H3K9 methyltransferases and demethylases control lung tumor-propagating cells and lung cancer progression.

Epigenetic regulators are attractive anticancer targets, but the promise of therapeutic strategies inhibiting some of these factors has not been proven in vivo or taken into account tumor cell heterogeneity. Here we show that the histone methyltransferase G9a, reported to be a therapeutic target in many cancers, is a suppressor of aggressive lung tumor-propagating cells (TPCs). Inhibition of G9a drives lung adenocarcinoma cells towards the TPC phenotype by de-repressing genes which regulate the extracellular matrix. Depletion of G9a during tumorigenesis enriches tumors in TPCs and accelerates disease progression metastasis. Depleting histone demethylases represses G9a-regulated genes and TPC phenotypes. Demethylase inhibition impairs lung adenocarcinoma progression in vivo. Therefore, inhibition of G9a is dangerous in certain cancer contexts, and targeting the histone demethylases is a more suitable approach for lung cancer treatment. Understanding cellular context and specific tumor populations is critical when targeting epigenetic regulators in cancer for future therapeutic development.

Multiple intra-hospital transports during relocation to a new critical care unit.

OBJECTIVE: Intra-hospital transport (IHT) of critically ill patients is associated with morbidity and mortality. Mass transfer of patients, as happens with unit relocation, is poorly described. We outline the process and adverse events associated with the relocation of a critical care unit. DESIGN: Extensive planning of the relocation targeted patient and equipment transfer, reduction in clinical pressure prior to the event and patient care during the relocation phase. SETTING: The setting was a 30-bed, tertiary referral, combined medical and surgical critical care unit, located in a 570-bed hospital that serves as the national referral centre for cardiothoracic surgery and spinal injuries. PARTICIPANTS: All stakeholders relevant to the critical care unit relocation were involved, including nursing and medical staff, porters, information technology services, laboratory staff, project development managers, pharmacy staff and building contractors. MAIN OUTCOME MEASURES: Mortality at discharge from critical care unit and discharge from hospital were the main outcome measures. A wide range of adverse events were prospectively recorded, as were transfer times. RESULTS: Twenty-one patients underwent IHT, with a median transfer time of 10 min. Two transfers were complicated by equipment failure and three patients experienced an episode of hypotension requiring intervention. There were no cases of central venous or arterial catheter or endotracheal tube dislodgement, and hospital mortality at 30 days was 14%. CONCLUSION: Although IHT is associated with morbidity and mortality, careful logistical planning allows for efficient transfer with low complication rates.

Fractured closed suction catheter: an unusual cause of endobronchial obstruction in a ventilated patient.

BACKGROUND: A 32-year-old HIV-positive man required ventilation for seizures secondary to viral encephalitis. He had a prolonged care unit stay and had percutaneous tracheostomy performed on day 14 of his admission. He subsequently developed persistent right basal infiltrates and atelectasis on chest radiographs that were slow to respond to antibiotic treatment. Fiberoptic bronchoscopy revealed the cause of his infiltrates to be a 14-cm tip section of closed suction catheter tubing that had presumably fractured during suctioning and became lodged in his trachea and right main bronchus. LEARNING POINT: Foreign body aspiration should be considered in the differential diagnosis of persisting lung infiltrates or atelectasis in all patients. CONCLUSION: This case describes a rare cause of endobronchial obstruction in a ventilated patient. Medical staff requires education about the importance of ensuring that suction catheters and other airway adjuncts are intact following use to prevent possible airway foreign bodies.

Plasminogen activator inhibitor type 2 (PAI-2) is present in normal human conjunctiva.

The purpose was to characterize plasminogen activator inhibitor type 2 (PAI-2) expression in normal human conjunctiva in vivo and in vitro. PAI-2 antigen was assayed by immunostaining and immunoblotting of extracts from normal human conjunctival epithelial lysates and conditioned media (CM) of cultured human conjunctival keratinocytes. Immunostaining of normal human conjunctival epithelia revealed that PAI-2 was found consistently in the superficial keratinocytes and, in some biopsies, also in the lower keratinocyte layers. In all cases, PAI-2 was concentrated around the cell periphery. In extracts of conjunctival epithelia and cultured conjunctival keratinocytes, PAI-2 had an apparent molecular weight of 45 kDa, consistent with the non-glycosylated form. The majority of PAI-2, approximately 90%, was cell associated, however, a small percentage of PAI-2 was released into the CM in a linear manner with time. PAI-2 in the conditioned medium had a higher molecular weight, consistent with a glycosylated form. Conjunctival PAI-2 was active, as shown by its ability to complex with a target enzyme, urokinase plasminogen activator (uPA). Although PAI-2 was detectable both in monolayer (i.e., relatively undifferentiated) conjunctival keratinocyte cultures as well as in stratified (i.e., more differentiated) cultures, steady state levels of PAI-2 were greater in the latter. PAI-2 is constitutively expressed by normal human conjunctival epithelial cells. The expression of PAI-2 throughout all epithelial layers in some biopsies of conjunctiva in vivo contrasts with the previously established distribution of PAI-2 in corneal epithelia, where it is present exclusively in the most superficial (i.e. most highly differentiated) cells. The role of PAI-2 in either tissue is unclear. However, we speculate that its distinct distribution in conjunctival versus corneal epithelia underscores inherent differences between these tissues, and may reflect specific functions of this proteinase inhibitor in both conjunctival and corneal epithelial cells.

Subcutaneous tissue oxygen tension after coronary revascularisation with and without cardiopulmonary bypass.

Directly measured subcutaneous tissue oxygen tension reflects the adequacy of regional tissue oxygenation and influences wound infection and healing. We tested the hypothesis that off-pump coronary artery bypass would increase subcutaneous tissue oxygen tension by minimizing cardiopulmonary bypass-induced systemic inflammation. Ten consecutive patients scheduled for off-pump coronary artery bypass were compared with 10 undergoing conventional cardiopulmonary bypass. All patients had a tissue oxygen sensor implanted longitudinally into the subcutaneous tissue of the leg in the saphenous vein harvest wound. Data were collected from closure of the saphenous vein wound for 20 h postoperatively. Although more off-pump patients had only one coronary artery grafted, postoperative subcutaneous tissue oxygen tension was significantly higher in off-pump patients throughout the 20-h study. Absolute mean (SD) differences ranged from 2.3 kPa in the first 2 h [14.4 (2.3) vs. 12.1 (2.4) kPa in off-pump and cardiopulmonary bypass, respectively, p = 0.04] to 4.6 kPa at 8-10 h [14.0 (3.5) vs. 9.3 (2.7) kPa, p = 0.007]. In contrast, there were no significant differences in arterial oxygen tension values over this period. Mean arterial pressure and haemoglobin were transiently higher in off-pump patients at 8 h only. We conclude that postoperative subcutaneous tissue oxygen tension was higher for 20 h after off-pump compared with conventional cardiopulmonary bypass.

Sodium dodecyl sulfate induces plasminogen activator inhibitor type 2 expression in epidermal keratinocytes in vivo and in vitro.

The detergent sodium dodecyl sulfate is a well-known inducer of irritant contact dermatitis. In this study we show that sodium dodecyl sulfate induces the serine proteinase inhibitor, plasminogen activator inhibitor type 2, in epidermal keratinocytes. The enhancement in plasminogen activator inhibitor type 2 mRNA and antigen is observed both when sodium dodecyl sulfate is applied topically to normal human skin as well as when it is added to the growth medium of cultured human keratinocytes. In vitro, plasminogen activator inhibitor type 2 mRNA is increased within 4-8 h after addition of the detergent, and the increase in plasminogen activator inhibitor type 2 antigen occurs slightly later. The enhancing effect of sodium dodecyl sulfate on plasminogen activator inhibitor type 2 is not related to nonspecific cell lysis nor is it secondary to induction of tumor necrosis factor alpha. Similarities between our in vitro and in vivo findings lead us to hypothesize that sodium dodecyl sulfate may exert its effect on epidermal plasminogen activator inhibitor type 2 via interaction with the keratinocyte.

Low voltage electrical stimulation of lamb carcasses: effects on meat quality.

The effects of an early post mortem low voltage electrical stimulation (28 V, 60 Hz) on biochemical changes and on final tenderness in muscles Longissimus thoracis et lumborum and Semimembranosus from lamb carcasses were studied. It was shown that electrical stimulation accelerated the glycolytic process resulting in a significant fall in pH during the first 6 h post mortem in both muscles examined and in a significant reduction in adenosine triphosphate (ATP) content in muscle Longissimus thoracis et lumborum. The effect of electrical stimulation on tenderness was recorded by measuring shear force values 2 and 7 days post mortem. Tenderness was significantly improved by electrical stimulation for the Longissimus thoracis et lumborum both at 2 and at 7 days post mortem, while for Semimembranosus electrical stimulation significantly increased tenderness just at 7 days post mortem.

A simple method for closure of tracheocutaneous fistula in children.

OBJECTIVE: To review the results of a simple technique of closure of persistent tracheocutaneous fistula (TCF) in children. DESIGN: Retrospective case series. SETTING: Tertiary pediatric otolaryngology referral center. PATIENTS: Children (age, < 18 years) who underwent repair of TCF from July 1, 1991, to August 31, 1996. INTERVENTIONS: Surgical closure of persistent TCF using multilayered closure of de-epithelialized local tissue. Tracheal dissection was not performed. A thermal hemostatic scalpel was used in some cases to assist in de-epithelialization and provide hemostasis without electrocautery near the airway. MAIN OUTCOME MEASURES: Success of closure and number and types of complications. RESULTS: Nine procedures were performed in 8 children. Seven (88%) of 8 primary procedures were successful, but early recurrent TCF developed in 1 patient. Revision surgery using an identical surgical technique, but maintaining endotracheal intubation for 48 hours, was successful in this patient. No complications occurred. CONCLUSIONS: This procedure is a simple, reliable method for closure of TCF in children.

Infectious complications of human T cell leukemia/lymphoma virus type I infection.

Infection with human T cell leukemia/lymphoma virus type I (HTLV-I) has been etiologically associated with two diseases: adult T cell leukemia and HTLV-I-associated myelopathy/tropical spastic paraparesis. Increasing evidence suggests that HTLV-I infection may be associated with immunosuppression and, as a consequence, affect the risk and expression of several other infectious diseases, of which the best studied are strongyloidiasis, tuberculosis, and leprosy. In strongyloidiasis, coinfection with HTLV-I appears to result in a higher rate of chronic carriage, an increased parasite load, and a risk of more severe infection. In tuberculosis, a decrease in delayed-type hypersensitivity to Mycobacterium tuberculosis has been established, but whether this decrease is clinically significant has yet to be determined. In leprosy, an increased risk of disease is suggested, but the published studies are all too poorly controlled to draw definite conclusions.

Airway foreign bodies.

The removal of airway foreign bodies can be challenging even for the most experienced endoscopist. A familiarity with and working knowledge of older time-tested techniques and instrumentation as well as of the newer rigid and flexible fiberoptic equipment is essential for all who desire to accept these challenging situations. Each instrument has inherent advantages, disadvantages, and limitations in certain situations. Occasionally, a foreign body may be removed more safely through open surgical procedures. A knowledge of the lessons learned and techniques developed by pioneering endoscopists coupled with continuing practice of different endoscopy techniques with a variety of instrumentation will prepare the endoscopist to handle unusual foreign body dilemmas with greater skill and safety.

Skin testing with Mycobacterium avium sensitin to identify infection with M. avium complex in patients with cystic fibrosis.

We sought to determine if patients with cystic fibrosis and sputum cultures positive for Mycobacterium avium complex (MAC) have delayed-type hypersensitivity to an M. avium sensitin. Seventeen (33%) of 51 selected patients had MAC isolated from at least one sputum culture. Skin tests with purified protein derivative and M. avium sensitin demonstrated that five (10%) of 51 patients were anergic, and anergy was correlated with use of systemic steroids. Sixteen (35%) of 46 nonanergic patients had M. avium-dominant skin test reactions. Twelve (75%) of these 16 patients with cultures positive for MAC had M. avium-dominant skin tests; the specificity of skin testing was 87%. These data suggest that most patients with cystic fibrosis and sputum cultures positive for MAC have infection rather than colonization with MAC. Skin testing with M. avium sensitin is a sensitive and specific method for screening these infections.

Persistent activation of cAMP-dependent protein kinase by regulated proteolysis suggests a neuron-specific function of the ubiquitin system in Aplysia.

In response to the facilitating neurotransmitter serotonin (5-HT), the cAMP-dependent protein kinase (PKA) acquires a special mnemonic characteristic in Aplysia sensory neurons. PKA becomes persistently activated at basal cAMP concentrations owing to a decreased regulatory (R) to catalytic (C) subunit ratio. We previously implicated ubiquitin-mediated proteolysis in this selective loss of R. Here we show that ubiquitin (Ub), Ub-conjugates and proteasomes are present in cell bodies, axon, neuropil and nerve terminals of Aplysia neurons. Because R subunits are not decreased in muscle exposed to 5-HT, comparison of the two tissues provides a tractable approach to determine how the Ub pathway is regulated. We compared the structure of M1, the muscle-specific R isoform, to that of N4, a major neuronal R isoform, to rule out the possibility that the differences in their stability result from differences in structure. We present evidence that N4 and M1 are encoded by identical transcripts; they also behave similarly as protein substrates for the Ub pathway in extracts of the two tissues. Nervous tissue contains 20-times more free Ub, but we present evidence that the susceptibility of R subunits to degradation in neurons relative to muscle results from the greater capacity of neurons to degrade ubiquitinated proteins through the proteasome. Thus, factors that regulate the activity of proteasomes could underlie the enhanced degradation of R subunits in long-term sensitization.

Clinical experience with an endobronchial implant.

PURPOSE: To report clinical experience with an implantable capsule for treating endobronchial carcinoma by means of bronchoscopic insertion and retrieval. MATERIALS AND METHODS: The capsule consists of a plastic cylinder containing high-activity iodine-125 seeds and four restraining legs. Twelve patients with recurrent (n = 11) or inoperable carcinoma (n = 1) received a median dose of 4,500 (range, 2,633-6,299) cGy at a 1-cm radius from the center of the implant. RESULTS: No acute toxicities were observed. Five patients had complete regression of the endobronchial tumor, evidenced at bronchoscopy 2 months after therapy, and four patients had partial regression. Three patients failed to return for bronchoscopy. Symptomatic relief was achieved in eight of 10 patients with dyspnea, four of nine with cough, and two of three with hemoptysis. The median survival of the 12 patients was 6 months. The actuarial 1-year survival rate was 25%. CONCLUSION: This capsule is safe and efficacious in treating recurrent or inoperable carcinoma of the lung.

Endobronchial metastasis.

Endobronchial metastases from nonpulmonary neoplasms are rare. Since 1971, we have treated 23 patients with endobronchial metastases, the findings for which form the basis of this article. Many types of primary tumors are capable of endobronchial metastases, although breast, colon, and renal carcinomas predominate. The mean time from the diagnosis of the primary carcinoma to the diagnosis of endobronchial metastases was 59.9 months. Bronchoscopic results were diagnostic in all cases. Although the mean time for the appearance of endobronchial metastases is almost 5 years, on examination the majority of patients will have symptomatic extrabronchial metastatic disease, the quality of their survival will often be poor, and their survival time will be limited (12.5 months). Surgical resection should be confined to patients with localized disease.

Effect of uvulopalatopharyngoplasty on upper airway collapsibility in obstructive sleep apnea.

Previous investigators have demonstrated variable responses to uvulopalatopharyngoplasty (UPP) in patients with obstructive sleep apnea. We hypothesized that this variability is due to either (1) differences in baseline pharyngeal collapsibility preoperatively or (2) differences in magnitude of the decrease in pharyngeal collapsibility resulting from surgery. To determine the relationship between changes in collapsibility and the response to UPP surgery, we measured the upper airway critical pressure (Pcrit) before and after UPP in 13 patients with obstructive sleep apnea. During non-REM sleep, maximal inspiratory airflow (VImax) was quantitated by varying the level of nasal pressure (PN), and Pcrit was determined by the level of PN below which VImax ceased. A positive response to UPP was defined by a greater than or equal to 50% fall in non-REM disordered breathing rate (DBR). In the entire group, UPP resulted in significant decreases in DBR from 71.1 +/- 22.4 to 44.7 +/- 38.4 episodes/h (p = 0.025) and in Pcrit from 0.2 +/- 2.4 to -3.1 +/- 5.4 cm H2O (p = 0.016). Moreover, the percent change in DBR was correlated significantly with the change in Pcrit (p = 0.001). Subgroup analysis of responders and nonresponders demonstrated that significant differences in Pcrit were confined to the responders. Specifically, responders demonstrated a significant fall in Pcrit from -0.8 +/- 3.0 to -7.3 +/- 4.9 cm H2O (p = 0.01), whereas no significant change in Pcrit was detected in the nonresponders (1.1 +/- 1.6 versus 0.6 +/- 2.0 cm H2O. No clinical, polysomnographic, or physiologic predictors of a favorable response were found preoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)

Bronchoscopic brachytherapy.

Increasing lung cancer mortality has created renewed interest in the bronchoscopic use of isotopes for palliation of recurrent airway carcinomas. In the first part of this paper we report our clinical experience with iodine-125 implantation for treatment of endobronchial carcinomas in 18 patients followed until death. Symptoms of cough, hemoptysis, and dyspnea were most effectively relieved with tumors limited to the bronchial lumen. Contraindications to this procedure include extensive extrabronchial tumors causing airway compression and severe debility. In the second part of this paper the development of a new isotope delivery system designed to overcome technical difficulties experienced in the treatment of some patients with interstitial iodine 125 is described. An isotope capsule was constructed to permit insertion and removal by means of a fiberoptic bronchoscope. This device was successfully tested in animals and is now approved for clinical trials. It represents a unique, new modality for treatment of superficial, multifocal, and less-advanced recurrent bronchogenic carcinomas.

Diagnosis of lung allograft rejection by bronchial intraepithelial Leu-7 positive T lymphocytes.

Currently there is no reliable technique for the diagnosis of lung allograft rejection. The presence of intraepithelial lymphocytes expressing the Leu-7 antigen is a specific marker of renal rejection. We examined whether immunoperoxidase techniques that detect Leu-7 positive lymphocytes could be used to diagnose lung rejection in heart-lung transplant recipients. In lungs from two autopsied patients with lung allograft rejection, numerous Leu-7 positive lymphocytes were present in the donor bronchial mucosa (32 and 65 cells/section), submucosa (23 and 80 cells/section), and submucosal glands (7 and 19 cells/section). These Leu-7 positive lymphocytes were associated with proximal airway injury, including squamous metaplasia, destruction of submucosal glands, and ulceration. In one case, there was bronchiectasis. Both cases also had distal airway bronchiolitis obliterans. In contrast, Leu-7 positive lymphocytes were not identified in the epithelium of the native trachea of these two patients; nor were they found in the bronchial epithelium of two sets of transplanted lungs without evidence of rejection. Only rare Leu-7 positive lymphocytes were evident in the epithelium (0 to 2 cells/section) and submucosal glands (0 to 1 cell/section) of 20 lungs from autopsied patients who had not received a transplant. Application of this technique to epithelial biopsy specimens obtained at bronchoscopic examinations demonstrated that it could be applied to the diagnosis of rejection in living heart-lung transplant recipients.