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In patients dying with acute lung injury, interstitial mesenchymal cells migrate into the airspace where they replicate and deposit connective tissue. We therefore hypothesized that peptides capable of promoting mesenchymal cell migration and replication would be present in the alveolar airspace. To examine this hypothesis, patients with severe acute diffuse lung injury (n = 26) underwent bronchoalveolar lavage. Acutely ill patients without lung injury served as controls (n = 12). Recovered effluent was examined for mesenchymal cell growth-promoting and migration-promoting activity. Lavage cell supernates from both patients and controls were devoid of bioactivity. However, substantial growth-promoting and migration-promoting activity was present in lavage fluid from nearly every patient, whereas little or none was present in fluid from controls. Characterization of the bioactivity indicated a significant proportion consisted of three peptides related to PDGF: (a) a 14-kD peptide that shared with PDGF several biophysical, biochemical, receptor-binding, and antigenic properties; (b) a 29-kD peptide that appeared identical to PDGF of platelet origin; and (c) a 38-kD peptide that was biophysically and antigenically similar to PDGF. These data indicate that peptide moieties are present in the airspace of patients after acute lung injury that can signal mesenchymal cell migration and replication.

In patients who die after severe acute lung injury, a dramatic fibroproliferative response occurs within the alveolar air space, interstitium, and microvessels. Profound shunt physiology, dead space ventilation, and pulmonary hypertension are the physiologic consequences of this fibroproliferative response. The anatomic pattern of the response is unique within each alveolar compartment. For example, the air space is obliterated by granulation tissue, with replicating mesenchymal cells, their connective tissue products, and an expanding network of intra-alveolar capillaries. In contrast, the vascular fibroproliferative response is dominated by mesenchymal cell replication and connective tissue deposition within the walls of microvessels. Despite the unique anatomic features of these fibroproliferative processes, the regulatory signals involved are likely to be similar. Although our current understanding of the signals regulating the fibroproliferative response to acute lung injury is limited, inferences can be made from in vitro studies of mesenchymal cell behavior and several better understood fibroproliferative processes, including wound healing and chronic fibrotic lung diseases. As clinicians, our future ability to enhance effective lung repair will likely utilize therapeutic strategies specifically targeted to the signals that regulate the fibroproliferative process within the alveolar microenvironment.

Five types of oculocutaneous albinism and two types of ocular albinism were found among 349 Puerto Rican albinos. The most prevalent type of albinism was the Hermansky-Pudlak syndrome (HPS). HPS was observed in five of every six albinos in Puerto Rico. The prevalence of HPS was highest in the northwestern quarter of the island, affecting approximately one in 1,800 persons, and approximately one in 22 are carriers of the gene. HPS is an autosomal recessively inherited triad of a tyrosinase-positive type of albinism, a hemorrhagic diathesis due to storage pool deficient platelets and accumulation of ceroid in tissues. The pigmentary phenotype of HPS albinos resembled that of any other type of oculocutaneous or ocular albinism. The most reliable method of diagnosing HPS is by a deficiency of platelet dense bodies observed by electron microscopy. The accumulation of ceroid in the tissues is associated with fibrotic restrictive lung disease and granulomatous enteropathic disease. The enteropathic disorder resembles Crohn's disease and with few exceptions, had its onset after 13 years of age. The major causes of death were fibrotic restrictive pulmonary disease, hemorrhagic episodes and sequelae of granulomatous enteropathic disease. Menometrorrhagia was common in women with HPS. No immune deficiency was found in HPS patients. The majority of patients with HPS had visual acuities of 20/200 or worse and consequently were legally blind. Albinos of all types, including HPS, lacked binocular vision due to nearly complete crossing of the optic tracts.

Study Objective: To determine the efficacy of intravenous aminophylline in the treatment of patients hospitalized for exacerbation of chronic obstructive pulmonary disease., Design: Randomized, double-blind, placebo-controlled trial during the first 72 hours of hospitalization., Patients: Thirty patients admitted from the emergency room or walk-in clinic with the primary diagnosis of an exacerbation of chronic obstructive pulmonary disease. Twenty-eight patients completed the study; 2 patients, 1 receiving placebo and 1 receiving aminophylline, were removed from the study because of respiratory failure requiring mechanical ventilation., Interventions: PATIENTS received either intravenous aminophylline or placebo, in addition to nebulized, inhaled 0.3 mL of a 5% solution every 6 hours; methylprednisolone, 0.5 mg/kg body weight every 6 hours intravenously; ampicillin, 500 mg orally every 6 hours (tetracycline or trimethoprim-sulfamethoxazole were substituted in penicillin-allergic patients); and supplemental oxygen as needed. Aminophylline infusion rates were adjusted by an unblinded investigator to achieve theophylline levels of 72 to 83 mumol/L. Changes were also made in placebo infusion rates to maintain the double-blind design., Measurements and Main Results: The forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) before and after metaproterenol inhalation were measured twice daily by a blinded investigator, who also administered a verbal dyspnea index with a scale of 1 to 10 and questioned patients regarding possible side effects of treatment (tremor, palpitations, nausea, or vomiting). Arterial blood gas measurements at 72 hours were compared with those obtained on admission. Significant improvements in FEV1 and FVC measured before and after metaproterenol treatment and in dyspnea occurred over time in both treatment groups (p less than 0.05 for all measurements). However, there were no significant differences between the placebo and aminophylline groups in any of the spirometric measurements or the dyspnea indices (p greater than 0.5 in all five analyses). The mean increases (+/- SE) in Po2 of 1.9 (+/- 0.5) kPa with placebo and 1.7 (+/- 0.7) kPa with aminophylline and the mean decreases in PCO2 of 0.5 (+/- 0.4) kPa with placebo and 1.2 (+/- 0.4) kPa with aminophylline were not significantly different (p greater than 0.6 for PO2, p greater than 0.2 for PCO2).(ABSTRACT TRUNCATED AT 400 WORDS)

Studies of ceroid associated lesions in Hermansky-Pudlak syndrome (HPS) indicate that restrictive lung disease and granulomatous gastrointestinal lesions are among the most frequent and account for 60% of the deaths of the patients. No defects in the immune system in HPS were found. Histological, ultrastructural and chemical studies show accumulation of non-biodegradable ceroid in tissue cells and associated macrophages of HPS patients. There is no known degradative pathway for ceroid. Ceroid is eliminated from cells by exocytosis. Wild type and pale eared mice treated with leupeptin, which inhibits exocytosis, accumulate ceroid in organ cells in the same sequence seen in HPS. Young HPS patients without significant pulmonary function deficits were lavaged, the macrophages examined by TEM and tested for platelet derived growth factor. Macrophages contained ceroid and 7/12 patients had 27 +/- 42 units of PDGF bioactivity compared to zero activity in controls. Purified ceroid was fed to macrophages lavaged from the lungs of non-smoking control subjects. Prior to feeding, less than 5% of cells contained one or two small yellow-orange autofluorescent granules resembling ceroid. After feeding, approximately 20% of control cells had ingested ceroid, but PDGF was not increased. The immunologic and histologic studies and the production of PDGF by macrophages which precedes lung fibrosis all point to a central role of the macrophage in these lesions. These studies did not distinguish whether the macrophages ingested ceroid from other cells, or whether ceroid is produced intrinsically by the HPS macrophage.

Intravascular lymphomatosis is a rare lymphoma characterized by proliferation of malignant cells within the lumen of small blood vessels. We describe a case of intravascular lymphomatosis resulting in pulmonary hypertension, hypoxemia, and dyspnea. This lymphoma occasionally responds to combination chemotherapy, suggesting that pulmonary hypertension secondary to intravascular lymphomatosis may be reversible. Intravascular lymphomatosis should be considered in the differential diagnosis of pulmonary hypertension.

Pleuropulmonary disease is a common feature of the following connective tissue diseases: systemic lupus erythematosis (SLE), rheumatoid arthritis (RA), progressive systemic sclerosis (PSS), mixed connective tissue disease (MCTD), polymyositis/dermatomyositis (PM/DM), and Sjogren's syndrome (SS). Features common to most of these disorders include pleurisy with effusion and interstitial lung disease. Pleural effusions caused by SLE and RA have certain characteristics on pleural fluid analysis that aid in diagnosis, but infection and other causes of effusion must be excluded. Interstitial lung involvement is usually indolent in onset, but a more rapidly progressive course over weeks to a few months may mimic infection. Several drugs used to treat connective tissue diseases may cause interstitial disease, increase susceptibility to infection, or both. This complicates differential diagnosis. Acute lupus pneumonitis and SLE-related alveolar hemorrhage are usually fulminant processes, often associated with fever. Diagnosis of these conditions always requires exclusion of infection. Rheumatoid nodules may mimic infectious and neoplastic lung diseases. Needle biopsy helps reduce the likelihood of infection or malignancy, but open lung biopsy is needed if a firm diagnosis of rheumatoid nodules is required.

The 131.1-kilobase (kb) bacteriocin production (Bac) plasmid pNP2 and the 63.6-kb lactose metabolism (Lac) plasmid pCS26, from Streptococcus lactis subsp. diacetylactis WM4, as well as pWN8, a 116.7-kb recombinant plasmid from a Lac+ transconjugant, were analyzed with restriction enzymes to determine the origin of pWN8. Plasmid pWN8 conferred a Lac+ Bac- phenotype, contained DNA derived from pCS26 and pNP2, and, like pNP2, exhibited self-transmissibility (Tra+). In cloning attempts, Bac+ transformant S. lactis KSH1 was isolated. The recombinant plasmid, pKSH1, contained three BclI fragments from pNP2. Bac- transformants which individually contained each of the three fragments were also identified. Comparison of restriction maps of pKSH1 and pNP2 revealed an 18.4-kb region common to both plasmids, involving two of the three BclI fragments. S. lactis KSH1 also exhibited greater inhibitory activity against the indicator strain S. diacetylactis 18-16 than did a strain containing the 131.1-kb Bac plasmid.