Centerscope

Centerscope, formerly Scope, was published by the Boston University Medical Center "to communicate the concern of the Medical Center for the development and maintenance of improved health care in contemporary society.

The HIV Seropositive State and Progression to AIDS: An Overview of Factors Promoting Progression

We have considered factors that predispose to infection by the human immunodeficiency virus as well as the clinical consequences of infection. We have also reviewed what is known about the virological status of the asymptomatic carrier, particularly the female, and the fact that pregnancy may be a cofactor for progression of HIV disease in seropositive women. Additionally, we have discussed several other cofactors that may promote the progression of HIV infection. These include intercurrent infection, excessive use of recreational drugs and alcohol, malnutrition, and stress. With respect to stress, we have reviewed evidence indicating that certain personality factors, by buffering the effects of stress, may play a role in determining the outcome of HIV disease. Possible neuromodulators that may mediate the effect(s) of stress on the immune system are considered. Also discussed is the potentially complicating role of HIV infection of the brain of asymptomatic carriers on psychosocial studies, as well as the possible dysregulation of neuromodulator levels which might result from such infection. The possibility that HIV infection of the brain may act to enhance progression of HIV infection is proposed

Humphrey Center News: Spring/Summer 1986 v. 2, no. 2

Newsletter of the Hubert H. Humphrey Cancer Research Center at Boston University School of Medicine

CONTACT-INHIBITED REVERTANT CELL LINES ISOLATED FROM SV40-TRANSFORMED CELLS : IV. Microfilament Distribution and Cell Shape in Untransformed, Transformed, and Revertant Balb/c 3T3 Cells

A comparison is made of the ultrastructure of the cell periphery in three cloned cell lines: untransformed Balb/c 3T3 cells, SV40-transformed Balb/c 3T3 cells, and revertant cells obtained from the transformed cell line by a selection technique utilizing concanavalin A. Both thin-section and surface replication techniques are used for in situ examination of the cell lines. Microfilaments, 70 Å in diameter (called alpha filaments), are abundant in untransformed and revertant cell lines, particularly in the anterior expansions of the cells, which tend to have many microvilli and small pseudopodia. Alpha filaments are diminished in the anterior expansions of transformed cells, which contain large blunt pseudopodia and relatively few microvilli. Surface replicas confirm the impression gained from thin sections that transformed cells have a greater proportion of their cell surface involved in bulging pseudopodia than either untransformed or revertant cells. Since alpha filaments are shown to bind heavy meromyosin and are similar to F-actin, these filaments are thought to be important in cell motility. These observations suggest that a close relationship exists between decreased alpha filaments, bulging pseudopodia, and loss of contact inhibition of movement in transformed cells

Stochastic Cellular Automata Model for Stock Market Dynamics

In the present work we introduce a stochastic cellular automata model in order to simulate the dynamics of the stock market. A direct percolation method is used to create a hierarchy of clusters of active traders on a two dimensional grid. Active traders are characterised by the decision to buy, (+1), or sell, (-1), a stock at a certain discrete time step. The remaining cells are inactive,(0). The trading dynamics is then determined by the stochastic interaction between traders belonging to the same cluster. Most of the stylized aspects of the financial market time series are reproduced by the model.Comment: 17 pages and 7 figure

Persistence of the immune response induced by BCG vaccination.

BACKGROUND: Although BCG vaccination is recommended in most countries of the world, little is known of the persistence of BCG-induced immune responses. As novel TB vaccines may be given to boost the immunity induced by neonatal BCG vaccination, evidence concerning the persistence of the BCG vaccine-induced response would help inform decisions about when such boosting would be most effective. METHODS: A randomised control study of UK adolescents was carried out to investigate persistence of BCG immune responses. Adolescents were tested for interferon-gamma (IFN-gamma) response to Mycobacterium tuberculosis purified protein derivative (M.tb PPD) in a whole blood assay before, 3 months, 12 months (n = 148) and 3 years (n = 19) after receiving teenage BCG vaccination or 14 years after receiving infant BCG vaccination (n = 16). RESULTS: A gradual reduction in magnitude of response was evident from 3 months to 1 year and from 1 year to 3 years following teenage vaccination, but responses 3 years after vaccination were still on average 6 times higher than before vaccination among vaccinees. Some individuals (11/86; 13%) failed to make a detectable antigen-specific response three months after vaccination, or lost the response after 1 (11/86; 13%) or 3 (3/19; 16%) years. IFN-gamma response to Ag85 was measured in a subgroup of adolescents and appeared to be better maintained with no decline from 3 to 12 months. A smaller group of adolescents were tested 14 years after receiving infant BCG vaccination and 13/16 (81%) made a detectable IFN-gamma response to M.tb PPD 14 years after infant vaccination as compared to 6/16 (38%) matched unvaccinated controls (p = 0.012); teenagers vaccinated in infancy were 19 times more likely to make an IFN-gamma response of > 500 pg/ml than unvaccinated teenagers. CONCLUSION: BCG vaccination in infancy and adolescence induces immunological memory to mycobacterial antigens that is still present and measurable for at least 14 years in the majority of vaccinees, although the magnitude of the peripheral blood response wanes from 3 months to 12 months and from 12 months to 3 years post vaccination. The data presented here suggest that because of such waning in the response there may be scope for boosting anti-tuberculous immunity in BCG vaccinated children anytime from 3 months post-vaccination. This supports the prime boost strategies being employed for some new TB vaccines currently under development

Factors Influencing Sun Protection Behaviors among Patients with Skin Cancer: An Application of the Information-Motivation-Behavioral Skills Model

© 2019 by the Dermatology Nurses\u27 Association. This study aimed to assess predictors of sun protection behaviors based on the information-motivation-behavioral skills (IMB) model among people diagnosed with nonmelanoma skin cancer (NMSC). For this descriptive, cross-sectional study, a convenience sample of 311 patients with NMSC was recruited at a medical center in Mississippi. Patients were invited to complete a face- A nd content-valid, IMB-model-based questionnaire. The average age of the participants was 64.12 (±12.02) years, and most (58.8%) were male. Most participants indicated not using sun protection behaviors while outdoors. Findings showed that sun protection behaviors were directly predicted by self-efficacy (standardized path coefficient = 0.504, p \u3c.001) and social support (standardized path coefficient = 0.199, p =.010). In addition, sun protection behavior was indirectly predicted (through self-efficacy) by social support (standardized indirect effect = 0.160, p \u3c.001) and attitudes (standardized indirect effect = 0.192, p =.001). The explained variances for self-efficacy and sun protection behaviors were 43% and 35.4%, respectively. In conclusion, the IMB model appears to be a useful theoretical framework for predicting sun protection behaviors among patients with NMSC. Sun safety intervention programs should be developed based on this theoretical model for patients with NMSC