Effect of Early vs Late Inguinal Hernia Repair on Serious Adverse Event Rates in Preterm Infants: A Randomized Clinical Trial.

Importance: Inguinal hernia repair in preterm infants is common and is associated with considerable morbidity. Whether the inguinal hernia should be repaired prior to or after discharge from the neonatal intensive care unit is controversial. Objective: To evaluate the safety of early vs late surgical repair for preterm infants with an inguinal hernia. Design, Setting, and Participants: A multicenter randomized clinical trial including preterm infants with inguinal hernia diagnosed during initial hospitalization was conducted between September 2013 and April 2021 at 39 US hospitals. Follow-up was completed on January 3, 2023. Interventions: In the early repair strategy, infants underwent inguinal hernia repair before neonatal intensive care unit discharge. In the late repair strategy, hernia repair was planned after discharge from the neonatal intensive care unit and when the infants were older than 55 weeks' postmenstrual age. Main Outcomes and Measures: The primary outcome was occurrence of any prespecified serious adverse event during the 10-month observation period (determined by a blinded adjudication committee). The secondary outcomes included the total number of days in the hospital during the 10-month observation period. Results: Among the 338 randomized infants (172 in the early repair group and 166 in the late repair group), 320 underwent operative repair (86% were male; 2% were Asian, 30% were Black, 16% were Hispanic, 59% were White, and race and ethnicity were unknown in 9% and 4%, respectively; the mean gestational age at birth was 26.6 weeks [SD, 2.8 weeks]; the mean postnatal age at enrollment was 12 weeks [SD, 5 weeks]). Among 308 infants (91%) with complete data (159 in the early repair group and 149 in the late repair group), 44 (28%) in the early repair group vs 27 (18%) in the late repair group had at least 1 serious adverse event (risk difference, -7.9% [95% credible interval, -16.9% to 0%]; 97% bayesian posterior probability of benefit with late repair). The median number of days in the hospital during the 10-month observation period was 19.0 days (IQR, 9.8 to 35.0 days) in the early repair group vs 16.0 days (IQR, 7.0 to 38.0 days) in the late repair group (82% posterior probability of benefit with late repair). In the prespecified subgroup analyses, the probability that late repair reduced the number of infants with at least 1 serious adverse event was higher in infants with a gestational age younger than 28 weeks and in those with bronchopulmonary dysplasia (99% probability of benefit in each subgroup). Conclusions and Relevance: Among preterm infants with inguinal hernia, the late repair strategy resulted in fewer infants having at least 1 serious adverse event. These findings support delaying inguinal hernia repair until after initial discharge from the neonatal intensive care unit. Trial Registration: ClinicalTrials.gov Identifier: NCT01678638.

Primary resistance to integrase strand-transfer inhibitors in Europe.

OBJECTIVES: The objective of this study was to define the natural genotypic variation of the HIV-1 integrase gene across Europe for epidemiological surveillance of integrase strand-transfer inhibitor (InSTI) resistance. METHODS: This was a multicentre, cross-sectional study within the European SPREAD HIV resistance surveillance programme. A representative set of 300 samples was selected from 1950 naive HIV-positive subjects newly diagnosed in 2006-07. The prevalence of InSTI resistance was evaluated using quality-controlled baseline population sequencing of integrase. Signature raltegravir, elvitegravir and dolutegravir resistance mutations were defined according to the IAS-USA 2014 list. In addition, all integrase substitutions relative to HXB2 were identified, including those with a Stanford HIVdb score ≥ 10 to at least one InSTI. To rule out circulation of minority InSTI-resistant HIV, 65 samples were selected for 454 integrase sequencing. RESULTS: For the population sequencing analysis, 278 samples were retrieved and successfully analysed. No signature resistance mutations to any of the InSTIs were detected. Eleven (4%) subjects had mutations at resistance-associated positions with an HIVdb score ≥ 10. Of the 56 samples successfully analysed with 454 sequencing, no InSTI signature mutations were detected, whereas integrase substitutions with an HIVdb score ≥ 10 were found in 8 (14.3%) individuals. CONCLUSIONS: No signature InSTI-resistant variants were circulating in Europe before the introduction of InSTIs. However, polymorphisms contributing to InSTI resistance were not rare. As InSTI use becomes more widespread, continuous surveillance of primary InSTI resistance is warranted. These data will be key to modelling the kinetics of InSTI resistance transmission in Europe in the coming years.

Screening and Prophylaxis for Venous Thromboembolism in Pediatric Surgery: A Systematic Review.

OBJECTIVE: The American Pediatric Surgical Association Outcomes and Evidence-Based Practice Committee conducted a systematic review to describe the epidemiology of venous thromboembolism (VTE) in pediatric surgical and trauma patients and develop recommendations for screening and prophylaxis. METHODS: The Medline (Ovid), Embase, Cochrane, and Web of Science databases were queried from January 2000 through December 2021. Search terms addressed the following topics: incidence, ultrasound screening, and mechanical and pharmacologic prophylaxis. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines were followed. Consensus recommendations were derived based on the best available literature. RESULTS: One hundred twenty-four studies were included. The incidence of VTE in pediatric surgical populations is 0.29% (Range = 0.1%-0.48%) and directly correlates with surgery type, transfusion, prolonged anesthesia, malignancy, congenital heart disease, inflammatory bowel disease, infection, and female sex. The incidence of VTE in pediatric trauma populations is 0.25% (Range = 0.1%-0.8%) and directly correlates with injury severity, major surgery, central line placement, body mass index, spinal cord injury, and length-of-stay. Routine ultrasound screening for VTE is not recommended. Consider sequential compression devices in at-risk nonmobile, pediatric surgical patients when an appropriate sized device is available. Consider mechanical prophylaxis alone or with pharmacologic prophylaxis in adolescents >15 y and post-pubertal children <15 y with injury severity scores >25. When utilizing pharmacologic prophylaxis, low molecular weight heparin is superior to unfractionated heparin. CONCLUSIONS: While VTE remains an infrequent complication in children, consideration of mechanical and pharmacologic prophylaxis is appropriate in certain populations. TYPE OF STUDY: Systematic Review of level 2-4 studies. LEVEL OF EVIDENCE: Level 3-4.

A Review of the Use of Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Malignancy in Pediatric Patients.

Hyperthermic intraperitoneal chemotherapy (HIPEC) can directly target microscopic peritoneal disease, has achieved regular consideration in the treatment of several adult cancer types, and is more recently being studied in pediatrics. This review paper provides an overview of the use of this modality in pediatrics in order to identify medication choice, discuss post-operative morbidity and mortality, and evaluate impact on overall survival. Four databases were searched including Scopus, PubMed, Embase, and CINAHL and ultimately 37 papers documenting the use of this modality comprising 264 pediatric patients were included. Malignancies treated include desmoplastic small round cell tumor, rhabdomyosarcoma, angiosarcoma, colorectal carcinoma, and mesothelioma, with several rarer tumor types. Cisplatin was the most commonly used drug for HIPEC at varying concentrations for 30-90 min in duration at temperatures of approximately 41-42 °C. Reported toxicities were generally self-limited and there was no post-operative mortality. The impact on overall survival versus systemic chemotherapy and debulking surgery is uncertain due to lack of clinical trials and very small sample size across tumor subsets and the overall pediatric population. The relationship between degree of tumor burden and extent of surgical debulking needs to be further clarified. Future directions include prospective clinical trials, establishment of patient databases to facilitate standardization of HIPEC in pediatric patients, and additional approaches to optimize HIPEC.

Ruptured abdominal aortic aneurysm in an 11-year-old with multiple peripheral artery aneurysms.

Pediatric abdominal aortic aneurysms (AAAs) are rarely encountered in clinical practice. The combination of a pediatric AAA in a patient with multiple peripheral artery aneurysms is even more rare. We report the management of an 11-year-old boy who presented with a ruptured AAA who also had multiple peripheral arterial aneurysms. Infectious, genetic, and inflammatory workup was negative, classifying this aneurysm as congenital.

Timing of the definitive procedure and ileostomy closure for total colonic aganglionosis HD: Systematic review.

AIM: To establish the cogency of recommendations for the appropriate age for pull-through and ileostomy closure in Total Colonic Aganglionosis-Hirschsprung Disease's (TCA-HD). METHOD: Medline, PubMed, Cochrane, and the ClinicalKey databases were searched without date restriction. The studies that reported TCA-HD cases were evaluated for the number of cases, age at the definitive procedure, age at the ileostomy closure, reported complications, and the type of procedure. Perianal excoriation and diaper rash rates were analyzed using SPSS software, with p < 0.05 considered significant. RESULTS: Twenty-five studies mentioned TCA-HD findings between 1968 and 2019. The total number of patients who had definitive surgery was 218. Analysis showed no correlation between development of diaper rash and the age of the patient at the time of the definitive surgery or ileostomy closure. Studies scored between six and nine of nine possible stars on the NOS scoring system. CONCLUSION: There is no correlation between age of surgery and postoperative diaper rash. Delaying the definitive procedure or ileostomy closure for TCA-HD has limited support on a review of current studies. The perianal excoriation/diaper rash is not reported in the literature at a high enough frequency to warrant keeping a diverting ileostomy until toilet trained of urine. TYPE OF STUDY: Systematic review and meta-analysis. Levels of evidence IV.

Retroperitoneoscopic resection of a T11-L2 right-sided ganglioneuroma.

Paraspinal tumors arising from the sympathetic chain include those on the ganglioneuroma-neuroblastoma spectrum. Accurate diagnosis often requires excision owing to the histopathologic heterogeneity of these tumors and the risk of false negative biopsy results. Choice of approach is dictated by location and extirpation is usually amenable to minimally invasive techniques. We present a patient whose paraspinal tumor included the T11-L2 vertebral body levels and was removed using a retroperitoneoscopic approach. This approach is rarely considered in pediatric general surgery and afforded a useful alternative to thoracoscopy or laparoscopy.

Feasibility and Safety of Intraoperative Colonoscopy after Segmental Colectomy and Primary Anastomosis.

Patients presenting with near-obstructing colon lesions requiring segmental colectomy may benefit from intraoperative colonoscopy (IOC) after primary anastomosis for a more timely and accurate diagnosis of synchronous lesions. The aim of this study is to demonstrate the feasibility and safety of this technique. A retrospective cohort study of patients undergoing single-stage segmental colectomy and anastomosis at a single tertiary care institution from 2011 to 2013 was performed. One Hundred and sixty-eight consecutive patients underwent segmental colectomy and primary anastomosis of which 78 (46%) were unable to receive preoperative colonoscopy (POC) because of near-obstructing lesions and received IOC after the anastomosis. IOC detected synchronous adenomatous polyps in 24.4 per cent, diverticular disease in 19 per cent, and colitis/proctitis in 2.5 per cent. The IOC group was not significantly different from the POC group with regard to overall morbidity (31% vs 39% P = 0.45), anastomotic leakage (1.3% vs 0%, P = 0.46), or wound infection (5.1% vs 1.1%, P = 0.18). Operation time was 19 minutes longer in the intraoperative group, but overall length of hospital stay was not significantly different (6.4 ± 2.9 days vs 7.3 ± 4.6 days). In patients unable to receive POC because of partial obstruction, IOC after primary anastomosis is both feasible and safe for detecting proximal synchronous lesions.

Analysis of 334 Cases of Pediatric Esophageal Foreign Body Removal Suggests that Traditional Methods Have Similar Outcomes Whereas a Magnetic Tip Orogastric Tube Appears to Be an Effective, Efficient, and Safe Technique for Disc Battery Removal.

Procedures and outcomes for pediatric esophageal foreign body removal were analyzed. Traditional methods of battery removal were compared with a magnetic tip orogastric tube (MtOGT). A single institution retrospective review from 1997 to 2014 of pediatric patients with esophageal foreign bodies was performed. Balloon extraction with fluoroscopy (performed in 173 patients with 91% success), flexible endoscopy (92% success in 102 patients), and rigid esophagoscopy (95% in 38 patients) had excellent success rates. A MtOGT had 100 per cent success in six disc battery patients, when other methods were more likely to fail, and was the fastest. Power analysis suggested 20 patients in the MtOGT group would be needed for significant savings in procedural time. Thirty-two per cent of all foreign bodies and 95 per cent of batteries had complications (P = 0.002) because of the foreign body. Overall, 1.2 per cent had severe complications, whereas 10 per cent of batteries had severe complications (P = 0.04). Each technique if applied appropriately can be a reasonable option for esophageal foreign body removal. Magnetic tip orogastric tubes used to extract ferromagnetic objects like disc batteries had the shortest procedure time and highest success rate although it was not statistically significant. Disc batteries require emergent removal and have a significant complication rate.

Predictive modelling of dispersion controlled reactive plumes at the laboratory-scale.

A model-based interpretation of laboratory-scale experimental data is presented. Hydrolysis experiments carried out using thin glass tanks filled with glass beads to construct a hypothetical and inert, homogeneous porous medium were analysed using a 2D numerical model. A new empirical formula, based upon results for non-reactive (tracer) experiments is used to calculate transversal dispersivity values for a range of grain sizes and any flow velocities. Combined with effective diffusion coefficients calculated from Stokes-Einstein type equations, plume lengths arising from mixing between two solutes can be predicted accurately using numerical modelling techniques. Moreover, pH and ion concentration profiles lateral to the direction of flow of the mixing species can be determined at any given point downstream, without the need for result fitting. In our case, this approach does not lead to overpredictions of lateral mixing, as previously reported when using parameters derived from non-reactive tracer experiments to describe reactive solute transport. The theory is based on the assumption of medium homogeneity.

Mitochondrial function in hypoxic ischemic injury and influence of aging.

Mitochondria are a major target in hypoxic/ischemic injury. Mitochondrial impairment increases with age leading to dysregulation of molecular pathways linked to mitochondria. The perturbation of mitochondrial homeostasis and cellular energetics worsens outcome following hypoxic-ischemic insults in elderly individuals. In response to acute injury conditions, cellular machinery relies on rapid adaptations by modulating posttranslational modifications. Therefore, post-translational regulation of molecular mediators such as hypoxia-inducible factor 1α (HIF-1α), peroxisome proliferator-activated receptor γ coactivator α (PGC-1α), c-MYC, SIRT1 and AMPK play a critical role in the control of the glycolytic-mitochondrial energy axis in response to hypoxic-ischemic conditions. The deficiency of oxygen and nutrients leads to decreased energetic reliance on mitochondria, promoting glycolysis. The combination of pseudohypoxia, declining autophagy, and dysregulation of stress responses with aging adds to impaired host response to hypoxic-ischemic injury. Furthermore, intermitochondrial signal propagation and tissue wide oscillations in mitochondrial metabolism in response to oxidative stress are emerging as vital to cellular energetics. Recently reported intercellular transport of mitochondria through tunneling nanotubes also play a role in the response to and treatments for ischemic injury. In this review we attempt to provide an overview of some of the molecular mechanisms and potential therapies involved in the alteration of cellular energetics with aging and injury with a neurobiological perspective.

Outcomes following routine antithrombin III replacement during neonatal extracorporeal membrane oxygenation.

BACKGROUND: We sought to examine the effect of routine antithrombin III (AT3) infusion on hemorrhagic and thrombotic complications, blood product utilization, and circuit lifespan in neonatal extracorporeal membrane oxygenation (ECMO). METHODS: We performed a retrospective cohort study of 162 infants placed on ECMO for hypoxic respiratory failure. Infants requiring ECMO for primary cardiac support were excluded. Demographic data, time on ECMO, blood product usage, coagulation profile, and complications were compared between 90 control patients and 72 patients treated with AT3. RESULTS: Infants receiving AT3 during ECMO had less thrombotic and similar bleeding complications as compared to infants receiving standard anticoagulation therapy. Total blood product infusion during ECMO was decreased (54.7±20.1 vs. 67.4±34.9mL/kg per day, p=0.001) in infants receiving AT3 during ECMO. Tighter control of activated clotting time and higher serum heparin anti-Xa levels were observed in the AT3 cohort during the first days of ECMO support. 1st ECMO circuit lifespan did not differ between groups. CONCLUSIONS: Routine administration of AT3 in neonates receiving ECMO therapy was associated with tighter control of anticoagulation and a reduction in thrombotic events without increasing unwanted bleeding. However, circuit lifespan was unaffected. LEVEL OF EVIDENCE: Level III.

Management of Patients with Gastroschisis Requiring Extracorporeal Membrane Oxygenation for Concurrent Respiratory Failure.

Treatment of gastroschisis often requires multiple surgical procedures to re-establish abdominal domain, reduce abdominal contents, and eventually close the abdominal wall. In patients who have concomitant respiratory failure requiring extracorporeal membrane oxygenation (ECMO), this process becomes further complicated. This situation is rare and only five such cases have been reported in the ECMO registry database. Management of three of the five patients along with results and implications for future care of similar patients is discussed here. Two patients had respiratory failure due to meconium aspiration syndrome and one patient had persistent acidosis as well as worsening pulmonary hypertension leading to the decision of ECMO. The abdominal contents were placed in a spring-loaded silastic silo while on ECMO and primary closure was performed three to six days after the decannulation. All three patients survived and are developmentally appropriate. We recommend avoiding aggressively reducing the abdominal contents and using a silo to conservatively reducing the gastroschisis while the patient is on ECMO therapy. Keeping the intra-abdominal pressure below 20 mm Hg can possibly reduce ECMO days and ventilator time and has been shown to decrease morbidity and mortality. Patients with gastroschisis and respiratory failure requiring ECMO can have good outcomes despite the complexity of required care.

Venovenous Extracorporeal Membrane Oxygenation in Pediatric Respiratory Failure.

Conventional treatment of respiratory failure involves positive pressure ventilation that can worsen lung damage. Extracorporeal membrane oxygenation (ECMO) is typically used when conventional therapy fails. In this study, we evaluated the use of venovenous (VV)-ECMO for the treatment of severe pediatric respiratory failure at our institution. A retrospective analysis of pediatric patients (age 1-18) placed on ECMO in the last 15 years (1999-2014) by the pediatric surgery team for respiratory failure was performed. Five pediatric patients underwent ECMO (mean age 10 years; range, 2-16). All underwent VV-ECMO. Diagnoses were status asthmaticus (2), acute respiratory distress syndrome due to septic shock (1), aspergillus pneumonia (1), and respiratory failure due to parainfluenza (1). Two patients had severe barotrauma prior to ECMO initiation. Average oxygenation index (OI) prior to cannulation was 74 (range 23-122). No patients required conversion to VA-ECMO. The average ECMO run time was 4.4 days (range 2-6). The average number of days on the ventilator was 15 (range 4-27). There were no major complications due to the procedure. Survival to discharge was 100%. Average follow up is 4.4 years (range 1-15). A short run of VV-ECMO can be lifesaving for pediatric patients in respiratory failure. Survival is excellent despite severely elevated oxygen indices. VV-ECMO may be well tolerated and can be considered for severe pediatric respiratory failure.

Clinical outcome of maraviroc-containing therapy in heavily pre-treated HIV-1-infected patients.

Available data on the use of maraviroc (MVC) in clinical settings are limited. In this cohort study, the clinical outcomes of HIV-1-infected patients treated with MVC were analysed and the predictive values of different tropism assays were compared. Baseline viral tropism was assessed and compared by phenotypic (Trofile and MT-2) and genotypic assays. Virological and immunological responses were evaluated. In total, 62 predominantly extensively pre-treated patients started MVC [median GSS 2.0 (IQR 2.0-2.5)]. Tropism assays were performed on baseline samples of 58 patients (93.5%). Thirty-two samples (80.0%) were classified as R5 by Trofile, 41 (80.4%) by genotypic tropism test (GTT) and 17 (81.0%) by MT-2. At least two types of tropism assay were performed on samples from 39 patients, whereas in 15 patients all three assays were performed (concordance 84.8-94.1%). Plasma HIV-RNA was <50 copies/mL in 82.1%, 85.0% and 68.8% of patients after 12, 24 and 36 months, respectively; median CD4 cell increase was 199 (IQR 108-283), 291 (IQR 187-413) and 234 (IQR 106-444)cells/µL. The predictive values of different tropism assays were comparably high: at Month 24, 92.9% (Trofile and GTT) and 100.0% (MT-2) of patients had plasma HIV-RNA <50 copies/mL. Three patients stopped MVC treatment because of suspected side effects. Five patients died during follow-up. In this heavily pre-treated cohort, treatment with MVC was well tolerated and resulted in good immunological and virological responses. Results generated by the different tropism assays correlated well with each other and had a high predictive value.

Tracking of migrating cells under phase-contrast video microscopy with combined mean-shift processes.

In this paper, we propose a combination of mean-shift-based tracking processes to establish migrating cell trajectories through in vitro phase-contrast video microscopy. After a recapitulation on how the mean-shift algorithm permits efficient object tracking we describe the proposed extension and apply it to the in vitro cell tracking problem. In this application, the cells are unmarked (i.e., no fluorescent probe is used) and are observed under classical phase-contrast microscopy. By introducing an adaptive combination of several kernels, we address several problems such as variations in size and shape of the tracked objects (e.g., those occurring in the case of cell membrane extensions), the presence of incomplete (or noncontrasted) object boundaries, partially overlapping objects and object splitting (in the case of cell divisions or mitoses). Comparing the tracking results automatically obtained to those generated manually by a human expert, we tested the stability of the different algorithm parameters and their effects on the tracking results. We also show how the method is resistant to a decrease in image resolution and accidental defocusing (which may occur during long experiments, e.g., dozens of hours). Finally, we applied our methodology on cancer cell tracking and showed that cytochalasin-D significantly inhibits cell motility.

Evaluation of the VIDAS Listeria (LIS) immunoassay for the detection of Listeria in foods using demi-Fraser and Fraser enrichment broths, as modification of AOAC Official Method 999.06 (AOAC Official Method 2004.06).

A multilaboratory study was conducted to compare the VIDAS LIS immunoassay with the standard cultural methods for the detection of Listeria in foods using an enrichment modification of AOAC Official Method 999.06. The modified enrichment protocol was implemented to harmonize the VIDAS LIS assay with the VIDAS LMO2 assay. Five food types--brie cheese, vanilla ice cream, frozen green beans, frozen raw tilapia fish, and cooked roast beef--at 3 inoculation levels, were analyzed by each method. A total of 15 laboratories representing government and industry participated. In this study, 1206 test portions were tested, of which 1170 were used in the statistical analysis. There were 433 positive by the VIDAS LIS assay and 396 positive by the standard culture methods. A Chi-square analysis of each of the 5 food types, at the 3 inoculation levels tested, was performed. The resulting average Chi square analysis, 0.42, indicated that, overall, there are no statistical differences between the VIDAS LIS assay and the standard methods at the 5% level of significance.

Comparison of digital PCR platforms and semi-nested qPCR as a tool to determine the size of the HIV reservoir.

HIV persists in latently infected cells of patients on antiretroviral therapy (ART). This persistent proviral DNA reservoir is an important predictor of viral rebound upon therapy failure or interruption and forms a major obstacle towards cure. Accurate quantification of the low levels of persisting HIV DNA may aid patient monitoring and cure research. Digital PCR is a promising tool that enables direct absolute quantification with high sensitivity. With recent technological advances, several platforms are available to implement digital PCR in a clinical setting. Here, we compared two digital PCR platforms, the Quantstudio 3D (Life Technologies) and the QX100 (Bio-Rad) with a semi-nested qPCR on serial HIV DNA dilutions and DNA isolated from PBMCs of ART-suppressed patients. All three methods were able to detect target to the lowest levels of 2.5 HIV DNA copies. The QX100 excelled in having the least bias and highest precision, efficiency and quantitative linearity. Patient sample quantifications by the QX100 and semi-nested qPCR were highly agreeable by Bland-Altman analysis (0.01±0.32 log10). Due to the observation of false-positive signals with current digital PCR platforms however, semi-nested qPCR may still be preferred in a setup of low quantity detection to discriminate between presence or absence of HIV DNA.

Endothelial nitric oxide synthase deficient mice are protected from lipopolysaccharide induced acute lung injury.

Lipopolysaccharide (LPS) derived from the outer membrane of gram-negative bacteria induces acute lung injury (ALI) in mice. This injury is associated with lung edema, inflammation, diffuse alveolar damage, and severe respiratory insufficiency. We have previously reported that LPS-mediated nitric oxide synthase (NOS) uncoupling, through increases in asymmetric dimethylarginine (ADMA), plays an important role in the development of ALI through the generation of reactive oxygen and nitrogen species. Therefore, the focus of this study was to determine whether mice deficient in endothelial NOS (eNOS-/-) are protected against ALI. In both wild-type and eNOS-/- mice, ALI was induced by the intratracheal instillation of LPS (2 mg/kg). After 24 hours, we found that eNOS-/-mice were protected against the LPS mediated increase in inflammatory cell infiltration, inflammatory cytokine production, and lung injury. In addition, LPS exposed eNOS-/- mice had increased oxygen saturation and improved lung mechanics. The protection in eNOS-/- mice was associated with an attenuated production of NO, NOS derived superoxide, and peroxynitrite. Furthermore, we found that eNOS-/- mice had less RhoA activation that correlated with a reduction in RhoA nitration at Tyr34. Finally, we found that the reduction in NOS uncoupling in eNOS-/- mice was due to a preservation of dimethylarginine dimethylaminohydrolase (DDAH) activity that prevented the LPS-mediated increase in ADMA. Together our data suggest that eNOS derived reactive species play an important role in the development of LPS-mediated lung injury.

Identification of high versus lower risk clinical subgroups in a group of adult patients with supratentorial anaplastic astrocytomas.

The present work investigates whether computer-assisted techniques can contribute any significant information to the characterization of astrocytic tumor aggressiveness. Two complementary computer-assisted methods were used. The first method made use of the digital image analysis of Feulgen-stained nuclei, making it possible to compute 15 morphonuclear and 8 nuclear DNA content-related (ploidy level) parameters. The second method enabled the most discriminatory parameters to be determined. This second method is the Decision Tree technique, which forms part of the Supervised Learning Algorithms. These two techniques were applied to a series of 250 supratentorial astrocytic tumors of the adult. This series included 39 low-grade (astrocytomas, AST) and 211 high-grade (47 anaplastic astrocytomas, ANA, and 164 glioblastomas, GBM) astrocytic tumors. The results show that some AST, ANA and GBM did not fit within simple logical rules. These "complex" cases were labeled NC-AST, NC-ANA and NC-GBM because they were "non-classical" (NC) with respect to their cytological features. An analysis of survival data revealed that the patients with NC-GBM had the same survival period as patients with GBM. In sharp contrast, patients with ANA survived significantly longer than patients with NC-ANA. In fact, the patients with ANA had the same survival period as patients who died from AST, while the patients with NC-ANA had a survival period similar to those with GBM. All these data show that the computer-assisted techniques used in this study can actually provide the pathologist with significant information on the characterization of astrocytic tumor aggressiveness.