| 1. |
- Hesselmar, Bill, 1955, et al.
(författare)
-
Building characteristics affect the risk of allergy development
- 2005
-
Ingår i: Pediatr Allergy Immunol. - : Wiley. - 0905-6157 .- 1399-3038. ; 16:2, s. 126-31
-
Tidskriftsartikel (refereegranskat)abstract
- Damp dwellings increase the risk for house dust mite (HDM) infestation in temperate climate zones and may be associated with an increased risk for allergic disease. The aim of the study was to assess possible relationships between allergen levels in house dust, characteristics of residence buildings and allergic diseases in children. A subsample of 12-yr-old children, having the same address in 1991 and 1996, was selected from a population-based sample of children from the Goteborg area. Health inspectors examined the residences of all the 109 children and several different building characteristics including humidity and indoor temperature were collected. Dust samples for analysis of HDM allergens were collected from the children's beds, and for analysis of cat and dog allergens from the living room. Current health status was assessed by questionnaires, interviews and skin prick tests (SPT). Dog or cat allergens were found in all houses, even in houses without such animals. HDM allergens were found in 60% of the houses, but only six of them had levels exceeding 2 microg/g dust. There was a strong association between HDM-infestation and wheeze, but not with specific sensitization to HDM. The type of building (houses when compared with flats), the ventilation system and the presence of a basement had all major implications on respiratory symptoms, atopy and HDM infestation. We can conclude that dog or cat allergens were found in all houses, and a strong association between HDM infestation and indoor environment. Building construction affected both respiratory morbidity and sensitisation independently, suggesting not only worsening of symptoms but also a causative relationship with disease development.
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Samec, Joseph S. M., et al.
(författare)
-
Mechanistic study of hydrogen transfer to imines from a hydroxycyclopentadienyl ruthenium hydride. Experimental support for a mechanism involving coordination of imine to ruthenium prior to hydrogen transfer
- 2006
-
Ingår i: Journal of the American Chemical Society. - Washington, DC : American Chemical Society (ACS). - 0002-7863 .- 1520-5126. ; 128:44, s. 14293-14305
-
Tidskriftsartikel (refereegranskat)abstract
- Reaction of [2,3,4,5-Ph-4(eta(5)-C4COH) Ru(CO)(2)H] (2) with different imines afforded ruthenium amine complexes at low temperatures. At higher temperatures in the presence of 2, the complexes decomposed to give [Ru-2(CO)(4)(mu-H)(C4Ph4COHOCC4Ph4)] (1) and free amine. Electron-rich imines gave ruthenium amine complexes with 2 at a lower temperature than did electron-deficient imines. The negligible deuterium isotope effect (k(RuHOH)/k(RuDOD) = 1.05) observed in the reaction of 2 with N-phenyl[1-(4-methoxyphenyl) ethylidene]amine (12) shows that neither hydride (RuH) nor proton (OH) is transferred to the imine in the rate-determining step. In the dehydrogenation of N-phenyl-1-phenylethylamine (4) to the corresponding imine 8 by [2,3,4,5-Ph-4(eta(4)-C4CO) Ru(CO)(2)] (A), the kinetic isotope effects observed support a stepwise hydrogen transfer where the isotope effect for C-H cleavage (k(CHNH)/k(CDNH) = 3.24) is equal to the combined (C-H, N-H) isotope effect (k(CHNH)/k(CDND) = 3.26). Hydrogenation of N-methyl(1-phenylethylidene) amine (14) by 2 in the presence of the external amine trap N-methyl-1-(4-methoxyphenyl) ethylamine (16) afforded 90-100% of complex [2,3,4,5-Ph-4(eta(4)-C4CO)] Ru(CO)(2)NH(CH3)(CHPhCH3) (15), which is the complex between ruthenium and the amine newly generated from the imine. At -80 degrees C the reaction of hydride 2 with 4-BnNHsC(6)H(9)=NPh (18), with an internal amine trap, only afforded [2,3,4,5-Ph-4(eta(4)-C4CO)](CO)(2)RuNH(Ph)(C6H10-4-NHBn) (19), where the ruthenium binds to the amine originating from the imine, showing that neither complex A nor the diamine is formed. Above -8 degrees C complex 19 rearranged to the thermodynamically more stable [Ph-4(eta(4)-C4CO)](CO)(2)RuNH(Bn)(C6H10-4-NHPh) (20). These results are consistent with an inner sphere mechanism in which the substrate coordinates to ruthenium prior to hydrogen transfer and are difficult to explain with the outer sphere pathway previously proposed.
|
|
| 6. |
|
|
