bluuebunny/crossref_metadata_2025 huggingface dataset:
T-cell homeostasis in humans with thymic hypoplasia due to chromosome 22q11.2 deletion syndrome
Authors: Piliero Lisa M. , Sanford Amy N. , McDonald-McGinn Donna M. , Zackai Elaine H. , Sullivan Kathleen E.
Published: October 2003

Patients with chromosome 22q11.2 deletion syndrome (DiGeorge syndrome/velocardiofacial syndrome) typically exhibit thymic hypoplasia, conotruncal cardiac defects, and hypoparathyroidism. The immunodeficiency that results from the thymic hypoplasia has been extensively described and consists primarily of T-cell lymphopenia. A curious feature of the T-cell lymphopenia is that the age-related rate of decline of T-cell numbers is slower in patients than controls. This leads to T-cell numbers in adulthood that are minimally decreased compared with controls. This suggests that homeostatic mechanisms might be acting to preserve the peripheral blood T-cell numbers in patients. We characterized changes in CD4/CD45RA and CD4/CD45RO T-cell populations in patients and controls of various ages and determined T-cell recombination excision circles and telomere length within the CD4/CD45RA population. Patients had evidence of accelerated conversion of naive to memory cells and had evidence of more extensive replicative history within the CD4/CD45RA compartment compared with controls. Oligoclonal T-cell receptor (TCR) Vβ families and missing Vβ families were seen more often in patients than controls. These data are consistent with homeostatic proliferation of T cells in patients with limited T-cell production due to thymic hypoplasia. (Blood. 2004;103:1020-1025)
Mechanisms of reduced pulmonary function after a saturation dive
Authors: Thorsen E , Segadal K , Kambestad BK
Published: October 2003

Deep saturation diving has been shown to have prolonged effects on pulmonary function. We wanted to assess the relative contribution of various factors that could contribute to these effects. Pulmonary function was, therefore, measured before and after 17 different saturation diving operations to depths of 5-450 m of sea water, corresponding to absolute pressures of 0.15-4.6 MPa. Four to fifteen divers participated in each operation. The measurements included static and dynamic lung volumes and flows, transfer factor of the lungs for carbon monoxide (TLCO), and closing volume. The dives were characterized by the cumulative hyperoxic and hyperbaric exposures, and the load of venous gas microemboli encountered during decompression was measured in 41 divers in three dives to 0.25, 1.2 and 3.7 MPa. TLCO was reduced by 8.3 +/- 7.0% mean +/- SD after the dives, this correlated with cumulative hyperoxic exposure and load of venous gas microembolism, independently of each other. Closing volume was increased and forced mid-expiratory flow rate reduced, in correlation with cumulative hyperoxic exposure. An increase in total lung capacity correlated with cumulative hyperbaric exposure. We conclude that hyperoxia, hyperbaria, and venous gas microembolism all contribute to the changes in pulmonary function after a single saturation dive, and all may explain some of the long-term effects of diving on pulmonary function.
Breathing pattern, ventilatory drive and respiratory muscle strength in patients with chronic heart failure
Authors: Ambrosino N , Opasich C , Crotti P , Cobelli F , Tavazzi L , Rampulla C
Published: October 2003

The purpose of this study was to evaluate whether chronic heart failure (CHF) may induce changes in breathing pattern and ventilatory neural drive. We studied 45 male inpatients with CHF, (25 patients in NYHA class II, 20 in class III) and 22 sex-matched post myocardial infarction patients without left ventricular dysfunction who served as controls. CHF patients underwent right heart catheterization and assessment of cardiac output by thermodilution technique. Patients and controls underwent evaluation of left ventricular ejection fraction by 2D echocardiography, spirometry, diffusion capacity, blood gases, breathing pattern, mouth occlusion pressure and respiratory muscle strength determination. Results of CHF patients were compared to controls and evaluated for differences according to the degree in severity of functional impairment. CHF patients showed a slight reduction in lung volumes and in diffusion capacity. In CHF neural drive, as assessed by mouth occlusion pressure (P0.1), was significantly increased in comparison to controls (P0.1 = 1.86 (0.7) and 1.4 (0.6) cmH2O in CHF and controls respectively). Analysis of breathing pattern showed only a slight yet significant increase in respiratory frequency while respiratory muscle strength, as assessed by measurement of maximal inspiratory and expiratory pressures (MIP and MEP respectively) was slightly reduced (MIP = 79(27) and 104(28); MEP = 111(32) and 142(33) cmH2O respectively). Observed changes were more relevant in patients with advanced NYHA functional classes whereas no relationship among indices of cardiac and respiratory function was found. We conclude that chronic heart failure induces changes in neural ventilatory drive and respiratory muscle strength related to the severity of the disease.
An exercise challenge protocol for epidemiological studies of asthma in children: comparison with histamine challenge
Authors: Haby MM , Anderson SD , Peat JK , Mellis CM , Toelle BG , Woolcock AJ
Published: October 2003

We investigated whether an exercise challenge protocol is suitable for measuring bronchial responsiveness in epidemiological studies of asthma in children, and determined its comparability with histamine challenge. The exercise challenge was 6 minutes of outdoor, free-range running at 85-90% of maximum heart rate, measured by heart rate monitor. Nose clips were worn. Distance run was measured to estimate oxygen consumption. Water content of the inspired air was < 10 mg H2O.l-1. Histamine challenge was by the rapid method. We used questionnaires to measure respiratory symptoms and skin prick tests to measure atopy. A total of 96 children aged 8-11 years were studied. Bronchial hyperresponsiveness (BHR) to exercise challenge was defined as a fall in forced expiratory volume in one second (FEV1) of 13% of greater. Eleven children had a positive response to exercise challenge and 11 to histamine challenge but 12 responded to one challenge and not to the other. The correlation coefficient between the two tests was 0.65 (p = 0.0001). Exercise challenge thus proved to be a practical epidemiological tool for objective measurements of bronchial responsiveness in children. In this sample, some children responded to one challenge and not to the other which suggests that the two challenges identify different abnormalities of the airways.
Remission of childhood asthma after long-term treatment with an inhaled corticosteroid (budesonide): can it be achieved? Dutch CNSLD Study Group
Authors: van Essen-Zandvliet EE , Hughes MD , Waalkens HJ , Duiverman EJ , Kerrebijn KF
Published: October 2003

This study was undertaken in order to determine whether long-term treatment with inhaled corticosteroid can induce a remission in childhood asthma, and to decide when stabilization of airway responsiveness occurred. We therefore carried out, an extended follow-up of 28-36 months in one of two groups of children who participated in a long-term intervention study. This former study had shown that long-term (median follow-up 22 months) treatment with inhaled corticosteroid plus beta 2-agonist improves symptoms, airway calibre and airway responsiveness in children with asthma, compared with beta 2-agonist alone. On treatment with inhaled corticosteroid plus beta 2-agonist, airway calibre did not further improve after 4 months, whereas the provocative dose of histamine which causes a 20% fall in forced expiratory volume in one second (PD20) histamine showed gradual improvement without reaching an apparent plateau. Remission was defined as being symptom free during any 8 month period. Of the 58 children originally randomized to receive 0.2 mg salbutamol, plus 0.2 mg budesonide, t.i.d., five children withdrew: three due to lack of motivation, one for psychological reasons, and one due to a deterioration of asthma. One patient was hospitalized because of an asthma exacerbation. Airway calibre showed no improvement after 4 months up to 36 months. Mean PD20 histamine stabilized after 20 months at 2.1 doubling doses above baseline, but at a subnormal level of 80 micrograms. Symptoms improved during the first 18 months, and may have been improving further, but slowly, during the period between 18 and 36 months.(ABSTRACT TRUNCATED AT 250 WORDS)
Lung deposition of budesonide inhaled via Turbuhaler: a comparison with terbutaline sulphate in normal subjects
Authors: Borgstrom L , Bondesson E , Moren F , Trofast E , Newman SP
Published: October 2003

We wanted to evaluate whether lung deposition of budesonide and terbutaline sulphate differs, and to determine lung deposition of budesonide inhaled at different peak inspiratory flows, through Turbuhaler. Lung deposition of budesonide, a lipophilic substance, and of terbutaline sulphate, a hydrophilic substance, was therefore compared, after administration via an inspiratory flow-driven, multi-dose, powder inhaler (Turbuhaler, Astra Draco AB) to 10 healthy volunteers. The radionuclide 99mTc was used to label drug particles, and radioactivity, indicating drug deposition, was measured using a gamma camera. Budesonide was inhaled at a normal flow of 58 l.min-1 and at a slow flow of 36 l-min-1. At the faster flow, a mean +/- SD 27.7 +/- 9.5% of the metered dose was deposited in the lung and at the slower flow 14.8 +/- 3.3% was deposited (p < 0.001). Mean lung deposition of terbutaline sulphate inhaled at 57 l.min-1 was 27.0 +/- 7.7%. We conclude that inspiratory flow has an important effect on lung deposition, but water solubility appears to have no effect.
Gamma-interferon modifies guinea pig airway functions in vitro
Authors: Chen H , Munakata M , Amishima M , Ukita H , Masaki Y , Homma Y , Kawakami Y
Published: October 2003

Cytokines produced by T-lymphocytes may have significant roles in the airway inflammation seen in bronchial asthma. Gamma interferon (IFN-gamma), a T-cell derived cytokine, is known to modify functions of both immune and non-immune cells. In this study, we investigated whether IFN-gamma can modify guinea pig airway functions in vitro. The isometric tension of guinea pig airway strips was measured in a tissue bath filled with Krebs-Henseleit solution. Contracting responses to carbachol and KCl, and the relaxing response to isoproterenol (ISO) were examined. Effects of IFN-gamma were examined by comparing responses of the strips incubated with or without IFN-gamma (1000 U.ml-1; 25,000 U.ml-1). Contracting responses to carbachol and KCl were not affected by the incubation with IFN-gamma other than slight increased in maximum contraction by carbachol after 5 hours incubation with 25,000 U.ml-1 of IFN-gamma. Both 1 and 5 h incubation of strips with 25,000 U.ml-1 IFN-gamma significantly increased the sensitivity to ISO (p < 0.01 and p < 0.05, respectively) without affecting maximum relaxation. The effect of IFN-gamma on ISO relaxation was abolished by the denudation of airway epithelium from strips, indomethacin (2 microM), and cycloheximide (70 microM) but not by N omega-nitro-L-arginine methyl ester (30 microM). In addition, heat-inactivated IFN-gamma and bacterial endotoxin (LPS, 0.625 pg.ml-1) had no effect on ISO relaxation. These results suggest that IFN-gamma is able to modify airway smooth muscle response to beta-adrenergic agonist by inducing release of prostanoids from airway epithelium.
Mucolytic treatment with N-acetylcysteine L-lysinate metered dose inhaler in dogs: airway epithelial function changes
Authors: Tomkiewicz RP , App EM , Coffiner M , Fossion J , Maes P , King M
Published: October 2003

N-acetylcysteine L-lysinate Nacystelyn (L-NAC) is a newly synthesized mucolytic agent, of which the action in vivo has not been well defined. In six healthy mongrel dogs, the rheological properties of mucus, its mucociliary and cough clearability, and the transepithelial potential difference (PD) of the tracheobronchial epithelium were evaluated after placebo and L-NAC metered dose inhaler (MDI) aerosols. The principal index of mucus rigidity, log G*, decreased at all airway sites with L-NAC administration, i.e. the mucus became less rigid and more deformable (the overall change in G* was 0.29 log units, i.e. ca. twofold decrease). The viscoelasticity-derived mucus transportability parameters, mucociliary (MCI) and cough (CCI) clearability indices, increased with L-NAC MDI, particularly CCI, which predicts the effect of mucus rheology on cough clearability. PD increased significantly with L-NAC administration at all measurement sites, which appears to be a novel effect for a direct acting mucolytic agent. Tracheal mucus linear velocity (TMV) increased after L-NAC compared with placebo, as did the normalized frog palate transport rate (NFPTR). The increase in NFPTR was greater than that predicted from the mucus rheological properties alone, suggesting that L-NAC still resident in the collected mucus stimulated the frog palate cilia. The index of mucus flux, the collection rate in mg.min-1, was higher with L-NAC compared with placebo. From our results, we conclude that L-NAC shows potential benefit in terms of improving mucus rheological properties and clearability. It may act, in part, by stimulating the fresh secretion of mucus of lower viscoelasticity. The stimulation of mucociliary clearance could be related to ion flux changes, as indicated by the increase in PD.
The intrabronchial microbial flora in chronic bronchitis patients: a target for N-acetylcysteine therapy?
Authors: Riise GC , Larsson S , Larsson P , Jeansson S , Andersson BA
Published: October 2003

Chronic bronchitis is common among smokers, often together with recurrent infectious exacerbations. Streptococcus pneumoniae and Haemophilus influenzae are the pathogens traditionally considered most important. N-acetylcysteine (NAC) treatment has been shown to reduce the number of infectious exacerbations in patients with chronic bronchitis. The mechanism behind this is unknown. We attempted to characterize the intrabronchial bacterial flora in patients with chronic bronchitis in an infection-free interval, and to determine whether pharmacological and immunological factors effected the bacterial occurrence. Twenty two smokers with non-obstructive chronic bronchitis, 19 smokers with chronic bronchitis and chronic obstructive pulmonary disease (COPD) and 14 healthy nonsmokers underwent bronchoscopy. To obtain uncontaminated intrabronchial samples, a protected specimen brush was used. Quantitative bacterial cultures and virus isolations were performed. Significantly positive bacterial cultures (> 1,000 colony-forming units (cfu).ml-1) were found only in the patients. S. pneumoniae and H. influenzae were found in five patients, and only in the patients without NAC treatment. The most common bacterium was alpha-haemolytic streptococcus. Negative cultures were more common in the healthy controls. Of the various factors examined, only NAC medication had an influence on bacterial numbers. Significantly fewer patients with NAC medication had positive cultures (3 out of 16) than in the group of patients without NAC therapy (15 out of 21). Our results confirm that chronic bronchitis in smokers leads to increased intrabronchial bacterial colonization. We could also confirm that 1,000 cfu.ml-1 is an adequate cut-off level for significant bacterial growth when using the protected specimen brush. NAC medication was associated with low bacterial numbers.
Two family outbreaks of Chlamydia pneumoniae infection
Authors: Blasi F , Cosentini R , Denti F , Allegra L
Published: October 2003

During autumn 1992, we observed two unrelated family outbreaks of Chlamydia pneumoniae infection. Family A consisted of grandmother (aged 77 yrs), father (aged 41 yrs), mother (aged 38 yrs), daughter (aged 10 yrs), and two sons (aged 6 yrs and 3 months, respectively). The grandmother and daughter suffered from pneumonia, father from pharyngitis and bronchitis and the older son from mild bronchitis. No symptoms were recorded in the mother and younger son. Symptomatic subjects showed a fourfold increase in immunoglobulin G (IgG) titre for Chlamydia pneumoniae, determined by a microimmunofluorescence test with specific antigen (TW-183). Other serological studies against Mycoplasma pneumonia, Legionella pneumophila, influenza virus type A and B, adenovirus and respiratory syncytial virus (RSV) were negative. Sputum culture gave a positive result for Haemophilus influenzae, colony forming units (cfu) = 10(4).ml-1 in the grandmother. No serum positivity was recorded in the mother and younger son, who remained asymptomatic. All symptomatic patients were successfully treated with macrolides. Family B consisted of mother (aged 63 yrs) and daughter (aged 36 yrs). Both suffered from Chlamydia pneumoniae pneumonia. Diagnosis was made by means of serological microimmunofluorescence test, and direct identification using an indirect immunofluorescence test on pharyngeal swab. Sputum culture and other serological tests remained negative. Both patients were successfully treated with macrolides. These observations emphasize the relevance of Chlamydia pneumoniae in family cluster respiratory infections.
Characterization of protein-antiproteinase imbalance in bronchoalveolar lavage from patients with pneumonia
Authors: Braun J , Dalhoff K , Schaaf B , Wood WG , Wiessmann KJ
Published: October 2003

In order to clarify the mode of inactivation of alpha1-proteinase inhibitor (alpha 1-PI) in pneumonia, 21 immunocompetent patients and 19 immunocompromised patients with acute pneumonia (Groups I and II) were studied. Nine patients successfully treated for pneumonia and 10 healthy volunteers served as controls (Groups III and IV, respectively). The concentrations of alpha 1-PI, elastase and myeloperoxidase (MPO) in bronchoalveolar lavage fluid (BALF) were determined using a luminometric assay. Elastase inhibition capacity was determined using a colorimetric assay. Thus, the functional activity of alpha 1-PI was calculated. Both elastase and MPO were significantly higher in group I, when compared with the other groups. The mean concentration of alpha 1-PI was significantly higher in patients with acute pneumonia (Group I 13 mg.l-1, Group II 4.22 mg.l-1) than in Groups III and IV (2.65 and 0.33 mg.l-1, respectively), whereas, the proportion of active alpha 1-PI was significantly lower in Group I than in the other groups. Only a small proportion was present as a complex with elastase (ca. 5.9%) or in oxidised form (ca. 4.8%), 85% of alpha 1-PI was irreversibly proteolyzed. This resulted in free elastase activity in 7 of the 40 patients (18%) with acute pneumonia. We conclude that functional activity of alpha 1-PI is markedly impaired due to irreversible proteolysis in acute pneumonia, despite high immunological concentrations.
Definition and diagnosis of occupational asthma
Authors: Cartier A
Published: October 2003

Asthma is the most frequent occupational lung disease. The diagnosis of occupational asthma, defined as variable airways narrowing, causally related to exposure in the working environment to specific airborne dusts, gases, vapours or fumes, needs to be confirmed by objective means. This article reviews the different steps of investigation which are: history, pulmonary function tests, immunological tests, monitoring of peak expiratory flows and nonallergic bronchial responsiveness and, finally, the gold standard, specific bronchial provocation.
Aluminium potroom asthma: the Norwegian experience
Authors: Kongerud J , Boe J , Soyseth V , Naalsund A , Magnus P
Published: October 2003

Work-related asthma in aluminium potroom workers, is reviewed and discussed, mainly on the basis of own investigations. The occurrence of work-related asthma has been shown to be associated with the duration of potroom employment, although the prevalence of asthmatic symptoms is not significantly different from that of the general population. Typical manifestations of occupational asthma are described in potroom workers, and a close relationship between the levels of fluoride exposure and work-related asthmatic symptoms has been observed. The existence of occupational asthma in aluminium potroom workers has been confirmed by characteristic patterns of repeated peak flow measurements, supported by changes in methacholine responsiveness in workers with suspected work-related asthma. However, no immunological test is available to establish the diagnosis. Methacholine challenge appears to be inappropriate for screening aluminium potroom workers in order to detect work-related asthma. Current smoking, but not self-reported allergy, is a risk factor for potroom asthma. A family history of asthma and previous occupational exposure may have some effect on the risk of developing symptoms. The prognosis of potroom asthma seems to depend on early replacement to unexposed work. The pathogenetic mechanisms are unknown, although some studies indirectly imply a hypersensitivity reaction. Future studies involving specific bronchial challenge appear to be necessary to find the causal agent(s) of aluminium potroom asthma.
Lipoma of the external thoracic wall
Authors: Sulzer MA , Goei R , Bollen EC , Theunissen PH , Maesen FP
Published: October 2003

We report the case history of an external thoracic wall lipoma, which was noticed incidentally on a chest roentgenogram because of its calcification. A probable diagnosis was made by computer tomography. Because of the increase in size of the tumour it was removed surgically, but no evidence of malignant degeneration was found.
Significance of lipopolysaccharide-binding protein (an acute phase protein) in monitoring critically ill patients
Authors: Prucha Miroslav , Herold Ivan , Zazula Roman , Dubska Ladislava , Dostal Miroslav , Hildebrand Thomas , Hyanek Josef
Published: October 2003

Introduction

The present study was conducted to assess the value of serum concentration of lipopolysaccharide-binding protein (LBP) in patients with systemic inflammatory response syndrome (SIRS), sepsis and septic shock with respect to its ability to differentiate between infectious and noninfectious etiologies in SIRS and to predict prognosis.

Methods

This prospective cohort study was conducted in a multidisciplinary intensive care unit. Sixty-eight patients, admitted consecutively to the intensive care unit and who met criteria for SIRS, sepsis or septic shock were included. Serum LBP was measured using an immunochemiluminiscence assay.

Results

Serum levels of LBP were significantly increased in patients with SIRS (n = 40; median 30.6 μg/ml, range 9.2–79.5 μg/ml), sepsis (n = 19; median 37.1 μg/ml, range 11.8–76.2 μg/ml) and septic shock (n = 9; median 59.7 μg/ml, range 31.1–105 μg/ml), as compared with levels in the healthy volunteers (5.1 ± 2.2 μg/ml; P < 0.0001). Serum LBP at study entry was statistically significantly lower in patients with SIRS than in those with septic shock (P < 0.014); no statistically significant difference existed between patients with SIRS and those with sepsis (P = 0.61). Specificity and sensitivity of an LBP concentration of 29.8 μg/ml to distinguish between infectious and noninfectious etiologies for SIRS were 50% and 74.2%, respectively. There was no statistically significant difference in LBP concentration between survivors and nonsurvivors in both groups of patients. Furthermore, in septic patients the LBP response appeared to exhibit a decreased magnitude.

Conclusion

LBP is a nonspecific marker of the acute phase response and cannot be used as a diagnostic tool for differentiating between infectious and noninfectious etiologies of SIRS.
Apoptosis-induced proteinase 3 membrane expression is independent from degranulation
Authors: Durant Stéphanie , Pederzoli Magali , Lepelletier Yves , Canteloup Sandrine , Nusbaum Patrick , Lesavre Philippe , Witko-Sarsat Véronique
Published: October 2003

Proteinase 3 (PR3) and human neutrophil elastase (HNE) are serine proteinases stored in the azurophilic granules of neutrophils. In contrast to HNE, PR3 is the target of antineutrophil cytoplasm antibodies (ANCA) in Wegener’s granulomatosis. The mechanisms leading to the membrane expression of PR3 and HNE are still unclear and appear to be critical to understand the pathophysiological role of ANCA. Stably transfected rat basophilic cell lines (RBL) with PR3 or HNE were used to analyze the PR3 and HNE secretion mechanisms and differentiate between them. RBL cells were lacking endogenous PR3 and HNE. They were stably transfected with HNE or PR3 or an inactive mutant of PR3 (PR3S203A). Using the calcium ionophore A23187 as a secretagogue, higher serine proteinase activity was secreted in the supernatant of RBL/HNE than in RBL/PR3. It is interesting that PR3 and PR3/S203A were also expressed at the plasma membrane, thus demonstrating that serine protease activity was not required for plasma membrane expression. In contrast, no expression of plasma membrane HNE could be detected in RBL/HNE. Apoptosis induced by etoposide was evaluated by DNA fragmentation, the presence of cytoplasmic histone-associated DNA fragments, and annexin V labeling. No membrane HNE was detected in RBL/HNE. In contrast, in RBL/PR3 and in RBL/PR3S203A, the membrane expression of PR3 and PR3S203A increased with etoposide concentrations and appeared closely related to annexin V labeling. Our data suggest that membrane PR3 originates from two distinct pools, the granular pool mobilized following degranulation or a plasma membrane pool mobilized upon apoptosis.
Notch signaling in the immune system
Authors: Hoyne Gerard F
Published: October 2003

Notch signaling plays a preeminent role during development in not only regulating cell fate decisions, but it can also influence growth and survival of progenitor cells. In the immune system, Notch is required for the maintenance of hematopoietic stem cells and in directing T- versus B-lineage commitment. In this review, I will summarize some of the recent findings relating to the function of Notch in the immune system during lymphocyte development and in the generation and function of mature cells.
Monoclonal LYM-1 antibody-dependent cytolysis by human neutrophils exposed to GM-CSF: auto-regulation of target cell attack by cathepsin G
Authors: Ottonello Luciano , Epstein Alan L , Mancini Marina , Dapino Patrizia , Dallegri Franco
Published: October 2003

Murine monoclonal antibody (mAb) Lym-1 is an immunoglobulin G2a specific for certain human leukocyte antigen-DR variants expressed on the surface of malignant B cells. It has been proposed for serotherapy in patients with B lymphomas. We have previously shown thatmAb Lym-1 synergizes with granulocyte macrophage-colony stimulating factor to promote Raji B-lymphoid cell lysis by human neutrophils via the intervention of neutrophil Fc receptors type II and D-mannose-inhibitable interactions between CD11b–CD18 integrins and CD66b glycoproteins. Here, we provide evidence that the process is oxygen-independent by inference related to the release of primary granules and is regulated by cathepsin G activity. The lysis was indeed reproduced by replacing normal neutrophils with cells from three patients suffering from chronic granulomatous disease, i.e., neutrophils genetically incapable of generating oxidants. Moreover, the lysis was inhibited by the serine protease inhibitor 3,4-dichloroisocoumarin and by Z-glycyl-leucyl-phenyl-chloromethyl ketone (Z-Gly-Leu-Phe-CMK), which blocks cathepsin G. Conversely, the lysis was unaffected by N-methoxysuccinyl-alanyl-alanyl-prolyl-alanyl-CMK (MeOSuc-Ala-Ala-Pro-Ala-CMK; elastase inhibitor) and MeOSuc-Ala-Ala-Pro-valine (Val)-CMK, which inhibits elastase and proteinase 3. The ability of neutrophils, engaged in cytolysis, to release cathepsin G was proved by detecting this enzymatic activity spectrophotometrically and immunocytochemically. Moreover, inhibition of cathepsin G activity by concentrations of Z-Gly-Leu-Phe-CMK, incapable of affecting elastase activity, was found to reduce the release of elastase and myeloperoxidase from neutrophils under conditions similar to those used for cytolytic assays. These findings suggest that neutrophils auto-regulate their lytic efficiency by controlling the exocytosis of primary granules via their cathepsin G activity.
Functional repertoire of dendritic cells generated in granulocyte macrophage-colony stimulating factor and interferon-α
Authors: Della Bella Silvia , Nicola Stefania , Riva Antonio , Biasin Mara , Clerici Mario , Villa Maria Luisa
Published: October 2003

Monocyte-derived dendritic cells (DCs) generated in granulocyte macrophage-colony stimulating factor GM-CSF) and interleukin-4 (IL-4–DCs) are used to enhance antitumor immunity in cancer patients, although recent evidence suggests that their functional repertoire may be incomplete; in particular, IL-4–DCs appear unable to induce type 2 cytokine-producing T helper (Th) cells. To assess whether type 1 interferon (IFN) could replace IL-4 and generate DCs with a more complete repertoire, we characterized in detail DCs generated from human monocytes cultured with GM-CSF and IFN-α (IFN–DCs). We found that IFN-α induces DC differentiation more efficiently than IL-4, yielding similar numbers of DCs in a shorter time and that this differentiation persists upon removal of cytokines. Although IFN–DCs had a more mature immunophenotype than IL-4–DCs, showing higher expression of CD80, CD86, and CD83, they still preserved comparable endocytic and phagocytic capacities and responsiveness to maturation stimuli. IFN–DCs had strong antigen-presenting capacity, inducing intense proliferation of T cells to alloantigens or influenza virus. Moreover, IFN–DCs produced lower levels of IL-12p70 and higher levels of IFN-α, IL-4, and IL-10 than IL-4–DCs. As a consequence of this different pattern of cytokine secretion, IFN–DCs induced T cells to produce type 1 (IFN-γ) and type 2 (IL-4 and IL-10) cytokines, and as expected, IL-4–DCs induced only Th1 differentiation. As immune responses with extreme Th1 bias are considered inadequate for the induction of optimal, systemic antitumor immunity, the ability of IFN–DCs to promote more balanced cytokine responses may suggest the advisability to consider these cells in the development of future, DC-based immunotherapy trials.
The Src kinase Lyn is a negative regulator of mast cell proliferation
Authors: Hernandez-Hansen Valerie , Mackay Graham A , Lowell Clifford A , Wilson Bridget S , Oliver Janet M
Published: October 2003

Previous investigators have reported that deletion of the protein tyrosine kinase Lyn alters mast cell (MC) signaling responses but does not affect or reduces the cytokine-mediated proliferation of mouse bonemarrow-derived MC (BMMC) precursors and of mature MC. We observed that Lyn-deficient mice have more peritoneal MC than wild-type (WT) mice. Studies to explore this unexpected result showed that Lyn−/− BM cells expand faster than WT cells in response to interleukin (IL)-3 and stem-cell factor over the 4–5 weeks required to produce a >95% pure population of granular, receptor with high affinity for immunoglobulin E-positive BMMC. Furthermore, differentiated Lyn−/− BMMC continue to proliferate more rapidly than WT BMMC and undergo less apoptosis in response to cytokine withdrawal. Additionally, Lyn−/− BMMC support greater IL-3-mediated phosphorylation of the prosurvival kinase, Akt, and the proliferative kinase, extracellular-regulated kinase 1/2. These results identify Lyn as a negative regulator of murine MC survival and proliferation.
Prevention of Descending Pneumonia in Rats with Perflubron‐delivered Tobramycin
Authors: Dickson Eric W. , Doern Gary V. , Trevino Leo , Mazzoni Michelle , Heard Stephen O.
Published: October 2003

Objectives: Patients undergoing emergent endotracheal intubation are at increased risk for developing pneumonia. Although numerous strategies have been investigated to reduce ventilator‐associated pneumonia (VAP), the incidence of VAP and its associated mortality remains high. This investigation tested the hypothesis that LiquiVent (Alliance Pharmaceutical, San Diego, CA–LV) delivered antibiotics (via spray‐dried microspheres–SDM) would improve survival in a rat model of descending gram‐negative pneumonia. Methods: Wistar rats (n= 49) were randomized to receive prophylaxis with 1) nothing (controls); 2) intramuscular (IM) tobramycin, 3) intratracheal LV plus SDM shells (vehicle), 4) intratracheal LV plus SDM shells plus IM tobramycin, or 5) intratracheal LV plus SDM containing 1 mg/kg of tobramycin. All interventions were given 24 hours before a bacterial challenge with 108 colony‐forming units of intratracheal Klebsiella pneumoniae. Mortality at ten days was the sole outcome measure. Survival in individual groups was compared with controls by Fisher's exact test with Bonferroni correction for multiple comparisons. Results: All animals in the control group died of pneumonia within ten days of bacterial inoculation (0% survival). Prophylaxis with either IM tobramycin or SDM vehicle plus IM tobramycin provided no protection (0% survival). This is in sharp contrast to the cohort receiving pretreatment with tobramycin‐containing SDM delivered via LV, in which 60% of the animals survived to study completion (p < 0.05). Conclusions: Prophylaxis with SDM containing antibiotics delivered in low‐dose LV provided significant protection in a rat model of descending gram‐negative pneumonia. These data support the hypothesis that perfluorocarbon‐delivered intratracheal antimicrobials may be useful in the prevention of VAP.
Focused Training of Emergency Medicine Residents in Goal‐directed Echocardiography: A Prospective Study
Authors: Jones Alan E. , Tayal Vivek S. , Kline Jeffrey A.
Published: October 2003

Objectives: To determine if a focused transthoracic echocardiography (TTE) training course would improve the accuracy of completion and interpretation of a goal‐directed TTE by emergency medicine residents. Methods: This was a prospective, observational, educational study of the impact of a focused training course on the change in physician performance on pre‐ and postcourse examinations testing competency in goal‐directed TTE defined by five criteria: 1) image orientation, 2) anatomy identification, 3) chamber size grading, 4) ventricular function estimation, and 5) pericardial effusion identification. Subjects included were emergency medicine residents with between ten and 20 hours of noncardiac ultrasound didactics and between 20 and >150 proctored noncardiac ultrasound examinations. All underwent five hours of focused echocardiography didactics and one hour of proctored practical echocardiography training designed and implemented by an emergency physician ultrasound director and a cardiologist. Before the start of the training course, participants completed two examinations: 1) written 23‐question test on the above concepts and 2) performance of a TTE on a healthy subject testing 16 elements that define a properly performed examination. After the training course, participants again completed both examinations. Results: A total of 21 emergency medicine residents qualified for and underwent standardized testing and training. The percentage correct on the precourse written examination was 54% (95% CI = 50% to 59%), and the postcourse examination score was 76% (95% CI = 71% to 80%) (p < 0.005, paired t‐test). The percentage correct on the precourse practical examination was 56% (95% CI = 51% to 60%), and the postcourse examination score was 94% (95% CI = 91% to 96%) (p < 0.005). Conclusions: A focused six‐hour echocardiography training course significantly improved emergency medicine residents' percentage scores on both written and practical examinations testing essential components required for correct goal‐directed TTE performance and interpretation.
The Emergency Severity Index Triage Algorithm Version 2 Is Reliable and Valid
Authors: Eitel David R. , Travers Debbie A. , Rosenau Alexander M. , Gilboy Nicki , Wuerz Richard C.
Published: October 2003

Objectives:Initial studies have shown improved reliability and validity of a new triage tool, the Emergency Severity Index (ESI), over conventional three‐level scales at two university medical centers. After pilot implementation and validation, the ESI was revised to include pediatric and updated vital signs criteria. The goal of this study was to assess ESI version (v.) 2 reliability and validity at seven emergency departments (EDs) in three states.Methods:In part 1, interrater reliability was assessed using weighted kappa analysis of written training cases and postimplementation by a random sampling of actual patient triages. In part 2, validity was analyzed using a prospective cohort with stratified random sampling at each site. The ESI was compared with outcomes including resource consumption, inpatient admission, ED length of stay, and 60‐day all‐cause mortality.Results:Weighted kappa analysis of interrater reliability ranged from 0.70 to 0.80 for the written scenarios (n= 3,289) and 0.69 to 0.87 for patient triages (n= 386). Outcomes for the validity cohort (n= 1,042) included hospitalization rates by ESI triage level: level 1, 83%; 2, 67%; 3, 42%; 4, 8%; level 5, 4%. Sixty‐day all‐cause mortality by triage level was as follows: level 1, 25%; 2, 4%; 3, 2%; 4, 1%; and 5, 0%.Conclusions:ESI v. 2 triage produced reliable, valid stratification of patients across seven sites. ESI triage should be evaluated as an ED casemix identification system for uniform data collection in the United States and compared with other major ED triage methods.
National EMS Research Agenda: Proceedings of the Implementation Symposium
Authors: Sayre Michael R. , White Lynn J. , Brown Lawrence H. , McHenry Susan D.
Published: October 2003

The National EMS Research Agenda identified eight recommendations for improving the conduct of emergency medical services (EMS) research in the United States. EMS leaders from across the country attended a two‐day symposium to discuss implementation of the Research Agenda recommendations. The participants suggested specific methods to move the recommendations forward. These included improving training opportunities for EMS researchers, stimulating increases in available funding sources, facilitating the integration of research into practice, and crafting alterations within the regulatory environment. Participants felt that EMS must be more broadly integrated into the public health continuum. Federal agencies, states, local governments, charitable foundations, and corporations are asked to examine their practices to increase opportunities for participation in EMS research programs at all stages of the process.
Evaluation of a New High‐viscosity Octylcyanoacrylate Tissue Adhesive for Laceration Repair: A Randomized, Clinical Trial
Authors: Singer Adam J. , Giordano Philip , Fitch Jeffrey L. , Gulla Janet , Ryker Dennis , Chale Stuart
Published: October 2003

Objective: Tissue adhesives have recently been approved for skin closure. Their low viscosity may result in inadvertent migration. The authors compared the tendency of the adhesive to migrate after laceration closure with a high‐ or low‐viscosity octylcyanoacrylate (OCA). Methods: This was a randomized, clinical trial set in university and community‐based emergency departments. Participants included patients with simple traumatic lacerations. Patients were randomized to laceration closure with low‐ or high‐viscosity OCA tissue adhesive. The outcome measured was immediate adhesive migration (interobserver agreement, κ= 0.90). Data analysis was performed with proportions compared with chi‐square and Fisher's exact tests. Results: Eighty‐four patients were randomized to low‐ (n= 42) or high‐ (n= 42) viscosity OCA tissue adhesive. Groups were similar in baseline patient and wound characteristics. The high‐viscosity OCA was less likely to migrate than the lower‐viscosity agent (21% vs. 78%, p < 0.001; odds ratio = 0.3, 95% confidence interval = 0.1 to 0.5). The proportion of patients who noted a sensation of heat during OCA application was higher in the high‐viscosity groups (44% vs. 26% respectively, p = 0.11); however, all such patients in both groups would use the device again. At 14 days, there were no wound infections in either group. There was one dehiscence in the high‐viscosity group. Conclusions: The high‐viscosity OCA tissue adhesive was less likely to migrate than the lower‐viscosity device. Wound dehiscence and infection rates were acceptably low in both treatment groups.
Emergency Medicine Subinternship: Can We Provide a Standard Clinical Experience?
Authors: Coates Wendy C. , Gendy Mary S. , Gill Andrew M.
Published: October 2003

Medical students have varied experiences on the emergency medicine (EM) subinternship. Didactic curricula can be standardized. Objectives: To determine if uniformity in clinical curricula is possible by assessing whether students can see patients with certain chief complaints (CC). Methods: Prospective interventional analysis at a public teaching hospital. Control group (CG) students saw patients of their choice and recorded encounters in logbooks. Test group (TG) students were asked to see at least one patient with: orthopedic injury (OR); asthma exacerbation (AE); acute coronary syndrome (ACS); traumatic injury (TR); laceration (LAC); or diabetic ketoacidosis (DKA). TG students prospectively recorded these patients on a separate logbook page. Logbooks were reviewed by two investigators to determine if a patient with each diagnosis was seen. Chi‐square analysis tested for differences in sample proportions between TG and CG. Multivariate analyses controlled for TG, specialty choice, and gender. p < 0.05 represented statistical significance. Results: One hundred fifty (88 TG; 62 CG) students participated. Differences existed between TG and CG in the proportion of students who saw a patient with each CC: OR: 93% TG, 69% CG (p < 0.0001); AE: 86% TG, 63% CG (p < 0.0008); ACS: 97% TG, 58% CG (p < 0.0001); TR: 97% TG, 58% CG (p < 0.0001); LAC: 98% TG, 89% CG (p < 0.0220); DKA: 68% TG, 47% CG (p < 0.0086). Logistic regressions explaining the probability of seeing each CC showed the variable controlling for TG was positive and significant for 5 CCs: p = 0.0013 (OR); 0.0038 (AE); 0.0001 (ACS); 0.0001 (TR); 0.0229 (DKA). No difference was found for LAC: p = 0.0570. Conclusions: Students can be directed to see patients with particular CCs. TG students saw more patients with certain CCs than CG students, p < 0.0001. This intervention can help educators provide a well‐rounded, uniform clinical EM experience.
Intravenous 2-Deoxy-d-Glucose Injection Rapidly Elevates Levels of the Phosphorylated Forms of p44/42 Mitogen-Activated Protein Kinases (Extracellularly Regulated Kinases 1/2) in Rat Hypothalamic Parvicellular Paraventricular Neurons
Authors: Khan Arshad M. , Watts Alan G.
Published: October 2003

CRH neurons within the medial parvicellular part of the hypothalamic paraventricular nucleus (PVHmp) can respond to afferent inputs encoding stress-related information by initiating peptide synthesis (signaling cascades, transcription, and translation) and/or peptide release. However, understanding these cellular events is hampered by three outstanding issues: 1) neural inputs that activate CRH neurons remain incompletely identified; 2) the identity and temporal dynamics of signaling pathways within CRH neurons are poorly understood; and 3) the precise coupling of the first two issues has not been established. Here, we report that the phosphorylated forms of p44/p42 MAPKs (pERK1/2) are rapidly detected in PVHmp cells after iv infusion of the antimetabolite, 2-deoxy-d-glucose (2-DG). Combined immunocytochemistry and in situ hybridization revealed that pERK1/2 immunoreactivity is detectable 10 min after 2-DG infusion not only within most PVHmp neurons containing CRH mRNA (78.6% of mean total CRH cells counted) but also in many non-CRH neurons (45.5% of mean total sampled cells). In contrast, Fos protein in the PVHmp was not detected within this time period, consistent with the known time course for its translation. Stress associated with halothane exposure also robustly elevated pERK1/2 levels in PVHmp neurons approximately 10 min after exposure. Our results implicate pERK1/2 in stress-induced activation of CRH neurosecretory cells and underscore their utility as indices of rapid cellular activation. Because 2-DG-induced activation of CRH gene transcription in these neurons requires a catecholaminergic input, our data also suggest that pERK1/2 could couple afferent catecholaminergic signals with CRH gene expression in these neurons.
Functional network integration of embryonic stem cell-derived astrocytes in hippocampal slice cultures
Authors: Scheffler Björn , Schmandt Tanja , Schröder Wolfgang , Steinfarz Barbara , Husseini Leila , Wellmer Jörg , Seifert Gerald , Karram Khalad , Beck Heinz , Blümcke Ingmar , Wiestler Otmar D. , Steinhäuser Christian , Brüstle Oliver
Published: October 2003

Embryonic stem (ES) cells provide attractive prospects for neural transplantation. So far, grafting strategies in the CNS have focused mainly on neuronal replacement. Employing a slice culture model, we found that ES cell-derived glial precursors (ESGPs) possess a remarkable capacity to integrate into the host glial network. Following deposition on the surface of hippocampal slices, ESGPs actively migrate into the recipient tissue and establish extensive cell-cell contacts with recipient glia. Gap junction-mediated coupling between donor and host astrocytes permits widespread delivery of dye from single donor cells. During maturation,engrafted donor cells display morphological, immunochemical and electrophysiological properties that are characteristic of differentiating native glia. Our findings provide the first evidence of functional integration of grafted astrocytes, and depict glial network integration as a potential route for widespread transcellular delivery of small molecules to the CNS.
Trophoblasts acquire a chemokine receptor, CCR1, as they differentiate towards invasive phenotype
Authors: Sato Yukiyasu , Higuchi Toshihiro , Yoshioka Shinya , Tatsumi Keiji , Fujiwara Hiroshi , Fujii Shingo
Published: October 2003

At the human feto-maternal interface, trophoblasts differentiate towards extravillous trophoblasts (EVTs) and form the cell column. EVTs acquire invasive activity in the distal part of the cell column and begin to migrate into the maternal tissue. We previously reported that dipeptidyl peptidase IV(DPPIV) is expressed on EVTs in the proximal part of cell column and is involved in the inhibition of their migration. Because DPPIV has been shown to degrade several chemokines, we examined possible roles of chemokines in EVT migration.

Immunohistochemistry demonstrated that C-C chemokine receptor 1 (CCR1) was hardly detected on cytotrophoblasts and syncytiotrophoblast but was expressed on EVTs in the cell column. In vitro, CCR1 protein was also present on the surface of EVTs that grew out from chorionic villous explants cultured under 20% O2. Chemokines that can bind to CCR1 (CCR1 ligands), such as regulated on activation, normal T cell expressed and secreted (RANTES) and macrophage inflammatory protein-1α (MIP-1α), were confirmed in the decidual tissues by RT-PCR and immunohistochemistry. These CCR1 ligands promoted the migration of the EVTs that were isolated from the explant cultures in vitro. These results indicate that CCR1 is expressed on trophoblasts as they differentiate to EVTs and that CCR1 ligands produced from the decidual tissue induce EVT migration.

By contrast, CCR1 was scarcely expressed on EVTs that grew out from villous explants cultured in 1% O2, indicating that a relatively high oxygenic environment is needed to induce CCR1 expression. Moreover, CCR1 expression on the isolated EVTs was significantly reduced in the presence of decidua-conditioned medium. Such regulation of CCR1 by surrounding oxygenic and decidual environments supports a close correlation between EVT invasion and their expression of CCR1.

This study demonstrates that trophoblasts acquire CCR1 as they differentiate to an invasive phenotype at the villus-anchoring sites and indicates a novel role for the chemokine-CCR1 system in the initial step of trophoblastic invasion towards the maternal tissue.