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HIV-1 Gag protein assembles into 100- to 120-nm diameter particles in mammalian cells. Recombinant HIV-1 Gag protein assembles in a fully defined system in vitro into particles that are only 25-30 nm in diameter and that differ significantly in other respects from authentic particles. However, particles with the size and other properties of authentic virions were obtained in vitro by addition of inositol phosphates or phosphatidylinsitol phosphates to the assembly system. Thus, the interactions between HIV-1 Gag protein molecules are altered by binding of inositol derivatives; this binding is apparently essential for normal HIV-1 particle assembly. This requirement is not seen in a deleted Gag protein lacking residues 16-99 within the matrix domain.

Background: The number of nurse scientists pursuing cross-cultural research using quantitative designs is increasing. Preparation of instruments that are conceptually and functionally appropriate in the language of the participants is a complex process that needs examination., Objectives: Brislin's classic model for translation and validation of instruments for cross-cultural research is critiqued. Adaptations and extensions of that model are recommended., Methods: Brislin's model guided tool preparation in a cross-cultural investigation. The process is described and lessons learned are outlined and discussed., Conclusions: Steps toward a more efficient and valid approach to the preparation of instruments are suggested.

The detailed preparation of deoxyribonucleoside phosphoramidites bearing a 4-[N-methyl-N-(2,2,2-trifluoroacetyl)amino]butyl group for P(III) protection is presented. The use of this group circumvents nucleobase alkylation during oligonucleotide deprotection. Two syntheses of phosphoramidites starting from either a phosphordichloridite precursor or a bis-(N,N-diisopropylamino)chlorophosphine intermediate are described for the phosphinylation of suitably protected deoxyribonucleosides.

Interactions of sulfhydryl reagents with introduced cysteines in the pore-forming (Kir6.2) subunits of the K(ATP) channel were examined. 2-Aminoethyl methanethiosulfonate (MTSEA(+)) failed to modify Cd(2+)-insensitive control-Kir6.2 channels, but rapidly and irreversibly modified Kir6.2[L164C] (L164C) channels. Although a single Cd(2+) ion is coordinated by L164C, four MTSEA(+) "hits" can occur, each sequentially reducing the single-channel current. A dimeric fusion of control-Kir6.2 and L164C subunits generates Cd(2+)-insensitive channels, confirming that at least three cysteines are required for coordination, but MTSEA(+) modification of the dimer occurs in two hits. L164C channels were not modified by bromotrimethyl ammoniumbimane (qBBr(+)), even though qBBr(+) caused voltage-dependent block (as opposed to modification) that was comparable to that of MTSEA(+) or 3-(triethylammonium)propyl methanethiosulfonate (MTSPTrEA(+)), implying that qBBr(+) can also enter the inner cavity but does not modify L164C residues. The Kir channel pore structure was modeled by homology with the KcsA crystal structure. A stable conformation optimally places the four L164C side chains for coordination of a single Cd(2+) ion. Modification of these cysteines by up to four MTSEA(+) (or three MTSPTrEA(+), or two qBBr(+)) does not require widening of the cavity to accommodate the derivatives within it. However, like the KcsA crystal structure, the energy-minimized model shows a narrowing at the inner entrance, and in the Kir6.2 model this narrowing excludes all ions. To allow entry of ions as large as MTSPTrEA(+) or qBBr(+), the entrance must widen to >8 A, but this widening is readily accomplished by minimal M2 helix motion and side-chain rearrangement.

Although caregiving has been studied extensively, most studies have focused on the activities performed by caregivers, problems encountered and caregivers' reactions. Less attention has been paid to measuring historical and interpersonal factors that may shape the situation and affect outcomes, but are not necessarily embedded in the role itself. The objective of this article is to report on the development and testing of the Elder Image Scale (EIS) which indexes the personal identity of the elder, the mental image the caregiver has of the elder derived from past associations, present observations, and the reconciliation of the past with present impressions. This scale was based on the Family Caregiving Dynamics Model and the personal image of the elder is predicted to be shaped by certain structural factors and to impact both the perceptions of caregivers and the outcomes of caregiving. This article reports on four separate investigations; six-hundred-and-fifty-six caregivers participated. The EIS is in the semantic differential format. Internal consistency ranged from .92 to .98 over four studies. Stability after two weeks was .93 for both subscales. All correlations with criteria were in the direction predicted and most were significant. Known group comparisons showed all group differences were statistically significant as predicted. The EIS is internally consistent, stable and evidences construct validity. In addition, measuring this concept appears to have great relevance for explaining both perceptions of caregivers and outcomes of caregiving.

Domestic violence against women is a significant health problem in this country and worldwide. A group that has been neglected, however, in discussions of this problem are older women. Although one might assume that domestic violence against older women is included in discussions of elder abuse, that body of literature actually may obscure the problem for several reasons. This article discusses the background of domestic violence against older women in two contexts: long-standing wife abuse and abuse of aging caregivers. Suggestions for assessment and intervention are included.