NASA GEOS Composition Forecast Modeling System GEOS-CF v1.0: Stratospheric Composition.

The NASA Goddard Earth Observing System (GEOS) Composition Forecast (GEOS-CF) provides recent estimates and 5-day forecasts of atmospheric composition to the public in near-real time. To do this, the GEOS Earth system model is coupled with the GEOS-Chem tropospheric-stratospheric unified chemistry extension (UCX) to represent composition from the surface to the top of the GEOS atmosphere (0.01 hPa). The GEOS-CF system is described, including updates made to the GEOS-Chem UCX mechanism within GEOS-CF for improved representation of stratospheric chemistry. Comparisons are made against balloon, lidar, and satellite observations for stratospheric composition, including measurements of ozone (O3) and important nitrogen and chlorine species related to stratospheric O3 recovery. The GEOS-CF nudges the stratospheric O3 toward the GEOS Forward Processing (GEOS FP) assimilated O3 product; as a result the stratospheric O3 in the GEOS-CF historical estimate agrees well with observations. During abnormal dynamical and chemical environments such as the 2020 polar vortexes, the GEOS-CF O3 forecasts are more realistic than GEOS FP O3 forecasts because of the inclusion of the complex GEOS-Chem UCX stratospheric chemistry. Overall, the spatial patterns of the GEOS-CF simulated concentrations of stratospheric composition agree well with satellite observations. However, there are notable biases-such as low NO x and HNO3 in the polar regions and generally low HCl throughout the stratosphere-and future improvements to the chemistry mechanism and emissions are discussed. GEOS-CF is a new tool for the research community and instrument teams observing trace gases in the stratosphere and troposphere, providing near-real-time three-dimensional gridded information on atmospheric composition.

Hepatic steatosis is highly prevalent across the paediatric age spectrum, including in pre-school age children.

BACKGROUND: The prevalence of non-alcoholic fatty liver disease (NAFLD) in children is 8% in the general population, and 34% in the context of obesity. There is a paucity of data on the prevalence of hepatic steatosis in healthy children in Ontario. AIMS: To determine the prevalence of hepatic steatosis using abdominal computed tomography (CT) scans in a cohort of previously healthy children across the paediatric age spectrum in Ontario, Canada, and to determine any association between measures of abdominal adiposity and hepatic steatosis. METHODS: Retrospective review of the SickKids Trauma Database from 2004-2015. Previously healthy children ages 1-17 years having undergone an abdominal CT scan as a part of routine trauma assessment were included, and those with an intra-abdominal injury excluded. Steatosis was defined as a difference between liver and spleen attenuation ≤-25HU. The percentage of the total area occupied by abdominal subcutaneous adipose and visceral adipose tissue was measured. Anthropometrics and baseline demographics were collected. RESULTS: A total of 503 (51% male) children with mean (±SD) age 9.5 ± 4.5 years and weight z-score of 0.37 ± 1.05 were studied. Seventy-seven (15%, 95% CI [12%-18%]) had hepatic steatosis; no differences found between sexes or across age quartiles. The abdominal subcutaneous adipose tissue area was greater in those with hepatic steatosis compared to those without (32% [22-42] vs 24% [17-36], P = 0.003). The visceral adipose tissue area was significantly greater in older children ≥9.8 years with hepatic steatosis (7.7% [5.1-10] vs 6.6% (4.9-8.5), P = 0.04). CONCLUSION: Hepatic steatosis was highly prevalent in previously healthy children in Ontario, including children of pre-school age. We found an association between hepatic steatosis and abdominal subcutaneous adipose tissue, and in older children with visceral adipose tissue.

Elevated α-synuclein caused by SNCA gene triplication impairs neuronal differentiation and maturation in Parkinson's patient-derived induced pluripotent stem cells.

We have assessed the impact of α-synuclein overexpression on the differentiation potential and phenotypic signatures of two neural-committed induced pluripotent stem cell lines derived from a Parkinson's disease patient with a triplication of the human SNCA genomic locus. In parallel, comparative studies were performed on two control lines derived from healthy individuals and lines generated from the patient iPS-derived neuroprogenitor lines infected with a lentivirus incorporating a small hairpin RNA to knock down the SNCA mRNA. The SNCA triplication lines exhibited a reduced capacity to differentiate into dopaminergic or GABAergic neurons and decreased neurite outgrowth and lower neuronal activity compared with control cultures. This delayed maturation phenotype was confirmed by gene expression profiling, which revealed a significant reduction in mRNA for genes implicated in neuronal differentiation such as delta-like homolog 1 (DLK1), gamma-aminobutyric acid type B receptor subunit 2 (GABABR2), nuclear receptor related 1 protein (NURR1), G-protein-regulated inward-rectifier potassium channel 2 (GIRK-2) and tyrosine hydroxylase (TH). The differentiated patient cells also demonstrated increased autophagic flux when stressed with chloroquine. We conclude that a two-fold overexpression of α-synuclein caused by a triplication of the SNCA gene is sufficient to impair the differentiation of neuronal progenitor cells, a finding with implications for adult neurogenesis and Parkinson's disease progression, particularly in the context of bioenergetic dysfunction.

Pediatric intestinal transplant listing criteria - a call for a change in the new era of intestinal failure outcomes.

Current listing indications used for intestinal transplantation (IT) were proposed in 2001. We undertook the present single center study to see if these criteria are still valid. The 2001 criteria (advanced cholestasis, loss of >50% central venous catheter (CVC) sites, ≥2 sepsis/year, ultrashort bowel) were compared in children with intestinal failure in old era-1998-2005 (N = 99) to current era-2006-2012 (N = 91) to predict the need for IT using sensitivity, specificity, NPV and PPV. Two 2001 criteria had poorer predictive value in the current era: Advanced cholestasis (PPV 64% old vs. 40% current era; sensitivity 84% vs. 65%, respectively) and ultrashort bowel (PPV 100% old vs. 9% current era; sensitivity 10% vs. 4%, respectively). Three newly proposed criteria had high predictive value: ≥2 ICU admissions (p = 0.0001, OR 23.6, 95% CI 2.7-209.8), persistent bilirubin >75 mmol/L despite lipid strategies (p = 0.0005, OR 24.0, 95% CI 3.2-177.4), and loss of ≥3 CVC sites (p = 0.0003, OR 33.3, 95% CI 18.8-54.0). There was 98% probability of needing IT when two of these new criteria were present. The 2001 IT criteria have limited predictive ability in the current era and should be revised. A multicenter study is required to validate the findings of this single center experience.

What is the current role for parenteral lipid emulsions containing omega-3 fatty acids in infants with short bowel syndrome?

Parenteral nutrition associated liver disease is the most common complication of pediatric short bowel syndrome (SBS). There is emerging evidence that the disease may be reversed with the use of parenteral lipid emulsions derived from fish-oils, which contain significant concentrations of omega-3 fatty acids (w3FA). This paper will review the rationale for the use of parenteral lipid emulsions containing w3FA in SBS and the evidence for their efficacy. Given the promising results and apparent safety of these emulsions, we shall also consider what the current role for PN lipid emulsions containing w3FA in children with SBS should be.

The two-week pediatric surgery rotation: is it time wasted?

BACKGROUND: With increasing medical school emphasis on generalist training and decreasing enrollment in surgical residency, the authors assessed the adequacy of a 2-week pediatric surgery rotation on meeting the learning and competency objectives outlined in The Canadian Association of Pediatric Surgeons' Self-Directed Evaluation Tool. METHODS: A prospective survey was conducted of 39 clinical clerks. An anonymous self-assessment scale measuring competency objectives (medical and psychosocial) was administered pre-and postrotation. Also, exposure to pediatric surgical conditions from a list of "essential" and "nonessential" learning objectives was measured. Statistical analysis was performed using paired t test with significance at.05 level. RESULTS: Response rate was 77% and 54% for the competency and learning objectives, respectively. Students reported improvement in medical (P <.00001; 95% CI, 1.30, 1.90) and psychosocial (P =.00036; 95% CI 0.64, 1.28) competency objectives after the rotation. Almost all "essential" learning objectives were met. Overall, students reported an increased awareness of the breadth of pediatric surgical practice (P <.0001; 95% CI 2.06, 3.18). CONCLUSIONS: A 2-week rotation in pediatric surgery appears adequate in fulfilling most competency and learning objectives, but discussion is needed about how to best assess student competency, which topics are considered essential, and the long-term effect on recruitment to the profession.

Acute chest syndrome after abdominal surgery in children with sickle cell disease: Is a laparoscopic approach better?

BACKGROUND/PURPOSE: Acute chest syndrome (ACS) is the leading cause of hospitalization and death among patients with sickle cell disease (SCD). Surgery is a risk factor for the development of ACS. It has been suggested that laparoscopic surgery could diminish the risk of sickle-related complications; therefore, more procedures may be encouraged in asymptomatic patients. The goal of the authors was to determine the incidence of postoperative ACS and assess for predisposing factors in all sickle cell patients undergoing abdominal surgery. METHODS: A retrospective analysis of all sickle cell patients receiving abdominal surgery (open and laparoscopic) between 1994 and 1998 was conducted. Data pertaining to demographics, perioperative clinical status, postoperative care, and outcome were collected and analyzed using Student's t test or chi(2) where appropriate. RESULTS: Fifty-four children underwent 62 procedures (35 abdominal and 27 extracavitary). All abdominal cases were either cholecystectomy or splenectomy (22 laparoscopic and 13 open). ACS occurred in 7 of 62 (11.3%) overall, and all were in abdominal cases 7 of 35 (20%). ACS occurred in 5 of 22 (22.7%) laparoscopic cases and 2 of 13 (15.4%) open cases. Operating time was significantly longer in the laparoscopic group compared with open cases (P <.05). A higher percentage of patients who had ACS had at least 1 previous episode (71.4% v 39.3%; P value not significant) and a smaller percentage of ACS patients received a preoperative blood transfusion (14.3% v 32.1%; P value not significant). Postoperative hospitalization was prolonged if ACS occurred (9 +/- 2 v 3 +/- 2 days; P <.05). CONCLUSIONS: Abdominal surgery carries a significantly high risk (20%) of ACS. Laparoscopy does not decrease the incidence of ACS compared with open approach. Predisposing factors were not significant in predicting postoperative ACS. There is considerable morbidity and potential cost implications in patients with ACS.

Directed blood donation in pediatric general surgery: Is it worth it?

PURPOSE: To date, there are no data to support the safety, efficacy, and cost-benefit ratio of donor-directed blood donation (DD). The objectives were to determine whether a DD program in pediatric general surgery practice is justified. METHODS: A retrospective analysis was conducted of the transfusion practice and all DD requests received by transfusion services in a full calendar year (1997) at a tertiary care pediatric hospital. The authors examined the donations, utilization, and possible benefits for the recipients. RESULTS: A total of 22,527 units of blood were transfused in 1997. General surgery used 471 (2%) of the total and 471 of 4,825 (10%) of all surgical transfusions. Total DD requests were 219 with only 11 of 219 (5%) originating from the general surgery department. After all the exclusions, 133 of 219 (61%) requests had DD blood available. DD blood had a higher true-positive rate for transmissible disease (1.1% v 0.10%), high-risk activity (2.5% v 1.2%), and malaria risk (3.1% v 0.31%). Total utilization of DD blood was 132 of 236 units (55.9%) and general surgery utilized 4 of 11 (36.4%) of their directed donations. Thirty-seven patients (27.8%) benefited from decreased donor exposure. No general surgery patient received more than 1 blood component to benefit from decreased donor exposure. CONCLUSIONS: DD deferral rates are higher than for volunteer donors for infectious disease markers, malaria, and high-risk activities. There is no evidence that DD is safer than volunteer donation. DD blood wastage of 63.6% is much higher than in volunteer donation (7%). Thirty-seven patients (28%) received multiple units from one donor suggesting a benefit from decreased donor exposure. Given the low frequency of transfusion and the poor utilization of DD in general surgical practice, a DD program is not justified.

Long-term outcome after nonoperative management of complete traumatic pancreatic transection in children.

PURPOSE: The treatment of complete pancreatic transection (CPT) from blunt trauma remains controversial. To determine the natural history and long-term outcome of nonoperative management of CPT, we analyzed all such patients over the last 10 years at a level I trauma center. METHODS: Retrospective analysis between 1990 and 1999 was performed on 10 consecutive patients. Complete records were available for 9 patients. Data pertaining to their trauma admission, plus long-term radiologic and clinical outcome were analyzed. RESULTS: There were 6 boys and 3 girls with a median age of 8 years (range, 4 to 16 years) and a median injury severity score (ISS) of 25. All patients displayed CPT on admission computed tomography (CT) scan. Four patients (44%) had associated intraabdominal injuries, but only 2 were significant. All patients were treated nonoperatively. Four patients (44%) had pseudocysts, and 3 required percutaneous drainage. Other complications included a single drainage of subphrenic collection, 1 inadvertent removal of drainage catheter, and 2 cases of line sepsis. The duration of percutaneous drainage was 14 to 60 days. The median length of hospitalization was 24 days (range, 6 to 52 days). After median follow up of 47 months, no patients showed exocrine or endocrine insufficiency. One patient had abdominal pain not related to the pancreatic injury. Follow-up abdominal CT scans in 8 of 9 patients showed complete atrophy of the body and tail in 6 patients and 2 completely normal glands. CONCLUSIONS: Pancreatic transection is rare and commonly is found in isolation of other major abdominal injuries. No patients required surgery for their pancreatic transection. Pseudocysts can be managed effectively with percutaneous drainage. After a median follow-up of 47 months, no patients had endocrine or exocrine dysfunction. Anatomically, the distal body and tail usually atrophies; however, occasionally, the gland can heal and appear to recanalize. To the authors' knowledge, this is the first report to show the effectiveness of nonoperative management after complete pancreatic transection.

Six-month follow-up of children with obstructive sleep apnoea.

OBJECTIVES: This study examined prospectively changes in development, temperament and sleep related behaviour in children referred for obstructive sleep apnoea (OSA) and polysomnographic sleep study, some of whom had surgical intervention. METHODOLOGY: Using a prospective cohort study design, parents of 56 children referred for OSA completed sleep and temperament questionnaires and their child was assessed developmentally at the time of the polysomnographic sleep study. Forty (72%) of the children were neurologically normal. At 6 months, 42 children were reassessed using sleep and temperament questionnaires and a developmental assessment. After excluding the primary snorers, subjects were categorised as having had intervention (n = 24) or not (n = 15), and differences over the 6-month period in Griffiths scores, temperament and sleep related behaviour were examined. RESULTS: Regardless of intervention status, there was an improvement in night-time and day-time sleep behaviour for the total group, though the extent of improvement was more marked in the intervention group. For the neurologically normal children, improvement in the sleep behaviour was only significant for the intervention group (P < 0.05). Intervention did not result in any significant changes in Griffiths developmental score or temperament. CONCLUSION: Surgical intervention improves sleep behaviour in children though not temperament or development.

Aetiological factors and development in subjects with obstructive sleep apnoea.

OBJECTIVE: To examine whether maternal pregnancy complications, adverse birth events, respiratory illnesses, or developmental difficulty were increased in neurologically normal children with obstructive sleep apnoea (OSA) and whether severity of OSA adversely affects the child's development and temperament. METHODOLOGY: Maternal report of perinatal events, respiratory illness and developmental difficulty in 37 children with OSA was contrasted with a comparison group (n = 67). Children with OSA were assessed developmentally (Griffiths Scales), had a parental rating of temperament (Australian Temperament Scale) and attended an overnight polysomnographic sleep study. RESULTS: Children with OSA had an increased prevalence of adverse maternal pregnancy and perinatal events, respiratory disease and developmental concerns. Limited associations were found between the severity of OSA and development or temperament difficulty. CONCLUSIONS: This study suggests a relationship between OSA, though not its severity, and pre/perinatal adversity and child development. Polysomnographic and detailed developmental assessment of community-based samples of children with OSA and control children are necessary to confirm these findings.

Clinical versus polysomnographic profiles in children with obstructive sleep apnoea.

OBJECTIVE: To examine the clinical and polysomnographic (PSG) profiles of neurologically normal and abnormal children with obstructive sleep apnoea (OSA) and explore the relationship between these profiles. METHODOLOGY: We enrolled 56 children with persistent snoring and OSA for the study, 16 of whom were neurologically abnormal. All children were examined clinically and attended an overnight PSG study. Total clinical scores, PSG scores, and mild/moderate or severe ratings were derived for each child. RESULTS: Comparison of individual PSG parameters with neurological status demonstrated that the abnormal children had significantly increased obstructive apnoea indices, increased desaturation events and lower mean arousal indices compared to their neurologically normal OSA peers. For the neurologically abnormal children, there was a significant correlation between severity ratings of disease according to clinical and PSG profiles (r = 0.56, P = 0.03, sensitivity 82%) using the clinical summary as the gold standard, although the association was less marked in the neurologically normal children (r = -0.08, P = NS, sensitivity 69%). CONCLUSION: Neurologically abnormal children are likely to have more severe abnormalities in selected polysomnographic indices and overall scores. However, the clinical assessment is only likely to reflect this at the severe end of the spectrum. These relationships are not seen in the neurologically normal child, where little or no reliance can be placed upon predicting the severity of the polysomnographic findings from the clinical data. Decisions regarding the severity of disease and treatment should be based on the combined findings of the clinical and PSG data rather than overall clinical and polysomnographic scores or selected clinical and polysomnographic parameters.

Solution-focused brief therapy in primary care.

Solution-focused brief therapy (SFBT) offers mental health nurses a robust framework on which to build appropriate and effective nursing care. This article describes efforts to apply ideas derived from this type of therapy in a new nurse practitioner post offering a mental health service to patients based in GP practices. The approach described develops Brimblecombe's (1995) idea of combining a brief therapy approach with nursing care plans in a way ideally suited to time-limited mental health nursing in primary care.

Perception of body image in children with burns, five years after burn injury.

Burn injuries and subsequent disfigurement may place children at high risk for psychologic dysfunction. If medical professionals are to aid the child in achieving psychologic resolution and acceptance of the injury, they must be aware of the stage of body-image perception that the child is experiencing. This study was designed to determine differences in body image between children with burns and children without burns through the use of human figure drawings. The experimental group consisted of 32 children with burns, aged 5 to 15 years, studied at approximately 5 years after burn injury. The control group consisted of 32 children without burns, aged 6 to 15 years. Subjects in the burn group were matched to control subjects by age and sex. There were no significant differences in body image in relation to any of the demographic measures except age. Age was inversely related to body image both in patients with burns and in control subjects.