Health-related QOL of elderly patients with pulmonary M. avium complex disease in a university hospital

BACKGROUND

Little is known about the clinical characteristics and health-related quality of life (HQOL) of elderly patients with pulmonary Mycobacterium avium complex (pMAC) disease.

OBJECTIVES

To evaluate HQOL using the 36-Item Short-Form Health Survey and St George's Respiratory Questionnaire (SGRQ) and to investigate the predictors of HQOL changes among elderly patients with pMAC disease.

METHODS

This prospective cohort registry was conducted at Keio University Hospital, Tokyo, Japan, between May 2012 and July 2015 and included 84 patients with pMAC disease aged 75 years who had completed the HQOL questionnaire and 48 patients with pMAC disease who had been followed up and completed the HQOL questionnaire in cross-sectional and longitudinal analyses, respectively.

RESULTS

In cross-sectional analyses, elderly patients with pMAC disease had significantly lower role-physical, general health, vitality, social functioning, role-emotional and role/social component scores than the general Japanese elderly population. Analysis of covariance revealed that patients with cavitary lesions had significantly worse physical functioning and SGRQ scores (P < 0.05). Longitudinal analysis showed that under-treatment, short duration of disease and positive sputum smear at baseline were predictors of worse HQOL at 12 months.

CONCLUSIONS

Elderly patients with pMAC disease have reduced HQOL. Further large studies on HQOL are required to refine the use of this parameter in the treatment of these patients.

First report of hepatobiliary Mycobacterium avium infection developing obstructive jaundice in a patient with neutralizing anti-interferon-gamma autoantibodies

This study describes a patient who experienced hepatobiliary Mycobacterium avium infection associated with neutralizing anti–interferon gamma (IFN-γ) autoantibodies during treatment for disseminated M. avium disease. Hepatobiliary M. avium infection should be considered in jaundiced patients with neutralizing anti–IFN-γ autoantibodies, including those receiving antimycobacterial therapy for disseminated M. avium disease.

12-OH-17,18-Epoxyeicosatetraenoic acid alleviates eosinophilic airway inflammation in murine lungs

BACKGROUND

Asthma is characterized by airway inflammation and obstruction with eosinophil infiltration into the airway. Arachidonic acid, an omega-6 fatty acid, is metabolized into cysteinyl leukotriene with pro-inflammatory properties for allergic inflammation, whereas the omega-3 fatty acid eicosapentaenoic acid (EPA) and its downstream metabolites are known to have anti-inflammatory effects. In this study, we investigated the mechanism underlying the counter-regulatory roles of EPA in inflamed lungs.

METHODS

Male C57BL6 mice were sensitized and challenged by ovalbumin (OVA). After EPA treatment, we evaluated the cell count of Bronchoalveolar lavage fluid (BALF), mRNA expressions in the lungs by q-PCR, and the amounts of lipid mediators by liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based lipidomics. We investigated the effect of the metabolite of EPA by in vivo and in vitro studies.

RESULTS

Eicosapentaenoic acid treatment reduced the accumulation of eosinophils in the airway and decreased mRNA expression of selected inflammatory mediators in the lung. Lipidomics clarified the metabolomic profile in the lungs. Among EPA-derived metabolites, 12-hydroxy-17,18-epoxyeicosatetraenoic acid (12-OH-17,18-EpETE) was identified as one of the major biosynthesized molecules; the production of this molecule was amplified by EPA administration and allergic inflammation. Intravenous administration of 12-OH-17,18-EpETE attenuated airway eosinophilic inflammation through downregulation of C-C chemokine motif 11 (CCL11) mRNA expression in the lungs. In vitro, this molecule also inhibited the release of CCL11 from human airway epithelial cells stimulated with interleukin-4.

CONCLUSION

These results demonstrated that EPA alleviated airway eosinophilic inflammation through its conversion into bioactive metabolites. Additionally, our results suggest that 12-OH-17,18-EpETE is a potential therapeutic target for the management of asthma.

Annexin V decreases PS-mediated macrophage efferocytosis and deteriorates elastase-induced pulmonary emphysema in mice

Efferocytosis is believed to be a key regulator for lung inflammation in chronic obstructive pulmonary disease. In this study we pharmacologically inhibited efferocytosis with annexin V and attempted to determine its impact on the progression of pulmonary emphysema in mouse. We first demonstrated in vitro and in vivo efferocytosis experiments using annexin V, an inhibitor for phosphatidylserine-mediated efferocytosis. We then inhibited efferocytosis in porcine pancreatic elastase (PPE)-treated mice. PPE-treated mice were instilled annexin V intranasally starting from day 8 until day 20. Mean linear intercept (Lm) was measured, and cell apoptosis was assessed in lung specimen obtained on day 21. Cell profile, apoptosis, and mRNA expression of matrix metalloproteinases (MMPs) and growth factors were evaluated in bronchoalveolar lavage (BAL) cells on day 15. Annexin V attenuated macrophage efferocytosis both in vitro and in vivo. PPE-treated mice had a significant higher Lm, and annexin V further increased that by 32%. More number of macrophages was found in BAL fluid in this group. Interestingly, cell apoptosis was not increased by annexin V treatment both in lung specimens and BAL fluid, but macrophages from mice treated with both PPE and annexin V expressed higher MMP-2 mRNA levels and had a trend for higher MMP-12 mRNA expression. mRNA expression of keratinocyte growth factor tended to be downregulated. We showed that inhibited efferocytosis with annexin V worsened elastase-induced pulmonary emphysema in mice, which was, at least partly, attributed to a lack of phenotypic change in macrophages toward anti-inflammatory one.

Relationship between improved airflow limitation and changes in airway calibre induced by inhaled anticholinergic agents in COPD

BACKGROUND

Although airflow limitation improved by inhaled anticholinergic drugs varies among individuals with chronic obstructive pulmonary disease (COPD), the relationship between actual bronchodilation and improved pulmonary function and where in the lung such bronchodilation occurs remains unknown. A study was undertaken to determine the relationship between improved pulmonary function and changes in airway calibre at various sites in the airways in response to inhaled anticholinergic agents in patients with COPD using three-dimensional computed tomography (CT).

METHODS

CT scans were performed at deep inspiration and detailed pulmonary function tests before and 1 week after daily inhalations of tiotropium bromide in 15 patients with clinically stable COPD. The airway luminal area was examined at the third (segmental) to the sixth generations of eight bronchi in the right lung.

RESULTS

Bronchodilation was demonstrated by an overall average increase of 39% in the inner luminal area, and the mean (SE) forced expiratory volume in 1 s (FEV(1)) increased from 1.23 (0.11) l to 1.47 (0.13) l. The magnitude of bronchodilation was closely correlated with improved pulmonary function, particularly with that of FEV(1) (r = 0.843, p<0.001). Such correlations were significant at the fourth to the sixth generation but not at the third generation of bronchi, and the slope of the regression lines became steeper from the third to the sixth generation.

CONCLUSIONS

Inhaled anticholinergic agents induce overall bronchodilation which is in proportion to improvements in FEV(1) in patients with COPD. Bronchodilation at the distal rather than the proximal airways is the determinant of functional improvement.

Functional single nucleotide polymorphisms of the CCL5 gene and nonemphysematous phenotype in COPD patients

It was previously reported that the gain-of-function -28 guanine allele of the promoter single nucleotide polymorphism (SNP; cytosine to guanine substitution of nucleotide -28 (-28C>G)) in the CC chemokine ligand 5 gene (CCL5) was associated with susceptibility to late-onset asthma in patients who developed asthma at age > or =40 yrs. The clinical diagnosis of chronic obstructive pulmonary disease (COPD) includes emphysema and small airway disease, and upregulation of CCL5 has been described in the airways of patients with COPD. It was hypothesised that CCL5 has a genetic impact upon the variable expression of emphysema in patients with COPD. Patients with COPD were studied (n = 267). All of the patients underwent pulmonary high-resolution computed tomography (CT), and visual scoring (CT score) was performed to determine emphysema severity. Three SNPs of CCL5 were genotyped, including -403G>A, -28C>G and 375T>C. A significant difference was found in CT score according to CCL5 genotype; the -28G allele was inversely associated with CT score. When the analysis was confined to 180 patients with bronchial reversibility of <15%, even stronger evidence for this association was noted. Functional single nucleotide polymorphisms in the CC chemokine ligand 5 gene were associated with milder emphysema. Together with previous findings, the present study may identify the CC chemokine ligand 5 gene as part of a common pathway in the pathogenesis of late-onset asthma and chronic obstructive pulmonary disease with milder emphysema.

Long term smoking with age builds up excessive oxidative stress in bronchoalveolar lavage fluid

BACKGROUND

Epithelial lining fluid plays a critical role in protecting the lung from oxidative stress, in which the oxidised status may change by ageing, smoking history, and pulmonary emphysema.

METHODS

Bronchoalveolar lavage (BAL) was performed on 109 young and older subjects with various smoking histories. The protein carbonyls, total and oxidised glutathione were examined in BAL fluid.

RESULTS

By Western blot analysis, the major carbonylated protein in the BAL fluid was sized at 68 kDa, corresponding to albumin. The amount of carbonylated albumin per mg total albumin in BAL fluid was four times higher in older current smokers and three times higher in older former smokers than in age matched non-smokers (p<0.0001, p=0.0003, respectively), but not in young smokers. Total glutathione in BAL fluid was significantly increased both in young (p=0.006) and older current smokers (p=0.0003) compared with age matched non-smokers. In contrast, the ratio of oxidised to total glutathione was significantly raised (72%) only in older current smokers compared with the other groups. There was no significant difference in these parameters between older smokers with and without mild emphysema.

CONCLUSIONS

Oxidised glutathione associated with excessive protein carbonylation accumulates in the lung of older smokers with long term smoking histories even in the absence of lung diseases, but they are not significantly enhanced in smokers with mild emphysema.

Role of macrophage migration inhibitory factor in ovalbumin-induced airway inflammation in rats

Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine that reportedly counteracts the anti-inflammatory effect of endogenous glucocorticoids. There have only been a few reports that demonstrate a potential link between MIF and bronchial asthma. In an attempt to further clarify the precise role of MIF in asthma, the present authors examined the effect of anti-MIF antibody (Ab) on airway inflammation and airway hyperresponsiveness in an ovalbumin-immunised rat asthma model. Actively immunised Brown Norway rats received ovalbumin inhalation with or without treatment of anti-MIF Ab. The levels of MIF in bronchoalveolar lavage fluid were significantly elevated after the ovalbumin challenge. An immunohistochemical study revealed positive immunostaining for MIF in bronchial epithelium, even in nonsensitised rats, and the MIF staining in bronchial epithelium was enhanced after the ovalbumin challenge. Anti-MIF Ab significantly decreased the number of total cells, neutrophils and eosinophils in the bronchoalveolar lavage fluid of the ovalbumin-challenged rats, and also attenuated the ovalbumin-induced airway hyperresponsiveness to ovalbumin and methacholine. However, anti-MIF Ab did not affect the level of serum ovalbumin-specific IgE, suggesting that anti-MIF Ab did not suppress immunisation itself. The results indicate that macrophage migration inhibitory factor plays a crucial role in airway inflammation and airway hyperresponsiveness in asthma.

Decrease of vascular endothelial growth factor in macrophages from long-term smokers

Vascular endothelial growth factor (VEGF), a survival factor for endothelial cells and a promoter of angiogenesis, is reportedly expressed in alveolar macrophages (AMs). To investigate whether long-term smoking with age affects VEGF expression in AMs, bronchoalveolar lavage (BAL) was performed on 18 young and 23 older volunteers with various smoking histories. The expressions of VEGF and its functional receptor, fms-like tyrosine kinase (Flt)-1, were quantified in AMs by real-time RT-PCR and, further, the level of VEGF in BAL fluid was determined by ELISA. VEGF mRNA in AMs demonstrated a 1.8-fold reduction in current smokers compared with nonsmokers in older subjects and, furthermore, a 1.5-fold downregulation in those with emphysema, although there was no difference between current smokers and nonsmokers among the young subjects. The downregulation in total VEGF mRNA was supported by the substantial reduction of VEGF121 and VEGF165 isoforms. However, in contrast, Flt-1 mRNA did not differ within the older groups, whereas it was upregulated in young current smokers compared with age-matched nonsmokers. VEGF in BAL fluid is significantly decreased in current smokers compared with nonsmokers, regardless of their age. In conclusion, these data imply that the biological availability of vascular endothelial growth factor in alveolar macrophages is impaired in older current smokers with long-term smoking histories.

Effects of ageing and smoking on SP-A and SP-D levels in bronchoalveolar lavage fluid

Surfactant protein (SP)-A and SP-D are collagen-like glycoproteins that are synthesised in the distal pulmonary epithelium. This study examined the effects of ageing and long-term smoking on SP-A and SP-D in the lungs. The possible links to the development of pulmonary emphysema were also investigated. Sequential lavage was performed in young and middle-aged or elderly nonsmokers and asymptomatic current smokers with various smoking histories. Middle-aged or elderly smokers were further categorised according to the presence of emphysema by high-resolution computed tomography. Levels of SP-A and SP-D in bronchial lavage (BL) fluid and in bronchoalveolar lavage (BAL) fluid were quantified by ELISA. Significant decreases in SP-A were seen with age in nonsmokers in BL fluid, but not in BAL fluid. Middle-aged or elderly smokers with emphysema had lower levels of SP-A in both BL and BAL fluids when compared with young subjects, and in BL fluid when compared with middle-aged or elderly smokers without emphysema. SP-D did not change with age alone, however, it was decreased in middle-aged or elderly smokers when compared with similarly aged nonsmokers. In conclusion, surfactant protein-A may decrease with age alone or due to the cumulative effects of long-term smoking and development of emphysema, while surfactant protein-D decreases due to long-term smoking.

Role of secretory leukocyte protease inhibitor in the development of subclinical emphysema

Secretory leukocyte protease inhibitor (SLPI) is a potent inhibitor of human leukocyte elastase. In some chronic airway diseases, the level of SLPI is decreased in sputum, leading to the continuation of neutrophil inflammation. In this study, the role of SLPI in subclinical pulmonary emphysema was examined. Sequential bronchoalveolar lavage was performed in an attempt to separately evaluate the levels of SLPI in the large airways and in the peripheral airways for two groups of smokers. One group had subclinical emphysema by computed-tomography scans and one group did not. SLPI localized in alveolar macrophages (AM) was also assessed. The level of SLPI was significantly elevated in the peripheral airways from the subjects with emphysema compared to those without emphysema (1589.2+/-353.9 versus 729.1+/-31.0 ng x mL(-1)), although it was similar in the large airways (3442.3+/-499.6 versus 2535.7+/-578.8 ng x mL(-1)). There was a trend for higher amount of SLPI to be released from AM in subjects with subclinical emphysema, although this did not reach statistical significance. In conclusion, there is compensatory upregulation of secretory leukocyte protease inhibitor in peripheral airways in subclinical pulmonary emphysema, which is in sharp contrast to the decreased level of secretory leukocyte protease inhibitor reported in some chronic airway diseases.

Increased levels of interleukin-8 in BAL fluid from smokers susceptible to pulmonary emphysema

BACKGROUND

It has previously been shown that smokers with computed tomographic (CT) evidence of subclinical emphysema have signs of neutrophil activation, despite having no appreciable increase in the number of neutrophils in their bronchoalveolar lavage (BAL) fluid.

METHODS

The levels of the following chemoattractants in BAL fluid from 61 community based older volunteers classified into four groups according to current smoking status and the presence or absence of emphysema were determined: interleukin 8 (IL-8), epithelial neutrophil activating protein 78 (ENA-78) and leukotriene B(4) (LTB(4)) which are primarily chemotactic for neutrophils; monocyte chemoattractant protein 1 (MCP-1) and macrophage inflammatory protein-1alpha (MIP-1alpha) which are predominantly chemotactic for mononuclear leucocytes.

RESULTS

Of the five chemoattractants studied, only the level of IL-8 in BAL fluid clearly distinguished between subjects with and without emphysema among current smokers (median values 34.7 and 12.2 pg/ml, respectively, p<0.01). In addition, the levels of IL-8 and neutrophil elastase-alpha(1) protease inhibitor complex in BAL fluid were significantly correlated (r=0.65, p<0.01). There was no difference in either the release of IL-8 from cultured alveolar macrophages at 24 hours or the expression of IL-8 messenger RNA of alveolar macrophages in the two groups of current smokers with and without emphysema.

CONCLUSION

An accelerated response of IL-8 to chronic smoking is a factor that characterises those smokers who are susceptible to pulmonary emphysema, although the cellular source of IL-8 remains to be determined.

Tolerance for ATP-insensitive K(ATP) channels in transgenic mice

To examine the role of sarcolemmal K(ATP) channels in cardiac function, we generated transgenic mice expressing GFP-tagged Kir6.2 subunits with reduced ATP sensitivity under control of the cardiac alpha-myosin heavy chain promoter. Four founder mice were isolated, and both founders and progeny were all apparently normal and fertile. Electrocardiograms from conscious animals also appeared normal, although mean 24-hour heart rate was approximately 10% lower in transgenic animals compared with littermate controls. In excised membrane patches, K(ATP) channels were very insensitive to inhibitory ATP: mean K(1/2) ([ATP] causing half-maximal inhibition) was 2.7 mmol/L in high-expressing line 4 myocytes, compared with 51 micromol/L in littermate control myocytes. Counterintuitively, K(ATP) channel density was approximately 4-fold lower in transgenic membrane patches than in control. This reduction of total K(ATP) conductance was confirmed in whole-cell voltage-clamp conditions, in which K(ATP) was activated by metabolic inhibition. K(ATP) conductance was not obvious after break-in of either control or transgenic myocytes, and there was no action potential shortening in transgenic myocytes. In marked contrast to the effects of expression of similar transgenes in pancreatic beta-cells, these experiments demonstrate a profound tolerance for reduced ATP sensitivity of cardiac K(ATP) channels and highlight differential effects of channel activity in the electrical activity of the 2 tissues.

Laser capture microdissection and real-time reverse transcriptase/ polymerase chain reaction of bronchiolar epithelium after bleomycin

Terminal airways are affected in many lung diseases and toxic inhalations. To elucidate the changes in terminal airways in these diverse situations it will be helpful to profile and quantify gene expression in terminal bronchiolar epithelium. We used laser capture microdissection (LCM) to collect terminal bronchiolar epithelial cells from frozen sections of lungs of mice subjected to intratracheal bleomycin. The RNA from these cells was used for analysis of select messenger RNAs (mRNAs) by quantitative real-time polymerase chain reaction (PCR). In parallel, we used real-time PCR to analyze mRNAs in whole-lung homogenates prepared from other mice given intratracheal bleomycin. We found reductions of Clara cell-specific protein and keratinocyte growth factor receptor mRNAs in both terminal bronchiolar epithelium and whole-lung homogenates 7 d after bleomycin. In contrast, terminal bronchiolar epithelial transforming growth factor (TGF)-alpha mRNA was reduced but whole-lung TGF-alpha mRNA was not changed, whereas terminal bronchiolar epithelial epidermal growth factor (EGF) receptor mRNA was not changed but whole-lung EGF receptor was reduced. We conclude that LCM can isolate terminal bronchiolar epithelial cells for studies of cell-specific gene expression by quantitative real-time PCR, and that cell-specific gene expression in terminal bronchiolar epithelium is not necessarily reflected in analysis of whole-lung gene expression.

Decline in FEV(1) in community-based older volunteers with higher levels of neutrophil elastase in bronchoalveolar lavage fluid

BACKGROUND

Neutrophil elastase (NE) is thought to be one of the key proteinases in the development of chronic obstructive pulmonary disease (COPD). Previously, we have shown that the NE-alpha1-proteinase inhibitor (NE-alpha1PI) complex in bronchoalveolar lavage (BAL) fluid was markedly elevated in asymptomatic smokers who had subclinical emphysema on CT scans. We proposed that excessive NE-alpha1PI complex in BAL fluid was a factor which might differentiate smokers who were developing emphysema from others.

OBJECTIVE

In this study, we addressed the question of whether elevated levels of the NE-alpha1PI complex in BAL fluid are linked to the accelerated decline in pulmonary functions in those subjects.

METHODS

We conducted a follow-up study to analyze the decline in FEV(1) for 4.3 years on average for 26 community-based volunteers who had received pulmonary function tests, CT scans and BAL. The levels of the NE-alpha1PI complex in BAL fluid and in plasma was measured.

RESULTS

Neither pulmonary function measurements nor the presence of emphysema on CT scans could predict the decline in FEV(1). The number of inflammatory cells in BAL fluid was also not an indicator of progression. By contrast, subjects with higher levels of the NE-alpha1PI complex in BAL fluid had a significantly accelerated decline in FEV(1) compared to those with lower levels.

CONCLUSION

These data seem to support the hypothesis that NE in the lung is related to the onset and/or progression of COPD.

Gelatinase B is required for alveolar bronchiolization after intratracheal bleomycin

Increased expression of matrix metalloproteinases, particularly gelatinase B (MMP-9), has been described in the lungs in pulmonary fibrosis. Intratracheal bleomycin is often used experimentally to produce lesions resembling human fibrosing alveolitis. To assess the role of gelatinase B in bleomycin-induced fibrosing alveolitis, we instilled bleomycin intratracheally into gelatinase B-deficient mice and gelatinase B+/+ littermates. Twenty-one days after bleomycin the two groups of mice were indistinguishable in terms of pulmonary histology and total lung collagen and elastin. However, the lungs of gelatinase B-deficient mice showed minimal alveolar bronchiolization, whereas bronchiolization was prominent in the lungs of gelatinase B+/+ mice. Gelatinase B was identified immunohistochemically in terminal bronchiolar cells and bronchiolized cells 7 and 14 days after bleomycin in gelatinase B+/+ mice, and whole lung gelatinase B mRNA was increased at the same times. Many bronchiolized cells displayed Clara cell features by electron microscopy. Some bronchiolized cells stained with antibody to helix transcription factor 4, a factor associated with the ciliated cell phenotype. Thus, fibrosing alveolitis develops after intratracheal bleomycin irrespective of gelatinase B. However, gelatinase B is required for alveolar bronchiolization, perhaps by facilitating migration of Clara cells and other bronchiolar cells into the regions of alveolar injury.

Gelatinase B (MMP-9) is not essential in the normal kidney and does not influence progression of renal disease in a mouse model of Alport syndrome

Matrix metalloproteinases are matrix degrading enzymes implicated in many biological processes, including development and inflammation. Gelatinase B (gelB; also known as MMP-9) is expressed in the kidney and is hypothesized to be involved in basement membrane remodeling and in preventing pathogenic accumulation of extracellular matrix in the kidney. Inhibition of gelB activity in metanephric organ culture disrupts branching morphogenesis of the ureteric bud, suggesting that gelB plays a role in kidney development in vivo. We studied kidneys of gelB-deficient mice to search for developmental, histological, molecular, ultrastructural, and functional defects. Surprisingly, no differences between gelB-/- and control kidneys were detected, and renal function was normal in gelB mutants. In addition, gelB-/- embryonic kidneys developed normally in organ culture. Gelatinase B-deficient mice were bred with Col4a3-/- mice, a model for Alport syndrome, to determine whether gelB influences the progression of glomerulonephritis. This is an important question, as it has been hypothesized that proteases are involved in damaging Alport glomerular basement membrane. However, the presence or absence of gelB did not affect the rate of progression of renal disease. Thus, gelB does not have a discernible role in the normal kidney and gelB is not involved in the progression of glomerulonephritis in a mouse model of Alport syndrome.

[A comparative study of computed tomographic techniques for the detection of emphysema in middle-aged and older patient populations]

Helical-scan computed tomography (CT) is now widely utilized as a mass screening procedure for lung cancer. By adding 3 slices of high-resolution CT (HRCT) to the standard screening procedure, we were able to compare the efficacy of helical-scan CT and HRCT in detecting pulmonary emphysema. Additionally, the prevalence of emphysema detected by HRCT was examined as a function of patient age and smoking history. The subjects (106 men and 28 women) were all community-based middle-aged and older volunteers who participated in a mass lung cancer screening program. Based on visual assessments of the CT films, emphysema was detected in 29 subjects (22%) by HRCT, but in only 4 (3%) by helical-scan CT. Although the prevalence of emphysema was higher among subjects with a higher smoking index, no correlations with age were observed. We concluded that the efficacy of helical scan CT in detecting pulmonary emphysema can be significantly improved with the inclusion of 3 slices of HRCT, and confirmed that cigarette smoking is linked to the development of pulmonary emphysema.

Diastolic potentials in verapamil-sensitive ventricular tachycardia: true potentials or bystanders of the reentry circuits?

BACKGROUND

Diastolic potentials (DP) are reported to be recorded in intracardiac electrograms during verapamil-sensitive ventricular tachycardia (VT) in which QRS complexes show complete right bundle branch block with a superior axis. The purpose of this study was to ascertain whether the DP recorded in the endocardial mapping during VT reflects the activation of the VT circuit.

METHODS AND RESULTS

The study group consisted of 16 men and 2 women. The earliest activation site (EA site) was determined and the DP was recorded in the endocardial mapping during VT. We evaluated the response of the cycle length of VT, the interval between the ventricular activation and the DP (V-DP), and the interval between the DP and the ventricular activation (DP-V) to intravenous verapamil. Radiofrequency current was delivered to the EA site, the site where the DP was recorded, and the site where the DP and the Purkinje fiber potential of the left bundle branch (LB) were simultaneously recorded. In 15 patients, the DP was recorded in the wide posterior fascicle region of the LB. After verapamil, the cycle length of VT, the V-DP, and the DP-V were prolonged from 365 +/- 53 to 490 +/- 65, 315 +/- 30 to 368 +/- 30, and 50 +/- 27 to 123 +/- 36 ms, respectively, in 6 patients. The LB was recorded in all patients and the DP was recorded preceding the LB in 12 patients. VT was successfully ablated at the site where the DP and the LB were simultaneously recorded in all these patients. Ablation at the other sites failed.

CONCLUSIONS

Radiofrequency ablation at the site where the DP was simultaneously recorded preceding the LB completely abolished the verapamil-sensitive VT. The DP recorded with the LB simultaneously might reflect the slow conduction zone activity of the reentry circuit located within the Purkinje fiber network.

Neutrophil emigration in the lungs, peritoneum, and skin does not require gelatinase B

Polymorphonuclear leukocytes (PMN) release gelatinase B in response to variable stimuli. Gelatinase B degrades basement membrane components in vitro, and inhibition of matrix metalloproteinase activity blunts PMN migration through a prototype basement membrane (Matrigel) and amnionic membranes. Accordingly, it has been speculated that gelatinase B is necessary for PMN emigration. To test this hypothesis we induced acute inflammation in the lungs, peritoneum, and skin in mice with a null mutation of the gelatinase B gene (gelatinase B-/-) and littermate controls (gelatinase B+/+). At 3, 6, 12, and 24 h after intratracheal instillation of LPS, the emigration of PMN in the lung, as determined by PMN in bronchoalveolar lavage fluid, was similar in gelatinase B-/- and gelatinase B+/+ mice. The number of PMN in the peritoneal cavity 4 h after thioglycollate-induced peritonitis was also comparable in gelatinase B-/- and gelatinase B+/+ mice. At 4 h after an intradermal injection of interleukin-8, numerous PMN were present extravascularly in the dermis in both gelatinase B-/- and gelatinase B+/+ mice and the myeloperoxidase activities of the skin at the injection sites were indistinguishable between the two types of mice. PMN from gelatinase B-/- mice migrated through Matrigel in response to zymosan-activated serum with the same efficiency as did PMN from gelatinase B+/+ mice. In vitro, gelatinase B-/- PMN killed Staphylococcus aureus and Klebsiella pneumoniae as effectively as did PMN from gelatinase B+/+ mice. These findings indicate that gelatinase B is not required for PMN emigration, and suggest that the antibacterial function of PMN is preserved despite gelatinase B deficiency.

Neutrophil granule proteins in bronchoalveolar lavage fluid from subjects with subclinical emphysema

Evidence for the contribution of neutrophils to the pathogenesis of pulmonary emphysema is not convincing. We evaluated neutrophil involvement in subclinical pulmonary emphysema by measuring human neutrophil lipocalin (HNL) and two matrix metalloproteinases, gelatinase B (MMP-9) and neutrophil collagenase (MMP-8), in bronchoalveolar lavage fluid (BALF) from 65 community-based older volunteers. HNL is a recently isolated 24-kD protein secreted from secondary granules of activated neutrophils. Despite no appreciable increase in the number of neutrophils, the level of HNL was significantly increased in BALF from subjects with emphysema evidenced by computed tomography regardless of current smoking, as compared with smokers without emphysema. The levels of MMP-9 and MMP-8 were also significantly higher in current smokers with emphysema than in those without emphysema. The appearance of a 130-kD HNL/MMP-9 complex on gelatin zymography and HNL immunoblot indicated neutrophils to be a significant source of MMP-9 in the subjects' BALF. In a 24-h culture medium of alveolar macrophages, only a latent form of MMP-9 was detected, and there was no difference in the level of MMP-9 between the groups. These data provide further evidence for neutrophil involvement in subclinical pulmonary emphysema.

A functional granulocyte colony-stimulating factor receptor is required for normal chemoattractant-induced neutrophil activation

Granulocyte colony-stimulating factor (G-CSF) is a hematopoietic growth factor that is widely used to treat neutropenia. In addition to stimulating polymorphonuclear neutrophil (PMN) production, G-CSF may have significant effects on PMN function. Because G-CSF receptor (G-CSFR)-deficient mice do not have the expected neutrophilia after administration of human interleukin-8 (IL-8), we examined the effect of the loss of G-CSFR on IL-8-stimulated PMN function. Compared with wild-type PMNs, PMNs isolated from G-CSFR-deficient mice demonstrated markedly decreased chemotaxis to IL-8. PMN emigration into the skin of G-CSFR-deficient mice in response to IL-8 was also impaired. Significant chemotaxis defects were also seen in response to N-formyl-methionyl-leucyl-phenylalanine, zymosan-activated serum, or macrophage inflammatory protein-2. The defective chemotactic response to IL-8 does not appear to be due to impaired chemoattractant receptor function, as the number of IL-8 receptors and chemoattractant-induced calcium influx, actin polymerization, and release of gelatinase B were comparable to those of wild-type PMNs. Chemoattractant-induced adhesion of G-CSFR-deficient PMNs was significantly impaired, suggesting a defect in beta2-integrin activation. Collectively, these data demonstrate that selective defects in PMN activation are present in G-CSFR-deficient mice and indicate that G-CSF plays an important role in regulating PMN chemokine responsiveness.

Cysteine proteinases and cystatin C in bronchoalveolar lavage fluid from subjects with subclinical emphysema

This study examined the role of cysteine proteinases and their inhibitor in the development of emphysema in comparison with neutrophil elastase (NE) complexed with alpha1-protease inhibitor (NE-alpha1-PI), which was previously demonstrated to be increased in bronchoalveolar lavage (BAL) fluid from subjects with subclinical emphysema. Eight nonsmokers and 31 current smokers with (n=17) and without (n=14) emphysema, as evidenced by lung computed tomographic scans, were studied. The concentrations of immunologically detected cathepsin L and cystatin C, but not cathepsin B, were significantly increased in BAL fluid from the smokers with emphysema compared with those without emphysema, although the activity of cathepsin L, measured using a synthetic substrate and cathepsin L, released from cultured alveolar macrophages at 24 h, did not show any significant difference between the two groups. When comparison was made only for the subjects aged <60 yrs, the difference between the two groups disappeared for cathepsin L, but remained for NE-alpha1-PI. There was no significant correlation between the level of cathepsin L and that of NE-alpha1-PI in BAL fluid from the subjects with emphysema. In conclusion, increased levels of cathepsin L and cystatin C were demonstrated in bronchoalveolar lavage fluid from subjects with subclinical emphysema. However, the roles of cathepsin L and neutrophil elastase in the development of emphysema may vary between subjects and between the young and the old.

The efficacy of radiofrequency catheter ablation for the treatment of ventricular tachycardia associated with cardiomyopathy

We performed radiofrequency catheter ablation (RF ablation) for ventricular tachycardia (VT) in 2 patients with dilated cardiomyopathy (DCM) and 1 patient with arrhythmogenic right ventricular dysplasia (ARVD). Patient 1 had incessant VT associated with DCM. RF ablation was performed where diastolic potentials were recorded and concealed entrainment was demonstrated. VT was terminated by RF ablation. Patient 2 had drug-resistant VT associated with ARVD. RF ablation was performed where perfect pace-mapping was obtained during sinus rhythm, diastolic potentials were recorded and concealed entrainment was demonstrated. VT was terminated by RF ablation. Patient 3 had 2 morphologically distinct VTs associated with DCM. The target for RF ablation was 1 of the 2, which was a drug-resistant type. Perfect pace mapping was obtained where delayed potentials were recorded. As the current strength of pacing was reduced, the QRS complex configuration switched to the other type. This site was thought to be the common slow conduction zone for the re-entry circuit of the 2 types and RF ablation was performed at this site. In these 3 cases, VT did not recur after ablation. RF ablation is effective for the treatment of VT associated with cardiomyopathy.

Topoisomerase II alpha content and topoisomerase II catalytic activity cannot explain drug sensitivities to topoisomerase II inhibitors in lung cancer cell lines

PURPOSE

Topoisomerase II alpha content, topoisomerase II catalytic activity and drug sensitivities to the topoisomerase II inhibitors, doxorubicin and etoposide, were examined in a panel of 14 unselected human lung cancer cell lines in order to determine the relationship between topoisomerase II and drug sensitivities to the topoisomerase II inhibitors.

METHODS

Drug sensitivities were determined using a microculture tetrazolium assay. The topoisomerase II alpha levels were determined by Western blot analysis and the topoisomerase II catalytic activity was determined using a decatenation assay of kinetoplast DNA, using nuclear protein from cells of each cell line.

RESULTS

Drug sensitivity tests revealed that small-cell lung cancer (SCLC) cell lines were more sensitive to drugs than non-small-cell lung cancer (NSCLC) cell lines. The relative topoisomerase II alpha levels and relative topoisomerase II catalytic activity from SCLC cell lines (mean +/- SD 0.89 +/- 0.54 and 5.3 +/- 3.4, respectively) were slightly higher than those from NSCLC cell lines (0.78 +/- 0.56 and 4.0 +/- 2.8, respectively), but the differences were not statistically significant, and not sufficient to account for the variation in drug sensitivities. Moreover, no clear association was observed between the topoisomerase II alpha levels or the topoisomerase II catalytic activity and drug sensitivities in the cell lines studied.

CONCLUSIONS

These findings suggest that the difference in drug sensitivities to doxorubicin and etoposide in human lung cancer cell lines might not be explainable by the topoisomerase II alpha levels and topoisomerase II catalytic activity. Moreover, our results suggest that the topoisomerase II alpha levels and topoisomerase II catalytic activity may play a minor role in the determination of clinical drug resistance of human lung cancers.

[Neutrophil elastase and elastin-derived peptides in BAL fluid and emphysematous changes on CT scans]

We examined the relationship between neutrophil elastase, elastin-derived peptides in bronchoalveolar lavage (BAL) fluid, and the development of pulmonary emphysema. The level of neutrophil elastase was higher in asymptomatic current smokers with emphysematous changes on computed tomographic scans than in current smokers without emphysematous changes, and was found to be correlated with the level of elastin-derived peptides in BAL fluid. Subjects with high levels of neutrophil elastase in BAL fluid had faster annual declines in FEV1. We conclude that the level of neutrophil elastase in BAL fluid can be used to differentiate asymptomatic cigarette smokers who are at risk for pulmonary emphysema from those who are not.

A case of adenosine-sensitive ventricular tachycardia in a very elderly male

The best-known type of adenosine-sensitive ventricular tachycardia is idiopathic and of right ventricular outflow origin; however, there is little information about other types of adenosine-sensitive ventricular tachycardia. Idiopathic adenosine-sensitive ventricular tachycardia is common in the young. An 87-year-old man with ventricular tachycardia was admitted to our hospital. His ventricular tachycardia was sensitive to adenosine triphosphate, edrophonium, verapamil, and Valsalva's maneuver. He had experienced no anginal episodes. His ventricular tachycardia was thought to be idiopathic. We report this very rare case of adenosine-sensitive ventricular tachycardia, which was not derived from the right ventricular outflow tract, in a very elderly male.

Elastin-derived peptides and neutrophil elastase in bronchoalveolar lavage fluid

To evaluate effects of current smoking on the breakdown of lung elastin, we measured levels of elastin-derived peptides (EDP) in unconcentrated bronchoalveolar lavage (BAL) fluid from 42 community-based older asymptomatic volunteers (60 +/- 11 yr [mean +/- SD]) and examined the relationships of the concentrations of EDP with immunologically detected neutrophil elastase (NE) bound with alpha(1)-proteinase inhibitor and with esterolytic activity against the NE-sensitive synthetic substrate, methoxysuccinyl-alanyl-alanyl-prolyl-valyl paranitroanilide (MEOSAAPVNA). The measurement of EDP levels was carried out by an indirect, competitive ELISA, using a sheep IgG fraction generated against insoluble human lung elastin as a primary antibody. EDP concentrations were significantly elevated in current smokers (n = 24) compared with age-matched noncurrent smokers (n = 18) (29.9 +/- 3.5 [mean +/- SE] versus 17.0 +/- 1.8 ng/mg BAL fluid albumin, p < 0.01). We found weak but significant correlations of EDP levels with NE-alpha(1)-proteinase inhibitor complex (r = 0.38, p < 0.05) and with the esterolytic activity against the NE-sensitive synthetic substrate in BAL fluid (r = 0.65, p < 0.001). In addition, EDP levels in BAL fluid had a significant positive relationship with plasma cotinine concentrations (r = 0.53, p < 0.001), though not with pack-years of smoking (r = 0.1, NS). These data provide further evidence that the concentrations of EDP increase in BAL fluid from current smokers compared with noncurrent smokers and that enhanced breakdown of the lung elastin is associated with the increased load of NE in the lung.

Pulmonary function is diminished in older asymptomatic smokers and ex-smokers with low attenuation areas on high-resolution computed tomography

OBJECTIVES

The relation between pulmonary function and low attenuation areas (LAAs) on high-resolution computed tomography (HRCT) is not clear in subclinical pulmonary emphysema. Accordingly we examined pulmonary function and HRCT in asymptomatic community-based volunteers.

DESIGN

The existence of LAAs on CT was evaluated independently by three respiratory physicians who were blind to the pulmonary function test data and smoking histories of the subjects. The LAA grade was assessed by a visual scoring method from 0 to 5, and the individual LAA score and the values of pulmonary function tests were compared.

PARTICIPANTS

57 subjects aged from 32 to 82 years [mean 62 +/- (SD) 11] years were enrolled in the study.

RESULTS

LAAs were found in 20 of the 49 subjects who were current or ex-smokers but in none of the 8 who never smoked. LAAs observed were mostly less than 25% of the total areas of the lungs. Although all mean values were within normal limits, the forced expiratory volume in 1 s (%pred), maximal expiratory flow at 50% of forced vital capacity (%pred), diffusing capacity of the lungs for carbon monoxide (DLCO; %pred) and diffusing capacity for carbon monoxide per unit alveolar volume (DLCO/VA; %pred) were all significantly less in those with LAAs than in those without LAAs. There was also a significant tendency for DLCO %pred and DLCO/VA %pred to decrease as the LAA scores increased.

CONCLUSION

Those who have LAAs on CT have a small but significant deterioration in pulmonary function tests even if the LAAs observed are minimal or mild in degree. Longitudinal studies will be necessary to determine whether LAAs on CT identify the subjects who will develop airflow obstruction over time.

Excessive neutrophil elastase in bronchoalveolar lavage fluid in subclinical emphysema

In an attempt to further evaluate the role of neutrophil elastase (NE) in the development of emphysema, we examined the immunologic quantity of NE bound to alpha 1-protease inhibitor (PI), the NE inhibitory activity, and the molecular pattern of alpha 1-PI in unconcentrated bronchoalveolar lavage fluid (BALF) supernatant from 36 community-based older volunteers. They were classified into three groups: 10 current smokers with low attenuation areas (LAAs) on the lung computed tomography (CT) scans who were considered to have subclinical emphysema, 13 current smokers who had a comparable smoking history but no LAA, and 13 noncurrent smokers without LAA. The concentration of NE-alpha 1-PI complex was significantly increased in the subjects with subclinical emphysema when compared not only with the noncurrent smokers (0.52 +/- 0.10 versus 0.21 +/- 0.03 SEM micrograms/mg albumin, p < 0.01) but also with the LAA(-) current smokers (0.52 +/- 0.10 versus 0.23 +/- 0.07 SEM micrograms/mg albumin, p < 0.01). NE inhibitory activity measured by a spectrophotometric method using methoxysuccinyl-alanyl-alanyl-prolyl-valyl-paranitroanilide did not show any significant difference between the two groups of current smokers. There was no difference in the pattern or density of native and proteolysed alpha 1-PI bands between the three groups by Western blotting. We conclude that NE-alpha 1-PI complex in BALF is a factor that may differentiate smokers who are potentially developing emphysema from those who are not.

A case of familial ventricular tachycardia

Ventricular tachycardia was noted in 4 members of the same family. One showed diffuse hypokinesis of the left ventricle by echocardiography and left ventriculography, 2 showed progressive left ventricular dysfunction and 1 showed regional perfusion defects of the left ventricle shown by thallium scintigraphy. One patient was diagnosed as dilated cardiomyopathy. Although no definitive cause of the left ventricular disturbance was identified in the 3 other patients, they may have all been dilated cardiomyopathy.

Neutrophil elastase associated with alveolar macrophages from older volunteers

We focused on the role of neutrophil elastase (NE) in alveolar macrophages (AMs), and evaluated the esterolytic activity using an NE-sensitive substrate, methoxysuccinyl-alanyl-alanyl-prolyl-valyl paranitroanilide (MEOSAAPVNA) in AMs from 36 older healthy volunteers (61 +/- 2 yr mean age +/- standard error) and examined the relationship to chronic effects of cigarette smoking and also to the presence of low attenuation areas (LAAs) on the computed tomographic (CT) scans. The AMs from the subjects with LAAs showed significantly higher activity than those from the current smokers without LAA (1.16 +/- 0.40 versus 0.34 +/- 0.07 nM, respectively, p < 0.05). Although the study of inhibitory profile revealed that the esterolytic activity could not be attributed to NE alone, the NE activity seemed to dominate in AMs at least from some who had higher esterolytic activity. We then examined the releasability of NE from cultured AMs in 10 subjects. The immunologic NE complex with alpha 1-protease inhibitor (alpha 1-PI) was released significantly higher in the LAA(+) group than in the LAA(-) group (17.4 +/- 6.5 versus 1.8 +/- 0.6 micrograms/L, respectively, p < 0.05). These data suggest that NE in AMs may play a role in the development of emphysematous changes in susceptible smokers.