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A Lipman

Publications and source records attributed to A Lipman.

17 recordsLinked to original sources
PubMed2000

Damage to liposomal lipids: protection by antioxidants and cholesterol-mediated dehydration.

Liposomes composed of egg phosphatidylcholine (EPC) (13.4%, of the acyl chains being polyunsaturated fatty acids (PUFA)) and EPC/cholesterol (10:1 mol/mol) were studied for factors that affect liposomal lipid oxidative damage and hydrolysis upon long-term (16 months) storage. Factors studied include: (1) levels of lipid/water interface hydration, related to the presence of cholesterol in the lipid bilayer; (2) the membrane-associated antioxidant vitamin E; (3) the water-soluble antioxidant Tempol; and (4) exposure to light. Liposomal dispersions were stored at room temperature, either exposed to or protected from daylight, for a period of 16 months. Chemical and physical changes were monitored at several time points to assess oxidative and hydrolytic degradation of liposomal lipids. The conclusions of the study are: (1) PUFA are the most sensitive component of the liposome bilayer to oxidative degradation damage during long-term storage; (2) EPC liposomes are more sensitive to degradation during storage than EPC cholesterol liposomes, the presence of cholesterol in the lipid bilayer having a protective effect, probably due to its effect in decreasing the lipid-bilayer hydration; (3) oxidative degradation is the major process during long-term storage, having an earlier onset than the hydrolytic degradation: and (4) Tempol provided significantly better protection than vitamin E to EPC liposomal PUFA against oxidative damage during long-term storage. The relevance of cholesterol's presence, as a 'drying agent', in membranes containing PUFA to resistance of biological membranes to oxidative damage is discussed.

2-Naphthylamine↗
PubMed1982

The married, the formerly married and the never married: support system differentials of older women in planned retirement communities.

This paper explores the nature of informal support given to older women, depending upon their marital status and the presence of living children. To control for differential availability of formal resources and for background characteristics, random samples of 371 noninstitutionalized female residents of two midwestern life care communities were interviewed. We found, unsurprisingly, that women who were presently, or who had been married, received more emotional, social, and instrumental support from their family members. But in further analysis it became clear, much to our surprise, that the presence of a husband only assured the married women of significantly more instrumental (task-oriented) support. It was the existence of living children--even just one child--that generated greater emotional, social, and instrumental support from her family. The greatest informal support deficits are among the never married, as expected, but are a result of the lack of children rather than the absence of a husband.

Aged↗
PubMed1979

The quality of verbal interaction in homes for old people.

Some 4,500 verbal exchanges among residents, and between staff and residents were recorded during structured observations in eight British purpose-built Homes for old people. These interactions were initially categorised as 'supportive/acceptive' or as 'other'. Subsequently, the 'other' data from four of the Homes was further classified as 'instrumental' and 'unclassifiable'. The participants in the exchanges were noted (resident or staff) as was the mental status assigned to residents ('confused' or 'rational'). The data suggest that interactions among residents are more likely to be supportive/acceptive than are those between staff and residents; that, similarly, interactions among rational residents are more likely to be supportive than those between rational and confused residents, or than those among confused residents. Interactions between rational and confused residents are more likely to be supportive than those among confused patients. Further, the data indicate that interactions between staff and rational residents, and between staff and confused residents do not differ in quality; predominantly, interactions between staff and residents are instrumental. These interpretations of the data are discussed in relation to the care of residents in institutional settings.

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PubMed1977

Architectural design: the spatial location and interactions of old people.

Residents' interactions in the sitting spaces of purpose-built Homes for old people were studied by participant and structural observation. Eight Homes were sampled from a larger number to represent factors of size (large and small), design (institutional and family) and mental designation of residents (confused or rational). Verbal exchanges between residents were analysed in terms of initiators' and respondents' mental designations. The residents' locations within the sitting spaces and in the sleeping and dining areas of the Homes were recorded. Examination of these data suggests that residents of different mental designations are segregated from each other. Some architectural design elements of physical settings that might foster integration are outlined.

Aged↗