A DNA methylation atlas of normal human cell types.

DNA methylation is a fundamental epigenetic mark that governs gene expression and chromatin organization, thus providing a window into cellular identity and developmental processes1. Current datasets typically include only a fraction of methylation sites and are often based either on cell lines that underwent massive changes in culture or on tissues containing unspecified mixtures of cells2-5. Here we describe a human methylome atlas, based on deep whole-genome bisulfite sequencing, allowing fragment-level analysis across thousands of unique markers for 39 cell types sorted from 205 healthy tissue samples. Replicates of the same cell type are more than 99.5% identical, demonstrating the robustness of cell identity programmes to environmental perturbation. Unsupervised clustering of the atlas recapitulates key elements of tissue ontogeny and identifies methylation patterns retained since embryonic development. Loci uniquely unmethylated in an individual cell type often reside in transcriptional enhancers and contain DNA binding sites for tissue-specific transcriptional regulators. Uniquely hypermethylated loci are rare and are enriched for CpG islands, Polycomb targets and CTCF binding sites, suggesting a new role in shaping cell-type-specific chromatin looping. The atlas provides an essential resource for study of gene regulation and disease-associated genetic variants, and a wealth of potential tissue-specific biomarkers for use in liquid biopsies.

Human Nasal and Lung Tissues Infected Ex Vivo with SARS-CoV-2 Provide Insights into Differential Tissue-Specific and Virus-Specific Innate Immune Responses in the Upper and Lower Respiratory Tract.

The nasal mucosa constitutes the primary entry site for respiratory viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). While the imbalanced innate immune response of end-stage coronavirus disease 2019 (COVID-19) has been extensively studied, the earliest stages of SARS-CoV-2 infection at the mucosal entry site have remained unexplored. Here, we employed SARS-CoV-2 and influenza virus infection in native multi-cell-type human nasal turbinate and lung tissues ex vivo, coupled with genome-wide transcriptional analysis, to investigate viral susceptibility and early patterns of local mucosal innate immune response in the authentic milieu of the human respiratory tract. SARS-CoV-2 productively infected the nasal turbinate tissues, predominantly targeting respiratory epithelial cells, with a rapid increase in tissue-associated viral subgenomic mRNA and secretion of infectious viral progeny. Importantly, SARS-CoV-2 infection triggered robust antiviral and inflammatory innate immune responses in the nasal mucosa. The upregulation of interferon-stimulated genes, cytokines, and chemokines, related to interferon signaling and immune-cell activation pathways, was broader than that triggered by influenza virus infection. Conversely, lung tissues exhibited a restricted innate immune response to SARS-CoV-2, with a conspicuous lack of type I and III interferon upregulation, contrasting with their vigorous innate immune response to influenza virus. Our findings reveal differential tissue-specific innate immune responses in the upper and lower respiratory tracts that are specific to SARS-CoV-2. The studies shed light on the role of the nasal mucosa in active viral transmission and immune defense, implying a window of opportunity for early interventions, whereas the restricted innate immune response in early-SARS-CoV-2-infected lung tissues could underlie the unique uncontrolled late-phase lung damage of advanced COVID-19. IMPORTANCE In order to reduce the late-phase morbidity and mortality of COVID-19, there is a need to better understand and target the earliest stages of SARS-CoV-2 infection in the human respiratory tract. Here, we have studied the initial steps of SARS-CoV-2 infection and the consequent innate immune responses within the natural multicellular complexity of human nasal mucosal and lung tissues. Comparing the global innate response patterns of nasal and lung tissues infected in parallel with SARS-CoV-2 and influenza virus, we found distinct virus-host interactions in the upper and lower respiratory tract, which could determine the outcome and unique pathogenesis of SARS-CoV-2 infection. Studies in the nasal mucosal infection model can be employed to assess the impact of viral evolutionary changes and evaluate new therapeutic and preventive measures against SARS-CoV-2 and other human respiratory pathogens.

The American Society of Thoracic Surgery Score versus EuroSCORE I and EuroSCORE II in Israeli Patients Undergoing Cardiac Surgery.

BACKGROUND: Recently, Israel established the first national-level adult cardiac surgery database, which was linked to the Society of Thoracic Surgeons (STS). OBJECTIVES: To validate and compare the STS predicted risk of mortality (PROM) to logistic EuroSCORE I (LESI) and EuroSCORE II (ESII) in Israeli patients undergoing cardiac surgery. METHODS: We retrospectively studied 1279 consecutive patients who underwent cardiac surgeries with a calculable PROM. Data were prospectively entered into our database and used to calculate PROM, LESI, and ESII. Scores were normalized and correlated using linear regression and Pearson's test. To examine model calibration, we plotted the total observed versus expected mortality for each score and across five risk-score subgroups. Model discrimination was assessed by measuring the area under the receiver operating curves. RESULTS: The observed 30-day operative mortality was 1.95%. The median (IQ1; IQ3) PROM, LESI, and the ESII scores were 1.45% (0.69; 3.22), 4.54% (2.28; 9.27), and 1.88% (1.18; 3.54), respectively, with observed over expected ratios of 0.63 (95% confidence interval [95%CI] 0.42-0.93), 0.59 (95%CI 0.40-0.87), and 0.24 (95%CI 0.17-0.36), respectively, (STS vs. ESII P = 0.36, STS vs. LESI P = 0.0001). There was good correlation among all scores. All models overestimated mortality. Model discrimination was high and similar for all three scores. Model calibration of the STS, PROM, and ESII were more accurate than the LESI, particularly in higher risk subgroups. CONCLUSIONS: All scores overestimated mortality. In Israeli patients, the STS, PROM, and ESII risk-scores were more reliable metrics than LESI, particularly in higher risk patients.

Outcomes of extracranial stereotactic body radiation therapy for induced oligometastatic non-small cell lung cancer on novel systemic therapy.

Background: Stereotactic body radiation therapy (SBRT) is often delivered in patients with oligometastatic disease (OMD). However, the specific subset of patients with polymetastatic non-small cell lung cancer (NSCLC) on novel systemic therapies who develop induced oligopersistant disease (OpersisD) or oligoprogressive disease (OprogD), as defined by the European Organisation for Research and Treatment of Cancer (EORTC) OMD classification, has not been well described. This study explores the outcomes of patients treated with this strategy. Methods: Patients with stage IV NSCLC being treated with osimertinib or immune checkpoint inhibitors (ICIs) who received extracranial SBRT for OpersisD or OprogD were identified in our retrospective analysis. Outcomes reported include progression-free survival (PFS), time to change of systemic treatment (TTCST), overall survival (OS), local control (LC) and treatment-related toxicity. Results: Forty-nine patients received SBRT for OpersisD (34.7%) or OprogD (65.3%) at a median of 5.8 and 15.3 months after start of systemic therapy, respectively. 55.1% received concurrent osimertinib and 44.9% received ICI. Seventy-seven extracranial lesions were treated with various fractionation schemas. At a median of 18.8 months follow-up from first SBRT, LC was achieved in 92.2% of total lesions treated (71). The 1-year OS was 91.7% for OpersisD and 83.3% for OprogD. OpersisD compared to OprogD had a longer median PFS (18.3 vs. 6.1 months) and longer median TTCST (23.6 vs. 13.5 months), median OS was not reached for either cohort. On multivariate analysis, patients treated with osimertinib had shorter PFS (HR: 2.20; 95% CI: 1.01-4.82; P=0.048) and shorter TTCST (HR: 2.83; 95% CI: 1.09-7.33; P=0.032). One patient (2%) experienced grade 3 pneumonitis after SBRT, and no grade 4-5 toxicities were reported with SBRT treatment. Conclusions: This study indicates that SBRT for OpersisD or OprogD in Stage IV NSCLC patients on osimertinib or ICIs is safe, very well tolerated, and may prolong the time before needing a shift in systemic therapy. Further prospective research is needed to validate and expand upon these findings.

The DNA methylome of human vascular endothelium and its use in liquid biopsies.

BACKGROUND: Vascular endothelial cells (VECs) are an essential component of each tissue, contribute to multiple pathologies, and are targeted by important drugs. Yet, there is a shortage of biomarkers to assess VEC turnover. METHODS: To develop DNA methylation-based liquid biopsies for VECs, we determined the methylome of VECs isolated from freshly dissociated human tissues. FINDINGS: A comparison with a human cell-type methylome atlas yielded thousands of loci that are uniquely unmethylated in VECs. These sites are typically gene enhancers, often residing adjacent to VEC-specific genes. We also identified hundreds of genomic loci that are differentially methylated in organotypic VECs, indicating that VECs feeding specific organs are distinct cell types with a stable epigenetic identity. We established universal and lung-specific VEC markers and evaluated their presence in circulating cell-free DNA (cfDNA). Nearly 2.5% of cfDNA in the plasma of healthy individuals originates from VECs. Sepsis, graft versus host disease, and cardiac catheterization are associated with elevated levels of VEC-derived cfDNA, indicative of vascular damage. Lung-specific VEC cfDNA is selectively elevated in patients with chronic obstructive pulmonary disease (COPD) or lung cancer, revealing tissue-specific vascular turnover. CONCLUSIONS: VEC cfDNA biomarkers inform vascular dynamics in health and disease, potentially contributing to early diagnosis and monitoring of pathologies, and assessment of drug activity. FUNDING: This work was supported by the Beutler Research Program, Helmsley Charitable Trust, JDRF, Grail and the DON Foundation (to Y.D.). Y.D holds the Walter & Greta Stiel Chair in heart studies. B.G., R.S., J.M., D.N., T.K., and Y.D. filed patents on cfDNA analysis.

Extracellular matrix constituents interfere with Newcastle disease virus spread in solid tissue and diminish its potential oncolytic activity.

Advanced melanoma cells, characterized by resistance to chemotherapy, have been shown to be highly sensitive to oncolysis by Newcastle disease virus (NDV). In the present study, we investigated the capacity of NDV to specifically infect and spread into solid tissues of human melanoma and lung carcinoma, in vivo and ex vivo. For this purpose a new model of SCID-beige mice implanted with human melanoma was developed. Surprisingly, the replication competent NDV-MTH and the attenuated, single-cycle replication NDV-HUJ strains, demonstrated a similar oncolytic activity in the melanoma-implanted mice. Further, ex vivo analysis, using organ cultures derived from the melanoma tissues indicated a limited spread of the two NDV strains in the tissue. Extracellular matrix (ECM) molecules, notably heparin sulfate and collagen, were found to limit viral spread in the tissue. This observation was validated with yet another solid tumour of human lung carcinoma. Taken together, the results indicate that the ECM acts as a barrier to virus spread within solid tumour tissues and that this restriction must be overcome to achieve effective oncolysis with NDV.

Infant lungs are preferentially infected by adenovirus and herpes simplex virus type 1 vectors: role of the tissue mesenchymal cells.

BACKGROUND: Adenovirus (AD) and herpes-simplex-virus-1 (HSV-1) have been extensively applied as vectors for gene and cancer therapy in clinical trials. AD5, from which the vector was constructed, is a common respiratory virus that infects mainly infants, yet the reasons for infant sensitivity to infection, other than immunity, are not clear. HSV-1, usually a neurotropic virus, may also cause severe pneumonia or disseminated diseases in infants and immunocompromised patients. METHODS: The tropism of these viruses to different human and mouse lung tissues of newborn and adult was studied in an ex vivo organ culture and it was also applied in vivo using a murine model. RESULTS: The data obtained indicated preferential viral infection of young lung tissues versus adult tissues in organ culture. Further studies indicated that the preferential infection of young tissues was not related to differences in receptor expression or exposure but rather to the different distribution of cell types in these tissues. Murine and human young lungs consist of a relative abundance of mesenchymal cells and these cells were much more susceptible to viral infection compared to adjacent epithelial-pneumocyte cells. These observations were further confirmed using an in vivo model of mouse infection. CONCLUSIONS: The similarity of the human and mouse tissues, with respect to viral vector tropism, validates the mouse model in studies of gene transfer to the lung. Furthermore, the results should facilitate the improved design of gene therapy trials for lung-related diseases in young and adults patients. Copyright © 2011 John Wiley & Sons, Ltd.

Outcomes of sublobar resection vs lobectomy for invasive clinical stage T1N0 non-small-cell lung cancer: A propensity-match analysis.

BACKGROUND: The role of sub lobar resection (SLR; either segmentectomy or wedge resection) vs lobectomy (LBCT) for invasive clinical stage T1N0 non-small-cell-lung-cancer (NSCLC) has not been fully established yet. AIM: We aimed to characterize the preoperative parameters leading to selecting SLR and compare the overall survival (OS) and disease-free survival (DFS) of these two surgical approaches. METHODS: Clinical data on 162 patients (LBCT-107; SLR-55) were prospectively entered in our departmental database. Preoperative parameters associated with the performance of SLR were identified using univariate and multivariate cox regression analysis. The Kaplan-Meier method was used to compute OS and DFS. Comparison between LBCT and SLR groups and 32 propensity-matched groups was performed using Log-rank test. RESULTS: Median follow-up time for the LBCT and SLR groups was 4.76 (Inter-quartile range [IQR] 2.96 to 8.23) and 3.38 (IQR 2.9 to 6.19) years respectively. OS and DFS rates were similar between the two groups in the entire cohort (OS-LBCT vs SLR P = .853, DSF-LBCT vs SLR P = .653) and after propensity matching (OS-LBCT vs SLR P = .563 DSF-LBCT vs SLR P = .632). Specifically, Two- and five-year OS rates for LBCT and SLR were 90.6.% vs 92.7%, 71.8% vs 75.9% respectively. Independent predictors of selecting for SLR included older age (P < .001), reduced FEV1% (P = .026), smaller tumor size (P = .025), smaller invasive component (P = .021) and higher American Society of Anesthesiology scores (P = .014). CONCLUSIONS: In 162 consecutive and 32 matched cases, SLR and lobar resection had similar overall and disease-free survival rates. SLR may be considered as a reasonable oncological procedure in carefully selected T1N0 NSCLC patients that present with multiple comorbidities and relatively small tumors.

The pattern of thoracic trauma after suicide terrorist bombing attacks.

BACKGROUND: The worldwide escalation in the volume of suicide terrorist bombing attacks warrants special attention to the specific pattern of injury associated with such attacks. The goal of this study was to characterize thoracic injuries inflicted by terrorist-related explosions and compare pattern of injury to penetrating and blunt thoracic trauma. METHODS: Prospectively collected database of patients with chest injury who were admitted to Hadassah Hospital Level I trauma centre, in Jerusalem, Israel, from October 2000 to December 2005. Patients were divided into three groups according to the mechanism of injury: terrorist explosions (n = 55), gunshot wounds (GSW; n = 78), and blunt trauma (n = 747). RESULTS: There were many female victims after suicide bombing attacks (49.1%) compared with GSW (21.8%) and blunt trauma (24.6%; p = 0.009). The number of body regions injured was significantly higher in the terror group compared with the GSW and blunt groups (median, 4, 2, and 3, respectively, p < 0.0001). The pattern of chest injury after suicide bombing attacks was caused by a unique combination of the effects of the blast wave and penetrating shrapnel. More than half (52.7%) of the terror victims suffered from lung contusion and 25 (45.5%) required tube thoracostomy. Five patients (9.1%) underwent thoracotomy for lung lacerations (n = 3), injury to great vessels (n = 2), cardiac lacerations (n = 1), and esophageal injury (n = 1). Penetrating shrapnel was the mechanism of injury in all these cases. CONCLUSIONS: Injury inflicted by terrorist bombings causes a unique pattern of thoracic wounds. Victims are exposed to a combination of lung injury caused by the blast wave and penetrating injury caused by metallic objects.

Invasive Scytalidium dimidiatum infection in an immunocompetent adult.

Scytalidium dimidiatum, a dematiaceous fungus, has been well established as an agent of dermatomycosis. There are few reports of invasive infection caused by S. dimidiatum; most infections occurred in immunocompromised hosts. We present an immunocompetent patient with pleural S. dimidiatum infection and review nine other published cases of invasive S. dimidiatum infections.

Matrix metalloproteinase 12 promotes tumor propagation in the lung.

OBJECTIVE: Past studies are inconsistent with regard to the role of matrix metalloproteinase 12 in lung tumorigenesis. This is due, in part, to differential tumorigenesis based on tumor-derived versus immune-derived matrix metalloproteinase 12 expression. Our study aims to thoroughly dissect the role of matrix metalloproteinase 12 in lung tumorigenesis. METHODS: We tested matrix metalloproteinase 12 expression and the association with prognosis using a tissue array and a published non-small cell lung cancer gene expression database. In addition, we characterized the contribution of matrix metalloproteinase 12 to tumor propagation in the lung using a series of in vitro and in vivo studies. RESULTS: Tumor cells of a diverse set of human lung cancers stained positive for matrix metalloproteinase 12, and high matrix metalloproteinase 12 mRNA levels in the tumor were associated with reduced survival. The lung microenvironment stimulated endogenous production of matrix metalloproteinase 12 in lung cancer cells (human 460 lung cancer cell line, Lewis lung carcinoma). In vitro, matrix metalloproteinase 12 knockout Lewis lung carcinoma and Lewis lung carcinoma cells had the same proliferation rate, but Lewis lung carcinoma showed increased invasiveness. In vivo, deficiency of matrix metalloproteinase 12 in Lewis lung carcinoma cells, but not in the host, reduced tumor growth and invasiveness. CONCLUSIONS: We suggest that tumor cell-derived matrix metalloproteinase 12 promotes tumor propagation in the lung and that in the context of pulmonary malignancies matrix metalloproteinase 12 should further be tested as a potential novel therapeutic target.

Minimally invasive procedures for diagnosis of traumatic right diaphragmatic tears: a method for correct diagnosis in selected patients.

Traumatic rupture of the diaphragm is no longer uncommon. Because of the increasing frequency of motor vehicle accidents, the rate of blunt trauma to the chest and abdomen, which are the most common causes of diaphragmatic rupture, is increased as well. However, the diagnosis is frequently missed or delayed because of the lack of sensitivity and specificity of imaging modalities. Diagnostic laparoscopy is considered a standard tool for penetrating injuries to the left diaphragm and is widely practiced in selected cases. Right diaphragmatic tears, however, are more difficult to diagnose because of the sealing effect of the liver. Blunt abdominal trauma can cause large right diaphragmatic tears, causing liver incarcerations and respiratory compromise, therefore demanding the need for a comparable diagnostic tool. A high index of suspicion, together with knowledge of the mechanism of trauma, is the key factor for the correct diagnosis. Once the diagnosis has been considered, diagnostic laparoscopy and/or diagnostic thoracoscopy should be performed to confirm or rule out this injury. Factors suggestive of a right diaphragmatic tear include newly or progressive elevation of the right diaphragm and respiratory distress without underlining lung injury. The timing of the procedure should be in accordance with the hemodynamic and respiratory status of the patient. This procedure should be performed semielectively if there are no other indications for surgical intervention.

Computed tomography screening for lung cancer: applicability of an international protocol in a single-institution environment.

BACKGROUND: The purpose of this study was to assess the applicability of an annual low-dose computed tomography (CT) screening program for lung cancer in a single institution in Israel, which has a relatively lower prevalence of lung cancer compared with other Western countries, and to examine stage distribution of detected lung cancers. PATIENTS AND METHODS: A cohort of 842 former and current smokers underwent baseline low-dose CT screening and a total of 942 annual repeat screenings over a period of 68 months. The definition of positive results on baseline and repeat screening and their diagnostic workup were guided by the common International Early Lung Cancer Action Program protocol. Recommendations for biopsy of suspicious nodules were based on nodule size, nodule growth, non-resolution following antibiotic therapy, and positron emission tomography scan. RESULTS: The test result was positive in 102 of the 842 baseline screenings (12%) and in 45 of the 942 annual repeat screenings (5%), and biopsy was recommended in 12 baseline and 2 annual screenings. Twelve of the 14 cancers diagnosed (86%) were stage I tumors. CONCLUSION: Our study indicates that the adoption of a common international protocol is feasible, even in a very different clinical setting, yielding a high proportion of early-stage lung cancers.

Massive empyema caused by Mycoplasma pneumoniae in an adult: a case report.

BACKGROUND: Mycoplasma pneumoniae is responsible for more than 20% of community acquired pneumonia cases, and capable of causing upper respiratory illness as well. Complications of M.pneumoniae infections include CNS involvement but other as pericarditis were also reported. The lack of feasible culture methods and under appreciation of the pathogens ability to cause invasive disease leads to reduced number of diagnosed M.pneumoniae related complications. In contrast to many other respiratory pathogens causing pneumonia, M. pneumoniae related severe pleural complications were almost never reported. CASE PRESENTATION: We report a previously healthy 57 years old woman presented with indolent massive right pleural effusion, leukocytosis and elevated ESR. Extensive microbiological evaluation didn't reveal any pathogen in the pus even before antibiotic treatment was started. Surprisingly, M.pneumoniae DNA was detected in the pus from the empyema using PCR designed to detect M.pneumoniae. A serological assay (Serodia-Myco II) using convalescent serum was indeterminate with a titer of 1:80. The patient responded well to a treatment that included right thoracotomy with pleural decortication and a combination of antibiotics and anti-inflammatory medications. CONCLUSION: M.pneumoniae related empyema was never reported before in adult patients and was reported in only a few pediatric patients. In our patient there was no evidence to any common pathogens even before initiating antibiotic treatment. The only pathogen detected was M.pneumoniae. In this patient, serology was not helpful in establishing the diagnosis of M.pneumoniae related diseases, as was suggested before for older patients. We suggest that M.pneumoniae related empyema is probably under-diagnosed complication due to insensitivity of serology in older patients and under use of other diagnosis methods.

Preoperative thallium scanning, selective coronary revascularization, and long-term survival after major vascular surgery.

BACKGROUND: Ischemia on thallium scanning is a strong predictor of long-term mortality in CAD patients. Whether coronary revascularization (CR) in patients with significant ischemia on preoperative thallium scanning (PTS) improves long-term survival after major vascular surgery has not been determined. METHODS AND RESULTS: The perioperative data, including PTS and subsequent CR in patients with moderate to severe reversible ischemia on PTS, and long-term survival of 502 consecutive patients who underwent 578 major vascular procedures were analyzed retrospectively. Patients with PTS who ultimately did not undergo the planned vascular operation were also studied. Cox regression and propensity score analyses were used to analyze survival. A total of 407 patients (81.1%) had PTS: 221 (54.3%) had no or mild defects (group I); 50 (12.3%) had moderate-severe fixed defects (group II); 62 (15.2%) had moderate-severe reversible ischemia yet did not undergo CR (group III); and 74 (18.2%) had moderate-severe reversible ischemia and subsequent CR by CABG (36) or PTCA (38; group IV). Patients who sustained major complications as a result of the preoperative cardiac workup were included in group IV. By multivariate analysis, age, type of vascular surgery, presence of diabetes, previous myocardial infarction, and moderate-severe ischemia on PTS independently predicted mortality (P=0.001, 0.009, 0.039, 0.006, and 0.029, respectively), and preoperative CR predicted improved survival (OR 0.52, P=0.018). Group IV had better survival than group III even when subdivided according to normal and reduced left ventricular function (OR 0.40 and 0.41, P=0.035 and 0.021, respectively). CONCLUSIONS: Long-term survival after major vascular surgery is significantly improved if patients with moderate-severe ischemia on PTS undergo selective CR.

When should we discontinue antiarrhythmic therapy for atrial fibrillation after coronary artery bypass grafting? A prospective randomized study.

BACKGROUND: New-onset atrial fibrillation after coronary artery bypass grafting is common. Medical therapy includes various antiarrhythmic drugs to control heart rate and restore sinus rhythm. The purpose of this study was to determine the duration of antiarrhythmic therapy after discharge from the hospital. METHODS: One hundred twenty-nine patients in whom new atrial fibrillation after coronary artery bypass grafting developed and successfully reverted to sinus rhythm were prospectively randomized at dismissal to receive antiarrhythmic therapy for 1 week (group A; n = 44), 3 weeks (group B; n = 42), or 6 weeks (group C; n = 43). Patients were followed up for an additional 4 weeks after discontinuation of antiarrhythmic therapy for detection of recurrent atrial fibrillation. RESULTS: The incidence of new atrial fibrillation during the study period was 21.2% (256/1206). Among the 129 patients who consented to the study, conversion to sinus rhythm was accomplished with the following medications: amiodarone (group A, 82%; group B, 93%; group C, 88%; P = .29), digoxin (group A, 16%; group B, 7%; group C, 7%; P = .29), beta-blockers (group A, 27%; group B, 19%; group C, 14%; P = .30), calcium channel blockers (group A, 2%; group B, 2%; group C, 0%; P = .60), quinidine (group A, 2%; group B, 2%; group C, 7%; P = .44), and procainamide (group A, 4.5%; group B, 2%; group C, 0%; P = .37). Follow-up was completed in 128 patients (99.2%). There was no significant difference in the recurrence of atrial fibrillation among groups (0%, 2%, and 0% for groups A, B, and C, respectively). CONCLUSIONS: Patients with new atrial fibrillation after coronary artery bypass grafting, converted to normal sinus rhythm before hospital discharge, have a benign course. Antiarrhythmic therapy as short as 1 week may be appropriate in these patients.

In the hunt for therapeutic targets: mimicking the growth, metastasis, and stromal associations of early-stage lung cancer using a novel orthotopic animal model.

BACKGROUND: The existing shortage of animal models that properly mimic the progression of early-stage human lung cancer from a solitary confined tumor to an invasive metastatic disease hinders accurate characterization of key interactions between lung cancer cells and their stroma. We herein describe a novel orthotopic animal model that addresses these concerns and consequently serves as an attractive platform to study tumor-stromal cell interactions under conditions that reflect early-stage lung cancer. METHODS: Unlike previous methodologies, we directly injected small numbers of human or murine lung cancer cells into murine's left lung and longitudinally monitored disease progression. Next, we used green fluorescent protein-tagged tumor cells and immuno-fluorescent staining to determine the tumor's microanatomic distribution and to look for tumor-infiltrating immune cells and stromal cells. Finally, we compared chemokine gene expression patterns in the tumor and lung microenvironment. RESULTS: We successfully generated a solitary pulmonary nodule surrounded by normal lung parenchyma that grew locally and spread distally over time. Notably, we found that both fibroblasts and leukocytes are recruited to the tumor's margins and that distinct myeloid cell attracting and CCR2-binding chemokines are specifically induced in the tumor microenvironment. CONCLUSION: Our orthotopic lung cancer model closely mimics the pathologic sequence of events that characterizes early-stage human lung cancer propagation. It further introduces new means to monitor tumor-stromal cell interactions and offers unique opportunities to test therapeutic targets under conditions that reflect early-stage lung cancer. We argue that for such purposes our model is superior to lung cancer models that are based either on genetic induction of epithelial transformation or on ectopic transplantation of malignant cells.

Protection of myocardium by cyclosporin A and insulin: in vitro simulated ischemia study in human myocardium.

BACKGROUND: The efficacy of myocardial protection by cyclosporin A (CSA) and insulin was tested in human right atrial myocardial slices subjected to simulated ischemia and reoxygenation. METHODS: Slices of right atrial trabeculae were obtained from patients undergoing elective cardiac surgery. Trabeculae were incubated with oxygenated glucose containing phosphate buffered saline (O(2), G-PBS). After 30 minutes of stabilization the sections were exposed to 90 minutes of simulated ischemia (N(2), PBS without glucose) followed by 90 minutes reoxygenation (O(2), G-PBS). Cyclosporin A (0.2 micromol/L) or insulin (5 mU/mL) was added during the stabilization period prior the ischemia. Cell viability was measured by using 3-[4.5 dimethylthiazol 2-yl]-2,5-diphenyltetrazolium bromide (MTT), which is cleaved by active mitochondrial dehydrogenases of living cells. RESULTS: The viability of untreated slices (control) was 30.45% +/- 2.5% versus 52.65% +/- 4.4% in the CSA treated slices, p less than 0.001. The extent of protection by CSA was affected by oral antiglycemic drugs (glibenclamide). The effect obtained by CSA was inhibited by 5-hydroxydecanoate (5HD), a specific blocker of mitochondrial K(ATP) channels. Protection of the myocardial slices with insulin appears to be superior and not affected by the medication before surgery. This protection was maximal when insulin was present during both preischemic equilibration and reoxygenation periods (68.9% +/- 9.3% viability with insulin versus 33.2% +/- 6.9% in the control, p < 0.001). CONCLUSIONS: Protection of right atrial trabeculae slices with insulin is superior to that obtained with CSA and is independent of preoperative medication.

The surgical approach to infective endocarditis: 10 year experience.

BACKGROUND: About 40% of patients with infective endocarditis will require surgical treatment. The guidelines for such treatment were formulated by the American College of Cardiology and American Heart Association in 1998. OBJECTIVES: To examine our experience with surgical treatment of infective endocarditis in light of these guidelines. METHODS: Surgery was performed in 59 patients with infective endocarditis between 1990 and 1999. The patients' mean age was 48 years (range 13-80). The indications for surgery were hemodynamic instability, uncontrolled infection, and peripheral embolic events. The surgical treatment was based on elimination of infection foci and correction of the hemodynamic derangement. These objectives were met with valve replacement in the majority of patients. Whenever conservative surgery was possible, resection of vegetation and subsequent valve repair were performed and the native valve was preserved. RESULTS: Six patients (10%) died perioperatively from overwhelming sepsis (n = 3), low cardiac output (n = 2) and multiogran failure (n = 1). The mean hospital stay was 15.6 days. Of 59 patients, 47 (80%) underwent valve replacement and in 11 (19%) the surgical treatment was based on valve repair. After 1 year of follow-up there was no re-infection. CONCLUSION: The new guidelines for surgical treatment of infective endocarditis allow better selection of patients and timing of surgery for this aggressive disease, which consequently decreases the mortality rate. Valve repair is feasible and is preferred whenever possible. According to the new guidelines, patients with neurologic deficit in our series would not have been operated upon, potentially decreasing the operative mortality to 7%.

Cardiac surgery in octogenarians--a better prognosis in coronary artery disease.

BACKGROUND: Cardiac surgery is being performed with increasing frequency in patients aged 80 years and older. OBJECTIVES: To examine the long and short-term results of surgery in this age group. METHODS: We retrospectively investigated 202 consecutive patients aged 80 years or older who underwent cardiac surgery between 1991 and 1999, Ninety-six operations (48%) were urgent. RESULTS: The study group comprised 140 men (69%) and 62 women (31%) with a mean age of 82.1 years (range 80-89). Preoperatively, 120 patients (59%) had unstable angina, 37 (18%) had left main coronary artery disease, 22 (11%) had renal failure, 17 (8.5%) had a history of stroke and 13 (6.5%) had previous cardiac surgery. Hospital mortality for the whole group was 7.4%. Postoperative complications included: re-exploration for bleeding in 15 (7.4%), stroke in 8 (4%), sternal wound infection in 3 (1.5%), low cardiac output in 17 (8.4%), new Q wave myocardial infarction in 5 (2.5%), renal failure in 17 (8.5%), and atrial fibrillation in 71 (35%). The actuarial survival for patients discharged from the hospital was 66% at 5 years and 46% at 8 years. The type of surgical procedure was significantly associated with increased early mortality (coronary artery bypass grafting only in 2.9%, CABG + valve in 16.1%, valve only in 16.7%; P = 0.01). Significant predictors (P < 0.05) for late mortality included type of surgical procedure, congestive heart failure, and postoperative low cardiac output. CONCLUSIONS: When appropriately applied in selected octogenarians, cardiac surgery can be performed with acceptable mortality and good long-term results.