POS1238 GLUCOCORTICOIDS, RITUXIMAB AND THE PRESENCE OF INTERSTITIAL LUNG DISEASE ARE ASSOCIATED WITH POOR OUTCOMES OF THE SARS-COV-2 INFECTION IN PATIENTS WITH RHEUMATOID ARTHRITIS: DATA FROM THE NATIONAL REGISTRY SAR-COVID

Background

High disease activity, treatment with glucocorticoids (GC) and rituximab (RTX), have been related to worse outcomes of COVID-19.

Objectives

To assess the clinical characteristics and severity of the SARS-CoV-2 infection in patients with rheumatoid arthritis (RA) included in the SAR-COVID registry and to identify factors associated with poor outcomes.

Methods

SAR-COVID is a national, longitudinal and observational registry. Patients of ≥18 years old, with diagnosis of RA (ACR-EULAR criteria 2010) who had confirmed SARS-CoV-2 infection (RT-PCR or positive serology) were included between 13-8-20 and 31-7-21. Sociodemographic and clinical data, comorbidities, disease activity and treatment at the moment of the SARS-CoV-2 infection were collected. Additionally, infection symptoms, complications, medical interventions and treatments for COVID-19 were registered. Infection severity was assessed using the WHO-ordinal scale (WHO-OS)1. A cut-off value of ≥5 identified patients with severe COVID-19 and those who died.

Statistical analysis: Descriptive statistics. Chi2 or Fischer test, Student T test or Mann-Whitney and Kruskal Wallis or ANOVA, as appropriate. Multiple logistic regression model.

Results

A total of 801 patients were included, with a mean age of 53.1 ± 12.9 years, most of them were female (84.5%) and the median (m) disease duration was 8 years (IQR 4-14). One third were in remission and 46.4% had comorbidities, being the most frequent, hypertension (26.9 %), dyslipidemia (13.5 %), obesity (13.4 %) and diabetes (8.9%). Moreover, 3.2% had interstitial lung disease (ILD) associated with RA. At SARS-CoV-2 diagnosis, 42.5% were receiving glucocorticoids (GC), 73.9% conventional (c) disease modifying antirheumatic drugs (DMARD), 24% biologic (b) DMARD and 9.1% targeted synthetic (ts) DMARD. Among bDMARD, the most frequently used were TNF inhibitors (17%), followed by abatacept (2.8%), IL-6 inhibitors (2.4%) and rituximab (RTX) (2.1%). During the SARS-CoV-2 infection, 95.8% had symptoms, 27% required hospitalization, 7.9% presented complications and 4.4% died due to COVID-19. Severe disease and death (WHO-OS≥5) was present in 7.5% of the patients. They were older (62.9±12.5 vs 52.2±12.7, p<0.001), and they had more frequently ILD (18.5% vs 2%, p<0.001), comorbidities (82.5% vs 43.7%, p<0.001), ≥2 comorbidities (60.3% vs 25.8%, p<0.001), treatment with GC (61% vs 40.7%, p=0.04) and RTX (8.3% vs 1.6%, p=0.007). Conversely, the use of cDMARD and TNF inhibitors was more frequent in patients with WHO-OS<5, nevertheless this difference was not significant. Disease activity was comparable between groups. In multivariable analysis, older age, the presence of diabetes, ILD, the use of GC and RTX were significantly associated with WHO-OS≥5 (Figure 1). Furthermore, older age (65.7±10.8 vs 52.4±12.8, p<0.001), the presence of comorbidities (87.9% vs 44.7%, p<0.001), chronic obstructive pulmonary disease (21.9% vs 5.2%, p=0.002), diabetes (30.3% vs 7.9%, p<0.001), hypertension (57.6% vs 25.6%, p<0.001), cardiovascular disease (15.6% vs 3.2%, p=0.005), cancer (9.1% vs 1.3%, p=0.001), ILD (23.3% vs 2.4%, p<0.001) and the use of GC (61.8% vs 41.4%, p=0.02) were associated with mortality. Older age [OR 1.1 IC95% 1.06-1.13] and the use of GC 5-10 mg/day [OR 4.6 IC95% 1.8-11.6] remained significantly associated with death due to COVID-19.

Figure 1.

Factors associated with severe disease and death due to COVID-19 (WHO-OS≥5) in patients with rheumatoid arthritis. Multivariable analysis. (ref.: reference; PDN: prednisone; OR: odds ratio; CI: confidence interval)

Conclusion

Treatment with RTX and GC, as well as older age, the presence of diabetes and ILD were associated with poor COVID-19 outcomes in this national cohort of patients with RA. Older patients and those taking GC had a higher mortality rate.

References

[1]World Health Organization coronavirus disease (COVID-19) Therapeutic Trial Synopsis Draft 2020.

Disclosure of Interests

None declared

Beclomethasone/formoterol in the management of COPD: a randomised controlled trial

OBJECTIVES

To evaluate the effect of beclomethasone/formoterol versus budesonide/formoterol (non-inferiority) and versus formoterol (superiority) in patients with severe stable chronic obstructive pulmonary disease (COPD).

METHODS

A double-blind, double-dummy, randomised, active-controlled, parallel-group study. After 4 weeks run-in with ipratropium/salbutamol (40/200 μg, three times daily) patients were randomised to receive beclomethasone/formoterol (200/12 μg pressurised metered dose inhaler), budesonide/formoterol (400/12 μg dry powder inhaler) or formoterol (12 μg dry powder inhaler) twice daily for 48 weeks. Co-primary efficacy variables were change from baseline to 48 weeks in pre-dose morning forced expiratory volume in 1 s (FEV(1)) and mean rate of COPD exacerbations.

RESULTS

Of 718 patients randomised, 703 (232 beclomethasone/formoterol, 238 budesonide/formoterol, 233 formoterol) were in the ITT analysis. Improvement in pre-dose morning FEV(1) was 0.077 L, 0.080 L and 0.026 L for beclomethasone/formoterol, budesonide/formoterol and formoterol respectively (LS mean from the ANCOVA model). Beclomethasone/formoterol was not inferior to budesonide/formoterol (95% CI of the difference -0.052, 0.048) and superior to formoterol (p = 0.046). The overall rate of COPD exacerbations/patient/year was similar and not statistically significantly different among treatments (beclomethasone/formoterol 0.414, budesonide/formoterol 0.423 and formoterol 0.431). Quality of life and COPD symptoms improved in all groups and use of rescue medication decreased. Safety profiles were as expected and treatments well-tolerated.

CONCLUSIONS

Beclomethasone/formoterol (400/24 μg) treatment for 48 weeks improved pulmonary function, reduced symptoms compared to formoterol, was safe and well-tolerated in patients with severe stable COPD. Neither of the long-acting β2-agonist/inhaled corticosteroid combinations affected the low exacerbation rate seen in this population.

COPD increases the risk of squamous histological subtype in smokers who develop non-small cell lung carcinoma

BACKGROUND

Squamous cell carcinoma has a stronger association with tobacco smoking than other non-small cell lung cancers (NSCLC). A study was undertaken to determine whether chronic obstructive pulmonary disease (COPD) is a risk factor for the squamous cell carcinoma histological subtype in smokers with surgically resectable NSCLC.

METHODS

Using a case-control design, subjects with a surgically confirmed diagnosis of squamous cell carcinoma were enrolled from smokers undergoing lung resection for NSCLC in the District Hospital of Ferrara, Italy. Control subjects were smokers who underwent lung resection for NSCLC in the same hospital and had a surgically confirmed diagnosis of NSCLC of any histological type other than squamous cell.

RESULTS

Eighty six cases and 54 controls (mainly adenocarcinoma, n = 50) were enrolled. The presence of COPD was found to increase the risk for the squamous cell histological subtype by more than four times. Conversely, the presence of chronic bronchitis was found to decrease the risk for this histological subtype by more than four times. Among patients with chronic bronchitis (n = 77), those with COPD had a 3.5 times higher risk of having the squamous cell histological subtype.

CONCLUSIONS

These data suggest that, among smokers with surgically resectable NSCLC, COPD is a risk factor for the squamous cell histological subtype and chronic bronchitis, particularly when not associated with COPD, is a risk factor for the adenocarcinoma histological subtype.

Effects of nicotine replacement therapy on markers of oxidative stress in cigarette smokers enrolled in a smoking cessation program

Twenty healthy, asymptomatic long-term cigarette smokers (8 males, 12 females; mean age: 43 +/- 9 years) were selected at random from a larger series receiving nicotine replacement therapy (NRT) for 12 weeks to study the effects of NRT on plasma markers of oxidative stress. Plasma aliquots, obtained at baseline (T0) and after 12 weeks (T12) of NRT, were used to measure malondialdeyde (MDA) and total Trolox-equivalent antioxidant capacity (TEAC). In subjects who completely quit smoking ('quitters', n = 10), MDA was higher at T0 (1.08 mumol/l, interquartile range 0.85-1.16) than at T12 (0.71 mumol/l, range 0.32-0.92; p < 0.01), and TEAC was lower at T0 (1.20 mM, range 1.11-1.31) than at T12 (1.43 mM, range 1.31-1.49; p < 0.05). In subjects who had only reduced the number of cigarettes smoked per day ('reducers', n = 10), differences between the T0 and T12 levels of MDA (0.81 [0.75-0.96] vs. 0.76 [0.58-0.84] mumol/l) and TEAC (1.28 [1.05-1.50] vs. 1.25 [1.09-1.42] mM) were not significant. At T0, MDA and cotinine levels correlated in reducers (r = 0.79, p < 0.05) and, though not significantly, in quitters (r = 0.50, p = 0.12). At T12 this relationship between MDA and cotinine was still present in the reducers (r = 0.70, p < 0.05), while the scatter of points in quitters was completely dispersed (r = (0.09). These results show that smoking cessation but not smoking reduction is associated with decreased markers of oxidative stress in the plasma of active cigarette smokers.

A randomized study comparing two different schedules of administration of cisplatin in combination with gemcitabine in advanced nonsmall cell lung carcinoma

BACKGROUND

This randomized trial was designed to investigate the feasibility, toxicity, and activity of two different schedules of gemcitabine plus cisplatin in previously untreated patients with advanced (International Union Against Cancer (UICC) Stage IIIB-IV) nonsmall cell lung carcinoma (NSCLC).

METHODS

From February 1997 to September 1998, 82 patients with advanced NSCLC were entered onto the study and were randomized to gemcitabine 1000 mg/m(2) on Days 1, 8, and 15 plus cisplatin 80 mg/m(2) on Day 2 (arm A) or Day 15 (arm B) every 28 days.

RESULTS

All the patients were assessable for toxicity (arm A/arm B: 151/177 cycles; median, 4 of 5 cycles per patient), and the following Grade 3-4 toxicities were reported (percentage of cycles in arm A vs. arm B): anemia, 7.9% and 2.3% (P < 0.05); leukopenia, 6.0% and 6.7%; thrombocytopenia, 15.0% and 1.6% (P < 0.01); no World Health Organization (WHO) Grade 3-4 nonhematologic toxicities were observed. These side effects led to gemcitabine dose reductions in 35.1% of courses in arm A and 22.0% of courses in arm B (P < 0.05) and to gemcitabine omissions in 28.5% of courses in arm A versus 7.3% of courses in arm B (P < 0.01). Dose intensities (DIs) of gemcitabine were 607.5 mg/m(2)/week in arm A and 711.6 mg/m(2)/week in arm B (P < 0.01); DIs of cisplatin were 18. 1 mg/m(2)/week in arm A and 18.8 mg/m(2)/week in arm B. The total delivered doses of gemcitabine were 9315.5 mg/m(2) in arm A and 12, 631.0 mg/m(2) in arm B (P < 0.01); the total delivered doses of cisplatin were 277.1 mg/m(2) in arm A and 333.0 mg/m(2) in arm B (P < 0.01). Response rates according to intention to treat were 40.4% (95% confidence interval [CI], 25.5-55.3) in arm A and 45% (95% CI, 29.5-60.5) in arm B. The overall median duration of response was 7.4 months; the median time to disease progression was 6 months (95% CI, 3-9) in arm A and 9 months (95% CI, 4-14) in arm B (P < 0.02); the median overall survival was 10 months (95% CI, 7.0-12.5) in arm A and 17 months (95% CI, 13.0-21.6) in arm B (P < 0.01); the 1-year survival rates were 34% and 63%, respectively.

CONCLUSIONS

Our data show that arm B (cisplatin on Day 15) is less toxic than arm A (cisplatin on Day 2) and allows the administration of significantly higher total doses and dose intensities of chemotherapy. No significant differences in response rates were observed between the two schedules; patients on arm B experienced a significantly more prolonged progression free and overall survival; however, the study was not powered to detect differences in these outcomes.

Studies on the distribution of high-level gentamicin-resistant Enterococcus faecalis using ribotyping and restriction analysis of the 16S-23S rRNA intergenic spacer sequences

Twenty-five high-level gentamicin resistant (HLGR) Enterococcus faecalis strains were isolated from three different University laboratories in Italy. The resistant strains were variously distributed in the three centers with percentages of prevalence ranging from about 3% up to 14%. Almost all strains shared high-level resistance to streptomycin (23 out of 25). Ribotyping and restriction analysis of the 16S-23S rRNA intergenic spacer sequences were used to genetically differentiate the various strains and to study their spreading in the university hospitals serviced by the three laboratories. At least three ribotypes were identified, which showed a peculiar distribution in the various centers. Only the ribotype B was isolated from the University of Padua. In Cagliari, most strains belonged to ribotype A (4/6), whereas in Genoa there was an equal distribution of the ribotypes A and B. A clonal spreading of some HLGR strains is suggested by these findings. The restriction analysis of the 16S-23S rRNA intergenic-spacer sequences gave comparable results with classical ribotyping and, in addition, was quicker and easier to perform than the latter.

Gemcitabine monotherapy in elderly patients with advanced non-small cell lung cancer: a multicenter phase II study

BACKGROUND

This trial investigated the activity and toxicity of gemcitabine in previously untreated elderly (> 70 years) patients with advanced (stage IIIB-IV) non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

From January 1997 to July 1998, 46 patients with advanced NSCLC aged over 70 years with a performance status of 0-2 were entered into the study. Gemcitabine 1000 mg/m2 was administered as a 30-min infusion once a week for 3 weeks followed by a week of rest; cycles were repeated every 4 weeks.

RESULTS

Forty-four patients were evaluable for response. One complete response and nine partial responses were observed, for an overall response rate of 22.2% (95% C.I.: 11.3-37.5). The median time to disease progression was 5.1 months (95% C.I.: 3.5-6.7), the median duration of response was 6.3 months, and the median overall survival time 6.75 months (95% C.I.: 5.3-8.2). All patients were evaluable for toxicity (184 cycles, median = 3 cycles/patient) and no grade 4 hematologic toxicities were reported. WHO grade 3 leukopenia, neutropenia and anemia occurred in 3.3, 0.5 and 1.1% of cycles, respectively. Grade 3 skin rash occurred in 4.3% of patients. These side effects led to treatment discontinuation in two patients.

CONCLUSION

Our data show that gemcitabine is active and well tolerated in patients aged over 70 years with advanced NSCLC.

ICAM-1-independent adhesion of neutrophils to phorbol ester-stimulated human airway epithelial cells

Intercellular adhesion molecule-1 (ICAM-1) is the only inducible adhesion receptor for neutrophils identified in bronchial epithelial cells. We stimulated human airway epithelial cells with various agonists to evaluate whether ICAM-1-independent adhesion mechanisms could be elicited. Phorbol 12-myristate 13-acetate (PMA) stimulation of cells of the alveolar cell line A549 caused a rapid, significant increase in neutrophil adhesion from 11 +/- 3 to 49 +/- 7% (SE). A significant increase from 17 +/- 4 to 39 +/- 6% was also observed for neutrophil adhesion to PMA-stimulated human bronchial epithelial cells in primary culture. Although ICAM-1 expression was upregulated by PMA at late time points, it was not affected at 10 min when neutrophil adhesion was already clearly enhanced. Antibodies to ICAM-1 had no effect on neutrophil adhesion. In contrast, antibodies to the leukocyte integrin beta-chain CD18 totally inhibited the adhesion of neutrophils to PMA-stimulated epithelial cells. These results demonstrate that PMA stimulation of human airway epithelial cells causes an increase in neutrophil adhesion that is not dependent on ICAM-1 upregulation.

Serum antibodies to benzo(a)pyrene diol epoxide-DNA adducts in the general population: effects of air pollution, tobacco smoking, and family history of lung diseases

Polycyclic aromatic hydrocarbons (PAHs) are almost ubiquitous pollutants that may interact with metabolic systems in human tissues and eventually cause cancer. PAH-adducted DNA becomes antigenic and antibodies anti-benzo(a)pyrene diol epoxide (BPDE)-DNA may be found in serum of PAH-exposed subjects. The presence of serum antibodies anti-BPDE-DNA adduct was investigated in 1345 individuals from family clusters of the general population of a small area in central Italy in whom information about smoking habits, site of residence, and personal and family history of lung diseases, including cancer, were obtained. Anti-BPDE-DNA antibodies in the sera were detected with a direct ELISA and the association of anti-BPDE-DNA antibodies with subjects' data from a standardized respiratory questionnaire including age, occupation, tobacco smoking habits, respiratory symptoms, and family history of respiratory diseases was subsequently tested by multivariate logistic regression analysis. The overall prevalence of subjects with anti-BPDE-DNA antibodies was 21.0% (n=283), with no differences between males and females. Anti-BPDE-DNA positivity was associated with living in the urban area [odds ratio (OR), 1.49; 95% confidence interval (CI), 1.16-1.92], with active tobacco smoking (OR, 1.25; 95% CI, 1.06-1.48), and with family history of lung cancer (OR, 1.30; 95% CI, 0.90-1.88), and positivity increased with the number of members in the family cluster positive to anti-BPDE-DNA antibodies (OR, 1.30; 95% CI, 1.03-1.65). This study on a large general population sample indicates that serum anti-BPDE-DNA antibodies may be considered as biomarkers of exposure to environmental carcinogens and of DNA damage. The genetic and familial components of their association with tobacco smoking lend further support to the argument about the familial predisposition to lung cancer.

A rapid method for screening large numbers of environmental microorganisms for antiviral activity

A new method for screening microbial colonies endowed with antiviral activity is described. It is based on close contact between microbial agar cultures and agar-covered virus-infected-cell monolayers and allows the screening of large numbers of colonies in just a few months.

Plasma 3-nitrotyrosine in cigarette smokers

Peroxynitrite has been associated with increased oxidative reactions and DNA damage in inflamed tissues as it may cause a reduction of plasma antioxidants as well. Nitration of tyrosine residues of proteins leads to the production of 3-nitrotyrosine (NTYR), which may be considered as a marker of NO.-dependent oxidative damage. We developed a highly sensitive method to detect NTYR in human plasma and tested it in cigarette smokers and in healthy control subjects. Peripheral venous blood (10 ml) was obtained in 20 healthy, asymptomatic cigarette smokers (13 males, 7 females; age: 49 +/- 11 yr) and in 18 healthy nonsmokers (10 males and 8 females; age: 36 +/- 6 yr). In smokers, plasma nicotine, cotinine, and expired CO levels were measured. NTYR was determined with a sequential HPLC/gas chromatography-thermal energy analysis (GC-TEA) technique. The total plasma Trolox-equivalent antioxidant capacity (TEAC) was also measured using metmyoglobin as peroxidase and a phenothiazine as a radical donor. NTYR was detectable (detection limit: 0.02 ng/injection) in 11 smokers (mean +/- SD: 1.60 +/- 1.24 ng/mg protein) and in two nonsmokers (1.10 and 1.20 ng/mg protein, respectively). NTYR was not associated with nicotine and cotinine levels or expired CO in smokers. Plasma TEAC in smokers was significantly lower (0.43 +/- 0.38 mM) than in nonsmokers (1.42 +/- 0.3 mM; p < 0.001) and showed a biphasic, negative relationship with NTYR (r = 0.96, p < 0.001). This highly sensitive HPLC/GC-TEA method for detection and quantitation of plasma NTYR may be used for monitoring oxidative reactions associated with tobacco smoking. This assay might be incorporated into molecular epidemiologic studies for lung chronic inflammatory and neoplastic disorders in which exposure to oxidants may be an important risk factor.

Genotypic differentiation of Gardnerella vaginalis by amplified ribosomal DNA restriction analysis (ARDRA)

In total 34 strains of Gardnerella vaginalis were analyzed with various molecular techniques in order to find the possibility of dividing this single species into different genotypes. Classical ribotyping, PCR-ribotyping and restriction analysis of 16S-23S rRNA intergenic spacer sequences were all unsuccessful in genotype differentiation of these bacteria. Only amplified ribosomal DNA restriction analysis (ARDRA) was suitable in recognizing different G. vaginalis genotypes. At least 3-4 genotypes were identified with different restriction enzymes, some of which showed a prevalent distribution in certain of the centers from which they were collected. Although in this study no correlation was found between bacterial vaginosis and any of the genotypes identified, the ARDRA method could prove to be a useful tool for studying the etiopathology and epidemiology of G. vaginalis.

Presence and persistence of serum anti-benzo[a]pyrene diolepoxide-DNA adduct antibodies in smokers: effects of smoking reduction and cessation

Among biomarkers of tobacco smoke (TS)-induced genotoxic damage, benzo[a]pyrene diolepoxide-DNA adducts (BPDE-DNA) are extensively studied. Adducted DNA becomes antigenic and antibodies anti-BPDE-DNA (BPDE-DNA-Abs) may be found in serum of exposed subjects. Little is known about the persistence of BPDE-DNA, and no study has been performed to evaluate the persistence of BPDE-DNA-Abs after cessation of exposure. Fifty heavy smokers, enrolled in a smoking cessation program with nicotine patch substitution therapy, were evaluated for the presence of BPDE-DNA-Abs before (w0) and 1, 3, 6 and 12 weeks (w1-12) after the start of the program. Nicotine or placebo patches were randomly assigned to the subjects. BPDE-DNA-Abs were determined in serum by non-competitive ELISA. After the start of the cessation program, 28 subjects quit smoking (group Q) and the other 22 reduced by about 75% the number of cigarettes smoked per day (group R). At the start of the program (w0) 8% of subjects were positive. At w1 the prevalence of positivity had increased both in subjects who quit smoking (Q: 21%) and in subjects who had reduced the number of cigarettes per day (R: 27%). Positivity remained stable up to w12 (21%) for group Q, whereas it increased to 41% in group R. Serum BPDE-DNA-Abs can be detected in smokers, and their persistence for months after smoking cessation suggests their usefulness for relatively long-term surveys. The low percentage of positivity in actual heavy smokers and the increase in antibody positivity with smoking cessation or reduction must be taken into account when interpreting serum BPDE-DNA-Ab measurement in exposed individuals.

Detection of N7-methyldeoxyguanosine adducts in human pulmonary alveolar cells

Alkylating agents may cause DNA damage in different human cells and tissues, including lungs. For instance, tobacco-specific N-nitrosamines are known to produce methyl-DNA adducts, such as N7-methyldeoxyguanosine, and to induce lung tumors. We applied a combined high-performance liquid chromatography (HPLC)/32P-postlabeling technique for measurement of N7-methyldeoxyguanosine in human pulmonary alveolar cells (HPAC). Thirty patients (13 males, 17 females; mean age 51 +/- 17 yr) undergoing bronchoalveolar lavage for diagnosis of nonmalignant lung diseases were studied. DNA was extracted from HPAC, digested to 2'-deoxyribonucleotide 3'-monophosphates and HPLC separated to obtain deoxyguanosine (dGp) and N7-methyldeoxyguanosine (N7-MedGp) monophosphates. Fractions corresponding to normal (1:10,000) and N7-methylated dGp were subsequently 32P-postlabeled by T4 polynucleotide kinase with high specific activity 32P-ATP, resolved by two-dimensional thin-layer chromatography (TLC) and autoradiographed after 3 to 18 h exposure. Spots corresponding to dGp and N7-MedGp were scraped off the plates and quantitated by liquid scintillation counting to calculate direct molar ratios. Recovered HPAC (14.4 +/- 10.0 x 10(6)) were predominantly macrophages (73.8 +/- 16.4%) and lymphocytes (9.8 +/- 11.6%). N7-MedGp was detected in 11 patients, the level ranging from 0.10 to 48.03 fmol/micrograms DNA which corresponded to 0.31-79.00 x 10(-6) N7-MedGp/dGp ratios. Detection of N7-MedGp in HPAC was associated with the smoking habit of patients: N7-MedGp was present in 7 of 10 smokers, 2 of 10 ex-smokers, and 2 of 10 nonsmokers (P < 0.05). These results show that HPAC may be used for molecular dosimetry of DNA damage by alkylating agents, including tobacco-specific N-nitrosamines, in cigarette smokers and thus used for cancer risk assessment.

Karalicin, a new biologically active compound from Pseudomonas fluorescens/putida. I. Production, isolation, physico-chemical properties and structure elucidation

An original compound, named karalicin, was isolated from a fermentation broth of the Pseudomonas fluorescens/putida strain SS-3 (CCM 4430). Production, physico-chemical properties and structure elucidation are described.

Karalicin, a new biologically active compound from Pseudomonas fluorescens/putida. II. Biological properties

The biological activities of karalicin, a new product from the Pseudomonas fluorescens/putida strain SS-3 (CCM 4430) are described. It shows a weak, but specific and irreversible, antiviral activity on Herpes simplex viruses. It also presents some inhibitory activity on different species of yeasts.

A way to select on clinical grounds patients with high risk for pulmonary embolism: a retrospective analysis in a nested case-control study

We studied 196 patients with suspicion of pulmonary embolism (PE), subsequently confirmed in 98 by positive pulmonary angiography and excluded in 98 by normal or near-normal perfusion lung scan. Patients had a clinical questionnaire for history, and, soon after. a radiograph, blood gas analysis, and an ECG. Clinical and instrumental signs were matched in patients with confirmed and unconfirmed PE to find those more frequent in embolic patients and, thus, more characteristic of PE. The following were: previous PE, immobilization and thrombophlebitis (p < 0.05); dyspnea and cough (p < 0.05); enlarged descending pulmonary artery (DPA), enlarged right heart, pulmonary infarction, Westermark sign (p < 0.001), and elevated diaphragm (p < 0.05); hypoxemia. No ECG sign was more frequent in PE. Thereafter, all variables were processed separately with a logistic multiple regression analysis and those significantly associated to PE were tested in a final logistic model that was able to predict the actual result of angiography or scintigraphy; accordingly, previous PE, immobilization, thrombophlebitis, enlarged DPA, pulmonary infarction, Westermark sign, hypoxemia were significantly associated with a high risk of PE (from 2.8 to 15 times greater than in patients without these signs). Therefore, we may conclude that clinical assessment and noninvasive tests may help to detect patients at higher risk for PE where heparin coverage should be started while waiting for conclusive diagnostic procedures.

The role of suspicion in the diagnosis of pulmonary embolism

Pulmonary embolism (PE) is largely undiagnosed because clinical suspicion is not raised in most instances, and thus, patients with PE go undetected. In this paper, we try to define the role of clinical assessment (including chest radiography, electrocardiogram, arterial blood gas analysis) in making the diagnosis early, accurate, and at low cost, and propose a flow chart to be used in clinical practice. All patients with otherwise unexplained dyspnea or chest pain should be sent for perfusion lung scintigraphy; accordingly, underdetection of PE and mortality of PE should be reduced. If, within 1 h after the clinical suspicion has been raised, the above-mentioned simple and noninvasive examinations are available, they may be employed to reduce the number of unnecessary procedures, without losing patients actually affected by PE. Finally, when diagnostic tools are not promptly available, noninvasive techniques may be employed to identify patients with the highest probability of PE where to start with heparin coverage while waiting for definitive diagnosis.

Host factors in lung carcinogenesis

The interaction between aetiological factors (e.g. tobacco smoke) and target cells in lung tissues is modulated by host factors, leading to variable risk among individuals. We have studied some of the metabolic properties of the human lung and the effects on them of tobacco smoke. The activity of activating enzymes is induced by recent tobacco smoke exposure, whereas that of inactivating enzymes is depressed, and this effect is greater in patients with lung cancer than in controls. This imbalance between activating and detoxifying enzymes in the lung may be a key factor in determining the genetic damage to the lung. These differences between lung cancer patients and controls in metabolic activities in lung tissues may be documented at a phenotypic level as well as at a genotypic level. Also wide interindividual differences have been shown in deoxyribonucleic acid (DNA) repair enzymes and in the extent of DNA damage.

Antimicrobial activity of 5-substituted-3-amino-1,2,4-triazoles

Some dyes derived from 3-amino-5-(ortho, meta, and para-pyridyl)-1,2,4-triazoles were tested for antimicrobial activity. 13 compounds showed anti-staphylococcal activity and one had anti-candida activity. Some substances had antimicrobial activity only after light irradiation.

7-Alkyldeoxyguanosine adduct detection by two-step HPLC and the 32P-postlabeling assay

7-Alkyldeoxyguanosine DNA adducts may be a marker for some N-nitroso compound exposures and subsequent human cancer risk. A sensitive and highly specific assay for the detection of 7-methyl-2'-deoxyguanosine-3'-monophosphate (7-methyldGp) and 7-ethyl-2'-deoxyguanosine-3'-monophosphate (7-ethyldGp) has been developed by combining two different HPLC purification steps with the 32P-postlabeling assay. We previously reported that ion-pair reverse-phase (IP) chromatography coupled with the 32P-postlabeling assay detects 7-methyldGp in human lung, but have found that other nucleotides and unknown adducts co-elute. Thus, weak anion exchange (AE) HPLC was added in tandem with IP HPLC prior to the 32P-postlabeling assay. 2'-Deoxyguanosine-3'-monophosphate (dGp) is incorporated into the assay as an internal standard for the assessment of enzyme labeling efficiency and adduct recovery. The methodology was validated using radiolabeled DNA and liquid scintillation counting, which accounts for adduct loss from enzymatic digestion to detection. Levels of 7-ethyldGp also were correlated with accelerator mass spectrometry. The overall adduct recovery with this method was 58% for 7-methyldGp and 98% for 7-ethyldGp. The detection limit for both assays using 100 micrograms of DNA was one adduct in 10(8) unmodified dGp. 7-MethyldGp and 7-ethyldGp levels were determined in ten human lung samples at levels of 1.4-5.4 and 0.6-3.1 adducts per 10(7) dGp respectively, and in five human lymphocyte samples at levels of 5.0-8.3 and 0.3-1.4 adducts per 10(7) dGp respectively. Combining the two HPLC purification steps and the 32P-postlabeling assay attains chemical specificity, retains sufficient quantitative sensitivity and should be useful in human biomonitoring studies.

Standardization of the 32P-postlabeling assay for polycyclic aromatic hydrocarbon-DNA adducts

A modified method for the 32P-postlabeling assay that permits standardized quantitation for specific polycyclic aromatic hydrocarbon (PAH)-DNA adducts is described. This method has been designed to test the components of the 32P-postlabeling assay for use in the chemically specific detection of individual adducts with the ultimate goal of testing the biological significance of PAH-DNA adducts in humans. The approach relies upon high performance liquid chromatography (HPLC), concomitant labeling of 2'-deoxyguanosine (dGp) as an internal standard and thin layer chromatography (TLC), which identifies unmodified nucleotides along with PAH-DNA adducts on the same TLC plate. This method assesses labeling efficiency, detects the presence of unknown inhibitors, assesses the adequacy of digestion (when combined with HPLC) and allows for the development of calibration curves for directly determined molar ratios (adduct:internal standard). Chemically synthesized adduct standards and quantitative 32P-postlabeling data have been corroborated by UV spectroscopy, fluorescence spectroscopy and liquid scintillation counting where radiolabeled materials were available. Labeling efficiencies of the PAH-DNA adducts were found to be up to 100-fold less than expected and depended upon both the adduct and adduct levels (lower levels being less efficiently detected). The presence of unmodified nucleotides resulted in a 1.5-fold lower labeling efficiency. Mixtures of selected PAH-DNA adducts did not affect the labeling efficiencies of each other. The data suggest that previous 32P-postlabeling assay studies for PAH-DNA adducts may have underestimated adduct levels due to variations in labeling efficiency.

Early and late follow-up of pulmonary embolism

This study includes 61 patients referred with pulmonary embolism (PE) during 1 year. At admission, blood gas analysis, chest radiography and pulmonary lung scan were obtained in each patient; in a subset of patients pulmonary angiography was also performed to make the definitive diagnosis. Patients were treated with heparin and, later, with oral anticoagulants. Blood gas analysis, chest radiograph and perfusion lung scan were repeated 7, 30, 180 and 365 days after the diagnosis to evaluate the usefulness of these techniques in the follow-up of PE. Arterial hypoxemia and perfusion impairment recovered in parallel, both in the acute phase after embolism (7 days) and later up to 1 year. The great majority of recovery occurred within the first month after embolization. Radiographic signs compatible with PE tended to decrease early and disappeared almost completely after 30 days. Arterial blood gas analysis and perfusion scintigraphy detected 8 recurrences of PE that would be missed by chest radiograph. Arterial hypoxemia and the enlargement of descending pulmonary artery were positively correlated with the number of unperfused lung segments and, thus, may help predicting the severity of perfusion impairment in the acute stage. In conclusion, blood gas analysis and chest radiograph may be employed with or without perfusion lung scan to follow patients with PE up to 1 month after embolization; after that, only blood gas analysis and perfusion lung scan may give useful information about recovery from or recurrence of PE.

An improved fluorometric assay for dosimetry of benzo(a)pyrene diol-epoxide-DNA adducts in smokers' lung: comparisons with total bulky adducts and aryl hydrocarbon hydroxylase activity

An improved high-performance liquid chromatography/fluorometric assay has been established to quantitate the benzo(a)pyrene (BP) tetrols released after acid hydrolysis of lung DNA from lung cancer patients, so that the formation of benzo(a)pyrene diol-epoxide-DNA adducts can be measured. The r-7,c-10,t-8,t-9-tetrahydroxy-7,8,9,10-tetrahydro-BP isolated by high-performance liquid chromatography was determined by chromatography in two different solvent systems and fluorescence spectroscopy. This assay has a detection limit of 2 pg of r-7,c-10,t-8,t-9-tetrahydroxy- 7,8,9,10-tetrahydro-BP, requires 100-500 micrograms of DNA, and can measure 1 adduct/10(8) unmodified nucleotides. As this assay does not use immunoaffinity chromatography or solvent extraction, it allows a > 90% recovery of benzo(a)pyrene diol-epoxide-DNA adducts. This procedure has been tested on 13 DNA samples prepared from nontumorous lung parenchyma taken from lung cancer patients at surgery and revealed the presence of DNA adducts of the anti-benzo(a)pyrene diol-epoxide in 9 of 11 samples from smokers and in 2 of 2 ex-smokers. In only two samples from smokers the formation of adducts derived from syn-benzo(a)pyrene diol-epoxide was detected. A 15-fold variation in DNA adduct level was found in 11 of 13 DNA samples, with a range of 0.6-9.9 adducts of benzo(a)pyrene diol-epoxide/10(8) nucleotides. In samples containing both anti- and syn-benzo(a)pyrene diolepoxide-DNA adducts, the anti/syn adduct ratio is 2:1. A highly significant correlation was found between pulmonary microsomal aryl hydrocarbon hydroxylase activity and the level of benzo(a)pyrene diolepoxide-DNA adduct (r = 0.91; P < 0.001; n = 13). A crude linear correlation between the amounts of these adducts and those of bulky DNA adducts determined by 32P-postlabeling assay was observed in the same samples (r = 0.78; P < 0.02; n = 13). Thus this highly sensitive and specific procedure is suitable for measuring benzo(a)pyrene diolepoxide-DNA adducts in human tissues from environmentally exposed subjects and could be adapted to measure polycyclic aromatic hydrocarbons other than BP.

CT evaluation of chronic thromboembolic pulmonary hypertension

Eight patients with chronic thromboembolic pulmonary hypertension (CTPH) that had been demonstrated by perfusion lung scan, pulmonary arteriography, and right heart catheterization had their pulmonary circulation evaluated by CT. Eight subjects without lung pathology were also studied for comparison. High resolution CT from apex to base with 1 cm thick sections after intravenous injection of contrast medium was performed in each individual. Emboli lodged in main pulmonary arteries on arteriography were regularly shown by CT, whereas those in segmental or smaller arteries were not detected. Diameters of the main pulmonary arteries measured on CT correlated with systolic pulmonary artery pressure (p < 0.001). The ratio between diameters of segmental arteries and the corresponding bronchi (A/B ratio) on CT was > 1 in 72 of 144 examined pulmonary segments (18 segments for each patient) in patients with CTPH. The ratio was > 1 in only 10 of 144 examined segments in normal control subjects. Dilatation of bronchial arteries was present in four of eight patients with CTPH. The parenchymal density in patients with CTPH was significantly higher in the axial than in the middle or peripheral lung compartments. In conclusion, CT may help with the diagnosis of CTPH by detecting thrombi of main arteries and by showing characteristic findings; moreover, it is accurate in estimating pulmonary arterial pressure secondary to thromboembolic obstruction.

Carcinogen metabolism in human lung tissues and the effect of tobacco smoking: results from a case--control multicenter study on lung cancer patients

Cigarette smoking is the strongest risk factor for lung cancer, but genetically determined variations in the activities of pulmonary enzyme that metabolize tobacco-derived carcinogens may affect individual risk. To investigate whether these enzymes (e.g., CYP1A-related) can serve as markers for carcinogen-DNA damage, lung tissue specimens were taken during surgery from middle-aged men with either lung cancer or non-neoplastic lung disease. Phase I [aryl hydrocarbon hydroxylase (AHH), ethoxycoumarin O-deethylase (ECOD)] and phase II (epoxide hydrolase, UDP-glucuronosyltransferase, glutathione S-transferase) enzyme activities, glutathione and malondialdehyde contents were determined in lung parenchyma and/or bronchial tissues; some samples were also analyzed for DNA adducts, using 32P-postlabeling. The data were then analyzed for the following: a) differences in metabolic profiles between bronchial and parenchymal lung tissue; b) the effect of recent exposure to tobacco smoke on enzyme inducibility and benzo[a]pyrene metabolism; c) differences in enzyme inducibility between lung cancer and non-lung cancer patients; d) the effect of smoking on metabolism of mutagens in vitro; e) pulmonary DNA adduct levels and AHH activity in lung parenchyma of smokers and ex-smokers; f) lipid peroxidation products in lung tissue from lung cancer and non-lung cancer patients, as related to smoking habits and degree of airway obstruction; and g) prognostic value of AHH pulmonary activity in lung cancer patients. The results demonstrate a pronounced effect of tobacco smoke on pulmonary metabolism of xenobiotics and prooxidant state and suggest the existence of a metabolic phenotype at higher risk for tobacco-associated lung cancer.

Cigarette smoke inhibits cytosolic but not microsomal epoxide hydrolase of human lung

The effect of cigarette smoke exposure on the activity of cytosolic and microsomal epoxide hydrolase (EH) has been investigated in human lung. Patients were classified as 'recent smokers' (n = 9) or 'non-recent smokers' (n = 10) according to whether they were or were not still smoking 1 month before surgery. Cytosolic EH was measured with [3H]trans-stilbene oxide as a substrate, whereas microsomal EH was measured with [7-3H]styrene oxide as a substrate. Microsomal EH activity did not differ between recent smokers (2.51 +/- 0.93 nmol min-1 mg-1) and non-recent smokers (2.74 +/- 1.10 nmol min-1 mg-1), whereas cytosolic EH activity was significantly lower in recent smokers (6.46 +/- 1.79 pmol min-1 mg-1) than in non-recent smokers (8.41 +/- 2.09 pmol min-1 mg-1, P less than 0.05). Cytosolic EH activity was correlated with the number of days that had passed since the cessation of smoking (r = 0.58, P less than 0.05) and the effect was dose-dependent, since the enzyme activity was inversely correlated with the number of cigarettes smoked per day (r = 0.85, P less than 0.01). This suggests that recent smoking exposure inhibits the activity of cytosolic EH but not microsomal EH, and that the inhibition increases with the number of cigarettes smoked per day. The contribution of cytosolic enzymes to xenobiotic metabolism may be remarkable in extrahepatic tissues. The inhibition of cytosolic EH by tobacco smoke may reduce the inactivation of carcinogenic epoxides in human lung tissues and so may increase a person's susceptibility to lung cancer.

Carcinogen metabolism and DNA adducts in human lung tissues as affected by tobacco smoking or metabolic phenotype: a case-control study on lung cancer patients

Individual variations in activity of pulmonary enzymes that metabolize tobacco-derived carcinogens may affect an individual's cancer risk from cigarette smoking. To investigate whether some of these enzymes (e.g., cytochrome P450IA-related) can serve as markers for carcinogen-induced DNA damage accumulating in the lungs of smokers, non-tumorous lung tissue specimens were taken during surgery from middle-aged men with either lung cancer (n = 54) or non-neoplastic lung disease (n = 20). Phase I (AHH, ECDE) and phase II (EH, UDPGT, GST) enzyme activities, glutathione and malondialdehyde contents were determined in lung parenchyma and/or bronchial tissues; some samples were analyzed for DNA adducts, using 32P-postlabeling. Data analysis of subsets or the whole group of patients yielded the following results. (1) Phase I and II drug-metabolizing enzyme (AHH, EH, UDPGT, GST) activities in histologically normal surgical specimens of lung parenchyma were correlated with the respective enzyme activities in bronchial tissues of the same subject. (2) In lung parenchyma, enzyme (AHH, ECDE, EH, UDPGT) activities were significantly and positively related to each other, implying a similar regulatory control of their expression. (3) Mean activities of pulmonary enzymes (AHH, ECDE) were significantly (2- and 7-fold, respectively) higher in lung cancer patients who had smoked within 30 days before surgery (except GST, which was depressed) than in cancer-free subjects with a similar smoking history. (4) In the cancer patients, the time required for AHH, EH and UDPGT activities to return to the level found in non-smoking subjects was several weeks. (5) Bronchial tree and peripheral lung parenchyma preparations exhibited a poor efficiency in activating promutagens to bacterial mutagens in Salmonella. However, they decreased the mutagenicity of several direct-acting mutagens, an effect which was more pronounced in tissue from recent smokers. GSH concentration and GST activity were positively correlated with mutagen inactivation in the same sample. (6) In recent smokers, AHH activity in lung parenchyma was positively correlated with the level of tobacco smoke-derived DNA adducts. (7) Pulmonary AHH and EH activity had prognostic value in tobacco-related lung cancer patients. (8) An enhanced level of pro-oxidant state in the lungs was associated with recent cigarette smoking. Malondialdehyde level in lung parenchyma was associated with the degree of small airway obstruction, suggesting a common free radical-mediated pathway for both lung cancer induction and small airway obstruction.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of pulmonary DNA adduct levels, measured by 32P-postlabelling and aryl hydrocarbon hydroxylase activity in lung parenchyma of smokers and ex-smokers

In order to compare pulmonary DNA adducts and aryl hydrocarbon hydroxylase (AHH) activity, we have measured these two parameters in non-neoplastic surgical lung parenchymal samples from four ex-smokers and 19 smokers, out of 20 patients operated for lung cancer, and three for nonmalignant lung diseases. DNA adducts were determined by scintillation counting after 32P-postlabelling analysis. The microsomal fractions of the same lung specimen were assayed for AHH activity by a fluorometric method. Autoradiograms of DNA adducts found in lungs of smokers revealed two distinct diagonal radioactive zones that were absent in ex-smokers. The smokers had significantly higher levels (1.68-13.4 DNA adducts/10(8) nucleotides; mean +/- SD 5.38 +/- 3.19) than ex-smokers (0.23-2.21; 1.09 +/- 0.84). AHH activity in smokers ranged from 0.01 to 0.69 pmol/min/mg. This activity was significantly (P less than 0.05) higher in smokers (0.26 +/- 0.26) who had smoked until 1 week before surgery than in those who had stopped smoking for greater than 7 days (0.11 +/- 0.11). A positive linear correlation between DNA adduct levels and AHH activity (r = 0.69; P less than 0.001; n = 19) was found in smokers. This relationship could explain why AHH inducibility appears to be a crude marker for lung cancer risk in smokers.

[The diagnosis of pulmonary embolism: the role of noninvasive technics]

Today a large group of patients with pulmonary embolism is still undetected because this disease is not suspected. We evaluated the role of routine clinical procedures such as history, chest x-ray, electrocardiogram and blood gas analysis in the diagnosis of this disease. We studied 177 patients sent to our observation with suspicion of pulmonary embolism, which was later confirmed in 97 and excluded in 80. Prolonged immobilization, surgical procedures and deep vein thrombosis are the most frequent predisposing factors (P less than 0.05 or less) in patients with pulmonary embolism with respect to patients with unconfirmed suspicion of embolism. Among symptoms and signs, pleuritic chest pain, sudden onset of dyspnea, tachypnea, fever, enlarged jugular veins, enhanced pulmonary component of the second heart sound, pulmonary systolic murmur and basal hypophonesis were the most frequent signs (P less than 0.005 or less) in patients with embolism. Among radiographic signs "sausage" descending pulmonary artery, diaphragmatic elevation, pulmonary infarction, Westermark sign and azygos vein enlargement were more frequent (P less than 0.05 or less) in patients with embolism with respect to patients with unconfirmed suspicion of embolism. Among electrocardiographic signs, tachycardia, P-R segment displacement and negative T wave in V1-V2 were more frequent in patients with embolism with respect to patients with unconfirmed suspicion of embolism (P less than 0.05 or less). PO2, standard pO2 and pCO2 were significantly lower (P less than 0.001) in patients with embolism. After discriminant analysis of the whole data set most patients were correctly classified as embolic (90/97) and non-embolic (75/80).(ABSTRACT TRUNCATED AT 250 WORDS)

Does the patient's posture affect the detection of chest radiographic findings suggestive of pulmonary embolism?

Although it is accepted that thoracic structures are enlarged in supine chest radiographs, it is not known whether the lying posture may also influence the radiographic detection of abnormalities, such as those suggestive for pulmonary embolism (PE). For this purpose, we performed planar chest radiographs both in the seated and supine positions, keeping the target-to-film distance at 2 m, in 20 patients with acute PE. Chest radiograph was then repeated 1 month later in either position with the radiological conditions unchanged to investigate the effect of posture on the detection of resolution of signs. The detection of signs due to modifications of preexisting thoracic structures (elevation of the diaphragm and enlargement of the heart, right descending pulmonary artery and azygos vein) in acute PE was different between films taken in the supine and seated positions: both hemidiaphragms were more elevated (p less than 0.001), heart and central vessels were wider (p less than 0.05 or less) when patients were supine. On the contrary, the detection of signs of new occurrences ('sausage'-like appearance of the descending pulmonary artery, linear atelectasis, densities compatible with pulmonary infarction, pleural effusion and focal hyperlucency) was not influenced by the patient's position. During recovery, both kinds of abnormalities were reduced concomitantly in seated and supine radiographs. In conclusion, in acute PE, chest radiographs should be obtained in the seated position since the supine posture may overestimate signs due to modifications of preexisting thoracic structures even though it does not influence the detection of signs of new occurrences. On the contrary, films taken in either position are useful to follow the evolution of PE, provided the film is obtained in the same position and with the same technique as in the acute phase.

Reversibility of complete unperfusion in a patient with recurrent hemoptysis

We present a case of a 68-year-old woman with a history of mild smoking and chronic bronchitis who showed recurrent hemoptysis. She presented with a nearly normal chest roentgenogram, a non-diagnostic fiberoptic bronchoscopy and a computed tomography and lung scanning both of which were highly suggestive for malignancy. In fact, the former showed obstruction of the main left bronchus, of the superior bronchus for the left upper lobe and of the apical bronchus for the left lower lobe, the latter showed a total cessation of blood flow through the left lung. Pulmonary angiography, however, was normal and aortography showed dilatated and twisted left bronchial arteries. Computed tomography and lung scanning came back to normal after bronchoscopic aspiration of endobronchial clots and a nonspecific antibiotic therapy were carried out. Although very infrequent, bronchial stenosis on CT and complete monolateral unperfusion on lung scintigraphy may occur in patients with hemoptysis of benign origin. We recommend the use of pulmonary arteriography in patients with the above pattern when diagnostic doubt remains after bronchoscopy.

Pulmonary lipid peroxidation in cigarette smokers and lung cancer patients

Lipid peroxidation (LPO) was studied in lung tissues of patients with lung cancer (LC, n = 37) or nonlung cancer (NLC, n = 13) and its relationships with the smoking habits and the degree of airway obstruction were investigated. Specimens of peripheral lung parenchyma, free of tumor tissue, were taken and the malondialdehyde (MDA) content was measured in the S-12 fractions. Airway obstruction was assessed by flow-volume curves, and data were expressed as percentage of the predicted values. Cigarettes smoked were expressed as pack-years. The patients with LC and NLC did not differ by MDA content, age, and number of pack-years. On the contrary, FEF75-85 and MEF75 were significantly lower in LC than in NLC patients (p less than 0.05). The MDA content was inversely correlated to number of days patients had refrained from smoking (r = -0.66, p less than 0.001). The MDA content was higher in recent smokers (ie, people smoking during the last 30 days before surgery) than in the other patients (0.136 +/- 0.007 vs 0.116 +/- 0.007 mumol/g of tissue, p less than 0.05) and, by considering only recent smokers, MDA content was higher in LC patients (0.144 +/- 0.008 mumol/g of tissue) than in NLC patients (0.113 +/- 0.014 mmol/g tissue, p = 0.059). When patients were divided into "high MDA" and "low MDA" groups, MEF75 was much lower in the high MDA group (35.1 +/- 3.4 percent) than in the low MDA group (55.1 +/- 8.1 percent) (p less than 0.01). These results suggest the following: (1) enhanced level of prooxidant state in the lungs is associated with recent cigarette smoking; (2) LC patients may be more prone than respective NLC patients to oxidative stress; (3) MDA level and degree of small airway obstruction were associated and differed between LC and NLC patients even though these groups did not differ in the percentage of recent smokers; and (4) a common free-radical mediated pathway may be active for both LC and small airway obstruction.

Possible prognostic value of pulmonary AH-locus-linked enzymes in patients with tobacco-related lung cancer

As prognosis in breast cancer patients has been related to the AHH activity in their breast tissue, we have conducted a similar analysis on pulmonary drug metabolizing enzymes as prognostic markers for male lung cancer patients, primarily investigated for other reasons. A subset of 50 patients with lung cancer related to tobacco use, who had undergone thoracic surgery, was re-analyzed. The activity of parenchymal aryl hydrocarbon hydroxylase (AHH) and epoxide hydrolase (EH) that had been determined previously in homogenates of non-neoplastic surgical lung specimens, was used for comparisons of the patients' survival after surgery. When the crude mortality percentages at 1 and 2 years by AHH or EH activity, subdivided into quarters of the distribution, were calculated, a lower mortality was related to lower enzyme levels. Subjects in the 1st and 4th quarters of the distribution showed significant differences in their 1-year survival for AHH (p = 0.05) and EH (p less than 0.01) activities. This relationship could not be accounted for by age, cumulative lifetime smoking, recent or continuing smoking, stage or histological type of disease. Thus, the levels of pulmonary AHH and EH may have some prognostic significance in tobacco-related lung cancer.

Natural course of treated pulmonary embolism. Evaluation by perfusion lung scintigraphy, gas exchange, and chest roentgenogram

Perfusion lung scintigrams, pulmonary gas exchange data, and chest roentgenograms were obtained in 33 patients during acute embolism and over the following six months in order to assess their clinical usefulness in monitoring the effect of therapy. To this purpose, the measurement of pulmonary gas exchange and the presence of chest x-ray findings were compared with perfusion lung scintigraphic abnormalities both at diagnosis and after 7, 30, and 180 days during treatment. More than 50 percent of the pulmonary arterial tree was obstructed at diagnosis, and a large part of perfusion recovery was complete within the first month. All of the gas exchange parameters were abnormal at diagnosis, and the rate of their improvement was related to that of perfusion recovery. Interestingly, PaO2st (ie, PaO2 corrected for hyperventilation) and VE tended to return to normal during the first month as a consequence of the progressive recovery of perfusion, whereas oxygen and carbon dioxide gradients and physiologic dead space showed the persistence of some abnormalities six months after diagnosis. Significant correlations were observed between the number of ULSs evaluated on the perfusion lung scintigram (and considered an index of the severity of pulmonary embolization) and all of the gas exchange parameters at diagnosis (correlation coefficients averaged from 0.41 to 0.73) and after 7 and 30 days. The enlargement of the right descending pulmonary artery and particularly the "sausage" sign and the Westermark sign were significantly associated with a higher degree of gas exchange impairment and with a more severe embolization. In conclusion, this study demonstrates that perfusion lung scintigraphy has a primary role in monitoring the recovery of patients with pulmonary embolism under treatment. Moreover, the chest roentgenogram may help in this purpose. A second major result is that the simple measurement of some gas exchange parameters may allow the assessment of functional recovery of these patients, thus giving additional information about the effect of therapy.

Improvement of screening for pulmonary embolism with a standardized questionnaire

The anamnesis is believed to be poor in identifying patients with pulmonary embolism (PE), but the method of data collection may be critical for inference on this issue. We compared the prevalences of history findings recorded after a free verbal interview (VI) by the referring physicians with those recorded after completion of a standardized questionnaire (SQ) by the admitting physicians in a group of 177 consecutive patients referred to our Emergency Unit with the suspicion of PE (subsequently confirmed in 97). VI data were incomplete in 18 patients. In the remaining 159 patients, prevalences of symptoms and predisposing factors were higher after SQ than after VI. Accordingly, 8 items (obesity, prolonged immobilization, surgery, varicose leg veins, deep venous thrombosis, pleuritic chest pain, and sudden-onset dyspnea) were significantly more prevalent in patients with confirmed PE after SQ, compared to only 2 items (prolonged immobilization and pleuritic chest pain) after VI. When we tested for the agreement between the two methods of data collection, kappa values ranged from high values (for surgery and hemoptysis) to very low values (for prolonged immobilization and recurrent phlebitis). These results show that the use of an SQ could improve the accuracy of collecting clinical data in patients with suspected PE, as they are also consistent in separating patients with PE from those with unconfirmed suspicion of PE. Moreover, it allows the clinician to be alert towards findings which could be missed when not carefully searched for and which may be useful to raise or strengthen the suspicion of this disease.

Carcinogen metabolism studies in human bronchial and lung parenchymal tissues

The pulmonary metabolism of xenobiotics was investigated by measuring the glutathione content and the activity of the aryl hydrocarbon hydroxylase, epoxide hydrolase, glutathione S-transferase, and uridine 5' -diphosphoglucuronosyl transferase enzymes in S-12 fractions of bronchial tree and peripheral lung parenchyma obtained at surgery from 21 patients. In parallel, the same preparations were used to assess either the activation of promutagens, i.e., benzo(a)pyrene, 2-aminofluorene, cyclophosphamide, and a cigarette smoke condensate, to metabolites reverting his- Salmonella typhymurium strains, or the decrease of direct-acting mutagens, i.e., sodium dichromate, 4-nitroquinoline N-oxide, epichlorohydrin, and ICR 191. As compared to bronchus preparations, parenchymal preparations contained considerably higher concentrations of reduced glutathione, had a significantly higher epoxide hydrolase activity, and, as assessed by means of a quantitative index, were more efficient in activating 2-aminofluorene and in reducing the mutagenicity of dichromate and 4-nitroquinoline N-oxide. These data may suggest that parenchymal lung tissue is more capable than bronchial tissue to detoxify reactive intermediates of xenobiotics, possibly explaining the greater susceptibility of bronchi to cigarette smoke-induced cancers.