Perspectives on metaphyseal conservative stems.

Total hip replacement is showing, during the last decades, a progressive evolution toward principles of reduced bone and soft tissue aggression. These principles have become the basis of a new philosophy, tissue sparing surgery. Regarding hip implants, new conservative components have been proposed and developed as an alternative to conventional stems. Technical and biomechanical characteristics of metaphyseal bone-stock-preserving stems are analyzed on the basis of the available literature and our personal experience. Mayo, Nanos and Metha stems represent, under certain aspects, a design evolution starting from shared concepts: reduced femoral violation, non-anatomic geometry, proximal calcar loading and lateral alignment. However, consistent differences are level of neck preservation, cross-sectional geometry and surface finishing. The Mayo component is the most time-tested component and, in our hands, it showed an excellent survivorship at the mid-term follow-up, with an extremely reduced incidence of aseptic loosening (partially reduced by the association with last generation acetabular couplings). For 160 implants followed for a mean of 4.7 years, survivorship was 97.5% with 4 failed implants: one fracture with unstable stem, 1 septic loosening and 2 aseptic mobilizations. DEXA analysis, performed on 15 cases, showed a good calcar loading and stimulation, but there was significant lateral load transfer to R3-R4 zones, giving to the distal part of the stem a function not simply limited to alignment. Metaphyseal conservative stems demonstrated a wide applicability with an essential surgical technique. Moreover, they offer the options of a "conservative revision" with a conventional primary component in case of failure and a "conservative revision" for failed resurfacing implants.

Further evidence against the implication of active cytomegalovirus infection in vascular atherosclerotic diseases.

The possible contribution of cytomegalovirus (CMV) to pathogenetic events associated with atherosclerotic lesion establishment and progression is still controversial. We evaluated the possibility that active ongoing CMV infection could be correlated to evolution of unstable atheromatous lesion, by analyzing patients suffering from unstable angina (n=61), acute myocardial infarction (n=43), stable angina (n=26) and peripheral arteriopathy (n=22) as compared to healthy subjects (n=30). Particularly, we assessed: past exposure to CMV by evaluating anti-CMV IgG antibodies; ongoing CMV infection by evaluating anti-CMV IgM antibodies and circulating interleukin (IL)-8 in serum; and CMV DNAemia in peripheral blood mononuclear cells (PBMC). Mean IgG values were significantly increased in patients from all groups, as compared to healthy subjects. CMV-specific IgM, as well as CMV DNAemia, were undetectable in both controls and patients. Circulating IL-8, significantly elevated in a group of individuals experiencing active CMV infection, was not significantly higher in cardiovascular disease patients, as compared to control subjects. These findings confirm previous evidence from the increased exposure to CMV infection in patients with atheromatous lesions. However, they provide further evidence against a direct implication of active systemic CMV infection in the pathogenesis of cardiovascular diseases, particularly those involving plaque instability.

Alpha interferon inhibits human herpesvirus 8 (HHV-8) reactivation in primary effusion lymphoma cells and reduces HHV-8 load in cultured peripheral blood mononuclear cells.

Infection by human herpesvirus 8 (HHV-8) is associated with the development of Kaposi's sarcoma (KS). Since regression of KS can be achieved by treatment of the patients with alpha interferon (IFN-alpha), we analyzed the effects of IFN-alpha or anti-IFN-alpha antibodies (Ab) on HHV-8 latently infected primary effusion lymphoma-derived cell lines (BCBL-1 and BC-1) and on peripheral blood mononuclear cells (PBMC) from patients with all forms of KS and from at-risk subjects. IFN-alpha inhibited in a dose-dependent manner the amplification of HHV-8 DNA in BCBL-1 cells induced to lytic infection with tetradecanoyl phorbol acetate (TPA). This effect was associated with the inhibition of the expression of HHV-8 nut-1 and kaposin genes that are induced early and several hours, respectively, after TPA treatment. In addition, IFN-alpha inhibited virus production and/or release from BCBL-1 cells. Inhibition of nut-1 and kaposin genes by IFN-alpha was also observed in BC-1 cells induced with n-butyrate. Conversely, the addition of anti-IFN-alpha Ab to TPA-induced BCBL-1 cells resulted in a larger number of mature enveloped particles and in a more extensive cytopathic effect due to the neutralization of the endogenous IFN produced by these cells. IFN was also produced by cultured PBMC from HHV-8-infected individuals, and this was associated with a loss of viral DNA during culture. However, the addition of anti-IFN-alpha Ab or anti-type I IFN receptor Ab promoted the maintenance of HHV-8 DNA in these cells that was associated with the detection of the latency-associated kaposin RNA. Finally, the addition of IFN-alpha reduced the HHV-8 load in PBMC. Thus, IFN-alpha appears to have inhibitory effects on HHV-8 persistent infection of PBMC. These results suggest that, in addition to inhibiting the expression of angiogenic factors that are key to KS development, IFN-alpha may induce KS regression by reducing the HHV-8 load and/or inhibiting virus reactivation.

Human immunodeficiency virus type 1 gp120 stimulates cytomegalovirus replication in monocytes: possible role of endogenous interleukin-8.

Recombinant gp120, but not other human immunodeficiency type 1 (HIV-1) structural proteins, dose-dependently stimulates human cytomegalovirus (HCMV) immediate-early antigen (IEA) expression and infectious virus yield in freshly isolated normal monocytes infected with HCMV. Monoclonal antibodies (MAbs) recognizing the gp120 V3 loop, as well as V3 loop octameric multibranched peptides and antibody to galactocerebroside, but not sCD4, abrogate the gp120 stimulation of IEA expression, suggesting that the effect involves V3 loop-galactocerebroside interaction and is not mediated by CD4. Interleukin 8 (IL-8) gene expression is enhanced in monocytes treated with gp120 at the level of both mRNA and released protein. Exogenous IL-8 could replace gp120 in the stimulation of HCMV infection, while a MAb capable of neutralizing IL-8 activity abrogates the gp120-induced HCMV stimulation. These data indicate that HIV-1 glycoprotein induces stimulation of productive infection of monocytes with HCMV and that such stimulation may be mediated by the upregulation of IL-8 gene expression. This is the first evidence that HIV-1 may affect HCMV replication indirectly, via the interaction of gp120 with the monocyte membrane, in the complete absence of retroviral replication, through the stimulation of IL-8 release. Because in HIV-1-infected individuals, HCMV infection is frequently activated and the levels of circulating IL-8 are enhanced, these findings may be pathogenetically relevant.

Interferon gamma stimulates cell-mediated transmission of HIV type 1 from abortively infected endothelial cells.

Human umbilical vein endothelial cells (HUVEC) can be abortively infected with HIV-1, but virus production is rescued by T cells. The influence of interferon gamma (IFN-gamma) in this experimental system has been investigated. HUVEC either untreated or treated with IFN-gamma were infected with HIV-1 and cocultivated with rescuer T cells. Virus yield was subsequently assessed as antigen or infectivity present in the cocultures supernatants. Viral DNA in HUVEC was detected by polymerase chain reaction. Transmission electron microscopy was used to establish direct interactions between HUVEC and T cells. Intercellular adhesion molecule (ICAM)-1 expression by HUVEC was measured by enzyme-linked immunoassay. Monoclonal antibodies (MAbs) to adhesion molecules were used to block the rescue of infection by T cells. Treatment of HUVEC with IFN-gamma caused a dose-dependent enhancement of HIV-1 yield in cocultures of HUVEC with either lymphoblastoid or normal T cells. IFN-gamma was effective also when administered to HUVEC 1 day after infection. Neither HIV-1 adsorption nor virus reverse transcription was stimulated by IFN. Physical contact between HIV-1-infected HUVEC and rescuer T cells was observed, and discrete tracts of discontinuity between the juxtaposed membranes were detected, being more frequent when HUVEC had been treated with IFN-gamma. Treatment with IFN determined an increase of ICAM-1 expression by HUVEC, and anti ICAM-1 MAbs inhibited HIV-1 rescue, being more effective when HUVEC had been exposed to IFN-gamma. Treatment of T cells with anti-LFA-1 Mab also inhibited HIV-1 rescue. The enhancing effect of IFN-gamma could be the result of stimulated transfer of HIV-1 infection from HUVEC to T cells, possibly mediated by enhanced expression of ICAM-1 by HUVEC, that could, in turn, enhance the efficiency of membrane interaction with T cells. Since in HIV-1-infected patients circulating IFN-gamma is enhanced, our results can have pathogenetic implications.

Health care professionals and family involvement in care-related decisions concerning older patients.

This article examines care-related decision making within the context of in-home family care. It also uses the Andersen-Newman model to identify the correlates of physician involvement and centrality in decision making and the impact that it has on family members' caregiving satisfaction. Analysis of data from 244 family caregivers shows that elders (40%) and nuclear kin (53%) are key decision makers, indicating that families prefer to control care-related decisions. However, physicians are part of the decision-making process for nearly one fourth of the families in this study. The patient's impairment and the caregiver's education correlate with physician involvement in decision making. Shared residence and caregiver's overall satisfaction with the caregiving process correlate with physician centrality on the network. Discussion centers on implications for physician interactions with caregiving families around decision making. Included are indications for improved communication in decision-making contexts.

Environmental satisfaction, sociability, and well-being among urban elderly.

A review of the literature indicates that until recently little attention has been paid to the effects of the environment on well-being among the aged. This study analyzes data relevant to both the individual and his or her environment from a large (N = 2265) national sample of low- and middle-income elderly. A recursive causal model is presented; the results indicate that perceived health and housing satisfaction contribute the most to well-being among the elderly. In addition, for men and women home ownership was not found to affect well-being positively. For men who owned their own homes lower scores on well-being were reported. The findings also indicate that while the quantity of neighbor interaction benefits the well-being of men, women benefit more from the positive sentiments of sociability in the neighborhood. This study emphasizes the importance of environmental satisfaction and neighborhood sociability as key determinants of well-being in later life.