Administration of an antibody to E-selectin in patients with septic shock

OBJECTIVES

To determine the safety and pharmacokinetics of a murine monoclonal antibody to E-selectin in patients with newly developed septic shock.

DESIGN

Open-label, prospective, phase II pilot study with escalating doses of the antibody.

SETTING

Intensive care unit of a 900-bed university hospital.

PATIENTS

Nine patients who survived the first 24 hrs of septic shock.

INTERVENTIONS

In addition to standard therapy, an intravenous bolus of a murine monoclonal antibody to E-selectin, CY1787, was given at doses of 0.1 mg/kg (n = 3), 0.33 mg/kg (n = 3), and 1.0 mg/kg (n = 3).

MEASUREMENTS AND MAIN RESULTS

CY1787 was well tolerated in all patients. Signs of shock resolved in all patients, and organ failure entirely reversed in eight patients. All patients survived the 28-day follow-up. Administration of CY1787 was associated with an early and brisk increase in PaO2/FIO2 ratio (p < .001), from 146 +/- 38 mm Hg (19.5 +/- 5.1 kPa) to 205 +/- 45 mm Hg (27.3 +/- 6.0 kPa) after 2 hrs, and 250 +/- 58 mm Hg (33.3 +/- 7.7 kPa) after 12 hrs. A dose-related effect of CY1787 was suggested by an earlier weaning from catecholamine therapy and a faster resolution of organ failure in the high-dose group. Development of antimouse antibodies was documented in eight patients.

CONCLUSIONS

This pilot study indicates that this antibody to E-selectin appears to be safe and may represent a promising form of therapy in septic shock.

Quantitative culture of HIV-1 from bronchoalveolar lavage cells

Determination of the infectious virus burden at the organ level is critical for understanding the pathophysiology of human immunodeficiency virus type 1 (HIV-1) infection. To evaluate the burden of HIV-1 in the lung, quantitative cultures were performed on bronchoalveolar lavage (BAL) cells from 11 HIV-1 seropositive subjects without respiratory infections and compared with peripheral blood mononuclear cells (PBMC) obtained from the same subjects. Fifty percent (50%) of subjects had positive BAL cell cultures while 82% had positive PBMC cultures. There was much less virus cultured from BAL cells than from PBMCs, whether using phytohemagglutinin (PHA)-stimulated peripheral blood lymphocyte (PBL) targets (p < 0.05) or adherent monocyte targets (p < 0.02). There was no significant difference between the HIV-1 titers obtained for BAL cells whether using PHA-stimulated PBL or adherent monocyte targets (p = 0.13). These studies demonstrate that BAL cell cultures for HIV-1 in subjects without respiratory infections are less frequently positive than PBMC cultures, that less virus can be recovered from BAL cells than from PBMC, and that HIV-1 isolates from BAL cells replicate in both PHA-stimulated PBL targets and adherent monocyte targets. Quantitative assessment of virus burden in the lung is important for future studies of HIV-1 pathogenesis and for evaluating potential antiretroviral therapies aimed at altering the natural history of organ dysfunction associated with retroviral replication.

Use of personal characteristics in the selection of astronauts

Which personal characteristics are used in selecting astronauts? We decided to examine this question using National Aeronautics and Space Administration (NASA) archival data collected on 2288 applicants. Undergraduate grade point average, graduate grade point average, and several facets of aviation experience were the best predictors of who was interviewed and then selected to be an astronaut. Adjustments were made to insure that a sufficient number of women and minority group members were selected, while still maintaining high selection standards. The selection process seems well-designed, and follows explicit NASA guidelines. We suggest simplifying the selection process by using a single discriminant function as an interview and/or selection criterion.

Phytosterols are present in Pneumocystis carinii

Although originally classified as a protozoan, Pneumocystis carinii is now considered to have fungal characteristics. Drugs typically used for the treatment of fungal infections target ergosterol. Because P. carinii is an important pathogen in AIDS and other immunocompromised patients, knowledge of the sterol content of this organism may be useful as a basis for developing new treatment strategies or for improving diagnosis. P. carinii organisms were harvested from infected rat lungs and were purified by filtration. Control preparations from uninfected animals were identically prepared. Lipids were extracted from the organisms and control preparations and were separated into neutral lipid, glycolipid, and phospholipid fractions by silicic acid chromatography. The neutral lipid fraction was further treated by alkaline hydrolysis and was analyzed by reversed-phase high-pressure liquid chromatography (HPLC), gas chromatography (GC), and GC-mass spectrometry (GC-MS). As shown by HPLC, the neutral lipid fraction from infected rats contained a minimum of six peaks, while in control preparations a single peak with a retention time identical to that of cholesterol was observed. The predominant sterol in these preparations was positively identified by GC-MS as cholesterol and constituted 80 to 90% of the total. The remaining peaks had relative retention times similar to those of phytosterols by both HPLC and GC, and the similarity of these sterols to those derived from plants and fungi was confirmed by MS. Ergosterol, however, was not present. These results provide further evidence for a close phylogenetic relationship between P. carinii and fungi and suggest that these sterols could be used as targets for drug development and for improving diagnosis.

Resonance in a model of a mammalian neuron

In this paper we show that for a small range of voltages the model described in the previous paper (Hindmarsh & Rose Phil. Trans. R. Soc. Lond. B 346, 129-150 (1994a)) will generate damped oscillations in response to a negative current pulse. As a consequence the cell has the property that it can be driven into bursting by periodic sinusoidal inputs close to the resonant frequency. The main objective of this paper is to analyse this resonant behaviour using the model of the model introduced in the previous paper. We derive analytical expressions which closely approximate the nonlinear resonance observed in the physiological model driven by a periodic sinusoidal input. This leads to the conclusion that resonance could play a role in synaptic transmission at relay nuclei in the mammalian brain.

A model for rebound bursting in mammalian neurons

In this paper we begin by simplifying our previous model of a thalamic neuron (Rose & Hindmarsh Proc. R. Soc. Lond. B 237, 289-312 (1989b)) by removal of the A current. A Ca(2+)-activated K+ current, with Ca2+ entering through T channels, is then added to give a model for a class of mammalian neurons in which the membrane potential oscillates in the subthreshold region following a hyperpolarizing current step. The properties of the model are represented using an experimentally observable bifurcation diagram. In the subthreshold region only three variables are required to explain the essential dynamic properties of the cell. In this three-dimensional space the solutions tend to lie on a surface which resembles a paraboloid. We use a simplified model of this model to explain both the dynamics of the solutions on this surface and the form of the bifurcation diagram.

A model of intrinsic and driven spindling in thalamocortical neurons

We add a slow hyperpolarization-activated inward current IH = gHmH (v-vH) to our previous model of rebound bursting (Hindmarsh & Rose Phil. Trans. R. Soc. Lond. B 346, 129-150 (1994a)) to give a four-dimensional physiological model, and a corresponding four-dimensional model of the model. The physiological model generates periodic 'bursts of bursts' or 'spindles' resembling those recorded experimentally in thalamocortical (TC) neurons. The model of the model is simplified to a two-dimensional system having a limit cycle which corresponds to the slow spindle oscillation of the physiological model. Analysis of the stability of this two-dimensional model allows us to divide the parameter space of the slope (gamma mH) and shift (theta mH) parameters of mH infinity (v) into regions in which the model generates spindles or continuous bursting. This enables us to determine the parameter values required for spindling in the physiological model and to explain the experimentally observed effects of noradrenaline. Next we examine whether a cell at a stable equilibrium point can be driven into spindling by applying a sinusoidal input at the resonant frequency. This is done by averaging the equations for the driven model of the model. Analysis of the stability of these averaged equations shows how the regions of the (theta mH, gamma mH) parameter space change when the system is driven by a sinusoidal input. This enables us to choose parameter values for a physiological model of a driven spindle. We show that if the physiological model is modified to include a voltage-dependent time constant for mH, spindles, similar to those of TC cells, can be obtained with a small Ca(2+)-activated K+ current. Finally our knowledge of the form of the bifurcation diagram and the conditions for resonance leads to a new suggestion for the roles of GABAA and GABAB inhibitory postsynaptic potentials when TC cells are driven into spindling by neurons of the nucleus reticularis thalami.

Predicting astronaut effectiveness: a multivariate approach

In this study, measures of astronaut effectiveness were administered to volunteers from the astronaut corps in order to validate psychological "select-in" criteria for long-duration space missions. Using a peer nomination format, astronauts rated their peers with whom they had either flown or trained. Factor analysis revealed two latent performance dimensions: job competence and group living. The job competence dimension measured the instrumental aspects relating to job knowledge and job performance. The group living dimension measured the interpersonal aspects relating to teamwork and desirability as a colleague on Space Station. Analyses revealed that the personality variables could explain a significant proportion of the variance in the group living performance dimension, but not the job competence performance dimension. The findings are not surprising since astronauts are highly screened on the basis of past attainment, but are not as highly screened on aspects relating to teamwork and interpersonal concerns.

Psychological predictors of astronaut effectiveness

Are the personality characteristics of astronauts related to their professional effectiveness? In order to answer this question, effectiveness and personality data were collected from 65 NASA astronauts. Several findings emerged from these data. Five personality subscales were related to effectiveness in one form or another. They were: high Negative Expressivity and Negative Communion (subordinate and gullible), low Impatience and Irritability, low Openness (to new ideas and experiences), low Negative Instrumentality (egoism) and high Agreeableness. Examining the graphs of these relationships indicated that they were not linear. This examination indicated that high levels on these undesirable personality characteristics (e.g., Impatience/Irritability) were distributed across all levels of effectiveness. Low levels of the undesirable personality characteristics were found only among the most effective astronauts. We concluded that these other-directed personality qualities will assume increasing importance in long-term spaceflight, and consequently, should be the focus of greater attention in future astronaut selection and training.

Abnormal lipid composition of bronchoalveolar lavage fluid obtained from individuals with AIDS-related lung disease

Surfactant lipids are not only important to the physiologic function of the lungs, but may also influence disease processes like Pneumocystis pneumonia, in which the interaction of host-defense cells with pathogen occurs within the confines of the surfactant-rich alveolar hypophase. In the present studies the lipid profile of bronchoalveolar lavage fluid (BALF) was characterized in subjects with AIDS-related lung diseases including Pneumocystis pneumonia. BALF lipid and total protein measurements were made in 43 subjects with acquired immune deficiency syndrome (AIDS)-related lung disease and compared with those made in 50 normal human immunodeficiency virus (HIV)-seronegative controls. The AIDS patient samples contained significantly greater amounts of total cholesterol, phosphatidylglycerol (PG), and protein than the control samples; in contrast to previous observations in rodent P. carinii infection, no differences were seen in total phospholipid (PL) or phosphatidylcholine (PC) in the two groups. The proportions of several of these lipids were deranged in BALF obtained from the patient group: PG/PL and PC/cholesterol differed significantly from normal samples. In the subset of patients with AIDS-related Pneumocystis pneumonia, no correlation was apparent between discrete BALF lipids and clinical indices reflective of disease severity. Using these measurements to approximate the lipid composition of the alveolar microenvironment in AIDS-related lung disease, we performed experiments in which normal human alveolar macrophages were exposed to exogenous liposomal lipids and then challenged with P. carinii. The ingestion but not binding of P. carinii by macrophages was diminished as a result of lipid exposure.(ABSTRACT TRUNCATED AT 250 WORDS)

Human immunodeficiency virus type 1 infection of human macrophages modulates the cytokine response to Pneumocystis carinii

The present studies examined production of the cytokines tumor necrosis factor alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and IL-6 by human monocyte-derived macrophages exposed to Pneumocystis carinii in vitro and the impact of concurrent macrophage infection with human immunodeficiency virus type 1 (HIV-1) on these cytokine responses. Macrophages were infected with the HIV-1 BaL monocytotropic strain for 10 to 14 days and then exposed to P. carinii. At various times following P. carinii treatment, culture supernatants were harvested to assess the cytokine profile. Addition of P. carinii to HIV-uninfected macrophages resulted in augmented production of IL-6, TNF-alpha, and IL-1 beta protein. By contrast, in HIV-infected macrophages exposed to P. carinii, only the release of IL-6 was increased compared with that for HIV-uninfected macrophages, while the levels of TNF-alpha and IL-1 beta decreased. This altered response was confirmed at the molecular level for TNF-alpha mRNA. Preventing physical contact between P. carinii and macrophages by a membrane filter inhibited all cytokine release. Substituting P. carinii with a preparation of P. carinii 95- to 115-kDa major membrane glycoprotein A yielded a response similar to that obtained by addition of intact P. carinii. These results suggest that HIV-1 infection of human macrophages modulates cytokine responses to P. carinii.

Long-term performance and wear of ultrahigh-molecular-weight polyethylene in total joint replacement prostheses: a brief overview and perspective

Ultrahigh-molecular-weight polyethylene (UHMWPE) is used extensively in total joint replacements, particularly in hip and knee joints. At present, there is extensive concern with the long-term consequences of wear of this material, specifically osteolytic reactions to wear debris. The relationship of wear behavior to polymer morphology is almost completely unknown. Information on the effects of radiation sterilization on crystallinity is available, but gross conflicts exist. A central problem is the release, over long time periods, of huge numbers of submicron particles by wear. It has not been generally recognized that short-term, severe wear and long-term wear of UHMWPE in total joint replacements are very different in character and results. When the long-term wear regime is correctly defined, it is clear that knowledge of the influence of structure and properties on this specific phenomenon is almost completely absent.

Assessments of astronaut effectiveness

This study examined the reliability and convergent validity of three methods of peer and supervisory ratings of the effectiveness of individual NASA astronauts and their relationships with flight assignments. These two techniques were found to be reliable and relatively convergent. Seniority and a peer-rated Performance and Competence factor proved to be most closely associated with flight assignments, while supervisor ratings and a peer-rated Group Living and Personality factor were found to be unrelated. Results have implications for the selection and training of astronauts.

Concurrent infection of human macrophages with HIV-1 and Mycobacterium avium results in decreased cell viability, increased M. avium multiplication and altered cytokine production

The effects of a concurrent HIV-1 and Mycobacterium avium infection in vitro were assessed in human peripheral blood-derived macrophages (M phi). M phi were infected with HIV-1Ba-L strain for 14 days then infected with M. avium (HIV/M. avium) or treated with LPS (HIV/LPS). At various times after M. avium or LPS treatment, Mo phi cultures were harvested for quantitation of HIV and M. avium replication, as well as M phi cellular viability. In addition, mRNA and supernatants were collected for assessment of induction of the cytokines TNF-alpha, IL-1 beta and IL-6. M. avium multiplication was greater in HIV-infected M phi, whereas no difference in virus production, based on p24 and RT values, was observed between HIV-infected cells and HIV/M. avium or HIV/LPS M phi. M. avium infection of HIV-1-infected M phi also caused a decrease in viability of the M phi. HIV-1/M. avium-infected M phi had a 24 h delay in induction of TNF-alpha steady state mRNA when compared with HIV/LPS or M. avium only or LPS-only treated M phi. HIV infection also increased the amount and the length of induction of IL-1 beta and IL-6 steady state mRNA stimulated by either M. avium or LPS. In addition, prolonged and increased protein production of TNF-alpha, IL-6, and IL-1 beta was observed in HIV/M. avium-infected cells when compared with the other treatments. In direct contrast to M. avium infection, no significant differences in LPS-induced protein production of the three cytokines was observed between HIV-1-infected and -noninfected M phi. Treatment of HIV/M. avium-infected cells with human rGM-CSF did not increase either the time or quantity of induction of TNF-alpha mRNA or protein production in HIV/M. avium-infected M phi. The increase in M. avium numbers, dysregulation of cytokine production, and subsequent cell death seen in vitro in HIV/M. avium-infected human M phi may reflect part of the underlying cause of the highly disseminated M. avium disease pattern observed in AIDS patients.

Concurrent infection of human macrophages with HIV-1 and Mycobacterium avium results in decreased cell viability, increased M. avium multiplication and altered cytokine production

The effects of a concurrent HIV-1 and Mycobacterium avium infection in vitro were assessed in human peripheral blood-derived macrophages (M phi). M phi were infected with HIV-1Ba-L strain for 14 days then infected with M. avium (HIV/M. avium) or treated with LPS (HIV/LPS). At various times after M. avium or LPS treatment, Mo phi cultures were harvested for quantitation of HIV and M. avium replication, as well as M phi cellular viability. In addition, mRNA and supernatants were collected for assessment of induction of the cytokines TNF-alpha, IL-1 beta and IL-6. M. avium multiplication was greater in HIV-infected M phi, whereas no difference in virus production, based on p24 and RT values, was observed between HIV-infected cells and HIV/M. avium or HIV/LPS M phi. M. avium infection of HIV-1-infected M phi also caused a decrease in viability of the M phi. HIV-1/M. avium-infected M phi had a 24 h delay in induction of TNF-alpha steady state mRNA when compared with HIV/LPS or M. avium only or LPS-only treated M phi. HIV infection also increased the amount and the length of induction of IL-1 beta and IL-6 steady state mRNA stimulated by either M. avium or LPS. In addition, prolonged and increased protein production of TNF-alpha, IL-6, and IL-1 beta was observed in HIV/M. avium-infected cells when compared with the other treatments. In direct contrast to M. avium infection, no significant differences in LPS-induced protein production of the three cytokines was observed between HIV-1-infected and -noninfected M phi. Treatment of HIV/M. avium-infected cells with human rGM-CSF did not increase either the time or quantity of induction of TNF-alpha mRNA or protein production in HIV/M. avium-infected M phi. The increase in M. avium numbers, dysregulation of cytokine production, and subsequent cell death seen in vitro in HIV/M. avium-infected human M phi may reflect part of the underlying cause of the highly disseminated M. avium disease pattern observed in AIDS patients.

Definition of a responder: analysis of behavioral, cardiovascular, and endocrine responses to varied workload in air traffic controllers

Individual differences in behavioral, cardiovascular, and endocrine responses to varying workload among 381 air traffic controllers were assessed using random regression modeling. Although most men showed significant increases in behavioral arousal associated with increasing planes, there were major individual differences in response in systolic and diastolic blood pressure, heart rate, and cortisol. Approximately 20% to 25% of those studied had large increases in each of these domains, along with a smaller group showing inverse responses in heart rate and cortisol. There was also evidence of a smaller number of enhanced responders within the highest groups, who tended to have more missing values at higher levels of workload. There was convergence in the definition of responders using three statistical strategies: random regression, correlational analyses, and ANOVA. Response in one physiological/behavioral domain was essentially independent of response in another, supporting the conclusion of specificity, rather than a global tendency to respond to increasing work load.

Results of a structured psychiatric interview to evaluate NASA astronaut candidates

One hundred six astronaut applicants who had passed initial screening were evaluated for Axis I and Axis II DSM-III-R diagnoses using a structured psychiatric interview. Nine of 106 candidates (8.5%) met diagnostic criteria for six Axis I (including V-code), or Axis II disorders. The use of the NASA structured interview was effective in identifying past and present psychopathology in a group of highly motivated and healthy astronaut applicants. This was the first time that a structured interview had been used in such a setting for this purpose. The methodology described is applicable to any situation where the presence or history of psychopathology requires evaluation for job selection (e.g. pilot selection).

The effect of aerosolized recombinant human granulocyte macrophage colony-stimulating factor on lung leukocytes in nonhuman primates

The number and function of myeloid cells in the lungs are critical determinants of health and disease. To examine whether these cells can be modulated in vivo by a colony-stimulating factor (CSF), recombinant human granulocyte macrophage-CSF (GM-CSF) was given to cynomolgus monkeys by either continuous intravenous infusion (7,200 U/kg/day) for 2 wk or by aerosol exposure to 10(7) U on 1 or 2 consecutive days. At intervals after the initiation of GM-CSF administration, animals underwent bronchoalveolar lavage (BAL) and had peripheral blood sampled to characterize changes in lung and circulating phagocytic cells. Compared with animals exposed to bovine serum albumin, there was an increase in the total number of BAL cells retrieved. This increase was greatest in animals receiving aerosolized GM-CSF, and it was the result of more macrophages and neutrophils. Both lung macrophages and blood neutrophils from animals exposed to aerosolized GM-CSF exhibited an augmented respiratory burst in response to phorbol myristate acetate. Lung macrophages from GM-CSF-exposed animals exhibited increased capacity to bind and/or ingest opsonized and unopsonized Staphylococcus aureus. Despite functional activation of lung phagocytic cells, biochemical analyses of BAL fluid for markers of lung injury revealed an increase in only some parameters in the GM-CSF group. Intravenous administration of GM-CSF had the expected effect on augmenting the number of myeloid cells in the bloodstream. Aerosolized GM-CSF produced a transient effect on circulating myeloid cell number between 3 and 5 days after exposure.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of colony stimulating factor activity in the human respiratory tract. Comparison of healthy smokers and nonsmokers

The number and function of pulmonary macrophages are critical to lung homeostasis. To characterize factors normally present in the human respiratory tract that can influence these parameters, bronchoalveolar lavage (BAL) fluid obtained from healthy smokers and nonsmokers was assayed for the presence of colony-stimulating factor (CSF) activity. Concentrated BAL fluid from both populations was capable of inducing incorporation of [3H]thymidine by murine macrophages. The mean increase (+/- SEM) in incorporation over control cultures not exposed to BAL fluid was 0.98 +/- 0.22 for nonsmokers and 2.25 +/- 1.19 for smokers (p less than 0.001). This CSF bioactivity was characterized as macrophage-CSF (M-CSF) by virtue of its action on murine macrophages, the detection of M-CSF protein by a specific ELISA assay, and the inability to detect other macrophage-active CSFs, granulocyte macrophage-CSF (GM-CSF) and interleukin-3 (IL-3), in a proliferation assay employing the MO7E cell line. There was a significant correlation between macrophage number in BAL samples and measureable bioactivity among both smokers and nonsmokers (r = 0.763; p less than 0.001). This suggested that macrophages themselves are a source of the M-CSF detected in BAL fluid. To examine this possibility, slot-blot analysis of macrophage RNA was performed. Constitutive expression of comparable amounts of M-CSF mRNA and protein was found in cells from both smokers and nonsmokers. However, macrophages obtained from a randomly selected subset of four smokers but none of five nonsmokers exhibited increased production of M-CSF in response to an inflammatory stimulus, lipopolysaccharide (LPS; 5 ng/ml). M-CSF added to macrophage cultures was degraded by nonsmokers' cells as expected over 24 h.(ABSTRACT TRUNCATED AT 250 WORDS)

Lipid content of alveolar lining material collected by bronchoalveolar lavage. Improved methods for measuring the major lipid classes

Current methods for measuring lung lipids obtained by bronchoalveolar lavage are time consuming and require sample extraction with organic solvents. Here we utilized enzymatic methods for measuring the major phospholipid classes found in human bronchoalveolar lavage fluid (BALF), namely phosphatidylcholine and phosphatidylglycerol, as well as the neutral lipid cholesterol. These assays can be carried out on as little as 200 microliters lavage fluid in 96-well microtiter plates without the need for organic solvents. Results were verified by comparison with HPLC and chemical methods. The measured values by all three methods were in agreement with previous studies in which lipid analysis was performed by thin-layer chromatography. By contrast to thin-layer chromatography, however, the methods described here can be efficiently performed with small quantities of material without sacrificing accuracy. This methodology can facilitate the characterization of the major surfactant-associated lipids in BALF and foster improved understanding of the role of these lipids in human lung disease.

Glucocorticoid receptor binding in three different cell types in major depressive disorder: lack of evidence of receptor binding defect

1. In order to further understand the apparent glucocorticoid resistance in major depressive disorder, circadian variation in cortisol concentration, dexamethasone suppression and glucocorticoid receptor binding in mononuclear leukocytes, polymorphonuclear leukocytes and cultured skin fibroblasts were measured in rigidly defined major depressive disorder patients and non-depressed psychiatric controls. 2. Mononuclear leukocytes binding to glucocorticoid correlated significantly with polymorphonuclear leukocytes binding to glucocorticoid, but both determinations failed to differentiate major depressive disorder and control subjects. 3. Initial and post-dexamethasone in vitro fibroblast binding to glucocorticoid was not different between major depressive disorder and non-depressed control subjects. 4. The phenomenon of glucocorticoid resistance in major depressive disorder remains unexplained.