Warming and redistribution of nitrogen inputs drive an increase in terrestrial nitrous oxide emission factor

Anthropogenic nitrogen inputs cause major negative environmental impacts, including emissions of the important greenhouse gas N2O. Despite their importance, shifts in terrestrial N loss pathways driven by global change are highly uncertain. Here we present a coupled soil-atmosphere isotope model (IsoTONE) to quantify terrestrial N losses and N2O emission factors from 1850-2020. We find that N inputs from atmospheric deposition caused 51% of anthropogenic N2O emissions from soils in 2020. The mean effective global emission factor for N2O was 4.3 ± 0.3% in 2020 (weighted by N inputs), much higher than the surface area-weighted mean (1.1 ± 0.1%). Climate change and spatial redistribution of fertilisation N inputs have driven an increase in global emission factor over the past century, which accounts for 18% of the anthropogenic soil flux in 2020. Predicted increases in fertilisation in emerging economies will accelerate N2O-driven climate warming in coming decades, unless targeted mitigation measures are introduced.

[CHAOS in neonatal emergency care? : Tracheal agenesis in the obstetric theatre]

Tracheal agenesis (TA) is a very rare congenital malformation of unknown aetiology. It is often associated with polymalformative syndromes; the neonates commonly present a critical condition during post-natal treatment. Pathology revolves around the triad of aphonia, respiratory distress syndrome and impossibility of endotracheal intubation. In contrast to the most important differential diagnosis, i. e., congenital high airway obstruction syndrome (CHAOS), surgical airway management is also impossible due to the absence of tracheal structures. In most cases, prognosis is very poor. The case report at hand portrays the treatment of a neonate suffering from tracheal agenesis.

Outcomes from television sets toppling onto toddlers

OBJECTIVE

To assess outcomes of trauma caused by television sets falling onto children.

METHODS

Retrospective review of medical charts of 183 children aged 7 years and younger hospitalized for injuries caused by falling television sets. Descriptive statistics were applied.

DATA SOURCES

Phase 2 (1988-1995) and phase 3 (1995-1999) of the National Pediatric Trauma Registry.

OUTCOME MEASURES

Demographics, injured body region, injury severity measured by the Injury Severity Score, length of hospital stay, admission to the intensive care unit, surgical intervention, in-hospital death rate, disability resulting from the injury, and disposition at discharge from the hospital.

RESULTS

The sample population represented 0.5% of all National Pediatric Trauma Registry admissions in this age group. More than half (57.4%) of the children were boys, and more than three quarters (76.0%) were 1 to 4 years of age. In most cases (95.1%), the injury occurred at home. Most children (68.3%) sustained head injury, and 43.7% sustained injuries to multiple body regions. More than a quarter (28.4%) of the children had injuries of moderate to critical severity (Injury Severity Score, 10-75), about a third (31.1%) required admission to the intensive care unit, and 20.2% needed 1 or more surgical interventions. The average length of hospitalization was 3.3 days. Five children (2.7%) died, and 48 (26.2%) developed functional limitations, which required discharge to a rehabilitation facility in 5 cases. Most (94.0%) of the children returned to their home. The proportion of television set-related injuries increased more than 100% during the study period.

CONCLUSIONS

The injuries reported are not trivial. Not only did they require hospitalization, but they also resulted in an in-hospital death rate comparable to the 2.5% rate observed in children of the same age group injured by unintentional blunt trauma, inclusive of motor vehicle traffic-related injuries. Since virtually all American children are at risk for such injury, we suggest that television set designs be modified to reduce the incidence and severity of the problem.

Ultrasound in the diagnosis of fractures in children

We compared the results of primary ultrasonographic examination of 163 children with 224 suspected fractures with the subsequent radiological findings. The aim was to assess the value of ultrasound in the diagnosis of fractures in children. We found a good correlation for fractures of the long bones of the upper and lower limbs. Ultrasound was most reliable for the detection of simple femoral and humeral diaphyseal fractures and fractures of the forearm. It was less dependable for compound injuries and fractures adjacent to joints, lesions of the small bones of the hand and foot, non-displaced epiphyseal fractures (Salter-Harris type 1) or those with a fracture line of less than 1mm.

We were able to distinguish several types of fracture in which the use of ultrasound alone gave reliable information and further radiography was unnecessary. We discuss the advantages and disadvantages of skeletal ultrasonographic studies in children.

Ultrasound in the diagnosis of fractures in children

We compared the results of primary ultrasonographic examination of 163 children with 224 suspected fractures with the subsequent radiological findings. The aim was to assess the value of ultrasound in the diagnosis of fractures in children. We found a good correlation for fractures of the long bones of the upper and lower limbs. Ultrasound was most reliable for the detection of simple femoral and humeral diaphyseal fractures and fractures of the forearm. It was less dependable for compound injuries and fractures adjacent to joints, lesions of the small bones of the hand and foot, non-displaced epiphyseal fractures (Salter-Harris type 1) or those with a fracture line of less than 1mm. We were able to distinguish several types of fracture in which the use of ultrasound alone gave reliable information and further radiography was unnecessary. We discuss the advantages and disadvantages of skeletal ultrasonographic studies in children.

Injuries to children with attention deficit hyperactivity disorder

OBJECTIVES

To determine differences between hospital admitted injuries to children with preinjury attention deficit hyperactivity disorder (ADHD) and injuries to those with no preinjury conditions (NO).

DESIGN

Comparative analysis, excluding fatalities, of ADHD patients (n = 240) to NO patients (n = 21 902), 5 through 14 years of age.

OUTCOME MEASURES

Demographics, injury characteristics, length of stay, admission to the intensive care unit, surgical intervention, disability, and disposition at discharge.

DATA SOURCE

Retrospective review of charts submitted by more than 70 hospitals participating in the National Pediatric Trauma Registry between October 1988 and April 1996.

RESULTS

Compared with the NO children, the children with ADHD were more likely to be boys (87.9% vs 66.5%), to be injured as pedestrians (27.5% vs 18.3%) or bicyclists (17.1% vs 13.8%), and to inflict injury to themselves (1.3% vs 0.1%). They were more likely to sustain injuries to multiple body regions (57.1% vs 43%), to sustain head injuries (53% vs 41%), and to be severely injured as measured by the Injury Severity Score (12.5% vs 5.4%) and the Glasgow Coma Scale (7.5% vs 3.4%). The ADHD mean length of stay was 6.2 days versus 5.4 in the NO group. In both groups, 40% had surgery, but the ADHD children were admitted more frequently to the intensive care unit (37.1% vs 24.1%). The injury led to disability in 53% of the children with ADHD vs 48% of the NO children. Children with ADHD with any disability were twice as likely to be discharged to rehabilitation/extended care than were the NO children.

CONCLUSIONS

Injured children with ADHD are more likely to sustain severe injuries than are children without ADHD. More research is needed to identify prevention efforts specifically targeted at this population.

[Effect of endoscopic surgery techniques in children on ventilation]

The purpose of our study was to show the effects of laparoscopic procedures on the ventilation of children. We measured an increase of ventilation pressures (Pmax, Ppfat and Pmean) of 28, 35 and 48% respectively. petCO2 rose from 35 to 41 +/- 2 mmHg. There was no loss of body temperature in any child. Laparoscopic procedures as seen here for appendectomy or diagnostic exploration in children of 13.5 kg body weight or more caused no problems that were clinically evident. The increase of ventilation pressure could be attenuated by choosing the parameters of ventilation (e.g. flow, I:E ratio) in such a way that Pmax does not exceed 20 mbar. Alternatively, pressure-controlled ventilation may be used, adjusting petCO2 by ventilation frequency. In any case there must be a strict control of all possible side effects of laparoscopy, such as cutaneous emphysema or pneumothorax.

[Aggressive fibromatosis in childhood]

Despite its benign microscopic appearance and nonmetastatic behavior, aggressive fibromatosis infiltrates neighboring tissues and has a considerably high recurrence rate (30%-60%). It is a rare lesion (0.03%-0.1% of all tumors) with an incidence of between two and four cases per million residents and per year. There is no agreement regarding the etiology of fibromatosis. Hormonal, traumatic and genetic influences have been described. It is a common manifestation in Gardener syndrome. The treatment of choice is broad surgical resection. When resection is incomplete or impossible, radiotherapy, chemotherapy or chemotherapy in combination with hyperthermia is the second choice of treatment. On the basis of five children observed, we discuss the etiologic factors, classification, clinical aspects and results of surgical and medical therapy.

The role of pancreatic innervation and cholecystokinin in the intestinal phase of pancreatic polypeptide release in conscious dogs

Besides vagal cholinergic mechanisms, pancreatic polypeptide (PP) secretion is thought to be mediated by hormones. This study was performed to delineate the role of extrinsic pancreatic innervation and cholecystokinin (CCK) in amino acid- and fat-stimulated PP secretion. In ten mongrel dogs, pancreatic denervation was performed by the method of Debas et al. [3]. Total denervation of the pancreas did not alter PP response to intraduodenal application of amino acids (integrated output 24,434 +/- 3260 pmol/1 x 120 min before vs 22,797 +/- 2470 pmol/1 x 120 min after operation) and to intraduodenal fat solution (19,595 +/- 2121 pmol/1 x 120 min vs 19,983 +/- 2031 pmol/1 x 120 min). Also, no significant differences were measured in CCK release (491 +/- 71 pmol/1 x 120 min vs 430 +/- 57 pmol/1 x 120 min for amino acids, 571 = 63 pmol/1 x 120 min vs 563 +/- 89 pmol/1 x 120 min for fat solution). Plasma PP and CCK levels were compared by linear regression analysis. Correlations between PP and CCK were high in the intact pancreas (amino acids, r = 0.92; fat, r = 0.99) as well as in the denervated pancreas (r = 0.93 amino acids and r = 0.98 fat). These results show that extrinsic pancreatic innervation does not influence PP and CCK release after intraduodenal amino acids or fat solution and that PP secretion seems to be mediated to some extent through the release of CCK.

Hydroxyethyl starch does not improve pancreas preservation with HTK

The effect of hydroxyethyl starch on pancreas preservation with cardioplegic histidine-tryptophan-ketoglutarate solution (HTK) was investigated. The study was performed using an in vitro reperfusion system of the porcine pancreas. During organ preservation pancreatic weight, arterial pressure, volume flow, and washout of amylase and lactate were quantified. Addition of hydroxyethyl starch did not affect arteriovenous volume flow or washout of amylase and lactate during protective perfusion after pancreas preparation. However, hydroxyethyl starch in HTK prevented an increase in pancreatic weight at the end of the protective perfusion (102.2 +/- 4.55% vs 127.8 +/- 4.62% in controls; p < 0.005) and after 24 h cold ischemia (72.9 +/- 3.91% vs. 83.5 +/- 3.49% in controls; p < 0.05). Hydroxyethyl starch did not affect postischemic organ quality assessed during reperfusion in a perfusion chamber by pancreatic vascular resistance, amylase and lactate release, insulin secretion, and oxygen consumption. We conclude that hydroxyethyl starch does not bring about any further improvement in immediate postischemic organ quality assessed in an in vitro reperfusion system.

The effect of different solutions for organ preservation on immediate postischemic pancreatic function in vitro

The present study compares the effect of organ preservation with Euro-Collins solution, cardioplegic histidine-tryptophan-ketoglutarate solution, and University of Wisconsin solution on immediate pancreatic function after cold storage at 4 degrees C for 24 hr. Postischemic organ quality of a porcine pancreas preparation was tested by quantification of physiological and biomedical parameters in a one-line reperfusion system. During reperfusion with a constant arterial pressure the arteriovenous flow rate was significantly higher for HTK (5.7 +/- 0.91 ml/min, n = 8; P < 0.05 vs. EC) and UW (7.4 +/- 0.81 ml/min, n = 8; P < 0.05 vs. EC) than for EC (3.0 +/- 0.26 ml/min, n = 6). The lowest lactate content in the reperfusate was found after HTK protection (HTK, 64.0 +/- 7.2 mumol/50 ml, n = 8; versus EC, 114.2 +/- 1.7 mumol/50 ml, n = 6, P < 0.001; versus UW, 148.0 +/- 28.6 mumol/50 ml, n = 8, P < 0.05). Amylase in the venous effluent was significantly lower (P < 0.05) for HTK or UW protection than for EC (HTK, 189 +/- 72.6 U/ml; UW, 188 +/- 39.4 U/ml; EC, 416 +/- 71.7 U/ml). Oxygen consumption during reperfusion was significantly higher for HTK (2.15 +/- 0.22 microliters/g/min, P < 0.001) and UW (1.80 +/- 0.52 microliters/g/min, P < 0.05) than for EC (0.47 +/- 0.13 microliters/g/min). We conclude that immediate postischemic organ quality and pancreatic function after protection with HTK is not inferior to preservation with UW.

Effect of total extrinsic denervation and atropine on HCl-stimulated pancreatic exocrine secretion and CCK release in conscious dogs

In 10 dogs with pancreatic fistulas, we studied the effect of extrinsic pancreatic innervation and atropine on protein and bicarbonate secretion and cholecystokinin (CCK) release after intraduodenal perfusion with HCl. Before and after extrinsic denervation of the pancreas, the dogs were given 0.05 M HCl in increasing doses (1.5-48 mmol/h). Tests were repeated with atropine. Increasing doses of HCl resulted in a dose-dependent release of protein and bicarbonate output in both the intact and the denervated pancreas. However, pancreatic denervation significantly decreased pancreatic secretion in response to low loads but not to high loads of HCl. HCl-stimulated CCK release was not altered by pancreatic denervation. In the intact pancreas, atropine significantly reduced bicarbonate and protein response to low loads but not to high doses of HCl. In the denervated gland, atropine had no further inhibitory effect on exocrine pancreatic secretion. Furthermore, atropine showed no influence on HCl-stimulated CCK release under either condition.

[Effect of pancreatic innervation on exocrine secretory performance of the pancreas]

In the present study we examined the influence of extrinsic pancreatic innervation on exocrine pancreatic response to secretin, caerulein, tryptophan and fat, and furthermore the amino acid- and fat-stimulated release of neurotensin and CCK in dogs. Denervation of the pancreas did not alter secretory response to secretin and caerulein, whereas transsection of the extrinsic nerves significantly diminished the protein response to tryptophan and fat. Release of CCK was not altered by pancreatic denervation. However, fat-evoked neurotensin plasma levels were significantly increased after denervation of the pancreas.

Endocrine response to intragastric and intravenous glucose challenge in the denervated dog pancreas

The functional connection between the gut and the islet cells comprises nerves and gastrointestinal hormones. In this study, we quantified the incretin effect and the glucose tolerance (KG value) before and after denervation of the pancreas in dogs in order to find out whether the incretin effect is mediated by nerves. The participation of nerves was estimated by comparing metabolic tests before and after total extrinsic pancreatic denervation in 10 dogs. Fifty-nine percent of the insulin response after intragastric glucose was calculated preoperatively to be the result of incretin factors, a value similar to the 62% found in the postoperative series (with denervated pancreas). The response of GIP to intragastric glucose was not significantly different between pre- and postoperative tests. The KG values pre- and postoperative were in the same range. From our data, we conclude that extrinsic nerves of the pancreas do not seem to play an important role in mediating glucose homeostasis in dogs.

[Endoscopic hernia repair]

A laparoscopic procedure for surgical hernia repair is reported. In comparison to other methods we do not only remove the peritoneal sac, but close although the inguinal canal with a nonresorbable marlex mesh. Up to now we practiced this technique in 35 patients. First post-operative results are encouraging but nothing can be said about longterm results, especially the recurrence rate.

[Influence of extrinsic denervation of the pancreas on food-stimulated pancreas secretion and cholecystokinin and neurotensin release in the dog]

In the present study we examined the effect of extrinsic pancreatic denervation on meal-stimulated pancreatic exocrine secretion and the release of neurotensin and CCK in dogs. Denervation of the pancreas significantly decreased protein output from preoperatively 16,661 +/- 1824 mg x 150 min to 2033 +/- 316 mg x 150 min postoperatively (p less than 0.001), and bicarbonate secretion from 297.5 +/- 36 mmol x 150 min to 104.85 +/- 16 mmol x 150 min (p less than 0.01). Release of neurotensin and CCK was not altered by interruption of the extrinsic pancreatic nerves. Our findings are consistent with the hypothesis that pancreatic secretory response to a meal is predominantly mediated by neutral extrinsic reflexes.

Total denervation of the pancreas does not alter the pancreatic polypeptide-induced inhibition of pancreatic exocrine secretion in dogs

Pancreatic polypeptide (PP) is a potent inhibitor of pancreatic exocrine secretion in vivo. The mechanism of pancreatic inhibition by PP is unknown, but the absence of PP receptors on pancreatic exocrine cells makes a direct effect of this hormone on the gland unlikely. In this study, we investigated the hypothesis that PP exerts its inhibitory effect via extrinsic neural pathways. Ten dogs with gastric and pancreatic fistulas were given an intravenous infusion of 250 ng/kg-1 h-1 secretin and 50 ng/kg-1 h-1 caerulein over 3 h. One hour after starting the infusion, 400 pmol kg-1 h-1 porcine PP were administered over 1 h. Pancreatic bicarbonate and protein secretions were measured. Later, the pancreas was extrinsically denervated. PP infusion decreased bicarbonate secretion in the intact gland by 47% and in the denervated pancreas by 57%. Protein secretion was diminished by exogenous PP by 31% in the intact and by 44% in the denervated pancreas. Despite pancreatic denervation, PP still exerted a significant inhibitory effect. Atropine infusion completely blocked the inhibitory effect of PP on caerulein-stimulated pancreatic protein secretion both in the intact and denervated pancreas and of secretion-evoked bicarbonate output in the denervated gland. We conclude that the inhibitory action of the hormone is not mediated via extrinsic neural pathways of the pancreas, but PP may exert its effect via intrinsic atropine-sensitive mechanisms.

Pediatric falls from heights

Injuries resulting from falls from heights still constitute a significant portion of urban trauma. At this pediatric trauma center, 70 children were admitted from 1985 to 1988 after sustaining a fall of 10 feet or greater or at least one story. The mean patient age was 5 years and 68% of the patients were boys. Seventy-eight percent of falls occurred from 2 stories or less and usually took place at or near the home. Most patients sustained a single major injury and all survived. The majority of injuries involved the head or skeleton and residual functional deficits were uncommon. The incidence of falls from heights has remained high in urban areas despite public education and building codes that require window guards and safety rails.

Preservation of the porcine pancreas with HTK and Euro-Collins solution: studies in a reperfusion system

The present study compares the preservation of the porcine pancreas by the standard Euro-Collins solution or the cardioplegic histidine-tryptophan-ketoglutarate solution (HTK). The explanted pancreas was stored at 4 degrees C for 6 and 24 h respectively, following which organ quality was assessed in a reperfusion chamber measuring physiological and biomedical parameters. After 6 h ischaemia, the amount of lactate was significantly lower when HTK was used for protection. Other parameters like insulin release, amylase release, vascular resistance and oxygen consumption of the pancreas did not indicate a significant difference. Protection with HTK significantly improved pancreas preservation after 24 h ischaemia: lactate content in the reperfusate was lower (HTK: 64.0 +/- 7.2 mumol 50 ml-1 n = 8, v. EC: 114.2 +/- 1.7 mumol 50 ml-1, n = 6), the arteriovenous flow rate was higher (HTK: 5.7 +/- 0.91 ml min-1 v. EC: 3.0 +/- 0.26 ml min-1), and the pancreatic oxygen consumption was increased (HTK: 2.15 +/- 0.22 microliter O2 min-1 g-1 v. 0.47 +/- 0.08 microliter O2 min-1 g-1). We conclude that pancreas preservation can be improved in vitro by protection with HTK solution.

The perfused porcine pancreas as a model for testing organ protective solutions

The present study was designed to establish an in vitro perfused porcine pancreas preparation as a model for testing the effect of organ protective solutions on stimulated pancreatic endocrine and exocrine secretion. The pancreas was prepared and perfused for 10 min with Euro Collins solution, thereafter it was stored in the cold (4 degrees C) for various times. After 3-h and 6-h ischemia pancreatic insulin release in response to glucose was not significantly affected. After 12-h ischemia reduced pancreatic insulin secretin, increased perfusion pressure, and increased amylase and lipase release indicated pancreatic damage. Complete pancreatic dysfunction was seen after 24-h and 48-h ischemia with massive increase in perfusion pressure and low insulin secretion which did not follow a glucose-dependent release pattern, while amylase and lipase concentrations in the perfusion medium increased. Stimulated exocrine pancreatic secretion was significantly decreased already after 3-h ischemia and completely lost after 12 h.

Exocrine pancreatic function in dogs with denervated pancreas

There is strong evidence that the vagus nerve plays an important role in exocrine pancreatic secretion. In the present study we examined the effect of total extrinsic denervation of the pancreas on exocrine pancreatic secretion to different stimuli in dogs. In the experiments we used the model of the orthotopic autotransplanted dog pancreas as described by Debas et al. Denervation of the gland did not significantly alter water and bicarbonate response to secretin. The dose-response curve of caerulein showed the denervated pancreas as sensitive as the intact gland. However, autotransplantation of the pancreas caused a significant decrease (p less than 0.05) in protein secretion during intraintestinal L-tryptophan in increasing doses. Furthermore, bicarbonate and protein secretion after food intake was significantly decreased in the denervated pancreas (protein: peak levels 380 mg/15 min and 135 mg/15 min; bicarbonate: 3.2 mEq/15 min and 1.4 mEq/15 min) (p less than 0.02). From our data we conclude that the denervated pancreas is as sensitive as the intact pancreas to stimulation by exogenous secretin and caerulein, whereas denervation of the pancreas causes an important influence in the intestinal phase of pancreatic secretion.

[Comparison between the radioimmunologic measurement of plasma E2 and estrogen determination in urine using a hemagglutination inhibition test]

To prove the diagnostic value of a new haemagglutination inhibition test (HI-Estrotec), urinary and plasma oestrogens were simultaneously measured in 42 stimulated cycles of 40 women of the Erlangen IVF programme. Comparing the results of all paired samples, there was a correlation coefficient r = 0.6968. Correlating the total oestrogens in the early morning urine with the plasma-E2, the coefficient was r = 0.641. In 26 cases of the 42 stimulated cycles egg retrieval could be performed. Averaging the daily values of these women the graphs of E2 and urinary oestrogens show nearly parallel curves with maximal values on the same day, i.e. the first day after HCG application. Comparing the two curves of the individual patient, in 14 of 26 cases there are differences of more than 24 hours between the maximal values of urinary and plasma oestrogens. The advantages of the HI-Estrotec-Assay are: Simple handling without special demands on the laboratory equipment. The results can be obtained after two hours already. The possibility to measure several times a day without great effort. The disadvantage is: The delayed appearance of the hormones in the urine. To induce ovulation with HCG, however, actual parameters are indispensable. If the ovulation is triggered by the endogenous LH surge the diagnostic value of the new assay is sufficient when it is combined with an LH monitoring.

[Cryoconservation of 8-celled stage rabbit embryos in an automated "open system"]

Rabbit embryos were successfully frozen at the 8-cell stage, employing a rapid and a slow freezing-thawing program. They were then stored at -196 degrees C (liquid nitrogen) for 10 to 60 days. After thawing the embryos were examined for viability in vitro and in vivo. Using the slow program B 82.5% were morphologically intact, compared to only 69.3% after the rapid procedure (program A). 88.8% of the group first mentioned above, and 56.8% of the latter developed to the blastocyst stage after 4 to 5 days in culture. The implantation rate was 18.1%, when embryos were transferred to minus 18 hours asynchronous recipients, after thawing. With 40%, a significantly higher implantation rate could be achieved, when the embryos were transferred to minus 24 hours asynchronous foster mothers. 18 viable young were born 30 to 32 days after transfer.