Latinas with abnormal breast findings: patient predictors of timely diagnostic resolution.

Background: Incomplete or delayed diagnostic resolution of breast abnormalities suspicious for cancer may contribute to poor breast cancer outcomes among ethnic minority women. We examine the effects of socioeconomic characteristics, knowledge, barriers to healthcare, communication, and clinical variables on diagnostic resolution in Latina women with breast abnormalities at two Los Angeles County public hospitals.

Methods: We analyzed telephone survey data for 714 women.

Characterization of baseline intestinal mucosal indices of injury and inflammation in men for use in rectal microbicide trials (HIV Prevention Trials Network-056).

Objectives: The purpose of this study was to evaluate the biologic stability of mucosal parameters that might be used as endpoints in phase 1 rectal safety studies.

Methods: Sixteen male participants were enrolled into 4 groups defined by HIV status, viral load, and sexual activity. Each participant underwent 3 flexible sigmoidoscopies at 2-week intervals with collection of blood, intestinal biopsies, and rectal secretions.

Development of a decision aid to address racial disparities in utilization of knee replacement surgery.

Objective: Previous studies suggest that poorer knowledge and expectations about surgical outcomes may be responsible for low rates of total knee replacement (TKR) among African American males. The goal of this study was to pilot test the scope, acceptability, and efficacy of an educational videotape and tailored TKR decision aid designed to reduce disparities in TKR knowledge and expectations.

Methods: African American and Caucasian male veteran volunteers ages 55-85 years with moderate to severe knee osteoarthritis (OA) were recruited.

Low-income women with breast abnormalities: system predictors of timely diagnostic resolution.

Background: Incomplete or delayed diagnostic resolution of breast abnormalities suspicious for cancer may contribute to poor breast cancer outcomes. We examine system predictors of timely diagnostic resolution in low-income, mostly Latina women with breast abnormalities at two Los Angeles County public hospitals.

Methods: We collected medical record data on 1,671 women.

Impact of the Medicare Short Stay Transfer Policy on patients undergoing major orthopedic surgery.

Objective: To examine the impact of the Short Stay Transfer Policy (SSTP) on practice patterns.

Data Sources: This study uses data from the Centers for Medicare and Medicaid Services Medicare Provider Analysis and Review (MEDPAR) file, Home Health Standard Analytical File, 1999 Provider of Service file, and data from the 2000 United States Census.

Study Design: An interrupted time-series analysis was used to examine the length of stay (LOS) and probability of "early" discharge to post acute care (PAC).

The contribution of specific causes of death to sex differences in mortality.

Objective: Men have higher mortality rates than women for most causes of death. This study was conducted to determine the contribution of specific causes of death to the sex difference in years of potential life lost (YPLL).

Methods: The authors examined data from the National Health Interview Survey with linked mortality data through 1997.

Lack of decay of HIV-1 in gut-associated lymphoid tissue reservoirs in maximally suppressed individuals.

Although peripheral blood mononuclear cells (PBMCs) and lymph nodes represent a principal reservoir, the contribution of gut-associated lymphoid tissue (GALT) has not been evaluated. In 15 HIV-1-infected subjects with maximal suppression of HIV replication by highly active antiretroviral therapy, we quantified HIV-1 DNA and RNA in mucosal biopsy specimens, PBMCs, and plasma with ultrasensitive assays. We also calculated compartmental burdens of HIV-1 DNA-positive cells and characterized the temporal decay of these reservoirs in a period of 1 year (with projections to >50 years).

Elevated serum soluble CD30 precedes the development of AIDS-associated non-Hodgkin's B cell lymphoma.

CD30, first described as the Ki antigen on malignant B cells in Hodgkin's lymphoma, is also expressed on normal activated B and T cells. It can be cleaved from the cell surface and detected in normal serum as soluble CD30 (sCD30), where it can be an indicator of levels of immune activation. In a cross-sectional study utilizing archived sera at a time point close to but preceding a diagnosis of acquired immunodeficiency syndrome (AIDS)-associated non-Hodgkin's B cell lymphoma, AIDS lymphoma subjects (n = 49) showed elevated mean levels of sCD30 compared to controls with AIDS but no malignancy (n = 44, p < 0.

Interferon-gamma decreases replication of primary R5 HIV-1 isolates in thymocytes.

As interferon-gamma (IFN-gamma) is produced at lower levels by neonatal than adult T cells, we determined whether IFN-gamma influences HIV-1 replication in thymocytes. IFN-gamma significantly decreased replication of R5 but not X4 viruses, and reduced depletion of CD3(hi)CD27 (mature) thymocytes, the preferential targets for R5 HIV-1. Thus infection and depletion of functionally mature thymocytes that can produce endogenous IFN-gamma may mutually contribute to HIV-1 replication in the thymus and to reduced T-cell output.

Serum levels of the homeostatic B cell chemokine, CXCL13, are elevated during HIV infection.

HIV infection is associated with B cell dysfunction, which includes B cell hyperactivation, hypergammaglobulinemia, impaired production of antibodies against specific antigens, and a loss of B cell memory. Because lymph node architecture is progressively destroyed during HIV infection, it is possible that normal B cell trafficking is impaired as well, which could be a cause or a result of these abnormalities. Because the homeostatic chemokine, CXCL13 (BLC, BCA-1), is a major regulator of B cell trafficking, we assessed circulating levels of this molecule in HIV infection.

Posttraumatic vasospasm: the epidemiology, severity, and time course of an underestimated phenomenon: a prospective study performed in 299 patients.

Object: The purpose of this prospective study was to evaluate the cumulative incidence, duration, and time course of cerebral vasospasm after traumatic brain injury (TBI) in a cohort of 299 patients.

Methods: Transcranial Doppler (TCD) ultrasonography studies of blood flow velocity in the middle cerebral and basilar arteries (VMCA and VBA, respectively) were performed at regular intervals during the first 2 weeks posttrauma in association with 133Xe cerebral blood flow (CBF) measurements. According to current definitions of vasospasm, five different criteria were used to classify the patients: A (VMCA > 120 cm/second); B (VMCA > 120 cm/second and a Lindegaard ratio [LR] > 3); C (spasm index [SI] in the anterior circulation > 3.

Differences in cause-specific mortality between Latino and white adults.

Background: Understanding differences in cause-specific mortality between Latinos and whites is important for targeting future public health interventions and research aimed at eliminating health disparities.

Objectives: We sought to determine the contribution of specific causes of death to Latino-white differences in mortality.

Research Design: Using nationally representative data, we estimated cause-specific mortality risks, which were then used in a simulation model to estimate mortality events for a cohort of persons starting at age 25 and followed until death or age 75.

Imputation and variable selection in linear regression models with missing covariates.

Across multiply imputed data sets, variable selection methods such as stepwise regression and other criterion-based strategies that include or exclude particular variables typically result in models with different selected predictors, thus presenting a problem for combining the results from separate complete-data analyses. Here, drawing on a Bayesian framework, we propose two alternative strategies to address the problem of choosing among linear regression models when there are missing covariates. One approach, which we call "impute, then select" (ITS) involves initially performing multiple imputation and then applying Bayesian variable selection to the multiply imputed data sets.

Risk stratification for in-hospital mortality in acutely decompensated heart failure: classification and regression tree analysis.

Context: Estimation of mortality risk in patients hospitalized with acute decompensated heart failure (ADHF) may help clinicians guide care.

Objective: To develop a practical user-friendly bedside tool for risk stratification for patients hospitalized with ADHF.

Design, Setting, And Patients: The Acute Decompensated Heart Failure National Registry (ADHERE) of patients hospitalized with a primary diagnosis of ADHF in 263 hospitals in the United States was queried with analysis of patient data to develop a risk stratification model.

Relationship between valve opening pressure, body position, and intracranial pressure in normal pressure hydrocephalus: paradigm for selection of programmable valve pressure setting.

Objective: There is little scientific basis for guidance in selecting the optimal valve for the treatment of normal pressure hydrocephalus. The aim of this study was to determine the programmable valve opening pressure setting that would result in a slight reduction in intracranial pressure (ICP) after a ventriculoperitoneal shunt is implanted. We also assessed whether shunt-induced ICP could be predicted on the basis of a simple hydrodynamic equation.

Non-Hodgkin's B cell lymphoma in persons with acquired immunodeficiency syndrome is associated with increased serum levels of IL10, or the IL10 promoter -592 C/C genotype.

Interleukin-10 (IL10) may contribute to the development of non-Hodgkin's B cell lymphoma, especially in the context of acquired immunodeficiency syndrome (AIDS), where lymphoma incidence is greatly increased. Utilizing specimens from the Multicenter AIDS Cohort Study (MACS) obtained prior to diagnosis of AIDS-associated lymphoma, detectable serum human IL10 was seen much more frequently in lymphoma cases (n = 61, 26%) compared to CD4-matched AIDS controls (5%, P = 0.004), or to HIV-infected (2%, P = 0.

Ethnic differences in birth weight by gestational age: at least a partial explanation for the Hispanic epidemiologic paradox?

Objective: The purpose of this study was to evaluate ethnic differences in low birth weight and gestational age-dependent birth weight.

Study Design: A retrospective cohort study of 47,669 newborn infants was conducted with the use of the perinatal database of the Memorial Health Care System. Logistic regression was used to estimate the odds ratio for low birth weight by ethnic group, which took into account gestational age at delivery.

Energy dysfunction as a predictor of outcome after moderate or severe head injury: indices of oxygen, glucose, and lactate metabolism.

Unlabelled: The purpose of this study was to determine if the relationship between abnormalities in glucose, lactate, and oxygen metabolism were predictive of neurologic outcome after moderate or severe head injury, relative to other known prognostic factors. Serial assessments of the cerebral metabolic rates for glucose, lactate, and oxygen were performed using a modified Kety-Schmidt method. In total, 31 normal control subjects were studied once, and 49 TBI patients (mean age 36+/-16 years, median GCS 7) were studied five times median per patient from postinjury days 0 to 9.

Expression and function of CD28 on Epstein-Barr virus-positive B cell lines and AIDS-associated non-Hodgkin's lymphoma cell lines.

CD28, which is expressed on most T cells, can provide a costimulatory signal during T cell activation. Although principally considered to be a T cell-associated molecule, CD28 has been seen to be expressed on mast cells and natural killer cells, as well as on plasma and myeloma cells, but not on cells representing earlier stages of B cell development. Here were report that CD28 was expressed on Epstein-Barr virus (EBV)-positive B lymphoblastoid and AIDS-associated non-Hodgkin's lymphoma cell lines.

Efficacy of hyperventilation, blood pressure elevation, and metabolic suppression therapy in controlling intracranial pressure after head injury.

Object: Hyperventilation therapy, blood pressure augmentation, and metabolic suppression therapy are often used to reduce intracranial pressure (ICP) and improve cerebral perfusion pressure (CPP) in intubated head-injured patients. In this study, as part of routine vasoreactivity testing, these three therapies were assessed in their effectiveness in reducing ICP.

Methods: Thirty-three patients with a mean age of 33 +/- 13 years and a median Glasgow Coma Scale (GCS) score of 7 underwent a total of 70 vasoreactivity testing sessions from postinjury Days 0 to 13.

Contribution of major diseases to disparities in mortality.

Background: Mortality from all causes is higher for persons with fewer years of education and for blacks, but it is unknown which diseases contribute most to these disparities.

Methods: We estimated cause-specific risks of death from data from the National Health Interview Survey conducted from 1986 through 1994 and from linked vital statistics. Using these risk estimates, we calculated potential years of life lost and potential gains in life expectancy related to specific causes, with stratification according to education level and race.

Immunologic profile of highly exposed yet HIV type 1-seronegative men.

The host immune factors that determine susceptibility to HIV-1 infection are poorly understood. We compared multiple immunologic parameters in three groups of HIV-1-seronegative men: 14 highly exposed (HR10), 7 previously reported possibly to have sustained transient infection (PTI), and a control group of 14 low risk blood bank donors (BB). Virus-specific cellular immune assays were performed for CD4(+) T helper cell responses, CD8(+) cytotoxic T lymphocyte activity, CD8(+) cell chemokine release, and CD8(+) cell-derived antiviral soluble factor activity.

Early and persistent impaired percent alpha variability on continuous electroencephalography monitoring as predictive of poor outcome after traumatic brain injury.

Object: Early prediction of outcomes in patients after they suffer traumatic brain injury (TBI) is often nonspecific and based on initial imaging and clinical findings alone, without direct physiological testing. Improved outcome prediction is desirable for ethical, social, and financial reasons. The goal of this study was to determine the usefulness of continuous electroencephalography (EEG) monitoring in determining prognosis early after TBI, while the patient is in the intensive care unit.

Impact of cytokines on replication in the thymus of primary human immunodeficiency virus type 1 isolates from infants.

Early infection of the thymus with the human immunodeficiency virus (HIV) may explain the more rapid disease progression among children infected in utero than in children infected intrapartum. Therefore, we analyzed infection of thymocytes in vitro by HIV type 1 primary isolates, obtained at or near birth, from 10 children with different disease outcomes. HIV isolates able to replicate in the thymus and impact thymopoiesis were present in all infants, regardless of the timing of viral transmission and the rate of disease progression.