotetrakis(trimethylphosphine)nickel(II) tetrafluoroborate.

The title complex, [Ni(N3)(C3H9P)4]BF4, is a nearly perfect trigonal bipyramid with the azide group at an apical position. The metal-azide bond angle, Ni1--N1--N2, of 138.6(5) degrees is the largest observed for a terminal azide ligand.

Mosquito bite anaphylaxis: immunotherapy with whole body extracts.

BACKGROUND: Adverse reactions to mosquito bites have been recognized for some time. These usually consist of large local swellings and redness, generalized urticaria, angioedema and less easily definable responses such as nausea, dizziness, headaches, and lethargy. METHODS: We report two patients who experienced systemic anaphylaxis from mosquito bites. Both were skin tested and given immunotherapy using whole body mosquito extracts. RESULTS: Skin testing using whole body mosquito extracts was positive to Aedes aegypti at 1/1,000 weight/volume (wt/vol) in one patient and to Aedes aegypti at 1/100,000 wt/vol, and Culex pipiens at 1/10,000 wt/vol in the other. Skin testing of ten volunteers without a history of adverse reactions to mosquito bites was negative. Immunotherapy using these extracts resulted in resolution of adverse reactions to mosquito bites in one patient and a decrease in reactions in the other. CONCLUSIONS: Immunotherapy with whole body mosquito extracts is a viable treatment option that can play a role in patients with mosquito bite-induced anaphylaxis. It may also result in severe side effects and one must determine the benefit versus risks for each individual patient.

Mite allergen control with acaricide fails.

BACKGROUND: We compared the effects of an acaricide, benzyl benzoate, with the effects of baking soda control applied to bedroom and living room carpets on house dust mite allergen levels, lung function, and medication use in 12 adult patients with asthma for 12 months. METHODS: This was a randomized, double-blind, placebo-controlled study. Patients were enrolled from the allergy clinic of a large tertiary care center in a metropolitan area. All patients had positive dust mite puncture test results. Six patients used benzyl benzoate, and six used baking soda. Other aggressive mite control measures were implemented uniformly in each group. Subjects were to make two carpet applications, at baseline and at 6 months according to the manufacturer's recommendations. Dust samples were collected in bedroom and living room carpets at 0, 3, 6, 9, and 12 months; and quantities of Der p I and Der f I allergens were determined. Spirometry was done every 3 months, and peak flow rates were recorded for 10 days after each dust sampling. RESULTS: There were no significant differences in mean allergen levels between the two groups over time at either site. There were no significant changes in lung function or medication use for either group. CONCLUSIONS: Benzyl benzoate powder applications may not be effective when done according to manufacturer's instructions. Further studies are necessary to test effectiveness when applied more frequently and for longer periods.

Treatment options in the child with a chronic cough.

Chronic cough is a common symptom in many different disease processes. Because the most effective way to eliminate a chronic cough is to identify and treat the underlying disease, the physician must approach the paediatric patient based on his or her knowledge of the differential diagnosis. The most common causes of cough in children are upper respiratory tract infections, asthma, rhinitis, sinusitis, and gastroesophageal reflux. By using a systematic approach, the cause of a chronic cough can almost always be found, and the cough successfully treated. Asthma is the cause of most undiagnosed chronic coughs but sinusitis, rhinitis, and gastroesophageal reflux must also be considered in difficult patients.

Bird antigen persistence in the home environment after removal of the bird.

Hypersensitivity pneumonitis (HP) secondary to bird exposure is treated with glucocorticosteroids and avoidance. Despite therapy, symptoms may persist for a prolonged time. Just as cat antigen, Fel d 1, may persist for greater than 20 weeks after cat removal, there may be persistent bird antigen to explain prolonged symptoms in bird HP. It was the intent of this study to determine household distribution and persistence of bird antigen after removal of the bird from the patient's home. The homes of patients with birds were followed serially after bird removal with multiple samples collected using a hand-held vacuum cleaner. Bird antigen levels were determined by an inhibition enzyme-linked immunoassay. In five homes the antigen declined gradually despite extensive environmental control measures, with high levels still detectable at 18 months in one home. This data suggests that high levels of bird antigen can be detected for prolonged periods of time after bird removal and environmental cleanup. The antigen may account for the persistence of disease in some patients with HP. In severe HP, the preferred therapy may be temporary relocation of the patient away from the room in which the bird was housed, in addition to corticosteroids, until the patient's environment is demonstrated to be relatively bird antigen-free.

Effective education of adults with asthma who are allergic to dust mites.

The effects of supplementary computer instruction in house dust mite-avoidance measures on adherence to implementing measures, on home dust mite-allergen levels, and on symptomatology were investigated in 52 adult patients with mite-associated asthma. Twenty-six patients received conventional instruction (counseling and written instruction) and the other 26 patients received conventional plus 22 minutes of interactive computer-assisted instruction. Instructions were aimed at mite-avoidance measures. Pre- and postinstruction dust samples were collected, and adherence was monitored. All patients kept symptom diaries twice a day. Patients' progress was followed for 12 weeks, and all patients completed the study. Adherence, number of observed and self-reported mite-avoidance measures implemented after visit, was higher for the computer group (p = 0.023). The computer-instructed group achieved significantly lower levels of mite allergen in bedroom carpets (p = 0.004) with mean levels of mite allergen declining from 6.5 +/- 7.6 to 2.2 +/- 4.3 micrograms/gm of dust (two-site monoclonal antibody assays), whereas levels for the conventional-instructed group did not change. Moreover, by study weeks 9 and 10, the computer-instructed group was significantly less symptomatic (p = 0.033). Mean symptom scores for this group decreased from 12.4 to 7.7, compared with 16.4 to 14.3. Conventional instruction supplemented with computer instruction is suggested in mite education.

Febrile reaction to inhaled acetylcysteine.

This report describes a hitherto unreported severe reaction to aerosolized acetylcysteine (Mucomyst). It was documented by bronchial provocation.

Evaluation of combined H1- and H2-receptor blocking agents in the treatment of seasonal allergic rhinitis.

During an 8 wk period (September 23 to July 30) 23 patients with histories of late-summer allergic rhinitis received, on a random basis, alternating 2 wk courses of either chlorpheniramine (anti-H1), 12 to 48 mg/day, plus placebo, or anti-H1 in the same dose plus cimetidine (anti-H2), 300 mg t.i.d. Symptom (SX) and medication (MED) scores were recorded twice daily. After the season the immediate (ICR) and late (LCR) reactions to allergens and histamine were measured in six of these patients while on: (1) no drugs, (2) anti-H1 plus placebo, or (3) anti-H1 plus anti-H2 in the doses employed during the season. Mean weekly SX scores were significantly lower on anti-H1 plus anti-H2 compared with anti-H1 plus placebo during the sixth week of the study (p less than 0.001). MED scores were lower on the anti-H1 and anti-H2 combination than on anti-H1 alone during weeks four and five (p less than 0.02). In the six patients studied after the season, the ICRs were consistently smaller with the anti-H1 and anti-H2 combination, but the differences were only significant for the histamine-induced wheal (p less than 0.01). In this study of allergic rhinitis there appeared to be a small but statistically significant additive effect of anti-H2 to the clinical response to anti-H1. No additional side effects were noted.