Search

Heterochromatin mostly comprises repeated sequences prone to harmful ectopic recombination during double-strand break (DSB) repair. In Drosophila cells, 'safe' homologous recombination (HR) repair of heterochromatic breaks relies on a specialized pathway that relocalizes damaged sequences away from the heterochromatin domain before strand invasion. Here we show that heterochromatic DSBs move to the nuclear periphery to continue HR repair. Relocalization depends on nuclear pores and inner nuclear membrane proteins (INMPs) that anchor repair sites to the nuclear periphery through the Smc5/6-interacting proteins STUbL/RENi. Both the initial block to HR progression inside the heterochromatin domain, and the targeting of repair sites to the nuclear periphery, rely on SUMO and SUMO E3 ligases. This study reveals a critical role for SUMOylation in the spatial and temporal regulation of HR repair in heterochromatin, and identifies the nuclear periphery as a specialized site for heterochromatin repair in a multicellular eukaryote.

Background: Although obese patients have high thrombosis rates following injury, the role of obesity in coagulation after trauma remains unknown. We hypothesized that body mass index (BMI) is independently associated with increased measures of hypercoagulability longitudinally after injury., Methods: Data were prospectively collected for 377 consecutive highest-level trauma activation patients with a BMI of 18.5 kg/m² or greater. Standard coagulation measures, citrated kaolin and functional fibrinogen thromboelastography, as well as clotting factors were measured at 0 hour to 120 hours. BMI categories were defined as normal weight (18.5-24.99 kg/m²), overweight (25-29.99 kg/m²), and obese (≥30 kg/m²)., Results: The 377 patients were mostly male (81%) and had blunt injury (61%), with a median BMI of 25.8 kg/m². Of the patients, 42% were normal weight (median BMI, 22.5 kg/m²). There were no differences in age, sex, Injury Severity Score (ISS), or base deficit between groups. There were no differences in admission international normalized ratio/partial thromboplastin time or factors II, V, VII, VIII, and X; antithrombin III; or protein C. However, obese patients had higher admission platelet counts (303 × 10⁹/L vs. 269 × 10⁹/L, p = 0.004), lower D-dimer (1.88 μg/mL vs. 4.00 μg/mL, p = 0.004), and a trend toward higher factor IX (134% vs. 119% activity, p = 0.042) compared with normal weight patients. Measured by thromboelastography, clot strength (maximum amplitude) and functional fibrinogen level (FLEV) were also higher on admission for obese patients (maximum amplitude, 65.7 mm vs. 63.4 mm, p = 0.016; FLEV, 407 mg/dL vs. 351 mg/dL, p = 0.008). In multiple linear regression, the relationship of BMI to clot strength, FLEV, and factor IX persisted through 24 hours. Similarly, the relationship of BMI and platelet count persisted through 120 hours (all p < 0.05). In multiple logistic regression, for every 5-kg/m² increase in BMI, there was an 85% increase in odds of thromboembolic complication (odds ratio, 1.85; 95% confidence interval, 1.13-3.08; p = 0.017)., Conclusion: Obese trauma patients are hypercoagulable compared with their similarly injured normal-weight counterparts, which persists longitudinally after injury. The significance of this hypercoagulability requires elucidation for guidance of anticoagulation in this at-risk group., Level of Evidence: Prognostic study, level III.

We previously demonstrated essential roles of the Fas-Fas ligand (FasL) pathway in bleomycin-induced pneumopathy in mice. T lymphocytes and natural killer cells express FasL on activation and use it as a cytotoxic effector molecule. Because interleukin (IL)-12 is known to play a critical role in cell-mediated immunity, we investigated whether anti-IL-12 antibody treatment suppresses the development of this model. The anti-IL-12 antibody treatment decreased the number of apoptotic cells and the degree of inflammation and fibrosis in lung tissue. The results of RT-PCR showed that IL-12p40, IL-12 receptor (R) beta2, interferon-gamma, tumor necrosis factor-alpha and FasL mRNAs were upregulated after bleomycin instillation. The upregulation of FasL, IL-12Rbeta2, and tumor necrosis factor-alpha mRNA expression in lung tissue was suppressed by anti-IL-12 antibody treatment. The results of enzyme-linked immunosorbent assay showed that the levels of IL-12p40, but not of IL-12p70, were increased in lung tissue after bleomycin instillation. Although the increase in IL-12Rbeta2 mRNA levels suggests that the T helper type 1 cell response may participate in lung injury, the increase in IL-12p40 supports T helper type 2 cell predominance in the fibrotic process of this model. The administration of anti-IL-12 antibody could be a novel therapy against lung injury and pulmonary fibrosis.

Caspases have been implicated in the effector process of apoptosis in several systems including the Fas-Fas ligand pathway. We previously demonstrated that excessive apoptosis of lung epithelial cells and the Fas-Fas ligand pathway were essential in the pathogenesis of bleomycin-induced pneumopathy in mice. Therefore, the purpose of this study was to investigate whether a caspase inhibitor could prevent the development of this model. The expression of caspase-1 and caspase-3 was upregulated on lung epithelial cells, alveolar macrophages, and infiltrating inflammatory cells in this model. We demonstrated that a broad-spectrum caspase inhibitor, N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone, decreased the caspase-1- and caspase-3-like activity, the number of apoptotic cells, the pathological grade of lung inflammation and fibrosis, and the hydroxyproline content in lung tissues in this model. We conclude that caspase inhibitors could be a new therapeutic approach against lung injury and pulmonary fibrosis.

Background: KL-6, and surfactant protein A (SP-A) and surfactant protein D (SP-D) derived from alveolar type II cells and/or bronchiolar epithelial cells have been reported to be useful markers for interstitial lung diseases., Objective: The aim of this study was to measure the levels of these molecules in bronchoalveolar lavage fluid (BALF) from patients with pulmonary sarcoidosis to investigate their relationship with other markers of inflammatory activity., Methods: We measured KL-6, SP-A and SP-D levels in BALF from patients with pulmonary sarcoidosis using an ELISA., Results: KL-6 and SP-D, but not SP-A levels were significantly increased in pulmonary sarcoidosis compared with controls. KL-6, SP-A and SP-D levels were significantly correlated with each other. KL-6 and SP-D levels were relatively and significantly correlated with the percentage of lymphocytes in BALF. KL-6, SP-D, but not SP-A levels were significantly correlated with the concentration of albumin in BALF. There was no significant correlation between KL-6, SP-A, or SP-D levels and chest X-ray findings, angiotensin-converting enzyme levels, or CD4/CD8 ratio in BALF., Conclusions: We conclude that KL-6 and SP-D levels in BALF were increased in pulmonary sarcoidosis. Since these markers are specifically derived from epithelial cells, it is considered that KL-6 and SP-D levels are reflecting damage or release of these markers from epithelial cells due to the inflammatory response., (Copyright 2001 S. Karger AG, Basel)

LPS (lipopolysaccharide) is one of the major factors that induce acute lung injury. Recently, it was reported that LPS induced disseminated endothelial apoptosis, preceding nonendothelial tissue damage. Caspases play important roles in apoptosis, including tumor necrosis factor-alpha-induced apoptosis, in several systems. We therefore investigated whether the injection of a caspase inhibitor prevents LPS-induced apoptosis and acute lung injury in mice. LPS (30 mg/kg) was administered intravenously to Institute for Cancer Research mice. Electron microscopic findings demonstrated characteristic features of apoptosis in endothelial cells and alveolar epithelial cells. The caspase-3 activity and the number of terminal dUTP nick-end labeling-positive cells in lung tissues were significantly increased after LPS administration. Benzyloxycarbonil-Val-Ala-Asp fluoromethylketone (Z-VAD.fmk), which is a broad-spectrum caspase inhibitor, was injected before and after the administration of LPS. The injection of Z-VAD.fmk suppressed the caspase-3 activity in lung tissues, and significantly decreased the number of terminal dUTP nick-end labeling-positive cells. Furthermore, the survival rate of mice was prolonged significantly by the injection of Z-VAD.fmk. These results indicate that apoptosis may play an important role in acute lung injury, and thus that inhibition of caspase activity may constitute a new therapeutic approach for treatment of this disease.

Up-regulation of Fas and Fas ligand and excessive apoptosis of bronchiolar and alveolar epithelial cells were identified in bleomycin-induced pulmonary fibrosis in mice. This study hypothesized that apoptosis-regulatory genes other than Fas-Fas ligand, such as p53, p21 (Waf1/Cip1), bcl-2, bcl-x, and bax, may also participate in epithelial cell apoptosis in this model. The expression of these genes was assessed by reverse transcription polymerase chain reaction (RT-PCR), RT in situ PCR, or immunohistochemistry. The expression of p53 and p21 mRNA was concurrently up-regulated in the alveolar epithelial cells at 1 h to 7 days after intratracheal instillation of bleomycin. The expression of bcl-2 mRNA was weakly up-regulated at 1 h to 14 days, while the expression level of bcl-2 protein was not changed. The expression of bcl-x(L) and bax mRNA was strongly up-regulated at 1 h to 7 days. The expression of bcl-x protein was up-regulated in lymphocytes and macrophages, whereas bax protein was up-regulated in both epithelial and inflammatory cells. It is concluded that epithelial cell apoptosis in this model may also be induced by the up-regulation of p53 and bax and by the imbalance between apoptosis-inducible and -inhibitory genes, in addition to the up-regulation of the Fas-Fas ligand pathway., (Copyright 2000 John Wiley & Sons, Ltd.)

Epithelial cell injury is the common manifestation of lung injury. Contributing to such injury of epithelial cells is apoptosis. Although apoptosis is part of the normal process of epithelial renewal, in excess it is pathologic. We previously demonstrated the excessive apoptosis of lung epithelial cells and the upregulation of Fas and Fas ligand (FasL) in fibrosing lung diseases. We also showed that inhalation of anti-Fas antibody induced lung injury and fibrosis in mice. Interleukin (IL)-8 is one of the most important cytokines in the pathophysiology of acute lung injury and pulmonary fibrosis. In this study we investigated whether Fas ligation induces IL-8 secretion in addition to apoptosis in bronchiolar epithelial cells in vitro. Bronchiolar epithelial cells underwent apoptosis and also secreted IL-8 in response to tumor necrosis factor (TNF)-alpha or Fas ligation. New gene expression and protein synthesis were not necessary for Fas ligation- and TNF-alpha- mediated apoptosis, but were necessary for IL-8 secretion. We further found that Fas ligation induced activation of nuclear factor-kappa B. We conclude that the Fas/FasL pathway not only mediates apoptosis but also plays a proinflammatory role, and that stimulation of the Fas/FasL pathway in bronchiolar epithelial cells leads to IL-8 production, which may amplify the inflammatory cascade in lung injury and pulmonary fibrosis.

The Fas ligand is predominantly expressed in activated T lymphocytes and is one of the major effector molecules of cytotoxic T lymphocytes and natural killer cells. Previously, we found excessive apoptosis of epithelial cells and infiltrating lymphocytes expressing Fas ligand mRNA in the lung tissue of bleomycin-induced pulmonary fibrosis in mice. Here we demonstrated that the administration of a soluble form of Fas antigen or anti-Fas ligand antibody prevented the development of this model and that lpr and gld mice were resistant against the induction of pneumopathy. These results suggest that the Fas-Fas ligand pathway plays an essential role in the development of pulmonary fibrosis and that preventing this pathway could have therapeutic value in lung injury and fibrosis.

Background: We have previously reported that the inhalation of anti-Fas antibody induced pulmonary fibrosis in mice. To induce an effective immune response, antigen-presenting cells have to not only present antigenic peptide with MHC molecules to T lymphocytes, but also express B7 costimulating molecules. The purpose of this study is to investigate whether B7 family costimulating molecules and interleukin-12 (IL-12), which primarily promote cellular immunity, are associated with anti-Fas antibody-induced pulmonary fibrosis., Methods: We examined the expression of B7-1, B7-2, and IL-12 using the revese transcription-polymerase chain reaction (RT-PCR), RT-in situ PCR, and immunohistochemistry., Results: We observed the upregulation of B7-1, B7-2, and IL-12 p40 mRNA after anti-Fas antibody inhalation. B7-2 and IL-12 p40 mRNA appeared to be expressed in mononuclear cells, while B7-1 mRNA and protein were expressed in bronchiolar epithelial cells as well as macrophages., Conclusion: These findings indicate that the T-cell-mediated immune response in this model involved the upregulation of B7-1, B7-2, and IL-12, and that the aberrant expression of B7-1 in bronchiolar epithelial cells may induce autoreactive T cell proliferation against themselves.

Background: Alveolar macrophages (AM) of sarcoidosis have an enhanced capacity to mediate antigen-induced T lymphocyte proliferation. To induce an effective immune response, antigen-presenting cells have to not only present antigenic peptide with MHC molecules to T lymphocytes, but also express B7 costimulating molecules., Objective: The purpose of this study was to investigate the expression of B7 and MHC molecules in lung tissues from patients with sarcoidosis., Methods: We performed immunohistochemistry for B7-1, B7-2 and MHC class II antigens using transbronchial lung biopsy specimens obtained from patients with sarcoidosis and normal lung parenchyma obtained by lobectomy for solitary pulmonary nodule as controls., Results: B7-1, B7-2 and MHC class II antigen were expressed in epithelioid cells in granulomas in 14 (93.3%), 2 (13.3%) and 9 (60.0%) of 15 patients with sarcoidosis, respectively. These were also expressed in AM in 14 (93. 3%), 5 (33.3%) and 12 (80.0%) of 15 patients with sarcoidosis, respectively. The positivity of B7-1 was significantly higher than that of B7-2 in both epithelioid cells and AM in sarcoidosis (p < 0. 01). Positive signals for B7-1, B7-2 and MHC class II antigen were also found in AM in 9 (90%), 8 (80%) and 8 (80%) of 15 of controls, respectively. However, the intensity of positive signals for B7-1, but not B7-2 or MHC class II antigen in AM was significantly increased in sarcoidosis compared to controls (p < 0.05)., Conclusions: These results suggested that epithelioid cells in granulomas and AM from patients with sarcoidosis had the capability to act as accessory cells and that the accessory function of these cells was shifted to B7-1 rather than B7-2 in sarcoidosis.

Pulmonary fibrosis begins with alveolitis, which progresses to destruction of lung tissue and excess collagen deposition. This process could be the result of DNA damage and a form of apoptosis. Therefore, we hypothesized that Fas ligand (FasL), which induces apoptosis in cells expressing Fas antigen (Fas), is associated with pulmonary fibrosis. We examined frozen lung tissues from seven patients with idiopathic pulmonary fibrosis (IPF), and bronchoalveolar lavage fluid (BALF) cells from 19 patients with IPF and from 17 patients with interstitial pneumonia associated with collagen vascular diseases (CVD-IP). We used five frozen lungs with normal lung parenchyma and BALF cells from 10 patients with solitary pulmonary nodule as controls. Reverse transcription-polymerase chain reaction (RT-PCR) showed that FasL messenger RNA (mRNA) was expressed in BALF cells from all patients with IPF and from 15 of 16 patients with CVD-IP. FasL mRNA was not detected in BALF cells except in one of 10 controls. RT in situ PCR detected FasL mRNA in inflammatory cells in BALF from patients with IPF. Immunohistochemistry detected FasL protein in infiltrating lymphocytes and granulocytes in all of seven frozen lung tissues of IPF, but in none of five control lung tissues. Additionally, the expression of Fas appeared to be upregulated in bronchiolar and alveolar epithelial cells in IPF compared with normal lung parenchyma by immunohistochemistry. We conclude that Fas and FasL were upregulated in fibrosing lung diseases and may associate with DNA damage or apoptosis of bronchiolar and alveolar epithelial cells in this disorder.

Therapeutic efficacy and the treatment days for cure of imipenem/cilastatin sodium (IPM/CS) in treatment of pulmonary infections were prospectively determined in comparison with those of beta-lactams other than carbapenems mainly ceftazidime (CAZ) or sulbactam/cefoperazone (SBT/CPZ). The overall response rate was 84.9% (62/73) in the IPM/CS group and 74.7% (56/75) in the beta-lactam group, the difference not being significant. In the subjects having underlying respiratory diseases, the response rate was 91.1% (41/45) and 73.9% (34/46) in the IPM/CS and beta-lactam groups, respectively. In patients with infections secondary to chronic respiratory disease, the rate was 91.2% (31/34) in the former group and 66.7% (24/36) in the latter group, respectively. The differences were significant for both stratified analyses. The treatment days for cure judged by the attending physician were 12.9 +/- 0.6 days in the IPM/CS group, and 14.5 +/- 0.7 days in the beta-lactam group. The difference was not, however, significant. In patients with mild to moderate infections, the treatment days for cure was 12.0 +/- 0.6 days (n = 64) in the IPM/CS group and 14.3 +/- 0.7 days (n = 70) in the beta-lactam group. In patients with underlying respiratory disease, the treatment days for cure were 11.8 +/- 0.7 days (n = 45) and 14.7 +/- 0.9 days (n = 46) in the IPM/CS and beta-lactam groups, respectively. In patients with infections secondary to chronic respiratory disease, the days were 11.1 +/- 0.7 days (n = 34) and 14.7 +/- 1.1 days (n = 36), respectively. Thus, IPM/CS therapy significantly reduced the number of treatment days until cure. There was, however, no significant difference between the two therapy groups in treatment of the patients with severe infections, those without underlying respiratory disease, or those with pneumonia and/or lung abscess. The treatment days for cure were also assessed by the members of review committee taking into consideration of body temperature, leukocyte count, and C-reactive protein. As the result, it was 6.9 +/- 0.5 days in the IPM/ CS and 10.3 +/- 0.7 days in the beta-lactam groups; respectively, and the difference was significant. Time (days) until cure was also compared between the two groups using survival time analysis, confirming a more rapid response in the IPM/CS group. Although IPM/CS therapy was associated with a shorter response time as assessed by both the attending physicians and the review committee, there were considerable differences between the results of these judgements. Thus, the duration of treatment with injectable antibiotics requires reevaluation in the future. No significant differences were observed between the groups with respect to parameters indicating side effects and laboratory abnormalities. There were no severe symptoms or laboratory findings, and symptoms and changes in laboratory values, if any resolved during the course of therapy or after the withdrawal of treatment. In conclusion, IPM/CS seems to be very useful as first-line therapy for respiratory tract infections and for shortening the duration of treatment.

Background: Studies have shown the importance of apoptosis in vascular injury in vitro. We postulated that apoptosis of the endothelium contributes to vascular injury in vivo and may be involved in acute lung injury., Methods: To test this hypothesis, we investigated the incidence of endothelial cell apoptosis in acute lung injury induced in mice by the administration of lipopolysaccharide (LPS). Male ICR mice were administered LPS (20 mg/kg body weight) intravenously and sacrificed at specified times thereafter., Results: Histologic findings were consistent with acute lung injury which increased with time from 3 to 48 h after injection. Electrophoretic analysis of DNA that was extracted from lung tissue and 3'-end-labeled with digoxigenin demonstrated a fragmentation of DNA starting at 6 h. In situ terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end-labeling (TUNEL) demonstrated DNA strand breaks in the endothelial cells. TUNEL also revealed DNA strand breaks in bronchial and alveolar epithelial cells as well as inflammatory cells in the interstitium. These TUNEL-positive cells appeared 6 h after injection. Electron-microscopic examination of the endothelium strongly suggested the morphological characteristics of apoptosis., Conclusion: Apoptosis was induced by LPS administration in endothelial cells in vivo. A role for such apoptosis is suggested in acute lung injury.

Background: The bleomycin-induced pneumopathy involves a T cell-mediated immune response. T cell activation requires both antigen/MHC recognition and costimulatory signals. The CD28 receptor on T cells with its ligand B7 represents one of the most important examples of this costimulation. Interleukin 12 (IL-12) has a strong synergistic effect with the B7-1/CD28 interaction on inducing proliferation and cytokine production in T cells., Methods: In this study, we investigated the expression of B7-1, B7-2, and IL-12 in bleomycin-induced pneumopathy in mice using reverse transcription polymerase chain reaction (RT-PCR), RT in situ PCR, and immunohistochemistry., Results: We observed concurrent upregulation of B7-1, B7-2, and IL-12p40 mRNA in the lung tissues at 1 h to 7 days after bleomycin instillation into the trachea. B7-1 mRNA and protein were found in bronchiolar epithelial cells as well as macrophages, B7-2 and IL-12p40 mRNA appeared to be expressed in mononuclear cells., Conclusions: These findings indicate that T cell-mediated immune response in this model involves the upregulation of B7-1, B7-2, and IL-12p40 mRNA, and also demonstrate the aberrant expression of B7-1 in bronchiolar epithelial cells.

Fas antigen is a cell surface protein that mediates apoptosis, and it is expressed in various cells and tissues. Fas ligand binds to its receptor Fas, thus inducing apoptosis of Fas-bearing cells. Malfunction of the Fas-Fas ligand system causes lymphoproliferative disorders and autoimmune diseases, whereas its exacerbation may cause tissue destruction. We hypothesize that excessive apoptosis mediated by Fas-Fas ligand interaction may damage alveolar epithelial cells and result in pulmonary fibrosis. Mice were allowed to inhale repeatedly an aerosolized anti-Fas antibody for 14 days. The nuclei of bronchial and alveolar epithelial cells were positively stained by in situ DNA nick end labeling. Electron microscopy demonstrated apoptotic changes in bronchial and alveolar epithelial cells. Histologic findings and hydroxyproline content showed the development of pulmonary fibrosis, which was dependent on the dose of anti-Fas antibody. The repeated inhalation of control antibody (isotype-matched control hamster IgG) did not induce apoptosis of epithelial cells or pulmonary fibrosis. The expression of TGF-beta mRNA was upregulated from day 7 to day 28 in lung tissues of anti-Fas antibody-treated mice but not in those of control mice. In this report, we present the evidence that repeated inhalation of anti-Fas antibody mimicking Fas-Fas ligand crosslinking induces excessive apoptosis and inflammation, which results in pulmonary fibrosis in mice.

Disseminated intravascular coagulation (DIC) is a very rare complication of pulmonary tuberculosis. We herein describe a case of cavitary tuberculosis complicated with DIC. Rifampin was considered to deteriorate the clinical course of DIC in this case.

The tumor suppresser p53 is a cell cycle checkpoint protein that contributes to the preservation of genetic stability by mediating either a G1 arrest or apoptosis in response to DNA damage. p53 causes growth arrest through transcriptional activation of the cyclin-dependent kinase inhibitor p21. During p53-mediated suppression of cell proliferation, p21 is important for coordinating cell cycle progression, DNA replication, and repair of damaged DNA. The purpose of this study is to investigate the expression of p53 and p21 mRNA in association with DNA damage and normal repair in acute immune complex alveolitis in mice. Male ICR mice were injected intravenously with IgG antibodies against oval albumin, aerosolized with oval albumin solution, and killed at 4, 6, 12, 24, and 48 hours and 1 week after aerosolization. We assessed the expression of p53 and p21 mRNA by reverse transcriptase (RT)-PCR and by RT in situ PCR. We also assessed DNA damage by terminal deoxynucleotidyl transferase mediated biotin-dUTP nick-end-labeling (TUNEL) and by gel electrophoresis of DNA extracted from lung tissues. The results of RT-PCR and RT in situ PCR showed that p53 and p21 mRNA were concurrently up-regulated at 4 to 48 hours after aerosolization in alveolar epithelial cells. Bronchial and alveolar epithelial cells were positively stained by TUNEL in this period but not at 1 week after aerosolization or in control mice. The result of electrophoretic analysis of DNA was compatible with that of TUNEL. These studies suggest that the responses of p53 and p21 mRNA are associated with physiologic processes of DNA damage and repair in acute immune complex alveolitis in mice.

A fully automatic and continuous cell culture system based on roller bottles is described in this paper. The system includes a culture rack storage station for storing a large number of roller bottles filled with culture medium and inoculated with mammalian cells, mass-handling facility for extracting completed cultures from the roller bottles, and replacing the culture medium. The various component units of the system were controlled either by a general-purpose programmable logic controller or a dedicated controller. The system provided four subsequent operation modes: cell inoculation, medium change, harvesting, and medium change. The operator could easily select and change the appropriate mode from outside of the aseptic area. The development of the system made large-scale production of mammalian cells, and manufacturing and stabilization of high quality products such as erythropoietin possible under total aseptic control, and opened up the door for industrial production of physiologically active substances as pharmaceutical drugs by mammalian cell culture.

Group C adenovirus is latent in human tissues and can malignantly transform cells. The purpose of this study was to investigate the association between this virus and lung cancer. We investigated latent adenoviral infection using the nested polymerase chain reaction and in situ hybridization in transbronchial biopsy specimens from patients with small-cell lung cancer and non-small-cell lung cancer. The polymerase chain reaction was performed on DNA extracts with two sets of primers directed at a 261-base-pair target sequence of the E1A region of the adenoviral genome. In situ hybridization was performed on histological sections using DNA representing the entire adenovirus type 5 genome. E1A target DNA was present in 11 (31%) of 35 cases of small-cell lung cancer but in none of the 40 cases of non-small-cell lung cancer (P < 0.01). Of the 11 cases found positive by PCR, 8 were positive for adenovirus DNA by in situ hybridization. Adenovirus was prominent in tumor cells in 5 of the 8 cases, and in normal epithelial cells in the 3 remaining cases. Adenovirus DNA was not detected by in situ hybridization in specimens in which E1A DNA was not detected by the polymerase chain reaction. Small-cell lung cancer has mutations or deletions in the p53 and retinoblastoma genes more frequently than are found in non-small-cell lung cancer. Therefore, we speculate that adenovirus infection might participate in the pathogenesis of SCLC by producing mutation in these genes, rather than by inhibiting the function of these proteins.

A 30-year-old woman with systemic lupus erythematosus was admitted to our hospital because of a slight fever and diffuse interstitial shadows on a chest X-ray film. She had taken prednisolone (60 mg per day) at another hospital for six weeks. At the time of admission to our hospital, she had been treated with antituberculosis drugs (streptomycin, isoniazid, and rifampicin) for two weeks because of suspected miliary tuberculosis. Chest radiography on admission revealed diffuse nodular and micronodular shadows in the middle and lower lung fields on both sides. Examination of transbronchial lung biopsy specimens revealed intranuclear viral inclusion bodies in infected alveolar epithelial cells, which suggested the diagnosis of cytomegalovirus infection. The elevation of serum IgM antibody to cytomegalovirus and positive results of in situ hybridization for cytomegalovirus DNA supported this diagnosis. The symptoms and radiographic abnormalities resolved completely without ganciclovir. Although we cannot exclude the possibility that the antituberculosis drugs caused the resolution of the cytomegalovirus pneumonia, it appears most probable that the cytomegalovirus pneumonia resolved spontaneously.

Aspergillus fumigatus is an apportunistic nosocomial pathogen in immunosuppressed patients or in the lesion where the local defense mechanism was impaired. Patients with pneumoconiosis are known to be susceptible to chronic necrotizing pulmonary aspergillosis. Therefore, we hypothesized that A. fumigatus might be prevalent in sputum from patients with coal workers' pneumoconiosis, and also that asthmatic symptoms in patients with coal workers' pneumoconiosis may be associated with the presence of A. fumigatus. We tested for A. fumigatus in the sputum from patients with coal workers' pneumoconiosis by nested polymerase chain reaction amplification of the Asp fI gene. Sequences specific for this gene were detectable in 5 of 11 (45.5%) patients with coal workers' pneumoconiosis with asthmatic symptoms (group A), 5 of 10 (50.0%) patients with coal workers' pneumoconiosis without asthmatic symptoms (group B) and only 1 of 9 (11.1%) patients with chronic airflow obstruction without pneumoconiosis (group C). The frequency of the Asp fI gene detection was significantly higher in groups A and B than in group C (p < 0.05). The prevalence of A. fumigatus was not associated with asthmatic symptoms. These results demonstrated that A. fumigatus was prevalent in patients with coal workers' pneumoconiosis. We speculate that colonization with A. fumigatus may be associated with this disease.

Bleomycin-induced cytotoxicity is believed to be caused by single- and double-strand DNA breaks. To examine the effect of bleomycin on DNA strand breaks and the role of these breaks in bleomycin induced pulmonary fibrosis in mice, we analyzed DNA strand breaks in situ by TdT-mediated dUTP-biotin nick end labeling (TUNEL), previously described by Gavrieli et al. The nuclei of bronchiolar epithelial cells were strongly stained 1 hr to 12 hr after bleomycin administration, and after that period DNA damage was repaired. Nuclei of alveolar epithelial cells showed positive signals correlated with progression of fibrosis. Although corticosteroids did not block the early DNA damage in bronchiolar epithelial cells, they did inhibit later damage to alveolar epithelial cells and fibrosis. We speculate that the DNA damage in alveolar epithelial cells and the progression of fibrosis in later stages are associated with inflammatory cytokines. These findings show the location and the time course of the DNA damage in bleomycin-induced pneumonitis in mice, and they indicate that the prolongation of DNA damage in alveolar epithelial cells is closely related to fibrinogenesis.

In order to investigate immunological abnormalities induced by polychlorinated biphenyls and polychlorinated dibenzofurans, we have performed bronchoalveolar lavage in the rats given polychlorinated biphenyls and polychlorinated dibenzofurans. We have administrated 5.0 mg of polychlorinated biphenyls or 0.5 mg of polychlorinated dibenzofurans to Sprague-Dawley rats intraperitoneally. Four weeks after the administration, mild necrosis of bronchiolar Clara cells and mild edema associated with chronic inflammatory infiltration in the alveoli were seen in both groups. In the peripheral blood, percentage of T-lymphocyte, helper T-cell and suppressor T-cell decreased significantly both in polychlorinated biphenyls and polychlorinated dibenzofurans given rats. On the other hand, in the bronchoalveolar lavage fluid, percentage of T-cell increased only in polychlorinated dibenzofurans given rats and percentage of suppressor T-cell increased in both groups. O2- release by alveolar macrophage increased significantly both when stimulated with wheat germ lectin and with phorbol myristate acetate. These results indicate that immunological alternation may be different between peripheral blood and respiratory system as one of the target organs of these chemicals. Further examination is needed for the analysis of immunological abnormalities in the target organs of polychlorinated biphenyls and polychlorinated dibenzofurans poisoning.