Societal importance of Antarctic negative feedbacks on climate change: blue carbon gains from sea ice, ice shelf and glacier losses.

Diminishing prospects for environmental preservation under climate change are intensifying efforts to boost capture, storage and sequestration (long-term burial) of carbon. However, as Earth's biological carbon sinks also shrink, remediation has become a key part of the narrative for terrestrial ecosystems. In contrast, blue carbon on polar continental shelves have stronger pathways to sequestration and have increased with climate-forced marine ice losses-becoming the largest known natural negative feedback on climate change. Here we explore the size and complex dynamics of blue carbon gains with spatiotemporal changes in sea ice (60-100 MtCyear-1), ice shelves (4-40 MtCyear-1 = giant iceberg generation) and glacier retreat (< 1 MtCyear-1). Estimates suggest that, amongst these, reduced duration of seasonal sea ice is most important. Decreasing sea ice extent drives longer (not necessarily larger biomass) smaller cell-sized phytoplankton blooms, increasing growth of many primary consumers and benthic carbon storage-where sequestration chances are maximal. However, sea ice losses also create positive feedbacks in shallow waters through increased iceberg movement and scouring of benthos. Unlike loss of sea ice, which enhances existing sinks, ice shelf losses generate brand new carbon sinks both where giant icebergs were, and in their wake. These also generate small positive feedbacks from scouring, minimised by repeat scouring at biodiversity hotspots. Blue carbon change from glacier retreat has been least well quantified, and although emerging fjords are small areas, they have high storage-sequestration conversion efficiencies, whilst blue carbon in polar waters faces many diverse and complex stressors. The identity of these are known (e.g. fishing, warming, ocean acidification, non-indigenous species and plastic pollution) but not their magnitude of impact. In order to mediate multiple stressors, research should focus on wider verification of blue carbon gains, projecting future change, and the broader environmental and economic benefits to safeguard blue carbon ecosystems through law.

Supramolecular surface functionalization via catechols for the improvement of cell-material interactions.

Optimization of cell-material interactions is crucial for the success of synthetic biomaterials in guiding tissue regeneration. To do so, catechol chemistry is often used to introduce adhesiveness into biomaterials. Here, a supramolecular approach based on ureido-pyrimidinone (UPy) modified polymers is combined with catechol chemistry in order to achieve improved cellular adhesion onto supramolecular biomaterials. UPy-modified hydrophobic polymers with non-cell adhesive properties are developed that can be bioactivated via a modular approach using UPy-modified catechols. It is shown that successful formulation of the UPy-catechol additive with the UPy-polymer results in surfaces that induce cardiomyocyte progenitor cell adhesion, cell spreading, and preservation of cardiac specific extracellular matrix production. Hence, by functionalizing supramolecular surfaces with catechol functionalities, an adhesive supramolecular biomaterial is developed that allows for the possibility to contribute to biomaterial-based regeneration.

Prevalence of phylogroups and O25/ST131 in susceptible and extended-spectrum ß-lactamase-producing Escherichia coli isolates, the Netherlands.

To assess the distribution of phylogroups and O25/ST131 in the Netherlands, we performed a real-time polymerase chain reaction (PCR) on a collection of 108 wild-type Escherichia coli (WT-EC) and 134 extended-spectrum ß-lactamase-producing E. coli (ESBL-EC). Phylogroup B2 was predominant, but ESBL-EC were less likely to belong to this phylogroup (48.5%) than were WT-EC (66.7%; p = 0.005). In WT-EC, phylogroups B2 and D seem to be more virulent, having a higher prevalence among midstream urine isolates and blood culture isolates, than in catheter-related urine isolates (83.3% and 87.9% vs. 61.9%; p 0.048). O25/ST131 is associated with ESBL production, being almost absent among phylogroup B2 WT-EC (61.5% vs. 5.6%; p < 0.001).

Designing environmental research for impact.

Transdisciplinary research, involving close collaboration between researchers and the users of research, has been a feature of environmental problem solving for several decades, often spurred by the need to find negotiated outcomes to intractable problems. In 2005, the Australian government allocated funding to its environment portfolio for public good research, which resulted in consecutive four-year programmes (Commonwealth Environmental Research Facilities, National Environmental Research Program). In April 2014, representatives of the funders, researchers and research users associated with these programmes met to reflect on eight years of experience with these collaborative research models. This structured reflection concluded that successful multi-institutional transdisciplinary research is necessarily a joint enterprise between funding agencies, researchers and the end users of research. The design and governance of research programmes need to explicitly recognise shared accountabilities among the participants, while respecting the different perspectives of each group. Experience shows that traditional incentive systems for academic researchers, current trends in public sector management, and loose organisation of many end users, work against sustained transdisciplinary research on intractable problems, which require continuity and adaptive learning by all three parties. The likelihood of research influencing and improving environmental policy and management is maximised when researchers, funders and research users have shared goals; there is sufficient continuity of personnel to build trust and sustain dialogue throughout the research process from issue scoping to application of findings; and there is sufficient flexibility in the funding, structure and operation of transdisciplinary research initiatives to enable the enterprise to assimilate and respond to new knowledge and situations.

The influence of matrix (an)isotropy on cardiomyocyte contraction in engineered cardiac microtissues.

In the cardiac microenvironment, cardiomyocytes (CMs) are embedded in an aligned and structured extracellular matrix (ECM) to maintain the coordinated contractile function of the heart. The cardiac fibroblast (cFB) is the main cell type responsible for producing and remodeling this matrix. In cardiac diseases, however, adverse remodeling and CM death may lead to deterioration of the aligned myocardial structure. Here, we present an in vitro cardiac model system with uniaxial and biaxial constraints to induce (an)isotropy in 3D microtissues, thereby mimicking 'healthy' aligned and 'diseased' disorganized cardiac matrices. A mixture of neonatal mouse CMs and cFBs was resuspended in a collagen-matrigel hydrogel and seeded to form microtissues to recapitulate the in vivo cellular composition. Matrix disarray led to a stellate cell shape and a disorganized sarcomere organization, while CMs in aligned matrices were more elongated and had aligned sarcomeres. Although matrix disarray has no detrimental effect on the force generated by the CMs, it did have a negative effect on the homogeneity of contraction force distribution. Furthermore, proliferation of the cFBs affected microtissue contraction as indicated by the negative correlation between the percentage of cFBs in the microtissues and their beating frequency. These results suggest that in regeneration of the diseased heart, reorganization of the disorganized matrix will contribute to recover the coordinated contraction but restoring the ratio in cellular composition (CMs and cFBs) is also a prerequisite to completely regain tissue function.

Guidelines for the management of gastroenteropancreatic neuroendocrine (including carcinoid) tumours (NETs).

These guidelines update previous guidance published in 2005. They have been revised by a group who are members of the UK and Ireland Neuroendocrine Tumour Society with endorsement from the clinical committees of the British Society of Gastroenterology, the Society for Endocrinology, the Association of Surgeons of Great Britain and Ireland (and its Surgical Specialty Associations), the British Society of Gastrointestinal and Abdominal Radiology and others. The authorship represents leaders of the various groups in the UK and Ireland Neuroendocrine Tumour Society, but a large amount of work has been carried out by other specialists, many of whom attended a guidelines conference in May 2009. We have attempted to represent this work in the acknowledgements section. Over the past few years, there have been advances in the management of neuroendocrine tumours, which have included clearer characterisation, more specific and therapeutically relevant diagnosis, and improved treatments. However, there remain few randomised trials in the field and the disease is uncommon, hence all evidence must be considered weak in comparison with other more common cancers.

Does minimal access major surgery in the newborn hurt less? An evaluation of cumulative opioid doses.

BACKGROUND: Minimal access surgery (MAS) in adults is associated with less postoperative pain in comparison to conventional 'open' surgery. It is not known whether this holds true for neonates as well. Less pain would imply that opioid consumption can be reduced, which has a beneficial effect on morbidity. AIM: To evaluate potential differences in' opioid consumption between neonates undergoing thoracoscopic minimal access surgery or conventional surgery of esophageal atresia (EA) and congenital diaphragmatic hernia (CDH). METHODS: In this retrospective cohort study we included two controls for each MAS patient, matched on diagnosis, sex and age at surgery. Opioid dose titration was based on validated pain scores (VAS and COMFORT behaviour), applied by protocol. Cumulative opioid doses at 12, 24, 48 h and 7 days postoperatively were compared between groups with the Mann-Whitney test. RESULTS: The study group consisted of 24 MAS patients (14 EA; 10 CDH). These were matched to 48 control patients (28 EA; 20 CDH). At none of the time points cumulative opioid (median in mg/kg (IQR)) doses significantly differed between MAS patients and controls, both with CDH and EA. For example at 24 h postoperative for CDH patients cumulative opioid doses were [0.84(0.61-1.83) MAS vs. 1.06(0.60-1.36) p=1.0] controls, For EA patients at 24 h the cumulative opioid doses were [0.48(0.30-0.75) MAS vs. 0.49(0.35-0.79) p=0.83] controls. This held true for the postoperative pain scores as well. CONCLUSIONS: Minimal access surgery for the repair of esophageal atresia or congenital diaphragmatic hernia is not associated with less cumulative opioid doses.

Pre- and postnatal diagnosis and outcome of fetuses and neonates with esophageal atresia and tracheoesophageal fistula.

OBJECTIVES: Clinical symptoms and ultrasound signs during pregnancy could suggest the presence of esophageal atresia (EA). However, most often EA is diagnosed postnatally. The aim of our study is to evaluate the course and outcome for prenatally and postnatally diagnosed EA. In addition, we studied the outcome of isolated versus nonisolated EA. METHODS: In a retrospective data analysis, ultrasound characteristics, maternal and neonatal variables as well as clinical outcome were compared for fetuses/neonates with prenatal (n = 30) or postnatal (n = 49) diagnosis of EA. Clinical outcome in terms of morbidity and mortality of isolated EA was compared with that of EA complicated by chromosomal or structural anomalies. RESULTS: Prenatally diagnosed children were born 2 weeks earlier than postnatally diagnosed children (36.4 weeks vs 38.2 weeks; P = 0.02). The former had higher mortality rates (30 vs 12%; P = 0.05) and more associated anomalies (80 vs 59%; P = 0.04). In both subsets, there was a high morbidity rate in the survivors (not significant). Nonisolated EA was associated with greater occurrence of polyhydramnios (53 vs 27%; P = 0.04) and higher mortality rate (28 vs 0%; P = 0.002). CONCLUSIONS: Mortality was significantly higher in prenatally diagnosed infants and in infants with additional congenital anomalies. Isolated EA is associated with good outcome.

Minimally invasive pediatric surgery: Increasing implementation in daily practice and resident's training.

BACKGROUND: In 1998, the one-year experience in minimally invasive abdominal surgery in children at a pediatric training center was assessed. Seven years later, we determined the current status of pediatric minimally invasive surgery in daily practice and surgical training. METHODS: A retrospective review was undertaken of all children with intra-abdominal operations performed between 1 January 2005 and 31 December 2005. RESULTS: The type of operations performed ranged from common interventions to demanding laparoscopic procedures. 81% of all abdominal procedures were performed laparoscopically, with a complication rate stable at 6.9%, and conversion rate decreasing from 10% to 7.4%, compared to 1998. There were six new advanced laparoscopic procedures performed in 2005 as compared to 1998. The children in the open operated group were significantly smaller and younger than in the laparoscopic group (p < 0.001 and p = 0.001, respectively). The majority (64.2%) of the laparoscopic procedures were performed by a trainee. There was no difference in the operating times of open versus laparoscopic surgery, or of procedures performed by trainees versus staff surgeons. Laparoscopy by trainees did not have a negative impact on complication or conversion rates. CONCLUSIONS: Laparoscopy is an established approach in abdominal procedures in children, and does not hamper surgical training.

Duhamel procedure: a comparative retrospective study between an open and a laparoscopic technique.

BACKGROUND: Few studies are available comparing open with laparoscopic treatment of Hirschsprung's disease. This study compares a laparoscopic series of 30 patients with a historical open series of 25 patients. METHODS: The charts of all patients having had a Duhamel procedure in the period from June 1987 through July 2003 were retrospectively reviewed. Open procedures were performed until March 1994. Patients with extended aganglionosis, pre-Duhamel ostomy, or syndrome were excluded from the study. End points were intraoperative complications, postoperative complications, time to first feeding, hospital stay, and outcome at follow-up such as stenosis, enterocolitis, constipation, fecal incontinence, and enuresis. RESULTS: Twenty-five patients had an open Duhamel (OD) and 30 had a laparoscopic one (LD). There were no differences in patient characteristics and there were no intraoperative complications in either group. Time to first oral feeds was significantly longer in the OD group as was the duration of hospital stay. No significant differences at follow-up were observed but there was a tendency for a higher enterocolitis rate in the LD group. In contrast, the adhesive obstruction and enuresis rates were higher in the OD group. Cosmetic results were superior in the LD group. CONCLUSIONS: Except for a significantly shorter hospital stay and shorter time to first oral feeds in favor of LD, no significant differences could be observed. The cosmetic result was not an end point but there was no doubt that it was better in the LD group. Although not statistically significant different, there were no adhesive bowel obstructions in the LD group compared with 3 of 25 in the OD group. Fecal incontinence was not encountered in either group.

Thoracoscopic tracheoaortopexia for the treatment of life-threatening events in tracheomalacia.

BACKGROUND: Life-threatening events resulting from tracheomalacia are a well-known complication of infants with esophageal atresia. Aortopexy is accepted as the most effective method for managing severe life-threatening and localized tracheomalacia with a success rate of 85% to 90%. Since the advent of minimally invasive surgery (MIS), the procedure also can be performed using thoracoscopic MIS. METHODS: Between January 2002 and November 2005, six children with esophageal atresia were treated using MIS for life-threatening events attributable to tracheomalacia. RESULTS: The patients tolerated the thoracoscopic procedure well, and all tracheoaortopexies could be performed thoracoscopically. There were two recurrences, which could be treated using thoracoscopy. After a follow-up period of 27 months (range, 10-45 months), all the patients are doing well and have had no more life-threatening events. CONCLUSIONS: Although this is the largest thoracoscopic series to date, the series is too small for any conclusions yet to be drawn. Thoracoscopic tracheoaortopexia is feasible and offers the advantages of MIS.

Jejunal pedicle grafts for reconstruction of the esophagus in children.

OBJECTIVE: Reconstruction of the esophagus in children remains a challenge. Although jejunal grafts retain peristaltic activity, large series with long-term follow up are rare. We like to present our experience in a series of 24 children. METHODS: In the period 1988 through 2005, 24 children received an orthotopic jejunal pedicle graft reconstruction of the esophagus. Nineteen had esophageal atresia (18 had no distal fistula; all but 1 had a jejunal graft as a primary procedure), 3 had an extensive caustic stricture, and 2 had a peptic stricture. All strictures had been dilated many times, and peptic strictures had been treated with antireflux surgery as well. Median age at reconstruction was 76 days in the esophageal atresia group. The technique involves a right-sided thoracotomy with preparation of the esophageal ends or resection of the diseased esophagus. At laparotomy, a small pediculated jejunal graft is prepared and placed transhiatally in an orthotopic position in the right chest. RESULTS: All patients survived, and none of the grafts were lost. There were 5 intrathoracic leaks, 4 in the esophageal atresia group and 1 in peptic stricture group, requiring reoperation in 1. In the esophageal atresia group, there was 1 early distal stenosis requiring reoperation. In patients in which the distal esophagus was preserved (esophageal atresia and caustic stricture group), there were always signs of distal functional subobstruction, responding to dilatation in all but 1 patient. Gastroesophageal reflux was not a problem except for 1 patient with esophageal atresia, in whom the distal esophagus was resected because of ongoing distal obstruction with dilatation of the graft. Most patients eat and grow well, and respiratory problems were rare. CONCLUSION: Orthotopic jejunal pedicle graft reconstruction of the esophagus in children is a demanding operation with considerably morbidity but good long-term results.

Factors associated with recurrence and metastasis in sacrococcygeal teratoma.

BACKGROUND: Sacrococcygeal teratoma (SCT) is a relatively uncommon tumour, with a high risk of recurrence and metastasis. The factors associated with recurrence and metastatic disease were studied. METHODS: A retrospective review was conducted of 173 children with SCT treated between January 1970 and February 2003 at the paediatric surgical centres in the Netherlands. Risk factors were identified by univariate and multivariate analysis. RESULTS: Eight children died shortly after birth or around the time of operation. Nine children, all over 18 months old, had metastases at presentation. Four teratomas with metastasis showed mature histology of the primary tumour. Nineteen children had recurrence of SCT a median interval of 10 months (range 32 days to 35 months) after primary surgery. Risk factors for recurrence were pathologically confirmed incomplete resection (odds ratio (OR) 6.54 (95 per cent confidence interval (c.i.) 2.11 to 20.31)), immature histology (OR 5.74 (95 per cent c.i. 1.49 to 22.05)) and malignant histology (OR 12.83 (95 per cent c.i. 3.27 to 50.43)). Size, Altman classification, age and decade of diagnosis were not risk factors for recurrence. One-third of the recurrences showed a shift towards histological immaturity or malignancy, compared with the primary tumour. Seven patients died after recurrence, five with malignant disease. CONCLUSION: This national study showed that SCT recurred in 11 per cent of the children within 3 years of operation. Risk factors were immature and malignant histology, or incomplete resection. Mature teratoma has the biological capability to become malignant.

Laparoscopically assisted liver biopsy with a hemostatic plug.

BACKGROUND: Percutaneous and open liver biopsies are routine procedures for diagnosing liver pathology. However, the procedure can carry significant morbidity and even mortality, especially in the event of an uncorrectable coagulopathy or a highly vascular tumor. METHODS: A technique described for use in such circumstances involves laparoscopy for identification of the lesion to be biopsied, enables placement of a gelatin hemostatic plug in the core biopsy tract, and confirms hemostasis after percutaneous plugging of the biopsy site. RESULTS: The technique was successfully used for seven patients: six patients with hepatic coagulopathy and one with a highly vascular liver tumor. There were no complications during either the intra- or postoperative period. The patients experienced minimal postoperative discomfort and returned to baseline activity on the first postoperative day. CONCLUSION: The authors believe that the described technique of biopsy site plugging offers a safe alternative for liver biopsy among patients with an uncorrectable coagulopathy and those requiring a biopsy before correction of the bleeding disorder.

Long-term outcome of laparoscopic Nissen, Toupet, and Thal antireflux procedures for neurologically normal children with gastroesophageal reflux disease.

BACKGROUND: Nissen fundoplication is the most popular laparoscopic operation for the management of gastroesophageal reflux disease (GERD). Partial fundoplications seem to be associated with a lower incidence of postoperative dysphagia, and thus a better quality of life for patients. The aim of this study was to compare the long-term outcome in neurologically normal children who underwent laparoscopic Nissen, Toupet, or Thal procedures in three European centers with a large experience in laparoscopic antireflux procedures. METHODS: This study retrospectively analyzed the data of 300 consecutive patients with GERD who underwent laparoscopic surgery. The first 100 cases were recorded for each team, with the first team using the Toupet, the second team using the Thal, and the third team using the Nissen procedure. The only exclusion criteria for this study was neurologic impairment. For this reason, 66 neurologically impaired children (52 Thal, 10 Nissen, 4 Toupet) were excluded from the study. This evaluation focuses on the data for the remaining 238 neurologically normal children. The patients varied in age from 5 months to 16 years (median, 58 months). The median weight was 20 kg. All the children underwent a complete preoperative workup, and all had well-documented GERD. The position of the trocars and the dissection phase were similar in all the procedures, as was the posterior approximation of the crura. The short gastric vessels were divided in only six patients (2.5%). The only difference in the surgical procedures was the type of antireflux valve created. RESULTS: The median duration of surgery was 70 min. There was no mortality and no conversion in this series. A total of 12 (5%) intraoperative complications (5 Nissen, 5 Toupet, 2 Thal) and 13 (5.4%) postoperative complications (3 Toupet, 4 Nissen, 6 Thal) were recorded. Only six (2.5%) redo procedures (2 Thal, 2 Toupet, 2 Nissen) were performed. After a minimum follow-up period of 5 years, all the children were free of symptoms except nine (3.7%), who sometimes still require medication. The incidence of complications and redo surgery for the three procedures analyzed with the Mann-Whitney U test are not statistically significant. CONCLUSIONS: For pediatric patients with GERD, laparoscopic Nissen, Toupet, and Thal antireflux procedures yielded satisfactory results, and none of the approaches led to increased dysphagia. The 5% rate for intraoperative complications seems linked to the learning curve period. The authors consider the three procedures as extremely effective for the treatment of children with GERD, and they believe that the choice of one procedure over the other depends only on the surgeon's experience. Parental satisfaction with laparoscopic treatment was very high in all the three series.

The clinical impact of a combined gamma camera/CT imaging system on somatostatin receptor imaging of neuroendocrine tumours.

AIM: With a combined gamma camera/CT imaging system, CT images are obtained which are inherently registered to the emission images and can be used for the attenuation correction of SPECT and for mapping the functional information from these nuclear medicine tomograms onto anatomy. The aim of this study was to evaluate the clinical impact of SPECT/CT using such a system for somatostatin receptor imaging (SRI) of neuroendocrine tumours. MATERIALS AND METHODS: SPECT/CT imaging with (111)In-Pentetreotide was performed on 29 consecutive patients, the majority of whom had carcinoid disease. All SPECT images were first reported in isolation and then re-reported with the addition of the CT images for functional anatomical mapping (FAM). RESULTS: Fifteen of the 29 SPECT images were reported as abnormal, and in 11 of these abnormal images (73%) FAM was found to either establish a previously unknown location (7/11) or change the location (4/11) of at least one lesion. The revised location could be independently confirmed in 64% of these cases. Confirmation of location was not possible in the other patients due to either a lack of other relevant investigations, or the fact that lesions seen in the SPECT images were not apparent in the other investigations. FAM affected patient management in 64% of the cases where the additional anatomical information caused a change in the reported location of lesions. CONCLUSION: These results imply that FAM can improve the reporting accuracy for SPECT SRI with significant impact on patient management.

Carbon dioxide differentially affects the cytokine release of macrophage subpopulations exclusively via alteration of extracellular pH.

BACKGROUND: The improved outcome after endoscopic surgery has been attributed to less surgical trauma. However, the underlying mechanisms are not fully understood, and direct effects of CO2 used for pneumoperitoneum, cellular acidification, and/or the lack of air contamination have been postulated to additionally modulate immune functions during endoscopic surgery. We investigated the effects of CO2 incubation, extracellular acidification, and air contamination on the inflammatory response of two distinct macrophage populations. METHODS: R2 and NR 8383 rat macrophage cell lines were used. Interleukin-6 (IL-6) and nitric oxide after lipopolysaccharide (LPS) stimulation were determined in these sets of experiments: incubation in 100% CO2, 5% CO2, and room air for 2h; incubation at pH 7.4, 6.5, and 5.5 for 2 h in 5% CO2; and incubation in 100% CO2, 5% CO2 and room air in fixed pH 6.3. The extracellular pH was monitored during incubation. We determined the alteration of intracellular pH in cells subjected to extracellular acidification by fluorescence microscopy. RESULTS: Extracellular pH decreased to 6.3 during 100% CO2 incubation. IL-6 release was reduced after CO2 incubation in NR 8383 cells and increased in R2 cells (p < 0.05). It was not altered by air incubation. Decreasing the extracellular pH to 6.5 mimicked the effects of CO2 and a decrease to 5.5 suppressed IL-6 release in both cell lines. In fixed pH at 6.3, CO2 and air incubation had no effect. CO2 and pH had no impact on nitric oxide release and vitality. Intracellular pH decreased with extracellular acidification without significant difference between the two cell lines. CONCLUSIONS: A decrease in extracellular pH during incubation in CO2 differentially affects IL-6 release in macrophage subpopulations. This may explain contradictory results in the literature. Moreover, we demonstrated that air contamination does not affect macrophage cytokine release. The decrease in extracellular pH is the primary underlying mechanism of the alteration of macrophage cytokine release after CO2 incubation, and it appears that the ability to maintain intracellular pH is not determined by the effects of CO2 or extracellular acidification.