A multifactorial role for P. falciparum malaria in endemic Burkitt's lymphoma pathogenesis.

Endemic Burkitt's lymphoma (eBL) arises from the germinal center (GC). It is a common tumor of young children in tropical Africa and its occurrence is closely linked geographically with the incidence of P. falciparum malaria.

Cigarette smoke worsens lung inflammation and impairs resolution of influenza infection in mice.

Background: Cigarette smoke has both pro-inflammatory and immunosuppressive effects. Both active and passive cigarette smoke exposure are linked to an increased incidence and severity of respiratory virus infections, but underlying mechanisms are not well defined. We hypothesized, based on prior gene expression profiling studies, that upregulation of pro-inflammatory mediators by short term smoke exposure would be protective against a subsequent influenza infection.

A virtual look at Epstein-Barr virus infection: simulation mechanism.

Epstein-Barr virus (EBV) is an important human pathogen that establishes a life-long persistent infection and for which no precise animal model exists. In this paper, we describe in detail an agent-based model and computer simulation of EBV infection. Agents representing EBV and sets of B and T lymphocytes move and interact on a three-dimensional grid approximating Waldeyer's ring, together with abstract compartments for lymph and blood.

Epstein-Barr virus: a paradigm for persistent infection - for real and in virtual reality.

The really interesting thing about herpesviruses is that they can establish lifelong persistant infections in immunocompetent hosts. At first glance, they would seem to have very different ways of doing this. Here we will use as a model our current understanding of how the human herpesvirus Epstein-Barr virus establishes and maintains such an infection.

Using formal concept analysis for microarray data comparison.

Microarray technologies, which can measure tens of thousands of gene expression values simultaneously in a single experiment, have become a common research method for biomedical researchers. Computational tools to analyze microarray data for biological discovery are needed. In this paper, we investigate the feasibility of using formal concept analysis (FCA) as a tool for microarray data analysis.

A virtual look at Epstein-Barr virus infection: biological interpretations.

The possibility of using computer simulation and mathematical modeling to gain insight into biological and other complex systems is receiving increased attention. However, it is as yet unclear to what extent these techniques will provide useful biological insights or even what the best approach is. Epstein-Barr virus (EBV) provides a good candidate to address these issues.

Simulating Epstein-Barr virus infection with C-ImmSim.

Motivation: Epstein-Barr virus (EBV) infects greater than 90% of humans benignly for life but can be associated with tumors. It is a uniquely human pathogen that is amenable to quantitative analysis; however, there is no applicable animal model. Computer models may provide a virtual environment to perform experiments not possible in human volunteers.

An insight-based longitudinal study of visual analytics.

Visualization tools are typically evaluated in controlled studies that observe the short-term usage of these tools by participants on preselected data sets and benchmark tasks. Though such studies provide useful suggestions, they miss the long-term usage of the tools. A longitudinal study of a bioinformatics data set analysis is reported here.

Weight loss in overweight patients maintained on atypical antipsychotic agents.

Background: Weight gain and associated medical morbidity offset the reduction of extrapyramidal side effects associated with atypical antipsychotics. Efforts to control weight in antipsychotic-treated patients have yielded limited success.

Methods: We studied the impact of an intensive 24-week program of diet, exercise, and counseling in 17 chronically psychotic patients (10 women, seven men) who entered at high average body weight (105.

An insight-based methodology for evaluating bioinformatics visualizations.

High-throughput experiments, such as gene expression microarrays in the life sciences, result in very large data sets. In response, a wide variety of visualization tools have been created to facilitate data analysis. A primary purpose of these tools is to provide biologically relevant insight into the data.

Arrested spread of vesicular stomatitis virus infections in vitro depends on interferon-mediated antiviral activity.

A quantitative understanding of the innate immune response will enable its recruitment against emerging, poorly characterized, or weaponized viral pathogens. To gain insights into how the innate responses can limit viral spread, we used quantitative focal infections to study how the spread of recombinant vesicular stomatitis viruses (VSV) on baby hamster kidney (BHK) and delayed brain tumor (DBT) cell monolayers is affected by innate cellular antiviral responses. We observed that rates of infection spread correlated with one-step growth rankings for four ectopic VSV strains: N1, N2, N3, and N4.

Propagation of viruses on micropatterned host cells.

We have developed a technique to characterize the in vitro propagation of viruses. Microcontact printing was used to generate linear arrays of alkanethiols on gold surfaces, which served as substrates for the patterned culture of baby hamster kidney (BHK-21) cells. Vesicular stomatitis virus (VSV) was added to unpatterned cell reservoirs adjacent to the patterned cells and incubated, setting in motion a continuously advancing viral infection into the patterned cells.

The effect of a novel dietary intervention on weight loss in psychotropic drug-induced obesity.

Weight gain associated with the use of psychotropic drugs may be related to their blockade of serotonin receptors which mediate satiety. Obese individuals whose weight gain followed psychotropic drug use, or control nondrug-treated obese subjects, were treated with a 12-week weight loss program that included a carbohydrate-rich, protein-poor beverage thought to increase brain serotonin.The 38 psychotropic drug treated females lost slightly more weight than their 60 nondrug-treated controls, ie, 13.

Quantifying viral propagation in vitro: toward a method for characterization of complex phenotypes.

For a eukaryotic virus to successfully infect and propagate in cultured cells several events must occur: the virion must identify and bind to its cellular receptor, become internalized, uncoat, synthesize viral proteins, replicate its genome, assemble progeny virions, and exit the host cell. While these events are taking place, intrinsic host defenses activate in order to defeat the virus, e.g.

Nuclear clustering in myotubes: a proposed role in acetylcholine receptor mRNA expression.

We investigated the functional relationship between nuclear topology, as expressed by degree and type of nuclear aggregation, and appearance of acetylcholine receptor (AChR) subunit mRNAs. Embryonic chick muscle cell cultures treated with the muscle activity blocking agents decamethonium (DCM), d-tubocurare (TBC), and tetrodotoxin (TTX) or co-cultured with cholinergic neurons were examined for the influence of muscle activity on nuclear aggregation and its effects on AChR alpha-, gamma-, and delta-subunit message expression. mRNA was measured by in situ hybridization and nuclei were visualized by bis-benzimide DNA staining.

Ion-water and water-water interactions in a gramicidinlike channel: effects due to group polarizability and backbone flexibility.

In the gramicidin channel, ionic transport and water transport occur simultaneously. Gramicidin's transport properties are influenced by ionic interactions with both the polypeptide and the channel waters. We present results of molecular dynamics studies on a series of alkali metal ions interacting with a water-filled gramicidinlike channel (a configurationally constrained polyglycine analog) at the dimer junction, in mid-monomer, and near the channel entrance.

A novel in situ double-labeling method for simultaneous detection of mRNA and expressed protein or two different mRNAs.

We have developed a novel double-labeling method to investigate multiple gene expression in single cells. The method relies on the use of a radioactive probe followed by a colorimetric probe. Unique to this method, the radioactive signal is first captured on an emulsion pre-coated slide, which totally separates it from the process of color development and prevents any interference with the radiolabeled probe.

Enkephalins stimulate leukemia cell migration and surface expression of CD9.

Opioid peptides have been implicated in the regulation of tumor growth and biology; however, little attention has been given to the mechanisms that are involved. In this study we show that physiological concentrations of the endogenous opioid neuropeptide methionine-enkephalin (MET-ENK) and the synthetic enkephalins D-Ala2, Me-Phe4, Gly(ol)5 and D-Ala2, D-Leu5 are stimulants for the in vitro migration of pre-B acute lymphoblastoid leukemia (ALL) cells. Activation of the human pre-B ALL cell lines NALM 6 and LAZ 221 with MET-ENK resulted in both an increase in their migration and an augmentation in the surface expression of the leukemia cell marker CD9.

Effect of ventilation on acid-base balance and oxygenation in low blood-flow states.

Objectives: To investigate how minute ventilation affects the partial pressure of end-tidal CO2 and arterial and mixed venous pH, PCO2, PO2, and the concentration of bicarbonate during low blood-flow states. We tested the null hypothesis that acid-base conditions during low rates of blood flow are not significantly different when minute ventilation is doubled or halved.

Design: Prospective, experimental, animal study.

End-tidal carbon dioxide during extremely low cardiac output.

Study Objective: A number of studies have shown that expired CO2 concentration is closely related to cardiac output, but that cardiac output was not controlled as an independent variable. In addition, the partial pressure of end-tidal CO2 (PETCO2) during extremely low cardiac output has not been reported. The objective of the present study was to measure PETCO2 during well-controlled, very low blood flow rates under conditions of constant minute ventilation.

Gonadotropin-releasing hormone-induced stimulation and desensitization of free alpha-subunit secretion mirrors luteinizing hormone and follicle-stimulating hormone in perifused rat pituitary cells.

A pulsatile pattern of hypothalamic GnRH stimulation is necessary for the maintenance of pituitary LH and FSH secretion, with continuous GnRH leading to a decrement in response. Although the physiological pattern of free alpha-subunit secretion closely mimics that of LH, several reports have indicated that free alpha-subunit is not desensitized by continuous GnRH stimulation. To explore the basis of this phenomenon, we have evaluated the responses of all three gonadotrope secretory products to carefully coordinated administration of pulsatile and continuous GnRH in a dispersed rat pituitary perifusion system.