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White spot syndrome virus (WSSV) is known to upregulate glycolysis to supply biomolecules and energy for the virus's replication. At the viral genome replication stage, lactate dehydrogenase (LDH), a glycolytic enzyme, shows increased activity without any increase in expression. In the present study, yeast 2-hybrid screening was used to identify WSSV proteins that interacted with LvLDH isoform 1 and 2, and these included the WSSV early protein WSSV004. The interaction between WSSV004 and LvLDH1/2 was confirmed by co-immunoprecipitation. Immunofluorescence showed that WSSV004 co-localized with LvLDH1/2 in the cytoplasm. dsRNA silencing experiments showed that WSSV004 was crucial for WSSV replication. However, although WSSV004 silencing led to the suppression of total LvLDH gene expression during the viral late stage, there was nevertheless a significant increase in LvLDH activity at this time. We also used affinity purification-mass spectrometry to identify cellular proteins that interact with WSSV004, and found a total of 108 host proteins and 3 WSSV proteins with which it potentially interacts. Bioinformatics analysis revealed that WSSV004 and its interacting proteins might be responsible for various biological pathways during infection, including vesicular transport machinery and RNA-related functions. Collectively, our study suggests that WSSV004 serves as a multifunctional modulator to facilitate WSSV replication., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

While it is known that cells with differential adhesion tend to segregate and preferentially sort, the physical forces governing sorting and invasion in heterogeneous tumors remain poorly understood. To investigate this, we tune matrix confinement, mimicking changes in the stiffness and confinement of the tumor microenvironment, to explore how physical confinement influences individual and collective cell migration in 3D spheroids. High levels of confinement lead to cell sorting while reducing matrix confinement triggers the collective fluidization of cell motion. Cell sorting, which depends on cell-cell adhesion, is crucial to this phenomenon. Burst-like migration does not occur for spheroids that have not undergone sorting, regardless of the degree of matrix confinement. Using computational Self-Propelled Voronoi modeling, we show that spheroid sorting and invasion into the matrix depend on the balance between cell-generated forces and matrix resistance. The findings support a model where matrix confinement modulates 3D spheroid sorting and unjamming in an adhesion-dependent manner, providing insights into the mechanisms of cell sorting and migration in the primary tumor and toward distant metastatic sites. STATEMENT OF SIGNIFICANCE: The mechanical properties of the tumor microenvironment significantly influence cancer cell migration within the primary tumor, yet how these properties affect intercellular interactions in heterogeneous tumors is not well understood. By utilizing calcium and calcium chelators, we dynamically alter collagen-alginate hydrogel stiffness and investigate tumor cell behavior within co-culture spheroids in response to varying degrees of matrix confinement. High confinement is found to trigger cell sorting while reducing confinement for sorted spheroids facilitates collective cell invasion. Notably, without prior sorting, spheroids do not exhibit burst-like migration, regardless of confinement levels. This work establishes that matrix confinement and intercellular adhesion regulate 3D spheroid dynamics, offering insights into cellular organization and migration within the primary tumor., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Dynamin, a 100-kDa GTPase, is one of the most-characterized membrane fission machineries catalyzing vesicle release from plasma membrane during endocytosis. The human genome encodes three dynamins: DNM1, DNM2 and DNM3, with high amino acid similarity but distinct expression patterns. Ever since the discoveries of dynamin mutations associated with human diseases in 2005, dynamin has become a paradigm for studying pathogenic mechanisms of mutant proteins from the aspects of structural biology, cell biology, model organisms as well as therapeutic strategy development. Here, we review the diseases and pathogenic mechanisms caused by mutations of DNM1 and DNM2, focusing on the activity requirement and regulation of dynamins in different tissues., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Some wastewater sources, such as agricultural waste and runoff, and industrial sewage, can degrade water quality. This study summarises the sources and corresponding mechanisms that trigger eutrophication in lakes. Additionally, the trophic status index and water quality index (WQI) which are effective tools for evaluating the degree of eutrophication of lakes, have been discussed. This study also explores the main nutrients (nitrogen and phosphorus) driving transformations in the water body and sediment. Lake Erhai was used as a case study, and it was found to be in a mesotrophic state, with N and P co-limitation before 2006, and only P limitation since 2006. Finally, effective measures to maintain sustainable development in the watershed are proposed, along with a framework for an early warning system adopting the latest technologies (geographic information systems (GIS), remote sensing (RS)) for preventing eutrophication., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Postoperative atrial fibrillation (POAF) frequently complicates cardiac surgery and is associated with worse outcomes. The cardiac autonomic nervous system is implicated in the pathogenesis of POAF., Objective: The purpose of this study was to determine the efficacy and safety of selective cardiac autonomic modulation in preventing POAF., Methods: In this randomized, double-blind, placebo-controlled trial, adults undergoing cardiac surgery were randomized 1:1 to intraoperative injection of 250 units onabotulinumtoxinA (botulinum toxin type A [BoNTA]) or placebo into epicardial fat pads. The study was powered to detect a 40% reduction in relative risk of POAF. Time to first episode of in-hospital POAF was the primary outcome, evaluated in patients receiving injection. Additionally, incidence of POAF, length of stay (LOS), and adverse events were examined., Results: The trial assigned 145 patients to injection, 15 of whom were dropped before treatment, leaving 130 patients for analysis. Overall, 36.5% (23/63) of BoNTA-treated patients developed POAF compared with 47.8% (32/67) of placebo-treated patients. The time-to-event analysis revealed a hazard ratio of 0.69 (95% confidence interval 0.41-1.19; P = .18) for the BoNTA vs placebo arm. There were no significant differences in postoperative hospital LOS (median [interquartile range] 6.0 [3.4] vs 6.2 [3.7] days; P = .51) or adverse events prolonging LOS (27/63 [42.9%] vs 30/67 [44.8%]; P = .83) in patients receiving BoNTA vs placebo., Conclusion: Epicardial injection of onabotulinumtoxinA was without discernible adverse effects, but we failed to detect a significant difference in risk of POAF. Future large-scale studies of epicardial onabotulinumtoxinA injection as a potential POAF prevention strategy should be designed to study smaller, but clinically meaningful, treatment effects., (Copyright © 2018 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Traditional Chinese Medicine (TCM) is an experiential form of medicine with a history dating back thousands of years. The present study aimed to utilize neural network analysis to examine specific prescriptions for colorectal cancer (CRC) in clinical practice to arrive at the most effective prescription strategy. The study analyzed the data of 261 CRC cases recruited from a total of 141,962 cases of renowned veteran TCM doctors collected from datasets of both the DeepMedic software and TCM cancer treatment books. The DeepMedic software was applied to normalize the symptoms/signs and Chinese herbal medicine (CHM) prescriptions using standardized terminologies. Over 20 percent of CRC patients demonstrated symptoms of poor appetite, fatigue, loose stool, and abdominal pain. By analyzing the prescription patterns of CHM, we found that Atractylodes macrocephala (Bai-zhu) and Poria (Fu-ling) were the most commonly prescribed single herbs identified through analysis of medical records, and supported by the neural network analysis; although there was a slight difference in the sequential order. The study revealed an 81.9% degree of similarity of CHM prescriptions between the medical records and the neural network suggestions. The patterns of nourishing Qi and eliminating dampness were the most common goals of clinical prescriptions, which corresponds with treatments of CRC patients in clinical practice. This is the first study to employ machine learning, specifically neural network analytics to support TCM clinical diagnoses and prescriptions. The DeepMedic software may be used to deliver accurate TCM diagnoses and suggest prescriptions to treat CRC., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

GC-MS urinary metabolomic analysis coupled with chemometrics is used to detect inborn errors of metabolism (IEMs), which are genetic disorders causing severe mental and physical debility and even sudden infant death. Orthogonal partial least squares discriminant analysis (OPLS-DA) is an efficient multivariate statistical method that conducts data analysis of metabolite profiling. However, performance degradation is often observed for OPLS-DA due to increasing size and complexity of metabolomic datasets. In this study, hybrid particle swarm optimization (HPSO) is employed to modify OPLS-DA by simultaneously selecting the optimal variable subset, associated weights and the appropriate number of orthogonal components, constructing a new algorithm called HPSO-OPLSDA. Investigating two IEMs, methylmalonic acidemia (MMA) and isovaleric acidemia (IVA), results suggest that HPSO-OPLSDA can significantly outperform OPLS-DA in terms of the discrimination between disease samples and healthy controls. Moreover, main discriminative metabolites are identified by HPSO-OPLSDA to aid the clinical diagnosis of IEMs, including methylmalonic-2, methylcitric-4(1) and 3-OH-propionic-2 for MMA and isovalerylglycine-1 for IVA., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Despite improving outcomes following lung transplantation, chronic rejection continues to limit survival. The predominant form of chronic rejection, bronchiolitis obliterans syndrome, has been associated with multiple etiologies including aspiration from gastroduodenal reflux. This article reviews the current literature with regards to the incidence of reflux following lung transplantation, the association of reflux with allograft dysfunction and survival, and the success of prevention and treatment of reflux in this patient population. Although antireflux surgery has been demonstrated to be safe in this population and leads to a stabilization of lung function in patients with reflux, there have not been definitive data that it improves survival.

Background: Rates of repeat lung transplantation have increased since implementation of the lung allocation score (LAS). The purpose of this study is to compare survival between repeat (ReTx) and primary (LTx) lung transplant recipients in the LAS era., Methods: We extracted data from 9,270 LTx and 456 ReTx recipients since LAS implementation, from the United Network for Organ Sharing registry. Propensity scoring was used to match ReTx and LTx recipients. Kaplan-Meier analysis compared survival between LTx and ReTx groups, with and without stratification based on time between first and second transplant. Multivariable Cox models estimated predictors of survival in lung recipients., Results: Comparing all ReTx to LTx demonstrates a survival advantage for LTx that is diminished with propensity score matching (p = 0.174). Considering LTx against ReTx greater than 90 days after the initial procedure, there are similar survival results (p < 0.067). In contrast, ReTx within 90 days was associated with a survival disadvantage that persisted despite matching (p = 0.011). In ReTx populations, factors conferring worse outcomes include intensive care unit admission, unilateral transplantation, poor functional status, and primary graft dysfunction as the indication for retransplantation (p < 0.05)., Conclusions: Late lung retransplantation appears to be as beneficial as primary transplantation in propensity-matched patients. However, survival is severely diminished in those retransplanted less than 90 days after primary transplantation. The utility of early retransplantation needs to be carefully weighed in light of risks., (Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Methods for direct measurement of glomerular filtration rate (GFR) are expensive and inconsistently applied across transplant centers. The Modified Diet in Renal Disease (MDRD) equation is commonly used for GFR estimation, but is inaccurate for GFRs >60 ml/min per 1.73 m(2). The Chronic Kidney Disease Epidemiology Collaboration (CKDEPI) and Wright equations have shown improved predictive capabilities in some patient populations. We compared these equations to determine which one correlates best with direct GFR measurement in lung transplant candidates., Methods: We conducted a retrospective cohort analysis of 274 lung transplant recipients. Pre-operative GFR was measured directly using a radionuclide GFR assay. Results from the MDRD, CKDEPI, Wright, and Cockroft-Gault equations were compared with direct measurement. Findings were validated using logistic regression models and receiver operating characteristic (ROC) analyses in looking at GFR as a predictor of mortality and renal function outcomes post-transplant., Results: Assessed against the radionuclide GFR measurement, CKDEPI provided the most consistent results, with low values for bias (0.78), relative standard error (0.03) and mean absolute percentage error (15.02). Greater deviation from radionuclide GFR was observed for all other equations. Pearson's correlation between radionuclide and calculated GFR was significant for all equations. Regression and ROC analyses revealed equivalent utility of the radionuclide assay and GFR equations for predicting post-transplant acute kidney injury and chronic kidney disease (p < 0.05)., Conclusions: In patients being evaluated for lung transplantation, CKDEPI correlates closely with direct radionuclide GFR measurement and equivalently predicts post-operative renal outcomes. Transplant centers could consider replacing or supplementing direct GFR measurement with less expensive, more convenient estimation by using the CKDEPI equation., (Copyright © 2014 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

Background: Mast cells have been associated with obliterative bronchiolitis (OB) in human pulmonary allografts, although their role in the development of OB remains unknown., Methods: In this study, we evaluated the role of mast cells in pulmonary allograft rejection using an orthotopic rat pulmonary allograft model that utilizes chronic aspiration of gastric fluid to reliably obtain OB. Pulmonary allograft recipients (n = 35) received chronic aspiration of gastric fluid with (n = 10) and without (n = 16) treatment with a mast cell membrane stabilizer, cromolyn sodium, or chronic aspiration with normal saline (n = 9) as a control., Results: The acute graft injury associated with long ischemic time in the model (6 hours total ischemic time; typical acute graft injury rate ~30%) was apparently blocked by cromolyn, because peri-operative mortality associated with the acute graft injury was not observed in any of the animals receiving cromolyn (p = 0.045). Further, the rats receiving cromolyn developed significantly fewer OB lesions than those treated with gastric fluid alone (p < 0.001), with a mean reduction of 46% of the airways affected., Conclusions: These findings provide impetus for further studies aimed at elucidating the effects of cromolyn and the role of mast cells in pulmonary allotransplantation., (Copyright © 2014 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

Background: The evidence behind the widely used pre-lung transplant glomerular filtration rate (GFR) cutoff of 50 mL/min per 1.73 m2 is limited. This study reviews data from a large cohort to assess outcomes associated with this historical cutoff and to estimate other possible cutoffs that might be appropriate in lung transplantation., Methods: We conducted a retrospective cohort analysis of lung recipients at a single center. Recursive partitioning and receiver operating characteristics analysis were used to estimate other potential GFR cutoffs with 1-year mortality as the outcome. Postoperative outcomes around the various cutoffs, including survival, acute kidney injury, and dialysis, were assessed using χ2, Kaplan-Meier, and Cox regression methods., Results: A total of 794 lung recipients met study inclusion criteria. Compared with 778 patients with GFR 50 mL/min per 1.73 m2 or greater at time of transplant, 16 patients with GFR below this cutoff were older and more likely to have restrictive disease. One-year mortality below the cutoff was 31.3% compared with 15.1% above the cutoff (p=0.021). Recursive partitioning estimated potential GFR cutoff values between 46 and 61 mL/min per 1.73 m2. Patients with GFR below these cutoffs were at significantly higher risk for adverse outcomes (p<0.05). Receiver operating characteristics analysis was less successful at identifying meaningful cutoff values with areas under the curve approximately 0.5., Conclusions: Study results support the practice of requiring candidate GFR 50 mL/min per 1.73 m2 or greater for lung transplantation. Future work should focus on reproducing the analysis in a larger cohort of patients including more individuals with low GFR., (Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

We hypothesized that the effect of hyperbaric oxygen (HBO) on bone formation is increased via osteogenic differentiation of bone marrow stromal cells (BMSCs), which is regulated by Wnt3a/β-catenin signaling. Our in vitro data showed that HBO increased cell proliferation, Wnt3a production, LRP6 phosphorylation, and cyclin D1 expression in osteogenically differentiated BMSCs. The mRNA and protein levels of Wnt3a, β-catenin, and Runx2 were upregulated while those of GSK-3β were downregulated after HBO treatment. The relative density ratio (phospho-protein/protein) of Akt and GSK-3β was both up-regulated while that of β-catenin was down-regulated after HBO treatment. We next investigated whether HBO affects the accumulation of β-catenin. Our Western blot analysis showed increased levels of translocated β-catenin that stimulated the expression of target genes after HBO treatment. HBO increased TCF-dependent transcription, Runx2 promoter/Luc gene activity, and the expression of osteogenic markers of BMSCs, such as alkaline phosphatase activity, type I collagen, osteocalcin, calcium, and the intensity of Alizarin Red staining. HBO dose dependently increased the bone morphogenetic protein (BMP2) and osterix production. We further demonstrated that HBO increased the expression of vacuolar-ATPases, which stimulated Wnt3a secretion from BMSCs. Finally, we showed that the beneficial effects of HBO on bone formation were related to Wnt3a/β-catenin signaling in a rabbit model by histology, mechanical testing, and immunohistochemical assays. Accordingly, we concluded that HBO increased the osteogenic differentiation of BMSCs by regulating Wnt3a secretion and signaling., (© 2013.)

Coronary artery disease (CAD) is not uncommon among lung transplant candidates. Several small, single-center series have suggested that short-term outcomes are acceptable in selected patients who undergo coronary revascularization prior to, or concomitant with, lung transplantation. Our objective was to evaluate perioperative and intermediate-term outcomes in this patient population at our institution. We performed a retrospective, observational cohort analysis of 898 lung transplant recipients between 1997 and 2010. Pediatric, multivisceral, lobar or repeat transplantations were excluded, resulting in 791 patients for comparative analysis, of which 49 (median age 62, 79.6% bilateral transplant) underwent concurrent coronary artery bypass and 38 (median age 64, 63.2% bilateral transplant) received preoperative percutaneous coronary intervention (PCI). Perioperative mortality, overall unadjusted survival and adjusted hazard ratio for cumulative risk of death were similar among both revascularization groups as well as controls. The rate of postoperative major adverse cardiac events was also similar among groups; however, concurrent coronary artery bypass was associated with longer postoperative length of stay, more time in the intensive care unit and more postoperative days requiring ventilator support. These results suggest that patients with CAD need not be excluded from lung transplantation. Preferential consideration should be given to preoperative PCI when feasible., (© Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Background: Risk factors and outcomes of bronchial stricture after lung transplantation are not well defined. An association between acute rejection and development of stricture has been suggested in small case series. We evaluated this relationship using a large national registry., Methods: All lung transplantations between April 1994 and December 2008 per the United Network for Organ Sharing (UNOS) database were analyzed. Generalized linear models were used to determine the association between early rejection and development of stricture after adjusting for potential confounders. The association of stricture with postoperative lung function and overall survival was also evaluated., Results: Nine thousand three hundred thirty-five patients were included for analysis. The incidence of stricture was 11.5% (1,077/9,335), with no significant change in incidence during the study period (P=0.13). Early rejection was associated with a significantly greater incidence of stricture (adjusted odds ratio [AOR], 1.40; 95% confidence interval [CI], 1.22-1.61; p<0.0001). Male sex, restrictive lung disease, and pretransplantation requirement for hospitalization were also associated with stricture. Those who experienced stricture had a lower postoperative peak percent predicted forced expiratory volume at 1 second (FEV1) (median 74% versus 86% for bilateral transplants only; p<0.0001), shorter unadjusted survival (median 6.09 versus 6.82 years; p<0.001) and increased risk of death after adjusting for potential confounders (adjusted hazard ratio 1.13; 95% CI, 1.03-1.23; p=0.007)., Conclusions: Early rejection is associated with an increased incidence of stricture. Recipients with stricture demonstrate worse postoperative lung function and survival. Prospective studies may be warranted to further assess causality and the potential for coordinated rejection and stricture surveillance strategies to improve postoperative outcomes., (Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

A multi-compartment physiologically based pharmacokinetic (PBPK) model was developed to describe the behavior of Cr(III) and Cr(VI) in humans. Compartments were included for gastrointestinal lumen, oral mucosa, stomach, small intestinal tissue, blood, liver, kidney, bone, and a combined compartment for remaining tissues. As chronic exposure to high concentrations of Cr(VI) in drinking water cause small intestinal cancer in mice, the toxicokinetics of Cr(VI) in the upper gastrointestinal tract of rodents and humans are important for assessing internal tissue dose in risk assessment. Fasted human stomach fluid was collected and ex vivo Cr(VI) reduction studies were conducted and used to characterize reduction of Cr(VI) in human stomach fluid as a mixed second-order, pH-dependent process. For model development, toxicokinetic data for total chromium in human tissues and excreta were identified from the published literature. Overall, the PBPK model provides a good description of chromium toxicokinetics and is consistent with the available total chromium data from Cr(III) and Cr(VI) exposures in typical humans (i.e., model predictions are within a factor of three for approximately 86% of available data). By accounting for key species differences, sources of saturable toxicokinetics, and sources of uncertainty and variation, the rodent and human PBPK models can provide a robust characterization of toxicokinetics in the target tissue of the small intestine allowing for improved health risk assessment of human populations exposed to environmentally-relevant concentrations., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Aspiration of gastric fluid into the lung mediates the development of obliterative bronchiolitis (OB) in orthotopic WKY-to-F344 rat pulmonary transplants that have been subjected to immunosuppression with cyclosporine. However, the contribution of ischemic time to this process remains unknown. In this study, the effect of long (n = 16) and short (n = 12) ischemic times (average of 6 h and of 73 min, respectively) on rat lung transplants receiving aspiration of gastric fluid was assessed. Long ischemic times (LIT) led to significantly (p < 0.05) greater development of OB (ratio of OB lesions/total airways = 0.45 ± 0.07, mean ± standard error) compared to short ischemic times (ratio = 0.19 ± 0.05). However, the development of OB was dependent on aspiration, as controls receiving aspiration with normal saline showed little development of OB, regardless of ischemic time (p < 0.05). These data suggest that LIT, while insufficient by itself to lead to OB, works synergistically with aspiration of gastric fluid to exacerbate the development of OB., (© Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Background: Previous reports demonstrate that 1-year survival is severely compromised in patients with severe primary graft dysfunction (PGD) after lung transplantation. We examined if advances in extracorporeal membrane oxygenation (ECMO) support, including polymethylpentene oxygenators and reliance on venovenous (VV) ECMO have improved outcomes in patients with severe PGD after lung transplantation., Methods: The analysis included data prospectively collected on all single-lung or double-lung transplants between November 2001 and December 2009. Heart-lung transplants were excluded. Comparisons were made between recipients who did and did not require ECMO for PGD after transplant., Results: Since November 2001, when VV ECMO became the routine treatment for severe PGD after transplant at our center, 28 of 498 patients (6%) have required VV ECMO support. Successful weaning occurred in 27 of 28 (96%). Support was withdrawn for 1 patient with irreversible neurologic injury. Survival was substantially better than in previous reports: 30 days, 82%; 1 year, 64%; and 5 years, 49%. Freedom from bronchiolitis obliterans syndrome was 88% in the ECMO survivors at 3 years, but maximum allograft function was considerably worse than in transplant recipients not requiring ECMO (peak forced expiratory volume in 1 second: 58% in ECMO vs 83% in non-ECMO, p=0.001)., Conclusions: Advances in ECMO technology, particularly VV ECMO, have greatly improved the ability to support patients with severe PGD after lung transplantation. VV ECMO is an important tool in the armamentarium of any lung transplant program to optimize patient outcomes; however, strategies to improve lung allograft function in patients experiencing severe PGD are still needed., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Gastroesophageal reflux disease (GERD) in lung recipients is associated with decreased survival and attenuated allograft function. This study evaluates fundoplication in preventing GERD-related allograft dysfunction., Methods: Prospectively collected data on patients who underwent transplantation between January 2001 and August 2009 were included. Lung transplant candidates underwent esophageal pH probe testing before transplantation and surveillance spirometry evaluation after transplantation. Bilateral lung transplant recipients who had pretransplant pH probe testing and posttransplant 1-year forced expiratory volume in the first second of expiration (FEV1) data were included for analysis., Results: Of 297 patients who met study criteria, 222 (75%) had an abnormal pH probe study before or early after transplantation and 157 (53%) had a fundoplication performed within the first year after transplantation. Patients with total proximal acid contact times greater than 1.2% or total distal acid contact times greater than 7.0% demonstrated an absolute decrease of 9.4% (±4.6) or 12.0% (±5.4) in their respective mean 1-year FEV1 values. Patients with abnormal acid contact times who did not undergo fundoplication had considerably worse predicted peak and 1-year FEV1 results compared with recipients receiving fundoplication (peak percent predicted=75% vs. 84%; p=0.004 and 1-year percent predicted=68% vs. 77%; p=0.003, respectively)., Conclusions: Lung transplant recipients with abnormal esophageal pH studies attain a lower peak allograft function as well as a diminished 1-year FEV1 after transplantation. However a strategy of early fundoplication in these recipients appears to preserve lung allograft function., (Copyright © 2011 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Lung transplantation, definitive therapy for end-stage lung disease, is limited long-term by allograft dysfunction including bronchiolitis obliterans syndrome (BOS). Few modifiable risk factors for pulmonary transplant-related mortality are recognized. However, oropharyngeal dysphagia frequently occurs after thoracic surgical procedures, including lung transplantation, and increases morbidity. We evaluated the impact of oropharyngeal dysphagia on survival and BOS after lung transplantation., Methods: A total of 263 consecutive lung transplant patients were reviewed. Each underwent clinical swallowing evaluation early after surgery; 149 patients underwent additional fiberoptic or videofluoroscopic swallowing evaluation (SE). Results of SE were correlated with BOS, defined by accepted criteria, and mortality using Kaplan-Meier survival curves. Cox proportional hazard modeling assessed preoperative and postoperative variables associated with development of BOS and mortality., Results: Mean follow-up was 920 ± 560 days. The SE identified tracheal aspiration and (or) laryngeal penetration in 70.5%. Preoperative tobacco abuse, gastroesophageal reflux, and cardiopulmonary bypass independently predicted oropharyngeal dysphagia. Peak FEV(1) (forced expiratory volume in the first second of expiration) alone independently predicted BOS (hazard ratio 0.98; confidence interval 0.975 to 0.992, p < 0.0001); oropharyngeal dysphagia was not associated with BOS. Independent predictors of mortality by multivariable analysis were ventilator dependence (p = 0.038) and peak FEV(1) (p < 0.0001); normal SE was associated with improved survival (hazard ratio 0.13; confidence interval 0.03 to 0.54, p = 0.03)., Conclusions: Oropharyngeal dysphagia, often overlooked on clinical examination, is common after lung transplantation. Normal deglutition may improve survival after lung transplantation, but oropharyngeal dysphagia does not independently affect BOS. Institution of protocols aimed at identifying previously unrecognized dysphagia may improve results of pulmonary transplantation., (Copyright © 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Asthma occurs in more than 5% of the population in industrialized countries and is now characterized as a chronic inflammatory disease. The chronic aspiration of gastric fluid is considered by many investigators to be a primary inflammatory factor exacerbating or predisposing patients to asthma, with more than 50 medical papers per year linking asthma with gastroesophageal reflux disease (GERD), which can lead to aspiration events. However, the mechanisms involved in the inflammatory effects caused by gastric-fluid aspiration are not clear at the present time. The role of macrophages in the pathogenesis of disease seems likely given the involvement of those cells in a variety of chronic inflammatory diseases. To investigate the potential role of gastric fluid and the mechanisms potentially underlying chronic aspiration-associated pathogenesis, we examined the activation of murine macrophages (Raw 264.7 cell line) with gastric fluid. Inflammatory cytokine production and activation of the NF-kappaB signaling pathway were observed. Toll-like receptor (TLR)-4-dependent activation was observed under some conditions, indicating that bacterial components within the gastric fluid are involved in macrophage activation. Matrix metalloproteinase-9 (MMP-9) expression by macrophages was enhanced by gastric fluid, suggesting a potential mechanism by which remodeling of airways might be induced by gastric-fluid aspiration., (2009 Elsevier GmbH. All rights reserved.)

HIV infection remains a worldwide threat. HIV-1 transactivator protein Tat is one of the retroviral proteins identified as a key immunomodulator in AIDS pathogenesis. Although the primary function of Tat is to regulate HIV-1 replication in the infected cell, it also dysregulates cytokine production resulting in perturbation of the host immune response and enhancement of the retrovirus survival. Because interferon-gamma (IFNgamma) is a pleiotropic cytokine with potent antiviral and immunoregulatory effects, we investigated whether Tat interferes with the IFNgamma signal transduction in primary monocytes. We demonstrated that Tat impaired the IFNgamma-receptor signaling pathway at the level of STAT1 activation, possibly via Tat-dependent induction of suppressor of cytokine signaling-2 (SOCS-2) activity. We delineated the inhibitory role of SOCS-2 in IFNgamma signaling pathway by overexpression of exogenous SOCS-2 in HEK293 cell. The results showed that SOCS-2 suppressed the IFNgamma-activated STAT1 phosphorylation and consequent IFNgamma-regulated transcription of specific genes. To confirm the role of SOCS2 in the Tat-induced process, we demonstrated that SOCS-2 siRNA in human blood monocytes abrogated the Tat-dependent inhibition of IFNgamma signaling. Our data suggested a possible mechanism implicating the role of SOCS-2 in mediating HIV-1-induced immune evasion and dysregulation of IFNgamma signaling in primary human monocytes.

Background: The development of laser-assisted extraction techniques for chronically implanted pacemaker and defibrillator leads has reduced the need for open surgical removal. Reports of the mortality from laser-assisted extraction range from 1.9% to 3.4%. The purpose of this study was to determine the rate of major cardiovascular injury and emphasize the need for cardiothoracic surgical participation in this procedure., Methods: A retrospective cohort study was performed of 112 consecutive laser-assisted lead extractions at a single university medical center during a 6-year period. Patient and lead characteristics were analyzed as well as indications, outcomes, and major complications., Results: Successful lead extraction was accomplished in 103 (92%) of the 112 patients. Elective sternotomy after failure of laser-assisted lead removal was successfully performed in 4 patients. Emergent surgical intervention was required in 4 patients for caval perforation (n = 2), subclavian vein injury (n = 1), or right atrial injury (n = 1). Three of the 4 patients requiring emergent intervention died, for an overall series mortality of 2.6%. In July of 2006, a policy of cardiothoracic surgeon presence during the laser-assisted extraction was instituted. Since that time, there has been one emergent sternotomy and one elective sternotomy for lead removal with no procedure-related deaths., Conclusions: Despite recent advances in laser technology for the removal of pacemaker and defibrillator leads, the potential for major cardiovascular injury and death remains. Involvement of the cardiothoracic surgeon in both the preoperative decision-making process as well as the laser-assisted lead extraction is critical to prevent or emergently treat any major complications.

Long-term survival of a pulmonary allograft is currently hampered by obliterative bronchiolitis (OB), a form of chronic rejection that is unique to lung transplantation. While tracheobronchial aspiration from gastroesophageal reflux disease (GERD) has clinically been associated with OB, no experimental model exists to investigate this problem. Using a WKY-to-F344 rat orthotopic left lung transplant model, the effects of chronic aspiration on pulmonary allograft were evaluated. Recipients received cyclosporine with or without 8 weekly aspirations of gastric fluid into the allograft. Six (66.7%) of 9 allografts with aspiration demonstrated bronchioles with surrounding monocytic infiltrates, fibrosis and loss of normal lumen anatomy, consistent with the development of OB. In contrast, none of the allografts without aspiration (n = 10) demonstrated these findings (p = 0.002). Of the grafts examined grossly, 83% of the allografts with chronic aspiration but only 20% without aspiration appeared consolidated (p = 0.013). Aspiration was associated with increased levels of IL-1 alpha, IL-1 beta, IL-6, IL-10, TNF-alpha and TGF-beta in BAL and of IL-1 alpha, IL-4 and GM-CSF in serum. This study provides experimental evidence linking chronic aspiration to the development of OB and suggests that strategies aimed at preventing aspiration-related injuries might improve outcomes in clinical lung transplantation.

Background: Lung transplant survival is limited by the development of bronchiolitis obliterans syndrome (BOS). The strongest risk factor for BOS is acute rejection (AR). We have previously shown that rabbit anti-thymocyte globulin (RATG) induction therapy is associated with a decrease in early AR. Thus, we hypothesized that RATG induction would translate to reduced BOS and improved long-term graft survival., Methods: Forty-four lung recipients were prospectively randomized to receive conventional immunosuppression with RATG induction (RATG group) or conventional immunosuppression alone (control group). End-points included graft survival, early and total acute rejection, BOS and treatment complications., Results: There was no difference in graft survival between the groups at 8 years (RATG: 36%; control: 23%; p = 0.48). The RATG group had fewer early rejections compared with the control group (5% vs 41%; p = 0.01). However, the overall rejection incidence did not differ (RATG: 62%; control: 68%; p = 0.52). There was a trend toward a delay in BOS onset among RATG subjects compared with control subjects (2,376 days vs 1,108 days; log rank, p = 0.15). There was no difference in the incidence of infections, but the RATG group had a higher rate of malignancies., Conclusions: Our results suggest that alternative approaches to anti-thymocyte induction should be pursued to reduce BOS and prolong allograft survival.

The human vermiform ("worm-like") appendix is a 5-10cm long and 0.5-1cm wide pouch that extends from the cecum of the large bowel. The architecture of the human appendix is unique among mammals, and few mammals other than humans have an appendix at all. The function of the human appendix has long been a matter of debate, with the structure often considered to be a vestige of evolutionary development despite evidence to the contrary based on comparative primate anatomy. The appendix is thought to have some immune function based on its association with substantial lymphatic tissue, although the specific nature of that putative function is unknown. Based (a) on a recently acquired understanding of immune-mediated biofilm formation by commensal bacteria in the mammalian gut, (b) on biofilm distribution in the large bowel, (c) the association of lymphoid tissue with the appendix, (d) the potential for biofilms to protect and support colonization by commensal bacteria, and (e) on the architecture of the human bowel, we propose that the human appendix is well suited as a "safe house" for commensal bacteria, providing support for bacterial growth and potentially facilitating re-inoculation of the colon in the event that the contents of the intestinal tract are purged following exposure to a pathogen.

Despite substantial improvements in early survival after lung transplantation, refractory acute rejection (RAR) and bronchiolitis obliterans syndrome (BOS) remain major contributors to transplant-related morbidity and mortality. We have utilized alemtuzumab, a humanized anti-CD52 antibody which results in potent lymphocyte depletion, in consecutive patients with RAR (n = 12) or BOS (n = 10). All patients failed conventional treatment with methylprednisolone and antithymocyte globulin and received strict infection prophylaxis. Alemtuzumab significantly improved histological rejection scores in RAR. Total rejection grade/biopsy was 1.98 +/- 0.25 preceding alemtuzumab versus 0.33 +/- 0.14 posttreatment, p-value <0.0001 (with a similar number of biopsies/patient per respective time interval). Freedom from BOS was observed in 65% of RAR patients 2 years after alemtuzumab treatment. Although there was no statistically significant change in forced expiratory volume in 1 second (FEV1) before and after alemtuzumab treatment in patients with BOS, a stabilization or improvement in BOS grade occurred in 70% of patients. Patient survival 2 years after alemtuzumab for BOS was 69%. Despite a dramatic decline in CD4 counts in alemtuzumab-treated patients, only one patient developed a lethal infection. Thus, we provide the first evidence that alemtuzumab is a potentially useful therapy in lung transplant recipients with RAR or BOS.

Background: Gastroesophageal reflux is associated with lung transplantation (LT) and bronchiolitis obliterans syndrome, limiting allograft functional longevity. LT patients may also develop post-operative oropharyngeal dysphagia, exposing the allograft to further risk. However, the magnitude of this problem is unknown. We examined LT recipients post-operatively for swallowing disorders and correlated findings with pre- and post-operative variables., Methods: Two hundred sixty-three LT patients (January 2001 to July 2005) at a single center were retrospectively reviewed. Each underwent clinical swallowing assessment. Provocative swallowing evaluation (SE) was performed in 149 patients (Group 1); 114 patients did not receive formal SE (Group 2). SE studies were considered positive with laryngeal penetration (PEN) or tracheal aspiration (ASP) of thin liquids. Groups were compared with respect to pre-, peri- and post-operative variables using analysis of variance (ANOVA) and chi-square tests., Results: After LT, 56.7% of patients underwent post-operative SE (mean 19 +/- 20 days), most of whom (87.9%) had fiber-optic endoscopic studies. SE was positive for PEN or ASP in 70.5% (n = 105). Aspiration occurred in 63.8% (n = 67) of positive SEs; 77.6% (n = 52) of ASP assessments were clinically silent. Pre-operative gastroesophageal reflux disease (GERD) and post-operative complications, including vocal cord paresis, pleural processes, venous thromboses and severe rejection episodes, were more common among Group 1. Group 2 had a significantly reduced hospital length of stay (p = 0.004)., Conclusions: Prospective SE identified strikingly high rates of dysphagia after LT. Because many of these deficits are silent, aggressive pulmonary toilet is especially important after post-operative LT. Pre-operative SE may clarify those at increased risk for new-onset oropharyngeal dysphagia after LT.

Since the advent of various novel immunosuppressants, including tacrolimus, rapamycin, and daclixumab. expanding variations of protocols have been developed. Little evidence exists to substantially support a single agent over another. or a combination regimen protocol over another. Therefore, the principles and the goals of immunosuppression in lung transplantation recipients will remain moving targets and continue to evolve, and the use of large-scale, multi-institutional clinical trials is imperative to develop optimal immunosuppressive strategies.

The activation of human telomerase, a process regulated by the human telomerase reverse transcriptase (hTERT), is a crucial step during cellular immortalization and malignant transformation. We have reported that gambogic acid (GA), a natural product isolated from the gamboge resin of Garcinia hanburyi tree, is an effective telomerase inhibitor and thus displays potent anticancer activity both in vitro and in vivo. Here we present the direct interaction of GA with oncogene c-MYC, a ubiquitous transcription factor involved in the control of cell proliferation and differentiation, as the molecular mechanism of GA's inhibitory effect on telomerase activity. Consistent with the recently reported association between c-MYC overexpression and induction of telomerase activity, we find here that GA treatment of a human hepatoma cell line SMMC-7721 significantly reduced the expression of c-MYC in a time- and concentration-dependent manner accompanied with the down-regulation of the hTERT transcription and the ultimate reduction in telomerase activity. Our results indicate that the hTERT is a target of c-MYC activity and identify a feasible mechanism of GA's potent anticancer activity.

Background: Primary graft failure remains a significant source of mortality after lung transplantation. Extracorporeal membrane oxygenation (ECMO) provides treatment for affected recipients. We hypothesized that venovenous membrane oxygenation provides a safer alternative than venoarterial support for lung recipients suffering from primary graft failure., Methods: We conducted an analysis of 522 patients who underwent lung transplantation from April 1992 to July 2004. Twenty-three (4.5%) patients required membrane oxygenation secondary to primary graft failure unresponsive to conventional treatment. Of these recipients, 15 (65%) were treated with venoarterial, while 8 (35%) underwent venovenous membrane oxygenation., Results: Median days to initiation and duration of membrane oxygenation did not differ between groups. Eight of 15 patients (53%) from the venoarterial group were successfully weaned from life support, with one surviving greater than 45 days. This lone long-term survivor required retransplantation 4 days after initial transplant. In contrast, all venovenous patients were weaned from support, with 7 of 8 surviving greater than 30 days. The 30-day survival for venovenous recipients (88%) approximates that of all lung recipients at our center (94%, p = 0.42). Noted complications for ECMO patients included renal failure (n = 16), neurologic catastrophes (n = 8), sepsis (n = 5), and hemorrhage (n = 10). The venoarterial recipients suffered 30 of 39 total complications. Most of the complications for venovenous recipients involved renal failure, but by hospital discharge these patients demonstrated a mean creatinine of 0.9 mg/dL., Conclusions: For lung recipients with primary graft failure, venovenous membrane oxygenation provides better outcomes, with fewer complications, than venoarterial membrane oxygenation.

Doxorubicin-induced cardiomyopathy is not uncommon and may progress to end-stage heart failure. Treatment of this condition with heart transplantation, however, requires that the primary malignancy be deemed "cured." We present the case of a 55- year-old woman who had doxorubicin-induced cardiomyopathy and non-Hodgkin's lymphoma. The active status of her lymphoma precluded heart transplantation. She had end-stage heart failure and underwent the insertion of a left ventricular assist device as a destination therapy.

Mouth ulcers are one of the most common oral complaints. However, the association between oral ulceration and viruses and cytokines is uncertain. We detected the presence of human papilloma virus (HPV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus (HSV)-1, HSV-2 and human herpesvirus (HHV)-8 DNA in oral tissues by polymerase chain reaction (PCR) and Southern hybridization techniques, and quantified the serum levels of cytokines including interleukin (IL)-2, IL-4, granulocyte-macrophage colony-stimulating factor (GM-CSF), soluble Fas (sFas) and the Fas ligand (FasL) by enzyme-linked immunosorbent assay (ELISA) for 67 recurrent aphthous ulcer (RAU) patients and 72 normal individuals. Seven patient specimens were excluded from the study due to the negative PCR results for the beta-globin used as the internal control. Among the 32 (53.3%) virus-positive results from 60 patients' samples, 8 (13.3%) HPV, 4 (6.7%) HSV-1, 11 (18.3%) CMV, 9 (15.0%) EBV, and 16 (26.7%) HHV-8 samples proved to be positive. No HSV-2-positive samples were found. The percentage of single-virus infection (56.3%) was significantly greater than that of double-virus co-infection (31.3%) and the percentage of double-virus co-infection was significantly greater than the percentage of triple-virus co-infection (12.5%) (P < 0.05). In the 72 normal oral-tissue specimens, no viral DNA was detected. The mean serum cytokine level for patients was significantly (P < 0.05) greater than for controls for most of the separate age groups. The mean serum cytokine concentrations for the patient group demonstrated a diffuse pattern covering a wide range of serum concentrations, a very different result from the compact serum concentration pattern and lower mean serum cytokine concentrations revealed by the normal group. Overall association between viruses and recurrent aphthous ulceration is HHV-8 > CMV > EBV > HPV > HSV-1, regarding the frequency of prevalence (P < 0.05).

An enhanced polymerase chain reaction (PCR) assay to detect the coronavirus associated with severe acute respiratory syndrome (SARS-CoV) was developed in which a target gene pre-amplification step preceded TaqMan real-time fluorescent PCR. Clinical samples were collected from 120 patients diagnosed as suspected or probable SARS cases and analyzed by conventional PCR followed by agarose gel electrophoresis, conventional TaqMan real-time PCR, and our enhanced TaqMan real-time PCR assays. An amplicon of the size expected from SARS-CoV was obtained from 28/120 samples using the enhanced real-time PCR method. Conventional PCR and real-time PCR alone identified fewer SARS-CoV positive cases. Results were confirmed by viral culture in 3/28 cases. The limit of detection of the enhanced real-time PCR method was 10(2)-fold higher than the standard real-time PCR assay and 10(7)-fold higher than conventional PCR methods. The increased sensitivity of the assay may help control the spread of the disease during future SARS outbreaks.

The 1,3-1,4-beta-D-glucanase from Fibrobacter succinogenes (Fsbeta-glucanase) is classified as one of the family 16 glycosyl hydrolases. It hydrolyzes the glycosidic bond in the mixed-linked glucans containing beta-1,3- and beta-1,4-glycosidic linkages. We constructed a truncated form of recombinant Fsbeta-glucanase containing the catalytic domain from amino acid residues 1-258, which exhibited a higher thermal stability and enzymatic activity than the full-length enzyme. The crystal structure of the truncated Fsbeta-glucanase was solved at a resolution of 1.7A by the multiple wavelength anomalous dispersion (MAD) method using the anomalous signals from the seleno-methionine-labeled protein. The overall topology of the truncated Fsbeta-glucanase consists mainly of two eight-stranded anti-parallel beta-sheets arranged in a jellyroll beta-sandwich, similar to the fold of many glycosyl hydrolases and carbohydrate-binding modules. Sequence comparison with other bacterial glucanases showed that Fsbeta-glucanase is the only naturally occurring circularly permuted beta-glucanase with reversed sequences. Structural comparison shows that the engineered circular-permuted Bacillus enzymes are more similar to their parent enzymes with which they share approximately 70% sequence identity, than to the naturally occurring Fsbeta-glucanase of similar topology with 30% identity. This result suggests that protein structure relies more on sequence identity than topology. The high-resolution structure of Fsbeta-glucanase provides a structural rationale for the different activities obtained from a series of mutant glucanases and a basis for the development of engineered enzymes with increased activity and structural stability.

The disaccharide Gal(alpha)1-3Gal is found on more than 45 different molecules on the endothelium of porcine cells and has recently attracted considerable interest, being the major target recognized by xenoreactive antibodies. In this study, the distribution and topology of Gal(alpha)1-3Gal on porcine endothelial cells was examined to access whether some Gal(alpha)1-3Gal-containing molecules might be preferentially recognized by antibodies binding to Gal(alpha)1-3Gal. Thirteen percent of the Gal(alpha)1-3Gal was found on glycolipid and 87% on glycoproteins. Of all the glycoproteins and glycolipids containing Gal(alpha)1-3Gal, two molecules, fibronectin and the integrin beta1 subunit, were most intensely labeled by galactose oxidase, suggesting that these molecules may be preferentially exposed on the apical surface of the endothelium. Binding of anti-Gal(alpha)1-3Gal antibodies to endothelial cell surfaces significantly diminished labeling of fibronectin and the integrin beta1 subunit by galactose oxidase, indicating that these glycoproteins are targets for the antibodies when binding to intact porcine cells.

Purpose: Reproductive factors are often evaluated in epidemiologic interview studies as risk factors for diseases in women. Similarly, childhood social class has been implicated in the etiology of several diseases. Nevertheless, questions related to these factors have not been thoroughly evaluated for test-retest reliability. This research measured the test-retest reliability of reproductive and childhood social class variables, and determined whether reliability differed by case-control status, age, educational level, time between interviews, and interviewer-rated quality of the interview., Methods: Subjects were participants in a population-based case-control in-person interview study of Hodgkin's disease in northern California women. Twenty-four cases and 22 controls were reinterviewed by telephone between 1992 and 1995, with an average interval of 8 months between interviews. Reliability was assessed using kappa or intraclass correlation coefficients; mean reliability coefficients and 95% confidence intervals (CIs) were estimated using the bootstrap method., Results: Reliability was excellent for all variables (reliability coefficients between 0.76 and 0.96) and did not differ by case-control status (mean reliability = 0.82 for cases and 0.84 for controls), age (mean reliability = 0.85 for age < 40 and 0.82 for age > or = 40), time between interviews (mean reliability = 0.75 for 0-5 months, 0.88 for 6-11 months, and 0.87 for 1 year or more), or interviewer-rated quality of the validity of the original responses (mean reliability = 0.93 for "not too confident" and 0.83 for "confident"). However, reliability was consistently lower among less educated women (mean reliability = 0.56 for high school or less and 0.88 for more than high school), a finding consistent with results of prior studies., Conclusions: These results indicate that questions about reproductive experience and childhood social class posed in in-person interviews can be answered reliably. However, inclusion of subjects at lower socioeconomic status may result in lower reliability for some interview responses.

Xenoreactive natural antibodies in humans and higher primates are directed predominantly at Gal alpha 1-3Gal. These antibodies are thought to initiate hyperacute rejection of porcine organ xenografts. The contribution of anti-Gal alpha 1-3Gal antibodies to the xenoractive natural antibody repertoire and to the initiation of hyperacute rejection was tested in a pig-to-baboon cardiac xenograft model. Anti-Gal alpha 1-3Gal antibodies were depleted from baboons by extracorporeal absorption of anti-Gal alpha 1-3Gal antibodies from plasma using columns with a matrix bearing Gal alpha 1-3Galb1-4GlcNAc. Specific removal of anti-Gal alpha 1-3Gal antibodies was achieved prior to transplantation as demonstrated by immunoassay. Porcine hearts were then transplanted into these baboons and the outcome of the transplants was analysed. Immunofluorescence revealed little deposition of baboon antibodies in the grafts. The porcine hearts did not undergo hyperacute rejection even though complement activity was approximately 90% of baseline at the time of transplantation. These findings demonstrate that anti-Gal alpha 1-3Gal antibodies constitute a major fraction of xenoreactive natural antibodies in primate blood and that these antibodies contribute significantly to the pathogenesis of hyperacute xenograft rejection.

The sterol regulatory element binding proteins (SREBPs) are central regulators of lipid homeostasis in mammalian cells. Their activity is controlled by a sterol-regulated two-step proteolytic process that releases the nuclear targeted amino-terminal domain from the membrane anchored carboxyl-terminal remnant. This ensures that transcriptional stimulation of the appropriate genes occurs only when increased intracellular sterol accumulation is required. Gene targets for SREBP encode key proteins of cholesterol metabolism as well as essential proteins of fatty acid biosynthesis, providing a mechanism for coordinate control of these two major lipid pathways when sterols and fatty acids need to accumulate together. However, the regulatory mechanism must provide a way to uncouple these two pathways to allow separate regulation when sterol or fat levels need to increase independently of each other. We compared the similarities and differences for how SREBP activates the promoter for the low density lipoprotein (LDL) receptor, which is the key protein involved in cholesterol uptake, relative to how it activates promoters for acetyl coenzyme A carboxylase (ACC) and fatty acid synthase (FAS), which are both key enzymes of fatty acid biosynthesis. In the current studies we show there are two distinct sites for SREBP binding that control activation of the ACC PII promoter whereas previous work has shown there is only a single SREBP site in the LDL receptor. Additionally, disruption of either ACC site results in a total loss in promoter function and a severe decrease in SREBP binding even to the neighboring unaltered site. Thus, the two sites are equally important and dependent on one another for optimal function. This is in contrast to the FAS promoter where SREBP binds to two adjacent sites independently and the one located closer to the binding site for the Sp1 co-regulator is more critical for sterol regulation and activation by SREBP over-expression.

We have studied the effects of nitrous oxide on cerebral blood flow (CBF), cerebral blood flow velocity (CBFV) and intracranial pressure (ICP) during isoflurane-induced hypotension in 10 pigs. CBF was measured using laser Doppler flowmetry, CBFV in the right middle cerebral artery was calculated using Doppler ultrasound and ICP was measured using an extradural ICP monitor. Each animal was studied under four conditions, examined sequentially: (i) mean intra-arterial pressure (MAP) 85 mm Hg, maintained with isoflurane, (ii) MAP 50-55 mm Hg, induced by isoflurane only, (iii) MAP 85 mm Hg, maintained with isoflurane and 50% nitrous oxide, and (iv) MAP 50-55 mm Hg, induced by isoflurane and 50% nitrous oxide. No significant differences were noted between conditions with respect to ICP. There was a significant difference in CBF during condition (ii) compared with (i) (mean 75(SD 21) vs 100(0)%) and during condition (iv) compared with (iii) (90(26) vs 109(13)%). Animals under condition (iv) exhibited a 20% reduction in CBFV compared with those under condition (iii) (57 vs 69 cm s-1). For animals under normotensive conditions, addition of nitrous oxide to isoflurane resulted in a 16% increase in CBFV (69 vs 60 cm s-1). Comparing isoflurane-induced hypotension ((ii) vs (iv)), there was no statistical difference in either CBF or CBFV on addition of 50% nitrous oxide. The correlation between changes in CBF and CBFV was not significant. We conclude that the use of nitrous oxide during isoflurane-induced hypotension has no significant effect on CBF, CBFV or ICP compared with the use of isoflurane alone.

EGF-induced hydrolysis of phosphatidylinositol 4, 5, biphosphate was compared in A431 cells with respect to their growth response to EGF. A431 cells which express 4- to 5-fold more EGF receptors than A431-4 cells were growth inhibited, while A431-4 cells were growth stimulated by EGF within the same dose range. Treatment of A431 cells with EGF resulted in a 2-fold increase in cellular IP3 levels and the effect in A431-4 cells was not as obvious. In the presence of tyrosine kinase inhibitor coumaric acid (0.2 approximately 2 microM), A431 cell growth was stimulated, rather than inhibited, by EGF in a dose-dependent manner. In contrast, the stimulation of A431-4 cell growth by EGF was reduced under the same conditions. Furthermore, in the presence of coumaric acid (up to 0.5 microM), EGF-induced production of inositol phosphates in A431 cells was not obviously affected. Taken together, the results suggest that EGF-induced growth inhibition of A431 cells may be due to a quantitative changes of EGF-receptor tyrosine kinase activity in areas other than the recruitment and activation of phosphatidylinositol-specific phospholipase C gamma.

The presence of Chlamydia trachomatis-related deoxyribonucleic acid sequences in endocervical specimens of 317 women was analyzed by deoxyribonucleic acid hybridization techniques with deoxyribonucleic acid from C. trachomatis used as probes. Samples from 56 of 172 high-risk patients (32.6%) and 16 of 145 low-risk patients (11.0%) contained C. trachomatis-related deoxyribonucleic acid sequences. Direct detection of chlamydial antigen with enzyme-linked immunoassay on the same patients yielded positive rates of 26.3% and 7.3% for the high- and low-risk patients, respectively. C. trachomatis culture confirmed 86.3% of deoxyribonucleic acid-positive results and 84.0% of antigen-positive results. The overall sensitivities of chlamydial deoxyribonucleic acid and antigen assays were 91.7% and 68.8%, respectively, whereas the specificities were 95.3% and 94.7%. Results also suggested that the test of the C. trachomatis deoxyribonucleic acid correlated better with the female urogenital chlamydial infections than did the antigen test of C. trachomatis. The combined results of higher sensitivity in detecting the microorganism and better correlation with disease activity may make the deoxyribonucleic acid hybridization test a useful tool for the early and accurate diagnosis of C. trachomatis infections in female patients.