Apoptosis induction and cell cycle perturbation in established cell lines by peroxysomicine A1 (T-514)

Peroxysomicine A1, a novel potential anticancer compound induced cell death in established cell lines and in a primary culture of rat neonatal cardiomyocytes. Non-transformed cells are less sensitive to the compound than transformed cell lines. Fluorescent microscopy of dying cells stained with DNA-specific dyes revealed chromatin condensation and nuclear fragmentation as well as membrane blebbing characteristic of apoptosis. Flow cytometry of cells treated with peroxysomicine A1, demonstrated appearance of cells containing less than 2C DNA, that indicated degradation of nuclear DNA, another hallmark of apoptotic cell death. Z-VAD, a nonspecific caspase inhibitor, prevented DNA fragmentation but not cell death registered by permeabilization of cell outer membrane. Peroxysomicine A1 also inhibited proliferation of various cell lines. Flow cytometry analysis showed significant accumulation of dividing cells in G2/M phases of cell cycle indicating, most likely delay in G2. These results provide initial insight into the mechanisms of action of peroxysomicine A1 and suggest that peroxysomicine A1 is a potent inhibitor of cell proliferation and inducer of apoptosis and may be a useful antineoplastic chemotherapeutic agent.

Short-term and long-term outcomes after bilateral lung volume reduction surgery : prediction by quantitative CT

OBJECTIVES

To evaluate selection criteria and duration of benefit for patients undergoing lung volume reduction surgery (LVRS).

METHODS

Eighty-nine consecutive patients with severe emphysema who underwent bilateral LVRS were prospectively followed up for up to 3 years. Patients underwent preoperative pulmonary function testing, 6-min walk, chest CT, and answered a baseline dyspnea questionnaire. CT scans in 65 patients were analyzed for emphysema extent and distribution using the percentage of emphysema in the lung, percentage of normal lower lung, and the CT emphysema ratio (CTR, an index of the craniocaudal distribution of emphysema). All patients underwent at least 6 weeks of pulmonary rehabilitation prior to surgery. Outcome measures were FEV(1), 6-min walk distance, and transitional dyspnea index (TDI).

RESULTS

Compared to baseline, FEV(1) was significantly increased at 3, 6, 12, 18, 24, and 36 months after surgery (p < or = 0.008). The 6-min walk distance increased from 871 feet (baseline) to 1,110 feet (3 months), 1,214 feet (6 months), 1,326 feet (12 months), 1,342 feet (18 months), 1,371 feet (24 months), and 1,390 feet (36 months) after surgery. Despite a decline in FEV(1) over time, 6-min walk distance was preserved. Dyspnea as measured by TDI improved at 3, 6, 12, 18, 24, and 36 months after surgery. A high CTR was the best predictor of a 12% increase over baseline and an absolute increase of 200 mL in FEV(1), although with a low area under the receiver operating characteristic curve. In addition, the sensitivity and negative predictive value of the CTR were limited. No radiographic or physiologic predictor was able to consistently predict a successful increase in walk distance or TDI.

CONCLUSION

LVRS improves pulmonary function, decreases dyspnea, and enhances exercise capacity in many patients with severe emphysema, although improvement wanes 36 months after surgery.

Diaphragmatic shape change after lung volume reduction surgery

Diaphragmatic shape in normal patients was significantly different from shape in emphysema patients. Postoperative diaphragmatic shape in patients with good clinical outcome differed from preoperative shape and was similar to shape in normal patients. In patients with poor clinical outcome, surgery appeared to have little effect on diaphragm shape.

Oxygen desaturation on the six-minute walk test and mortality in untreated primary pulmonary hypertension

There are no reliable predictors of mortality in primary pulmonary hypertension (PPH). This study assessed whether exercise oxygen desaturation and distance achieved during a six-minute walk are associated with mortality in moderately symptomatic patients with PPH. Thirty-four patients with PPH underwent a pretreatment six-minute walk test, and an invasive haemodynamic assessment of pulmonary vasodilator reserve, to select the best treatment option (epoprostenol in 27 and nifedipine in 7). Median follow-up was 26 months (12 months for the nonsurvivors was 26%), and median survival, >46 months by Kaplan-Maier estimate. The mean+/-SD distance walked was 275+/-155 m and reduction in arterial oxygen saturation (Sa,O2) at maximal distance (deltaSa,O2) was 8.4+/-4.5%). A distance < or =300 m increased mortality risk by 2.4, and a deltaSa,O2 of > or = 10% increased mortality risk by 2.9. Only Sa,O2 at peak distance, deltaSa,O2 and pulmonary vascular resistance (PVR) were related to mortality. After adjusting for PVR, there remained a 27% increase in risk of death for each per cent decrease in Sa,O2. The six-minute walk distance and exercise oxygen saturation may be helpful in selecting patients with primary pulmonary hypertension for whom transplant listing is appropriate.

Acute exacerbation of chronic bronchitis: disease-specific issues that influence the cost-effectiveness of antimicrobial therapy

BACKGROUND

Acute exacerbation of chronic bronchitis (AECB) is a common condition, with substantial associated costs and morbidity. Research efforts have focused on innovations that will reduce the morbidity associated with AECB. Health care payers increasingly expect that the results of evidence-based economic evaluations will guide practitioners in their choice of cost-effective interventions.

OBJECTIVES

To provide a framework on which to base effective and efficient antimicrobial therapy for AECB, we present a concise clinical review of AECB, followed by an assessment of the available data on the economic impact of this disease. We then address several AECB-specific issues that must be considered in cost-effectiveness analyses of AECB antimicrobial interventions.

METHODS

Published literature on the clinical and economic impact of AECB was identified using MEDLINE, pre-MEDLINE, HealthSTAR, CINAHL, Current Contents/All Editions, EMBASE, and International Pharmaceutical Abstracts databases. Other potential sources were identified by searching for references in retrieved articles, review articles, consensus statements, and articles written by selected authorities.

RESULTS

In evaluating cost-effectiveness analyses of AECB antimicrobial therapy it is critical to (1) use the disease-free interval as an outcome measure, (2) evaluate the sequence of multiple therapies, (3) address the impact of both current and future antibiotic resistance, and (4) measure all appropriate AECB-associated costs, both direct and indirect.

CONCLUSIONS

Incorporating these approaches in economic analyses of AECB antimicrobial therapy can help health care organizations make evidence-based decisions regarding the cost-effective management of AECB.

Steroids in idiopathic pulmonary fibrosis: a prospective assessment of adverse reactions, response to therapy, and survival

PURPOSE

We evaluated the risk and potential benefit of high-dose corticosteroid therapy in patients with idiopathic pulmonary fibrosis.

SUBJECTS AND METHODS

We prospectively studied 41 patients with previously untreated, biopsy-proven idiopathic pulmonary fibrosis. Before treatment, we calculated clinical, radiographic, and physiologic severity-of-illness scores for each patient. We scored high-resolution computerized tomographic (CT) scans for ground glass and interstitial opacity. We determined the extent of cellular infiltration, interstitial fibrosis, desquamation, and granulation in open lung biopsy samples. Patients were monitored monthly for steroid-related side effects, response to therapy at 3 months, and mortality.

RESULTS

All patients experienced at least one steroid-induced side effect. Eleven (27%) patients were nonresponders, 11 (27%) were responders, and 19 (46%) remained stable. Of the 19 patients who died during a mean (+/- SD) follow-up of 3.3 +/- 2.3 years, 8 (42%) lost weight during the initial 3 months of steroid therapy; only 3 (14%) of the 22 patients still living (P = 0.08) experienced weight loss. In a multivariate analysis, greater fibrosis (hazard ratio [HR] = 1.4 per unit increase; 95% confidence interval [CI]: 1.0 to 1.9; P = 0.03) and cellularity (RR = 1.9 per unit increase; 95% CI: 1.3 to 2.8; 3, P <0.001) in the biopsy sample and whether a patient was classified as a responder (RR = 0.4 versus nonresponder; 95% CI: 0.2 to 1.0; P = 0.05) or stable (RR = 0.2 versus nonresponder; 95% CI: 0.1 to 0.6, P <0.001) after steroid therapy were associated with mortality.

CONCLUSION

Corticosteroid treatment for idiopathic pulmonary fibrosis is associated with substantial morbidity. Patients who remain stable or respond to corticosteroid therapy have better survival than those who fail to respond. Whether this difference reflects an effect of treatment or less severe disease can be determined only in a randomized trial.

The spectrum of acute bronchitis. Using baseline factors to guide empirical therapy

The optimal therapy for acute bronchitis depends on the causative pathogen and the presence or absence of underlying lung disease. Because there is no fast, reliable way to identify the pathogen, physicians have to rely on clinical judgment and epidemiologic characteristics. In this article, Drs Flaherty, Saint, Fendrick, and Martinez discuss how an evidence-based approach to treatment may help ensure that efficacious therapy is available in the future.

Diagnosing interstitial lung disease: a practical approach to a difficult problem

Interstitial lung disease has a variety of causes: environmental, infectious, autoimmune, and drug-related. Accurate diagnosis is essential because the prognosis and treatment of the disease varies widely depending on the cause. However, the respiratory symptoms and pulmonary radiographic picture of these various causes of interstitial lung disease are often similar, making the diagnosis of its cause confusing and frustrating. The practical, algorithmic approach to diagnosis outlined here identifies key diagnostic clues in the patient's history, physical exam, and radiographic findings.

DNA topoisomerase II inhibition by peroxisomicine A(1) and its radical metabolite induces apoptotic cell death of HL-60 and HL-60/MX2 human leukemia cells

Peroxisomicine A(1) (T-514) is a dimeric anthracenone first isolated from the plant Karwinskia humboldtiana. The compound presents a high and selective toxicity toward liver and skin cell cultures and is currently the subject of preclinical studies as an antitumor drug. To date, the molecular basis for its diverse biological effects remains poorly understood. To elucidate its mechanism of action, we studied its interaction with DNA and its effects on human DNA topoisomerases. Practically no interaction with DNA was detected. Peroxisomicine was found to inhibit topoisomerase II but not topoisomerase I. DNA relaxation and decatenation assays indicated that the drug interferes with the catalytic activity of topoisomerase II but does not stimulate DNA cleavage, in contrast to conventional topoisomerase poisons such as etoposide. Two human leukemia cell lines sensitive or resistant to mitoxantrone were used to assess the cytotoxicity of the toxin and its effect on the cell cycle. In both cases, peroxisomicine treatment was associated with a loss of cells from every phase of the cell cycle and was accompanied by a large increase in the sub-G1 region which is characteristic of apoptotic cells. The cell cycle changes were more pronounced with the sensitive HL-60 cells than with the resistant HL-60/MX2 cells (with reduced topoisomerase II activity), in agreement with the cytotoxicity measurements. Treatment of HL-60 cells with T-514 stimulated the cleavage of the poly(ADP-ribose) polymerase by intracellular proteases such as caspase-3. The cytometry and Western blot analyses reveal that peroxisomicine induces apoptosis in leukemia cells. In addition, we characterized a catabolite of peroxisomicine, named T-510R, in the form of a highly stable radical metabolite. The electron spin resonance and mass spectrometry data are consistent with the formation of an anionic semiquinonic radical. The oxidized product T-510R inhibits topoisomerase II with a reduced efficiency compared to the parent toxin and was found to be about 3-4 times less toxic to both the sensitive and resistant leukemia cell lines than T-514. Collectively, the results suggest that topoisomerase II inhibition plays a role in the cytotoxicity of the plant toxin peroxisomicine. Inhibition of topoisomerase II may serve as an inducing signal triggering the apoptotic cell death of leukemia cells exposed to the toxin. The dihydroxyanthracenone unit may represent a useful chemotype for the preparation of topoisomerase II-targeted anticancer agents.

Spectrum of Aspergillus infection in lung transplant recipients: case series and review of the literature

STUDY OBJECTIVES

(1) To define the incidence and natural history of Aspergillus colonization and infection in lung transplant recipients, and (2) to assess the impact of prophylaxis, surveillance, and therapy on the incidence and outcome of the disease.

DESIGN

Retrospective review of 133 consecutive single or bilateral lung transplantations performed at a single institution, and review of the published literature.

RESULTS

Airway colonization, isolated tracheobronchitis, and invasive pneumonia due to Aspergillus species occurred in 29%, 5%, and 8% of our series, and in 26%, 4%, and 5% of the pooled published data (all series, including ours), respectively. Greater than 50% of all diagnoses were made in the first 6 months after transplantation in both our series and the published literature. Incidence of progression from airway colonization to invasive disease was 1 in 38 in our series and 3 of 97 (3%) in the pooled published data. In patients with isolated tracheobronchitis, all 6 patients in our series and 41 of 50 patients (82%) in all published series, including ours, responded to antifungal therapy and/or surgical debridement. Among patients with invasive pneumonia or disseminated disease, however, 5 of 10 patients in our series and 26 of 64 patients (41%) in the pooled series survived their infection.

CONCLUSIONS

The role of antifungal therapy in Aspergillus airway colonization in lung transplant recipients is unclear. Data support a strategy of scheduled screening bronchoscopy followed by aggressive treatment for isolated Aspergillus tracheobronchitis in lung transplant recipients.

Timing of Lung Transplantation for Patients with Fibrotic Lung Diseases

Idiopathic pulmonary fibrosis (IPF) is typically a fatal disease that fails to respond to medical therapy. For these patients lung transplantation offers the promise of improved quality and duration of life. The initial reports of successful transplantation for IPF date back to the mid-1980s although recent data suggest IPF patients make up nearly 20% of all single lung transplants. The survival rates following lung transplantation for IPF are estimated at 67% for 1 year, 52% for 3 years, and 35% for 5 years. Mortality rates following lung transplantation for IPF are higher than emphysema, but are generally comparable to primary pulmonary hypertension. Given the relatively high mortality following transplant the decision of when to transplant a patient is of paramount importance. Although individual patients differ, generalizations predicting a poor prognosis include the diagnosis of usual interstitial pneumonia (UIP), a forced vital capacity or total lung capacity of less than 65% predicted, a diffusion capacity for carbon monoxide (DL(CO)) less than 45% of predicted, and the presence of extensive honeycombing on high-resolution computed tomographic scans. The presence of any of these features should prompt the patient and physician to consider lung transplantation as a potential therapeutic modality. Patients with interstitial lung disease related to collagen vascular diseases or other causes need to be considered on an individual basis; their prognosis is usually better than patients with IPF, and the potential for systemic involvement may preclude listing for lung transplantation.

Lung volume reduction surgery for emphysema

Over the past decades, extensive literature has been published regarding surgical therapies for advanced COPD. Lung-volume reduction surgery would be an option for a significantly larger number of patients than classic bullectomy or lung transplantation. Unfortunately, the initial enthusiasm has been tempered by major questions regarding the optimal surgical approach, safety, firm selection criteria, and confirmation of long-term benefits. In fact, the long-term follow-up reported in patients undergoing classical bullectomy should serve to caution against unbridled enthusiasm for the indiscriminate application of LVRS. Those with the worst long-term outcome despite favourable short-term improvements after bullectomy have consistently been those with the lowest pulmonary function and significant emphysema in the remaining lung who appear remarkably similar to those being evaluated for LVRS. With this in mind, the National Heart, Lung and Blood Institute partnered with the Health Care Finance Administration to establish a multicenter, prospective, randomized study of intensive medical management, including pulmonary rehabilitation versus the same plus bilateral (by MS or VATS), known as the National Emphysema Treatment Trial. The primary objectives are to determine whether LVRS improves survival and exercise capacity. The secondary objectives will examine effects on pulmonary function and HRQL, compare surgical techniques, examine selection criteria for optimal response, identify criteria to determine those who are at prohibitive surgical risk, and examine long-term cost effectiveness. It is hoped that data collected from this novel, multicenter collaboration will place the role of LVRS in a clearer perspective for the physician caring for patients with advanced emphysema.

The role of pulmonary function testing in pulmonary fibrosis

Interstitial lung diseases are characterized by disruption of the distal pulmonary parenchyma. The clinical history manifestations, cough and dyspnea, and physical exam manifestations, inspiratory crackles, are nonspecific. Pulmonary function testing aids in the evaluation and management of patients with interstitial lung disease although the pattern of abnormality is nonspecific. Pulmonary function testing can provide an estimate of histologic severity but not a definitive quantification of histologic fibrosis or inflammation. Pulmonary function tests can provide a baseline estimation of prognosis and be used to monitor disease progression or response to therapy. The forced vital capacity and diffusion capacity are the most valuable serial measurements, but further data are required to examine composite scoring and exercise gas exchange.

Cyclophosphamide in the treatment of idiopathic pulmonary fibrosis: a prospective study in patients who failed to respond to corticosteroids

STUDY OBJECTIVES

To prospectively examine the role of cyclophosphamide in patients with idiopathic pulmonary fibrosis that is unresponsive to or intolerant of high-dose steroid treatment.

DESIGN

Prospective study.

SETTING

Tertiary referral center.

PATIENTS

Nineteen patients with biopsy specimen-proven usual interstitial pneumonia who failed to respond (n = 16) or experienced adverse effects (n = 3) from corticosteroid treatment (1 mg/kg/d for 3 months).

INTERVENTION

Steroid therapy was tapered quickly, and oral cyclophosphamide, 2 mg/kg/d, was prescribed (mean duration of treatment, 6.0 +/- 0.9 months).

MEASUREMENTS AND RESULTS

In 10 patients, response to therapy was determined by pretreatment and posttreatment clinical (dyspnea), radiographic (chest radiograph), and physiologic (pulmonary function, including exercise saturation) scores (CRP). Response was defined as a > 10-point drop in CRP; stable as +/- 10-point change in CRP; and nonresponders as > 10-point rise in CRP. In nine patients, physiologic criteria were used to assess response; significant changes in pulmonary function were defined as follows: total lung capacity, +/- 10% of baseline value; FVC, +/- 10% of baseline value, diffusion capacity of the lung for carbon monoxide, +/- 20% of baseline value; and resting pulse oximetry, +/- 4% of baseline value. Patients who died while receiving or shortly after discontinuing cyclophosphamide were classified as nonresponders (n = 2). Among 19 patients treated with cyclophosphamide, only 1 patient demonstrated sustained response; 7 patients remained stable and 11 deteriorated while receiving the drug. Toxicity associated with cyclophosphamide was substantial; more than two thirds of the patients developed drug-related adverse effects, and almost half discontinued the drug prematurely due to side effects. In the remaining patients, cyclophosphamide therapy was discontinued due to lack of improvement or progressive deterioration.

CONCLUSIONS

Cyclophosphamide therapy is of limited efficacy in patients with idiopathic pulmonary fibrosis who fail to respond or who experience adverse effects from corticosteroid treatment, and adverse effects often complicate its use.

Differential diagnosis of chronic airflow obstruction

Chronic obstructive pulmonary disease is a syndrome including illnesses such as asthma, chronic bronchitis, and emphysema. Although these diseases share a common obstructive component, their optimal treatment and prognosis differ. This article examines the salient features of the history, physical exam, pulmonary function tests, and radiological evaluation which may allow the clinician to differentiate the various diseases that make up COPD; thus allowing the clinician to better target the multiple therapeutic modalities available.

Tuberculous pneumonia complicating lung transplantation: case report and review of the literature

Although tuberculosis is more common in transplant recipients than in the general population, most centres report that mycobacterial infection is very rare in comparison with the extreme variety of transplant-associated infections. Only 18 previous cases of tuberculosis-complicated lung or heart-lung transplants have been published. An unusual case is reported of Mycobacterium tuberculosis infection in a double-lung recipient who presented a radiographic feature of segmental pneumonia, mimicking a bacterial infection. Bronchoalveolar lavage revealed lymphocytosis (> 30% of isolated cells). Data regarding optimal treatment for tuberculosis in lung transplant recipients are limited. Nevertheless, therapy should not be different from that in other immunocompromised patients and should include an aggressive initial four-drug regimen (until the sputum cultures become negative) or a 6-month conventional therapy with two agents to which the organism is susceptible. Close follow-up is required to confirm the bacteriological response and minimize the likelihood of relapse. In this patient, treatment with a four-drug antituberculous regimen for 3 months followed by isoniazide and rifampicin for an additional 9 months was curative.

Weight gain after lung volume reduction surgery is not correlated with improvement in pulmonary mechanics

STUDY OBJECTIVES

Malnutrition and low body weight are common in patients with emphysema. Previous work has demonstrated correlation between severity of airflow obstruction and body weight. Lung volume reduction surgery (LVRS) is a recent advance in the treatment of patients with severe emphysema that results in improved pulmonary function. We formed the hypothesis that improved lung mechanics after LVRS would result in body weight gain.

DESIGN

Retrospective chart review.

PATIENTS

All patients who underwent bilateral LVRS for severe emphysema at the University of Michigan between January 1995 and April 1996 were eligible for the study.

MEASUREMENTS AND RESULTS

Pulmonary function and body weight were measured preoperatively and at 3, 6, and 12 months postoperatively for patients who underwent bilateral LVRS between January 1995 and April 1996. The average weight gain in 38 patients returning for 12 months of follow-up was 3.8 +/- 0.9 kg, or 6.2% of the preoperative weight. Women gained significantly more weight than men (9.2 vs 2.2%, respectively) at 1 year. Interestingly, there was no correlation between change in weight and postoperative change in FEV(1), FVC, residual volume (RV), total lung capacity (TLC), or RV/TLC at 12 months. However, there was a statistically significant correlation between weight gained and improvement in diffusion of carbon monoxide measured 12 months postoperatively.

CONCLUSIONS

This study shows that patients with severe emphysema gain weight after LVRS. These changes were independent of changes in pulmonary mechanics but may be a result of improved gas exchange. These findings provide further information about benefits of LVRS in patients with advance emphysema that are beyond simple changes in pulmonary function.

Dobutamine stress echocardiography for the preoperative evaluation of patients undergoing lung volume reduction surgery

BACKGROUND

Lung volume reduction surgery has been proposed as a bridge to lung transplantation and as definitive therapy for advanced chronic obstructive lung disease. However, patient selection criteria and optimal preoperative assessment have not been clearly defined.

OBJECTIVE

We investigated the feasibility, safety, and value of dobutamine stress echocardiography as a predictor of major early cardiac events in patients who underwent lung volume reduction surgery.

METHODS

The study population consisted of 46 patients (21 men and 25 women, mean age 59 +/- 9 years) who underwent dobutamine stress echocardiography (maximum dose 40 microg. kg(-1). min(-1) plus atropine if needed) 180 days or less before lung volume reduction surgery. Adverse cardiac events were prospectively defined and tabulated during hospitalization after the operation and at subsequent outpatient visits.

RESULTS

Dobutamine stress echocardiography was interpretable in 45 of 46 (98%) patients. There were no adverse events during testing. The studies revealed normal left ventricular systolic function at rest in all patients and normal right ventricular function in all patients but one. Thirteen patients had right ventricular enlargement. Estimated right ventricular systolic pressure was mildly elevated (>40 mm Hg) in 5 patients. Four patients (9%) had stress tests positive for ischemia. There were no perioperative deaths. Follow-up was available for 44 of 45 patients at a duration of 20.0 +/- 7.0 months. Two major adverse cardiac events occurred in the same patient in whom the results of dobutamine stress echocardiography were positive for ischemia (positive predictive value 25%, 95% confidence interval 0% to 83%; negative predictive value 100%, 95% confidence interval 90 to 100%).

CONCLUSION

Despite end-stage chronic obstructive lung disease and poor ultrasound windows, dobutamine stress echocardiography is feasible and safe in patients undergoing evaluation for lung volume reduction surgery. It yields important information on right and left ventricular function and has an excellent negative predictive value for early and late adverse cardiac events.

Respiratory response during arm elevation in isolated diaphragm weakness

Upper extremity exercise is associated with a significant metabolic and ventilatory cost that is particularly evident in patients with severe chronic airflow obstruction. In these patients abnormal ventilatory muscle recruitment has been hypothesized to relate to impaired diaphragm function resulting from hyperinflation. Similar data have never been reported in patients with isolated diaphragm weakness but without airflow obstruction or hyperinflation, a group that would ideally define the role of diaphragm function during arm elevation (AE). We prospectively studied 15 patients with isolated diaphragm weakness of varying severity (Pdi(sniff), 31.74 +/- 3.75 cm H(2)O) as contrasted with eight normal subjects (Pdi(sniff), 111. 77 +/- 13.35 cm H(2)O) of similar age. Patients with diaphragm weakness demonstrated significant lung volume restriction with normal DL(CO)/VA. There was no difference in resting oxygen consumption (V O(2)), carbon dioxide production (V CO(2)), minute ventilation (V E), and tidal volume (VT) between the two groups; however, a borderline difference in resting breathing frequency (f(b)) (p = 0.056) was evident. Both groups demonstrated a rise in V O(2), V CO(2), and V E during 2 min of AE anteriorly. Normal subjects demonstrated a statistically significant rise in VT but a statistically insignificant rise in f(b) during AE. In contrast, patients with diaphragm weakness demonstrated a statistically significant rise in f(b) during AE but a statistically insignificant rise in VT. In patients the observed rise in VT directly correlated with baseline Pdi(sniff) (r = 0.59, p = 0.02) and Pdi(max) (r = 0.81, p = 0.002). Both groups demonstrated a rise in Pdi during AE. The rise in Pdi during AE directly correlated to Pdi(sniff) in the patients (r = 0.69, p = 0.004). Observed end-expiratory Ppl rose during arm elevation in both the patient group and in the normal control group, but no evidence of a differential response to AE was found. In those patients with greater diaphragm weakness (Pdi(sniff) < 30 cm H(2)O), abnormal respiratory muscle function (lesser rise in Pdi) and a lesser increase in VT during AE were more evident. These data highlight the importance of diaphragm function in determining the metabolic and respiratory muscle response to arm elevation.

Semi-quantitative ventilation/perfusion scintigraphy and single-photon emission tomography for evaluation of lung volume reduction surgery candidates: description and prediction of clinical outcome

Ventilation/perfusion scans with single-photon emission tomography (SPET) were reviewed to determine their usefulness in the evaluation of lung volume reduction surgery (LVRS) candidates, and as a predictor of outcome after surgery. Fifty consecutive planar ventilation (99mTc-DTPA aerosol) and perfusion (99mTc-MAA) scans with perfusion SPET of patients evaluated for LVRS were retrospectively reviewed. Technical quality and the severity and extent of radiotracer defects in the upper and lower halves of the lungs were scored from visual inspection of planar scans and SPET data separately. An emphysema index (EI) (extent x severity) for the upper and lower halves of the lung, and an EI ratio for upper to lower lung were calculated for both planar and SPET scans. The ratios were compared with post-LVRS outcomes, 3, 6 and 12 months after surgery. All perfusion and SPET images were technically adequate. Forty-six percent of ventilation scans were not technically adequate due to central airway tracer deposition. Severity, extent, EI scores and EI ratios between perfusion and SPET were in good agreement (r = 0.52-0.68). The mean perfusion EI ratio was significantly different between the 30 patients undergoing biapical LVRS and the 17 patients excluded from LVRS (3.3+/-1.8 versus 1.2+/-0.7; P<0.0001), in keeping with the anatomic distribution of emphysema by which patients were selected for surgery by computed tomography (CT). The perfusion EI ratio correlated moderately with the change in FEV1 at 3 months (r = 0.37, P = 0.04), 6 months (r = 0.36, P = 0.05), and 12 months (r = 0.42, P = 0.03), and the transition dyspnea index at 6 months (r = 0.48, P = 0.014) after LVRS. It is concluded that patients selected to undergo LVRS have more severe and extensive apical perfusion deficits than patients not selected for LVRS, based on CT determination. SPET after aerosol V/Q imaging does not add significantly to planar perfusion scans. Aerosol DTPA ventilation scans are not consistently useful. Perfusion lung scanning may be useful in selecting patients with successful outcomes after LVRS.

Endocrinologic and metabolic complications in the intensive care unit

Critical illness provides major stresses on all body systems, including those serving important regulatory functions. Endocrinologic and metabolic abnormalities are common on presentation and during hospitalization in the intensive care unit. Some of these abnormalities are the focus of this article. The authors review abnormalities of the adrenal and thyroid glands and in the metabolism of glucose, and include a brief review of abnormalities of sodium and calcium metabolism.

Sarcoidosis presenting as a tumorlike muscular lesion. Case report and review of the literature

Sarcoid myopathy presenting as a tumorlike lesion is an exceedingly rare presentation of sarcoidosis. Concurrent extramuscular involvement is common. Chest radiographs, if abnormal, may suggest the diagnosis. Magnetic resonance imaging is the preferred study for diagnosis and follow-up of tumorous sarcoid myopathy. Optimal therapy is not clear. Favorable responses have been cited with surgery or corticosteroids (alone or in combination). Azathioprine or alternative immunosuppressive agents (for example, antimalarials or methotrexate) may have a role in corticosteroid-recalcitrant patients. The role of local radiotherapy is controversial and should be reserved for severe localized disease refractory to aggressive medical therapy.

Preoperative echocardiographic evaluation of patients referred for lung volume reduction surgery

BACKGROUND

The most efficient preoperative assessment for lung volume reduction surgery (LVRS) in patients with advanced emphysema is undefined. This study analyzed the preoperative assessment of patients by surface echocardiography (without and with dobutamine infusion), the results of which were used to exclude patients with significant pre-existing cardiac disease, a contraindication to LVRS, from the surgery.

SETTING

A university-based, tertiary care referral center.

METHODS

Patients with emphysema who met initial LVRS screening criteria underwent resting and stress surface echocardiography with Doppler imaging. Patients were evaluated prospectively for perioperative cardiac complications.

RESULTS

Between July 1994 and December 1996, 503 candidates for LVRS were evaluated. Of these, 207 patients (81.8%) who had echocardiography performed at our institution formed the primary study group. Images were adequate for the analysis of chamber sizes and function in 206 patients (99.5%) undergoing resting echocardiography, and the images were adequate for wall motion analysis in 172 of 174 patients (98.9%) undergoing functional testing. Right heart abnormalities were common (40.1%). Significant pulmonary hypertension (> 35 mm Hg) was uncommon (5 patients, 5.4%) among the 92 patients who subsequently underwent right heart catheterization. Occult ischemia, left ventricular dysfunction, and valvular abnormalities also were uncommon. Thus, although Doppler imaging estimates of right ventricular systolic pressure were imperfect, echocardiographic findings of normal right heart anatomy and function excluded significant pulmonary hypertension. Ninety patients (43%) eventually underwent LVRS (70 bilateral and 20 unilateral). A total of 13 perioperative cardiac events occurred in 10 patients, 6 of whom had undergone preoperative echocardiography. No patient suffered acute myocardial infarction or cardiac death.

CONCLUSIONS

Despite potential limitations due to severe obstructive lung disease, surface echocardiographic imaging is a feasible, noninvasive tool in this patient population to identify patients with evidence of cor pulmonale that suggests pulmonary hypertension. The routine use of surface resting and stress echocardiography for preoperative screening obviates the need for invasive right heart catheterization in many patients and results in a low incidence of significant perioperative cardiac complications.

Combined lung volume reduction and mitral valve reconstruction

Combined lung volume reduction and mitral valve reconstruction was performed in a 66-year-old man with end-stage emphysema and severe mitral regurgitation. Quality of life, pulmonary function, 6-minute walk, echocardiographic degree of mitral regurgitation, and New York Heart Association heart failure classification all improved substantially. A lung volume reduction operation can safely be combined with complex cardiac operations for patients with disabling dyspnea of a multifactorial nature.

Inhaled nitric oxide in primary pulmonary hypertension: a safe and effective agent for predicting response to nifedipine

OBJECTIVES

The purpose of this study was to assess the utility of inhaled nitric oxide (NO), a selective pulmonary vasodilator, for predicting the safety and acute hemodynamic response to high-dose oral nifedipine in primary pulmonary hypertension (PPH).

BACKGROUND

A significant decrease in pulmonary vascular resistance with an oral nifedipine challenge is predictive of an improved prognosis, and potential clinical efficacy in PPH. However, the required nifedipine trial carries significant first-dose risk of hypotension. While inhaled NO has been recommended for assessing pulmonary vasodilator reserve in PPH, it is not known whether it predicts the response to nifedipine.

METHODS

Seventeen patients with PPH undergoing a nifedipine trial were assessed for hemodynamic response to inhaled NO at 80 parts per million for 5 minutes. The nifedipine trial consisted of 20 mg of nifedipine hourly for 8 hours unless limited by hypotension or intolerable side effects. Patients were classified as responders and nonresponders with positive response defined as > or =20% reduction in mean pulmonary artery pressure (mPA) or pulmonary vascular resistance (PVR) with the vasodilator administration.

RESULTS

NO was safely administered to all participants. Seven of 17 (41.2%) responded to NO, and 8 of the 17 to nifedipine (47.1%). Nifedipine was safely administered in 14 of the 17. Three suffered either mild or severe hypotension, including one death. All NO responders also responded to nifedipine, and 9 of the 10 NO nonresponders were nifedipine nonresponders, representing a sensitivity of 87.5%, specificity of 100%, and overall predictive accuracy of 94%. All NO responders tolerated a full nifedipine trial without hypotension. There was a highly significant correlation between the effects of NO and nifedipine on PVR (r=0.67, p=0.003).

CONCLUSIONS

The pulmonary vascular response to inhaled NO accurately predicts the acute hemodynamic response to nifedipine in PPH, and a positive response to NO is associated with a safe nifedipine trial. In patients comparable with those evaluated, a trial of nifedipine in NO nonresponders appears unwarranted and potentially dangerous.

Community-acquired pneumonia

Community-acquired pneumonia remains a serious cause of morbidity and mortality, particularly in the elderly or patients with coexisting diseases. Therapeutic strategies are usually empiric, based upon demographic and epidemiologic factors, acuity and severity of illness, comorbidities, and cost constraints. Recent guidelines may be used to discriminate patients who may be treated in the outpatient setting with oral antimicrobials from patients in whom hospitalization and parenteral therapy is appropriate. Over the past decade, dramatic escalation in antimicrobial resistance among common respiratory pathogens poses obstacles to antibiotic choices. We review the microbiology of community-acquired pneumonia, and the therapeutic strategies that are clinically and cost effective.

Idiopathic pulmonary fibrosis: predicting response to therapy and survival

Idiopathic pulmonary fibrosis (IPF) is associated with significant morbidity and mortality despite aggressive therapy. Thirty-eight patients with biopsy-proven IPF were studied to identify pretreatment features that could be used to predict short-term improvement in pulmonary function and improved longer term survival. In all patients, a pretreatment clinical (dyspnea), radiographic (chest radiograph), and physiologic (pulmonary function including exercise saturation) score was generated (CRP). A high-resolution CT scan (HRCT) was independently scored by four radiologists for ground glass (CT-alv) and linear opacity (CT-fib) on a scale of 0-4. Open lung biopsy samples were scored for cellular infiltration, interstitial fibrosis, desquamation, and granulation by an experienced pulmonary pathologist. All patients were treated with 3 mo of high-dose steroids and the CRP scoring repeated. Patients were divided into three groups: responders with a greater than 10-point drop in CRP (n = 10); stable with +/- 10 point change in CRP (n = 14); and nonresponders with > 10 point rise in CRP or death (n = 14). Those responding to steroids were treated for 18 mo in a tapering fashion. In all others, steroids were tapered quickly and oral cyclophosphamide prescribed. Responders (10 of 38) had a lower age (45.1+/-4.3 yr) than nonresponders (61.4+/-3.5 yr) or those remaining stable (53.1+/-3.3 yr) (p = 0.01). Pretreatment CRP was higher in responders (58.8+/-5.6) than nonresponders (40.5+/-4.7) or stable individuals (37.6+/-4.7) (p = 0.01). Cellular infiltration score of the open lung biopsies was higher in responders (7.6+/-0.6) than stable individuals (5.7+/-0.5) (p = 0.04). The CT-alv scores were higher and CT-fib scores were lower in responders than nonresponders. Receiver operating curve (ROC) analysis was employed to identify pretreatment features of longer term survival (follow-up of 29.1+/-2.3 mo). Only CT-fib (p = 0.009) and pathology fibrosis score (p = 0.03) were able to predict mortality. A pretreatment CT-fib score > or = 2.0 demonstrated 80% sensitivity and 85% specificity in predicting survival. Those patients who did not respond to initial steroid therapy demonstrated a worse long-term survival and greater likelihood of decreased pulmonary function. We demonstrate that pretherapy pulmonary function, pathologic and radiographic parameters are different in individuals who respond to initial prednisone therapy. Only HRCT imaging and pathologic fibrosis were able to reliably predict long-term survival in patients with biopsy-proven IPF.

Diagnosing chronic obstructive pulmonary disease. The importance of differentiating asthma, emphysema, and chronic bronchitis

In patients with chronic obstructive pulmonary disease (COPD), a thorough understanding on the clinician's part of the pathophysiologic basis of airflow limitation greatly enhances decisions regarding care. Differences in prognosis among the major types of COPD have become clear, and identification of airway inflammation has dramatically altered medical therapy. Dr Martinez, who coordinated this symposium, here explains the importance of judiciously applying findings from history taking, physical examination, laboratory studies (particularly pulmonary function testing), and radiographic studies to all aspects of disease management. The remaining four symposium articles address specific avenues for treatment of emphysema and chronic bronchitis.

Mycophenolate mofetil for obliterative bronchiolitis syndrome after lung transplantation

BACKGROUND

The development of obliterative bronchiolitis after lung transplantation portends a poor long-term outcome because of progressive decline in allograft function. There are currently no effective means of treating this condition.

METHODS

Thirteen patients in whom obliterative bronchiolitis syndrome developed after lung transplantation were treated with mycophenolate mofetil, an antimetabolite immunosuppressant, at a dose of 1.5 g orally twice daily. Patients were followed up clinically and with pulmonary function testing.

RESULTS

Duration of mycophenolate mofetil therapy ranged from 1 week to 24 months (mean duration, 11.4 months). Pulmonary function test results stabilized in the majority of patients with no significant further decline in forced expiratory volume in 1 second. Two patients died of progressive obliterative bronchiolitis, 1 patient is alive with progressive disease, and 1 patient died of an acute infection. The drug was discontinued in 2 additional patients. In no patient did severe leukopenia or cytomegalovirus infection develop; 1 patient had a fungal infection, and 7 patients experienced gastrointestinal side effects.

CONCLUSIONS

In the setting of obliterative bronchiolitis syndrome, mycophenolate mofetil is generally well tolerated and is associated with stabilization of pulmonary function test results. These findings suggest that the otherwise progressive process of obliterative bronchiolitis can be slowed.

Thin-section CT obtained at 10-mm increments versus limited three-level thin-section CT for idiopathic pulmonary fibrosis: correlation with pathologic scoring

OBJECTIVE

The purpose of our study was to determine if three-level thin-section CT depicts idiopathic pulmonary fibrosis (IPF) pathology as accurately as CT obtained at 10-mm increments throughout the entire lungs.

SUBJECTS AND METHODS

Thin-section (1.0- to 1.5-mm) images at 10-mm increments were obtained and scored prospectively in 25 consecutive patients with newly diagnosed IPF who were participating in a Special Center of Research grant for interstitial lung disease. Each patient's lobe was scored by four thoracic radiologists on a scale of 0-5 for both ground-glass attenuation and fibrosis. The radiologists used three images (limited CT) and also used the entire data set (complete CT). CT scores were compared with pathology scores from 67 open and thoracoscopic biopsies. Limited and complete scores were compared with each other (Pearson correlation coefficient). Interobserver variation in the CT scoring system was assessed using kappa values.

RESULTS

CT fibrosis scores strongly correlated with pathology fibrosis scores for complete (r = .53, p = .0001) and limited (r = .50, p = .0001) CT. CT ground-glass scores correlated with the histologic inflammatory scores for each lobe on complete (r = .27, p = .03) and limited (r = .26, p = .03) CT. The desquamative subcomponent of the pathology inflammatory score had the highest correlation with the CT ground-glass scores (complete: r = .29, p = .01; limited: r = .33, p = .007). Good interobserver agreement existed for both the alveolar and fibrosis components of the CT scoring system (kappa values ranging from .51 to .83) for each lobe of the lung on limited and complete CT.

CONCLUSION

Limited thin-section CT reveals the pathologic changes associated with IPF as well as CT obtained at 10-mm increments. An added advantage of limited thin-section CT is that it exposes patients to less radiation.

Pulmonary smooth muscle proliferation occurring after lung transplantation

We report the first example of smooth-muscle proliferations occurring in an allograft lung implanted in a recipient who had end-stage emphysema. Smooth-muscle proliferations were detected 46 months following transplantation in a 53-year-old woman. The lesions involved the airways and were bronchoscopically undetectable. Posttransplant smooth-muscle tumors have been described in liver transplant patients and are thought to be due to Epstein-Barr virus. Evidence of virus infection was not found in the current case.

Lung-volume reduction improves dyspnea, dynamic hyperinflation, and respiratory muscle function

Lung-volume reduction surgery (LVRS) improves static lung elastic recoil in selected patients with severe chronic obstructive pulmonary disease (COPD). This explains the increase in FEV1 in many COPD patients who undergo LVRS, but fails to explain clinical improvement in those without changes in FEV1. We prospectively evaluated 17 patients after pulmonary rehabilitation but prior to and again at least 3 mo after bilateral LVRS done via median sternotomy. In addition to pulmonary function, lung elastic recoil, walking distance, and exercise capacity, we evaluated static and dynamic respiratory muscle (RM) function, and dyspnea. In 12 patients we also quantified dynamic hyperinflation (end-expiratory and end-inspiratory lung volume [EELV and EILV, respectively]). After LVRS, FEV1 rose from 26.7 +/- 1.8 to 39.0 +/- 3.7% predicted (p < 0.004), whereas TLC dropped from 134.7 +/- 4.8 to 118.3 +/- 4.4% predicted (p < 0.0002), and RV from 239.6 +/- 14.8 to 180.3 +/- 8.7% predicted (p < 0.0002). Isowork dyspnea decreased as assessed with a visual analogue scale (VAS) (79.6 +/- 5.2 versus 49.3 +/- 7.5 mm, p < 0.005) and the Borg scale (7.1 +/- 0.6 versus 3.5 +/- 0.6, p = 0.002). Walking distance improved significantly and, in the 12 patients in whom they were measured, EELV and EILV decreased at rest and at isowork. Maximal transdiaphragmatic pressure rose from 67.1 +/- 8.3 to 92.0 +/- 7.5 cm H2O (p < 0.03). Resting RM function changed little, but at isowork improved significantly after LVRS. Excluding one outlier, there was a strong linear correlation between the change in Borg-scale score at equivalent work loads before and after LVRS and the change in EELV (% predicted TLC, r = 0.75, p < 0.001), as well as between the change in Borg-scale score and the absolute decrease in end-expiratory pleural pressure (Ppl(e)) (r = 0.78, p = 0.004). Successful LVRS improves not only lung recoil, but also respiratory muscle function, and reduces dynamic hyperinflation. These changes help explain the decreased dyspnea and improved exercise capacity seen after LVRS, and add to current understanding of the mechanisms by which this procedure may help selected patients with severe emphysema.

Arm training reduces the VO2 and VE cost of unsupported arm exercise and elevation in chronic obstructive pulmonary disease

BACKGROUND

Patients with severe chronic obstructive pulmonary disease (COPD) may develop dyspnea with minimal arm activity, thoracoabdominal dyssynchrony with unsupported arm exercise (UAEX) and increased oxygen uptake (VO2), and minute ventilation (VE) with simple unsupported arm elevation (UAE) and UAEX. We investigated whether unsupported arm training, as the only form of exercise, could decrease the VO2 and VE cost (percentage increase from resting baseline) associated with unsupported arm elevation and exercise, respectively.

METHODS

Twenty-six patients with severe COPD were randomized to 21-24 sessions of unsupported arm (ARMT) or low-intensity resistive breathing (RBT) training as the only form of exercise. Patients were studied before and after training using a metabolic cart and esophageal and gastric pressures to evaluate metabolic and respiratory muscle function.

RESULTS

After ARMT, the VO2 (58% vs 38% increase, P < 0.05) and VE (41% v. 21% increase, P < 0.05) cost for UAEX at exercise isotime decreased and endurance time increased. Similarly the VO2 (25% vs 18% increase, P < 0.05) cost decreased and VE no longer increased in response to 2 minutes of UAE after ARMT. The RBT group showed no such change. No improvement in ventilatory load or respiratory muscle function could be identified to explain the physiologic changes observed. After ARMT, mean inspiratory flow (VT/TL), a measure of central respiratory drive, was reduced during UAEX and the expected increase during UAE did not occur.

CONCLUSION

We conclude that arm training reduces the VO2 and VE cost of UAE and UAEX, possibly through improved synchronization and coordination of accessory muscle action during unsupported arm activity.

Dose escalation for non-small cell lung cancer using conformal radiation therapy

PURPOSE

Improved local control of non-small cell lung cancer (NSCLC) may be possible with an increased dose of radiation. Three-dimensional radiation treatment planning (3D RTP) was used to design a radiation therapy (RT) dose escalation trial, where the dose was determined by (a) the effective volume of normal lung irradiated, and (b) the estimated risk of a complication. Preliminary results of this trial were reviewed.

METHODS AND MATERIALS

A graph of the iso-normal tissue complication probability (NTCP) levels associated with a dose and effective volume (V(eff)) was derived, using normal tissue parameters derived from the literature. This led to a dose escalation schema, where patients were sorted into 1 of 5 treatment bins, determined by the V(eff) of the best possible treatment plan. The starting doses ranged from 63 to 84 Gy. Each treatment bin was then escalated separately, as in Phase I dose escalation fashion, with Grade > or = 3 radiation pneumonitis defined as dose limiting. To allow for dose escalation, we required patient follow-up to be > or = 6 months for at least three patients. 3D treatment planning was used to irradiate only the radiographically abnormal areas, with 2.1 Gy (corrected for lung inhomogeneity)/day. Clinically uninvolved lymph nodes were not treated prophylactically.

RESULTS

A total of 48 NSCLC patients have been treated (Stage I/II: 18 patients; Stage III: 28 patients; mediastinal recurrence postsurgery: 2 patients). No radiation pneumonitis has been observed in the 30 patients currently evaluable beyond the 6-month time point. All treatment bins have been escalated at least once. Current doses in the five treatment bins are 69.3, 69.3, 75.6, 84, and 92.4 Gy. None of the 15 evaluable patients in any bin with > or = 30% NTCP experienced clinical radiation pneumonitis, implying that the actual risk is < 20% (beta error rate 5%). Despite the observation of the clinically negative lymph nodes at high risk, there has been no failure in the untreated mediastinum as the sole site of first failure. Three of 10 patients receiving > or = 84 Gy have had biopsy proven residual or locally recurrent disease.

CONCLUSION

Successful dose escalation in a volume-dependent organ can be performed using this technique. By incorporating the effective volume of irradiated tissue, some patients have been treated to a total dose of radiation over 50% higher than traditional doses. The literature-derived parameters appear to overestimate pneumonitis risk with higher volumes. There has been no obvious negative effect due to exclusion of elective lymph node radiation. When completed, this trial will have determined the maximum tolerable dose of RT as a single agent for NSCLC and the appropriate dose for Phase II investigation.

Bronchoalveolar lavage neutrophilia is associated with obliterative bronchiolitis after lung transplantation: role of IL-8

Obliterative bronchiolitis (OB) is a devastating complication in lung transplantation. We postulated that the pathogenesis of OB is mediated, in part, by neutrophils. We serially collected bronchoalveolar lavage (BAL) fluid from lung transplant recipients. Patients were divided into two groups depending on the presence or absence of OB. Samples from patients who never developed OB were further divided according to whether rejection was present. These samples were labeled healthy or rejection. Samples from patients who developed OB were divided according to whether the sample was obtained before (future OB) or at the time of diagnosis of OB (OB). The OB group, as compared with the healthy and rejection group, had significantly elevated neutrophil counts (3.9 x 10(5) +/- 1.8 x 10(5) vs 0.3 x 10(5) +/- 0.07 x 10(5) and 0.4 x 10(5) +/- 0.1 x 10(5), respectively, p < 0.01 for both) and levels of IL-8 (3131 +/- 1468 pg/ml vs 240 +/- 62 pg/ml and 172 +/- 47 pg/ml, p < 0.01 for both). Furthermore, we demonstrated immunolocalization of IL-8 associated with alpha smooth muscle actin-positive cells in the peribronchial region of OB. To confirm that the IL-8 present in BAL fluid from patients with OB was bioactive, we performed neutrophil chemotaxis experiments that showed that IL-8 accounted for a significant amount of the neutrophil chemotactic activity. We also found a trend toward higher levels of neutrophils and IL-8 in BALs from the future OB as compared with the healthy group (7.1 x 10(4) +/- 4.2 x 10(4) vs 3.4 x 10(4) +/- 0.7 x 10(4) and 500 +/- 306 pg/ml vs 240 +/- 62 pg/ml). In conclusion, we have provided the novel observation that in lung transplant recipients with OB, neutrophilia is present and highly correlated with the presence of IL-8.

Bronchoalveolar lavage neutrophilia is associated with obliterative bronchiolitis after lung transplantation: role of IL-8

Obliterative bronchiolitis (OB) is a devastating complication in lung transplantation. We postulated that the pathogenesis of OB is mediated, in part, by neutrophils. We serially collected bronchoalveolar lavage (BAL) fluid from lung transplant recipients. Patients were divided into two groups depending on the presence or absence of OB. Samples from patients who never developed OB were further divided according to whether rejection was present. These samples were labeled healthy or rejection. Samples from patients who developed OB were divided according to whether the sample was obtained before (future OB) or at the time of diagnosis of OB (OB). The OB group, as compared with the healthy and rejection group, had significantly elevated neutrophil counts (3.9 x 10(5) +/- 1.8 x 10(5) vs 0.3 x 10(5) +/- 0.07 x 10(5) and 0.4 x 10(5) +/- 0.1 x 10(5), respectively, p &lt; 0.01 for both) and levels of IL-8 (3131 +/- 1468 pg/ml vs 240 +/- 62 pg/ml and 172 +/- 47 pg/ml, p &lt; 0.01 for both). Furthermore, we demonstrated immunolocalization of IL-8 associated with alpha smooth muscle actin-positive cells in the peribronchial region of OB. To confirm that the IL-8 present in BAL fluid from patients with OB was bioactive, we performed neutrophil chemotaxis experiments that showed that IL-8 accounted for a significant amount of the neutrophil chemotactic activity. We also found a trend toward higher levels of neutrophils and IL-8 in BALs from the future OB as compared with the healthy group (7.1 x 10(4) +/- 4.2 x 10(4) vs 3.4 x 10(4) +/- 0.7 x 10(4) and 500 +/- 306 pg/ml vs 240 +/- 62 pg/ml). In conclusion, we have provided the novel observation that in lung transplant recipients with OB, neutrophilia is present and highly correlated with the presence of IL-8.

Lung mechanics and dyspnea after lung transplantation for chronic airflow obstruction

Single lung transplantation (SLT) is widely used to treat chronic airflow obstruction (CAO). During exercise the native lung should increase end-expiratory lung volume (EELV) and result in a different respiratory sensation compared with double lung transplantation (DLT). Eight SLT recipients and 12 DLT recipients demonstrated a similar maximal work load and achieved VO2. VEmax/MVV was 67.2 +/- 4.0% in SLT recipients and 48.5 +/- 3.6% in DLT recipients (p = 0.003). All SLT recipients demonstrated an increase in EELV during exercise, which was seen in only three of 12 DLT recipients. The change in absolute EELV from rest to peak exercise was different between SLT recipients (+0.37 +/- 0.10 L) and DLT recipients (-0.10 +/- 0.06, p = 0.0002). Tidal flow volume loop analysis demonstrated encroachment of the expiratory limb in four of seven SLT patients but in only one of 12 DLT recipients. A lesser peak breathlessness in DLT recipients approached statistical significance (p = 0.051), although the relation of respiratory sensation versus VE or VO2% predicted did not differ between the two groups. EELV increases in SLT recipients at peak exercise, although overall aerobic response is preserved and respiratory sensation is similar.

Endobronchial ultrasound-guided needle aspiration of mediastinal adenopathy

We conducted a randomized, controlled trial to prospectively confirm that ultrasound-directed transbronchial needle aspiration (USTBNA) results in: (1) improved sensitivity for detecting lymph nodes involved with neoplasm, and (2) a decreased number of aspirates needed to achieve a diagnosis as compared with standard transbronchial needle aspiration (TBNA). The study was conducted in a tertiary medical center on patients undergoing fiberoptic bronchoscopy in the evaluation of enlarged mediastinal lymph nodes. USTBNA or TBNA were followed by rapid, on-site cytopathology examination of the collected specimens. Measurements included the (1) age and sex of the patient, prior diagnosis of cancer, nodal short-axis diameter and node location as determined by computerized tomography (CT), and endobronchial abnormalities at bronchoscopy; (2) number, order, and location of transbronchial aspirates and results of on-site evaluation; (3) results of surgical exploration in patients with negative transbronchial needle aspiration; (4) sensitivity, specificity, and diagnostic accuracy of USTBNA and TBNA; (5) number of aspirates required for successful lymph node aspiration as well as for a diagnosis of cancer for both USTBNA and TBNA; and (6) multiple logistic regression analysis to determine the significance of combinations of clinical predictors and needle aspirate results. Eighty-two bronchoscopic examinations were performed on 80 patients. We found no significant difference between USTBNA and TBNA in sensitivity (82.6% versus 90.5%, respectively), specificity (100% for both), or diagnostic accuracy (86.7% versus 91.7%, respectively). The sensitivity, specificity, and diagnostic accuracy of USTBNA and TBNA were similarly high, regardless of node location (paratracheal or subcarinal). A decrease in the number of aspirates required for lymph node sampling approached statistical significance for all USTBNAs as compared with TBNAs (2.03 +/- 0.19 versus 2.62 +/- 0.25, p = 0.06), but this was not demonstrated for the number required to confirm cancer (1.95 +/- 0.47 versus 2.68 +/- 0.21, p = 0.17). The number of aspirates to successful lymph node aspiration decreased with USTBNA versus TBNA in paratracheal lymph nodes (2.00 +/- 0.20 versus 2.91 +/- 0.34, p = 0.03), but not to a diagnosis of cancer (1.93 +/- 0.25 versus 3.00 +/- 0.58, p = 0.11). No difference was seen in the number of aspirates for subcarinal nodes. The number of TBNA attempts for paratracheal lymph node sampling was inversely correlated with node size (r = 0.48, p = 0.02). No such relation was seen with USTBNA of paratracheal nodes (r = 0.09, p = 0.66), TBNA of subcarinal nodes, or USTBNA of subcarinal nodes. A similar relation was seen between the number of aspirates to a diagnosis of cancer. On multiple logistic regression analysis, a positive transbronchial aspirate was associated only with a larger lymph node and history of prior cancer. We conclude that: (1) in the setting of on-site cytopathology, transbronchial needle aspiration has a high sensitivity, specificity, and diagnostic accuracy in the evaluation of enlarged mediastinal lymph nodes suspected of harboring malignancy; (2) mediastinal anatomy, including vascular structures and lymph nodes, is clearly imaged with endobronchial ultrasonography; (3) a greater short-axis diameter of the mediastinal lymph node and history of a prior malignancy increase the likelihood of a positive transbronchial aspiration; (4) USTBNA exhibits a similarly high diagnostic yield to TBNA in the setting of rapid on-site cytopathology evaluation; (5) USTBNA decreases the number of aspirates required for paratracheal lymph node sampling, which may be particularly useful in sampling smaller paratracheal nodes or at institutions that do not utilize rapid on-site cytopathology evaluation.

Transthoracic needle aspiration in patients with severe emphysema. A study of lung transplant candidates

PURPOSE

To describe the risks of transthoracic needle aspiration (TTNA) in a population of patients with severe lung disease: candidates for lung transplantation.

MATERIALS AND METHODS

Eight of 190 patients evaluated for lung transplantation underwent TTNA of nine pulmonary nodules (mean diameter, 14 mm; range, 0.8 to 2.2 cm). We evaluated pneumothorax rate, chest tube rate, duration of placement, and pulmonary function test results.

RESULTS

All patients had emphysema; two had alpha 1-antitrypsin deficiency. The mean FEV1 of all patients was 0.64 L (22% of predicted; range, 17 to 28%), indicating severe air-flow obstruction. Six patients required a chest tube (50%); three chest tubes were placed emergently on the CT scanner table. Three patients required a second chest tube for persistent air leak. Tubes were in place for 1 to 22 days (mean, 10 days). One patient had chest tubes for 22 days and required intubation.

CONCLUSION

TTNA in patients with marked emphysema is complicated by a high incidence of pneumothorax, rapid development of tension pneumothorax and chest tube placement. Since nodules in lung transplant candidates may represent bronchogenic carcinoma, serial CT scans to demonstrate lesion stability or growth, or thoracoscopic resection should be considered as an alternate approach to TTNA to avoid the significant morbidity of the procedure in these patients.

Risk of pneumothorax in CT-guided transthoracic needle aspiration biopsy of the lung

PURPOSE

To determine risk factors for pneumothorax and chest tube placement associated with computed tomography (CT)-guided transthoracic needle aspiration biopsy (TNAB) of the lung.

METHODS

One hundred twenty-one consecutive CT-guided TNAB procedures were performed in 117 patients. Patient age, sex, number of needle passes and pleural planes traversed, lesion size, distance of lesion from the pleura, and results of pulmonary function tests were analyzed as single and multiple dependent variables for pneumothorax and chest tube placement.

RESULTS

Pneumothorax occurred in 54 of 121 procedures (44.6%); a chest tube was required in 18 cases (14.9%). Increased lesion depth was the most significant predictor of pneumothorax (P = .002). Smaller lesion size also correlated with increased risk of pneumothorax (P = .04). Among patients with pneumothorax, a significantly higher frequency of chest tube placement was seen in those with severe obstructive lung disease, as measured by percentage of predicted FEV1 (forced expiratory volume in 1 second) (51% in patients requiring a chest tube vs 81% in those not requiring a chest tube, P = .006) and FEV1/FVC (forced vital capacity) (x100) (45% vs 66%, P = .001).

CONCLUSION

Increased lesion depth and smaller lesion size correlated strongly with the development of pneumothorax. Once pneumothorax occurred, chest tube placement related to the severity of the patient's obstructive lung disease.

Influence of sample number and biopsy site on the histologic diagnosis of diffuse lung disease

BACKGROUND

Although open biopsy is considered the optimal method for obtaining lung tissue for the diagnosis of diffuse infiltrative pulmonary disorders, there are no universally established guidelines concerning biopsy site selection and the ideal number of tissue samples. Relatively few investigations have been devoted to the influence exerted by the site and number of biopsy samples on the histologic diagnosis.

METHODS

Seventy-seven open biopsy samples obtained from different lobes of 28 patients with idiopathic pulmonary fibrosis were analyzed. The histopathologic features were evaluated semiquantitatively and the results from each sample compared with those of the other samples obtained from each patient.

RESULTS

Statistically significant differences in histopathologic features were not observed between samples.

CONCLUSIONS

A single generous (2 cm or greater diameter) sample, obtained from a representative region of the radiographically most involved lobe, will suffice for diagnostic and evaluation purposes.

Preoperative examination of lung transplant candidates: value of chest CT compared with chest radiography

OBJECTIVE

The purpose of our study was to determine the usefulness of CT in examining candidates for lung transplantation to detect cancer not visible on plain chest radiographs (a finding that would exclude a patient from transplantation) and to determine which lung is more severely diseased to aid in the decision of which side to transplant.

MATERIALS AND METHODS

We reviewed the chest radiographs and CT scans of 190 transplant candidates during a 3-year period for findings suggestive of neoplasm, including lung nodules and atelectasis; we also reviewed the symmetry of disease. In the latter category, patients with primary pulmonary hypertension, Eisenmenger's complex (pulmonary vascular, not parenchymal, disease), and cystic fibrosis (for which bilateral transplantation is performed) were excluded. A total of 190 plain chest radiographs, 180 thin-section CT scans, and 31 standard CT scans were reviewed retrospectively.

RESULTS

Plain chest radiographs revealed 20 noncalcified nodules; 13 were 8 mm or more in diameter, and 7 were less than 8 mm. CT scans revealed 66 noncalcified nodules; 37 were 8 mm or more in diameter, and 29 were less than 8 mm. Eight non-calcified nodules seen on plain chest radiographs were either absent on CT scans (and follow-up plain chest radiographs) or appeared calcified on CT scans. Solitary nodules in three patients proved to be bronchogenic carcinomas; two of these lesions were identified only on CT scans. CT prompted a change in the determination of which lung was more severely diseased from that made on the basis of plain radiography for 27 of 169 patients (16%) evaluated. Of the 45 patients who subsequently underwent transplantation, CT prompted a change in the determination of which side to transplant from that made on the basis of plain radiography for 4 patients (9%).

CONCLUSION

CT provides additional information to supplement plain radiography in the examination of lung transplant candidates. This information can alter patient management, particularly when bronchogenic carcinoma is detected, and enable a better determination of which lung is more severely diseased to aid in the decision of which lung to transplant for single-lung transplantation.

Inotropic and chronotropic effects of 4-(4'-n-butylaniline)-7,8- dimethoxy-5H-pyrimido[5,4-b]indole in guinea-pig atria

Cardiotonic effect of 4-(4'-n-butylaniline)-7,8-dimethoxy- 5H-pyrimido[5,4-b]indole (B11) was investigated in isolated cardiac tissue preparations. The action of this agent on force of contraction, beating frequency and cyclic nucleotide phosphodiesterase (PDE) activity was studied. Amrinone was used for comparison. B11 produced concentration-dependent (5 x 10(6)-1 x 10(-4)M) positive inotropic and positive chronotropic responses in guinea-pig atrial tissues. The potency of B11 was greater than that of amrinone. The cardiotonic effects of B11 were not modified by beta-adrenoceptor blockade. Carbachol inhibited the positive inotropic effect of B11. The activity of B11 was increased in desensitized left atrial tissues. B11 inhibited the activities of PDE isoenzymes (type I, II, IV and V) from dog heart ventricle and PDE type IV from guinea-pig heart ventricle nonselectively. It is concluded that B11 possesses potent positive inotropic activity in guinea-pig atria, and the effect is probably mediated by a non-selective inhibition of PDE activity.

The sensitivity of high-resolution CT in detecting idiopathic pulmonary fibrosis proved by open lung biopsy. A prospective study

OBJECTIVES

To assess the sensitivity of high-resolution chest computed tomography (HRCT) in detecting idiopathic pulmonary fibrosis proved by biopsy specimen. To determine the degree of physiologic and pathologic abnormalities in patients with idiopathic pulmonary fibrosis who have a false-negative HRCT.

DESIGN

Prospective 2-year study.

SETTING

Tertiary care university hospital.

PATIENTS

All patients with dyspnea and suspected interstitial lung disease referred to the University of Michigan for enrollment in the Idiopathic Pulmonary Fibrosis Specialized Center of Research (SCOR) protocol were included; 25 underwent open lung biopsy and formed the final study group.

MEASUREMENTS

All patients underwent physiologic (pulmonary function, gas exchange, and exercise testing), radiologic (chest x-ray film and HRCT), and pathologic assessments (bronchoscopic and open lung biopsy). The results of HRCT were prospectively compared with results of standard pulmonary function tests, cardiopulmonary exercise testing, and open lung biopsy.

RESULTS

Of 25 patients who had both HRCT and open lung biopsy, 3 patients (12%) had HRCTs that demonstrated no evidence of interstitial lung disease. These three patients had less severe disease based on clinical, radiographic, and physiologic (CRP) scores, gas exchange abnormalities, and pathologic scoring of open lung biopsy specimens, compared with those with an abnormal HRCT.

CONCLUSION

We conclude that in the evaluation of patients with dyspnea and abnormal results of pulmonary function studies, a normal HRCT does not exclude early and clinically significant interstitial lung disease. In our patient population, physiologic testing was more sensitive than HRCT in detecting mild abnormalities in patients with idiopathic pulmonary fibrosis proved by biopsy specimen.

Synthesis and anti-HIV activity of 1,1'-dideoxygossypol and related compounds

1,1'-Dideoxygossypol (DDG), 1,1'-dideoxygossylic acid (DDGA), 8-deoxyhemigossypol (DHG), and 8-deoxyhemigossylic acid (DHGA) were synthesized and tested for their ability to inhibit the replication of HIV in vitro. The EC50 for DDGA was < 1 microM, and its threshold cytotoxicity was approximately 20 microM. DDG was less effective than DDGA against HIV and showed considerable toxicity at 5 microM. DHGA was ineffective against HIV and had very low cytotoxicity. DHG showed some anti-HIV activity, but the threshold cytotoxicity was 5 microM. The dissociation constants for the binding of the four compounds to human serum albumin were determined by fluorescence quenching titrations, and all four were found to have much lower affinities for albumin than the parent compound gossypol.

Substrate specificity of human aldose reductase: identification of 4-hydroxynonenal as an endogenous substrate

Aldose reductase, which catalyzes the reduction of glucose to sorbitol as part of the polyol pathway, has been implicated in the development of diabetic complications and is a prime target for drug development. However, aldose reductase exhibits broad specificity for both hydrophilic and hydrophobic aldehydes, which suggests that aldose reductase may also be a detoxification enzyme. Several series of structurally related aldehydes were compared as substrates in order to deduce the structural features that result in low Michaelis constants. Aldehydes that contain an aromatic ring are generally excellent substrates, consistent with crystallographic data which suggest that aldose reductase possesses a large hydrophobic substrate binding site. However, there is little discrimination among different aromatic aldehydes. In addition, small hydrophilic aldehydes exhibit low Km values if the alpha-carbon is oxidized. Analysis of the binding of NADPH by fluorescence quenching techniques indicates that aldose reductase exhibits higher affinity for NADPH than NADP, suggesting that this enzyme is normally primed for reductive metabolism. Thus aldose reductase appears to have evolved to catalyze the reduction of a very broad range of aldehydes. Structural features of substrates that bind to aldose reductase with low Km values were used to identify potential endogenous substrates. 4-Hydroxynonenal, a reactive alpha-beta unsaturated aldehyde produced during oxidative stress, is an excellent substrate (Km = 22 microM, kcat/Km = 4.6 x 10(6) M-1 min-1). Reductive metabolism of endogenous aldehydes in addition to glucose, catalyzed by aldose reductase, may play an important role in the development of diabetic complications.